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推进技术 1994年第1期15卷 32-38,57页

作者：方蜀州胡克娴北京理工大学飞行器工程系

对已有的几种三维药柱燃面推移模型进行了分析比较，提出了一种新方法──三维实体造型法，并进行了翼柱形装药的工作过程仿真计算。证明该方法具有通用性强、使用方便、输出信息完备、计算精度高等特点，适合在工程设计中推广应用。

关键词： CAD 模拟固体推进剂火箭发动机

Cell cycle-dependent gene networks relevant to cancer

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Progress in Natural Science:Materials International 2008年第8期18卷 945-952页

作者： Yun Xiao a,1, Xia Lia,b,*,1, Yueying Yang a, Yadong Wangc, Shaoqi Rao a,b a College of Bioinformatics Science and technology, and Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State, Harbin Medical University, Harbin 150086, china b Biomedical Engineering institute of Capital Medical University, beijing 10004, china c Department of computer Science, Harbin institute of technology, Harbin 150080, china College of Bioinformatics Science and technology and Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State Harbin Medical University Harbin 150086 China Biomedical Engineering institute of Capital Medical University Beijing 10004 China Department of computer Science Harbin Institute of Technology Harbin 150080 China

The analysis of sophisticated interplays between cell cycle-dependent genes in a disease condition is one of the largely unexplored areas in modern tumor biology research. Many cell cycle-dependent genes are either oncogenes or suppressor genes, or are closely associated with the transition of a cell cycle. However, it is unclear how the complicated relationships between these cell cycle-dependent genes are, especially in cancers. Here, we sought to identify significant expression relationships between cell cycle-dependent genes by analyzing a HeLa microarray dataset using a local alignment algorithm and constructed a gene transcriptional network specific to the cancer by assembling these newly identified gene-gene relationships. We further characterized this global network by partitioning the whole network into several cell cycle phase-specific sub-networks. All generated networks exhibited the power-law node-degree distribution, and the average clustering coefficients of these networks were remarkably higher than those of pure scale-free networks, indicating a property of hierarchical modularity. Based on the known protein-protein interactions and Gene Ontology annotation data, the proteins encoded by cell cycle-dependent interacting genes tended to share the same biological functions or to be involved in the same biological processes, rather than interacting by physical means. Finally, we identified the hub genes related to cancer based on the topological importance that maintain the basic structure of cell cycle-dependent gene networks.

关键词： Cell cycle Microarray HeLa cell Gene network

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电传动履带车辆驱动系统建模与转向特性研究

系统仿真学报 2006年第10期18卷 2815-2818页

作者：陈树勇孙逢春北京理工大学机械与车辆工程学院北京理工大学机械与车辆工程学院北京100081

为准确分析某电传动履带车辆转向特性,运用现代设计理论与方法—协同仿真与虚拟样机技术,借助动力学分析软件RecurDyn/Track-HM和控制系统分析软件Matlab/Simulink仿真平台,建立了整车行动部分三维多体动力学模型和控制系统模型。以不... 详细信息

为准确分析某电传动履带车辆转向特性,运用现代设计理论与方法—协同仿真与虚拟样机技术,借助动力学分析软件RecurDyn/Track-HM和控制系统分析软件Matlab/Simulink仿真平台,建立了整车行动部分三维多体动力学模型和控制系统模型。以不同车速v、不同转向半径R下的转向特性为例,对其进行了理论分析与协同仿真分析,并通过与理论计算和试验结果对比验证了模型的正确性。该方法对深入了解整车的转向特性以及试验调试策略具有重要指导意义,可进一步缩短研制周期,降低研究成本,同时为履带车辆电驱动系统动态特性的深入研究提供了一条新的思路。

关键词：电传动履带车辆协同仿真转向特性 RecurDyn

Modeling　and　Analysis　of　Capacitated　Transfer　Lines　with　Unreliable　Machines　and　Deterministic　Procesing　Times

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Systems Science and Systems Engineering 1997年第1期7卷 53-60页

作者： SHU Songgui JIANG Changjun institute of Automation, Academia Sinica beijing, 100080, china institute of Shandong Mining technology, Taian, 271019, china

This paper presents an efficient method of equivalient workstations for modeling and analysis of multistage transfer lines with unreliable machines and finites buffers. The deterministic processing times for discrete parts and random failuse and repair times for machines are assumed. These buffers lead to blockage and starvation in operation due to limited storage capacities and make the problem of modelling and analysis very difficult to treat because they have large state spaces and cannot be decomposed exactly. A single buffer between two reliable workstations is analysed first. Then an equivalent workstation without starvation and blockage is constructed. Thereafter connecting all the equivalent workstations in series we get the equivalent transfer line. A set of preformance measures such as the production rates, efficiencies and average inventory levels are derived in explicit analytical expressions. Finally two numerical examples are given for comparing these calculated results with those of S. B. Gershwin (1987) and C. R. Glasseye & Y. Hong (1993) and illustrating the application of the method in engineering design directly.

关键词： Intelligent manufacturing system (IMS) computer integrated manufacturing System (CIMS) Inventory levels and throughput in transfer lines Reliability of transfer lines.

Experimental Study of Monitoring and Controlling of Composite Cure Process in Autoclave Featured with Fiber Optic Sensor

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Journal of Materials Science & technology 2001年第4期17卷 449-452页

作者： Boming ZHANG, Zhanjun WU , Dianfu WANG and Shanyi DU center for composite, Harbin institute of technology Harbin 150001, china Harbin Inst Technol Ctr Composite Harbin 150001 Peoples R China

With the aid of the latest fiber optic sensing technology parameters in the cure process of ther- mosetting resin-matrix composite, such as temperature, viscosity,void and residual stress, can be monitored entirely and *** this paper, experiment results of viscosity measurement in composite cure process in autoclave using fiber optic sensors are presented. Based on the sensed information, a computer program is utilized to control the cure process. With this technology, the cure process becomes more apparent and controllable, which will greatly improve the cured products and reduce the cost.

关键词： Experimental Study of Monitoring and Controlling of Composite Cure Process in Autoclave Featured with Fiber Optic Sensor

A new simulated annealing method of designing NMR biplanar shim coils

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Progress in Natural Science:Materials International 2006年第7期16卷 747-752页

作者： QI Feng, TANG Xin, WANG Weimin, SHEN Yifei, LIU Shaopo and JIANG Zhongde ( Key Laboratory for Quantum Information and Measurements of Ministry of Education, School of Electronics Engineering & computer Science, Peking University, beijing 100871, china institute of Heavy Ion Physics, and beijing Key Laboratory of Medical Physics and Engineering, Physical School, Peking University, beijing 100871, china) [a]Key Laboratory for Quantum Information and measurements of ministry of Education School of Electronics Engineering & Computer Science Peking University Beijing China [b]institute of Heavy Ion Physics and Beijing Key laboratory of Medical Physics and Engineering Physical School Peking University Beijing China

A new SA (simulated annealing) method is presented for the design of longitudinal shim coils for NMR (nuclear magnetic resonance) equipment. First, AGL (adaptive Gauss-Lobatto) quadrature used by the traditional SA method is analyzed. Two kinds of complete elliptic integrals are introduced to integrate the spatial magnetic field, which increases the computing speed by 13. 3 times. Then, the system energy calculation is extended to the field of the z-axis. The results illustrate that the coil-set efficiency designed by the new SA method is 15 % higher than that of the traditional one, and the field inhomogeneity is reduced from 1.20 % to 0.49 % . Finally, a prototype of coil assembly for NMR rock-core analyzer is built, and the experimental results are in good agreement with the theoretically calculated results.

关键词： NMR shim coil design simulated-annealing method complete elliptic integral.

Design of an MRI quadrature-data acquisition card

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Progress in Natural Science:Materials International 2006年第3期16卷 255-259页

作者： JIANG Zhongde, ZU Donglin and GU Xiaofang (institute of Heavy Ion Physics, beijing Key Laboratory of Medical Physics & Engineering, School of Physics, Peking University,beijing 100871, china) [a]institute of Heavy Ion Physics Beijing Key Laboratory of Medical Physics & Engineering School of Physics Peking University Beijing China

A design of a quadrature-data acquisition card based on peripheral component interconnect (PCI) bus for mini-type magnetic resonance imaging (MRI) system is reported. It uses two high speed analog-to-digital converters (ADCs) to sample the MRI signals and two static random access memories (SRAMs) to store the data which will be read to the computer by PCI bus after sampling. All the logic control signals on the card are generated by the field programmable gate array (FPGA). The software Foundation3.1 is used to design the FPGA and achieve useful result after simulating and implementing. The card has some merits that normal commercial cards do not have. For example, the sampling parameters can be varied according to different pulse sequences.

关键词： MRI data acquisition FPGA PCI bus.

THE STABILITY OF THE θ-METHODS FOR DELAYDIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 1999年第4期17卷 441-448页

作者： Jing-jun Zhao Ming-zhu Liu(Department of mathematics, Harbin institute of technology, Harbin 150001, china)Shen-shan Qiu(Department of computer Science and Engineering, Harbin institute of technology, Harbin 150001, china) 哈尔滨工业大学数学系黑龙江哈尔滨 150001 哈尔滨工业大学数学系黑龙江哈尔滨哈尔滨工业大学计算机系黑龙江哈尔滨

This paper deals with the stability analysis of numerical methods for the solution of delay differential equations. We focus on the behaviour of three θ-methodsin the solution of the linear test equation u'(t)-A(t)u(t)+B(t)u( (t)) with (t)and A(t),B(t) continuous matrix functions. The stability regions for the threeθ-methods are determined.

关键词： Delay differential equations Numerical solution Stabilityl θ-methods.

The DPGA for Conbining the Superscalar and Multithreaded Processors Principal

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High technology Letters 2001年第1期7卷 79-85页

作者： Abdelkadel Chaib, Hu Mingzeng (Department of computer Science and technology, Harbin institute of technology, Harbin 150001 P.R.china) Dept. of computer Sci. and Technol. Harbin Institute of Technology Harbin 150001 China

The performance of scalable shared-memory multiprocessors suffers from three types of latency; memory latency, the latency caused by inter-process synchronization ,and the latency caused by instructions that take multiple cycles to produce results To tolerate these three types of latencies, The following techniques was proposed to couple: coarse-grained multithreading, the superscalar processor and a reconfigurable device, namely the overlapping long latency operations of one thread of computation with the execution of other threads The superscalar processor principle is used to tolerate instruction latency by issuing several instructions simultaneously The DPGA is coupled with this processor in order to improve the context-switching

关键词： DPGA Context switching Functional and control conflicts Data dependencies WAW RAW WAR hazards Tomasolo’s algorithm