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Before modern indexed shifting became standard, some bicycles used fully mechanical automatic derailleur systems that changed gears without any rider input. Designs like the Suntour Auto Shift relied on centrifugal force generated by rear wheel rotation to control when and how the drivetrain shifted. As speed increased, internal rotating... weights inside the mechanism moved outward, activating linkages that adjusted cable tension. This movement guided the derailleur across the cassette, allowing the bike to shift into higher gears automatically, then return to lower gears as speed dropped. Although innovative, these systems were sensitive to setup and riding conditions, which limited their long term adoption. Advances in indexed shifters and rider demand for precise manual control eventually replaced automatic mechanical solutions, turning designs like this into a rare but fascinating chapter in cycling engineering history. Video Credit: rbcbikesshow more

Mechanical Knowledge

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533,526 次观看 • 4 个月前 •via X (Twitter)

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🗣️ "We simply will not tolerate people risking the safety of others and themselves by riding electric bikes at speed on our roads and pavements" Yesterday, proactive Roads Policing patrols on Stonebridge Lane saw a vehicle appearing to be exceeding 40mph at about 5pm, but when officers engaged with the rider he rode away. The suspect narrowly missed a pedestrian and was pursued around a nearby housing estate. He rode on pavements and pulled into the path of a car that had to brake suddenly before losing control of the bike and falling off. As the suspect tried to get back on the bike, the officers carefully drove their vehicle onto the bike’s back wheel and detained the rider. A 19-year-old man from Old Swan was arrested on suspicion of dangerous driving, drug driving, failing to stop, driving a motor vehicle otherwise than in accordance with a licence and using a motor vehicle without third party insurance. He has been released under investigation. The bike was found to be capable of top speeds of more than 50mph as well as having worn tyres, no brakes on the rear wheel and pedals that did not function❌ 🚳 Through Operation Gears, we are taking proactive action by seizing illegal bikes, arresting offenders, and increasing high-visibility patrols where the public and our own patrols identify issues. ➡️ Our activity is aimed at disrupting criminality and ultimately protecting our communities. #OpGears #SaferStreets #Arrest

🗣️ "We simply will not tolerate people risking the safety of others and themselves by riding electric bikes at speed on our roads and pavements" Yesterday, proactive Roads Policing patrols on Stonebridge Lane saw a vehicle appearing to be exceeding 40mph at about 5pm, but when officers engaged with the rider he rode away. The suspect narrowly missed a pedestrian and was pursued around a nearby housing estate. He rode on pavements and pulled into the path of a car that had to brake suddenly before losing control of the bike and falling off. As the suspect tried to get back on the bike, the officers carefully drove their vehicle onto the bike’s back wheel and detained the rider. A 19-year-old man from Old Swan was arrested on suspicion of dangerous driving, drug driving, failing to stop, driving a motor vehicle otherwise than in accordance with a licence and using a motor vehicle without third party insurance. He has been released under investigation. The bike was found to be capable of top speeds of more than 50mph as well as having worn tyres, no brakes on the rear wheel and pedals that did not function❌ 🚳 Through Operation Gears, we are taking proactive action by seizing illegal bikes, arresting offenders, and increasing high-visibility patrols where the public and our own patrols identify issues. ➡️ Our activity is aimed at disrupting criminality and ultimately protecting our communities. #OpGears #SaferStreets #Arrest

Merseyside Police

16,462 次观看 • 1 年前

Robots that act like slime! 🫟 Cornell University engineers developed a robotic collective that behaves less like a machine and more like a material that flows, reshapes, and adapts without centralized control. It consists of dozens of small robots with limited individual mobility that exhibit coordinated motion when entangled. The system resembles soft matter, continuously deforming and reorganizing as it moves, driven by mechanical intelligence. Each robotic module measures 200mm long and 20mm wide, containing a small motor that oscillates between "I" and "U" shapes. These oscillations generate forces against the ground, allowing modules to inch forward and jostle together. On their own, modules move slowly and inefficiently. When they entangle into chains, they self-organize into shifting configurations that prove resilient in challenging environments. On incline surfaces, chains moved more reliably than individuals. In obstacle fields, the collective behaved like a flowing material, connections formed to maintain cohesion, then broke apart to prevent jamming. The system stays functional even when modules fail. Isolated modules emit an audible distress signal, prompting nearby modules to slow down so the straggler can reconnect. No centralized sensing or control, each module infers when it has lost contact by how much it's being jostled. Read more here: ~~ ♻️ Join the weekly robotics newsletter, and never miss any news →

Robots that act like slime! 🫟 Cornell University engineers developed a robotic collective that behaves less like a machine and more like a material that flows, reshapes, and adapts without centralized control. It consists of dozens of small robots with limited individual mobility that exhibit coordinated motion when entangled. The system resembles soft matter, continuously deforming and reorganizing as it moves, driven by mechanical intelligence. Each robotic module measures 200mm long and 20mm wide, containing a small motor that oscillates between "I" and "U" shapes. These oscillations generate forces against the ground, allowing modules to inch forward and jostle together. On their own, modules move slowly and inefficiently. When they entangle into chains, they self-organize into shifting configurations that prove resilient in challenging environments. On incline surfaces, chains moved more reliably than individuals. In obstacle fields, the collective behaved like a flowing material, connections formed to maintain cohesion, then broke apart to prevent jamming. The system stays functional even when modules fail. Isolated modules emit an audible distress signal, prompting nearby modules to slow down so the straggler can reconnect. No centralized sensing or control, each module infers when it has lost contact by how much it's being jostled. Read more here: ~~ ♻️ Join the weekly robotics newsletter, and never miss any news →

Lukas Ziegler

13,026 次观看 • 2 个月前

If drivers fail this test in Sweden, they will not get a license. The test is called skid pan training, known as halkbana in Sweden, which is a mandatory slippery-road control exam that drivers must pass to secure a license. During the exam, drivers must navigate specially treated tracks coated in water or oil to simulate real-world conditions like black ice and heavy snow packs. Instructors purposely force the vehicle into sudden spins or slides, requiring the student to successfully steer out of danger and regain complete control of the car. The training also teaches drivers exactly how speed, vehicle weight, and braking distance change when driving on zero-traction surfaces. Scandinavian governments mandate this hands-on test because standard road exams on dry asphalt do not prepare drivers for the severe, unpredictable winters of northern Europe. Failing to demonstrate proper vehicle recovery techniques or showing reckless behavior on the track results in an automatic failure. [🎞️ didyouknow]

If drivers fail this test in Sweden, they will not get a license. The test is called skid pan training, known as halkbana in Sweden, which is a mandatory slippery-road control exam that drivers must pass to secure a license. During the exam, drivers must navigate specially treated tracks coated in water or oil to simulate real-world conditions like black ice and heavy snow packs. Instructors purposely force the vehicle into sudden spins or slides, requiring the student to successfully steer out of danger and regain complete control of the car. The training also teaches drivers exactly how speed, vehicle weight, and braking distance change when driving on zero-traction surfaces. Scandinavian governments mandate this hands-on test because standard road exams on dry asphalt do not prepare drivers for the severe, unpredictable winters of northern Europe. Failing to demonstrate proper vehicle recovery techniques or showing reckless behavior on the track results in an automatic failure. [🎞️ didyouknow]

Massimo

453,263 次观看 • 1 天前

What is the RAT? The RAT is a small wind turbine stowed within the aircraft fuselage and deployed automatically when certain failure conditions are met. Once extended into the airstream, it uses the forward motion of the aircraft to spin and generate power—mechanical, hydraulic, or electrical. Primary Functions of the RAT on the 787-8 1. Hydraulic Backup Power On deployment, the RAT drives a variable displacement inline hydraulic pump. It pressurizes the center hydraulic system, enabling continued operation of critical flight control surfaces such as the ailerons, elevators, and rudder. This is vital in maintaining aircraft controllability if normal hydraulic sources are lost. 2. Supplementary Electrical Power While the RAT is primarily a hydraulic power source on the 787-8, it can also, in some configurations, drive an emergency generator. This generator provides sufficient AC and DC power to support essential avionics, flight displays, and communications systems. Deployment Scenarios: When Does the RAT Automatically Deploy? The RAT on the Boeing 787-8 deploys automatically—without crew input—under the following emergency conditions: 1. Dual Engine Failure If both engines fail, resulting in the loss of engine-driven electrical and hydraulic generation, the RAT deploys to maintain critical flight control power. 2. Complete Electrical Loss to Flight Instruments If there’s a total loss of electrical power to both the captain’s and first officer’s primary flight instruments, the RAT ensures these systems remain powered. 3. Low Pressure in All Three Hydraulic Systems If all three systems—Left, Center, and Right—lose hydraulic pressure, the RAT provides emergency hydraulic power through the center system. 4. EMP Failure + Engine Loss During Takeoff or Landing If all four Electric Motor Pumps (EMPs) fail and an engine fails during takeoff or landing, the RAT deploys to sustain flight control power during these critical phases. Automatic and Autonomous Operation One of the RAT’s key advantages is its fully autonomous activation. Pilots do not need to manually deploy it; the system is designed to react immediately to predefined failure logic, reducing workload and ensuring flight-critical systems remain powered. In Summary The Ram Air Turbine (RAT) on the Boeing 787-8 is not just a backup—it's a lifesaving last resort. It deploys automatically to supply hydraulic and limited electrical power when all other power sources fail. Designed with layered redundancy in mind, it is one of the unsung heroes of modern aircraft systems, ensuring that even in worst-case scenarios, pilots retain control to guide the aircraft—and its passengers—safely to the ground.

What is the RAT? The RAT is a small wind turbine stowed within the aircraft fuselage and deployed automatically when certain failure conditions are met. Once extended into the airstream, it uses the forward motion of the aircraft to spin and generate power—mechanical, hydraulic, or electrical. Primary Functions of the RAT on the 787-8 1. Hydraulic Backup Power On deployment, the RAT drives a variable displacement inline hydraulic pump. It pressurizes the center hydraulic system, enabling continued operation of critical flight control surfaces such as the ailerons, elevators, and rudder. This is vital in maintaining aircraft controllability if normal hydraulic sources are lost. 2. Supplementary Electrical Power While the RAT is primarily a hydraulic power source on the 787-8, it can also, in some configurations, drive an emergency generator. This generator provides sufficient AC and DC power to support essential avionics, flight displays, and communications systems. Deployment Scenarios: When Does the RAT Automatically Deploy? The RAT on the Boeing 787-8 deploys automatically—without crew input—under the following emergency conditions: 1. Dual Engine Failure If both engines fail, resulting in the loss of engine-driven electrical and hydraulic generation, the RAT deploys to maintain critical flight control power. 2. Complete Electrical Loss to Flight Instruments If there’s a total loss of electrical power to both the captain’s and first officer’s primary flight instruments, the RAT ensures these systems remain powered. 3. Low Pressure in All Three Hydraulic Systems If all three systems—Left, Center, and Right—lose hydraulic pressure, the RAT provides emergency hydraulic power through the center system. 4. EMP Failure + Engine Loss During Takeoff or Landing If all four Electric Motor Pumps (EMPs) fail and an engine fails during takeoff or landing, the RAT deploys to sustain flight control power during these critical phases. Automatic and Autonomous Operation One of the RAT’s key advantages is its fully autonomous activation. Pilots do not need to manually deploy it; the system is designed to react immediately to predefined failure logic, reducing workload and ensuring flight-critical systems remain powered. In Summary The Ram Air Turbine (RAT) on the Boeing 787-8 is not just a backup—it's a lifesaving last resort. It deploys automatically to supply hydraulic and limited electrical power when all other power sources fail. Designed with layered redundancy in mind, it is one of the unsung heroes of modern aircraft systems, ensuring that even in worst-case scenarios, pilots retain control to guide the aircraft—and its passengers—safely to the ground.

Turbine Traveller

293,307 次观看 • 1 年前

April 30 • 12:00pm ET Art Blocks + OpenSea “Gift of time” began during my residency in Marfa, Texas, as part of the Art Blocks and OpenSea artist residency program, where a distinct shift in the experience of time became central to the work. In the desert, I felt time move differently. It stretched, slowed, and became something I noticed. After a few days, the rhythm changed. Moments felt longer, attention sharpened, and I became increasingly aware of each moment as it passed. This work comes from that condition. Time is not treated only as a theme, but as a system embedded in the structure of the piece. Different ways of measuring time, such as mechanical cycles, calendars, and lunar phases, are translated into rules that continuously transform the work. The piece does not represent time. It runs on it. Its movement is tied to blockchain time. Even when unseen, it continues to rotate and evolve. When loaded, it synchronizes with the present moment, but it does not begin when it is viewed, and it does not stop when it disappears from the screen. During the residency, I spent hours thinking, sketching, and making connections. Those connections are also visible. Elastic lines, like rubber bands, link elements across the piece, representing how memories connect, how one thought leads to another, and how everything builds over time. These same connections introduce moments where the system attempts to pull itself back, as if trying to regain control. But it never fully resets. It is not a loop. The movement continues, drifting forward, never returning to a fixed state. Visually, the work reveals its own construction. Lines, paths, and rotations expose an internal logic, like looking inside a mechanism. The drawing language recalls diagrams, technical sketches, or the interior of a mechanical watch. It is a system in motion, always active. “Gift of Time” exists because I was given time by Art Blocks, OpenSea, and above all my family. It is my way of saying thank you. It is both a reflection on time and a product of it. April 30 @ 12:00pm ET on Art blocks & OpenSea 1 / 1 / 365 • 0.02 Eth Art Blocks, OpenSea

April 30 • 12:00pm ET Art Blocks + OpenSea “Gift of time” began during my residency in Marfa, Texas, as part of the Art Blocks and OpenSea artist residency program, where a distinct shift in the experience of time became central to the work. In the desert, I felt time move differently. It stretched, slowed, and became something I noticed. After a few days, the rhythm changed. Moments felt longer, attention sharpened, and I became increasingly aware of each moment as it passed. This work comes from that condition. Time is not treated only as a theme, but as a system embedded in the structure of the piece. Different ways of measuring time, such as mechanical cycles, calendars, and lunar phases, are translated into rules that continuously transform the work. The piece does not represent time. It runs on it. Its movement is tied to blockchain time. Even when unseen, it continues to rotate and evolve. When loaded, it synchronizes with the present moment, but it does not begin when it is viewed, and it does not stop when it disappears from the screen. During the residency, I spent hours thinking, sketching, and making connections. Those connections are also visible. Elastic lines, like rubber bands, link elements across the piece, representing how memories connect, how one thought leads to another, and how everything builds over time. These same connections introduce moments where the system attempts to pull itself back, as if trying to regain control. But it never fully resets. It is not a loop. The movement continues, drifting forward, never returning to a fixed state. Visually, the work reveals its own construction. Lines, paths, and rotations expose an internal logic, like looking inside a mechanism. The drawing language recalls diagrams, technical sketches, or the interior of a mechanical watch. It is a system in motion, always active. “Gift of Time” exists because I was given time by Art Blocks, OpenSea, and above all my family. It is my way of saying thank you. It is both a reflection on time and a product of it. April 30 @ 12:00pm ET on Art blocks & OpenSea 1 / 1 / 365 • 0.02 Eth Art Blocks, OpenSea

Manuel Lariño ☔️

21,901 次观看 • 3 个月前

Seedance 2.0 on Nsketch AI Prompt: Speeder chase across a cliff city (single continuous shot) From a monumental cliffside city carved into stone, the camera dives toward a tiny streak of light ripping along a narrow ledge-road. Lock-on: a speeder hugging the wall at insane speed. The camera slingshots ahead, whips back, then drops tight to the rear thrusters: heat haze, grit snapping off the ledge, warning lights flashing. A collapsing balcony rains debris; the rider snaps a last-inch swerve under a falling arch, then threads through hanging laundry lines and open windows in one fluid line. The camera darts through the same openings, staying glued to the motion. One final bend and sudden calm: the camera blasts outward into a reveal of the city opening onto a boundless waterfall-fed valley, mist turning into rainbow.The rainbow mist lingers for half a second — serenity — then a SHADOW slices across it. From above, two black pursuit speeders dive through the mist, engines screaming. The camera tilts up just as the lead speeder banks hard off the cliff edge, skimming inches above the waterfall’s roaring drop. Spray explodes across the lens but never cuts. The camera rolls with the rider as they plunge straight down the waterfall face — not falling, but riding the vertical air current. Thrusters flare blue-white, stabilizers flickering. Pursuit crafts follow, firing pulse shots that streak through the mist like comets. The rider kicks sideways into a cavern hidden behind the waterfall curtain. The camera punches through liquid light into darkness — bioluminescent moss ignites along the cave walls, revealing an ancient tunnel carved by forgotten hands. Water drips in slow motion as the speed never drops. The camera swings low beneath the speeder, hugging the water-slick stone. Sparks burst as the underside grazes rock. Ahead: a broken bridge spanning a massive underground chasm. No slowdown. The rider guns it. The camera races ahead, flips 180° mid-air as the speeder launches the gap. For a breathless second, only void below — a bottomless abyss glowing faintly with magma veins. Mid-jump, one pursuer clips the edge and spirals down, vanishing into the darkness. The second clears it. Landing hard, the rider blasts toward a vertical shaft of daylight spearing down from above. The tunnel narrows — ancient gears and colossal stone mechanisms begin turning, triggered by the intrusion. Rotating rings. Crushing slabs.

Seedance 2.0 on Nsketch AI Prompt: Speeder chase across a cliff city (single continuous shot) From a monumental cliffside city carved into stone, the camera dives toward a tiny streak of light ripping along a narrow ledge-road. Lock-on: a speeder hugging the wall at insane speed. The camera slingshots ahead, whips back, then drops tight to the rear thrusters: heat haze, grit snapping off the ledge, warning lights flashing. A collapsing balcony rains debris; the rider snaps a last-inch swerve under a falling arch, then threads through hanging laundry lines and open windows in one fluid line. The camera darts through the same openings, staying glued to the motion. One final bend and sudden calm: the camera blasts outward into a reveal of the city opening onto a boundless waterfall-fed valley, mist turning into rainbow.The rainbow mist lingers for half a second — serenity — then a SHADOW slices across it. From above, two black pursuit speeders dive through the mist, engines screaming. The camera tilts up just as the lead speeder banks hard off the cliff edge, skimming inches above the waterfall’s roaring drop. Spray explodes across the lens but never cuts. The camera rolls with the rider as they plunge straight down the waterfall face — not falling, but riding the vertical air current. Thrusters flare blue-white, stabilizers flickering. Pursuit crafts follow, firing pulse shots that streak through the mist like comets. The rider kicks sideways into a cavern hidden behind the waterfall curtain. The camera punches through liquid light into darkness — bioluminescent moss ignites along the cave walls, revealing an ancient tunnel carved by forgotten hands. Water drips in slow motion as the speed never drops. The camera swings low beneath the speeder, hugging the water-slick stone. Sparks burst as the underside grazes rock. Ahead: a broken bridge spanning a massive underground chasm. No slowdown. The rider guns it. The camera races ahead, flips 180° mid-air as the speeder launches the gap. For a breathless second, only void below — a bottomless abyss glowing faintly with magma veins. Mid-jump, one pursuer clips the edge and spirals down, vanishing into the darkness. The second clears it. Landing hard, the rider blasts toward a vertical shaft of daylight spearing down from above. The tunnel narrows — ancient gears and colossal stone mechanisms begin turning, triggered by the intrusion. Rotating rings. Crushing slabs.

Zara

17,702 次观看 • 4 个月前

🦿Xpeng showed a humanoid robot called IRON whose movement looked so human that the team literally cut it open on stage to prove it is a machine. IRON uses a bionic body with a flexible spine, synthetic muscles, and soft skin so joints and torso can twist smoothly like a person. The system has 82 degrees of freedom in total with 22 in each hand for fine finger control. Compute runs on 3 custom AI chips rated at 2,250 TOPS (Tera Operations Per Second), which is far above typical laptop neural accelerators, so it can handle vision and motion planning on the robot. The AI stack focuses on turning camera input directly into body movement without routing through text, which reduces lag and makes the gait look natural. Xpeng staged the cut-open demo at AI Day in Guangzhou this week, addressing rumors that a performer was inside by exposing internal actuators, wiring, and cooling. Company materials also mention a large physical-world model and a multi-brain control setup for dialogue, perception, and locomotion, hinting at a path from stage demos to service work. Production is targeted for 2026, so near-term tasks will be limited, but the hardware shows a serious step toward human-scale manipulation.

🦿Xpeng showed a humanoid robot called IRON whose movement looked so human that the team literally cut it open on stage to prove it is a machine. IRON uses a bionic body with a flexible spine, synthetic muscles, and soft skin so joints and torso can twist smoothly like a person. The system has 82 degrees of freedom in total with 22 in each hand for fine finger control. Compute runs on 3 custom AI chips rated at 2,250 TOPS (Tera Operations Per Second), which is far above typical laptop neural accelerators, so it can handle vision and motion planning on the robot. The AI stack focuses on turning camera input directly into body movement without routing through text, which reduces lag and makes the gait look natural. Xpeng staged the cut-open demo at AI Day in Guangzhou this week, addressing rumors that a performer was inside by exposing internal actuators, wiring, and cooling. Company materials also mention a large physical-world model and a multi-brain control setup for dialogue, perception, and locomotion, hinting at a path from stage demos to service work. Production is targeted for 2026, so near-term tasks will be limited, but the hardware shows a serious step toward human-scale manipulation.

Rohan Paul

3,802,543 次观看 • 9 个月前

The fascinating concept of Non-Newtonian fluids, which transition from a liquid state to a solid-like state when pressure is applied, has a rich history that spans several centuries. The study and understanding of these peculiar fluids have evolved over time, leading to a wide range of practical applications and scientific insights. One of the earliest references to Non-Newtonian behavior in fluids dates back to the 17th century when Sir Isaac Newton formulated the basic principles of fluid mechanics. Newton's laws of fluid motion primarily applied to Newtonian fluids, which exhibit constant viscosity and flow behavior regardless of the applied force or pressure. However, it soon became apparent that not all fluids behaved in this predictable manner. In the mid-19th century, a scientist named Thomas Andrews made significant contributions to the understanding of Non-Newtonian fluids. Andrews conducted groundbreaking experiments with carbon dioxide, revealing that under high pressure, this gas could transform into a liquid. This observation marked one of the earliest instances of pressure-induced phase changes in fluids. The term "Non-Newtonian" itself was coined in the 20th century to describe fluids that did not adhere to Newton's classical laws of fluid dynamics. These fluids exhibited a variety of behaviors, but one of the most intriguing was their ability to solidify or increase in viscosity when subjected to stress or pressure. One of the most famous examples of such behavior is cornstarch mixed with water, which forms a substance known as "oobleck" that becomes more solid when pressure is applied. In the modern era, Non-Newtonian fluids have found applications in various fields, including food science, engineering, and material science. They are used in products like quicksand, body armor, and even in the development of impact-resistant materials. One of the key insights that emerged from the study of Non-Newtonian fluids is the importance of understanding the relationship between stress and strain, as well as the influence of time-dependent properties on their behavior. This knowledge has led to advancements in rheology, the study of flow and deformation in materials, and has practical implications in areas such as industrial processing, medicine, and the design of everyday products.

The fascinating concept of Non-Newtonian fluids, which transition from a liquid state to a solid-like state when pressure is applied, has a rich history that spans several centuries. The study and understanding of these peculiar fluids have evolved over time, leading to a wide range of practical applications and scientific insights. One of the earliest references to Non-Newtonian behavior in fluids dates back to the 17th century when Sir Isaac Newton formulated the basic principles of fluid mechanics. Newton's laws of fluid motion primarily applied to Newtonian fluids, which exhibit constant viscosity and flow behavior regardless of the applied force or pressure. However, it soon became apparent that not all fluids behaved in this predictable manner. In the mid-19th century, a scientist named Thomas Andrews made significant contributions to the understanding of Non-Newtonian fluids. Andrews conducted groundbreaking experiments with carbon dioxide, revealing that under high pressure, this gas could transform into a liquid. This observation marked one of the earliest instances of pressure-induced phase changes in fluids. The term "Non-Newtonian" itself was coined in the 20th century to describe fluids that did not adhere to Newton's classical laws of fluid dynamics. These fluids exhibited a variety of behaviors, but one of the most intriguing was their ability to solidify or increase in viscosity when subjected to stress or pressure. One of the most famous examples of such behavior is cornstarch mixed with water, which forms a substance known as "oobleck" that becomes more solid when pressure is applied. In the modern era, Non-Newtonian fluids have found applications in various fields, including food science, engineering, and material science. They are used in products like quicksand, body armor, and even in the development of impact-resistant materials. One of the key insights that emerged from the study of Non-Newtonian fluids is the importance of understanding the relationship between stress and strain, as well as the influence of time-dependent properties on their behavior. This knowledge has led to advancements in rheology, the study of flow and deformation in materials, and has practical implications in areas such as industrial processing, medicine, and the design of everyday products.

Historic Vids

2,632,800 次观看 • 2 年前

*Long sigh* Here we go again. E-bikes. Or in this case, what are actually electric dirt bikes. Have you seen these two individuals? We know some of you are tired of hearing about this topic, but we’re determined to keep our community safe, and part of that means identifying the people putting others at risk. This video was taken yesterday around midday near Southlands Mall. One of our officers was patrolling the area when he spotted these two doubled up on what appears to be a modified electric dirt bike. These types of vehicles are not street legal in the City of Aurora and are classified as off-highway vehicles, similar to traditional dirt bikes, ATVs and side-by-sides. Only pedal-assist e-bikes are allowed on roadways and they must follow the same traffic laws as bicycles. These two were not. According to officers and security staff, the pair have repeatedly ridden recklessly through the Southlands area over the past several weeks. They’ve blown through stop signs and red lights, refused to stop for law enforcement and used sidewalks as their personal racetrack. As seen in this video, they eventually fled from officers onto a nearby path. One thing that makes this bike stand out: • The driver wears goggles strapped backward around the helmet • The passenger never wears a helmet • The bike is missing a front fender, which is unusual compared to similar bikes we’ve seen. This behavior creates a serious danger for pedestrians, drivers and everyone trying to safely enjoy the area. We wish this was rare, but incidents involving illegal and reckless e-bike riding continue to increase. Another reminder to parents: Know where your kids are riding. Make sure they understand the rules of the road and the risks that come with these vehicles. Ensure they are wearing the proper safety gear too- including a helmet. If you recognize these individuals or have information, please contact our officer via email at sedwards@auroragov.org. [Media Description: Two individuals riding a e-bike on a sidewalk eluding from police.]

Long sigh Here we go again. E-bikes. Or in this case, what are actually electric dirt bikes. Have you seen these two individuals? We know some of you are tired of hearing about this topic, but we’re determined to keep our community safe, and part of that means identifying the people putting others at risk. This video was taken yesterday around midday near Southlands Mall. One of our officers was patrolling the area when he spotted these two doubled up on what appears to be a modified electric dirt bike. These types of vehicles are not street legal in the City of Aurora and are classified as off-highway vehicles, similar to traditional dirt bikes, ATVs and side-by-sides. Only pedal-assist e-bikes are allowed on roadways and they must follow the same traffic laws as bicycles. These two were not. According to officers and security staff, the pair have repeatedly ridden recklessly through the Southlands area over the past several weeks. They’ve blown through stop signs and red lights, refused to stop for law enforcement and used sidewalks as their personal racetrack. As seen in this video, they eventually fled from officers onto a nearby path. One thing that makes this bike stand out: • The driver wears goggles strapped backward around the helmet • The passenger never wears a helmet • The bike is missing a front fender, which is unusual compared to similar bikes we’ve seen. This behavior creates a serious danger for pedestrians, drivers and everyone trying to safely enjoy the area. We wish this was rare, but incidents involving illegal and reckless e-bike riding continue to increase. Another reminder to parents: Know where your kids are riding. Make sure they understand the rules of the road and the risks that come with these vehicles. Ensure they are wearing the proper safety gear too- including a helmet. If you recognize these individuals or have information, please contact our officer via email at [email protected]. [Media Description: Two individuals riding a e-bike on a sidewalk eluding from police.]

Aurora Police Dept

32,494 次观看 • 2 个月前

When a spacecraft leaves Earth, it doesn’t just fire its engines and head straight to its destination. In many missions, especially those going beyond low Earth orbit, there’s a more subtle and elegant strategy at play, one that uses gravity itself as part of the navigation system. This is often called a gravity assist, or a slingshot maneuver. But in the case of missions like #Artemis II, what’s being used is a closely related idea known as a free-return trajectory. At first glance, it might sound simple: the spacecraft goes to the Moon, loops around it, and comes back. But the physics behind it is anything but simple. Instead of relying on continuous propulsion, the spacecraft follows a carefully calculated path through the gravitational field of the Earth–Moon system. It is launched with just the right speed and direction so that, as it approaches the Moon, the Moon’s gravity bends its trajectory. The spacecraft is effectively flung around the Moon, redirected onto a path that naturally brings it back toward Earth. No major engine burn is needed for the return. Small trajectory corrections may still be required, but gravity does the heavy lifting. That’s the key. This kind of trajectory is not just efficient, it’s also safe. If something goes wrong with the spacecraft’s engines or onboard systems, gravity itself ensures the return. It’s an inherent backup plan, built into the trajectory from the very beginning. The same fundamental idea appears in gravity assists used across the Solar System. When a spacecraft flies past a planet, it can gain or lose speed by exchanging momentum with that planet. From the spacecraft’s point of view, it’s as if it has been accelerated without using fuel. In reality, it has borrowed a tiny amount of orbital energy from the planet itself. That’s how missions like Voyager reached the outer planets, and how probes continue to explore regions far beyond what their onboard fuel alone would allow. But there’s an important distinction. An interplanetary gravity assist is typically used to change speed and direction, often increasing the spacecraft’s energy. A free-return trajectory, like the one used in Artemis II, is designed for something more specific: a path that naturally loops back to Earth without requiring additional propulsion. It’s less about gaining energy, and more about shaping a trajectory that guarantees a return. To understand why this works, it helps to stop thinking in straight lines. In space, motion follows curves defined by gravity. The spacecraft is constantly falling, first toward Earth, then toward the Moon, and then back toward Earth again. What looks like a loop is really a continuous free fall through a changing gravitational landscape. This way of navigating space reveals something deeper. We tend to think of engines as the drivers of motion, but once a spacecraft is on its way, gravity does most of the work. The art of spaceflight is not just about thrust. It’s about knowing when not to use it. #GoodLuck #Artemis NASA Artemis

When a spacecraft leaves Earth, it doesn’t just fire its engines and head straight to its destination. In many missions, especially those going beyond low Earth orbit, there’s a more subtle and elegant strategy at play, one that uses gravity itself as part of the navigation system. This is often called a gravity assist, or a slingshot maneuver. But in the case of missions like #Artemis II, what’s being used is a closely related idea known as a free-return trajectory. At first glance, it might sound simple: the spacecraft goes to the Moon, loops around it, and comes back. But the physics behind it is anything but simple. Instead of relying on continuous propulsion, the spacecraft follows a carefully calculated path through the gravitational field of the Earth–Moon system. It is launched with just the right speed and direction so that, as it approaches the Moon, the Moon’s gravity bends its trajectory. The spacecraft is effectively flung around the Moon, redirected onto a path that naturally brings it back toward Earth. No major engine burn is needed for the return. Small trajectory corrections may still be required, but gravity does the heavy lifting. That’s the key. This kind of trajectory is not just efficient, it’s also safe. If something goes wrong with the spacecraft’s engines or onboard systems, gravity itself ensures the return. It’s an inherent backup plan, built into the trajectory from the very beginning. The same fundamental idea appears in gravity assists used across the Solar System. When a spacecraft flies past a planet, it can gain or lose speed by exchanging momentum with that planet. From the spacecraft’s point of view, it’s as if it has been accelerated without using fuel. In reality, it has borrowed a tiny amount of orbital energy from the planet itself. That’s how missions like Voyager reached the outer planets, and how probes continue to explore regions far beyond what their onboard fuel alone would allow. But there’s an important distinction. An interplanetary gravity assist is typically used to change speed and direction, often increasing the spacecraft’s energy. A free-return trajectory, like the one used in Artemis II, is designed for something more specific: a path that naturally loops back to Earth without requiring additional propulsion. It’s less about gaining energy, and more about shaping a trajectory that guarantees a return. To understand why this works, it helps to stop thinking in straight lines. In space, motion follows curves defined by gravity. The spacecraft is constantly falling, first toward Earth, then toward the Moon, and then back toward Earth again. What looks like a loop is really a continuous free fall through a changing gravitational landscape. This way of navigating space reveals something deeper. We tend to think of engines as the drivers of motion, but once a spacecraft is on its way, gravity does most of the work. The art of spaceflight is not just about thrust. It’s about knowing when not to use it. #GoodLuck #Artemis NASA Artemis

Erika 

234,886 次观看 • 4 个月前

I graduated!!! I earned a Bachelor of Arts in Sociology with a concentration in Psychology, summa cum laude! Five years ago, I started this journey with an eighth-grade education, and even that was from a Scientology school, where critical thinking was discouraged and the quality of instruction was subpar, to say the least. I did not get here alone. Thank you to NYU School of Professional Studies and Angie Kamath. Thank you to everyone who supported me, encouraged me, and believed in me, especially on the days I was not sure I could do this. And there were plenty of those days. To my therapist, who told me not to give up when I was told I likely would not be accepted into a prestigious program. To my tutor, without whom I likely would have given up at the harder points along the way. To all those here who have sent me loving messages on social media. And to everyone else who has cheered me on in person through the ups and the downs of it, it means more than I can put into words. It got me over this finish line of being a student again and graduating. That goal once seemed impossible. To those who have asked me, “Why this? Why now?” I pursued higher education to reclaim a piece of myself. When you come out of a high-control group like Scientology, or even a high-control family, there are parts of you that were never allowed to fully develop. Those parts include your curiosity and your ability and right to question. Education was discouraged because knowledge creates confidence in your ability to trust your own mind and navigate the world. That leads to true independence, and that would never be allowed. I wanted that back. But more than that, I needed to understand. I needed to understand how my mother could have us join Scientology when I was just eight years old, and how my family and I could be part of something like this and stay in it for so long. I needed to understand how these systems work, how they influence people, and how they take hold. Without education, access to real information, and support, people can fall into systems that work against their best interests. Some assume that because they are educated, even highly educated, they would never fall for something like this. But it turns out that is not necessarily true. What many of us are impacted by, but never quite understand, is how high-control groups operate. Many still do not understand how misinformation spreads, and how tribalism and radicalization shape what we think, what we believe, and who and what we trust. Without that awareness, none of us are immune. Today, we are seeing how these forces can influence good people and distort reality. History has shown us that this is not new; it just comes in a different form now. Social media connects us in ways we never imagined, but it also creates echo chambers that reinforce beliefs and justify behavior without question. Real critical thinking is hard when we are fed so much by algorithms designed to appeal to us. In learning and achieving this milestone in my own life, it has helped me take a good, hard look at my own beliefs and ideologies. This journey was about healing for me, but also about figuring out how to help others in whatever way I can in the future. So what is in my future? I am considering continuing my education and possibly pursuing a master’s degree, with the goal of contributing to advocacy and policies that protect people, not systems. For now, I am taking this moment in. I am proud of myself. And I am grateful. Thank you for being on this journey with me.

I graduated!!! I earned a Bachelor of Arts in Sociology with a concentration in Psychology, summa cum laude! Five years ago, I started this journey with an eighth-grade education, and even that was from a Scientology school, where critical thinking was discouraged and the quality of instruction was subpar, to say the least. I did not get here alone. Thank you to NYU School of Professional Studies and Angie Kamath. Thank you to everyone who supported me, encouraged me, and believed in me, especially on the days I was not sure I could do this. And there were plenty of those days. To my therapist, who told me not to give up when I was told I likely would not be accepted into a prestigious program. To my tutor, without whom I likely would have given up at the harder points along the way. To all those here who have sent me loving messages on social media. And to everyone else who has cheered me on in person through the ups and the downs of it, it means more than I can put into words. It got me over this finish line of being a student again and graduating. That goal once seemed impossible. To those who have asked me, “Why this? Why now?” I pursued higher education to reclaim a piece of myself. When you come out of a high-control group like Scientology, or even a high-control family, there are parts of you that were never allowed to fully develop. Those parts include your curiosity and your ability and right to question. Education was discouraged because knowledge creates confidence in your ability to trust your own mind and navigate the world. That leads to true independence, and that would never be allowed. I wanted that back. But more than that, I needed to understand. I needed to understand how my mother could have us join Scientology when I was just eight years old, and how my family and I could be part of something like this and stay in it for so long. I needed to understand how these systems work, how they influence people, and how they take hold. Without education, access to real information, and support, people can fall into systems that work against their best interests. Some assume that because they are educated, even highly educated, they would never fall for something like this. But it turns out that is not necessarily true. What many of us are impacted by, but never quite understand, is how high-control groups operate. Many still do not understand how misinformation spreads, and how tribalism and radicalization shape what we think, what we believe, and who and what we trust. Without that awareness, none of us are immune. Today, we are seeing how these forces can influence good people and distort reality. History has shown us that this is not new; it just comes in a different form now. Social media connects us in ways we never imagined, but it also creates echo chambers that reinforce beliefs and justify behavior without question. Real critical thinking is hard when we are fed so much by algorithms designed to appeal to us. In learning and achieving this milestone in my own life, it has helped me take a good, hard look at my own beliefs and ideologies. This journey was about healing for me, but also about figuring out how to help others in whatever way I can in the future. So what is in my future? I am considering continuing my education and possibly pursuing a master’s degree, with the goal of contributing to advocacy and policies that protect people, not systems. For now, I am taking this moment in. I am proud of myself. And I am grateful. Thank you for being on this journey with me.

Leah Remini

754,037 次观看 • 3 个月前

Alaska. Putin and Trump. The meeting that was both awaited and feared. The outcome. By Roman Alekhin To discuss this further, the key point to understand is this: Two and a half hours behind closed doors is too little for leaders of nuclear powers if they are just starting a conversation—but too much if they were merely posing for cameras. This means the real work happened earlier—quiet, working discussions “behind the door” that never made it into the official communiqué. These are what stopped Trump from imposing secondary sanctions; this is where the exchange of conditions took place, terms that won’t be disclosed until both leaders decide the time is right. I suspect Syria was discussed, as well as the “Trump Bridge” (instead of Zangezur), the Middle East, and much more that isn’t yet visible to the naked eye. The public part? Pure theater. The point wasn’t to negotiate in front of the world or sign something, like Trump did with Armenia and Azerbaijan—minor players, important only tactically. The point was to send a signal: the presidents of Russia and the U.S. are shaking hands and smiling again, no knives behind their backs. This signals that a new reality has arrived, one that Europe, Ukraine, and everyone accustomed to building their worldview around the idea of “Russia’s isolation” will now have to reckon with—including those within our own countries. Trump’s comments on Fox News were deliberately vague—he’s a master at leaving room for maneuver. But the key takeaway is clear: the pressure will now shift from Moscow to Kyiv and Brussels. This is evident even in the final format—not a word about a “no-conditions” ceasefire, which was Europe and Zelensky’s main demand. This means the discussion on a final peace has been postponed, but within a clear framework: Zelensky must exit the war in a way that lets Europe save face. Russia’s red lines have long been clear: non-aligned status for Ukraine, return of Kherson, Zaporizhzhia, Donetsk, and Luhansk regions within their administrative borders (not the frontlines), lifting of sanctions, and real democracy in Ukraine without persecution of the Russian language or the Orthodox Church. These conditions will prolong the conflict for some time. Zelensky will need to stage a fighting retreat to the administrative borders—this will allow Europe to save face. But the logic is already visible: Ukraine’s defeat will be framed not as a “crushing” but as a “peaceful settlement.” Six months—that’s the timeframe in which we’ll see the dynamics. If the front accelerates, the deal is working. If it stalls, not all pieces are in place yet. But the main thing is already done: Russia is back in the game, not through gray negotiating formats but through a handshake on American soil—even if it’s chilly Alaska. (Though we have warm ties to the region, as seen in the wreath-laying for the “Heroes of ALSIB” and the meeting with Archbishop Alexy of Sitka and Alaska.) For the world, this is an image where smiles are worth more than signatures. For Trump—a chance to show he’s the only one who can “make peace.” For Putin—a symbolic victory: Russia is not a besieged enemy but an equal player. For Europe and Ukraine—the beginning of a painful new phase where they’ll have to accept the inevitable. In these talks, there were no winners or losers in Alaska. In Alaska, both presidents won, while those who weren’t there—lost, or at the very least, didn’t win.

Alaska. Putin and Trump. The meeting that was both awaited and feared. The outcome. By Roman Alekhin To discuss this further, the key point to understand is this: Two and a half hours behind closed doors is too little for leaders of nuclear powers if they are just starting a conversation—but too much if they were merely posing for cameras. This means the real work happened earlier—quiet, working discussions “behind the door” that never made it into the official communiqué. These are what stopped Trump from imposing secondary sanctions; this is where the exchange of conditions took place, terms that won’t be disclosed until both leaders decide the time is right. I suspect Syria was discussed, as well as the “Trump Bridge” (instead of Zangezur), the Middle East, and much more that isn’t yet visible to the naked eye. The public part? Pure theater. The point wasn’t to negotiate in front of the world or sign something, like Trump did with Armenia and Azerbaijan—minor players, important only tactically. The point was to send a signal: the presidents of Russia and the U.S. are shaking hands and smiling again, no knives behind their backs. This signals that a new reality has arrived, one that Europe, Ukraine, and everyone accustomed to building their worldview around the idea of “Russia’s isolation” will now have to reckon with—including those within our own countries. Trump’s comments on Fox News were deliberately vague—he’s a master at leaving room for maneuver. But the key takeaway is clear: the pressure will now shift from Moscow to Kyiv and Brussels. This is evident even in the final format—not a word about a “no-conditions” ceasefire, which was Europe and Zelensky’s main demand. This means the discussion on a final peace has been postponed, but within a clear framework: Zelensky must exit the war in a way that lets Europe save face. Russia’s red lines have long been clear: non-aligned status for Ukraine, return of Kherson, Zaporizhzhia, Donetsk, and Luhansk regions within their administrative borders (not the frontlines), lifting of sanctions, and real democracy in Ukraine without persecution of the Russian language or the Orthodox Church. These conditions will prolong the conflict for some time. Zelensky will need to stage a fighting retreat to the administrative borders—this will allow Europe to save face. But the logic is already visible: Ukraine’s defeat will be framed not as a “crushing” but as a “peaceful settlement.” Six months—that’s the timeframe in which we’ll see the dynamics. If the front accelerates, the deal is working. If it stalls, not all pieces are in place yet. But the main thing is already done: Russia is back in the game, not through gray negotiating formats but through a handshake on American soil—even if it’s chilly Alaska. (Though we have warm ties to the region, as seen in the wreath-laying for the “Heroes of ALSIB” and the meeting with Archbishop Alexy of Sitka and Alaska.) For the world, this is an image where smiles are worth more than signatures. For Trump—a chance to show he’s the only one who can “make peace.” For Putin—a symbolic victory: Russia is not a besieged enemy but an equal player. For Europe and Ukraine—the beginning of a painful new phase where they’ll have to accept the inevitable. In these talks, there were no winners or losers in Alaska. In Alaska, both presidents won, while those who weren’t there—lost, or at the very least, didn’t win.

🅰pocalypsis 🅰pocalypseos 🇷🇺 🇨🇳 🅉

13,487 次观看 • 1 年前

Building a personal knowledge base for my agents is increasingly where I spend my time these days. Like Andrej Karpathy, I also use Obsidian for my MD vaults. What's different in my approach is that I curate research papers on a daily basis and have actually tuned a Skill for months to find high-signal, relevant papers. I was reviewing and curating papers manually for some time, but now it's all automated as it has gotten so good at capturing what I consider the best of the best. There are so many papers these days, so this is a big deal. You all get to benefit from that with the papers I feature in my timeline and on DAIR.AI. The papers are indexed using tobi lutke qmd cli tool (all of it in markdown files along with useful metadata). So good for semantic search and surfacing insights, unlike anything out there. I am a visual person, so I then started to experiment with how to leverage this personal knowledge base of research papers inside my new interactive artifact generator (mcp tools inside my agent orchestrator system). The result is what you see in the clip. 100s of papers with all sorts of insights visualized. I keep track of research papers daily, so believe me when I tell you that this system is absolutely insane at surfacing insights. This is the result of months of tinkering on how to index research and leverage agent automations for wikification and robust documentation. But this is just the beginning. The visual artifact (which is interactive too) can be changed dynamically as I please. I can prompt my agent to throw any data at it. I can add different views to the data. Different interactions. I feel like this is the most personalized research system I have ever built and used, and it's not even close. The knowledge that the agents are able to surface from this basic setup is already extremely useful as I experiment with new agentic engineering concepts. I feel like this knowledge layer and the higher-level ones I am working on will allow me to maximize other automation tools like autoresearch. The research is only as good as the research questions. And the research questions are only as good as the insights the agents have access to. Where I am spending time now is on how to make this more actionable. I am obsessed about the search problem here. The automations, autoresearch, ralph research loop (I built one months ago) are easier to build but are only as good as what you feed them. Work in progress. More updates soon. Back to building.

Building a personal knowledge base for my agents is increasingly where I spend my time these days. Like Andrej Karpathy, I also use Obsidian for my MD vaults. What's different in my approach is that I curate research papers on a daily basis and have actually tuned a Skill for months to find high-signal, relevant papers. I was reviewing and curating papers manually for some time, but now it's all automated as it has gotten so good at capturing what I consider the best of the best. There are so many papers these days, so this is a big deal. You all get to benefit from that with the papers I feature in my timeline and on DAIR.AI. The papers are indexed using tobi lutke qmd cli tool (all of it in markdown files along with useful metadata). So good for semantic search and surfacing insights, unlike anything out there. I am a visual person, so I then started to experiment with how to leverage this personal knowledge base of research papers inside my new interactive artifact generator (mcp tools inside my agent orchestrator system). The result is what you see in the clip. 100s of papers with all sorts of insights visualized. I keep track of research papers daily, so believe me when I tell you that this system is absolutely insane at surfacing insights. This is the result of months of tinkering on how to index research and leverage agent automations for wikification and robust documentation. But this is just the beginning. The visual artifact (which is interactive too) can be changed dynamically as I please. I can prompt my agent to throw any data at it. I can add different views to the data. Different interactions. I feel like this is the most personalized research system I have ever built and used, and it's not even close. The knowledge that the agents are able to surface from this basic setup is already extremely useful as I experiment with new agentic engineering concepts. I feel like this knowledge layer and the higher-level ones I am working on will allow me to maximize other automation tools like autoresearch. The research is only as good as the research questions. And the research questions are only as good as the insights the agents have access to. Where I am spending time now is on how to make this more actionable. I am obsessed about the search problem here. The automations, autoresearch, ralph research loop (I built one months ago) are easier to build but are only as good as what you feed them. Work in progress. More updates soon. Back to building.

elvis

465,471 次观看 • 4 个月前

What if any preparations have you seen Iran make ahead of the war? Can you discuss It’s missile capabilities? Any intelligence capabilities? Any surprises it might happen in store? When the 12-day war ended, I estimated that Iran would need about six months to recover, including its nuclear program. Contrary to popular belief, Iran did not lose its entire long-range or medium-range air defense network; while some launchers were damaged, the primary targets of the Israeli strikes were the radar systems. Once the radars were neutralized, Iran successfully hid the bulk of its remaining batteries, leaving much of its arsenal intact. In contrast, short-range systems like the Tor-M1 and domestic variants were heavily engaged against cruise missiles, often being lost or damaged only after their ammunition was completely exhausted. Since then, Iran has worked to rebuild its destroyed radar network and, above all, to implement a genuine counterintelligence doctrine. The Mossad operations against Iranian radars and air defense systems have shaped new perimeter defense and counterintelligence doctrines not only in Iran but in other countries as well. If we look at the quantity of weapons and the organization of armed groups during Iran’s most recent protests, I would say the problem of foreign intelligence operations inside the country remains severe. This seriously threatens much of Iran’s capabilities, and I foresee a wave of sabotage operations as a new war draws closer. Iran has begun receiving collaboration from China across multiple areas,from satellites to internal counterintelligence, but it may still take some time for this to produce tangible results. During the last years, the Mossad relied heavily on cell phones, using SMS for recruitment and accessing device GPS for target location. Iran has since focused intensely on preventing any repetition of this, and on this specific issue, the Chinese appear to have provided support. Although foreign intelligence services have operated extensively inside Iran, the scale of any armed opposition groups is negligible compared to the Iranian armed forces, which could still draw on allied paramilitaries and militias in neighboring countries, including the Houthis. Iran has become a missile power with a stockpile far larger than Western estimates suggest. As early as 1998, Iran was already producing missiles with ranges exceeding 1,000 km, and it has continued doing so ever since, developing 12 to 15 different models in that range - meaning all are capable of reaching Israel. That is nearly 30 years of continuous missile production, resulting in a stockpile of several thousands. Another area where Iran has emerged as a global power is drones, including underwater ones. Iran’s UUVs have evolved rapidly into mass-produced models with integrated AI, and I believe they hold some major surprises in reserve. A key point today is that the AN/TPY-2 radars, which played a critical role in tracking Iranian missiles, would be among the first targets to be engaged. These high-powered X-band radars are the backbone of regional missile defense, providing essential data to THAAD and Patriot batteries. However, because they are large, stationary, and emit high-energy signals, they are highly vulnerable to a first-strike or saturation attack, which would effectively 'blind' the entire defensive network. Obviously, a defense budget of nearly one trillion dollars cannot be compared to Iran’s, but the real question is whether the cost and effort are worth the potential casualties. Even without Israel, the Americans maintain an immense advantage in aerial operations over Iran; however, as I have stated before, this superiority does not translate to the maritime theater.

What if any preparations have you seen Iran make ahead of the war? Can you discuss It’s missile capabilities? Any intelligence capabilities? Any surprises it might happen in store? When the 12-day war ended, I estimated that Iran would need about six months to recover, including its nuclear program. Contrary to popular belief, Iran did not lose its entire long-range or medium-range air defense network; while some launchers were damaged, the primary targets of the Israeli strikes were the radar systems. Once the radars were neutralized, Iran successfully hid the bulk of its remaining batteries, leaving much of its arsenal intact. In contrast, short-range systems like the Tor-M1 and domestic variants were heavily engaged against cruise missiles, often being lost or damaged only after their ammunition was completely exhausted. Since then, Iran has worked to rebuild its destroyed radar network and, above all, to implement a genuine counterintelligence doctrine. The Mossad operations against Iranian radars and air defense systems have shaped new perimeter defense and counterintelligence doctrines not only in Iran but in other countries as well. If we look at the quantity of weapons and the organization of armed groups during Iran’s most recent protests, I would say the problem of foreign intelligence operations inside the country remains severe. This seriously threatens much of Iran’s capabilities, and I foresee a wave of sabotage operations as a new war draws closer. Iran has begun receiving collaboration from China across multiple areas,from satellites to internal counterintelligence, but it may still take some time for this to produce tangible results. During the last years, the Mossad relied heavily on cell phones, using SMS for recruitment and accessing device GPS for target location. Iran has since focused intensely on preventing any repetition of this, and on this specific issue, the Chinese appear to have provided support. Although foreign intelligence services have operated extensively inside Iran, the scale of any armed opposition groups is negligible compared to the Iranian armed forces, which could still draw on allied paramilitaries and militias in neighboring countries, including the Houthis. Iran has become a missile power with a stockpile far larger than Western estimates suggest. As early as 1998, Iran was already producing missiles with ranges exceeding 1,000 km, and it has continued doing so ever since, developing 12 to 15 different models in that range - meaning all are capable of reaching Israel. That is nearly 30 years of continuous missile production, resulting in a stockpile of several thousands. Another area where Iran has emerged as a global power is drones, including underwater ones. Iran’s UUVs have evolved rapidly into mass-produced models with integrated AI, and I believe they hold some major surprises in reserve. A key point today is that the AN/TPY-2 radars, which played a critical role in tracking Iranian missiles, would be among the first targets to be engaged. These high-powered X-band radars are the backbone of regional missile defense, providing essential data to THAAD and Patriot batteries. However, because they are large, stationary, and emit high-energy signals, they are highly vulnerable to a first-strike or saturation attack, which would effectively 'blind' the entire defensive network. Obviously, a defense budget of nearly one trillion dollars cannot be compared to Iran’s, but the real question is whether the cost and effort are worth the potential casualties. Even without Israel, the Americans maintain an immense advantage in aerial operations over Iran; however, as I have stated before, this superiority does not translate to the maritime theater.

Patricia Marins

21,142 次观看 • 5 个月前

Some microbes carry a protein, called SNIPE, that "chops up" phage DNA as it's being injected into the cell. This is a new mechanism for phage defense! CRISPR–Cas and restriction enzymes also evolved to fight against phages, but they work by recognizing sequences. SNIPE works, instead, by sensing "touch." SNIPE is a protein with about 500 amino acids. After it's made by the ribosome, it latches onto ManYZ, two proteins which sit on the cell's inner membrane. (ManYZ is an importer; it brings mannose and other sugars into the cell.) Once attached to ManYZ, SNIPE sits and waits for an invading phage. Some phages, including lambda, actually infect cells by pushing their DNA through this ManYZ channel. Lambda uses its "tail" to reach inside the protein channel, basically, and inject its DNA. When this physical touch happens, though, SNIPE is waiting. As soon as the phage DNA starts entering the cell, and passes through ManYZ and SNIPE, it gets immediately destroyed. This means that SNIPE is the first phage defense system discovered, so far, that uses spatial positioning at the injection site to destroy invaders. But there are caveats, of course. If you untether SNIPE from ManYZ, such that it can freely diffuse through the cell, it will chew up the bacterium's genome. It is not a highly discerning nuclease! Also, SNIPE is not found in most bacteria. A prior pangenome study, which sequenced lots of different microbes, found that roughly a third of well-studied bacterial lineages had at least one member with a SNIPE-like protein. (For this paper, they just ported one of those homologs into an E. coli laboratory strain.) And finally, because SNIPE's mechanism is tightly tied to ManYZ, it cannot be used to defend against phages that enter the cell through different routes. T4 phages, for example, inject their DNA straight through the cell membrane and into the cytoplasm, without interacting with ManYZ. This is a nice basic science paper. Applications TBD. (Just remember that scientists figured out that bacteria had a phage defense system, called CRISPR-Cas, many years before it was repurposed into a gene-editing tool.) P.S. The video below shows how cells with the SNIPE gene (middle row) kill invading phages, and thus continue growing and dividing. Empty vector (top row) refers to bacteria carrying a plasmid with no SNIPE gene; this is a control group. And SNIPE E414A refers to cells which received a mutated SNIPE gene, where the glutamate at position 414 has been changed to an alanine, thus destroying the protein's nuclease activity. These cells also die when they get infected with a phage.

Some microbes carry a protein, called SNIPE, that "chops up" phage DNA as it's being injected into the cell. This is a new mechanism for phage defense! CRISPR–Cas and restriction enzymes also evolved to fight against phages, but they work by recognizing sequences. SNIPE works, instead, by sensing "touch." SNIPE is a protein with about 500 amino acids. After it's made by the ribosome, it latches onto ManYZ, two proteins which sit on the cell's inner membrane. (ManYZ is an importer; it brings mannose and other sugars into the cell.) Once attached to ManYZ, SNIPE sits and waits for an invading phage. Some phages, including lambda, actually infect cells by pushing their DNA through this ManYZ channel. Lambda uses its "tail" to reach inside the protein channel, basically, and inject its DNA. When this physical touch happens, though, SNIPE is waiting. As soon as the phage DNA starts entering the cell, and passes through ManYZ and SNIPE, it gets immediately destroyed. This means that SNIPE is the first phage defense system discovered, so far, that uses spatial positioning at the injection site to destroy invaders. But there are caveats, of course. If you untether SNIPE from ManYZ, such that it can freely diffuse through the cell, it will chew up the bacterium's genome. It is not a highly discerning nuclease! Also, SNIPE is not found in most bacteria. A prior pangenome study, which sequenced lots of different microbes, found that roughly a third of well-studied bacterial lineages had at least one member with a SNIPE-like protein. (For this paper, they just ported one of those homologs into an E. coli laboratory strain.) And finally, because SNIPE's mechanism is tightly tied to ManYZ, it cannot be used to defend against phages that enter the cell through different routes. T4 phages, for example, inject their DNA straight through the cell membrane and into the cytoplasm, without interacting with ManYZ. This is a nice basic science paper. Applications TBD. (Just remember that scientists figured out that bacteria had a phage defense system, called CRISPR-Cas, many years before it was repurposed into a gene-editing tool.) P.S. The video below shows how cells with the SNIPE gene (middle row) kill invading phages, and thus continue growing and dividing. Empty vector (top row) refers to bacteria carrying a plasmid with no SNIPE gene; this is a control group. And SNIPE E414A refers to cells which received a mutated SNIPE gene, where the glutamate at position 414 has been changed to an alanine, thus destroying the protein's nuclease activity. These cells also die when they get infected with a phage.

Niko McCarty.

20,536 次观看 • 5 个月前

Every civilization that worships progress is already walking to its grave. To believe history climbs ever upward is the delusion of a people in decline. Victory comes by remembering who we are. Modernity lives by the noxious falsity that history is a straight ascent, a line rising toward liberty, material security, higher knowledge, and an ever-advancing mastery of the world. Christianity once gave this expectation its sacred form in the promise of salvation at the end of time. The Enlightenment stripped away the divine horizon but kept the same conviction of progress, recasting it as the unfolding of reason, the spread of science, and the emancipation of man from what were once called superstitions. This doctrine, ideological-cum-religion, is now repeated as if it were a law of nature, and those who doubt it are accused of perversity. Yet for most of mankind history was not imagined as a line but as a cycle. The ancients knew that whatever rises must also fall. Hesiod spoke of the decline of mankind through successive ages, from gold into iron. Heraclitus declared that “war is the father of all things,” for creation and destruction are one. Thucydides wrote his account of the Peloponnesian War with the conviction that future wars would resemble it in both their causes and their ruin. Polybius conceptualized the notion of anakyklosis (recurrence), the perpetual rotation of constitutions: monarchy degenerating into tyranny, aristocracy into oligarchy, democracy into mob rule, and from collapse into monarchy again. To them the fate of empires was as certain as the turning of the seasons. Even Machiavelli, on the threshold of modernity, still echoed Polybius when he wrote of the recurrent fortunes of republics. It was into this older vision that Oswald Spengler breathed life in the twentieth century. His great work “The Decline of the West” gave to cyclical history a new form, drawn not from metaphysics but from the morphology of nature. Cultures, he argued, are living organisms. Each is born in a moment of spiritual awakening, grows with an inner law of development, creates great art and form, and then enters upon its winter, when energies are spent, forms petrify, and death becomes inevitable. For this he used the distinction between Kultur (culture), the spring and summer of a people, marked by faith, inward form, and organic vitality, and Zivilisation (civilization), the autumn and winter, marked by intellect without soul, mass life, technical routine, and exhaustion. The West, in his judgment, had already passed from Kultur into Zivilisation. The inner principle of the West, its soul, was what Spengler named Faustian. Every great culture, he held, has a prime symbol that shapes its creations. The Magian world of the Near East saw existence as a cavern, inward and enclosed. The Classical world of Greece and Rome saw the finite, bounded body as the measure of form. The West saw infinite space. The Gothic cathedral, its arches soaring upward into height without measure, was the first revelation of this soul. The sagas of Arthur, Parsifal, and Siegfried, the restless knights of the Grail, and the march of the Crusaders all bore witness to it. The voyages that opened oceans, the maps that encompassed the globe, the infinitesimal calculus of Leibniz and Newton, the endless counterpoint of Bach and the vast harmonies of Wagner, all were the expression of a will to the infinite, a yearning without rest. This Faustian spirit was not content with the near or the familiar. It sought distance, transcendence, and mastery over what lay beyond. It was both creative and dangerous, for it drove men to triumphs unmatched in history but also carried within itself the certainty of overreaching and exhaustion. Spengler’s vision was therefore tragic. The same will that raised Gothic cathedrals and revealed the law of gravitation would in the end dissolve into sterile technique, into cities without form and masses without destiny. For him the West had already entered this stage. Spengler was, in this sense, a Nietzschean. He shared with Nietzsche the rejection of teleology and the denial that history tends toward progress, and he likewise held that life itself is bound to conflict, the agon, in which both rivalry and the will to power are revealed. He spoke of cultures as organisms that arise, strive, and perish, not unlike Nietzsche’s affirmation that life is bound to conflict and that creation and destruction are inseparable. A bit of an aside, when Spengler was buried in Munich in 1936, he was laid to rest with Goethe’s “Faust” and Nietzsche’s “Thus Spoke Zarathustra” placed in his coffin. He saw himself as heir to both, the one the poet of form and destiny, the other the prophet of will and strife. The roots of this Faustian striving reach back beyond Christendom, beyond Greece and Rome, to the Indo-European warrior-aristocrats of the Eurasian steppe. These tribes of the Pontic-Caspian plain lived by horse and chariot, by the defense of herds, and by the honor of their lineage. They were ruled not by despots but by free warriors who regarded their leaders as peers, first among equals, whose authority rested on courage, generosity, and loyalty rather than command alone. Young men were formed in war-bands, associations of companions bound by oath, living by raid and by hunt, pledged to follow their chosen chief even into death. In such companies rivalry and struggle were ceaseless, for each sought to surpass the others in daring, in the ferocity of combat, and in the glory that could outlast life itself. Their poetry and myth remembered these contests not as accidents of circumstance but as the very substance of noble existence, where to fall without renown was worse than death, and to win immortal fame was the highest proof of life. To paraphrase the Hávamál cattle perish and kinsmen perish, but “the fame of a dead man’s deeds” will never perish. From this life issued the earliest epics of Europe. “The Iliad” tells of Achilles choosing immortal fame above a long life. The Mahabharata recounts the deeds of princes who waged war for honor’s sake. Beowulf sings of the Geat who sought a name that death itself could not erase. The Song of Roland praises the knight who dies rather than yield dishonor. The Nibelungenlied recounts the doom of Siegfried and the vengeance of Kriemhild. The Irish Táin Bó Cúailnge tells of Cú Chulainn standing alone against an invading host. The Icelandic sagas, from Njáll’s fate to Egil’s defiance, exalted the warrior who carved his name with blood and song. These were not works of peace or utility but of tragic greatness, affirming life in the face of fate. This ethos carried into the Greek polis, where the agon was institutionalized in public life, from the rivalries of the assembly to the contests of the games, from the tragedies on the stage to the hoplite phalanx on the field of war. The Romans transmuted it into a republic of conquest and law, turning the struggle for honor into dominion over peoples and the codification of order. The medieval knightly orders bound it to Christendom, when crusade and chivalry gave sacred form to ancient valor and set the nobility of Europe against the infidel. The Renaissance hurled it across the oceans, as Cortés in Mexico and da Gama in India sought renown and dominion in uncharted realms. The Scientific Revolution extended it into thought itself, when the telescope, the calculus, and the new physics opened infinite space to inquiry. Each age bore a new expression of the same striving for honor and mastery, the same will to overcome every limit placed before man. Spengler’s judgment was that this will, having conquered the earth, had entered its final exhaustion. What had been vital had become mechanical. The spirit of invention had hardened into sterile routine. The organic life of peoples had dissolved into the masses of world-cities. Yet the question remains whether decline is always fate. Nietzsche believed otherwise. For him life is not a store of energy to be depleted but a force that renews itself wherever men embrace struggle. He saw in the agon not only the cause of decay but the condition of greatness. If men retain the courage to live by strife, decline can be arrested, or at least transfigured into new creation. The Indo-European heritage shows that cultures are not born from comfort but from peril, not from harmony but from contest. The Greeks rose not by suppressing strife but by shaping it into ordered form. Their philosophers contended as their athletes fought, and their poets sought renown as their warriors did. Rome built its empire by the discipline of legions and the law of the strong. The West carried the same spirit into its cathedrals, its voyages, its philosophies, and its sciences. This is Faustian man, the refusal of limits, the yearning for infinity, the restless will to overcome. The cycle of decline may be unavoidable in form, but decline need not mean death. In the biological world exhaustion is followed by regeneration, decay enriches the soil for new growth, and death itself becomes the ground of life. If the West remembers its aristocratic origin, if it accepts strife as its element rather than yielding to the narcotic of progress, rebirth is possible. In Nietzsche’s vision every ending contains the seed of a higher beginning. If Europe wills it, the Faustian soul can be born again. A civilization dies when it abandons struggle; it lives again only when it embraces the agon as its lifeblood. REMEMBER WHO YOU ARE.

Every civilization that worships progress is already walking to its grave. To believe history climbs ever upward is the delusion of a people in decline. Victory comes by remembering who we are. Modernity lives by the noxious falsity that history is a straight ascent, a line rising toward liberty, material security, higher knowledge, and an ever-advancing mastery of the world. Christianity once gave this expectation its sacred form in the promise of salvation at the end of time. The Enlightenment stripped away the divine horizon but kept the same conviction of progress, recasting it as the unfolding of reason, the spread of science, and the emancipation of man from what were once called superstitions. This doctrine, ideological-cum-religion, is now repeated as if it were a law of nature, and those who doubt it are accused of perversity. Yet for most of mankind history was not imagined as a line but as a cycle. The ancients knew that whatever rises must also fall. Hesiod spoke of the decline of mankind through successive ages, from gold into iron. Heraclitus declared that “war is the father of all things,” for creation and destruction are one. Thucydides wrote his account of the Peloponnesian War with the conviction that future wars would resemble it in both their causes and their ruin. Polybius conceptualized the notion of anakyklosis (recurrence), the perpetual rotation of constitutions: monarchy degenerating into tyranny, aristocracy into oligarchy, democracy into mob rule, and from collapse into monarchy again. To them the fate of empires was as certain as the turning of the seasons. Even Machiavelli, on the threshold of modernity, still echoed Polybius when he wrote of the recurrent fortunes of republics. It was into this older vision that Oswald Spengler breathed life in the twentieth century. His great work “The Decline of the West” gave to cyclical history a new form, drawn not from metaphysics but from the morphology of nature. Cultures, he argued, are living organisms. Each is born in a moment of spiritual awakening, grows with an inner law of development, creates great art and form, and then enters upon its winter, when energies are spent, forms petrify, and death becomes inevitable. For this he used the distinction between Kultur (culture), the spring and summer of a people, marked by faith, inward form, and organic vitality, and Zivilisation (civilization), the autumn and winter, marked by intellect without soul, mass life, technical routine, and exhaustion. The West, in his judgment, had already passed from Kultur into Zivilisation. The inner principle of the West, its soul, was what Spengler named Faustian. Every great culture, he held, has a prime symbol that shapes its creations. The Magian world of the Near East saw existence as a cavern, inward and enclosed. The Classical world of Greece and Rome saw the finite, bounded body as the measure of form. The West saw infinite space. The Gothic cathedral, its arches soaring upward into height without measure, was the first revelation of this soul. The sagas of Arthur, Parsifal, and Siegfried, the restless knights of the Grail, and the march of the Crusaders all bore witness to it. The voyages that opened oceans, the maps that encompassed the globe, the infinitesimal calculus of Leibniz and Newton, the endless counterpoint of Bach and the vast harmonies of Wagner, all were the expression of a will to the infinite, a yearning without rest. This Faustian spirit was not content with the near or the familiar. It sought distance, transcendence, and mastery over what lay beyond. It was both creative and dangerous, for it drove men to triumphs unmatched in history but also carried within itself the certainty of overreaching and exhaustion. Spengler’s vision was therefore tragic. The same will that raised Gothic cathedrals and revealed the law of gravitation would in the end dissolve into sterile technique, into cities without form and masses without destiny. For him the West had already entered this stage. Spengler was, in this sense, a Nietzschean. He shared with Nietzsche the rejection of teleology and the denial that history tends toward progress, and he likewise held that life itself is bound to conflict, the agon, in which both rivalry and the will to power are revealed. He spoke of cultures as organisms that arise, strive, and perish, not unlike Nietzsche’s affirmation that life is bound to conflict and that creation and destruction are inseparable. A bit of an aside, when Spengler was buried in Munich in 1936, he was laid to rest with Goethe’s “Faust” and Nietzsche’s “Thus Spoke Zarathustra” placed in his coffin. He saw himself as heir to both, the one the poet of form and destiny, the other the prophet of will and strife. The roots of this Faustian striving reach back beyond Christendom, beyond Greece and Rome, to the Indo-European warrior-aristocrats of the Eurasian steppe. These tribes of the Pontic-Caspian plain lived by horse and chariot, by the defense of herds, and by the honor of their lineage. They were ruled not by despots but by free warriors who regarded their leaders as peers, first among equals, whose authority rested on courage, generosity, and loyalty rather than command alone. Young men were formed in war-bands, associations of companions bound by oath, living by raid and by hunt, pledged to follow their chosen chief even into death. In such companies rivalry and struggle were ceaseless, for each sought to surpass the others in daring, in the ferocity of combat, and in the glory that could outlast life itself. Their poetry and myth remembered these contests not as accidents of circumstance but as the very substance of noble existence, where to fall without renown was worse than death, and to win immortal fame was the highest proof of life. To paraphrase the Hávamál cattle perish and kinsmen perish, but “the fame of a dead man’s deeds” will never perish. From this life issued the earliest epics of Europe. “The Iliad” tells of Achilles choosing immortal fame above a long life. The Mahabharata recounts the deeds of princes who waged war for honor’s sake. Beowulf sings of the Geat who sought a name that death itself could not erase. The Song of Roland praises the knight who dies rather than yield dishonor. The Nibelungenlied recounts the doom of Siegfried and the vengeance of Kriemhild. The Irish Táin Bó Cúailnge tells of Cú Chulainn standing alone against an invading host. The Icelandic sagas, from Njáll’s fate to Egil’s defiance, exalted the warrior who carved his name with blood and song. These were not works of peace or utility but of tragic greatness, affirming life in the face of fate. This ethos carried into the Greek polis, where the agon was institutionalized in public life, from the rivalries of the assembly to the contests of the games, from the tragedies on the stage to the hoplite phalanx on the field of war. The Romans transmuted it into a republic of conquest and law, turning the struggle for honor into dominion over peoples and the codification of order. The medieval knightly orders bound it to Christendom, when crusade and chivalry gave sacred form to ancient valor and set the nobility of Europe against the infidel. The Renaissance hurled it across the oceans, as Cortés in Mexico and da Gama in India sought renown and dominion in uncharted realms. The Scientific Revolution extended it into thought itself, when the telescope, the calculus, and the new physics opened infinite space to inquiry. Each age bore a new expression of the same striving for honor and mastery, the same will to overcome every limit placed before man. Spengler’s judgment was that this will, having conquered the earth, had entered its final exhaustion. What had been vital had become mechanical. The spirit of invention had hardened into sterile routine. The organic life of peoples had dissolved into the masses of world-cities. Yet the question remains whether decline is always fate. Nietzsche believed otherwise. For him life is not a store of energy to be depleted but a force that renews itself wherever men embrace struggle. He saw in the agon not only the cause of decay but the condition of greatness. If men retain the courage to live by strife, decline can be arrested, or at least transfigured into new creation. The Indo-European heritage shows that cultures are not born from comfort but from peril, not from harmony but from contest. The Greeks rose not by suppressing strife but by shaping it into ordered form. Their philosophers contended as their athletes fought, and their poets sought renown as their warriors did. Rome built its empire by the discipline of legions and the law of the strong. The West carried the same spirit into its cathedrals, its voyages, its philosophies, and its sciences. This is Faustian man, the refusal of limits, the yearning for infinity, the restless will to overcome. The cycle of decline may be unavoidable in form, but decline need not mean death. In the biological world exhaustion is followed by regeneration, decay enriches the soil for new growth, and death itself becomes the ground of life. If the West remembers its aristocratic origin, if it accepts strife as its element rather than yielding to the narcotic of progress, rebirth is possible. In Nietzsche’s vision every ending contains the seed of a higher beginning. If Europe wills it, the Faustian soul can be born again. A civilization dies when it abandons struggle; it lives again only when it embraces the agon as its lifeblood. REMEMBER WHO YOU ARE.

Chad Crowley

39,871 次观看 • 10 个月前

This looks like a simple transparent shock absorber filled with oil. But what you are seeing is one of the most destructive phenomena in fluid engineering. This is cavitation in its true form. The white cloud forming beneath the piston is not foam and it is not air. The oil is literally changing from liquid to vapour at room temperature. When the piston moves rapidly, the oil is forced through tiny passages inside the damper. The fluid velocity increases, the local pressure drops, and if it falls below the oil's vapour pressure, the liquid begins to boil without any increase in temperature. The moment the pressure recovers, those microscopic vapour bubbles collapse almost instantly. And that is where the real damage begins. The destructive forces of cavitation is really not understood well by most. A collapsing cavitation bubble creates shockwaves and high-speed microjets that strike nearby surfaces with enormous local forces. Repeated millions of times, these tiny implosions can slowly eat away hardened metals, destroy precision components and reduce the lifespan of expensive machinery across industries. This same invisible phenomenon is one of the biggest challenges in naval engineering. Ship propellers operating under enormous loads can suffer cavitation erosion, losing efficiency while creating underwater noise. For advanced stealth submarines, that noise can become a major problem because cavitation can reveal their position. Decades of research have gone into specialised propeller designs, pump-jets, surface finishes and hydrodynamic optimisation to delay its formation. The same issues affects hydroelectric turbines that convert the energy of entire rivers into electricity, and industrial pumps that move oil, chemicals and water through critical infrastructure around the world. Perhaps the most remarkable part is that after 4-5 decades of advances in metallurgy, coatings and manufacturing, engineers still cannot simply build a material that is immune to cavitation. The solution is not to make stronger metals forever. It is to understand the fluid dynamics so precisely that cavitation is prevented before in those destructive bubbles ever form.

This looks like a simple transparent shock absorber filled with oil. But what you are seeing is one of the most destructive phenomena in fluid engineering. This is cavitation in its true form. The white cloud forming beneath the piston is not foam and it is not air. The oil is literally changing from liquid to vapour at room temperature. When the piston moves rapidly, the oil is forced through tiny passages inside the damper. The fluid velocity increases, the local pressure drops, and if it falls below the oil's vapour pressure, the liquid begins to boil without any increase in temperature. The moment the pressure recovers, those microscopic vapour bubbles collapse almost instantly. And that is where the real damage begins. The destructive forces of cavitation is really not understood well by most. A collapsing cavitation bubble creates shockwaves and high-speed microjets that strike nearby surfaces with enormous local forces. Repeated millions of times, these tiny implosions can slowly eat away hardened metals, destroy precision components and reduce the lifespan of expensive machinery across industries. This same invisible phenomenon is one of the biggest challenges in naval engineering. Ship propellers operating under enormous loads can suffer cavitation erosion, losing efficiency while creating underwater noise. For advanced stealth submarines, that noise can become a major problem because cavitation can reveal their position. Decades of research have gone into specialised propeller designs, pump-jets, surface finishes and hydrodynamic optimisation to delay its formation. The same issues affects hydroelectric turbines that convert the energy of entire rivers into electricity, and industrial pumps that move oil, chemicals and water through critical infrastructure around the world. Perhaps the most remarkable part is that after 4-5 decades of advances in metallurgy, coatings and manufacturing, engineers still cannot simply build a material that is immune to cavitation. The solution is not to make stronger metals forever. It is to understand the fluid dynamics so precisely that cavitation is prevented before in those destructive bubbles ever form.

Ammanichanda

1,187,484 次观看 • 13 天前

99% people aren't aware that the fastest animal on earth spends most of its time doing nothing. There's a reason. A cheetah can hit 70 mph in three seconds. Then it has to stop for twenty minutes. A life lesson hides in there. Your brain wants to believe that extreme speed comes from constant motion, that the fastest creatures are always moving, always hunting, always pushing their biological machinery to the limit. Every nature documentary reinforces this illusion by showing you the chase scenes, the explosive bursts, the moment when physics bends around a spotted blur. What they never show you is what happens next. The cheetah collapses. Its body temperature spikes to dangerous levels. Its heart rate hits 250 beats per minute. Its muscles flood with lactic acid. If another predator appears during those twenty minutes of recovery, the cheetah becomes prey. It cannot run again. It cannot defend itself. It lies there, panting, completely vulnerable, paying the metabolic price for those three seconds of impossible speed. Peak performance is not sustainable performance. The biological systems that produce maximum output operate on completely different principles than the systems that produce steady output. The cheetah's body is an exercise in extreme specialization. Its spine flexes like a spring, storing and releasing kinetic energy with each stride. Its claws work like track spikes, gripping earth during acceleration. Its nasal passages are enlarged to process massive volumes of oxygen during the sprint. Its muscles contain a higher percentage of fast twitch fibers than any other cat. Every adaptation that makes it faster also makes it fragile. The energy economics are brutal. A three second chase burns through roughly 25% of the cheetah's entire daily caloric budget. That sprint costs more energy than some animals use in an entire day of normal activity. The recovery period allows the cheetah's system to clear metabolic waste, restore oxygen levels, and return core temperature to baseline. Without that recovery, the next sprint would be slower. Then slower again. Eventually, the system would shut down entirely. Your laptop operates on the same principle. When you push a processor to maximum speed, it generates heat that requires cooling systems and power management protocols to prevent damage. The CPU cannot maintain peak performance continuously without throttling back to sustainable levels. Intel and AMD engineers understand what cheetah evolution figured out millions of years ago: maximum capability requires careful rationing. Athletic performance follows identical patterns. Sprinters train by running short distances at maximum speed, then resting completely between efforts. Marathon runners train by running longer distances at submaximal speeds. The physiological adaptations that allow Usain Bolt to run 100 meters in 9.58 seconds would prevent him from running a competitive marathon. The adaptations that allow Eliud Kipchoge to run 26.2 miles in just over two hours would prevent him from matching Bolt's top speed. The systems are mutually exclusive. Silicon Valley spent decades trying to ignore this principle. Early startup culture celebrated the idea of constant hustle, permanent availability, 80 hour work weeks as signs of commitment and vision. The mythology suggested that great entrepreneurs outworked their competition by maintaining maximum intensity indefinitely. The data tells a different story. Research on elite performance across domains shows that peak performers work in carefully structured intervals. They push to maximum output during focused periods, then recover completely before the next effort. Musicians practice this way. Athletes train this way. Chess grandmasters study this way. The recovery periods are not interruptions to the work. They are part of the work. Nature does not prioritize constant motion. It prioritizes survival through intelligent energy allocation. The cheetah's hunting strategy maximizes its probability of successful kills while minimizing its risk of metabolic failure. Twenty minutes of vulnerability is acceptable because three seconds of extreme speed often means the difference between eating and starving. The fastest systems in the universe operate this way. Neutron stars can rotate at 700 times per second, but they slow down over time as they lose rotational energy. Supercomputers can process exaflops of calculations per second, but they require massive cooling systems and carefully managed workloads to prevent thermal damage. Even light itself, the fastest thing in the universe, loses energy as it travels through space and time. Speed without recovery is not speed. It is breakdown in slow motion. The cheetah understands something that most humans do not: maximum capability is a tool to be used strategically, not a baseline to be maintained constantly. Those twenty minutes of apparent inactivity should not be considered a weakness. They are preparation for the next moment when impossible speed becomes necessary for survival.

99% people aren't aware that the fastest animal on earth spends most of its time doing nothing. There's a reason. A cheetah can hit 70 mph in three seconds. Then it has to stop for twenty minutes. A life lesson hides in there. Your brain wants to believe that extreme speed comes from constant motion, that the fastest creatures are always moving, always hunting, always pushing their biological machinery to the limit. Every nature documentary reinforces this illusion by showing you the chase scenes, the explosive bursts, the moment when physics bends around a spotted blur. What they never show you is what happens next. The cheetah collapses. Its body temperature spikes to dangerous levels. Its heart rate hits 250 beats per minute. Its muscles flood with lactic acid. If another predator appears during those twenty minutes of recovery, the cheetah becomes prey. It cannot run again. It cannot defend itself. It lies there, panting, completely vulnerable, paying the metabolic price for those three seconds of impossible speed. Peak performance is not sustainable performance. The biological systems that produce maximum output operate on completely different principles than the systems that produce steady output. The cheetah's body is an exercise in extreme specialization. Its spine flexes like a spring, storing and releasing kinetic energy with each stride. Its claws work like track spikes, gripping earth during acceleration. Its nasal passages are enlarged to process massive volumes of oxygen during the sprint. Its muscles contain a higher percentage of fast twitch fibers than any other cat. Every adaptation that makes it faster also makes it fragile. The energy economics are brutal. A three second chase burns through roughly 25% of the cheetah's entire daily caloric budget. That sprint costs more energy than some animals use in an entire day of normal activity. The recovery period allows the cheetah's system to clear metabolic waste, restore oxygen levels, and return core temperature to baseline. Without that recovery, the next sprint would be slower. Then slower again. Eventually, the system would shut down entirely. Your laptop operates on the same principle. When you push a processor to maximum speed, it generates heat that requires cooling systems and power management protocols to prevent damage. The CPU cannot maintain peak performance continuously without throttling back to sustainable levels. Intel and AMD engineers understand what cheetah evolution figured out millions of years ago: maximum capability requires careful rationing. Athletic performance follows identical patterns. Sprinters train by running short distances at maximum speed, then resting completely between efforts. Marathon runners train by running longer distances at submaximal speeds. The physiological adaptations that allow Usain Bolt to run 100 meters in 9.58 seconds would prevent him from running a competitive marathon. The adaptations that allow Eliud Kipchoge to run 26.2 miles in just over two hours would prevent him from matching Bolt's top speed. The systems are mutually exclusive. Silicon Valley spent decades trying to ignore this principle. Early startup culture celebrated the idea of constant hustle, permanent availability, 80 hour work weeks as signs of commitment and vision. The mythology suggested that great entrepreneurs outworked their competition by maintaining maximum intensity indefinitely. The data tells a different story. Research on elite performance across domains shows that peak performers work in carefully structured intervals. They push to maximum output during focused periods, then recover completely before the next effort. Musicians practice this way. Athletes train this way. Chess grandmasters study this way. The recovery periods are not interruptions to the work. They are part of the work. Nature does not prioritize constant motion. It prioritizes survival through intelligent energy allocation. The cheetah's hunting strategy maximizes its probability of successful kills while minimizing its risk of metabolic failure. Twenty minutes of vulnerability is acceptable because three seconds of extreme speed often means the difference between eating and starving. The fastest systems in the universe operate this way. Neutron stars can rotate at 700 times per second, but they slow down over time as they lose rotational energy. Supercomputers can process exaflops of calculations per second, but they require massive cooling systems and carefully managed workloads to prevent thermal damage. Even light itself, the fastest thing in the universe, loses energy as it travels through space and time. Speed without recovery is not speed. It is breakdown in slow motion. The cheetah understands something that most humans do not: maximum capability is a tool to be used strategically, not a baseline to be maintained constantly. Those twenty minutes of apparent inactivity should not be considered a weakness. They are preparation for the next moment when impossible speed becomes necessary for survival.

Darshak Rana ⚡️

18,729 次观看 • 3 个月前

🚨 MERCEDES JUST PUT A MOTOR ONLY 8 CM THICK INTO A CAR THAT CAN HIT 62 MPH IN 2.1 SECONDS. Instead of conventional radial flux motors, Mercedes is betting big on axial flux technology. In these motors, the electromagnetic force flows parallel to the axle, allowing two magnetic rotors to sandwich a central stator in a flat, disc-like layout. The result is dramatically smaller and more powerful. The front motor in the new all-electric Mercedes-AMG GT 4-door Coupe is just 9 cm wide. The rear motors are even thinner at roughly 8 cm each. Despite their tiny size, they help launch the heavy performance car from 0-62 mph in just 2.1 seconds, with a top speed of up to 186 mph. Why this matters: • Axial flux motors are significantly more power-dense and can be up to 50% lighter than traditional designs • Their extreme thinness frees up packaging space in the vehicle for better weight distribution, aerodynamics, or interior room • Mercedes acquired YASA in 2021 and has spent years developing the complex manufacturing processes needed to build them at scale • The technology is debuting in a high-performance AMG model, showing Mercedes is serious about using it in its most demanding cars The deeper implication: While most of the EV conversation focuses on batteries and software, the electric motor itself is undergoing a quiet revolution. Axial flux designs have long been seen as theoretically superior but extremely difficult to manufacture at scale. By solving the production challenges and putting these motors into a real high-performance car, Mercedes is pushing the entire industry forward. The next generation of electric performance cars may not just have bigger batteries they may have fundamentally better motors. We’re watching the physical hardware of EVs evolve as dramatically as the software has. How important do you think motor technology (rather than just battery size) will be for the future of electric performance cars? Follow for more frontier automotive engineering and electric vehicle technology.

🚨 MERCEDES JUST PUT A MOTOR ONLY 8 CM THICK INTO A CAR THAT CAN HIT 62 MPH IN 2.1 SECONDS. Instead of conventional radial flux motors, Mercedes is betting big on axial flux technology. In these motors, the electromagnetic force flows parallel to the axle, allowing two magnetic rotors to sandwich a central stator in a flat, disc-like layout. The result is dramatically smaller and more powerful. The front motor in the new all-electric Mercedes-AMG GT 4-door Coupe is just 9 cm wide. The rear motors are even thinner at roughly 8 cm each. Despite their tiny size, they help launch the heavy performance car from 0-62 mph in just 2.1 seconds, with a top speed of up to 186 mph. Why this matters: • Axial flux motors are significantly more power-dense and can be up to 50% lighter than traditional designs • Their extreme thinness frees up packaging space in the vehicle for better weight distribution, aerodynamics, or interior room • Mercedes acquired YASA in 2021 and has spent years developing the complex manufacturing processes needed to build them at scale • The technology is debuting in a high-performance AMG model, showing Mercedes is serious about using it in its most demanding cars The deeper implication: While most of the EV conversation focuses on batteries and software, the electric motor itself is undergoing a quiet revolution. Axial flux designs have long been seen as theoretically superior but extremely difficult to manufacture at scale. By solving the production challenges and putting these motors into a real high-performance car, Mercedes is pushing the entire industry forward. The next generation of electric performance cars may not just have bigger batteries they may have fundamentally better motors. We’re watching the physical hardware of EVs evolve as dramatically as the software has. How important do you think motor technology (rather than just battery size) will be for the future of electric performance cars? Follow for more frontier automotive engineering and electric vehicle technology.

TheNewPhysics

399,616 次观看 • 1 个月前