基于Agent技术的敏捷虚拟企业信息系统的结构及其原型系统研究

在分析敏捷虚拟企业定义、特征的基础上,提出了基于Agent技术的敏捷虚拟企业信息系统框架结构,并证明智能体技术在构建敏捷虚拟企业信息系统中的有效性。     

虚拟企业环境下项目任务分解和进度控制策略

分析了在虚拟企业（VE）环境下项目管理的特点及其过程模型，给出了一种适合虚拟企业运营特点，提高项目分解效率的项目任务分解法；同时将项目管理与WfMS相结合，提出一种过程框架的方法来解决VE运营过程中任务的集中和分布控制问题。     

面向AVE的企业过程再设计仿真优化系统的研究与设计

文章建立了敏捷虚拟企业产品过程再设计的基本框架，提出了基于活动链的过程缺陷分析方法，总结了进行过程结构优化设计的ＥＳＩＡ原则，并基于工程网络图的原理开发了一套过程仿真系统对企业过程原型进行模拟分析评价。     

基于敏捷软件开发方法的基金管理信息系统开发

敏捷软件开发是一种面临迅速变化的需求快速开发出高质量的软件产品软件的新方法。介绍了敏捷软件开发的主要内容,特别是XP和AM,并以一个基金管理信息系统的开发为例,展示了实际应用过程。     

Design of agile supply chain assessment model and its case study in an Indian automotive components manufacturing organization

Agile Manufacturing (AM) paradigm is fast instilled in modern organizations. AM enables an organization to evolve products and services quickly and economically in response to the customers’ dynamic demands. The effectiveness of AM is largely determined by the performance of Agile Supply Chains (ASC). In order to assess their performance, an ASC assessment model was reported in this research paper. This model is encompassed with agile supply chain attributes whose performance levels need to be determined for assessing the overall ASC performance of the organization. The computation was performed using fuzzy logic approach. The working of this model was examined by conducting a case study in an Indian automotive components manufacturing organization. The experience gained by conducting this case study favored the use of a computerized system which will ensure accuracy of computations involving fuzzy logic.     

信息网格中基于虚拟组织的动态映射模型研究

实现信息集成、有效信息共享一直是科研和产业界面临的一个挑战,网格技术为解决这一问题提出了解决方案。提出了一种在信息网格环境下基于虚拟组织的信息资源模型,给出了在该模型中如何动态映射虚拟资源和物理资源的方法,并给出相应的算法和分析。     

Selection of partners in virtual enterprise paradigm

Agility is the competitive advantage in the global manufacturing environment. It is believed that the agility can be realized by dynamically reconfigurable virtual enterprise. However, the configuration of virtual enterprises is a challenge to us. In selecting the partners for the reconfiguration of virtual enterprise, many factors should be taken into consideration. However, the manufacturing cost and time to market are the most important factors. In this paper, in considering the completion time as a constraint we model the partner selection problem by an integer programming formulation to minimize the manufacturing cost. The formulation is then transformed into a graph-theoretical formulation and a 2-phase algorithm is developed to solve the problem. In the first phase, a polynomial bounded algorithm is proposed to find the earliest completion time, so we obtained a feasible solution. In phase 2, we improve the solution by exchanging the candidate partners in keeping the solution in the feasible region. Although we may not find the optimal solution for the problem by the improvement algorithm, the objective is reduced iteration by iteration. Thus, the algorithm is efficient and can be applicable to practical problems. An illustrative example is presented to show the application of the proposed algorithm.     

Hierarchical control policy for dynamic resource management in grid virtual organization

This paper proposes a hierarchical control system in grid virtual organization. The hierarchical system can be decomposed into multiple application groups, which can be further decomposed into multiple applications. At the top of the hierarchy, the global controller controls the gross allocation of resources to the groups. At the next level down, the group controller coordinates the local deployments of all applications that consume the local allocation of resources. At the lowest level, the local controllers adjust the local resource usages to optimize the utility of single application. The hierarchical control system considers all applications and coordinates all layers of grid architecture upon any changes. According to different time granularity, we adopt a different control scheme. The global control considers all applications and coordinates three layers of grid architecture in response to large system changes at coarse time granularity, while local control adapts a single application to small changes at fine granularity. This paper adopts utility-driven cross layer optimization for grid applications to find a system wide optimization and solves the cross-layer optimization by using pricing based decomposition. A set of hierarchical utility functions is used to measure the performance of the grid system that follows the system, group and application hierarchy. This paper uses total utility to measure the overall quality of grid system. The experiments are conducted to test the performance of the hierarchical control algorithms.

Categorization of risk factors for distributed agile projects

ContextOrganizations combine agile approach and Distributed Software Development (DSD) in order to develop better quality software solutions in lesser time and cost. It helps to reap the benefits of both agile and distributed development but pose significant challenges and risks. Relatively scanty evidence of research on the risks prevailing in distributed agile development (DAD) has motivated this study.ObjectiveThis paper aims at creating a comprehensive set of risk factors that affect the performance of distributed agile development projects and identifies the risk management methods which are frequently used in practice for controlling those risks.MethodThe study is an exploration of practitioners’ experience using constant comparison method for analyzing in-depth interviews of thirteen practitioners and work documents of twenty-eight projects from thirteen different information technology (IT) organizations. The field experience was supported by extensive research literature on risk management in traditional, agile and distributed development.ResultsAnalysis of qualitative data from interviews and project work documents resulted into categorization of forty-five DAD risk factors grouped under five core risk categories. The risk categories were mapped to Leavitt’s model of organizational change for facilitating the implementation of results in real world. The risk factors could be attributed to the conflicting properties of DSD and agile development. Besides that, some new risk factors have been experienced by practitioners and need further exploration as their understanding will help the practitioners to act on time.ConclusionOrganizations are adopting DAD for developing solutions that caters to the changing business needs, while utilizing the global talent. Conflicting properties of DSD and agile approach pose several risks for DAD. This study gives a comprehensive categorization of the risks faced by the practitioners in managing DAD projects and presents frequently used methods to reduce their impact. The work fills the yawning research void in this field.     

基于VPN的协同设计网络模型

该文介绍了VPN的概念和工作原理,在此基础上提出了基于VPN的协同设计网络模型,分析了基于VPN的协同设计网络的特点和安全性问题,最后给出了一个基于VPN的协同设计网络的解决方案。     

基于协作型VMM的虚拟机执行环境动态配置模型

针对当前各类虚拟机监控器(VMM)在定制虚拟机执行环境过程中灵活性不足、可用性不强方面的问题,提出并设计了一种用户动态配置虚拟机执行环境的模型,并在协作型VMM之上进行了实现。结合Intel VT-x技术的实现机制,充分利用虚拟机控制结构(VMCS)中的执行控制域特性,通过为用户提供接口,对虚拟机配置文件进行操作,实现对虚拟机执行环境的实时动态配置。用户利用该模型能够快速构建具有不同运行时特性的虚拟机执行环境。测试结果表明,该模型能够提高VMM的可用性。     

虚拟企业ERP的结构与功能研究

分析了ERP系统在虚拟企业中应用所存在问题,研究了适用于虚拟企业的资源计划系统VERP的结构与功能,指出VERP须采用基于Internet的B/S模式,并提出了VERP的功能框架。     

一种基于网格虚拟组织的跨域访问控制算法*

在网格中,主机存在于不同的信任域中,在主机间建立互信是实现资源共享、协同工作的前提,为资源的访问建立规则是实现资源安全的基础。网格中的访问控制算法旨在解决上述两个问题。结合安全数据库的访问控制策略,融入基于身份和基于行为的访问控制思想,实现了以任务发起者为中心的网格虚拟组织的跨域访问控制,并对其中建立互信的核心算法进行了BAN逻辑推理。     

敏捷供应链静态调度模型及其贪婪算法

针对确定性市场需求下的敏捷供应链(ASC)调度具有批量和时间双重约束的问题,根据供应层级关系建立多级供应链结构模型(SCSM),在此基础上设计调度问题的线性规划(LP)模型及其两阶段求解算法：第一阶段的最短响应时间调度贪婪算法判定供应链系统对需求批量和时间约束满足与否;第二阶段的精益调度贪婪算法求解以最小化供应链库存成本为目标的最优调度方案。最后通过算例验证了模型和算法的实用性和有效性。     

面向动态虚拟网络请求的虚拟网络映射算法

针对虚拟网络请求资源动态变化的实际情况,提出了面向动态虚拟网络请求的虚拟网络映射（DVNR-VNE）算法。以混合线性规划理论为基础,采用多队列的方式分别对不同类型的虚拟网络请求进行预处理,建立了以最小化映射代价和最小迁移代价为优化目标的映射模型,优先映射需要释放资源的请求以获得更多的资源支持其他的虚拟网络,对新到来的虚拟网络请求采用优化后的虚拟网络映射（WD-VNE）算法进行映射。仿真实验表明,该算法降低了链路映射成本和迁移成本并获得了较高的虚拟网络请求接受率。     

私有云平台的虚拟机内存调度策略

在私有云平台中,现有的方法无法灵活地对虚拟机内存资源进行有效的监控和分配。针对以上问题,提出了内存实时监测和动态调度(MMS)模型,利用libvirt函数库和Xen提供的libxc函数库实现了对虚拟机内存紧缺、内存空闲时的实时监测和动态调度,并且提出虚拟机迁移策略,有效地缓解宿主机的内存紧缺问题。最后选取一台物理机作为主控节点,两台物理机作为子节点,利用Eucalyptus搭建一个小型的私有云平台。结果显示,当宿主机处于内存紧缺状态时,MMS系统通过启动虚拟机迁移策略有效地释放了内存空间;当虚拟机占用内存逼近初始最大内存时,MMS为其分配新的最大内存;当占用内容降低时,MMS系统对部分空闲的内存资源进行了回收,而且释放内存不超过150MB(最大内存512MB)时,其对虚拟机性能的影响不大。结果表明该模型对私有云平台中虚拟机内存进行实时监测和动态调度是有效的。     

基于动态人工免疫的邮件分类算法研究

使用虚拟基因库技术,对用于邮件分类的人工免疫系统（AISEC）进行改进,提出了动态人工免疫分类算法（DAICA）模型,改进了AISEC的抗体更新过程。当分类正确时,充分利用参与正确分类的抗体,快速改善抗体质量;当分类错误时,不再是简单地将参与错误分类的抗体直接移去,而是对这些移去的抗体进行体细胞高频变异,以保持先前遇到的抗原信息。还研究了新算法DAICA中使用的参数α与β对算法性能的影响。实验表明,这种改进可以提高分类准确率。     

虚拟企业专业搜索引擎中个性化用户系统设计与实现

提出了一个由用户端和用户代理组成的个性化用户系统．用户可以通过它完成查询和对搜索结果的评价，同时用户系统还会根据对用户兴趣信息的总结，自动产生符合用户兴趣方向的虚拟企业黄页，从而大大提高搜索过程的个性化水平。     

基于Web服务架构的动态虚拟企业伙伴选择

在研究基于Web服务架构的动态虚拟企业理论基础上,提出一种支持企业扩展QoS约束和大规模的动态虚拟企业合作伙伴选择模型,对传统QoS进行扩展,利用QoS监控系统对企业扩展QoS进行实时监控和处理,给出该模型下的伙伴选择流程,并分析伙伴选择实现中的关键问题。对模型性能进行评价,实验结果表明了模型的合理性和可行性。     

Head-mounted display versus desktop for 3D navigation in virtual reality: a user study

Virtual Reality (VR) has been constantly evolving since its early days, and is now a fundamental technology in different application areas. User evaluation is a crucial step in the design and development of VR systems that do respond to users’ needs, as well as for identifying applications that indeed gain from the use of such technology. Yet, there is not much work reported concerning usability evaluation and validation of VR systems, when compared with the traditional desktop setup. The paper presents a user study performed, as a first step, for the evaluation of a low-cost VR system using a Head-Mounted Display (HMD). That system was compared to a traditional desktop setup through an experiment that assessed user performance, when carrying out navigation tasks in a game scenario for a short period. The results show that, although users were generally satisfied with the VR system, and found the HMD interaction intuitive and natural, most performed better with the desktop setup.