Trust and conflict within virtual inter-organizational alliances: a framework for facilitating knowledge sharing

Trust and conflict are inherent issues of any organizational arrangement and central for knowledge sharing; yet they have received limited attention in the literature. In this paper, we undertake an investigation of both phenomena within the context of virtual alliances. A generic framework for understanding the dynamics of trust and conflict within the context of virtual inter-organizational arrangements is presented, followed by an examination of three distinct structural forms of virtual alliances, and strategies for generating trust and minimizing dysfunctional conflict. The paper concludes with an identification of avenues for further research.     

A distributed collaborative product design environment based on semantic norm model and role-based access control

With the boom of Internet Technology, it becomes possible to combine designers from different disciplines into one team to support product design globally. In this paper, a distributed collaborative product design environment is presented to support top-down process oriented product design. In conceptual design stage, the artifact is managed by semantic norm model (SNM). In SNM, the designers can define virtual components at early design stage and instantiate those components at later detailed design stage. By role-based access control (RBAC), different roles with corresponding permissions could be assigned to distributed designers, and the designers could concurrently modify different components of the product relevant to his or her roles. Based on the SNM and RBAC system, a distributed collaborative product design environment is developed and the top-down oriented product design process is demonstrated.     

Uncertainty measures on probability intervals from the imprecise Dirichlet model

When we use a mathematical model to represent information, we can obtain a closed and convex set of probability distributions, also called a credal set. This type of representation involves two types of uncertainty called conflict (or randomness) and non-specificity, respectively. The imprecise Dirichlet model (IDM) allows us to carry out inference about the probability distribution of a categorical variable obtaining a set of a special type of credal set (probability intervals). In this paper, we shall present tools for obtaining the uncertainty functions on probability intervals obtained with the IDM, which can enable these functions in any application of this model to be calculated.     

Association-Based Active Access Control models with balanced scalability and flexibility

In existing Active Access Control (AAC) models, the scalability and flexibility of security policy specification should be well balanced, especially: (1) authorizations to plenty of tasks should be simplified; (2) team workflows should be enabled; (3) fine-grained constraints should be enforced. To address this issue, a family of Association-Based Active Access Control (ABAAC) models is proposed. In the minimal model ABAAC₀, users are assigned to roles while permissions are assigned to task-role associations. In a workflow case, to execute such an association some users assigned to its component role will be allocated. The association's assigned permissions can be performed by them during the task is running in the case. In ABAAC₁, a generalized association is employed to extract common authorizations from multiple associations. In ABAAC₂, a fine-grained separation of duty (SoD) is enforced among associations. In the maximal model ABAAC₃, all these features are integrated, and similar constraints can be specified more concisely. Using a software workflow, case validation is performed. Comparison with a representative association based AAC model and the most scalable AAC model so far indicates that: (1) enough scalability is achieved; (2) without decomposition of a task, different permissions can be authorized to multiple roles in it; (3) separation of more fine-grained duties than roles and tasks can be enforced.     

用RBAC实现CORBA中的访问控制

RBAC是实现访问控制的最有效的技术,CORBA是目前最流行的分布式计算环境之一,文章把RBAC技术用到CORBA应用中,提出了一个基于CORBA的应用系统访问控制的实现模型。     

RBAC模型中条件时态的研究与设计

具有时态特征的角色访问控制（RBAC：Role Based Access Control）模型能够为RBAC控制机制提供动态的时间控制因素，是目前安全模型领域的研究热点。基于对周期理论和时态RBAC模型的研究，本文认为时态不仅能够为模型提供时间维的控制因素，而且模型中的约束也能作用于时间雏形成条件时态平面的控制因素，从而能够进一步提高模型控制的灵活性和多样性。为此，本文提出了条件周期表达式和条件时态的概念，形式化描述了条件时态语义；并通过条件周期事件和角色状态在条件周期下的断言详细论述了条件时态。     

Boundaries and roles: Positioning and social location in the Virtual Math Teams (VMT) online community

As research in Computer-Supported Collaborative Learning (CSCL) expands its understanding of joint knowledge building, new perspectives on how social reality is constructed become necessary. Our research concentrates on the longitudinal or diachronic trajectories of Virtual Math Teams (VMT) at The Math Forum, an online community supporting mathematical inquiry. We investigate how these virtual teams constitute themselves while engaged in building collaborative knowledge. We describe as well, through the lens of positioning theory, the interactional activities that allow participants to situate themselves, others, and their collective knowledge resources over time. Our analysis suggests that positioning work is central to constructing a sustained problem space and illustrates how the configurations of positions and resources that co-participants put forward through interaction might change across a team’s trajectory. These changes constitute and are sensitive to the participants’ evolving reasoning routines and other forms of joint participation uniquely related knowledge building. In addition, we show that the VMT activity system affords participants a level of disciplinary engagement which is partly illustrated by active engagement in positioning work. Finally, we suggest that an interactional approach to roles and participation provides a fruitful framework for researchers, designers, and practitioners interested in understanding and creating engaging CSCL interactions.     

基于角色的访问控制模型的分析与应用

本文介绍了三种访问控制机制:自主访问控制(DAC)、强制访问控制(MAC)和基于角色的访问控制(RBAC),并着重分析了RBAC的三种模型:RBAC96、EHRABC和ARBAC97.最后,介绍了RBAC技术的应用,并给出了一个RBAC的实现模型.     

A negotiation support system for resolving an international trans-boundary natural resource conflict

Post-Soviet legal governance regime of Caspian Sea – the largest inland body of water on earth – remains a source of conflict among the five coastal states of Azerbaijan, Iran, Kazakhstan, Russia, and Turkmenistan. Although different division methods have been suggested for sharing the sea and its valuable resources, the actual gain of the countries is unclear as the proposed methods focus either on the oil and gas or the areal share of the parties. The Caspian Sea Negotiation Support System (Caspian Sea NSS) is developed in this study to delineate optimal boundaries for sharing the sea through simultaneous consideration of the countries' areal and resource shares under different sharing methods. This NSS is a complex optimization model, with a solver engine that provides reliable results with a reasonable computational effort using a heuristic method. The model is run under different division scenarios to evaluate the sensitivity of each party's gain and locations of nautical boundaries to the division rules and the economic values of the resources. Results show a high sensitivity of the optimal nautical boundaries to the division rules and an indirect relationship between the allocated area and resource shares. The findings highlight the necessity for considering utility shares in negotiations as opposed to adopting areal division rules which ignore the utilities and might result in unfair resource allocation. The main policy implication of the study is that clarification of the countries' resource and areal gain under any suggested legal regime for governing the Caspian Sea is essential to the success of the negotiations.