Queueing analysis of a server node in transaction processing middleware systems

Quantitative performance modeling of complex information systems is of immense importance for designing enterprise e-business infrastructures and applications. In this paper, we present a traffic model of a server node in a typical transaction processing middleware system as well as a quantitative framework to model and analyze its performance. A multi-class open queueing network model is presented in which multi-class jobs are admitted to a number of server processes sharing hardware resources including the CPU and the disk. We have developed a viable approximation method, which decomposes the dependent components into their independent counterparts while preserving their relevant characteristics. We have conducted queueing-theoretic delay analyses and verified the approach using simulation. Results demonstrate the strength of our approach in predicting delays, elapsed times and other system performance measures.     

Social network,social trust and shared goals in organizational knowledge sharing

The aim of our study was to further develop an understanding of social capital in organizational-knowledge-sharing. We first developed a measurement tool and then a theoretical framework in which three social capital factors (social network, social trust, and shared goals) were combined with the theory of reasoned action; their relationships were then examined using confirmatory factoring analysis. We then surveyed of 190 managers from Hong Kong firms, we confirm that a social network and shared goals significantly contributed to a person's volition to share knowledge, and directly contributed to the perceived social pressure of the organization. The social trust has however showed no direct effect on the attitude and subjective norm of sharing knowledge.     

机载光电传感器图像融合识别的D-S证据理论方法

针对机载光电传感器获得的图像信息的不确定性与模糊性,提出利用D-S证据理论对多图像传感器信息进行融合处理的方法.首先对各图像传感器获得的同一场景图像分别进行预处理,然后对预处理后的图像提取其矩特征,通过与目标图像数据库中图像特征的对比分析,利用灰色系统理论方法获取各传感器的基本概率赋值,最后根据D-S证据理论的组合规则与决策规则获得多图像传感器的融合识别结果.仿真结果表明该方法能提高目标识别的准确度,降低传感器获取的信息的不确定性.     

数据结构教学方法的探讨与研究

本文针对数据结构这门课程在教学中存在的问题．提出了一些解决方法。     

一种基于知识发现的拓展型竞争情报系统

目前,制约竞争情报发展的一个关键问题就是情报的收集与分析手段比较落后,远远不能胜任竞争情报系统所蕴含的特点和功效。本文将竞争情报作为一种特殊的知识,吸纳知识发现理论成果和方法,提升现有竞争情报系统的构造技术,真正做到快速、全面、准确和智能化的竞争情报生成和利用。     

Weight distribution and dual distance

Several results in coding theory (e.g. the Carlitz-Uchiyama bound) show that the weight distributions of certain algebraic codes of lengthn are concentrated aroundn/2 within a range of width n. It is proved in this article that the extreme weights of a linear binary code of sufficiently high dual distance cannot be too close ton/2, the gap being of order n. The tools used involve the Pless identities and the orthogonality properties of Krawtchouk polynomials, as well as estimates on their zeroes. As a by-product upper bounds on the minimum distance of self-dual binary codes are derived.     

A primary influence vertex approach to identify driving factors in complex integrated agri-industrial systems – an example from sugarcane supply and processing systems

Integrated agri-industrial systems (IAISs), such as sugarcane supply and processing systems, are complex systems and hence generally difficult to understand and manage. The large number factors in IAISs coupled with the complex interrelationships among the factors make it challenging to identify the points of intervention for improving their overall performance. Several approaches, such as the network theory and the Theory of Constraints have been used to identify important factors in systems with variations in success. This paper demonstrates a primary influence vertex approach for identifying and ranking the factors that drive the performance of IAISs. The approach is based on comprehensive causal network analyses and was tested in four relatively diverse large-scale sugarcane milling operations in South Africa. Results from the analyses were found to be consistent with the literature and external knowledge of the milling areas as at the time of the study. It is concluded that the approach can proffer a sound basis from which deeper rooted problems in systems can be identified on an ongoing basis. It is, however, recommended that the approach should be systematically compared with other relevant methods that are used to analyse complex systems.     

基于模糊PI控制的交流调速系统研究

传统PI控制器以固定不变的PI参数去处理变化多端的动态过程,很难满足各种工况下的性能指标。针对这一问题,本文将模糊控制理论引入到交流调速系统的PI控制器中,实现PI参数的实时调整,显著地改善调速系统的动态性能。仿真实验表明,在同等实验条件下,模糊PI控制的动态性能优于传统PI控制的性能。     

支付系统实验环境建设探索与研究

支付系统在经济活动中扮演了重要角色,为了让金融及电子商务等专业学生掌握支付系统的业务流程和让科研人员对支付系统进行研究,有必要建立支付系统的实验环境.本文细致深入地分析了支付系统实验环境应具有的功能、建设目标和软硬件环境,对高校开设支付系统相关的课程和建设实验环境提供了有价值的参考.     

试用社会解体理论分析网络犯罪的成因及对策

目前,网络的发展极大推动了人类文明的进步,网络犯罪问题也络绎不绝的出现,而且呈现出平民化、反社会化、加速化、恶性化的特点,因此越来越成为社会关注的重点问题。网络犯罪作为新世纪各国共同面临的社会问题,理应也从社会学角度出发进行研究分析,本文试图应用社会解体理论,从网络犯罪所处的＂虚拟社会＂出发,探究其形成的原因,并提出相应的对策。