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A Trajectory Tracking Control Method for Underactuated Surface Ships

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A Trajectory Tracking Control Method for Underactuated Surfa...

第24届中国控制与决策会议

作者： LIU Yang 1,2 , GUO Chen 1 1. College of Information Science and Technology, Dalian Maritime university, Dalian 116026, china2. school of Electronic and Information Engineering, Dalian Jiaotong university, Dalian 116028, china

We proposed a nonlinear control method for trajectory tracking of underactuated surface ship. The nonlinear hydrodynamic damp and sway velocity are included in the ship model, which can stand for high speed and low speed of the ship. In kinematics loop the reference yaw angle and the reference speed are given. The nonlinear controller is designed in dynamics loop to make the error variables asymptotically stable. The stability of the closed-loop system is analyzed by using Lyapunov theory. Simulation results illustrate the effectiveness of the proposed control method.

关键词： Underactuated Ship Trajectory Tracking Nonlinear Control Cascade system

Digital Filter for GPS/Rotary SINS Integrated Alignment

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Digital Filter for GPS/Rotary SINS Integrated Alignment

第三届中国卫星导航学术年会

作者： SUN Wei 1,2 , XU Aigong 1 , GAO Yang 1,2 1. school of Geomatics, Liaoning Technical university Fuxin, Liaoning Province, china 2. Department of Geomatics, Engineering university of Calgary Calgary, AB, Canada

Advanced development of Strapdown Inertial Navigation system （SINS） using Inertial Measurement Unit （IMU） rotational motion technology is described. Rotary SINS requires an initialization process that establishes the relationship between the IMU frame and the local geographic reference. This process, called alignment, generally used to estimate the initial attitude angles. The purpose of this project is to determine the feasibility of averaging out the inertial compo- nent bias in order to improve the accuracy of alignment. The traditional method of integrated alignment, which based on the assumption that GPS provide the same data repeatedly in a SINS’s cycle which limited the data’s accuracy, cannot satisfy the vehicle alignment requirement. The novel method is to determine the feasibility of exact data synchronization in loose integrated alignment in order to improve the accuracy and rapidity of alignment. In this approach, a digital high-pass filter, which implements a pre-filtering scheme of the measured signal, is used to filter the Schuler cycle of discrete velocity difference between the rotary SINS and GPS. We confirmed the validity of this approach to improve greatly the accuracy and the convergence time to satisfy the required accuracy from experiment results.

关键词： Rotary SINS GPS loose integrated alignment high-pass filter

Research on the Evaluation of Knowledge Management Performance of High-tech Enterprise

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Research on the Evaluation of Knowledge Management Performan...

2010 IEEE 2nd Symposium on Web Society

作者： Nan YANG school of Economics and Management Zhongyuan university of Technology Zhengzhou china

＜正＞The ultimately intention of knowledge management is to get the most income,it is necessary to measure the effect of knowledge management,thus the key problem of this study is how to evaluate the performance of knowledge management in High-tech *** on both case studies and model building,this paper analyzed the content and principle of the performance evaluation of knowledge management in High- tech Enterprise,and then established the evaluating index system of knowledge management performance and designed the evaluating method and *** gave the corresponding evaluation index weight by using expert evaluation method. Further,this paper made empirical research on the performance evaluation of knowledge management based on the fuzzy and comprehensive evaluation *** results can explain how the performance is after knowledge management and put forward to views of rectification at evaluation *** research of this paper provides essential theoretical method and tactical support for high-tech enterprises to implement effective knowledge management and enhance comprehensive competitiveness.

关键词： knowledge management performance evaluation high-tech Enterprise fuzzy and comprehensive evaluation

Personalized Learning system Based on Data Mining for Experimental Platforms

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Personalized Learning System Based on Data Mining for Experi...

2012 National Conference on Information Technology and Computer Science

作者： Zufeng Zhong school of Business,ZhanJiang Normal university,Zhanjiang,524048,china Hongyan Yang Chemistry science and technology school,ZhanJiang Normal university,Zhanjiang,524048,china

On the basis of adaptive learning and the results of data mining,a personalized learning system was designed and *** system on this algorithm has implemented the educative conception of teaching students in accordance with their *** platform in the traditional learning modules is joined into a personalized recommendation and the more modern individualized educational *** system can meet the learning demands of different students in any time.

关键词： personalized learning system data mining experimental platform of economics and management data source web log

Effects of bismuth on growth of intermetallic compounds in Sn-Ag-Cu Pb-free solder joints

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Transactions of Nonferrous Metals Society of china 2006年第S2期 739-743页

作者： LI Guo-yuan, SHI Xun-qing school of Materials Science and Engineering, Nanyang Technological university, Singapore 639798 Intel Technology Development Ltd, Shanghai 200131, china

The effects of Bi addition on the growth of intermetallic compound (IMC) formation in Sn-3.8Ag-0.7Cu solder joints were investigated. The test samples were prepared by conventional surface mounting technology. To investigate the element diffusion and the growth kinetics of intermetallics formation in solder joint, isothermal aging test was performed at temperatures of 100, 150, and 190℃, respectively. The optical microscope (OM) and scanning electron microscope (SEM) were used to observe microstructure evolution of solder joint and to estimate the thickness and the grain size of the intermetallic layers. The IMC phases were identified by energy dispersive X-ray (EDX) and X-ray diffractometer (XRD). The results clearly show that adding about 1.0% Bi in Sn-Ag-Cu solder alloy system can refine the grain size of the IMC and inhibit the excessive IMC growth in solder joints, and therefore improve the reliability of the Pb-free solder joints. Through observation of the microstructural evolution of the solder joints, the mechanism of inhibition of IMC growth due to Bi addition was proposed.

关键词： Sn-Ag-Cu alloy Pb-free solder intermetallics solder joint bismuth interconnects

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司法能动主义的中国化

法学论坛 2011年第6期26卷 117-122页

作者：王彬南开大学法学院天津300071

在美国宪政语境下,能动主义的司法哲学要求法官超越法律的文本含义解释法律,以满足公民不断产生的权利诉求和适应社会转型的现实,但是,美国宪政结构中的固有悖论使美国司法哲学处于民主与法治二律背反的宪政困境中,很难简单评判司法能... 详细信息

在美国宪政语境下,能动主义的司法哲学要求法官超越法律的文本含义解释法律,以满足公民不断产生的权利诉求和适应社会转型的现实,但是,美国宪政结构中的固有悖论使美国司法哲学处于民主与法治二律背反的宪政困境中,很难简单评判司法能动和司法克制孰优孰劣。在中国语境下,传统的法律文化为实行司法能动提供充分的文化土壤,中国现有的法律解释体制具备实行司法能动主义的制度条件。目前,中国社会转型的现实国情也必然要求地方法院积极进行司法创新,探索能动主义的地方司法模式。因此,选择何种司法方式应从具体的实践逻辑出发探讨其功能正当性,而非从某个概念或理论出发探讨其逻辑应然性。

关键词：司法能动司法克制法律解释社会转型

Method of Blue-White Car Plate Locating

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Method of Blue-White Car Plate Locating

2010 Second IITA International Conference on Geoscience and Remote Sensing (IITA-GRS 2010)

作者： Xianmin Wei Computer and Communication Engineering school of Weifang university Weifang china

Car-plate locating is the first step of the recognition of car-plate,the accuracy of locating plays an important role in the next *** paper introduce some methods of car-plate ***,the input image is roughly segmented absed on the color information,and some regions with the color of car-plate are *** the false regions in the result image is *** last,projection method is used to get the accurate positon of the *** experimental result shows that the proposed method is very effective.

关键词： car-plate locating segmentation based on colorful image Blue-White Car Plate Locating

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行波超声波电动机性能分析及其优化设计

微特电机 2003年第5期31卷 13-15,19页

作者：赵向东陈波赵淳生山东科技大学泰安271019 南京航空航天大学南京210016

以行波型超声波电动机为研究对象 ,开发了超声波电动机性能仿真分析软件。利用该软件可预测出处于设计阶段的超声波电动机的输出特性曲线及各项动力学特性指标 ,还能对定子尺寸、压电陶瓷厚度、模态阶次、预压力等等对超声波电动机性能... 详细信息

以行波型超声波电动机为研究对象 ,开发了超声波电动机性能仿真分析软件。利用该软件可预测出处于设计阶段的超声波电动机的输出特性曲线及各项动力学特性指标 ,还能对定子尺寸、压电陶瓷厚度、模态阶次、预压力等等对超声波电动机性能有显著影响的参数作变参数分析。以此为依据 ,提出了超声波电动机优化设计的原则 ,阐述了超声波电动机优化设计的实现过程 ,特别对工作模态的选择和预压力及输出特性的选定进行了详细分析。

关键词：行波超声波电动机性能分析优化设计动力特性仿真分析软件动力学特性指标

IEEE802.11无线局域网的一种新的加密机制

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山东大学学报（工学版） 2003年第2期33卷 158-162页

作者：赵方明田芳林洪涛山东大学信息科学与工程学院山东济南250100 齐鲁电机制造有限公司山东济南250100

IEEE802.11无线局域网的加密采用RC4加密算法,RC4算法本质上是一个伪随机数生成算法,本身有缺陷,本文在对IEEE802.11无线局域网的加密机制进行分析的基础上,引入了一种新的伪随机数生成方法———Fastpacketkeying,并提出了改进方案.

关键词：计算机网络无线电信号网络分析