We study the random injury outcome caused by multiple flash bang submunitions on a crowd. We are particularly interested in the fluctuations in injury outcome among individual realizations. Previously, to simulate the...We study the random injury outcome caused by multiple flash bang submunitions on a crowd. We are particularly interested in the fluctuations in injury outcome among individual realizations. Previously, to simulate the distribution of the actual number of injured, we developed a comprehensive Monte Carlo model. While the full computational model is important for thorough theoretical investigations, in practical operations, it is desirable to characterize the phenomenological behavior of injury outcome using a concise model with only one or two parameters. Conventionally, the injury outcome is indicated by the average fraction of injured, which is called the risk of significant injury (RSI). The single metric RSI description fails to capture fluctuations in the injury outcome. The number of injured in the crowd is influenced by many random factors: the aiming error of flash bang mortar, the dispersion of submunitions after mortar burst, the amount of acoustic dose reaching individual subjects, and the biovariability of individual subjects’ reactions to a given acoustic dose. We aim to include these random factors properly and concisely. In this study, we represent the random injury outcome as a compound binomial model, in which the hidden injury probability is drawn from a two-parameter model distribution. We formulate and examine six model distributions for the injury probability. The best performer is a mixture of uniform and triangle distributions, parameterized by (RSI, dp) where dp is the standard deviation of the hidden injury probability. This mixture model predicts the behavior of injury outcome with uncertainty, based solely on the two parameters (RSI, dp) in the flash bang description. For example, we can predict the probability of the injury outcome not exceeding a prescribed tolerance. We advocate the adoption of this two-parameter characterization for flash bangs to replace the single-parameter RSI description. Whenever we need to give a high level coarse description of a flash bang situation, we state that the injury risk is represented by (RSI, dp).展开更多
The Current Standard Model of the Universe asserts that the universe is generated from a single Big Bang event followed by inflation. There is no center to this universe, hence, no preferential reference frame to desc...The Current Standard Model of the Universe asserts that the universe is generated from a single Big Bang event followed by inflation. There is no center to this universe, hence, no preferential reference frame to describe the motions of celestial objects. We propose a new, Shell Model of the Universe, which contends that the universe is created from multiple, concentric big bangs. Accordingly, that origin presents itself as a unique, preferential reference frame, which furnishes the simplest description of the motions of galaxies in the cosmos. This is similar in manner to how planetary motion is more straightforwardly described via a sun-centered Solar System rather than an earth-centered one. The appeal of the Shell Model of the Universe lies in its simplistic ability to resolve the paradox of quasars, explain the variability in Hubble’s Constant, and solve the problematic accelerated expansion of the universe.展开更多
2005年,一款冠以“Big Bang”之名的腕表系列出现在大众的视野中,the Big Bang是物理世界中对于物质与时间起源的定义。HUBLOT宇舶表以big bang为名,不难看出其背后深藏的野心,这将是一个足以改变品牌制表理念的腕表系列。如今20年过去,...2005年,一款冠以“Big Bang”之名的腕表系列出现在大众的视野中,the Big Bang是物理世界中对于物质与时间起源的定义。HUBLOT宇舶表以big bang为名,不难看出其背后深藏的野心,这将是一个足以改变品牌制表理念的腕表系列。如今20年过去,Big Bang系列不仅为品牌开创了崭新的发展篇章,更深刻影响了当代制表业的整体发展路径。展开更多
We put forward an enlightening view on repulsive force between antimatter:Antimatter repels each other,and the repulsive force is proportional to the product of their masses and inversely proportional to the square of...We put forward an enlightening view on repulsive force between antimatter:Antimatter repels each other,and the repulsive force is proportional to the product of their masses and inversely proportional to the square of the distance between them;There is no gravitational or anti-gravitational interaction between antimatter and positive matter.As their applications,we explain the Big Bang process in a new light.展开更多
A team of researchers from the Beijing Normal University,the Institute of High Energy Physics(IHEP)under the Chinese Academy of Sciences(CAS),and the National Astronomical Observatories,CAS(NAOC),reported in Nature As...A team of researchers from the Beijing Normal University,the Institute of High Energy Physics(IHEP)under the Chinese Academy of Sciences(CAS),and the National Astronomical Observatories,CAS(NAOC),reported in Nature Astronomy on January 23,2025 their discovery of an X-ray flash about 12.5 billion lightyears away.The signals burst out only 1.2 billion years after the Big Bang,when our 13.8-billion-year-old universe was still in its infancy,and a science satellite swiftly recorded them.展开更多
Based on the mass-energy equation of special relativity and the assumption of the helical motion of light speed in cosmic space,we have theoretically demonstrated the true implications of Planck’s physical quantities...Based on the mass-energy equation of special relativity and the assumption of the helical motion of light speed in cosmic space,we have theoretically demonstrated the true implications of Planck’s physical quantities:Planck length and time represent the step size and period of the helical motion of light speed in the earliest cosmic space following the Big Bang;Planck energy constitutes the minimum energy unit associated with this spatial helical motion;Planck mass is the mass derived from this minimum energy unit.In accordance with the expression of Planck time,we have derived the relationship formula between gravitational acceleration and the speed of light,thereby uncovering an inevitable intrinsic connection between the gravitational field and the electromagnetic field,and indicating that the four fundamental forces in the universe can be unified.Finally,through our spatial helical motion model,we computed the specific values of the four fundamental forces at the moment of strong nuclear force separation.The results reveal that they are in complete agreement with the theoretical calculation values or experimental values in modern physics and quantum mechanics,thereby providing an interesting hint for the unified field theories.展开更多
针对电动化底盘动力转向系统(electric power steering,EPS)的多工况特征和协调不同工况下转向性能的要求,建立了EPS系统动力学模型和汽车三自由度转向模型,建立了EPS系统动态行为描述。设计了EPS系统的切换控制结构,针对助力工况、回...针对电动化底盘动力转向系统(electric power steering,EPS)的多工况特征和协调不同工况下转向性能的要求,建立了EPS系统动力学模型和汽车三自由度转向模型,建立了EPS系统动态行为描述。设计了EPS系统的切换控制结构,针对助力工况、回正工况和阻尼工况分别设计了柔性PID控制算法、模糊PID控制算法和Bang-Bang-PID控制算法,在不同的工况下采用相应的控制算法实时切换和协调控制。设计了1/4试验台架,进行了输入/输出特性试验、输入转矩/电动机电流特性试验和助力特性试验。结果表明:输入/输出特性的左右对称度>90%;输入转矩/电动机电流特性的左右对称度>90%,回程迟滞∈[0.2,0.8],非灵敏区∈[0,2],最大电流∈[30,35];原地转向时的转向轻便性提高了69.6%,5km/h时的转向轻便性提高了56.2%,随着车速的增加,汽车EPS系统的助力效能降低。展开更多
文摘We study the random injury outcome caused by multiple flash bang submunitions on a crowd. We are particularly interested in the fluctuations in injury outcome among individual realizations. Previously, to simulate the distribution of the actual number of injured, we developed a comprehensive Monte Carlo model. While the full computational model is important for thorough theoretical investigations, in practical operations, it is desirable to characterize the phenomenological behavior of injury outcome using a concise model with only one or two parameters. Conventionally, the injury outcome is indicated by the average fraction of injured, which is called the risk of significant injury (RSI). The single metric RSI description fails to capture fluctuations in the injury outcome. The number of injured in the crowd is influenced by many random factors: the aiming error of flash bang mortar, the dispersion of submunitions after mortar burst, the amount of acoustic dose reaching individual subjects, and the biovariability of individual subjects’ reactions to a given acoustic dose. We aim to include these random factors properly and concisely. In this study, we represent the random injury outcome as a compound binomial model, in which the hidden injury probability is drawn from a two-parameter model distribution. We formulate and examine six model distributions for the injury probability. The best performer is a mixture of uniform and triangle distributions, parameterized by (RSI, dp) where dp is the standard deviation of the hidden injury probability. This mixture model predicts the behavior of injury outcome with uncertainty, based solely on the two parameters (RSI, dp) in the flash bang description. For example, we can predict the probability of the injury outcome not exceeding a prescribed tolerance. We advocate the adoption of this two-parameter characterization for flash bangs to replace the single-parameter RSI description. Whenever we need to give a high level coarse description of a flash bang situation, we state that the injury risk is represented by (RSI, dp).
文摘The Current Standard Model of the Universe asserts that the universe is generated from a single Big Bang event followed by inflation. There is no center to this universe, hence, no preferential reference frame to describe the motions of celestial objects. We propose a new, Shell Model of the Universe, which contends that the universe is created from multiple, concentric big bangs. Accordingly, that origin presents itself as a unique, preferential reference frame, which furnishes the simplest description of the motions of galaxies in the cosmos. This is similar in manner to how planetary motion is more straightforwardly described via a sun-centered Solar System rather than an earth-centered one. The appeal of the Shell Model of the Universe lies in its simplistic ability to resolve the paradox of quasars, explain the variability in Hubble’s Constant, and solve the problematic accelerated expansion of the universe.
文摘We put forward an enlightening view on repulsive force between antimatter:Antimatter repels each other,and the repulsive force is proportional to the product of their masses and inversely proportional to the square of the distance between them;There is no gravitational or anti-gravitational interaction between antimatter and positive matter.As their applications,we explain the Big Bang process in a new light.
文摘A team of researchers from the Beijing Normal University,the Institute of High Energy Physics(IHEP)under the Chinese Academy of Sciences(CAS),and the National Astronomical Observatories,CAS(NAOC),reported in Nature Astronomy on January 23,2025 their discovery of an X-ray flash about 12.5 billion lightyears away.The signals burst out only 1.2 billion years after the Big Bang,when our 13.8-billion-year-old universe was still in its infancy,and a science satellite swiftly recorded them.
文摘Based on the mass-energy equation of special relativity and the assumption of the helical motion of light speed in cosmic space,we have theoretically demonstrated the true implications of Planck’s physical quantities:Planck length and time represent the step size and period of the helical motion of light speed in the earliest cosmic space following the Big Bang;Planck energy constitutes the minimum energy unit associated with this spatial helical motion;Planck mass is the mass derived from this minimum energy unit.In accordance with the expression of Planck time,we have derived the relationship formula between gravitational acceleration and the speed of light,thereby uncovering an inevitable intrinsic connection between the gravitational field and the electromagnetic field,and indicating that the four fundamental forces in the universe can be unified.Finally,through our spatial helical motion model,we computed the specific values of the four fundamental forces at the moment of strong nuclear force separation.The results reveal that they are in complete agreement with the theoretical calculation values or experimental values in modern physics and quantum mechanics,thereby providing an interesting hint for the unified field theories.
文摘针对电动化底盘动力转向系统(electric power steering,EPS)的多工况特征和协调不同工况下转向性能的要求,建立了EPS系统动力学模型和汽车三自由度转向模型,建立了EPS系统动态行为描述。设计了EPS系统的切换控制结构,针对助力工况、回正工况和阻尼工况分别设计了柔性PID控制算法、模糊PID控制算法和Bang-Bang-PID控制算法,在不同的工况下采用相应的控制算法实时切换和协调控制。设计了1/4试验台架,进行了输入/输出特性试验、输入转矩/电动机电流特性试验和助力特性试验。结果表明:输入/输出特性的左右对称度>90%;输入转矩/电动机电流特性的左右对称度>90%,回程迟滞∈[0.2,0.8],非灵敏区∈[0,2],最大电流∈[30,35];原地转向时的转向轻便性提高了69.6%,5km/h时的转向轻便性提高了56.2%,随着车速的增加,汽车EPS系统的助力效能降低。
