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Influence of different magnetic forces on the effect of colonic anastomosis in rats
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作者 Bo-Yan Tian Miao-Miao Zhang +2 位作者 Jia Ma Yi Lyu Xiao-Peng Yan 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第3期860-870,共11页
BACKGROUND Despite much work having been conducted on magnetic compression anastomo-sis(MCA)in the digestive tract,there are no reports on the influence of magnetic force on the anastomosis.AIM To investigate the effe... BACKGROUND Despite much work having been conducted on magnetic compression anastomo-sis(MCA)in the digestive tract,there are no reports on the influence of magnetic force on the anastomosis.AIM To investigate the effect of different magnetic force magnets on the MCA of the digestive tract.METHODS Two groups of magnets of the same sizes but different magnetic forces were designed and produced.A total of 24 Sprague-Dawley rats were randomly assigned into two groups(powerful magnet group and common magnet group),with 12 rats in each group.Two types of magnets were used to complete the colonic side-to-side anastomosis of the rats.The operation time and magnet discharge time were recorded.The anastomotic specimens were obtained 4 wk after the operation and then the burst pressure and diameter of the anastomosis were measured,and the anastomosis was observed via the naked eye and subjected to histological examination.RESULTS The magnetic forces of the powerful and common magnet groups at zero distance were 8.26 N and 4.10 N,respectively.The colonic side-to-side anastomosis was completed in all 24 rats,and the operation success rate and postoperative survival rate were 100%.No significant difference was noted in the operation time between the two groups.The magnet discharge time of the powerful magnet group was slightly longer than that of the common magnet group,but the difference was not statistically significant(P=0.513).Furthermore,there was no statistical difference in the burst pressure(P=0.266)or diameter of magnetic anastomosis(P=0.095)between the two groups.The gross specimens of the two groups showed good anastomotic healing,and histological observation indicated good mucosal continuity without differences on healing.CONCLUSION In the rat colonic side-to-side MCA model,both the powerful magnet with 8.26 N and the common magnet with 4.10 N showed no significant impact on the anastomosis establishment process or its effect. 展开更多
关键词 magnetosurgery magnetic compression anastomosis Colonic anastomosis magnetic force RATS
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Harmonics in the Squirrel Cage Induction Motor,Analytic Calculation Part Ⅱ:Synchronous Parasitic Torques,Radial Magnetic Forces 被引量:1
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作者 G.Kovács 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第4期404-421,共18页
The magnetic field generated in the air gap of the cage asynchronous machine and the harmonics of the magnetomotive forces creating that magnetic field,as well as the synchronous parasitic torques,radial magnetic forc... The magnetic field generated in the air gap of the cage asynchronous machine and the harmonics of the magnetomotive forces creating that magnetic field,as well as the synchronous parasitic torques,radial magnetic forces have been discussed in great detail in the literature,but always separately,for a long time.However,systematization of the phenomenon still awaits.Therefore,it is worth summarizing the completeness of the phenomena in a single study–with a new approach at the same time-in order to reveal the relationships between them.The role of rotor slot number is emphasized much more than before.New formulas derived for both synchronous torques and radial magnetic forces are used for further investigation.It will be shown that both phenomena in subject must be treated together.Formulas will be provided to take into account attenuation.Design guide will be provided to avoid dangerous rotor slot numbers.It will be shown that the generation of synchronous torques and radial magnetic forces do not depend–in this new approach-on the slot combination,but on the rotor slot number itself. 展开更多
关键词 Squirrel cage induction motor Synchronous parasitic torques Radial magnetic forces Winding harmonics
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Magnetic domain structures in ultrathin Bi_(2)Te_(3)/CrTe_(2) heterostructures
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作者 夏体瑞 杨笑天 +6 位作者 张逸凡 刘馨琪 蔡新雨 刘畅 姚岐 寇煦丰 王文波 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期511-517,共7页
Chromium tellurium compounds are important two-dimensional van der Waals ferromagnetic materials with high Curie temperature and chemical stability in air,which is promising for applications in spintronic devices.Here... Chromium tellurium compounds are important two-dimensional van der Waals ferromagnetic materials with high Curie temperature and chemical stability in air,which is promising for applications in spintronic devices.Here,highquality spin-orbital-torque(SOT)device,Bi_(2)Te_(3)/CrTe_(2)heterostructure was epitaxially grown on Al_(2)O_(3)(0001)substrates.Anomalous Hall measurements indicate the existence of strong ferromagnetism in this device with the CrTe_(2)thickness down to 10 nm.In order to investigate its micromagnetic structure,cryogenic magnetic force microscope(MFM)was utilized to measure the magnetic domain evolutions at various temperatures and magnetic fields.The virgin domain state of the device shows a worm-like magnetic domain structure with the size around 0.6μm-0.8μm.Larger irregular-shape magnetic domains(>1μm)can be induced and pinned,after the field is increased to coercive field and ramped back to low fields.The temperature-dependent MFM signals exhibit a nice mean-field-like ferromagnetic transition with Curie temperature around 201.5 K,indicating a robust ferromagnetic ordering.Such a device can be potentially implemented in future magnetic memory technology. 展开更多
关键词 CrTe_(2) magnetic domain magnetic force microscopy
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Ion and electron motions in the outer electron diffusion region of collisionless magnetic reconnection
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作者 Cong Chang QuanMing Lu +2 位作者 San Lu Kai Huang RongSheng Wang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期472-478,共7页
Two-dimensional particle-in-cell simulations are performed to study the coupling between ion and electron motions in collisionless magnetic reconnection.The electron diffusion region(EDR),where the electron motions ar... Two-dimensional particle-in-cell simulations are performed to study the coupling between ion and electron motions in collisionless magnetic reconnection.The electron diffusion region(EDR),where the electron motions are demagnetized,is found to have a two-layer structure:an inner EDR near the reconnection site and an outer EDR that is elongated to nearly 10 ion inertial lengths in the outflow direction.In the inner EDR,the speed of the electron outflow increases when the electrons move away from the X line.In the outer EDR,the speed of the electron outflow first increases and then decreases until the electrons reach the boundary of the outer EDR.In the boundary of the outer EDR,the magnetic field piles up and forms a depolarization front.From the perspective of the fluid,a force analysis on the formation of electron and ion outflows has also been investigated.Around the X line,the electrons are accelerated by the reconnection electric field in the out-of-plane direction.When the electrons move away from the X line,we find that the Lorentz force converts the direction of the accelerated electrons to the x direction,forming an electron outflow.Both electric field forces and electron gradient forces tend to drag the electron outflow.Ion acceleration along the x direction is caused by the Lorentz force,whereas the pressure gradient force tends to decelerate the ion outflow.Although these two terms are important,their effects on ions are almost offset.The Hall electric field force does positive work on ions and is not negligible.The ions are continuously accelerated,and the ion and electron outflow velocities are almost the same near the depolarization front. 展开更多
关键词 collisionless magnetic reconnection electron diffusion region force analysis particle-in-cell simulation
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The Pairing Analysis Improvement of Magnetized Structure in Electromagnetic Bulging Process in Case of Tube with Field Shaper
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作者 Blaise Kevine Lenz Soronga Zhanqian Zhan +6 位作者 Jing Liu Jonas Asamoah Mohamed Bangali Bangura Matala Makiese N’kodia Kambani Chrionie Md Jobayer Hossain Yongdong Chen 《Journal of Electromagnetic Analysis and Applications》 2024年第4期43-67,共25页
In the current practical science, the accuracy in the formability of metal alloys being the goal when using electromagnetic forming (EMF) technology, which is a high-speed processing technology that uses Lorentz force... In the current practical science, the accuracy in the formability of metal alloys being the goal when using electromagnetic forming (EMF) technology, which is a high-speed processing technology that uses Lorentz forces to achieve plastic deformation of sheet metal;according to the previous analysis, the results have shown that in most cases, the Lorentz force acting on the workpiece (metal) is not uniform, there are uneven axial deformations of the metal plates which prevent the rapid advancement of today’s technology. In this article, we presented some advanced analyzes which will lead us to improve the technical solution for the problems of non-uniform axial deformations of the metals in the traditional tube electromagnetic forming technology (EMF). A field shaper is used as a practical forming tool to influence the magnetic field and magnetic pressure distribution, thereby improving the forming ability and result during the electromagnetic forming (EMF) process and we see that induced eddy current control is realized by changing the structural parameters of the magnetic field shaper;which improves the strength and controllability of the magnetic force that acts on the workpiece;thereby a greater radial magnetic pressure can be achieved with field shaper than the case without it;the field shaper regulates the electromagnetic force, the distribution of the magnetic pressure decreases, and the uniform force area of the tube increases which effectively enhances the uniform range of the pipe electromagnetic bulging and the electromagnetic induction coupling between the coil and the metallic workpiece is generally required to produce the Lorentz forces. Using COMSOL Multiphysics® simulation software helped us to accurately represent the real world, simulating multiple physical effects that happened in this model during the process. 展开更多
关键词 Electromagnetic Forming Field Shaper Lorentz force magnetic Pressure Distribution
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Dynamic Analysis of Axial Magnetic Forces for DVD Spindle Motors 被引量:1
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作者 Chung-Ping Liu (Department of Electrical Engineering, Yuan Ze University, Chungli 320, Taiwan-China) Yeong-Hwa Chang and Tsung-Kun Lin (Department of Electrical Engineering, Chung Cheng Institute of Technology, Taoyuan 335, Taiwan-China) Der-Ray Huang, T 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期246-247,共2页
The axial magnetic force, induced by the complicated flux linkage distribution from rotor magnet and stator slotted, is constructed by different relative heights and calculated by 3D finite element method (FEM) to ana... The axial magnetic force, induced by the complicated flux linkage distribution from rotor magnet and stator slotted, is constructed by different relative heights and calculated by 3D finite element method (FEM) to analyze the dynamic characteristics for a DVD spindle motor. The axial magnetic force is designed to provide an axial stiffness, and govern the natural frequency of the dynamic performance. According to the simulation results and experimental measurements, the dynamic behaviors are significantly improved with a variation of relative height of rotor magnet and stator slotted on a DVD spindle motor. 展开更多
关键词 DVD Dynamic Analysis of Axial magnetic forces for DVD Spindle Motors
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Fast Calculation of Electromagnetic Forces in IPMSMs Under PWM VSI Supply Based on Small-Signal Time-Harmonic Finite Element Method 被引量:3
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作者 Sa Zhu Jianbo Lu Feng Zeng 《CES Transactions on Electrical Machines and Systems》 CSCD 2022年第1期67-76,共10页
This paper introduces a novel method for fast calculating the electromagnetic forces in interior permanent magnet synchronous machines(IPMSMs)under pulse width modulation(PWM)voltage source inverter(VSI)supply based o... This paper introduces a novel method for fast calculating the electromagnetic forces in interior permanent magnet synchronous machines(IPMSMs)under pulse width modulation(PWM)voltage source inverter(VSI)supply based on the small-signal time-harmonic finite element analysis(THFEA),which has been successfully utilized for fast calculating the PWMinduced losses in silicon steel sheets and permanent magnets.Based on the small-signal THFEA,the functional relationships between high-frequency harmonic voltages(HFHVs)and corresponding airgap flux densities are established,which are used for calculating the flux density spectra caused by each HFHV in the PWM voltage spectra.Then,the superposition principle is applied for calculating the flux density spectra caused by fundamental currents and all HFHVs,which are converted to the electromagnetic force spectra at last.The relative errors between the force density spectra calculated with the proposed method and those obtained from traditional time-stepping finite element analysis(TSFEA)using PWM voltages as input are within 3.1%,while the proposed method is 24 times faster than the traditional TSFEA. 展开更多
关键词 Time-harmonic finite element analysis(THFEA) Interior permanent magnet synchronous machines(IPMSMs) Electromagnetic forces Pulse width modulation Vibration and acoustic noise
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Interaction forces between soft magnetic particles in uniform and non-uniform magnetic fields
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作者 Ayyoub Mehdizadeh James F.Klausner Nima Rahmatian 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第6期921-929,共9页
The influence of the magnetization of a soft magnetic sphere on the surrounding magnetic field is measured and characterized.The interaction force between two soft magnetic particles is directly measured using an ultr... The influence of the magnetization of a soft magnetic sphere on the surrounding magnetic field is measured and characterized.The interaction force between two soft magnetic particles is directly measured using an ultra precision load sensor in uniform and non-uniform magnetic fields. The interaction force largely follows an inverse fourth power law as a function of separation distance between particle centers. At small distances,the effect of magnetization of one particle on the magnetization of its adjacent particle causes the attractive(repulsive) force to be larger(smaller) than that predicted by the inverse fourth power law.The theoretical prediction based on a modified dipole model,that takes into account the coupling effect of the magnetization among soft magnetic particles,gives excellent agreement with the measured force in a uniform magnetic field.The interaction force under a non-uniform applied magnetic field can be reasonably predicted using the dipole-dipole interaction model when the local magnetic field is used to determine the magnetization. 展开更多
关键词 magnetic force magnetic charge model magnetic dipole model Soft magnetic particle
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Probing the magnetization switching with in-plane magnetic anisotropy through field-modified magnetoresistance measurement
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作者 Runrun Hao Kun Zhang +4 位作者 Yinggang Li Qiang Cao Xueying Zhang Dapeng Zhu Weisheng Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期101-106,共6页
Effective probing current-induced magnetization switching is highly required in the study of emerging spin-orbit torque(SOT)effect.However,the measurement of in-plane magnetization switching typically relies on the gi... Effective probing current-induced magnetization switching is highly required in the study of emerging spin-orbit torque(SOT)effect.However,the measurement of in-plane magnetization switching typically relies on the giant/tunneling magnetoresistance measurement in a spin valve structure calling for complicated fabrication process,or the non-electric approach of Kerr imaging technique.Here,we present a reliable and convenient method to electrically probe the SOT-induced in-plane magnetization switching in a simple Hall bar device through analyzing the MR signal modified by a magnetic field.In this case,the symmetry of MR is broken,resulting in a resistance difference for opposite magnetization orientations.Moreover,the feasibility of our method is widely evidenced in heavy metal/ferromagnet(Pt/Ni_(20)Fe_(80) and W/Co_(20)Fe_(60)B_(20))and the topological insulator/ferromagnet(Bi_(2)Se_(3)/Ni_(20)Fe_(80)).Our work simplifies the characterization process of the in-plane magnetization switching,which can promote the development of SOT-based devices. 展开更多
关键词 magnetORESISTANCE in-plane magnetization switching electrical detection
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Behavior of fractional quantum Hall states in LLL and 1LL with in-plane magnetic field and Landau level mixing:A numerical investigation
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作者 Lin-Peng Yang Qi Li Zi-Xiang Hu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期492-497,共6页
By exactly solving the effective two-body interaction for a two-dimensional electron system with layer thickness and an in-plane magnetic field, we recently found that the effective interaction can be described by the... By exactly solving the effective two-body interaction for a two-dimensional electron system with layer thickness and an in-plane magnetic field, we recently found that the effective interaction can be described by the generalized pseudopoten- tials (PPs) without the rotational symmetry. With this pseudopotential description, we numerically investigate the behavior of the fractional quantum Hall (FQH) states both in the lowest Landau level (LLL) and first excited Landau level (1LL). The enhancements of the 7/3 FQH state on the 1LL for a small tilted magnetic field are observed when layer thickness is larger than some critical values, while the gap of the 1/3 state in the LLL monotonically reduced with increasing the in-plane field. From the static structure factor calculation, we find that the systems are strongly anisotropic and finally enter into a stripe phase with a large tilting. With considering the Landau level mixing correction on the two-body interaction, we find the strong LL mixing cancels the enhancements of the FQH states in the 1LL. 展开更多
关键词 fractional quantum Hall in-plane magnetic field PSEUDOPOTENTIALS Landau level mixing
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Phase diagram and collective modes in Rashba spin–orbit coupled BEC: Effect of in-plane magnetic field
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作者 董冬 邹旭波 郭光灿 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期387-391,共5页
We studied the system of pure Rashba spin–orbit coupled Bose gas with an in-plane magnetic field. Based on the mean field theory, we obtained the zero temperature phase diagram of the system which exhibits three phas... We studied the system of pure Rashba spin–orbit coupled Bose gas with an in-plane magnetic field. Based on the mean field theory, we obtained the zero temperature phase diagram of the system which exhibits three phases, plane wave(PW) phase, striped wave(SW) phase, and zero momentum(ZM) phase. It was shown that with a growing in-plane field,both SW and ZM phases will eventually turn into the PW phase. Furthermore, we adopted the Bogoliubov theory to study the excitation spectrum as well as the sound speed. 展开更多
关键词 Rashba spin–orbit coupling excitation spectrum in-plane magnetic field
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THE COMPUTATION OF MAGNETIC FORCES OF NEW TYPE HARD MAGNETIC MATERIALS AND THE STUDY ON THE TEST SYSTEM FOR THE MECHANICAL PARAMETERS
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作者 孙景 穆宗学 +1 位作者 张安欣 孙铁麟 《Transactions of Tianjin University》 EI CAS 1996年第2期45+42-44,共4页
This paper presents theoretical computations of magnetic force bearings made of new type hard magnetic materials neodymium iron boron. A set of devices capable of simultaneously measuring magnetic eccentricity, ... This paper presents theoretical computations of magnetic force bearings made of new type hard magnetic materials neodymium iron boron. A set of devices capable of simultaneously measuring magnetic eccentricity, crosswise stiffness and magnetic pulling force is designed. 展开更多
关键词 hard magnetic material magnetic force test system
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Finite Element Based Analysis of Magnetic Forces between Planar Spiral Coils
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作者 Abbas Shiri Davoud E. Moghadam +1 位作者 Mohammad R. A. Pahlavani Abbas Shoulaie 《Journal of Electromagnetic Analysis and Applications》 2010年第5期311-317,共7页
This paper elaborates on the magnetic forces between current carrying planar spiral coils. Direct and concentric rings methods are employed in order to calculate the magnetic force between these coils. The results obt... This paper elaborates on the magnetic forces between current carrying planar spiral coils. Direct and concentric rings methods are employed in order to calculate the magnetic force between these coils. The results obtained by two calculation methods show the efficiency of the replaced rings method in both simplicity and calculation time. Simula-tions using the Finite Element Method (FEM) are carried out to analyze the distribution of the magnetic flux density around the coils. Also, coils with precise size have been constructed and tested. The experimental results as well as the results obtained by FEM are used to validate the accuracy of the calculations. 展开更多
关键词 magnetic force Finite Element METHOD CONCENTRIC RINGS METHOD PLANAR SPIRAL Coils
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Shape Anisotropy and Resonance Mode Guided Reliable Interconnect Design for In-plane Magnetic Logic
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作者 Xiao-Kuo Yang Bin Zhang +4 位作者 Jia-Hao Liu Ming-Liang Zhang Wei-Wei Li Huan-Qing Cui Bo Wei 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期129-132,共4页
Dipole coupled nanomagnets controlled by the static Zeeman field can form various magnetic logic interconnects.However, the corner wire interconnect is often unreliable and error-prone at room temperature. In this stu... Dipole coupled nanomagnets controlled by the static Zeeman field can form various magnetic logic interconnects.However, the corner wire interconnect is often unreliable and error-prone at room temperature. In this study, we address this problem by making it into a reliable type with trapezoid-shaped nanomagnets, the shape anisotropy of which helps to offer the robustness. The building method of the proposed corner wire interconnect is discussed,and both its static and dynamic magnetization properties are investigated. Static micromagnetic simulation demonstrates that it can work correctly and reliably. Dynamic response results are reached by imposing an ac microwave field on the proposed corner wire. It is found that strong ferromagnetic resonance absorption appears at a low frequency. With the help of a very small ac field with the peak resonance frequency, the required static Zeeman field to switch the corner wire is significantly decreased by ~21 m T. This novel interconnect would pave the way for the realization of reliable and low power nanomagnetic logic circuits. 展开更多
关键词 net In Shape Anisotropy and Resonance Mode Guided Reliable Interconnect Design for in-plane magnetic Logic
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Magnetic force distribution and deformation law of sheet using uniform pressure electromagnetic actuator 被引量:1
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作者 崔晓辉 莫健华 +1 位作者 肖师杰 杜二虎 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2484-2489,共6页
The distribution of magnetic forces and current on sheet and coil was analyzed in detail according to the structural parameter of the coil which was invalid.The result shows that the current direction based on simulat... The distribution of magnetic forces and current on sheet and coil was analyzed in detail according to the structural parameter of the coil which was invalid.The result shows that the current direction based on simulation result agrees with the principles of uniform pressure electromagnetic actuator.The reason for coil failure was proposed.Then the magnetic forces on the sheet were input into an explicit finite element software ANSYS/LS-DYNA to analyze the deformation law of the sheet. 展开更多
关键词 electromagnetic sheet forming magnetic force uniform pressure electromagnetic actuator numerical method
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Vibration analysis of maglev three-span rigid frame bridge considering magnetic force
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作者 滕延锋 滕念管 寇新建 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期571-576,共6页
The dynamic interaction between the maglev vehicle and the three-span rigid frame bridge is discussed. With the consideration of magnetic force, the interaction model is developed. Numerical simulations are performed ... The dynamic interaction between the maglev vehicle and the three-span rigid frame bridge is discussed. With the consideration of magnetic force, the interaction model is developed. Numerical simulations are performed to study the dynamic characteristics of the bridge during vehicle movement along the bridge. The results show that a reasonable value of the linear stiffness ratio of columns to beams is between 2. 0 and 3.0. The dynamic responses of the bridge are aggravated with the decrease in bending rigidity and the increase in vehicle speed and the span ratio of the bridge. It is suggested that a definite way is to control impact coefficients and acceleration in the dynamic design of the bridge. It is unsuitable to adopt the moving load model and the moving mass model in the design. The proposed results can serve in the design of high-speed maglev three-span rigid frame bridges. 展开更多
关键词 maglev transportation system three-span rigid frame bridge vertical vibration magnetic force control system
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Effect of electromagnetic force on melt induced by traveling magnetic field 被引量:5
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作者 苏彦庆 徐严谨 +2 位作者 赵雷 郭景杰 傅恒志 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第4期662-667,共6页
A new apparatus was designed to measure the electromagnetic force and a computational study of the traveling magnetic field(TMF)and its application to the Ga-In-Sn melt(with low melting point),then the forces on Al,Mg... A new apparatus was designed to measure the electromagnetic force and a computational study of the traveling magnetic field(TMF)and its application to the Ga-In-Sn melt(with low melting point),then the forces on Al,Mg,and Li melt,were simulated. The result show that the electromagnetic force on the melt increases linearly with the increasing length of the melt in the TMF.The TMF-induced Lorentz force increases with increasing frequency,and then decreases.The maximum value is obtained when the current frequency is 160 Hz,over that frequency the force decreases rapidly.When the iron-core is activated,the force increases when the melt closes to the iron-core.The Lorentz forces have inversely-proportional relationships with the electrical resistivity,the dfx/dρdecreases and the dfy/dρincreases with the increasing electrical resistivity(df/dρis the slope of the Lorentz force profile). 展开更多
关键词 electromagnetic force traveling magnetic field Ga-In-Sn melt molten metal
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In-plane forced vibration of curved pipe conveying fluid by Green function method 被引量:7
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作者 Qianli ZHAO Zhili SUN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第10期1397-1414,共18页
The Green function method (GFM) is utilized to analyze the in-plane forced vibration of curved pipe conveying fluid, where the randomicity and distribution of the external excitation and the added mass and damping r... The Green function method (GFM) is utilized to analyze the in-plane forced vibration of curved pipe conveying fluid, where the randomicity and distribution of the external excitation and the added mass and damping ratio are considered. The Laplace transform is used, and the Green functions with various boundary conditions are obtained subsequently. Numerical calculations are performed to validate the present solutions, and the effects of some key parameters on both tangential and radial displacements are further investigated. The forced vibration problems with linear and nonlinear motion constraints are also discussed briefly. The method can be radiated to study other forms of forced vibration problems related with pipes or more extensive issues. 展开更多
关键词 in-plane forced vibration curved pipe conveying fluid Green functionmethod (GFM) motion constraint
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Magnetic Microstructures of 2∶17 Type Sm(Co,Fe,Cu,Zr)_z Magnets Detected by Magnetic Force Microscopy 被引量:3
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作者 夏爱林 郭朝晖 +1 位作者 李卫 韩宝善 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第2期214-217,共4页
The magnetic microstructures of 2:17 type Sm (Co, Fe, Cu, Zr)z magnets were detected by magnetic force microscopy. Comparing the microstructures of the specimens eoated with and without Ta thin film before and afte... The magnetic microstructures of 2:17 type Sm (Co, Fe, Cu, Zr)z magnets were detected by magnetic force microscopy. Comparing the microstructures of the specimens eoated with and without Ta thin film before and after heat-treatment, it is found that: (a) as a protection layer, Ta coating layer about 20 nm thick can effectively restrain Sm volatilization under high temperature; (b) the stress built in the 2.17 type Sm-Co magnets during specimen preparation only affects some local parts of the domain structures; (c) the magnetic microstructures vary largely for specimens heat-treated at high temperature without Ta film coating due to Sm volatilization. In addition, by comparing with high coercivity Fe-Pt point tips, it is found that the Co-Cr thin-film tips are not suitable for detecting the magnetic microstructures of strong permanent magnets. 展开更多
关键词 2:17 type Sm-Co permanent magnets magnetic microstructures magnetic force microscopy (MFM) rare earths
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Rectification of magnetic force tracker using neural network inaugmented reality system 被引量:2
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作者 丰艳 陈一民 《Journal of Shanghai University(English Edition)》 CAS 2006年第5期431-435,共5页
Nonlinear errors always exist in data obtained from tracker in augmented reality (AR), which badly influence the effect of AR. This paper proposes to rectify the errors using BP neural network. As BP neural network ... Nonlinear errors always exist in data obtained from tracker in augmented reality (AR), which badly influence the effect of AR. This paper proposes to rectify the errors using BP neural network. As BP neural network is prone to getting into local extrema and convergence is slow, genetic algorithm is employed to optimize the initial weights and threshold of neural network. This paper discusses how to set the crucial parameters in the algorithm. Experimental results show that the method ensures that the neural network achieves global convergence quickly and correctly. Tracking precision of AR system is improved after the tracker is rectified, and the third dimension of AR system is enhanced. 展开更多
关键词 BP neural network genetic algorithm augmented reality(AR) magnetic force tracker rectification.
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