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91.
针对嵌入式系统芯片SoC开发验证阶段的需求,介绍了一种通用的SoC软硬件协同仿真平台。软件仿真由C/C++和汇编语言编写,硬件仿真基于VMM验证方法学所搭建,SoC设计代码由RTL代码编写而成。将SoC设计代码中的ARM由DSM模型替代,通过VCS编译器将软硬件协同起来进行信息交互,实现一种速度快、真实性高、调试方便的...  相似文献   
92.
In coal powder flow transportation and combustion, powder mass flow rate is a key parameter to be monitored and controlled. Electrostatics is one of the techniques used for such task with its non-intrusive, robust, and low cost natures. The passive electrostatic meters measure charge induced on the detecting electrodes. As it is known that the induced signal is not only dependent on the solids mass flow rate, but also affected by solids velocity. However, the velocity of particles usually referred to is the axial velocity. In reality, the solids velocity is a vector, its projections in both the radial and tangential directions also need to be investigated. This paper analyses the dynamic sensitivity of ring-shaped electrostatic sensors using the finite element method (FEM), and investigates the influence of the axial and radial velocities on the induced signal on the electrodes.  相似文献   
93.
This paper studies the problem of stabilizing a linear system with delayed and saturating feedback. It is known that the eigenstructure assignment‐based low‐gain feedback law (globally) stabilizes a linear system in the presence of arbitrarily large delay in its input, and semi‐globally stabilizes it when the input is also subject to saturation, as long as all its open‐loop poles are located in the closed left‐half plane. Based on a recently developed parametric Lyapunov equation‐based low‐gain feedback design method, this paper presents alternative, but simpler and more elegant, feedback laws that solve these problems. The advantages of this new approach include its simplicity, the capability of giving explicit conditions to guarantee the stability of the closed‐loop system, and the ease in scheduling the low‐gain parameter on line to achieve global stabilization in the presence of actuator saturation. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
94.
This article examines two manufacturing lines producing semiconductors using different technology concepts, namely Conventional Line (CL) and Lean Production Line (LPL). Both lines manufacturing the same products were compared using various factors, including working conditions, task risks and dangers of the job, and physical body stress. Ergonomic approaches were adopted in the investigation of the two lines. Survey questionnaires were administered to 30% of the workers, and multiple statistical tests were used to determine crucial predictors and to investigate the interactions between the factors. This research has shown that improved ergonomics factors will lead to better working conditions and thus increased job satisfaction. The observed ergonomic differences of these two production lines are compared, and appropriate managerial remedial action is recommended. The interventions to both the lines should reduce accident rates, minimize waste of resources, improve work effectiveness, and provide a better working environment that enhances employees' morale and maximizes productivity and profits. © 2010 Wiley Periodicals, Inc.  相似文献   
95.
Partner selection is a major issue in the formation of a virtual enterprise. In practice, in the partner selection process, the information about the candidates and their performances are incomplete and uncertain. Vague sets theory is one of the methods used to deal with uncertain information. In this paper, a new method based on vague sets is proposed to deal with the partner selection problem in the formation of a virtual enterprise while the factors of satisfaction degree, due date, cost and the precedence of tasks are taken into account. On the basis of the agreement index of satisfaction degree, the formulated partner selection problems are interpreted so as to maximize the minimum agreement index. To solve the problem, an improved particle swarm optimization (PSO) algorithm is proposed. Finally, the simulation of a numerical example demonstrates that the method is effective.  相似文献   
96.
This paper is devoted to investigating inventory control problems under nonstationary and uncertain demand. A belief-rule-based inventory control (BRB-IC) method is developed, which can be applied in situations where demand and demand-forecast-error (DFE) do not follow certain stochastic distribution and forecasting demand is given in single-point or interval styles. The method can assist decision-making through a belief-rule structure that can be constructed, initialized and adjusted using both manager’s knowledge and operational data. An extended optimal base stock (EOBS) policy is proved for initializing the belief-rule-base (BRB), and a BRB-IC inference approach with interval inputs is proposed. A numerical example and a case study are examined to demonstrate potential applications of the BRB-IC method. These studies show that the belief-rule-based expert system is flexible and valid for inventory control. The case study also shows that the BRB-IC method can compensate DFE by training BRB using historical demand data for generating reliable ordering policy.  相似文献   
97.
动态相位调整技术在FPGA中的设计与实现   总被引:1,自引:0,他引:1  
提出一种基于FPGA的动态相位调整实现方案。在高速数据传输接口中,由于数据窗缩小以及传输路径不一致,造成数据和时钟信号在FPGA的接收端发生位偏移和字偏移。动态相位调整技术根据当前各数据线物理状态,对各信号线动态进行去偏移操作,克服了静态相位调整中参数不可再调的缺点,使接口不断适应外部环境的变化,从而保证数据的可靠传输。  相似文献   
98.
基于频繁项挖掘的未知P2P流量识别方法   总被引:1,自引:0,他引:1  
提出一种基于多维聚类的频繁项挖掘算法,利用聚类思想自动挖掘网络中的显著流量及其规则,并在此基础上,对显著流量进行P2P疑似性判别,同时结合应用层特征识别技术,对高度疑似的P2P显著流量类进行过滤,实现未知P2P流量检测。实验结果表明,该方法是有效的。  相似文献   
99.
基于Python的实时嵌入式软件测试脚本   总被引:3,自引:0,他引:3       下载免费PDF全文
蒋崇武  刘斌  王轶辰  胡璇 《计算机工程》2009,35(15):64-66,7
基于Python语言设计一种实时测试脚本,开发扩展模块,实现测试脚本与嵌入式软件仿真测试环境(ESSTE)的接口。该测试脚本使用简便,实时性高、描述能力强、具有良好的可复用性,目前已成功应用到ESSTE中。对多个实时嵌入式软件进行测试,结果验证了该测试脚本的正确性和实时性。  相似文献   
100.
基于GIS和神经网络的泥石流危险性评价系统   总被引:3,自引:0,他引:3       下载免费PDF全文
基于ArcEngine组件和.Net集成开发天山公路泥石流危险性评价系统,将GIS技术和神经网络集成应用于泥石流危险性评价中,发挥GIS强大的空间信息可视化管理和分析功能以及神经网络的非线性描述和分析功能,实现泥石流危险性评价的可视化管理,为工程决策者和管理人员提供一种强有力的决策支持方案。  相似文献   
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