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1.
时变网络中国邮路问题的时间自动机模型   总被引:1,自引:0,他引:1  
基于时间自动机理论,提出了时间窗、时间依赖服务代价以及时间依赖旅行时间这3类时变网络中国邮路问题的统一建模的语义模型和求解方法.首先,将中国邮路问题可行解条件和时变参数与时间自动机联系起来,建立了3类问题的统一时间自动机系统(timed automata system,简称TAS)模型;然后,将时变网络中国邮路问题归结为TAS模型上的一系列可达性判定问题,并利用形式化验证算法给出了有效的求解方法.由于TAS模型中存在O(|A|+|AR|+1)个时间自动机,限制了问题求解规模.为此,通过扩展时间自动机语义,提出了TAS模型中的时间自动机合并策略,进而将TAS模型转换为一个广义时间自动机(GTA)模型.基于GTA模型,利用UPPAAL工具对9组、共54个随机算例进行实验.实验结果表明,该方法在求解精度上明显优于运筹学领域的方法.  相似文献   

2.
本文所设计的DSP最小系统由TI公司的定点DSP芯片TMS320VC5402及其相关电源和时钟电路、片外扩展存储器、A/D、D/A、标准UART接口构成。以DSP工作原理为基础,对最小系统板进行软硬件设计。同时,实现了基于DSP最小系统的FIR滤波器算法。  相似文献   

3.
针对UC/OSⅡ在DSP2407A上的移植,着重分析和解决了UC/OSⅡ在DSP2407A移植中堆栈保存与恢复及任务切换等问题。  相似文献   

4.
张旭  韩其睿 《微计算机信息》2006,22(34):115-116
本论文介绍了基于TMS320F2812DSP的数据采集系统的整体结构和各组成模块。介绍了主要芯片的性能和工作原理,A/D转换芯片前端电路设计,A/D转换芯片和DSP数字信号处理器的硬件接口设计,DSP数字信号处理器与PC机的串行通信方案设计,以及DSP数字信号处理器的存储器扩展,最后给出该系统的软件架构和优化设计。  相似文献   

5.
设计了一种可同时测试多个参数,功能综合的风力发电机测试系统。分析了两种A/D芯片与DSP的连接电路,在系统前端对待测的高电压与高电流进行信号调理,实现A/D芯片与DSP芯片之间并行的连接方式。利用DSP定时器中断来触发A/D芯片进行数据采集,同时利用CPLD控制A/D芯片同步采样。采用内部软件滤波,要求滤除干扰的奇次谐波,实验结果证明滤波效果明显。  相似文献   

6.
基于DSP和CPLD的无位置传感器无刷直流电动机控制系统   总被引:4,自引:0,他引:4  
周兰 《自动化信息》2010,(6):46-47,22
本文提出了一种基于DSP+CPLD的无位置传感器的无刷直流电动机控制系统,该系统以DSP控制器TMS320LF2407A为控制核心。它研究了转子位置的检测,同时,进行了该控制系统的控制策略分析和硬件电路及应用软件设计。采用专家智能系统以实现换向控制,使用外部参考电压提高DSP的A/D转换精度。该系统大大简化了硬件结构,使电机控制更加稳定。  相似文献   

7.
李明  程明霄  朱宇翔 《微处理机》2007,28(3):117-119
介绍了新型DSP——LF2407A的特性和时钟芯片DS17887的工作原理,并介绍了基于LF2407A控制DS17887进行时钟读写的软硬件设计方案。该方案发挥了DSP的优势,解决了测控系统对时间数据的需求问题。  相似文献   

8.
伺服控制系统的DM9000A以太网接口设计   总被引:2,自引:0,他引:2  
采用以太网控制器DM9000A,实现DSP+FPGA伺服控制系统的100M以太网接入.介绍了DM9000A的功能原理,给出了该器件与TMS320F2812 DSP的硬件连接方法、软件初始化及数据收发控制流程.  相似文献   

9.
基于DSP+CPLD的数据采集系统研究   总被引:2,自引:0,他引:2  
为了节约成本和提高DSP的利用率,提出了一种基于DSP+CPLD的数据采集系统的设计方案。该系统以TMS320F2812为DSP核心处理器,结合CPLD器件EPM3256进行逻辑设计,实现了DSP与A/D器件的高速并行工作。实例应用表明,该系统充分发挥了DSP的信号处理能力及CPLD编程简单的优势,提高了系统的性价比,具有一定的实用性。  相似文献   

10.
介绍一种基于DSP的黑白电视信号采集电路。电路由通用视频A/D转换器构成,DSP启动A/D转换并读取A/D转换结果。电路结构简洁、成本低、容易实现,能满足黑白电视信号采集的需要。  相似文献   

11.
A method of transient adaptive sub-cells (TAS) suitable for unstructured grids that is modified from the existing one for the structured grids of DSMC is introduced. The TAS algorithm is implemented within the framework of a parallelized DSMC code (PDSC). Benchmarking tests are conducted for steady driven cavity flow, steady hypersonic flow over a two-dimensional cylinder, steady hypersonic flow over a cylinder/flare and the unsteady vortex shedding behind a two-dimensional cylinder. The use of TAS enables a reduction in the computational expense of the simulation since larger sampling cells and less simulation particles can be employed. Furthermore, the collision quality of the simulation is maintained or improved and the preservation of property gradients and vorticity at the scale of the sub-cells enables correct unsteady vortex shedding frequencies to be predicted. The use of TAS in a parallel-DSMC code allows simulations of unsteady processes at a level to be carried out efficiently, accurately and with acceptable computational time.  相似文献   

12.
The technology acceptance scale (TAS) by van der Laan, Heino, and De Waard (1997) measures the psychological construct of the same term as a sum of attitudes of an operator toward a specific complex sociotechnical system. The TAS has been claimed to comprise two subscales, usefulness and satisfaction. However, recent empirical work has found evidence for only one underlying factor. To provide further insight into the factor structure of the TAS, this study adopts a Bayesian exploratory factor analysis (BEFA) to analyse the data of a flight simulation study regarding single pilot operations. A series of Markov chain Monte Carlo (MCMC) models is used to assess the latent factor structure of the TAS for the two different crewing conditions and their corresponding workstation and cockpit setups of the copilot. A reliable step-by-step data analysis of the MCMC models provides evidence for a one-factor solution of the scale. The divergence to the previous studies which claim two factors can be due to the different applications as well as due to different statistical paradigms and methodological issues in exploratory factor analysis.  相似文献   

13.
针对港口货车对位存在的实际问题,我们开发出了基于光电技术和PLC的拖车对位系统。本文主要介绍了拖车对位系统的原理和功能的实现,通过在现场的运行实践表明该系统能显著提高港口的工作效率。  相似文献   

14.
The present study evaluated the reliability and validity of the Triage Assessment Survey: Organizations (TAS:O), a 27-item, 5-point, Likert summated rating scale. One hundred and seventeen participants responded to the TAS:O after reading mild, moderate, marked and severe organizational crisis scenarios. The overall Cronbach's alpha and split-half reliability were both .93. Confirmatory factor analysis revealed three factors, supporting the hypothesis that the TAS:O is comprised of three distinct factors (i.e., Affect, Behavior, and Cognition). An analysis of variance provided evidence that the TAS:O has the capacity to distinguish among mild, moderate, marked, and severe crises. Because this research is the first to evaluate the TAS:O, further studies are needed to strengthen confidence in the psychometric properties of this scale.  相似文献   

15.
Reports the completion of four fundamental fluidic operations considered essential to build digital microfluidic circuits, which can be used for lab-on-a-chip or micro total analysis system (/spl mu/TAS): 1) creating, 2) transporting, 3) cutting, and 4) merging liquid droplets, all by electrowetting, i.e., controlling the wetting property of the surface through electric potential. The surface used in this report is, more specifically, an electrode covered with dielectrics, hence, called electrowetting-on-dielectric (EWOD). All the fluidic movement is confined between two plates, which we call parallel-plate channel, rather than through closed channels or on open surfaces. While transporting and merging droplets are easily verified, we discover that there exists a design criterion for a given set of materials beyond which the droplet simply cannot be cut by EWOD mechanism. The condition for successful cutting is theoretically analyzed by examining the channel gap, the droplet size and the degree of contact angle change by electrowetting on dielectric (EWOD). A series of experiments is run and verifies the criterion.  相似文献   

16.
孟星  胡怡红  寿国础 《测控技术》2020,39(10):93-96
时间敏感网络(TSN)是支持工业互联网的以太网新标准。TSN通过引入时间感知整形器(TAS)来精确控制不同优先级别的数据帧转发,使以太网能够支持低时延、低时间抖动的确定性服务。对TSN的目的、发展现状以及主要标准进行了叙述,结合TAS的基本原理和工作流程,提出了TAS的测试方案,将其划分为几个独立的部分,采用观察测试流量通过每个部分后特征变化的测试方法,并完成了测试设计和测试验证,测试结果证明了测试方案的有效性。  相似文献   

17.
Research suggests that human limitations are rarely considered in the design of knowledge-based authentication systems. In an attempt to foster entry to a system, individuals tend to choose passwords which are easy to recall. However, inappropriate selection can compromise data security. A novel approach has been developed to restore the balance between security and memorability through the use of the haptic channel. This paper introduces the Tactile Authentication System (TAS), which enables the user to authenticate entry through the ability to remember a sequence of pre-selected tactile sensations. The design process undertaken to develop distinguishable tactile stimuli for use within TAS is described, and details of the recognition-based tactile authentication mechanism are also presented. Findings from an empirical study reported in this paper, have revealed that 16 participants were able to authenticate access to TAS over the course of a one-month period, with low levels of error. The approach was found to offer benefits over conventional visual-based authentication methods. Tactile stimuli are presented underneath the fingertips, and are therefore occluded from others. As the sense of touch is personal to each user, tactile stimuli are difficult to describe in concrete terms, and cannot easily be written down or disclosed, thereby reducing the chance of unauthorized third party access.  相似文献   

18.
针对科技服务业的人才特征,以心理学、生理学和社会学作为理论基础.设计和实现面向科技服务业的人才测评系统,完整地实现整个测评业务流程,并具有在线测试管理.实时监控和反馈,文件和报告自动生成等功能特点,为高新技术企业招聘人才提供一个科学和高效的方式。  相似文献   

19.
针对科技服务业的人才特征,以心理学、生理学和社会学作为理论基础,设计和实现面向科技服务业的人才测评系统,完整地实现整个测评业务流程,并具有在线测试管理,实时监控和反馈,文件和报告自动生成等功能特点,为高新技术企业招聘人才提供一个科学和高效的方式。  相似文献   

20.
本文介绍了采用Ar+H_2混合气体保护自动点焊(TAS焊)新工艺,实现了压力传感器、电感传感器等器件的封装。文中对传感器结构及焊接特点,TAS焊接设备及工艺作了详细的阐述。  相似文献   

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