过程模拟研究进展

随着计算机技术的不断发展, 过程模拟在各行各业中的应用越来越广泛. 过程模拟使用模拟模型来模仿业务流程行为, 它可以用于预测和优化系统的性能, 评估决策的影响并向管理者提供决策依据, 也可以用于减少实验成本和时间. 目前, 如何高效地去构建一个可以信任的仿真模型得到了广泛关注. 本文通过追踪、归纳和分析关于构建业务过程模拟模型方法的相关研究文献, 对基于过程模型、系统动力学和深度学习的3种仿真建模方法的流程、优缺点和研究进展进行了阐述, 并探讨了过程模拟面临的挑战和未来的发展方向, 以期为业务过程模拟未来的研究方向提供参考.     

面向换热设备的行业标准件设计

随着应用领域日益扩大,换热设备明显呈现出多品种、小批量、单件生产的趋势。为了缩短产品的设计和生产工期,增强企业的竞争力,基于Solidworks平台建立换热设备标准件库。这不仅避免了设计人员许多重复性劳动,而且使产品的设计效率和制造质量都得到可靠保证。     

汽车覆盖件修边与翻边工序的快速仿真系统

基于UGNX平台开发了覆盖件修边与翻边工序快速仿真系统(TFA).该系统基于有限元逆算法,根据翻边形状反向快速计算修边线尺寸以及翻边成形中可能出现的起皱和破裂等缺陷.由于修边线展开与翻边分析无缝集成UGNX中,避免了CAD与CAE系统数据转换时模型数据丢失和精度损失,缩短了工艺设计周期,为工艺设计人员提供一种方便的修边和翻边快速仿真工具.以汽车后围修边线展开与翻边成形为例,通过TFA计算结果与实验结果的比较,验证了TFA系统算法的可行性与精确性.     

500 kV世博地下变电站环境保护研究

分析了常规地面变电站和地下变电站的环境影响因素.就世博变电站的噪声、热污染、电磁场等方面的环境影响及治理方案提出了相应的技术措施.     

基于FP-Tree的共享前缀频繁项集挖掘算法

在数据挖掘中发现关联规则是一个基本问题,而发现频繁项集是关联规则挖掘中最基本、最重要的问题。提出了基于FP-Tree的共享前缀频繁项集挖掘算法－FP-SPMA算法。构造FP-Tree来压缩事务数据库,通过共享前缀和前瞻剪枝快速减小候选项集,无需递归构造条件模式树,算法性能有明显的提高。     

Headquarter-centered common sourcing management through order coordination and consolidation

It is common for subsidiaries of a group company to use the same types of components for producing similar products. Different subsidiary companies may well procure such components from the same suppliers. This paper studies two sourcing management models. One is the Subsidiary-Autonomous Sourcing Management (SD-ASM) where subsidiaries manage their inventories and place purchasing orders independent of each other. The other is the Headquarter-centered Common Sourcing Management (HQ-CSM) where purchasing orders of subsidiaries are processed centrally through some kind of headquarter coordination. In the SD-ASM model, each subsidiary places replenishment orders at a time interval corresponding to their economic order quantity (EOQ). In the HQ-CSM model, two purchasing order management policies are examined. One is the Order Coordination policy in which common replenishment epochs or time periods are proposed by the headquarter and the subsidiaries are encouraged to coordinate the timing of their orders based on the common replenishment epochs. The other is the Order Consolidation policy in which the subsidiaries combine the quantity of their orders and the headquarter places a combined order with the supplier. In the Order Coordination policy, classic RAND heuristic is used to find the best common replenishment epoch and the best replenishment timing of each subsidiary. In the Order Consolidation policy, the optimal order quantity of the combined order is obtained from a mathematical model. The combined order is then allocated to the subsidiaries according to a proportional allocation rule. A series of numerical studies is conducted to compare the costs of the SD-ASM and HQ-CSM policies. The results show that HQ-CSM outperforms SD-ASM in terms of cost and robustness against demand uncertainties. This achievement is largely due to the economies of process (synergistic ordering process), the economies of scale (large order quantity with price discount) and risk pooling effect (transshipments). The results also reveal that the Order Consolidation policy with a combined order always performs better than the Order Coordination policy with common replenishment epochs especially in face of high demand uncertainties and high service level in the global market.     

面向蛋白质组学数据库的元数据提取与导入工具

本文给出了一种用于提取和导入蛋白质组学元数据的工具,它是"基于元数据的蛋白质组学数据资源共享与整合平台"的一个重要组成部分。该工具被设计为元数据提取、元数据缓存、元数据导入三个模块,为实现从多种蛋白质组学数据源中提取元数据并将其导入元数据库提供了一种有效的解决方案。     

模糊模型在机车车轮故障诊断中的应用

提出了一种改进的能面向高阶T-S模糊推理模型.并将改进型IRBFN的神经模糊模型学习算法应用于车轮的故障诊断当中,提出了一套新的简单、高效的车轮故障诊断方法.仿真结果表明,该方法是有效的.     

局部阴影条件下最大功率点跟踪改进算法

利用MATLAB对光伏阵列在不同阴影情况下的输出特性进行仿真,并总结出光伏阵列可能出现局部最大功率点电压与开路电压之间的规律。根据该规律提出改进型电导增量法,将参考电压依次设为可能出现局部最大功率点的电压以避免漏掉任何一个峰值点,并通过比较这些局部最大功率点,追踪到全局最大功率点。设置参考电压阈值以判断是否存在局部最大功率点,减少搜索时间。仿真结果验证了该算法在有、无阴影的情况下都能准确搜索到全局最大功率点。     

基于Jacobian-Free Newton-GMRES(m)方法的电力系统分布式暂态仿真算法

分布式暂态仿真是实现市场环境下互联电力系统在线一体化仿真分析的有效途径.文中研究了电力系统分布式暂态仿真计算模型,提出了基于Jacobian-Free Newton-GMRES(m)方法的协调求解算法.该算法只需要交换边界母线状态信息,接口简单,实用性强.为了提高算法收敛速度,减少协调求解所需通信次数,提出了自适应预处理和连续修正预处理矩阵、预估边界条件初值及多时步同时协调等改进方法并将其应用于新算法中.测试结果表明,新的暂态仿真分解协调算法收敛快,通信次数少,非常适合在基于广域网络的分布式环境中实现.