期刊文献+
共找到2,580篇文章
< 1 2 129 >
每页显示 20 50 100
Application of shifted lattice model to 3D compressible lattice Boltzmann method
1
作者 黄好雨 金科 +1 位作者 李凯 郑晓静 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期312-320,共9页
An additional potential energy distribution function is introduced on the basis of previous D3Q25 model,and the equilibrium distribution function of D3Q25 is obtained by spherical function.A novel three-dimensional(3D... An additional potential energy distribution function is introduced on the basis of previous D3Q25 model,and the equilibrium distribution function of D3Q25 is obtained by spherical function.A novel three-dimensional(3D)shifted lattice model is proposed,therefore a shifted lattice model is introduced into D3Q25.Under the finite volume scheme,several typical compressible calculation examples are used to verify whether the numerical stability of the D3Q25 model can be improved by adding the shifted lattice model.The simulation results show that the numerical stability is indeed improved after adding the shifted lattice model. 展开更多
关键词 lattice Boltzmann method shifted lattice model compressible flow finite volume method
下载PDF
Numerical Solutions of Fractional Variable Order Differential Equations via Using Shifted Legendre Polynomials
2
作者 Kamal Shah Hafsa Naz +2 位作者 Thabet Abdeljawad Aziz Khan Manar A.Alqudah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期941-955,共15页
In this manuscript,an algorithm for the computation of numerical solutions to some variable order fractional differential equations(FDEs)subject to the boundary and initial conditions is developed.We use shifted Legen... In this manuscript,an algorithm for the computation of numerical solutions to some variable order fractional differential equations(FDEs)subject to the boundary and initial conditions is developed.We use shifted Legendre polynomials for the required numerical algorithm to develop some operational matrices.Further,operational matrices are constructed using variable order differentiation and integration.We are finding the operationalmatrices of variable order differentiation and integration by omitting the discretization of data.With the help of aforesaid matrices,considered FDEs are converted to algebraic equations of Sylvester type.Finally,the algebraic equations we get are solved with the help of mathematical software like Matlab or Mathematica to compute numerical solutions.Some examples are given to check the proposed method’s accuracy and graphical representations.Exact and numerical solutions are also compared in the paper for some examples.The efficiency of the method can be enhanced further by increasing the scale level. 展开更多
关键词 Operational matrices shifted legendre polynomials FDEs variable order
下载PDF
基于The Shifted User的图书馆个性信息推送服务模式研究 被引量:8
3
作者 杨九龙 《情报杂志》 CSSCI 北大核心 2008年第12期139-141,共3页
评析现行主流个性信息推送服务模式,发现尚不能有效解决同一图书馆用户的多层次信息需求。文中提出基于The shifted user(可变用户)的个性信息推送服务模式则允许用户可拥有个人和专业双重身份以获取相应的资源和服务,满足用户的特定层... 评析现行主流个性信息推送服务模式,发现尚不能有效解决同一图书馆用户的多层次信息需求。文中提出基于The shifted user(可变用户)的个性信息推送服务模式则允许用户可拥有个人和专业双重身份以获取相应的资源和服务,满足用户的特定层次需求。模式由用户身份注册、建立用户需求档案、专业数据中心、资源组织与处理、资源推送、资源更新、追踪和评价服务等部分组成。 展开更多
关键词 信息服务 个性化推送 The shifted USER
下载PDF
Effect Due to the Particle Nature of the Doppler Shifted Radiation on the Dynamics of the Spherical Light Emitting Source
4
作者 Sameer Yadav 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第3期693-698,共6页
The Doppler effect is a phenomenon of intrinsic kinematic character. This paper analyzes the kinematic Doppler effect for the case where the source is moving and the observer is at rest in the classical limit. The par... The Doppler effect is a phenomenon of intrinsic kinematic character. This paper analyzes the kinematic Doppler effect for the case where the source is moving and the observer is at rest in the classical limit. The particle nature properties of radiation are considered and how it affects the dynamics of the Source has been studied. The dynamical and kinematical equations have been derived by considering this effect. It has been conclusively shown that a moving light-emitting source experiences a finite recoil momentum in the direction opposite to the direction of motion and come to rest in finite time. 展开更多
关键词 Doppler Effect Light Emission Frequency Shift Recoil Momentum
下载PDF
Hydrate capture CO_2 from shifted synthesis gas, flue gas and sour natural gas or biogas 被引量:10
5
作者 Yanhong Wang Xuemei Lang Shuanshi Fan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第1期39-47,共9页
CO2 capture by hydrate formation is a novel gas separation technology, by which CO2 is selectively engaged in the cages of hydrate and is separated with other gases, based on the differences of phase equilibrium for C... CO2 capture by hydrate formation is a novel gas separation technology, by which CO2 is selectively engaged in the cages of hydrate and is separated with other gases, based on the differences of phase equilibrium for CO2 and other gases. However. rigorous temperature and pressure, high energy cost and industrialized hydration separator dragged the development of the hydrate based CO2 capture. In this paper, the key problems in CO2 capture from the different sources such as shifted synthesis gas, flue gas and sour natural gas or biogas were analyzed. For shifted synthesis gas and flue gas, its high energy consumption is the barrier, and for the sour natural gas or biogas (CO2/CH4 system), the bottleneck is how to enhance the selectivity of CO2 hydration. For these gases, scale-up is the main difficulty. Also, this paper explored the possibility of separating different gases by selective hydrate formation and reviewed the progress of CO2 separation from shifted synthesis gas, flue gas and sour natural gas or biogas. 展开更多
关键词 clathrate hydrate: C02 capture hydrogen shifted synthesis gas flue gas sour natural gas or biogas
下载PDF
Carrier phase shifted SPWM based on current sourced multi-modular converter for active power filter 被引量:5
6
作者 王立乔 李建林 张仲超 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期861-866,共6页
A novel current-source active power filter (APF) based on multi-modular converter with carrier phase-shifted SPWM (CPS-SPWM) technique is proposed. With this technique, the effect of equivalent high switching frequenc... A novel current-source active power filter (APF) based on multi-modular converter with carrier phase-shifted SPWM (CPS-SPWM) technique is proposed. With this technique, the effect of equivalent high switching frequency con-verter is obtained with low switching frequency converter. It is very promising in current-source APF that adopt super-conducting magnetic energy storage component. 展开更多
关键词 Current sourced multi-modular converter Carrier phase shifted SPWM Active power filter
下载PDF
Laser Cooling and Deceleration of Neutral Atoms by Red-Shifted Diffuse Light 被引量:2
7
作者 CHEN Hongxin CAI Weiquan +3 位作者 LIU Liang SHU Wei LI Fosheng WANG Yuzhu 《Chinese Physics Letters》 SCIE CAS CSCD 1994年第9期541-544,共4页
We report a cooling and deceleration experiment of a thermal beam by using a nearly resonant red-shifted diffuse light in an optical integral sphere cavity.By using of this red-shifted diffuse light,the velocity of a ... We report a cooling and deceleration experiment of a thermal beam by using a nearly resonant red-shifted diffuse light in an optical integral sphere cavity.By using of this red-shifted diffuse light,the velocity of a part of thermal sodium atoms is cooled to 380m/s and the velocity width of cooled atoms is about 18m/s.The mechanism of this kind of laser cooling and the experimental results are discussed. 展开更多
关键词 cavity. shifted THERMAL
下载PDF
NUMERICAL SIMULATION FOR SHAPE OF COLD ROLLING ALUMINUM STRIP ON 4-HIGH MILL WITH ROLL SHIFTED 被引量:1
8
作者 Hongxu, Wang Jianjun, Liu +1 位作者 Jiachuang, Lian Junbo, Liu 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第3期30-36,共7页
1INTRODUCTIONAsthemilwithrolshiftedhasgoodshapecontrolcharacteristic,ithasbeenappliedtoproductionofcoldrol... 1INTRODUCTIONAsthemilwithrolshiftedhasgoodshapecontrolcharacteristic,ithasbeenappliedtoproductionofcoldroledandhotroledstri... 展开更多
关键词 MILL with ROLL shifted least square and COLLOCATION METHOD variation METHOD SHAPE
下载PDF
A Multiple Phase-Shifted Distributed Feedback(DFB)Laser Fabricated by Nanoimprint Lithography 被引量:1
9
作者 ZUO Qiang ZHAO Jian-Yi +6 位作者 CHEN Xin WANG Zhi-Hao SUN Tang-You ZHOU Ning ZHAO Yan-Li XU Zhi-Mou LIU Wen 《Chinese Physics Letters》 SCIE CAS CSCD 2013年第5期67-69,共3页
Multiple phase-shifted(MPS)diffraction grating is an effective way proposed to overcome the spatial hole burning(SHB)effect in a distributed feedback(DFB)laser.We present two symmetric λ/8 phase-shifted DFB lasers by... Multiple phase-shifted(MPS)diffraction grating is an effective way proposed to overcome the spatial hole burning(SHB)effect in a distributed feedback(DFB)laser.We present two symmetric λ/8 phase-shifted DFB lasers by using nanoimprint lithography(NIL).The threshold current of a typical laser is less than 15 mA.The side mode suppression ratio(SMSR)is still above 42 dB even at 100 mA current injection.To show the versatility of NIL,eight different wavelength MPS-DFB lasers on this single chip are also demonstrated.Our results prove that NIL is a promising tool for fabricating high performance complex grating DFB lasers. 展开更多
关键词 LITHOGRAPHY shifted OVERCOME
下载PDF
Design of Time-Resolved Shifted Dual Transmission Grating Spectrometer for the X-Ray Spectrum Diagnostics 被引量:1
10
作者 王保清 易涛 +6 位作者 王传珂 朱效立 李廷帅 李晋 刘慎业 江少恩 丁永坤 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第7期781-785,共5页
A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which... A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which has two sub transmission gratings with different line densities, of 2000 lines/mm and 5000 lines/mm. The axes of the two sub transmission gratings in SDTG are horizontally and vertically shifted a certain distance to measure a broad range of 0.1-5 keV time-resolved X-ray spectra. The SDTG has been calibrated with a soft X-ray beam of the synchrotron radiation facility and its diffraction efficiency is also measured. The designed SDTGS can take full use of the space on a record panel and improve the precision for measuring spatial and temporal spectrum simultaneously. It will be a promising application for accurate diagnosis of the soft X-ray spectrum in inertial confinement fusion. 展开更多
关键词 shifted dual transmission grating spectrometer GRATING X-ray spectra diag-nosis of the soft X-ray spectrum
下载PDF
Torque Calculation of Five-Phase Synchronous Reluctance Motors With Shifted-Asymmetrical-Salient-Poles Under Saturation Condition 被引量:2
11
作者 Qian Chen Xuping Shi +1 位作者 Gaohong Xu Wenxiang Zhao 《CES Transactions on Electrical Machines and Systems》 CSCD 2020年第2期105-113,共9页
In traditional analytical method(AM),the magnetic saturation is always ignored to simplify the calculation process.However,synchronous reluctance motors(SynRMs)often operate around saturation point to achieve higher t... In traditional analytical method(AM),the magnetic saturation is always ignored to simplify the calculation process.However,synchronous reluctance motors(SynRMs)often operate around saturation point to achieve higher torque density.Therefore,a new AM is proposed,in which the saturation of stator iron has been considered.The key of the proposed method includes a saturation factor,and an iterative method is adopted to compute the saturation factor in the SynRM by increasing the air-gap length.Especially,the proposed AM can be applied to a SynRM even with shifted-asymmetrical-salient-poles.In the process of AM,the expression of stator magnetomotive force(MMF)is built firstly.Additionally,the air-gap density including slotting effect and salient-poles is calculated.Then,the rotor MMF under saturation of the stator iron is obtained.Therefore,the precision of the instantaneous torque can be improved significantly.Eventually,by the verification of finite elements method(FEM)and experiments,the torque performance of SynRMs with shifted asymmetrical rotor can be predicted accurately by the proposed AM. 展开更多
关键词 Synchronous reluctance motors TORQUE shifted asymmetrical salient pole analytical method saturation.
下载PDF
Three-Variable Shifted Jacobi Polynomials Approach for Numerically Solving Three-Dimensional Multi-Term Fractional-Order PDEs with Variable Coefficients
12
作者 Jiaquan Xie Fuqiang Zhao +1 位作者 Zhibin Yao Jun Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第4期67-84,共18页
In this paper,the three-variable shifted Jacobi operational matrix of fractional derivatives is used together with the collocation method for numerical solution of threedimensional multi-term fractional-order PDEs wit... In this paper,the three-variable shifted Jacobi operational matrix of fractional derivatives is used together with the collocation method for numerical solution of threedimensional multi-term fractional-order PDEs with variable coefficients.The main characteristic behind this approach is that it reduces such problems to those of solving a system of algebraic equations which greatly simplifying the problem.The approximate solutions of nonlinear fractional PDEs with variable coefficients thus obtained by threevariable shifted Jacobi polynomials are compared with the exact solutions.Furthermore some theorems and lemmas are introduced to verify the convergence results of our algorithm.Lastly,several numerical examples are presented to test the superiority and efficiency of the proposed method. 展开更多
关键词 Three-variable shifted Jacobi polynomials multi-term FRACTIONAL-ORDER PDES VARIABLE coefficients numerical solution convergence analysis
下载PDF
Researted FOM for Multiple Shifted Linear Systems
13
作者 李占稳 汪勇 顾桂定 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期107-113,共7页
The seed method is used for solving multiple linear systems A (i)x (i) =b (i) for 1≤i≤s, where the coefficient matrix A (i) and the right-hand side b (i) are different in general. It is known that the CG meth... The seed method is used for solving multiple linear systems A (i)x (i) =b (i) for 1≤i≤s, where the coefficient matrix A (i) and the right-hand side b (i) are different in general. It is known that the CG method is an effective method for symmetric coefficient matrices A (i). In this paper, the FOM method is employed to solve multiple linear sy stems when coefficient matrices are non-symmetric matrices. One of the systems is selected as the seed system which generates a Krylov subspace, then the resi duals of other systems are projected onto the generated Krylov subspace to get t he approximate solutions for the unsolved ones. The whole process is repeated u ntil all the systems are solved. 展开更多
关键词 multiple linear systems seed method Krylov subspace FOM shifted systems.
下载PDF
Reciprocal transformations of the space-time shifted nonlocal short pulse equations
14
作者 Jing Wang Hua Wu Da-Jun Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第12期14-19,共6页
Reciprocal transformations of the space-time shifted nonlocal short pulse equations are elaborated.Covariance of dependent and independent variables involved in the reciprocal transformations is investigated.Exact sol... Reciprocal transformations of the space-time shifted nonlocal short pulse equations are elaborated.Covariance of dependent and independent variables involved in the reciprocal transformations is investigated.Exact solutions of the space-time shifted nonlocal short pulse equations are given in terms of double Wronskians.Realness of independent variables involved in the reciprocal transformations is verified.Dynamics of some obtained solutions are illustrated. 展开更多
关键词 reciprocal transformation space-time shifted nonlocal short pulse equation covariance of variable solution
下载PDF
Analysis of a novel phase-shifted soft switch converter
15
作者 蒋志宏 黄立培 张义 《China Welding》 EI CAS 2002年第1期67-71,共5页
In this paper, on the basis of the phase shifted controlled zero voltage switch (ZVS) full bridge converter with pulse width modulation (PWM), a novel zero voltage and zero current switch (ZVZCS) PWM converter u... In this paper, on the basis of the phase shifted controlled zero voltage switch (ZVS) full bridge converter with pulse width modulation (PWM), a novel zero voltage and zero current switch (ZVZCS) PWM converter using a simple auxiliary circuit was designed. The ZVZCS soft switch is achieved by the resonance among the resisting electromagnetic deflection capacitor, the capacitor of the simple auxiliary network and the leakage inductor of transformer. There are no dissipation devices of the saturation inductor and the auxiliary switch in the converter, meantime the capacitor of the auxiliary circuit is also used to clamp the voltage of the rectifier, and there is no additional clamped circuit. There is no big circulating current in the converter, all the active and passive devices work on the condition of the low current and voltage stress, and the proposed converter has wide load range and small duty loss. 展开更多
关键词 PHASE shifted control ZERO voltage and zero current switch
下载PDF
Existence of Many Blue Shifted Galaxies in the Universe by Dynamic Universe Model Came True
16
作者 Satyavarapu Naga Parameswara Gupta 《Open Journal of Modelling and Simulation》 2017年第1期113-144,共32页
There are many blue shifted Galaxies in our universe. Here we will see old simulations to make such predictions from the output graphs using SITA simulations. There are four new simulations also presented here. In the... There are many blue shifted Galaxies in our universe. Here we will see old simulations to make such predictions from the output graphs using SITA simulations. There are four new simulations also presented here. In these sets of simulations, different point masses are placed in different distances in a 3D Cartesian coordinate grid;and these point masses are allowed to move on universal gravitation force (UGF) acting on each mass at that instant of time at its position. The output pictures depict the three dimensional orbit formations of point masses after some iterations. In an orbit so formed, some Galaxies are coming near (Blue shifted) and some are going away (Red shifted). In this paper, the simulations predicted the existence of a large number of Blue shifted Galaxies, in an expanding universe, in 2004 itself. Over 8300 blue shifted galaxies have been discovered extending beyond the Local Group by Hubble Space Telescope (HST) in the year 2009. Thus Dynamic Universe model predictions came true. 展开更多
关键词 DYNAMIC UNIVERSE Model Blue shifted GALAXIES HUBBLE Space Telescope (HST) SITA Simulations
下载PDF
Spin and pseudospin symmetries of the Dirac equation with shifted Hulthe′n potential using supersymmetric quantum mechanics
17
作者 Akpan N. Ikot Elham Maghsoodi +2 位作者 Eno J. Ibanga Saber Zarrinkamar Hassan Hassanabadi 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期74-81,共8页
In this paper, we obtain approximate analytical solutions of the Dirac equation for the shifted Hulthén potential within the framework of spin and pseudospin symmetry limits for arbitrary spin–orbit quantum numb... In this paper, we obtain approximate analytical solutions of the Dirac equation for the shifted Hulthén potential within the framework of spin and pseudospin symmetry limits for arbitrary spin–orbit quantum number κ using the supersymmetry quantum mechanics. The energy eigenvalues and the corresponding Dirac wave functions are obtained in closed forms. 展开更多
关键词 Dirac equation supersymmetry method spin and pseudospin symmetries shifted Hulthén potential
下载PDF
Realization of a Nine-Level Cascaded NPC/H-Bridge PWM Inverter Using Phase-Shifted Carrier PWM Technique
18
作者 Tom Wanjekeche Dan Valentin Nicolae Adisa Abdul Jimoh 《Journal of Energy and Power Engineering》 2012年第8期1335-1342,共8页
Cascaded H-Bridge inverter has been researched for the past two decades, but there are no explicit guidelines on how one can realize a cascaded NPC (neutral-point-clamped)/H-Bridge inverter. Past research has also c... Cascaded H-Bridge inverter has been researched for the past two decades, but there are no explicit guidelines on how one can realize a cascaded NPC (neutral-point-clamped)/H-Bridge inverter. Past research has also concentrated on realizing a five-level NPC/H-Bridge inverter. This fails to address the principle of realizing a general cascaded N-level NPC/H-Bridge PWM inverter. This paper proposes an improved topology for achieving a nine-level cascaded NPC (neutral-point-clamped) H-Bridge inverter with reduced harmonic content. This new proposed topology requires a lesser number of separate dc sources as compared to conventional cascaded H-Bridge inverter. The whole system is considered as having four three level legs having two positive and two negative legs. By properly phase shifting the modulating wave and carriers, a nine-level output is achieved. A theoretical harmonic analysis of the proposed inverter is carried out based on double Fourier principle. The theoretical results are verified through MATLAB simulation. 展开更多
关键词 Harmonic content NPC/H-Bridge PWM inverter phase shifted carrier PWM technique three level inverter.
下载PDF
Global Power Structure Shifted and Transitional Multi-polarity Emerged
19
作者 Prof.YU Zhengliang is senior research fellow of Shanghai Institutes for International Studies. 《国际展望》 2010年第4期1-13,共13页
The world is facing the third important global power shift.The United States,EU, Japan,Russia,China,and the newly emerging power group are becoming the six big forces in the international center stage,while the former... The world is facing the third important global power shift.The United States,EU, Japan,Russia,China,and the newly emerging power group are becoming the six big forces in the international center stage,while the former three forces and the latter three belong to two groups,waning and waxing respectively.The major shift in the global balance of power is bound to give rise to the transitional multi-polar configuration,which implies a shifting of leadership over the configuration,China and U.S.outweighing other forces,global issues looming large,homogeneity blending with heterogeneity,and a shifting center of world powers.The transitional multi-polar configuration is all about change,upon which China is one of the decisive forces. 展开更多
关键词 Global Power Structure shifted and Transitional Multi-polarity Emerged
下载PDF
Ultraviolet and mid-infrared continuum generation by cross-phase modulation between red-shifted solitons and blue-shifted dispersive waves in a photonic crystal fiber 被引量:1
20
作者 申向伟 苑金辉 +7 位作者 桑新柱 余重秀 饶岚 忻向军 夏民 韩颖 夏长明 侯蓝田 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期337-342,共6页
Using a photonic crystal fiber with a zero dispersion wavelength of the fundamelItal mode at 780 nm designed and fabricated in our lab, the ultraviolet and mid-infrared continua are generated by cross-phase modulation... Using a photonic crystal fiber with a zero dispersion wavelength of the fundamelItal mode at 780 nm designed and fabricated in our lab, the ultraviolet and mid-infrared continua are generated by cross-phase modulation between red-shift solitons and blue-shift dispersive waves. The dependences of continuum on the pump power and wavelength are investigated. With the pump working at 820 nm, when the pump power increases froul 300 to 500 mW, the bandwidths of ultraviolet and mid-infrared continua change from 80 to 140 nm and 100 to 200 nm, respectively. The wavelength of ultraviolet continuum is below 246 nm, and the wavelength of mid-infrared continuum exceeds 2500 nm. Moreover, the influences of pump power on wavelength and conversion efficiency of different parts of continua are also demonstrated. 展开更多
关键词 photonic crystal fiber (PCF) ultraviolet and mid-infrared continuum fundamentalmode soliton self-frequency shift
下载PDF
上一页 1 2 129 下一页 到第
使用帮助 返回顶部