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91.
针对模拟电压监测的技术现状,提出以支持IEEE1149.1接口标准的模拟电压监测器进行电压监测电路设计;简要介绍了模拟电压监测器的基本结构、操作原理和应用方式;通过实际电压电路可测性设计方案的制定分析、实验和测试,说明了该电压监测器的优势和特点;同时,文中提出应用FPGA作为内建自测试(BIST)控制器执行监测操作,是边界扫描技术与BIST技术结合应用的一次创新;最后的应用结果表明,该监测器的使用为电路设计人员的可测性设计提供了一种新思路和参考方法.  相似文献   
92.
针对传统的网络故障诊断方法普遍具有自适应差、误报率高等的不足,提出了一种结合免疫算法和agent技术的网络故障诊断方法。在分布式环境中,按照网络的不同特征和环境差异,利用不同功能、不同类别的agent进行故障诊断,同时各agent之间能够互相协作,彼此进行信息交流,和采集数据,从而对所获得的故障类型进行诊断。实验证明,该方法能够对网络故障类型进行有效的判定,对以后大型网络故障诊断是一个很好的借鉴。  相似文献   
93.
A radio-frequency identification (RFID) system including hardware and software may be updated from time to time after first time deployment. To ensure the reliability of the system, extensive tests are required. However, enumerating all test cases is infeasible, especially when the tests involve time-consuming hardware operations. To solve this problem, we propose a testing methodology for RFID systems which does not enumerate all test cases but rather those which are representative. A clustering method is adopted in selecting representative test cases. Although a small number of selected test cases are run, we can still obtain a relatively high bug detection rate compared with running the enumerated test cases. Our extensive experiments show the efficiency and effectiveness of our testing methodology.  相似文献   
94.
图像的超分辨率是指利用一幅或者多幅的低分辨率图像,通过相应的算法来获得一幅对应的清晰的高分辨率图像.针对现有的基于学习的超分辨率方法低效率的问题,提出一种基于人工神经网络的快速超分辨率方法,该方法试图利用人工神经网络学习到高分辨率图像和低分辨率图像之间的函数关系,其理论基础来自于人工神经网络能够很好地求解流形学习中高维流形和低维流形之间的映射关系.  相似文献   
95.
In the literature, more and more clues show that the bidders indeed tend to risk averse. But as a good structure estimation procedure in first-price sealed-bid auctions, the traditional PPMLE (Piecewise Pseudo-Maximum Likelihood Estimation) approach is only applicable to the risk neutrality case. This study generalizes this approach to the risk aversion case, and obtains a simple estimation procedure for the Pareto family of private costs. In the procedure, the estimation order of distribution parameters of private costs is not important, which is different from the traditional PPMLE method. Though there is no unique estimator for θ 1 and γ, some guidance is given for real-world applications on the basis of our Monte Carlo simulation experiments. What’s more, this procedure can be reduced further, if one is only interested in estimating the private costs. Extensive simulation experimental results indicate that our approach outperforms or matches at least the traditional one in the case of risk neutrality, and is applicable to the risk aversion case.  相似文献   
96.
We propose a James-Stein-type shrinkage estimator for the parameter vector in a general linear model when it is suspected that some of the parameters may be restricted to a subspace. The James-Stein estimator is shown to demonstrate asymptotically superior risk performance relative to the conventional least squares estimator under quadratic loss. An extensive simulation study based on a multiple linear regression model and a logistic regression model further demonstrates the improved performance of this James-Stein estimator in finite samples. The application of this new estimator is illustrated using Ontario newborn infants data spanning four fiscal years.  相似文献   
97.
This technical note presents theoretical analysis and simulation results on the performance of a classic gradient neural network (GNN), which was designed originally for constant matrix inversion but is now exploited for time-varying matrix inversion. Compared to the constant matrix-inversion case, the gradient neural network inverting a time-varying matrix could only approximately approach its time-varying theoretical inverse, instead of converging exactly. In other words, the steady-state error between the GNN solution and the theoretical/exact inverse does not vanish to zero. In this technical note, the upper bound of such an error is estimated firstly. The global exponential convergence rate is then analyzed for such a Hopfield-type neural network when approaching the bound error. Computer-simulation results finally substantiate the performance analysis of this gradient neural network exploited to invert online time-varying matrices.  相似文献   
98.
The System Wide Information Management (SWIM) approach has been conceived to overcome the capacity and flexibility limitations of the current ATM systems. On the other hand the commercial applications of Unmanned Aerial Vehicles (UAVs) require the integration of these vehicles in the ATM. From this perspective, the unavoidable modernization of the ATM is seen as an opportunity to integrate the UAVs with the rest of the air traffic. This paper is devoted to study the feasibility and impact of the aggregation of UAVs on the future ATM supported by a SWIM inspired architecture. Departing from the existing technical documents that describe the fundamentals of SWIM we have explored the compatibility with a potential UAVs integration and also explored how the UAVs could help to improve the future ATM system. We will use the weather application as an example in both cases.  相似文献   
99.
Congestion on roads leads to uncertainty in travel times, which is important in delivery of goods, especially in a business environment where high levels of customer service are expected. Delivery periods to customers might be constrained by time windows, which makes the scheduling and routing of vehicles from the supplier’s side more difficult. Operations Research methods turn into heuristics for this type of application. But when, on top, uncertainty on travel times are the case, any hope of a simple and well-performing heuristic is lost. This study applies a methodology in which a heuristic is used to find a solution for scheduling and routing under deterministic travel times and, by means of simulation, though the use of Time Petri nets evaluates the sensitivity of the solution to uncertainties in travel times from one customer to the next in a route.  相似文献   
100.
TPS中调节控制点的综合应用   总被引:1,自引:1,他引:0  
提出了在控制系统更新时,利用新系统的控制功能,实现对老系统中一些特殊控制回路的控制方法.详细介绍了利用Hon-eywell公司HPM中常规控制点的功能,对现场多变量参数求和运算以后进行大可调比参数的控制,以及这种控制回路的控制策略和组态方法.应用结果表明,该控制回路控制精度高、可靠性高.据此提出了充分利用系统软件提供的各种功能模块,解决生产实际问题的方法.  相似文献   
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