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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric magnetic Lorentz Invariant Hertzian Vector Point Potential field Density Phase Flow Attraction REPULSION Shell theorem Ehrenfest VIRIAL normalization Harmonic Oscillator
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Seeking the Source of Transience for a Unique Magnetic Field Pattern That Completely Dissolves Cancer Cells <i>in Vitro</i>
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作者 Lukasz M. Karbowski Nirosha J. Murugan +1 位作者 Stanley A. Koren Michael A. Persinger 《Journal of Biomedical Science and Engineering》 2015年第8期531-543,共13页
Purpose: Exposure to a particular pattern of weak (~3 to 5 μT) magnetic fields produced by computer-generated point durations within three-dimensions completely dissolved malignant cancer cells but not healthy cells.... Purpose: Exposure to a particular pattern of weak (~3 to 5 μT) magnetic fields produced by computer-generated point durations within three-dimensions completely dissolved malignant cancer cells but not healthy cells. Biomolecular analyses and confocal microscopy indicated excessive expansion followed by contraction contributed to the “explosion” of the cell. However, after months of replicable effects, the phenomenon slowly ceased. Considering the potency of the complete dissolution of cancer cell lines after 5 days of 6.5-hour daily exposures and the implications for human treatment, the potential source of the disappearance of the effect was pursued by summarizing all of the 50 experiments and assessing the likely etiologies. Materials and Methods: B16-BL6, MDAMB 231 and MCF7 malignant cells and HSG, a non-malignant cell line, were exposed to a sham-field condition or to a specific pattern of computer-generated magnetic fields produced from converting different voltages, each with point durations of 3 ms to 3-D magnetic fields. Conclusion: The specific serial presentation of the two field patterns (one frequency modulated;the other amplitude and frequency modulated) completely dissolved malignant cells but not normal cells within a “zone” within the exposure volume at the conjunction of the three planes of the applied magnetic fields. The affected cells underwent massive melanin production, expansion, contraction and “beading” of submembrane actin structures before fragmentation within this zone. However, this powerful all-or-none phenomenon may have been disrupted by moving the cells, excess mechanical agitation during exposure, or non-optimal point durations of the field parameters. Indirect effects from communication signals (WIFI) through line currents that operated the incubators could not be excluded. 展开更多
关键词 Cancer CELLS normal CELLS Point Duration magnetic fieldS Dissolution Effect MicroTesla Intensities Melanoma M16 CELLS Three-Dimensional Conjunctive fieldS
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Investigation of Shock Waves in Non-Ideal Gas under the Action of Magnetic Field
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作者 Kanti Pandey Praveen Prakash Pathak 《Advances in Pure Mathematics》 2017年第10期583-596,共14页
In present paper, certain aspect of shock wave in non-ideal gas, when magnetic field is orthogonal to the trajectories of the gas particles and electrical conductivity is taken to be infinite, is investigated. Conside... In present paper, certain aspect of shock wave in non-ideal gas, when magnetic field is orthogonal to the trajectories of the gas particles and electrical conductivity is taken to be infinite, is investigated. Considering one-dimensional unsteady non-planer motion, basic equations, its general solution and formation of shock-wave, conservation laws and jumps conditions, variation of area of non-uniform cross section and analytical solution of strong non planer shock is obtained. 展开更多
关键词 SHOCK-WAVES NON-IDEAL GASES magnetic field
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The Mars orbiter magnetometer of Tianwen-1:in-flight performance and first science results 被引量:1
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作者 YuMing Wang TieLong Zhang +17 位作者 GuoQiang Wang SuDong Xiao ZhuXuan Zou Long Cheng ZongHao Pan Kai Liu XinJun Hao YiRen Li ManMing Chen ZhouBin Zhang Wei Yan ZhenPeng Su ZhiYong Wu ChengLong Shen YuTian Chi MengJiao Xu JingNan Guo Yang Du 《Earth and Planetary Physics》 EI CSCD 2023年第2期216-228,共13页
The Mars Orbiter MAGnetometer(MOMAG)is a scientific instrument onboard the orbiter of China’s first mission for Mars—Tianwen-1.Since November 13,2021,it has been recording magnetic field data from the solar wind to ... The Mars Orbiter MAGnetometer(MOMAG)is a scientific instrument onboard the orbiter of China’s first mission for Mars—Tianwen-1.Since November 13,2021,it has been recording magnetic field data from the solar wind to the magnetic pile-up region surrounding Mars.Here we present its in-flight performance and first science results,based on its first one and one-half months’data.Comparing these early MOMAG observations to the magnetic field data in the solar wind from NASA’s Mars Atmosphere and Volatile EvolutioN(MAVEN)mission,we report that the MOMAG magnetic field data are at the same level in magnitude,and describe the same magnetic structures with similar variations in three components.We recognize 158 clear bow shock(BS)crossings in these MOMAG data;their locations match well statistically with the modeled average BS.We also identify and compare five pairs of datasets collected when Tianwen-1’s orbiter and the MAVEN probe made simultaneous BS crossings.These BS crossings confirm the global shape of modeled BS,as well as the south-north asymmetry of the Martian BS.Two cases presented in this paper suggest that the BS is probably more dynamic at flank than near the nose.So far,MOMAG performs well,and provides accurate magnetic field vectors.MOMAG is continuously scanning the magnetic field surrounding Mars.Data from MOMAG’s measurements complement data from MAVEN and will undoubt edly advance our understanding of the plasma environment of Mars. 展开更多
关键词 MARS magnetic field Tianwen-1 magnetometer bow shock
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Normal tension glaucoma: from the brain to the eye or the inverse? 被引量:6
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作者 Hui-Jun Zhang Xue-Song Mi Kwok-Fai So 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第11期1845-1850,共6页
Glaucoma is a chronic, progressive optic neuropathy characterized by the loss of peripheral vision first and then central vision. Clinically, normal tension glaucoma is considered a special subtype of glaucoma, in whi... Glaucoma is a chronic, progressive optic neuropathy characterized by the loss of peripheral vision first and then central vision. Clinically, normal tension glaucoma is considered a special subtype of glaucoma, in which the patient’s intraocular pressure is within the normal range, but the patient experiences typical glaucomatous changes. However, increasing evidence has challenged the traditional pathophysiological view of normal tension glaucoma, which is based only on intraocular pressure, and breakthroughs in central nervous system imaging may now greatly increase our knowledge about the mechanisms underlying normal tension glaucoma. In this article, we review the latest progress in understanding the pathogenesis of normal tension glaucoma and in developing imaging techniques to detect it, to strengthen the appreciation for the connection between normal tension glaucoma and the brain. 展开更多
关键词 NERVE REGENERATION normal tension GLAUCOMA open angle GLAUCOMA NEURODEGENERATIVE diseases visual field CEREBROSPINAL fluid pressure IMAGING techniques pathogenesis magnetic resonance IMAGING diffusion tensor IMAGING metabolic changes neural REGENERATION
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Formation of the bow shock indentation: MHD simulation results 被引量:3
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作者 BaoHang Qu JianYong Lu +3 位作者 Ming Wang HuanZhi Yuan Yue Zhou HanXiao Zhang 《Earth and Planetary Physics》 CSCD 2021年第3期259-269,共11页
Simulation results from a global magnetohydrodynamic(MHD)model are used to examine whether the bow shock has an indentation and characterize its formation conditions,as well as its physical mechanism.The bow shock is ... Simulation results from a global magnetohydrodynamic(MHD)model are used to examine whether the bow shock has an indentation and characterize its formation conditions,as well as its physical mechanism.The bow shock is identified by an increase in plasma density of the solar wind,and the indentation of the bow shock is determined by the shock flaring angle.It is shown that when the interplanetary magnetic field(IMF)is southward and the Alfvén Mach number(Mα)of solar wind is high(>5),the bow shock indentation can be clearly determined.The reason is that the outflow region of magnetic reconnection(MR)that occurs in the low latitude area under southward IMF blocks the original flow in the magnetosheath around the magnetopause,forming a high-speed zone and a low-speed zone that are upstream and downstream of each other.This structure hinders the surrounding flow in the magnetosheath,and the bow shock behind the structure widens and forms an indentation.When Mαis low,the magnetosheath is thicker and the disturbing effect of the MR outflow region is less obvious.Under northward IMF,MR occurs at high latitudes,and the outflow region formed by reconnection does not block the flow inside the magnetosheath,thus the indentation is harder to form.The study of the conditions and formation process of the bow shock indentation will help to improve the accuracy of bow shock models. 展开更多
关键词 indentation of bow shock global MHD simulation interplanetary magnetic field Bz Alfvén Mach number
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Ensembling Neural Networks for User’s Indoor Localization Using Magnetic Field Data from Smartphones 被引量:1
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作者 Imran Ashraf Soojung Hur +1 位作者 Yousaf Bin Zikria Yongwan Park 《Computers, Materials & Continua》 SCIE EI 2021年第8期2597-2620,共24页
Predominantly the localization accuracy of the magnetic field-based localization approaches is severed by two limiting factors:Smartphone heterogeneity and smaller data lengths.The use of multifarioussmartphones cripp... Predominantly the localization accuracy of the magnetic field-based localization approaches is severed by two limiting factors:Smartphone heterogeneity and smaller data lengths.The use of multifarioussmartphones cripples the performance of such approaches owing to the variability of the magnetic field data.In the same vein,smaller lengths of magnetic field data decrease the localization accuracy substantially.The current study proposes the use of multiple neural networks like deep neural network(DNN),long short term memory network(LSTM),and gated recurrent unit network(GRN)to perform indoor localization based on the embedded magnetic sensor of the smartphone.A voting scheme is introduced that takes predictions from neural networks into consideration to estimate the current location of the user.Contrary to conventional magnetic field-based localization approaches that rely on the magnetic field data intensity,this study utilizes the normalized magnetic field data for this purpose.Training of neural networks is carried out using Galaxy S8 data while the testing is performed with three devices,i.e.,LG G7,Galaxy S8,and LG Q6.Experiments are performed during different times of the day to analyze the impact of time variability.Results indicate that the proposed approach minimizes the impact of smartphone variability and elevates the localization accuracy.Performance comparison with three approaches reveals that the proposed approach outperforms them in mean,50%,and 75%error even using a lesser amount of magnetic field data than those of other approaches. 展开更多
关键词 Indoor localization magnetic field data long short term memory network data normalization gated recurrent unit network deep learning
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Relation of the Coercivity with the Grain Alignment Degree in Nd-Fe-B Sintermagnets
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作者 高汝伟 章亚明 +4 位作者 李华 姜寿亭 周寿增 李佛标 张黎东 《Journal of Rare Earths》 SCIE EI CAS CSCD 1994年第4期264-267,共4页
The experimental results show that the coercivity of Nd-Fe-B sintermagnet decreases with increasing of the grain alignment degree of the magnets (i.e. decreasing of the orientation distribution coefficient σ).The coe... The experimental results show that the coercivity of Nd-Fe-B sintermagnet decreases with increasing of the grain alignment degree of the magnets (i.e. decreasing of the orientation distribution coefficient σ).The coercivities of the magnets with different orientation degree are calculated based on the pinning,nucleation and starting field theory,respectively.The comparison of the calculated values with the experimental results shows that the theoretical results are deviating from the experiments seriously for both pinning mechanism and nucleation mechanism. In contrast with that,the calculated values based on the starting field theory are in good agreement with the experimental results. 展开更多
关键词 Orientation magnetic field Grain alignment degree normalized coercivity Starting field Expanding field
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Rotational Effect on the Propagation of Waves in a Magneto-Micropolar Thermoelastic Medium
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作者 A.M.Abd-Alla S.M.Abo-Dahab +1 位作者 M.A.Abdelhafez A.M.Farhan 《Computers, Materials & Continua》 SCIE EI 2021年第10期205-220,共16页
The present paper aims to explore how the magnetic field,ramp parameter,and rotation affect a generalized micropolar thermoelastic medium that is standardized isotropic within the half-space.By employing normal mode a... The present paper aims to explore how the magnetic field,ramp parameter,and rotation affect a generalized micropolar thermoelastic medium that is standardized isotropic within the half-space.By employing normal mode analysis and Lame’s potential theory,the authors could express analytically the components of displacement,stress,couple stress,and temperature field in the physical domain.They calculated such manners of expression numerically and plotted the matching graphs to highlight and make comparisons with theoretical findings.The highlights of the paper cover the impacts of various parameters on the rotating micropolar thermoelastic half-space.Nevertheless,the non-dimensional temperature is not affected by the rotation and the magnetic field.Specific attention is paid to studying the impact of the magnetic field,rotation,and ramp parameter of the distribution of temperature,displacement,stress,and couple stress.The study highlighted the significant impact of the rotation,magnetic field,and ramp parameter on the micropolar thermoelastic medium.In conclusion,graphical presentations were provided to evaluate the impacts of different parameters on the propagation of plane waves in thermoelastic media of different nature.The study may help the designers and engineers develop a structural control system in several applied fields. 展开更多
关键词 magnetic field MICROPOLAR theRMOELASTIC ROTATION ramp parameter normal mode analysis
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Thomson effect with hyperbolic two-temperature on magneto-thermo-visco-elasticity 被引量:1
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作者 A.M.ALHARBI M.I.A.OTHMAN H.M.ATEF 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第9期1311-1326,共16页
The study considers a homogeneous isotropic thermo-visco-elastic solid with hyperbolic two-temperature to cope up with its two-dimensional(2 D)deformations.The heat conduction equation is influenced by the Thomson coe... The study considers a homogeneous isotropic thermo-visco-elastic solid with hyperbolic two-temperature to cope up with its two-dimensional(2 D)deformations.The heat conduction equation is influenced by the Thomson coefficient.Lord-Shulman’s theory is used to modify the basic governing equations.A method called"normal mode analysis"is utilized to attain the magnetic field,stress,conductive and thermodynamic temperature,and displacement components.Also,a number of numerical calculations are performed and discussed to understand the impact of hyperbolic two-temperatures,Thomson parameter,and viscosity on the material mentioned above. 展开更多
关键词 thermo-visco-elasticity magnetic field hyperbolic two-temperature Lord-Shulman’s theory Thomson coefficient normal mode analysis
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Magneto-Thermoelasticity with Thermal Shock Considering Two Temperatures and LS Model
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作者 F.S.Bayones S.M.Abo-Dahab +2 位作者 N.S.Hussein A.M.Abd-Alla H.A.Alshehri 《Computers, Materials & Continua》 SCIE EI 2022年第2期3365-3381,共17页
The present investigation is intended to demonstrate the magnetic field,relaxation time,hydrostatic initial stress,and two temperature on the thermal shock problem.The governing equations are formulated in the context... The present investigation is intended to demonstrate the magnetic field,relaxation time,hydrostatic initial stress,and two temperature on the thermal shock problem.The governing equations are formulated in the context of Lord-Shulman theory with the presence of bodily force,two temperatures,thermal shock,and hydrostatic initial stress.We obtained the exact solution using the normal mode technique with appropriate boundary conditions.The field quantities are calculated analytically and displayed graphically under thermal shock problem with effect of external parameters respect to space coordinates.The results obtained are agreeing with the previous results obtained by others when the new parameters vanish.The results indicate that the effect of magnetic field and initial stress on the conductor temperature,thermodynamic temperature,displacement and stress are quite pronounced.In order to illustrate and verify the analytical development,the numerical results of temperature,displacement and stress are carried out and computer simulated results are presented graphically.This study helpful in the development of piezoelectric devices. 展开更多
关键词 theRMOELASTIC thermal shock initial stress two temperatures magnetic field relaxation time
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Experiment on low-frequency electromagnetic waves propagating in shock-tube-generated magnetized cylindrical enveloping plasma
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作者 Shaoshuai GUO Kai XIE +2 位作者 Bin SUN Ruoyao XI Yan LIU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第7期67-77,共11页
We propose a method of applying a static magnetic field to reduce the attenuation of the magnetic field component(SH) of low-frequency electromagnetic(LF EM) waves in dense plasma. The principle of this method is to a... We propose a method of applying a static magnetic field to reduce the attenuation of the magnetic field component(SH) of low-frequency electromagnetic(LF EM) waves in dense plasma. The principle of this method is to apply a static magnetic field to limit electron movement, thereby increasing the equivalent resistance and thus reducing the induced current and SH. We consider the static magnetic field acting on the plasma of the entire induced current loop rather than on the local plasma, where the induced current is excited by the magnetic field component of LF EM waves. Analytical expressions of SH suitable for magnetized cylindrical enveloping plasma are derived by adopting an equivalent circuit approach, by which SHis calculated with respect to various plasma parameter settings. The results show that SH can be reduced under a static magnetic field and the maximum magnetic field strength that mitigates blackout is less than 0.1 T. Experiments in which LF EM waves propagate in a shock-tubegenerated magnetized cylindrical enveloping plasma are also conducted. SH measured under the magnetic field(the magnetic field strength B0 acting on the magnetic field probe was about0.06 T) reduces at f=10 MHz and f=30 MHz when ne≈1.9×1013 cm-3, which is consistent with theoretical results. The verification of the theory thus suggests that applying a static magnetic field with a weak magnetic field has the potential to improve the transmission capacity of LF EM waves in dense plasma. 展开更多
关键词 static magnetic field shock tube low-frequency electromagnetic waves cylindrical enveloping plasma
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Comparison between magnetic coplanarity and MVA methods in determining the normal of Venusian bow shock
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作者 SHAN LiCan LU QuanMing +4 位作者 ZHANG TieLong GAO XinLiang HUANG Can SU YanQing WANG Shui 《Chinese Science Bulletin》 SCIE EI CAS 2013年第20期2469-2472,共4页
With the measurements of magnetic field of Venus Express (VEX), magnetic coplanarity and minimum variance analysis (MVA) methods are analyzed and their validity is tested to determine the normal of Venusian bow shocks... With the measurements of magnetic field of Venus Express (VEX), magnetic coplanarity and minimum variance analysis (MVA) methods are analyzed and their validity is tested to determine the normal of Venusian bow shocks. It is found that MVA method is the better than magnetic coplanarity, and 95% shock crossings can be accurately determined by the method. However, the occurrence of the shock normal which is not determined accurately by magnetic coplanarity increases with the decrease of the solar zenith angle (SZA). At the same time, compared with quasi-parallel shocks, there is more occurrence of the shock normal which cannot be determined accurately by magnetic coplanarity for quasi-perpendicular shocks. 展开更多
关键词 共面性 MVA 金星 激波 定正 太阳天顶角 测量方法 方差分析
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法向磁场作用下槽道流内的精确相干态 被引量:1
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作者 董帅 史晓梦 +3 位作者 王乐冰 李森 李顺治 吴正人 《力学学报》 EI CAS CSCD 北大核心 2023年第8期1618-1626,共9页
层流-湍流转捩过程一直以来都是流体力学的研究热点,精确相干态对于预测转捩路径和理解湍流自维持动力循环过程具有重要的意义.为了研究法向磁场对槽道流转捩过程的影响,文章利用直接数值模拟方法结合二分法,在槽道泊肃叶流中寻找不同... 层流-湍流转捩过程一直以来都是流体力学的研究热点,精确相干态对于预测转捩路径和理解湍流自维持动力循环过程具有重要的意义.为了研究法向磁场对槽道流转捩过程的影响,文章利用直接数值模拟方法结合二分法,在槽道泊肃叶流中寻找不同雷诺数和哈特曼数组合下的精确相干态-周期轨道解,并对施加磁场前后精确相干态的结构与形态进行了对比分析.结果发现,在本文考虑的参数组合下,精确相干结构在施加磁场前后并无明显变化,均由位于通道中心的流向条带及其两侧的流向漩涡构成.随雷诺数的增大,精确相干态的轨道周期变长,而扰动能振幅则减小.当磁场强度增大时,流场内各方向上的扰动能呈周期性振荡变化,且流场内的相干结构向两侧的壁面迁移,扰动速度振幅增大.无磁场作用时,精确相干态的扰动能正比于Re^(-2.36),且不同Re数下的均方根扰动速度分布具有相似性.施加法向磁场后,上述标度律不变,均方根速度分布不再具有相似性,精确相干态的扰动能随磁场强度增加而增大,表明磁场对扰动具有一定的抑制作用,从而使流场保持相对的稳定. 展开更多
关键词 精确相干态 法向磁场 槽道流 二分法 转捩
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焊接残余应力调控技术的研究与应用进展 被引量:5
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作者 郭政伟 龙伟民 +2 位作者 王博 祁婷 李宁波 《材料导报》 EI CAS CSCD 北大核心 2023年第2期144-150,共7页
残余应力在焊接构件中普遍存在,不均衡分布的残余应力是构件变形和开裂的根源,直接影响焊接构件的承载能力、稳定性和服役寿命。焊接残余应力随构件服役环境及外界载荷变化而动态分布,对残余应力的消减、均化应贯穿焊接构件设计、生产... 残余应力在焊接构件中普遍存在,不均衡分布的残余应力是构件变形和开裂的根源,直接影响焊接构件的承载能力、稳定性和服役寿命。焊接残余应力随构件服役环境及外界载荷变化而动态分布,对残余应力的消减、均化应贯穿焊接构件设计、生产和服役全生命周期。焊接变形及残余应力控制关键在于塑性区的调控,合理的焊接顺序能有效降低工件应力集中并改善其分布状态,及时的焊前预热及焊后回火能有效降低接头温度梯度、松弛应力集中、消减残余应力。对焊缝的锤击松弛处理能抵消部分焊缝区收缩,减小残余拉应力。对焊缝及周边区域施加拉伸、振动时效、超声冲击和喷丸强化等力学形变载荷,可与焊件内部应力叠加促进塑性形变,释放、均衡残余应力。这些方法各有优势,但均需密切结合构件材料、结构及性能控制要求来进行选择。随着制造业转型发展及绿色环保政策驱动,未来工程装备残余应力调控技术会向绿色环保、柔性高效、过程可控、专业化方向转变。 展开更多
关键词 焊接残余应力 焊接顺序 热时效 超声冲击 脉冲磁场
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基于MSE/PVDF复合结构转速传感器的研究
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作者 居本祥 周光银 吕冰 《仪表技术与传感器》 CSCD 北大核心 2023年第11期17-22,28,共7页
磁敏弹性体(MSE)是一种具有优良磁响应特性的磁敏材料,在磁场作用下将产生垂直其表面的磁致法向力,结合聚偏氟乙烯(PVDF)的正压电效应,针对转速检测提出一种结合两者特性的转速传感器,在敏感单元中设计由MSE与PVDF压电单元组成复合结构... 磁敏弹性体(MSE)是一种具有优良磁响应特性的磁敏材料,在磁场作用下将产生垂直其表面的磁致法向力,结合聚偏氟乙烯(PVDF)的正压电效应,针对转速检测提出一种结合两者特性的转速传感器,在敏感单元中设计由MSE与PVDF压电单元组成复合结构,通过复合结构感知磁场激励以实现转速检测,并从微观与宏观层面分析了检测机理,采用自建测试系统确立了磁致法向力与磁场间的关系,PVDF的动态形变响应及传感器的输出特性。结果表明:以复合结构为核心的敏感单元对测试转速的磁场激励表现出稳定的电压峰值响应,并能够实现对中高转速的准确检测。 展开更多
关键词 磁敏弹性体 复合结构 转速传感器 磁致法向力 正压电效应
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航空磁测中正常地磁场校正 被引量:6
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作者 骆遥 罗锋 +2 位作者 王明 何辉 王林飞 《物探化探计算技术》 CAS CSCD 2015年第5期552-559,共8页
在地球物理勘探中,磁异常是地磁场同正常地磁场的差,去除正常地磁场背景能够获得磁异常信息,正常地磁场校正是航空磁测资料处理中的必要环节。这里从航空磁测资料处理实际出发,针对正常地磁场计算、校正中坐标系变换、改正方式等关键问... 在地球物理勘探中,磁异常是地磁场同正常地磁场的差,去除正常地磁场背景能够获得磁异常信息,正常地磁场校正是航空磁测资料处理中的必要环节。这里从航空磁测资料处理实际出发,针对正常地磁场计算、校正中坐标系变换、改正方式等关键问题进行分析,同时对行业规范中存在的问题进行讨论,以明确航空磁测中正常地磁场校正处理的方式,这些结论可供地面磁法勘探参考。 展开更多
关键词 正常地磁场 国际地磁参考场 航空磁测 航磁资料处理 磁法勘探
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高速储能飞轮用无铁心永磁无刷直流电动机的分析与设计 被引量:28
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作者 徐衍亮 赵建辉 房建成 《电工技术学报》 EI CSCD 北大核心 2004年第12期24-28,共5页
采用电磁场的数值计算方法,对比分析了常规磁体结构和HALBACH磁体结构的外转子无定子铁心永磁无刷直流电机,重点分析了磁体厚度变化对两种磁体结构电机气隙磁通密度、磁通及转子轭部磁通的影响,认为HALBACH磁体结构特别适于外转子高速... 采用电磁场的数值计算方法,对比分析了常规磁体结构和HALBACH磁体结构的外转子无定子铁心永磁无刷直流电机,重点分析了磁体厚度变化对两种磁体结构电机气隙磁通密度、磁通及转子轭部磁通的影响,认为HALBACH磁体结构特别适于外转子高速飞轮用无铁心电机。提出HALBACH磁体结构电机的场路结合设计计算方法,并通过一25Nms角动量(30000r/min额定转速)的高速外转子飞轮用无铁心永磁无刷直流电动机进行了试验验证。 展开更多
关键词 飞轮系统 永磁无刷直流电动机 HALBACH磁体 常规磁体 场路结合设计
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永磁直线同步电机推力波动约束 被引量:20
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作者 陆华才 江明 +1 位作者 郭兴众 陈其工 《电工技术学报》 EI CSCD 北大核心 2012年第3期128-132,共5页
由齿槽力、边端力及法向吸力引起的推力波动是影响永磁直线同步电机(PMLSM)动态性能的主要因素。为了实现高速精密直接驱动系统,通过对PMLSM进行有限元分析建模,分析了齿槽力变化规律,利用傅里叶级数拟合得到齿槽力变化曲线;设计了齿槽... 由齿槽力、边端力及法向吸力引起的推力波动是影响永磁直线同步电机(PMLSM)动态性能的主要因素。为了实现高速精密直接驱动系统,通过对PMLSM进行有限元分析建模,分析了齿槽力变化规律,利用傅里叶级数拟合得到齿槽力变化曲线;设计了齿槽力电流预测控制模型,对齿槽力引起的推力波动进行补偿;同时设计了扰动观测器对其他因素引起的推力波动进行补偿,进一步削弱了推力波动。最后,通过实验验证PMLSM推力波动补偿控制系统的有效性,补偿后电流和速度的波动都得到了很大改善,能够实现较高精度的直接驱动系统。 展开更多
关键词 永磁直线同步电机 齿槽力 法向力 磁场定向控制
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各向异性标准化方差计算重磁源边界 被引量:14
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作者 张恒磊 刘天佑 杨宇山 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2011年第7期1921-1927,共7页
在重磁源边界定位方法中,传统的梯度方法易受干扰的影响使计算的边界混乱,而且在弱异常处由于叠加异常的影响很难识别场源边界.本文首先利用坐标旋转构造了各向异性高斯函数,提出了各向异性标准化方差计算重磁源边界的方法.理论分析与... 在重磁源边界定位方法中,传统的梯度方法易受干扰的影响使计算的边界混乱,而且在弱异常处由于叠加异常的影响很难识别场源边界.本文首先利用坐标旋转构造了各向异性高斯函数,提出了各向异性标准化方差计算重磁源边界的方法.理论分析与模型实验详细阐明了该方法的数学含义,并通过干扰分析验证了方法的稳定性与有效性,结合中扬子地区航磁异常处理实例,表明通过计算各向异性标准化方差,可以有效地确定重磁源边界,尤其对微弱异常能够实现较好的边界定位,计算的边界分辨率高且信息丰富,有利于资料的综合解释. 展开更多
关键词 位场勘探 各向异性标准化方差 梯度算法 重磁源边界
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