Design of BOM configuration for reducing spare parts logistic costs

This paper proposes an approach to reduce the total operational cost of a spare part logistic system by appropriately designing the BOM (bill of material) configuration. A spare part may have several vendors. Parts supplied by different vendors may vary in failure rates and prices – the higher the failure rate, the lower the price. Selecting vendors for spare parts is therefore a trade-off decision. Consider a machine where the BOM is composed of s critical parts and each part has k vendors. The number of possible BOM configurations for the machine is then k^s. For each BOM configuration, we can use OPUS10 (proprietary software) to calculate an optimum inventory policy and its associated total logistic cost. Exhaustively searching the solution space by OPUS10 can yield an optimal BOM configuration; however, it may be formidably time-consuming. To remedy the time-consuming problem, this research proposes a GA-neural network approach to solve the BOM configuration design problem. A neural network is developed to efficiently emulate the function of OPUS10 and a GA (genetic algorithm) is developed to quickly find a near-optimal BOM configuration. Experiment results indicate that the approach can obtain an effective BOM configuration efficiently.     

基于PKI/PMI的安全Web数据交换

基于XML的数据交换是一种典型的Web应用,通过分析基于服务的数据交换数据,说明在该Web应用中,存在的安全问题和需求,架构一个基于PKI/PMI的安全Web数据交换平台,实现应用层的授权和安全访问控制,并应用在实际中.     

基于退火策略的分布式资源负载均衡算法

针对分布式资源导致的访问热点等一系列问题,建立了一个用于分布式资源退火的处理模型.根据该模型,提出了基于退火策略的分布式资源负载均衡算法;该算法通过访问分类、定向扩散等方法提高了系统性能.性能及试验分析表明,该算法能够减少系统内部通信量,抑制资源扩散的抖动现象等.     

设计模式在基于SystemC的指令译码模块设计中的应用

SoC上的晶体管集成度在不断增长,系统功能越来越复杂,传统的设计方法已经不再适应现在的SoC设计.为了解决这种不适应性带来的"硬件危机",人们初步探索将软件中的面向对象技术引入到SoC设计领域中.设计模式是面向对象技术的核心,可以给同类问题提供比较合理的解决方案.在对软件中的设计模式进行分析的基础上,将用于SoC中的CPU指令译码模块进行基于模式的设计,并给出了部分实现.     

基于遗传算法的粗糙集属性约简算法

为了研究粗糙集理论中属性约简问题,给出了一种属性相对重要度定义,证明了其合理性,并将它应用到基于遗传算法的约简算法中,提出一种启发式遗传算法.算法采用修正策略保证群体进化收敛于最小约简,同时引入属性相对重要度作为启发信息,加快算法的收敛速度.对算法进行的时间复杂度和完备性分析以及数值实验表明,基于遗传算法的粗糙集属性约简算法具有完备、快速收敛等特点.     

一种面向中小企业PDM系统的设计与实现

根据中小企业在信息化建设中对于产品数据管理的实际需求,针对某一具体行业设计了一个适合中小企业的产品数据管理系统。分析系统的开发平台和采用基于．Net框架下采用B／S模式的系统结构,阐述系统具有的图档管理、产品结构和配置管理、项目管理和安全管理等主要功能。应用结果表明,该系统能有效地提高企业对产品数据管理的效率。     

一种基于预测的改进的三步搜索算法

基于对运动矢量分布的中心偏向特性研究,结合零运动预判断,提出了一个基于预测的改进的三步搜索算法(PBITSS),有效地提高了运动估计搜索速度并保持较高的搜索精度.实验结果显示,与三步搜索算法(TSS)相比,图像质量和搜索速度都得到了提高,综合性能高于TSS算法.     

一种面向数据结构的策略翻译技术

策略翻译是目前策略管理研究的难点之一.针对以数据结构表示的策略,提出策略结构五元组概念,增设可扩展的词库,采用XML语言统一描述策略结构,设计通用的脚本分析模块,支持不同设备类型的策略结构,实现透明的策略翻译,提高了策略管理的伸缩性、统一性和透明性.     

Texture synthesis via the matching compatibility between patches

A new patch-based texture synthesis method is presented in this paper. By the method, a set of patches that can be matched with a sampled patch for growing textures effectively, called the matching compatibility between patches, is generated first for each patch, and the set is further optimized by culling the patches that may cause synthesis conflicts. In this way, similarity measurement calculation for selecting suitable patches in texture synthesis can be greatly saved, and synthesis conflicts between neighbouring patches are substantially reduced. Furthermore, retrace computation is integrated in the synthesis process to improve the texture quality. As a result, the new method can produce high quality textures as texture optimization, the best method to date for producing good textures, and run in a time complexity linear to the size of the output texture. Experimental results show that the new method can interactively generate a large texture in 1024 × 1024 pixels, which is very difficult to achieve by existing methods. Supported by the National Basic Research Program of China (Grant No. 2009CB320802), the National Natural Science Foundation of China (Grant Nos. 60773026, 60833007), the National High-Tech Research & Development Program of China (Grant Nos. 2006AA01Z306, 2008AA01Z301), and the Research Grant of University of Macau     

基于模糊Petri网的汽车故障诊断仿真研究

本文将Petri网和模糊推理相结合,建立故障诊断的模糊Petri网模型。其中,用FPN表示模糊产生规则,用Petri网的变迁激活规则进行故障诊断推理,从而分析出异常行为过程间的因果关系,推理出故障的原因及其可信度。以汽车故障诊断为例,建立了基于模糊Petri网的诊断模型。通过仿真分析,验证了模型的正确性和算法的有效性。