隔直电容在弧焊逆变器中抗偏磁能力的分析

本文采用状态平均法建立了隔直电容在知式焊接逆变器中抗偏磁的动态模型，并进行了动态分析，为焊接逆变器的设计提供了理论依据。     

高效动态存储再分配方案与实现

为提高大小和数量都不确定的数据动态存储的空间利用率和处理速度,针对常规系统动态存储分配存在的问题,提出一种高效的动态存储再分配方案。通过减少系统动态存储分配的执行次数,在有效提高存储空间利用率的同时,提高存储空间动态分配的速度,给出动态存储再分配方案的具体实现算法,用实际数据对其性能进行测试。测试结果表明,该方案能节省36％至75％的系统存储空间,分配速度提高了20至50倍。     

仿生波状前缘机翼动态失速控制的数值研究

该文提出了采用波状前缘机翼改善动态失速性能的有效控制方式。通过数值求解雷诺平均N-S方程,对比研究了波状前缘机翼和传统的光滑前缘机翼在动态失速时的力学性能和流动特征,并分析了前缘形状改进和可控拍动参数的影响,探讨有效的控制途径。研究结果表明,在深失速的动态失速控制中,波状前缘翼的复杂涡系能更稳定地附着在上翼面,其力学性能明显优于光滑前缘翼,尤其在大攻角范围内优势明显。波状前缘形状改变对升力能几乎没有影响,但转轴前移、增加拍幅和频率都能提高拍动波状前缘翼的升力。     

基于漏磁原理的钢丝绳探伤仪影响因素研究

介绍了钢丝绳探伤仪漏磁检测原理,并使用有限元分析方法分析了传感器零件的材料、钢丝绳的提离距离及断丝根数等对基于漏磁原理的钢丝绳探伤仪检测结果的影响。分析结果表明,提离距离、断丝根数等因素对探伤仪检测结果影响较大,断丝角度、深度等因素影响较小。     

基于动态联盟的一种身份信任计算模型

在动态联盟中,身份管理是确保信息安全的一种手段,但是随着联盟成员数日益增多,传统的身份管理难以妥善应对当前较为复杂的环境,尤其当成员之间无交互历史时,数据交换的可靠性无法保障。文中研究了不同计算环境中的多种信任管理方法,并把P2P的推荐评价机制应用到动态联盟的身份管理中,提出了一种基于推荐的身份信任管理的算法。在这种算法中,身份的信任值由多因素加权综合而成,其中推荐信任值在算法中起到关键的作用。该算法试图为解决复杂的动态联盟环境下的身份管理问题提供一种途径。     

多平台下动态采集税控数据的技术研究

在商业税收领域中,不同的行业、商家,可能会采用不同的系统平台来完成他们各自的销售任务,这就给国家税收时获取税控数据带来了一定的挑战。本文基于国家信息化标准委员会针对税控收款机的国家标准,提出并实现了一种在多平台下动态采集税控数据的解决方案。     

Continuous State Dynamic Programming via Nonexpansive Approximation

This paper studies fitted value iteration for continuous state numerical dynamic programming using nonexpansive function approximators. A number of approximation schemes are discussed. The main contribution is to provide error bounds for approximate optimal policies generated by the value iteration algorithm.      

Test frame updating in CPM testing of Prolog programs

Category Partition Method (CPM) is a general approach to specification-based program testing, where test frame reduction and refinement are two important issues. Test frame reduction is necessary since too many test frames may be produced, and test frame refinement is important since during CPM testing new information about test frame generation may be achieved and considered incrementally. Besides the information provided by testers or users, implementation related knowledge offers alternative information for reducing and refining CPM test frames. This paper explores the idea by proposing a call patterns semantics based test frame updating method for Prolog programs, in which a call patterns analysis is used to collect information about the way in which procedures are used in a program. The updated test frames will be represented as constraints. The effect of our test frame updating is two-fold. On one hand, it removes “uncared” data from the original set of test frames; on the other hand, it refines the test frames to which we should pay more attention. The first effect makes the input domain on which a procedure must be tested a subset of the procedure’s input domain, and the latter makes testers stand more chance to find out the faults that are more likely to show their presence in the use of the program under consideration. Our test frame updating method preserves the effectiveness of CPM testing with respect to the detection of faults we care. The test case generation from the updated set of test frames is also discussed. In order to show the applicability of our method an approximation call patterns semantics is proposed, and the test frame updating on the semantics is illustrated by an example.

Exact methods and a heuristic for the optimization of an integrated replenishment-storage planning problem

In this paper we study the coordination of different activities in a supply chain issued from a real case. Multiple suppliers send raw materials (RMs) to a distribution center (DC) that delivers them to a unique plant where the storage of the RMs and the finished goods is not possible. Then, the finished goods are directly shipped to multiple customers having just‐in‐time (JIT) demands. Under these hypotheses, we show that the problem can be reduced to multiple suppliers and one DC. Afterwards, we analyze two cases; in the first, we consider an uncapacitated storage at DC, and in the second, we analyze the capacitated storage case. For the first case, we show that the problem is NP‐hard in the ordinary sense using the Knapsack decision problem. We then propose two exact methods: a mixed integer linear program (MILP) and a pseudopolynomial dynamic program. A classical dynamic program and an improved one using the idea of Shaw and Wagelmans are given. With numerical tests we show that the dynamic program gives the optimal solution in reasonable time for quite large instances compared with the MILP. For the second case, the capacity limitation in DC is assumed, which makes the problem solving more challenging. We propose an MILP and a dynamic programming‐based heuristic that provides solutions close to the optimal solution in very short times.     

基于UML可适应的教学考评系统分析与设计

该文给出了UML的概念与要点,应用UML对教学考评系统进行了建模。给出了系统的用例模型、整体结构模型、静态模型、动态模型,并分析了模型对教学考评变化的可适应性。