维普中文期刊产品整合服务
35267篇 您的检索式:期刊名="Institute"
    题名 作者 年代 出处 被引量
1Lagrange系统的形式不变性(英文)显示文摘研究Lagrange系统的形式不变性 .用Lagrange方程在无限小变换下的形式不变性 ,给出形式不变性的定义和判据 .建立形式不变性与Noether对称性之间的关系 .梅凤翔 2000Journal of Beijing Institute of Technology2000,9,2:56
2Structure and Mechanical Properties of Magnesium Alloy Treated by Plasma Electrolysis Oxidation Using Direct Current and High-frequency Bipolar Pulsing Modes显示文摘JIN Fanya Chu Paul K. XU Guidong ZHAO Jun SHEN Liru TONG Honghui 2006Southwestern Institute of Physics Annual Report2006,,1:29
3Modified Two-Degrees-of-Freedom Internal Model Control for Non-Square Systems with Multiple Time Delays显示文摘A modified two-degrees-of-freedom( M-TDOF) internal model control( IMC) method is proposed for non-square systems with multiple time delays and right-half-plane( RHP) zeros. In this method,pseudo-inverse is introduced to design the internal model controller,and a desired closed-loop transfer function is designed to eliminate the unrealizable factors of the derived controller. In addition,set-point tracking and load-disturbance rejection of each process are separately controlled by two controllers. The simulation results show that in addition to high decoupling performance and robustness,the proposed control method also effectively improves loaddisturbance rejection and simultaneously optimizes the input tracking performance and disturbance rejection performance by selecting the parameters of controllers. Furthermore,the higher tolerance of model mismatch is achieved in this paper.Jian-Chang Liu Nan Chen Xia Yu 2014Journal of Harbin Institute of Technology(New Series)2014,21,2:25
4Method of Improving the Navigation Accuracy of SINS by Continuous Rotation显示文摘A method of improving the navigation accuracy of strapdown inertial navigation system (SINS) is studied. The particular technique discussed involves the continuous rotation of gyros and accelerometers cluster about the vertical axis of the vehicle. Then the errors of these sensors will have periodic variation corresponding to components along the body frame. Under this condition, the modulated sensor errors produce reduced system errors. Theoretical analysis based on a new coordinate system defined as sensing frame and test results are presented, and they indicate the method attenuates the navigation errors brought by the gyros’ random constant drift and the accelerometer’s bias and their white noise compared to the conventional method.杨勇 缪玲娟 沈军 2005Journal of Beijing Institute of Technology2005,14,1:22
5Multi-constrained model predictive control for autonomous ground vehicle trajectory tracking显示文摘A multi-constrained model predictive control(MPC)algorithm for trajectory tracking of an autonomous ground vehicle is proposed and tested in this paper.First,to simplify the computation,an active steering linear error model is applied in the MPC controller.Then,a control increment constraint and a relaxing factor are taken into account in the objective function to ensure the smoothness of the trajectory,using a softening constraints technique.In addition,the controller can obtain optimal control sequences which satisfy both the actual kinematic constraints and the actuator constraints.The circular trajectory tracking performance of the proposed method is compared with that of another MPC controller.To verify the trajectory tracking capabilities of the designed controller at different desired speed,the simulation experiments are carried out at the speed of 3m/s,5m/s and 10m/s.The results demonstrate the MPC controller has a good speed adaptability.龚建伟 徐威 姜岩 刘凯 郭红芬 孙银健 2015Journal of Beijing Institute of Technology2015,24,4:19
6车辆运动状态下SINS的初始对准技术(英文)显示文摘对车辆运动状态下捷联惯导系统的初始对准技术进行研究 .以里程计作为外部传感器 ,建立了运动状态下初始对准的数学模型 ,分析了系统状态的可观测性 ,并进行了仿真研究 .结果表明 ,捷联惯导系统只要求短时间内(几秒钟 )车辆处于静止状态 ,以进行解析式粗对准 ,之后车辆就可以向预定地点行驶 ,1 0min内即可在运动状态下完成精对准 。缪玲娟 沈军 刘伟 杨勇 2002Journal of Beijing Institute of Technology2002,11,3:17
7Dynamics model of underwater robot motion control in 6 degrees of freedom显示文摘In order to analyze underwater robot control system dynamics features, a system 6-DOF dynamics model was founded. Underwater robot linear and nonlinear hydrodynamics were analyzed by Taylor series, based on general motion equation. Special control system motion equation was deduced by cluster of inertial items and non-inertial items. For program convenience, motion equation matrix format was presented. Experimental principles of screw propellers, rudders and wings were discussed. Experimental data least-square curve fitting, interpolation and their corresponding traditional equation helped us to obtain the whole system dynamic response procedure. A series of simulation experiments show that the dynamics model is correct and reliable. The model can provide theory proof for analyzing underwater robot motion control system physics characters and provide a mathematic model for traditional control method.李晔 刘建成 沈明学 2005Journal of Harbin Institute of Technology(New Series)2005,12,4:17
8Digital Image Scrambling Technology Based on the Symmetry of Arnold Transform显示文摘An improved digital image scrambling method based on Arnold transform is proposed. The method can be used for the rectangle image by splitting rectangle image into several square images. Furthermore,a pretreatment is added to speeding up the process and enhancing the scrambling effect. The recovering of the scrambled image depends on the reverse Arnold transform that has the same cycle times with the Arnold transform. The recovering is lossless and need not calculating the period of the Arnold transform. Finally, experimental results show the robustness of the method.杨雅丽 蔡娜 倪国强 2006Journal of Beijing Institute of Technology2006,15,2:16
9Toward a Harmonious Unifying Hybrid Model for any Evolving Complex Networks显示文摘The basic concept and method for the HUHPM can be expressed in Fig. 1. This means that the HUHPM can rest on any type of network’s original growth way and RPAFANG Jin-qing, BI Qiao, LI Yong, LU Xin-biao, LIU Qiang 2007Annual Report of China Institute of Atomic Energy2007,,1:16
10光纤陀螺漂移的数据分析及建模(英文)显示文摘设计了应用于陆用捷联惯导系统中的干涉式光纤陀螺 (IFOG)的数据采集系统 ,对IFOG进行了测试 ,给出了测试曲线 .采用Allan方差法对IFOG的测试数据进行了分析 ,辨识出了各项随机误差系数 .此外 ,采用时间序列分析方法 ,建立了IFOG的随机漂移误差模型 .所得结论为改进IFOG设计及实际应用中对IFOG的误差补偿奠定了基础 .缪玲娟 张方生 沈军 刘伟 2002Journal of Beijing Institute of Technology2002,11,1:16
11捷联惯导误差分析与误差补偿(英文)显示文摘通过误差分析 ,讨论了各种误差源对捷联惯导系统的影响 .根据惯导系统精度要求 ,确定了惯性测量元件最大允许误差 ,从而为选择合理的传感器确定了理论依据 .这些传感器组成的惯性测量元件需要经过标定实验来确定系统误差补偿模型中的系数 .误差补偿后 ,通过均匀设计法得到系统精度 ,满足了精度要求 .刘勤 刘莉 祁载康 2002Journal of Beijing Institute of Technology2002,11,2:16
12Elastic Field of a Straight Dislocation in One-Dimensional Hexagonal Quasicrystals显示文摘目的研究准晶中的位错弹性理论.方法通过将位错分解为刃型和螺型分量,该位错引起的整个弹性场可由两个分量所引起的弹性场叠加得到.结果与结论获得了平行于准周期轴的直位错的弹性场及两个平行的直螺型位错之间的广义PeachKoehler力。李显方 孙应飞 范天佑 1999Journal of Beijing Institute of Technology1999,8,1:15
13A Novel Combination of Immunoreaction and ICP-MS as a Hyphenated Technique for the Determination of Thyroid-stimulating Hormone (TSH) in Human Serum显示文摘The novel coupling method based on the hyphenation of immunoreaction with ICP-MS is developed and applied to the determination of thyroid-stimulating hormone (TSH) in human serum. In this system, TSH is firstly captured by anti-TSH monoclonal antibodies immobilized on a solid support. Biotinylated anti-TSH monoclonal antibodies and Eu3+-labelled streptavidin are then added to form the complex capturing andbody-TSH-biotinylated anti-TSH antibody-Eu3+-labeled streptavidin. After unbound reactants are washed away, Eu3+ bound to the complex is extractedZHANG Chao, WU Feng-bo, ZHANG Yan-yan, WANG Xin, ZHANG Xin-rong(Department of Chemistry, Tsinghua University, 100084 Third Hospital of Peking University, 100083) 2001Annual Report of China Institute of Atomic Energy2001,,0:14
14Cross-Layer Adaptive Resource Allocation Algorithm with Diverse QoS Requirements for Single-Cell OFDMA Systems显示文摘The orthogonal frequency division multiple access( OFDMA) based communication system has been considered as the main trend of next-Generation communication system. But the existing resource allocation algorithm designed for such system is always with high complexity thus hard to be realized. To solve such problem with the constraints of spectrum efficiency and buffer state,a novel cross-layer resource allocation algorithm( RAA) is proposed in this paper. The goal of our RAA is to maximize the system throughput while satisfying several practical constraints,such as fairness among services,head of line( Ho L) delay and diverse quality of service( Qo S) requirements. Due to these constraints,finding the optimal solution becomes a NPhard problem. Therefore in this paper a novel method to solve such problem with acceptable complexity is proposed within following steps: firstly,based on the link state we formulate the ideal subchannel allocation strategy as a convex optimization problem,which can be efficiently solved by our proposed lagrange multiplier technique subchannel allocation( LMTSA) algorithm; secondly,according to the obtained channel allocation matrix,a power allocation algorithm based on the water-filling power allocation( WPA) idea is deployed to get the optimal power allocation matrix combining with adaptive modulation and coding( AMC); finally,through a greedy algorithm,the ultimate subchannel and power allocation matrix can be obtained based on iterative method. The simulation results illustrate that we can achieve the higher throughput and better Qo S performance than the widely-used maximum throughput( MT) algorithm and round robin( RR) algorithm.Li Zeng Xi Li Hong Ji Ke Wang 2015Journal of Harbin Institute of Technology(New Series)2015,22,1:14
15基于模糊逻辑的AMT离合器结合控制研究(英文)显示文摘研究具有机械式自动变速器的履带式车辆起步时离合器结合控制问题 .通过建立车辆动力学和自动离合器的数学模型并采用Simulink仿真工具 ,研究了车辆起步时离合器平滑时间和冲击度等动态特性 .基于对仿真结果和驾驶员操作经验的分析 ,制定了车辆起步时离合器结合速度的模糊控制策略 .仿真表明该方法具有较好的控制特性 .汤霞清 侯朝桢 陈云窗 2002Journal of Beijing Institute of Technology2002,11,1:14
16Numerical Simulation of a Spark Ignited Two-Stroke Free-Piston Engine Generator显示文摘A numerical program is built to simulate the performance of a spark ignited two-stroke free-piston engine coupled with a linear generator.The computational model combines a series of dynamic and thermodynamic equations that are solved simultaneously to predict the performances of the engines.The dynamic analysis performed consists of an evaluation of the frictional force and load force introduced by the generator.The thermodynamic analysis used a single zone model to describe the engine's working cycle which includes intake,scavenging,compression,combustion and expansion,and to evaluate the effect of heat transfer based on the first law of thermodynamics and the ideal gas state equation.Because there is no crankshaft,a time based Wiebe equation was used to express the fraction of fuel burned in the combustion.The calculated results were validated by using the experimental data from another research group.The results indicate that the free-piston generator has some advantages over conventional engines.毛金龙 左正兴 刘栋 2009Journal of Beijing Institute of Technology2009,18,3:13
17The Measurement of ^(41)Ca and Its Application for Cell Messenger显示文摘Ca is an important element in human body. Many diseases relate with Ca in organizations and cells.41Ca (T1/2=1.04×105 a, pure electron capture with emission or Auger electrons and X-rays) is an idealtracer to understand of the mechanism of the disease. The measurement of 41Ca with AMS has been usedfor study of long-term bone resorption, bone resorption in a human, Ca uptake and deposition in heardtissue and skeletal Ca metabolism. Ca2+ in cytoplasm of human cell as a cell messenger plays anS. JIANG, M. HE, K. DONG, D. YUE, S. WU, G.XU, J.QIN, Q.YOU, Y.ZHENG, Y.GUAN, Q. LIANG, X. ZHAO, Q. WANG S. LIU(Department of Nuclear Physics, C1AE, Beijing 102413, China Department of biology, Beijing Normal University, Beijing 100875, China Department of Physics, Guangxi University, Nanning 530004, China College of Public Health, Beijing University, Beijing 100083, China College of Applied Arts and Science, Beijing Union University, Beijing 100083, China) 2002Annual Report of China Institute of Atomic Energy2002,,0:12
18Feature Extraction of Symmetrical Triangular LFMCW Signal Using Wigner-Hough Transform显示文摘Feature extraction of symmetrical triangular linear frequency modulation continu ous wave (LFMCW) signal is studied. Combined with its peculiar characteristics, a novel algorithm based on Wigner-Hough transform (WHT) is presented for the de tection and parameter estimation of this type of waveform. The initial frequency and chirp rate of each segment of this wave are estimated, and the peak-value searching steps in the parameter space is given. Compared with Wigner-Ville dis tribution (WVD), Pseudo-Wigner-Ville distribution (PWD) and Smoothed-Peseudo -Wigner-Ville distribution (SPWD), WHT has proven itself to be the best method for feature extraction of symmetrical triangular LFMCW signal. In the end, Mont e-Carlo simulations under different SNRs are carried out, with validating resul ts on this method.刘锋 徐会法 孙大鹏 陶然 王越 2009Journal of Beijing Institute of Technology2009,18,4:12
19Applications of Skyrme Energy-Density Functional to Fusion Reactions Spanning Fusion Barriers显示文摘A large number of fusion excitation functions have been accumulated in recent decades, which provides a possibility for a systematic study on the fusion reactions. Newton et al. analyzed a total of 46 fusion excitation functions at energies above the average fusion barriers using the Woods-Saxon formLIU Min,WANG Ning,LI Zhu-xia,WU Xi-zhen 2006Annual Report of China Institute of Atomic Energy2006,,1:12
20Modeling and simulation of JWL equation of state for reactive Al/PTFE mixture显示文摘An analytical method is presented to fit parameters of Jones-Wilkins-Lee(JWL) equation of state(EOS) for the chemical process of aluminum-polytetrafluoroethylene(Al/PTFE) mixture.Subroutine codes for both strength model and EOS were developed in explicit-FE code AUTODYN.Firstly,the shock Hugoniot data of reactive Al/PTFE mixture was analytically derived by implementing this methodology.The JWL EOS was verified to fit shock Hugoniot data of both reacted and unreacted Al/PTFE mixture,which gives reasonable results.Furthermore,to numerically ascertain the reaction phases of ignition and growth and quasi detonation of Al/PTFE mixture,characterized experiment was setup to validate the reaction phases and coefficients of JWL EOS for Al/PTFE mixture.From the test,a promising example of reactive mixture Al/PTFE is capable to enhance lethality of weapons,the status computation in clude quasi-detonation pressure and temperature of Al/PTFE mixture in different chemical reaction phases is validated.蒋建伟 王树有 张谋 魏强 2012Journal of Beijing Institute of Technology2012,21,2:12
返回顶部 每页显示:
共1764页 首页 上一页 第1页 下一页 末页 /1764 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费