Object-oriented data communication for loosely coupled control

The following discussion and examples are based on an object-oriented model for distributed and loosely coupled information systems. The model is used as a framework for a form-based application generator. Capabilities for loose coupling between workstations are illustrated with application examples.     

Secrets to success and fatal flaws: the design of large-display groupware

Research in the field of large-display groupware applications has yet to yield a killer app, a common look and feel for applications, or a set of broadly applicable design principles. It's therefore difficult to understand what constitutes a successful large-display groupware application and what affects their adoption. Although large-display groupware faces many of the same adoption and use challenges as conventional desktop groupware, how people perceive and interact with large-display groupware yields some unique challenges. We've built and evaluated several large-display groupware systems that address various workgroups, functions, and environments. This experience has given us broad expertise regarding the social dynamics and technical challenges surrounding large-display groupware's design. To enhance our understanding of these challenges, we've also undertaken a broad survey of existing large-display groupware systems to understand how their purpose, design, and deployment affect the success of their integration into everyday tasks and practices.     

A graph coloring approach to the deployment scheduling and unit assignment problem

We address one of the external factors of personnel inventory behavior, deployments. The configuration of persistent unit deployments has the ability to affect everything from individual perceptions of service palatability to operational effectiveness. There is little evidence to suggest any analytical underpinnings to the U.S. Army deployment scheduling and unit assignment patterns. This paper shows that the deployment scheduling and unit assignment problem can be formulated as an interval graph such that modifications to traditional graph coloring algorithms provide an efficient mechanism for dealing with multiple objectives.     

J2EE平台上基于Web Services的数据集成研究

数据集成是共享分布的异构数据资源的核心问题.在分析常用数据集成技术的基础上,结合Web Services技术和组件技术,提出了基于Web Services和组件技术实现Mediated系统的数据集成方案.最后,以J2EE为平台给出了一种面向服务的低偶合的数据集成框架,中介器和包装器由EJB组件实现,由组件部署的Web服务为用户提供一个透明的统一的接口,实现异地异构数据资源的共享和整合.     

一种基于虚拟菱形网格的传感器节点布置算法

传感器的布置方式有两种,即确定性的和自组织的。通过分析两种布置方式,提出了一个基于虚拟菱形网格的传感器节点布置算法。该算法把两种布置方式综合在一个统一的平台内,能够形成一个最小连通支配集;保证传感器区域内无“盲区”;对不同的应用,可设置不同的感知或连通覆盖度。该算法在性能和效率上优于基于虚拟力的移动传感器布置算法,其灵活性使网络具有更广泛的适应性。     

Automatic load change coordinated control of air separation units

An automatic load change coordinated control system is developed for strongly coupled and nonlinear air separation units. Firstly, a loosely coupled model is established to solve the tight coupling problem and a robust control strategy integrated with loosely coupled model and priority setting of controlled variables is formed. Secondly, an incremental load balancing calculation method is proposed to handle the nonlinearity and the external target of backflow valve opening is adjusted in real time to solve the hysteresis characteristic. Finally, the comprehensive energy consumption decreases by 2% through deploying the designed automatic control system in an actual air separation unit.     

基于J2EE的分布式Web应用系统框架设计

提出基于J2EE与XML的分布式Web应用系统框架,整合、提出一种开发框架,从而保证系统具有松耦合性和易扩展性,为企业级的计算模型开发以及多层应用结构应用的部署提供了良好的解决思路.     

A mashup based framework for multi level healthcare interoperability

Healthcare delivery is evolving from disease-centered to patient-centered care delivery where patients are active participants in their healthcare delivery. This calls for more communication and collaboration among all healthcare actors. There is also an increasing demand for personalized healthcare systems that provide effective information management, facilitate communication and collaboration, and support applications to meet user requirements. To address these challenges, we need to advance the integration and interoperability of healthcare applications in a controlled manner. Drawing upon a conceptual model from a collaborative care case study, we identified a set of interoperability requirements and developed a Mashup based interoperability framework. Our framework allows patients and other healthcare actors to engage in collaborative processes through online applications facilitated by mashups. We then use proof-of-concept implementations to demonstrate how our framework is able to facilitate different types of interoperability. We believe that collaborative technologies such as mashups can implement process interoperability requirements to support collaborative care delivery, particularly for asynchronous care delivery.     

城市车载网络的路边单元部署机制

在支持车路通信的城市车载网络中,路边单元的部署方案影响着整个车载网络的性能,而传统的部署方案采用无线自组织网络中的布点方式,未充分考虑道路网络的拓扑结构和车辆移动的规律性,导致部署成本高和资源浪费.因此,本文提出了一种基于路口优先级和部署均匀性的路边单元部署机制,称为PUD(intersection Priority and deployment Uniformity based roadside unit Deployment scheme),保证其服务能力的同时降低部署成本.PUD以交叉路口作为路边单元的候选部署点,综合车辆移动特性和路网拓扑,以车流密度、连接中心性和公共交通线路数作为主要因素,计算每个交叉路口处部署路边单元的优先级,作为部署位置选择的标准.为了提高部署均匀性,避免路边单元的覆盖范围重叠导致的资源浪费,设置了四条部署约束规则,即位置约束、范围约束、优先级约束和覆盖约束,满足条件的交叉路口可被选择为部署位置.实验表明,与其他路边单元部署方案相比,PUD具有更低的部署成本、更高的覆盖率和车辆覆盖时间比例.     

Network politics in an educational organization

The electronic mail (EM) network in a large, multi-campus community college district was used by some employees to gain support for positions contrary to those of the leadership. The case study offered an opportunity to look at technology within an organizational setting. It raised questions about the loose coupling of the educational organization's technical and authority systems, about the strength of coupling among employee groups during the incident, about the boundaries of the EM political activists, and about the power manifested within educational organization's technical and authority systems. A variety of research methods (stages of event progression, fantasy types associated with consciousness-building, and evidence of user technical and rhetorical skills) were used to answer questions about the organization's loosely coupled systems during the EM political incident. Notes were taken of conversations and more formal interviews. From this the technical and authority systems of the institution were described and compared. Results indicated that (1) the loose coupling of the technical and the authority systems made the EM political incident possible; (2) employees were more tightly coupled on organizational goals and more loosely coupled on organizational means; (3) political activists did not make full use of the EM's political medium potential; and (4) when the college district's administration refused to limit anyone's use of the EM network, they reinforced the integrity of both the authority and the technical systems.

Implications included: (1) the potential of some of the research methods for EM study, especially fantasy theme analysis; (2) a political interpretation of EM language, especially flaming; (3) the importance of technical and rhetorical skills for mature EM users; and (4) the role of the authority and technical systems in the debate about appropriate EM network use within an organization.     

Gamma deployment problem in grids: hardness and new integer linear programming formulation

Vehicular networks are mobile networks designed for the domain of vehicles and pedestrians. These networks are an essential component of intelligent transportation systems and have the potential to ease traffic management, lower accident rates, and offer other solutions to smart cities. One of the most challenging aspects in the design of a vehicular network is the distribution of its infrastructure units, which are called roadside units (RSUs). In this work, we tackle the gamma deployment problem that consists of deploying the minimum number of RSUs in a vehicular network in accordance with a quality of service metric called gamma deployment. This metric defines a vehicle as covered if it connects to some RSUs at least once in a given time interval during its whole trip. Then, the metric parameterizes the minimum percentage of covered vehicles necessary to make a deployment acceptable or feasible. In this paper, we prove that the decision version of the gamma deployment problem in grids is NP‐complete. Moreover, we correct the multiflow integer linear programming formulation present in the literature and introduce a new formulation based on set covering that is at least as strong as the multiflow formulation. In experiments with a commercial solver, the set covering formulation widely outperforms the multiflow formulation with respect to running time and linear programming relaxation gap.     

一个组织间松散耦合跨组织工作流的仿真模型

为了解决松散耦合跨组织工作流的仿真建模问题,以染色Petri网为理论基础,将颜色集、染色函数、资源库所、等待库所、忙库所、开始变迁、结束变迁、角色、组织、时间函数、资源函数和变迁函数引入到IOWF(inter-organizational workflow),提出了染色多维跨组织工作流网CMD/IOWF(colored multi-dimension/IOWF).基于CMD/IOWF,讨论了组织间松散耦合跨组织工作流中多个不同项目工作流实例通过资源共享和活动同步相互耦合以及与仿真相关的资源约束和时间的建模问题.通过定义输入/输出、状态、事件、时间推进函数和状态转移函数,给出了一个组织间松散耦合的多个跨组织工作流的仿真模型.基于该模型的仿真分析可以求解组织间松散耦合跨组织工作流的关键性能指标,包括:对应项目工作流实例的平均执行时间、平均执行成本及其关于组织的分布,各项目的资源利用率.最后,以一个实例验证了提出模型的有效性.     

W4H:一个面向软件部署的技术分析框架

部署是软件生命周期中的一个重要环节,是软件生产的后期活动,通过配置、安装和激活等活动来保障软件制品的后续运行.为了系统地了解软件部署的现状和最新进展,建立了一个多侧面、细粒度的分析框架——W4H,以对该领域的主要研究工作和系统工具进行概括分析.该框架从软件部署的概念和面对的问题空间出发,由5个侧面、12个维度构成,覆盖了软件部署方法中主体、客体、适用范围、方式策略和过程支持能力等多个方面.基于W4H分析框架,对当前具有代表性的软件部署方法与技术进行分析和总结.案例研究结果表明,该分析框架能够对软件部署方法与技术进行较为全面的分析,对软件系统部署方法和技术的选择及开发具有重要的指导意义.     

Efficient peerGroup management in JXTA-Overlay P2P system for developing groupware tools

With the fast development of IT technologies, virtual organizations are more and more present in the current collaborative work and learning activity. For instance, many subjects in virtual distance learning are organized as online groups of students, who use groupware tools to complete their learning tasks. In this paper, we address the efficient management of peer groups in JXTA-based P2P systems as a key issue in many P2P applications that use peer group as a unit such as for remote execution of tasks in parallel and distributed applications. From this perspective, we consider peer grouping as the basis in the development of groupware tools in P2P systems.     

P2P流媒体系统服务器部署的优化设计

P2P流媒体系统中,内容服务器提供源数据并驱动数据扩散,是系统的重要组成部分,其部署方案会影响整个系统的流量变化.分析了服务器的优化部署问题,从服务器负载均衡、主干网内流量最小和调度代价最小3个优化目标建立系统模型,并给出了各个优化目标的算法实现,包括基于负载均衡的贪心算法和基于0-1规划的分支定界算法.最后,通过仿真实验验证了服务器部署方案对系统的影响,实验结果表明不同的优化目标满足了不同的部署需求.     

改进的有向传感器网络多中心部署算法*

针对单个节点非均匀有向传感器网络部署的局限,提出了多中心的节点部署算法PFMCA(Potential Field based Multi-Center Algorithm)。在部署中心概念及移动策略的基础上,能够保证多个监测中心的覆盖质量,同时实现对其余区域的均衡且尽可能高效的覆盖。仿真实验表明,本文提出的算法实现了对多个重点监测区域的高覆盖质量,且在多中心点间的区域具有更好的覆盖均衡性。     

基于Spring容器的JBPM流程文件部署模型

随着软件开发技术的不断更新,工作流系统越来越多地应用到企业业务流程当中。Spring技术的成熟,使得如何高效地把JBPM框架整合进Spring框架成为了整个系统搭建的关键。在分析现有部署模型的基础上。结合流程构件开发中遇到的流程文件部署问题,提出了一种利用服务器启动参数控制部署信息并结合Spring Modules反转控制部署的部署模型,这个模型使流程文件部署独立于J2EE系统,对J2EE框架的集成更加松耦合。     

A business model for deploying Web services:A data-centric approach based on factual dependencies

The standards XML, SOAP, WSDL and UDDI allow (i) services to be accessed and executed via the Web; and (ii) a loose coupling of these services. Thanks to these standards, Web services technology is becoming not only a de facto integration standard, but also a de facto Internet standard instance of the SOA architecture. However, the deployment of such a technology is still hindered by some technical as well as methodological issues. This paper proposes a business model with multiple interfaced abstraction levels as a framework to methodologically deploy Web services technology with respect to SOA architecture. The attributes describing the business objects and coordination artifacts as described in the highest abstraction level of the business model, i.e. the universe of discourse, are aggregated according to a time/space constraint called factual dependency. Each aggregation of factually dependent attributes is validated with regard to an actual business event. The aggregation is then interfaced to lead to a well-specified Web service. The resulting comprehensive set of consistent Web services are then registered in a public or a private UDDI to be discovered and invoked by any business process. The proposed Web services generation process aims at unlocking and turning informational assets into actions. It differs from the current IT perspective approaches that generate Web services directly from redundant and inconsistent elements in the enterprise information systems.     

基于J2EE与SOA的航运电子商务平台的研究和实现

SOA(Service-Oriented Architecture)是一种架构模型,它可以根据需求通过网络对松散耦合的粗粒度应用组件进行分布式部署、组合和使用。该文主要针对某航运电子商务平台中存在的业务适应能力差等问题,提出了采用SOA开发框架。通过使用基于J2EE标准的Web服务技术,将其划分为客户端调用层,Web服务发布层和Web服务实现层,保证了系统的稳定、高效、松耦合和易于集成。     

简论企业ERP系统部署架构以及配套BI系统的部署架构设计

对企业ERP和BI系统的部署架构进行对比分析,找出适合企业自身的架构设计,降本增效。