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2011 International Conference on Computer science and Information technology(ICCSIT 2011)

作者： Litian Xiao Mengyuan Li Ming Gu Jiaguang Sun National Laboratory for Information Science and Technology Key Laboratory for Information System Security Ministry of EducationDepartment of Computer Science and Technology School of Software Tsinghua University Beijing Special Engineering Design and Research Institute National Laboratory for Information Science and Technology Key Laboratory for Information System Security Ministry of Education Department of Computer Science and Technology School of Software Tsinghua University

COQ is an interactive theorem proving tool. The paper abstractly describes the feature of COQ, the architecture and working modes of PLC program with the example of typical PLC. It also introduces the first-order logic syntax and semantics of Intuitionistic Logic. It briefly introduces the main Gallina language syntax elements, the corresponding use methods and main theorem proving tactic on COQ. The work has modeled kernel data type and basic statements and and the denotational semantics of PLC program with Gallina. It has given the correctness proof of PLC program based on theorem proving, i.e. based on semantics function the relationship of configuration between the before codes execution and the after is proved. The main purpose is to prove whether a PLC program satisfies certain nature within a scan period.

关键词： PLC Program, Embedded system, Verification, Denotational Semantics, Theorem Proving, COQ

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A MISO cooperative transmission algorithm for clustering wireless sensor network

A MISO cooperative transmission algorithm for clustering wir...

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International Conference on Electronics, Communications and Control (ICECC)

作者： Guoqiang Zheng Tingting Wei Jishun Li Electronic Information Engineering College Henan University of Science and Technology Luoyang China Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang China

A MISO cooperative transmission algorithm for clustering wireless sensor network is proposed in this paper. In this algorithm, we choose cooperative nodes according to cooperative threshold, and optimize nodes' transmission power with finite-rate feedback. Then we analyze the implementation process in detail, derive the method of optimizing parameters. In the end verify this algorithm at simulation platform. The result shows that, this MISO cooperative transmission algorithm for clustering wireless sensor network can reduce transmission power of transmitting nodes effectively. So this algorithm can reduce the energy consumption, and also extend the life cycle of the whole wireless sensor network certainly.

关键词： Clustering algorithms Wireless sensor networks Channel state information Vectors Energy consumption MIMO Array signal processing

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On Energy-Efficient Trap Coverage in Wireless Sensor Networks

On Energy-Efficient Trap Coverage in Wireless Sensor Network...

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Real-Time systems Symposium (RTSS)

作者： Junkun Li Jiming Chen Shibo He Tian He Yu Gu Youxian Sun State Key Laboratory of Industrial Control Technology Zhejiang University China Computer Science and Engineering University of Minnesota USA Pillar of Information System Technology and Design Singapore University of Technology and Design Singapore

In wireless sensor networks (WSNs), trap coverage has recently been proposed to tradeoff between the availability of sensor nodes and sensing performance. It offers an efficient framework to tackle the challenge of limited resources in large scale sensor networks. Currently, existing works only studied the theoretical foundation of how to decide the deployment density of sensors to ensure the desired degree of trap coverage. However, the practical issues such as how to efficiently schedule sensor node to guarantee trap coverage under an arbitrary deployment is still left untouched. In this paper, we formally formulate the Minimum Weight Trap Cover Problem and prove it is an NP-hard problem. To solve the problem, we introduce a bounded approximation algorithm, called Trap Cover Optimization (TCO) to schedule the activation of sensors while satisfying specified trap coverage requirement. The performance of Minimum Weight Trap Coverage we find is proved to be at most O(ρ) times of the optimal solution, where ρ is the density of sensor nodes in the region. To evaluate our design, we perform extensive simulations to demonstrate the effectiveness of our proposed algorithm and show that our algorithm achieves at least 14% better energy efficiency than the state-of-the-art solution.

关键词： Sensors Wireless sensor networks Approximation algorithms Algorithm design and analysis Approximation methods Euclidean distance Optimization

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Nonlinear dynamic analysis of LOCA based on Secondary development of ANSYS

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Hedongli Gongcheng/Nuclear Power Engineering 2011年第SUPPL. 1期32卷 98-102页

作者： Qi, Huan-Huan Zeng, Zhong-Xiu Zhang, Yi-Xiong Liu, Wen-Jin Wang, Wei Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu 610041 China

In this paper, nonlinear dynamic response under loss of coolant accident (LOCA) transient in the nuclear reactor coolant system (RCS) is investigated with ANSYS program. Many nonlinear factors, such as different structural stiffness in tension and compression, gap and plastic strain caused by main pipes' break etc. are considered. The Secondary development of ANSYS is performed to form the customized module for implementing effective parameterized and modular modeling and LOCA nonlinear analysis. Comparison of the results calculated by ANSYS and program-specific shows that the results are generally consistent, but there are some differences locally. According to the experience of transient dynamic analysis, and there are so many non-linear factors in the reactor coolant system, the difference is acceptable. The efficiency of this engineering analysis is improved remarkably with the convenience of input and modeling, viewable layout and automatic creating of reports, when using the customized module based on ANSYS.

关键词： Loss of coolant accidents

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Model design of new product management information system based on BPR

Model design of new product management information system ba...

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International Conference on system science, Engineering design and Manufacturing Informatization (ICSEM)

作者： Xianzhao Jia Dong Fei Liu Hongbin School of Electrical Engineering Henan University of Science and Technology Luoyang 471003 China Henan Key Laboratory of Modem Mechanical Design and Transmission System Luoyang China School of Electrical Engineering Henan University of Science and Technology Luoyang China

Based on BPR theory, the new product development and manufacturing process status of a discrete manufacturing enterprise was analysed with finding out its existing problems, then a new reasonable process was designed and the model of management information system was established. Through the analysis of this case, this paper provides a reference for other similar enterprises to manage new product development and promote the development of enterprise information.

关键词： Schedules Finance Business process re-engineering Bills of materials

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An Optimal Color Mapping Strategy Based on Energy Minimization for Time-Varying Data

An Optimal Color Mapping Strategy Based on Energy Minimizati...

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IEEE International Conference on Computer-Aided design and Computer Graphics

作者： Yi Peng Jie Dong Li Chen Haiyang Chu Junhai Yong Key Laboratory for Information System Security Ministry of Education Beijing China Department of Computer Science and Technology Tsinghua University Beijing China Tsinghua National Laboratory for Information Science and Technology Beijing China School of Software Tsinghua University Beijing China

Color mapping plays a critical role in visualization of time-varying data and also sets a challenge for researchers due to the consistency of mapping and great changes in time-varying data. In order to solve this problem and generate feature-prominent animation, we present a two phase optimization technique using bilateral filtering and global energy functions. In the first phase, for each time step, we use a weighted mapping function which combines linear mapping and feature histogram. In the second phase, an optimization function taking global color mapping and minimum color difference into consideration is designed. So users can clearly distinguish between data in variable time steps and easily understand the corresponding relationships between different structures. The experiments' results show that our method can achieve high quality visualization for both static and time-varying data.

关键词： Image color analysis Data visualization Optimization Correlation Minimization Transfer functions Histograms

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Automatic Generation of Canonical Views for CAD Models

Automatic Generation of Canonical Views for CAD Models

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IEEE International Conference on Computer-Aided design and Computer Graphics

作者： Kaimo Hu Bin Wang Bin Yuan Junhai Yong Key Laboratory for Information System Security Ministry of Education Beijing China Department of Computer Science and Technology Tsinghua University Beijing China School of Software Tsinghua University Beijing China Tsinghua National Laboratory for Information Science and Technology Beijing China

Selecting the best views for 3D objects is useful for many applications. However, with the existing methods applied in CAD models, the results neither exhibit the 3D structures of the models fairly nor conform to human's browsing habits. In this paper, we present a robust method to generate the canonical views of CAD models, and the above problem is solved by considering the geometry and visual salient features simultaneously. We first demonstrate that for a CAD model, the three coordinate axes can be approximately determined by the scaled normals of its faces, such that the pose can be robustly normalized. A graph-based algorithm is also designed to accelerate the searching process. Then, a convex hull based method is applied to infer the upright orientation. Finally, four isometric views are selected as candidates, and the one whose depth image owns the most visual features is selected. Experiments on the Engineering Shape Benchmark (ESB) show that the views generated by our method are pleasant, informative and representative. We also apply our method in the calculation of model rectilinearity, and the results demonstrate its high performance.

关键词： Solid modeling design automation Mathematical model Visualization Three dimensional displays Equations Computational modeling

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An Example-Driven Symbol Recognition Approach Based on key Features in Engineering Drawings

An Example-Driven Symbol Recognition Approach Based on Key F...

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IEEE International Conference on Computer-Aided design and Computer Graphics

作者： Tiantian Guo Hui Zhang Yamei Wen Key Laboratory for Information System Security Ministry of Education Beijing China School of Software Tsinghua University Beijing China Tsinghua National Laboratory for Information Science and Technology Beijing China

In this paper, we present an example-driven symbol recognition algorithm based on its key features in CAD engineering drawings. When user provides an example of a specific symbol, the input symbol is analyzed and its features are extracted automatically. Based on the relation representation, the constrained tree with key feature priority can be established for this type of symbol. By this means, the symbol library can be built and expanded automatically in order to handle variety engineering drawings. In the next stage of the recognition processes, we first locate the key feature nodes in drawings, and then find other elements around which satisfy the topology structure of constrained tree. If all the elements and constrains in the tree are found, the symbol object will be recognized. Because of the accurate position, unnecessary matching calculations are greatly reduced. Experimental results validate that our approach is effective.

关键词： Engineering drawings Feature extraction design automation Pattern recognition Knowledge acquisition Libraries

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Torus/torus intersection

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Computer-Aided design and Applications 2011年第3期8卷 465-477页

作者： Liu, Xiao-Ming Liu, Chang-Yuan Yong, Jun-Hai Paul, Jean-Claude Tsinghua University Beijing China Command and Engineering College of Chemical Defense Beijing China Key Laboratory for Information System Security Ministry of Education Beijing China Tsinghua National Laboratory for Information Science and Technology Beijing China INRIA France

This paper presents a new algorithm for torus/torus intersection. The pre-image of the intersection in the parametric space of one torus is represented by an implicit equation. The pre-image is divided into one-valued function curve segments by characteristic points. The topological feature of these characteristic points is analyzed to obtain the structure of the pre-image. Intersection curves satisfying required precision are found by a self-adaptive refinement method. Experiment results are presented to illustrate the stability and efficiency of the method. © 2011 CAD Solutions, LLC.

关键词： Topology

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Radar equation of high-speed weak target

Radar equation of high-speed weak target

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International Conference on Advanced Mechatronic systems (ICAMechS)

作者： Cun-suo Pang Nan Zhang Xiang-yang Lu National Key Laboratory for Electronic Measurement Technology Key Laboratory of Instrumentation Science and Dynamic Measurement of Ministry of Education North University of China Taiyuan China Second System Design Department of the Second Research Academy of CASIC Beijing China Electrical Engineering Department Electrical Engineering Department Zhengzhou China

Without considering the echo signal power changes caused by target distance changes during the accumulated time the traditional radar equation is hardly applied. We take account of the effects of velocity, signal-to-noise ratio during the processing time; a modified radar equation is built which can be used for long-time integration of weak targets with high speed. After analyzing the relation between detection range and target velocity, integration time with processing time, we draw the constraint conditions and the corresponding conclusions.

关键词： Radar Laboratories Silicon compounds Equations Instruments Power measurement Velocity measurement

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