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A Two-Parameter Description for the Injury Risk of Flash Bangs with Uncertainty
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作者 Hongyun Wang Matthew Simms +2 位作者 George Labaria Wesley A. Burgei Hong Zhou 《American Journal of Operations Research》 2019年第3期79-108,共30页
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
关键词 FLASH bangs Actual Number of INJURED in a Crowd FLUCTUATIONS in the Hidden INJURY Probability Simplified PHENOMENOLOGICAL Models
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The Shell Model of the Universe: A Universe Generated from Multiple Big Bangs
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作者 Tower Chen Zeon Chen 《Journal of Modern Physics》 2016年第7期611-626,共16页
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
关键词 Big Bang Variability in Hubble’s Constant Paradox of Quasars Problematic Accelerated Expansion of the Universe
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HUBLOT Big Bang,腕表新世代
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作者 Chaos 《钟表》 2025年第3期34-37,共4页
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
关键词 发展篇章 HUBLOT 腕表 Big Bang 制表理念
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An enlightening view of the antigravity between antimatter
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作者 MA Ru-yun 《西北师范大学学报(自然科学版)》 2025年第1期10-11,I0002,共3页
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
关键词 UNIVERSE Big Bang ANTIMATTER gravitational force repulsive fore
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Messenger from the Early Universe-Einstein Probe Fuels New Hope for High-redshift GRB Observations
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作者 SONG Jianlan 《Bulletin of the Chinese Academy of Sciences》 2025年第1期51-54,共4页
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
关键词 science satellite big bangwhen early universe high energy physics ihep MESSENGER einstein probe high redshift grb big bang
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NEWS & EVENT
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《钟表》 2025年第4期92-97,共6页
1HUBLOT宇舶全新广告宠猫出镜HUBLOT宇舶表以颠覆传统奢华制表规则闻名于世,始终拒绝墨守成规。品牌以大胆前卫的产品设计向制表传统发起挑战,20年前,Big Bang系列的问世点燃了制表业的变革之火,其大胆融合非传统材质,无视这个品类的传... 1HUBLOT宇舶全新广告宠猫出镜HUBLOT宇舶表以颠覆传统奢华制表规则闻名于世,始终拒绝墨守成规。品牌以大胆前卫的产品设计向制表传统发起挑战,20年前,Big Bang系列的问世点燃了制表业的变革之火,其大胆融合非传统材质,无视这个品类的传统形式。基于勇于革新、大胆不羁的精神,宇舶表及其Big Bang系列推陈出新,持续打造一款又一款令人叹为观止的时计作品。 展开更多
关键词 Big Bang系列 HUBLOT 宇舶表
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The Relationship between Gravitational Acceleration and the Velocity of Light
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作者 Jiang Jian-zhong Zhang Xiang-qian 《Journal of Environmental Science and Engineering(A)》 2025年第5期238-244,共7页
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
关键词 Gravitational acceleration light-speed helical motion of space Planck time unified field theory the Big Bang
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MPL印尼联赛如何成为全世界影响最大的地区联赛
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作者 Nicole 《电子竞技》 2025年第7期40-43,共4页
2025年3月7日,Mobile Legends:Bang Bang(决胜巅峰)印度尼西亚职业联赛(MPL ID)第15赛季在雅加达MPL竞技场拉开帷幕。仅隔一日,ONIC与RRQ Hoshi的小组赛便以1,776,078的峰值观赛人数创下了小组赛收视纪录。这一数据甚至超越了同期英雄... 2025年3月7日,Mobile Legends:Bang Bang(决胜巅峰)印度尼西亚职业联赛(MPL ID)第15赛季在雅加达MPL竞技场拉开帷幕。仅隔一日,ONIC与RRQ Hoshi的小组赛便以1,776,078的峰值观赛人数创下了小组赛收视纪录。这一数据甚至超越了同期英雄联盟全球先锋赛焦点战HLE对阵TES的比赛。 展开更多
关键词 Mobile Legends:Bang Bang MPL ID
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Study of primordial deuterium abundance in Big Bang nucleosynthesis 被引量:2
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作者 Zhi-Lin Shen Jian-Jun He 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期208-215,共8页
Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early universe.Among these,deuterium... Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early universe.Among these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent reactions.To date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational precision.In this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium abundance.We found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H uncertainty.Currently,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He rate.From the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d. 展开更多
关键词 Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method
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Cosmological Redshift Caused by Head-On Collisions with CMB Photons, Not by Expansion of Space
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作者 Gurcharn S. Sandhu Ishaan S. Dhindsa 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1675-1698,共24页
The Big Bang model was first proposed in 1931 by Georges Lemaitre. Lemaitre and Hubble discovered a linear correlation between distances to galaxies and their redshifts. The correlation between redshifts and distances... The Big Bang model was first proposed in 1931 by Georges Lemaitre. Lemaitre and Hubble discovered a linear correlation between distances to galaxies and their redshifts. The correlation between redshifts and distances arises in all expanding models of universe as the cosmological redshift is commonly attributed to stretching of wavelengths of photons propagating through the expanding space. Fritz Zwicky suggested that the cosmological redshift could be caused by the interaction of propagating light photons with certain inherent features of the cosmos to lose a fraction of their energy. However, Zwicky did not provide any physical mechanism to support his tired light hypothesis. In this paper, we have developed the mechanism of producing cosmological redshift through head-on collision between light and CMB photons. The process of repeated energy loss of visual photons through n head-on collisions with CMB photons, constitutes a primary mechanism for producing the Cosmological redshift z. While this process results in steady reduction in the energy of visual photons, it also results in continuous increase in the number of photons in the CMB. After a head-on collision with a CMB photon, the incoming light photon, with reduced energy, keeps moving on its original path without any deflection or scattering in any way. After propagation through very large distances in the intergalactic space, all light photons will tend to lose bulk of their energy and fall into the invisible region of the spectrum. Thus, this mechanism of producing cosmological redshift through gradual energy depletion, also explains the Olbers’s paradox. 展开更多
关键词 REDSHIFT CMBR Big Bang COSMOLOGY Elastic Collisions Tired Light
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The “Dead Universe” Theory: Natural Separation of Galaxies Driven by the Remnants of a Supermassive Dead Universe
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作者 Joel Almeida 《Natural Science》 2024年第6期65-101,共37页
This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This per... This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves. 展开更多
关键词 Dead Universe Theory Heat Death of the Universe Big Bang Theory Universe’s Ultimate Fate Universe Expansion Big Freeze Universe Cosmological Models End of Universe Theories Natural Galaxy Drift Future of the Universe Universe Cooling Down Cosmology and Entropy
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The Big Bang as the Creative Force of the Creation of the Universe
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作者 Avas Khugaev Eugeniya Bibaeva 《Journal of Applied Mathematics and Physics》 2024年第10期3281-3306,共26页
The paper considers the mechanism of the Big Bang energy influence on the creation of space-time fields of four structures of the Universe from the 1st type Ether (the Main Field and three spheres of the Relic). It ex... The paper considers the mechanism of the Big Bang energy influence on the creation of space-time fields of four structures of the Universe from the 1st type Ether (the Main Field and three spheres of the Relic). It explains how the Big Bang energy leads to the processes of “melting” in these structures, generating emergent properties that are different from their properties before the Big Bang. The key role of the Big Bang in completing the process of formation of 70% of DE is emphasized. It is shown that the Big Bang preceded the emergence of the furcation point, which chose several directions for the creation of cosmic matter—it was the combined efforts of these directions that created the visible worlds. The principle of dynamic equilibrium is considered the main criterion of the space-time field, in contrast to other physical fields, which is a necessary prerequisite for the quantization of the gravitational field. A spin particle is introduced, capable of emitting special particles—spitons, the characteristics of which are associated with the topology of the Mobius strip and determine the spinor properties of gravitational fields. The mechanism of interaction of particles of the 2nd type of Ether with the fields of space-time is described, allowing the creation of matter first and then the materiality of visible worlds. At the same time, the role of the “matter-negotiator” in the creation process of visible worlds of the Universe is especially highlighted. Since the new properties of gravitational fields go beyond Einstein’s standard theory of gravity, it is proposed to build a new theory of space-time that generalizes it and has a clear geometric interpretation. The proposed theory is based on the action built on a full set of invariants of the Ricci tensor. Within the framework of the Poincaré theory, the classification of furcation points is considered. The processes at the furcation point are described by the Gauss-Laplace curve, for which the principle of conservation of probability density is introduced when considering the transition at the furcation point to four different directions of development. 展开更多
关键词 Big Bang Furcation Point Space-Time Criterion Mobius Strip Spin-Particle Resonance of Place Matter-Negotiator
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Why the Central Monster in M87 Should Be a Massive DEO Rather than a SMBH?
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作者 Ahmad A. Hujeirat Mauritz Wicker 《Journal of Modern Physics》 2024年第5期537-549,共13页
In this paper, we show that massive envelopes made of highly compressed normal matter surrounding dark objects (DEOs) can curve the surrounding spacetime and make the systems observationally indistinguishable from the... In this paper, we show that massive envelopes made of highly compressed normal matter surrounding dark objects (DEOs) can curve the surrounding spacetime and make the systems observationally indistinguishable from their massive black hole counterparts. DEOs are new astrophysical objects that are made up of entropy-free incompressible supranuclear dense superfluid (SuSu-matter), embedded in flat spacetimes and invisible to outside observers, practically trapped in false vacua. Based on highly accurate numerical modelling of the internal structures of pulsars and massive neutron stars, and in combination with using a large variety of EOSs, we show that the mass range of DEOs is practically unbounded from above: it spans those of massive neutron stars, stellar and even supermassive black holes: thanks to the universal maximum density of normal matter, , beyond which normal matter converts into SuSu-matter. We apply the scenario to the Crab and Vela pulsars, the massive magnetar PSR J0740 6620, the presumably massive NS formed in GW170817, and the SMBHs in Sgr A* and M87*. Our numerical results also reveal that DEO-Envelope systems not only mimic massive BHs nicely but also indicate that massive DEOs can hide vast amounts of matter capable of turning our universe into a SuSu-matter-dominated one, essentially trapped in false vacua. 展开更多
关键词 General Relativity Big Bang Black Holes QSOS Neutron Stars QCD Condensed Matter INCOMPRESSIBILITY SUPERFLUIDITY Super-Conductivity
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Physical Space Was Not Expanding
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作者 Youqi Wang 《Journal of Modern Physics》 2024年第5期634-673,共40页
Plurality of characteristic peaks observed in number density distribution of galaxy redshift reveals that extent of physical space has been finite. Significant portion of observed celestial objects is found pair-wise ... Plurality of characteristic peaks observed in number density distribution of galaxy redshift reveals that extent of physical space has been finite. Significant portion of observed celestial objects is found pair-wise associated, i.e., the observed lights were emitted from one and same luminescent source but seen at different sky directions of observer, which is a unique phenomenon that can occur but only in finite space. Cosmic microwave radiation has always been interpreted as afterglow of Big Bang event. However, such radiation is shown unobservable to current observer if Hubble-Lemaître Correlation is interpreted as caused by receding motion of celestial objects. On the other hand, cosmic radiation can be understood as a common and ordinary phenomenon due to space lens, a unique property only of finite space. From Sloan Digital Sky Survey data, internal diameter of physical space is measured as 2.0 billion light years. If celestial objects were receding, hence physical space was expanding, then characteristic peaks of finite physical space should not appear evenly in number density distribution of redshift of the objects but more sparsely with respect to redshift increase. However, as revealed by the data, locations of the characteristic peaks in the distributions are rather even that do not match the locations as required by receding motion of object. Therefore, as evidenced by the data, physical space was not expanding, at least during the recent 18 billion years. In addition, considerable portion of observed quasars is found sharing a common factor of ~1/2 for their respective gravitation redshifts. 展开更多
关键词 Geometry of Physical Space Big Bang Model ASTROPHYSICS
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ARCADE 2 Spatial Roar, What Theory of Relation Reveals
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作者 Russell Bagdoo 《Journal of Modern Physics》 2024年第5期690-719,共30页
The theory of Relation provides an explanation for the Arcade 2 excess. It assumes that the isotropic radio emission measured by the Arcade 2 Collaboration, which is 5 - 6 times brighter than the expected contribution... The theory of Relation provides an explanation for the Arcade 2 excess. It assumes that the isotropic radio emission measured by the Arcade 2 Collaboration, which is 5 - 6 times brighter than the expected contributions from known extra-galactic sources, is the residue of an immense primitive energy of ordinary matter released by a relativistic bang almost 100 million years after the big bang, which gave the mass-energy the missing gravity to activate contraction. This relativistic bang, via a Lorentz energy transformation, would have released enormous energy held to be the source of the powerful radio noise detected by the NASA researchers. This transformation would have simultaneously triggered the formation of the first stars from dense gas and the reionization of less dense neutral gas. This departs from the idea that continuous reionization began after the formation of the first stars. We emphasize the importance of primordial magnetic fields, which would have generated significant density fluctuations during recombination and acted as a direct seed for cosmic structures. The first stars and galaxies were bathed in strong magnetic fields that gave rise to the radio microwave din (boom) discovered by Arcade 2. These intense magnetic fields alter the trajectory of charged particles zooming near the speed of light, triggering the space roar and emitting radiation that forms a synchrotron radio background. The theory of Relation offers an alternative to the Lambda-CDM cosmological model, which has become the standard model of the big bang, which leads straight to the vacuum catastrophe. 展开更多
关键词 Arcade 2 Excess Relativistic Bang Theory of Relation Lorentz Energy Transformation Cosmic Statics Cosmic Boom Synchrotron Radio Background Primordial Magnetic Fields
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货物运输时间成本研究 被引量:9
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作者 杨黎霞 郑波 张异 《价值工程》 2015年第22期189-190,共2页
货物在运输时所消耗的时间,不仅会对货物本身的价值产生影响,也会增加一定的额外费用。额外费用的总和,在理论上就是货物在运输过程中,消耗的时间价值。本文构建了运输时间成本模型,并结合实际的案例进行分析,得出综合考虑运输时间成本... 货物在运输时所消耗的时间,不仅会对货物本身的价值产生影响,也会增加一定的额外费用。额外费用的总和,在理论上就是货物在运输过程中,消耗的时间价值。本文构建了运输时间成本模型,并结合实际的案例进行分析,得出综合考虑运输时间成本与只考虑运价的时候运输方式选择上有所差别,也印证了某些货物在实际运作时不是选择运价最低的运输方式的现象。 展开更多
关键词 货物运输 运输时间成本 Alford—bangs模型
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关于浙藏敦114号《肃州府主致沙州令公书状》的几个问题
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作者 陆离 《青海民族大学学报(社会科学版)》 CSSCI 北大核心 2021年第1期134-139,共6页
浙藏敦114号藏文文书记载了五代归义军节度使曹议金时期肃州政权与归义军的关系,龙家、柔然、回鹘等部族在肃州一带活动的情况以及肃州地区的佛教信仰状况。汉藏文书的记载显示了柔然(ru ru)部族活动在瓜沙西北伊州附近,晚唐五代时期自... 浙藏敦114号藏文文书记载了五代归义军节度使曹议金时期肃州政权与归义军的关系,龙家、柔然、回鹘等部族在肃州一带活动的情况以及肃州地区的佛教信仰状况。汉藏文书的记载显示了柔然(ru ru)部族活动在瓜沙西北伊州附近,晚唐五代时期自漠北迁入,龙家(lung’bangs)部族自8世纪末吐蕃占领西域焉耆后即迁入河西甘、凉地区,与羌(dor po,党项)毗邻而居,晚唐五代时期又迁入肃州,成为肃州主要部族。 展开更多
关键词 柔然(ru ru) 龙家(lung’bangs) 归义军 肃州
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一种具有中点平衡功能的三电平异步电机直接转矩控制方法 被引量:25
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作者 林磊 邹云屏 +3 位作者 王展 金红元 邹旭东 钟和清 《中国电机工程学报》 EI CSCD 北大核心 2007年第3期46-50,共5页
对三电平逆变器供电异步电机直接转矩控制(DTC)系统进行了研究。以固定合成矢量为基础,提出了一种三电平异步电机DTC控制方法,并使用基于三相输出电流方向及中点不平衡方向检测的中点平衡Bang-Bang控制方法来控制中点电位平衡。使用文中... 对三电平逆变器供电异步电机直接转矩控制(DTC)系统进行了研究。以固定合成矢量为基础,提出了一种三电平异步电机DTC控制方法,并使用基于三相输出电流方向及中点不平衡方向检测的中点平衡Bang-Bang控制方法来控制中点电位平衡。使用文中的DTC方法,可以抑制三电平直流侧中点不平衡,限制输出电压dv/dt,减小开关损耗,同时获得良好的电机调速特性。实验结果证明了该控制方法的可行性。 展开更多
关键词 异步电机 三电平逆变器 直接转矩控制 固定合成矢量 中点平衡 Bang—Bang控制
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反电势算法的永磁同步电机无位置传感器自启动过程 被引量:51
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作者 王子辉 叶云岳 《电机与控制学报》 EI CSCD 北大核心 2011年第10期36-42,共7页
提出一种基于反电势积分法的永磁同步电机无位置传感器自启动控制策略,其启动阶段采用速度开环、电流闭环控制,正常运行阶段以速度-电流双闭环控制,采用id=0,iq=常数的控制方式。状态转换过程中,以估测器估测的转子位置与给定坐标系的... 提出一种基于反电势积分法的永磁同步电机无位置传感器自启动控制策略,其启动阶段采用速度开环、电流闭环控制,正常运行阶段以速度-电流双闭环控制,采用id=0,iq=常数的控制方式。状态转换过程中,以估测器估测的转子位置与给定坐标系的相位差值为参考变量,对定子轴电流进行控制,以使相位差值收敛于0,从而实现速度、转矩的平顺切换。实验不仅验证了反电势积分估测法的有效性,也对状态切换时刻基于bang-bang控制策略和PID控制策略的定子电流过渡过程进行了比较研究。实验结果表明,该自启动策略能够使电机从零负载到最大负载条件下平顺可靠地加速到额定运行状态,控制方式的切换过程平滑无冲击。基于无位置传感器算法的双闭环控制系统具有良好的动态运行性能。 展开更多
关键词 永磁同步电机 矢量控制 状态切换 角度-电流闭环 bang—bang控制 PID控制
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基于磁致伸缩作动器的拉索主动控制与多级Bang-Bang控制仿真分析 被引量:6
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作者 王修勇 孟庆甲 +2 位作者 郭雪涛 孙洪鑫 禹见达 《地震工程与工程振动》 CSCD 北大核心 2014年第2期161-166,共6页
拉索容易在外部激励下发生大幅振动,采用磁致伸缩作动器提供轴向控制力进行拉索振动控制是一种新的方法。本文建立了拉索-磁致伸缩作动器动力方程,通过实验得到了磁致伸缩作动器力-磁关系,提出了应用磁致伸缩作动器的剪切型线性二次型... 拉索容易在外部激励下发生大幅振动,采用磁致伸缩作动器提供轴向控制力进行拉索振动控制是一种新的方法。本文建立了拉索-磁致伸缩作动器动力方程,通过实验得到了磁致伸缩作动器力-磁关系,提出了应用磁致伸缩作动器的剪切型线性二次型最优控制(CLQR)策略、多级BangBang控制策略,并进行了拉索振动控制仿真分析。结果表明,磁致伸缩作动器具有良好的减振效果。 展开更多
关键词 拉索 磁致伸缩作动器 剪切型线性二次型最优控制 多级Bang—Bang控制 仿真
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