检索结果-内蒙古大学图书馆

2016 IEEE/CSAA International Conference on Aircraft Utility Systems(AUS)

作者： Chao Hu Pengfei Zhang Xiaoping Ouyang Houtao Ku Qinghe Zhou Enxiao Zhang State Key Lab.of Fluid Power Transmission and Control Zhejiang University Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration State Key Lab.of Fluid Power Transmission and Control Zhejiang Univ. The High School Attached to Zhejiang University

Seal is one of the most important characteristics for cylinders and suitable seal configuration will guarantee the long life cycle of the seal and the *** is the only way which can demonstrate the best seal configuration in *** this paper,one approach is brought forward for testing the seal performance of cylinders with different seals configurations at the same load working condition for saving the test *** the test-rig,the synchronization of cylinders is one of the key *** test system is modelled in the AMESim *** effect caused by the changes of the different physical parameters is analyzed,such as load stiffness,viscous damping coefficient of cylinder,dead volume of cylinder and internal leakage *** experiment is carried out and test results agree with the simulation ***,the appropriate solution is proposed for improving the synchronization of the multi-cylinders further.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Investigation into influence factors of synchronous movement of multi-cylinders

Investigation into influence factors of synchronous movement...

引用

IEEE International Conference on Aircraft Utility Systems (AUS)

作者： Chao Hu Pengfei Zhang Xiaoping Ouyang Houtao Ku Qinghe Zhou Enxiao Zhang State Key Lab. of Fluid Power Transmission and Control Zhejiang University Hangzhou China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing China The High School Attached to Zhejiang University Hangzhou China

ISBN: (纸本)9781509010882

Seal is one of the most important characteristics for cylinders and suitable seal configuration will guarantee the long life cycle of the seal and the cylinder. Experiment is the only way which can demonstrate the best seal configuration in applications. In this paper, one approach is brought forward for testing the seal performance of cylinders with different seals configurations at the same load working condition for saving the test time. In the test-rig, the synchronization of cylinders is one of the key technologies. The test system is modelled in the AMESim software. The effect caused by the changes of the different physical parameters is analyzed, such as load stiffness, viscous damping coefficient of cylinder, dead volume of cylinder and internal leakage coefficient. The experiment is carried out and test results agree with the simulation results. Finally, the appropriate solution is proposed for improving the synchronization of the multi-cylinders further.

关键词： Synchronization Valves Seals Damping Load modeling Springs Servomotors

来源：评论

学校读者我要写书评

暂无评论

Temperature and electric-field induced phase transitions, and full tensor properties of C-poled domain-engineered tetragonal 0.63Pb(Mg1/3Nb2/3)−0.37PbTiO3 single crystals

引用

Physical Review B 2016年第9期93卷 094104-094104页

作者： Limei Zheng Yujia Jing Xiaoyan Lu Ruixue Wang Gang Liu Weiming Lü Rui Zhang Wenwu Cao Condensed Matter Science and Technology Institute Harbin Institute of Technology Harbin 150080 China Key Laboratory of Structures Dynamic Behavior and Control of the Ministry of Education School of Civil Engineering Harbin Institute of Technology Harbin 150001 China Center for High Pressure Science and Technology Advanced Research Shanghai 201203 China Department of Mathematics Materials Research Institute The Pennsylvania State University University Park Pennsylvania 16802 USA

The phase-transition sequence of 0.67Pb(Mg1/3Nb2/3)−0.37PbTiO3 (PMN-0.37PT) single crystals driven by the electric (E) field and temperature is comprehensively studied. Based on the strain-E field loop, polarization-E field loop, and the evolution of domain configurations, the E field along the [011]C induced phase transitions have been confirmed to be as follows: tetragonal (T) → monoclinic (MC)→ single domain orthorhombic (O) phase. As the E field decreases, the induced O phase cannot be maintained and transformed to the MC phase, then to the coexistence state of MC and T phases. In addition, the complete sets of dielectric, piezoelectric, and elastic constants for the [011]C-poled domain-engineered PMN-0.37PT single crystal were measured at room temperature, which show high longitudinal dielectric, piezoelectric, and electromechanical properties (ɛ33T=10661,d33=1052pC/N, and k33=0.766). Our results revealed that the MC phase plays an important role in the high electromechanical properties of this domain-engineered single crystal. The temperature dependence of the domain configuration revealed that the volume fraction of the MC phase decreases with temperature accompanied by the reduction of ɛ33T,d31, and k31 due to the substantially smaller intrinsic properties of the T phase.

关键词： Electric polarization Ferroelectricity Phase transitions Piezoelectricity Ferroelectrics Piezoelectrics Relaxor ferroelectrics Polarization

来源：评论

学校读者我要写书评

暂无评论

A Novel Accurate Localization Method of Vehicle-logo

A Novel Accurate Localization Method of Vehicle-logo

引用

2015 3rd International Conference on Machinery,Materials and Information technology Applications(ICMMITA 2015)

作者： Jin Liu De Cai Zhonghan Shi Jiahao Deng Key Laboratory of Electromechanical Dynamic Control School of Mechatronical Engineering Beijing Institute of Technology

Aiming at the problem lied in existed methods which cannot suppress grille background completely, a novel method of vehicle-logo accurate localization was proposed. Firstly color invariants and prior information are used for fast localizing license plate in RGB color space directly;and then process fine localization of the vehicle-logo based on coarsely localized results. Background noises are secondarily suppressed based on gradient angle histogram analysis and local self-adaptive threshold treatment. Numerous experiments show that this method possesses not only high accuracy but also high robustness in localization, as compared to classic template matching. Besides, the proposed method satisfies the requirement of real-time performance.

关键词： Vehicle-logo Accurate localization Gradient angle histogram analysis Local self-adaptive threshold

来源：评论

学校读者我要写书评

暂无评论

Three-dimension micro magnetic detector based on GMI effect

引用

Journal of Beijing Institute of technology 2014年第2期23卷 143-146页

作者：魏双成邓甲昊韩超杨雨迎 Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronics EngineeringBeijing Institute of Technology

The giant magneto-impedance（GMI）effect of amorphous wire was analyzed *** amorphous wire had strong GMI effect in the stimulation of sharp pulse of 680kHz and18 mV.A pulse generator was designed to provide high frequency pulse to a magnetic impedance（MI）*** induced voltage on the pickup coil wound on the amorphous wire was sampled and held with a detect circuit using analog switch.A stable magnetic sensor was constructed.A three-dimension micro magnetic field detector was designed with a central controller *** stability and sensitivity were obtained in the MI sensor with the detect *** results showed that the resolution of the detector was 1nT in the full scale of±2 Oe and the detector worked stably from the room temperature to about 80℃.A small ferromagnetic target was detected by the three-dimension detector in laboratory environment without magnetic *** target moving direction was ascertained with the wave shape of axis parallel in that direction.

关键词： giant magneto-impedance（GMI）effect amorphous wire three dimension detector pulse generator analog switch

来源：评论

学校读者我要写书评

暂无评论

A method to quickly predict dispersion for impact point of high spin rate projectile

A method to quickly predict dispersion for impact point of h...

引用

2015 Joint International Mechanical,Electronic and Information technology Conference(JIMET 2015)

作者： Xiao-lin Luo Science and Technology on Electormechanical Dynamic Control Laboratory Beijing Institute of Technology

ISBN: (纸本)9781510817982

A method for real time in flight prediction of the ground impact point and dispersion of indirect fire projectiles is investigated. A three degree of freedom projectile model solution is used to be determined the total dispersion of trajectory. With the root mean square method, mean point of impact error(MPI) of projectile is simulation. the final simulation verifies that the method proposed is use for determined the total dispersion of trajectory.

关键词： Precision Error Mean Point of Impact Error Monte Carlo analysis The Root Mean Square Method

来源：评论

学校读者我要写书评

暂无评论

Simulation of characteristics of cloud and fog echo for pluse laser fuze

引用

Guangxue Jingmi Gongcheng/Optics and Precision Engineering 2015年 23卷 1-7页

作者： Wang, Feng-Jie Chen, Hui-Min Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing100081 China

Pulse laser fuze is susceptible to the interference of natural environment, such as cloud and fog, and easy to produce a false alarm. Therefore, this paper researches the cloud and fog echo characteristics of the pulse laser fuze. On the basis of Mie scattering theory, a pulse laser transmission model for the cloud and fog is established by using Monte Carlo simulation. The cloud and fog echoes in two conditions are simulated. The first condition is that both pulse laser fuze and target are in the inside of cloud and fog, and the other is that the target is in the inside of cloud and fog and the pulse laser fuze in the outside. At the first condition, the echo signals are acquired when the distance between pulse laser fuze and target is 10 m and the visibility are 1, 3, 5 and 10 m, respectively. At the second condition, the dynamic echo characteristics are obtained when the distance between pulse laser fuze and target is 10 m, the visibility is 3 m and the cloud and fog boundaries are 0, 1, 3, 5, 7and 9 m, respectively. Moreover, it analyzes the influences of cloud and fog parameters and position, on the cloud and fog echo, and the waveform difference of cloud and fog echo and target echo. This research provides the theoretical support for the anti-interference of pulse laser fuzes. © 2015, Chinese Academy of sciences. All right reserved.

关键词： Monte Carlo methods

来源：评论

学校读者我要写书评

暂无评论

Research on leakage current test method

引用

仪器仪表学报 2014年第S2期35卷 219-223页

作者： Li Dong Wang Yanlin Beijing Key Laboratory of Electromechanical System Measurement and Control Beijing Information Science and Technology University

In the leakage current test, through the high speed data collection and digital filtering to the output voltage of the human body impedance network, leakage current test that is in accordance with many kinds of electrical safety standards can be realized, and the frequency distribution information of the leakage current can be got as well, which can be used to much more completely evaluate the possible damage degree of the leakage current to the human body and analyze the reason for the appearance of the leakage current in the electric equipment.

关键词： leakage current test human body imspedance network

来源：评论

学校读者我要写书评

暂无评论

Design and implementation of an FFT phase difference measuring method

Design and implementation of an FFT phase difference measuri...

引用

2014 International Conference on Sensors Instrument and Information technology, ICSIIT 2014

作者： Zhu, Xiong Wei Chen, Hui Min Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing 100081 China

ISBN: (纸本)9783038350392

The conventional phase difference measuring methods in the phase-shift laser range finder are usually implemented with complex hardware circuits and phase discrimination algorithm. In this paper an FFT phase difference measuring method is designed and implemented based on STM32F407VG microcontroller. This method takes the advantage of the pre-set and fixed frequency of the beat signal by setting the analog-to-digital conversion rate precisely and making the input data length of FFT integral multiples of the beat signal period. In this way spectrum correction is no need. The hardware circuits and phase discrimination algorithm is simplified. The test results show that the phase difference measuring accuracy of 1/12000 is achieved. © (2014) Trans Tech Publications, Switzerland.

关键词： Fast Fourier transforms

来源：评论

学校读者我要写书评

暂无评论

Thermodynamics study of laser detector with high rotation speed

Thermodynamics study of laser detector with high rotation sp...

引用

作者： Yue, M.H. Chen, H.M. Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing100081 China

In this paper, thermodynamics properties of a laser detector applied in 105 mm shrapnel with high rotation speed have been explored. In outer trajectory, aerodynamic heating usually generates because of viscosity, and this is strengthened by high rotation speed of the shrapnel. Thermal strain may occur, which will influence the overall power of the detector and shrapnel. The temperature has been computed by computational fluid dynamics method, and ANSYS Workbench has been applied to obtain thermal strain. In order to disclose the effect of rotation, comparison among simulation results in different conditions are carried out. It is figured out that the temperature increase does not exceed the limit of optical material (polymethyl methacrylate), so the function of laser detector and the power of shrapnel will not be affected. This paper demonstrates the feasibility of material choice of laser detector optical systems. It has important theoretical meaning and practical application value for the design of conventional ammunition laser detector. © 2014 W. S. Maney & Son Ltd.

关键词： Computational fluid dynamics

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：