Conflict resolution in a knowledge-based system using multiple attribute decision-making

The metarules useful in the conflict resolution are often directly related to the multiple, conflicting, and non-commensurate objectives associated with the problem domain. However, in its current form, the use of metarules for conflict resolution has some drawbacks. Above all, the metarule use in rule selection is not tailored to the current situation or the specific user; it is tailored to the domain expert, whose domain expertise and preferences were used to construct a knowledge-based system. In this paper, we presents a new method for resolving the conflicts of rules in the knowledge-based system, using decision analysis techniques that explicitly incorporate a user’s preference judgments about the rules. To this end, we consider a conflict resolution problem as a multiple attribute decision-making problem. Further, the proposed method allows for user’s preference judgments that are specified not by rigid format but by user-friendly format for the purpose of reducing burden of information specification.We have applied the proposed methodology to an organizational information-oriented service and resource planning, in which there exist multiple conflicting objectives to be considered.     

基于冲突指示和分组隐藏节点冲突解析策略

隐藏节点问题是导致IEEE 802.15.4 协议性能下降的一个重要因素,而在IEEE 802.15.4 中没有给出解决该类问题的具体方案.提出一种基于冲突指示和分组的隐藏冲突避免策略（hidden node collision detection and avoidstrategy,简称HNCDAS）,该策略采用分组方法将IEEE 802.15.4 的CAP 周期划分为多个等分时隙,从隐藏冲突导致的部分破损帧中提取出隐藏节点地址信息,依据当前获得的隐藏关系动态地将节点调整到相应的竞争组,竞争组内的节点在同一周期内仍按照二进制后退方法竞争发送消息,不同的竞争组在不同的时隙发送消息,从而彻底解决隐藏冲突问题.与其他隐藏冲突解析策略相比,HNCDAS 具有额外开销少和动态调整等优点.从理论上证明了该策略的收敛性和解析策略时间的上限,实验结果表明,HNCDAS 在数据传递率、吞吐率和能量利用率等方面都有明显的提高.     

Logic-based formula management strategies in an actuarial consulting system

In many decision support systems, multiple decision methods and models must be combined for solving a complex problem. Expertise is required for selecting, adapting and coordinating appropriate models. This paper describes the design and implementation of a knowledge-based model management system called the Actuarial Consulting System (ACS). The ACS supports actuaries in making pricing decisions in the domain of life insurance. Actuarial knowledge is organized using a graph formalism called Formula Derivation Network (FDN), represented in Prolog as a hierarchy of predicates. On the user level, a Problem Analyzer converts a problem specification by the user into a search problem on the stored collection of FDNs. Using different search strategies, including human expert rules, the Surface Planner generates an efficient solution strategy (sequence of models). At the lowest level, a Plan Executor retrieves or requests model data and issues appropriate function calls to a subroutine library.     

移动科研在线中基于冲突解决的数据同步策略

移动科研在线是协同工作环境套件Duckling的应用之一,但由于移动计算环境存在低带宽、长延迟和频繁断接等问题,当多个用户对同一数据进行操作时容易引发冲突,因此冲突处理和数据同步是该应用的关键问题。为此,提出一种基于冲突解决的数据同步策略。给出数据同步的总体框架和策略,分析冲突处理流程,根据冲突发生的场景,结合用户分类和优先级建立消息推送模型。以移动科研在线中的团队通讯录为例在Android平台上进行原型实现,结果显示,该策略可有效节约网络带宽,提高同步效率,具有良好的用户体验。     

Knowledge representation in MICKEY: an expert system for designingmicroprocessor-based systems

This paper presents the knowledge representation schemes adopted in MICKEY, a knowledge based system for designing microprocessor based systems. MICKEY is essentially a hybrid expert system, using rules and procedures for achieving the different design tasks. We briefly describe the hierarchy of tasks in this problem domain, and emphasize on the refinement paradigm, constraint propagation, conflict resolution and task management strategies adopted in MICKEY. Next, we dwell upon the different knowledge sources and their functions, with respect to the particular design domain. Finally, we present an industrial design, achieved by MICKEY, to demonstrate its applicability     

Coping with conflict in cooperative knowledge-based systems

In this paper, we address a critical issue of cooperative problem solving: the existence of conflict among distributed agents. In particular, we focus our study on cooperative knowledge-based systems. To obtain a better understanding and more balanced judgement of multiagent conflict, we provide a general scheme to study the logical structure of multiagent conflict and rational strategies of coping with it under different situations. Our research finding is that there is no grand unified theory of coping with conflict in performing complex real-world computer supported tasks. Instead, a library of alternative methods should be considered. We discuss four methods: inquiry, arbitration, persuasion, and accommodation. These methods can be combined in an order appropriate to the application domain such that if one method fails, the system will try the next. We point out merits and shortcomings of these methods and illustrate them using several high-level protocols and application examples from a prototype system, the Building Design Network     

Implementation of a knowledge base for interpreting and driving integrated circuit floorplanning algorithms

An experimental integrated circuit floorplanning system is presented. The system uses a combined knowledge-based/algorithmic approach. The knowledge-based system drives the algorithms and interprets their results. This approach permits the automation of tasks that have not been automated before and permits the definition of a floorplanning strategy that successfully manages the complexity of the problem. In addition, the combined approach permits an early pruning of the solution space of the combinatorial floorplanning problem. The implementation of the approach needs a careful choice of knowledge and context representation. The nature of the knowledge domain dictates the use of design quality factors which play an important role in rule conflict resolution. Extracts of the system operation are given with floorplanning examples that show the advantages of the approach.     

Distributed conflict resolution among cooperating expert systems

Abstract: Cooperating experts approach attempts to integrate and coordinate the activities of multiple specialised problem solvers that come together to solve complex tasks such as design, medical diagnosis, business management and so on. Due to the different goals, knowledge and viewpoints of agents, conflicts may arise at any phase of the problem-solving process. Managing diverse expertise requires well-organised models of conflict resolution. In this paper, a model for cooperating experts is described which openly supports multi-agent conflict detection and resolution. The model is based on the idea that each agent has its own conflict knowledge which is separated from its domain level knowledge, and each agent has its own conflict resolution knowledge which is not accessible and known by others. Furthermore, there are no globally known conflict resolution strategies. Each agent involved in a conflict chooses a resolution scheme according to its self interest. The model is described by using an example in the domain of office design and it is compared with other systems.     

Sound conflict management and resolution for virtual-enterprise collaborations

For fulfilling customer requests, enterprises are increasingly part of collaboration networks with peers. Such collaborations, also known as virtual enterprises (VE), are governed by pre-defined contracts that restrict the behaviour of each participating enterprise. However, since each enterprise is autonomous, the potential arises for conflicts during collaboration. In this paper, we extend our earlier work on virtual-enterprise modelling and address the existing gap of conflict modelling, management and resolution in VEs. Our approach works as follows: first, to detect a conflict by analysing the exceptions reported during execution; second, to uncover the conflict type, origin and impact of an exception; and third, depending on the nature of an exception, to implement the appropriate conflict negotiation and resolution strategy among the participating entities of a VE. Crucial to this approach, and serving as one of the key contributions of this paper, is the conflict ontology. This ontology helps to model conflict types along with related exceptions, negotiation and resolution strategies, thereby enabling conflict management and resolution. Throughout this paper, we illustrate our ideas with a running example and also present a detailed evaluation based on a case study from the automotive production domain.     

Design and validation of a knowledge-based system for screeningproduct innovations

The authors' research goal is to develop and validate an expert system that screens innovations prior to commercialization. This is an important research issue because business corporations are highly dependent on innovations for their growth and profitability, yet most corporations suffer from a high rate of new product failure. Few of the existing decision support systems have alleviated this problem, partly because of their inability to deal with nonmathematical (logical) relationships. An expert system for new product planning could save organizations tremendous amounts of resources (such as dollars, time and scientific talent) spent on product failures. The design of the proposed knowledge-based system is built upon the authors' earlier work in this area. The authors have addressed several critical research issues in the development of such a system: choice of the appropriate sources of knowledge, resolution of conflict among human experts chosen for knowledge acquisition, use of knowledge programming techniques that can accommodate uncertainty, and multiple methods of system validation. The research makes several contributions to marketing theory and practice. Most notably, the development of such systems contributes to effective product planning in organizations and enhances resource efficiency. Further, it generates guidelines for capturing and using expertise in highly unstructured decision-making situations such as product management     

化工过程实时故障诊断专家系统的研究与开发

讨论了复杂化工过程实时故障诊断专家系统的设计与实现。对于该系统的系统结构、知识库结构以及推理机的设计进行了详细介绍。尤其是讨论了一种新的知识规则冲突消解策略——前提排序策略以及内存知识库中知识规则选择策略。并以润滑油生产过程为例,讨论了系统的故障诊断过程。实际应用表明,该系统能够及时、迅速地对故障做出响应,满足了生产需求。     

Automated functional design of engineering systems

This paper presents a prototype intelligent system, the knowledge-based functional design automation system (KBFDA) for automating the functional design process of engineering products/systems. An integrated knowledge representation scheme combines rule-based and object-oriented representation methods to represent functions and function related design characteristics in an intelligent design environment. A knowledge-based functional reasoning strategy uses this representation to automatically generate physical behaviors from desired functions or behaviors. The required behaviors are then combined in different configurations to develop a set of potential concept variants that meet the functional requirements and functional constraints given in a design specification. Finally, the variants are ranked according to the degree to which they meet non-functional constraints. The variant with the lowest rank (score) is selected as the best solution. A case study design of a terminal insertion unit is presented to demonstrate the practicality of the proposed approach.     

Cross-paradigm analysis of autonomous agent architecture

Autonomous agent architectures are design methodologies—collections of knowledge and strategies which are applied to the problem of creating situated intelligence. This article attempts to integrate this knowledge across several architectural traditions, paying particular attention to features which have tended to be selected under the pressure of extensive use in real-world systems. We determine that the following strategies provide significant assistance in the design of autonomous intelligent agents: (i) modularity, which simplifies both design and control; (ii) hierarchically organized action selection, which focusses attention and provides prioritization when different modules conflict; and (iii) parallel environment monitoring which allows a system to be responsive and opportunistic by allowing attention to shift and priorities to be re-evaluated. We offer a review of four architectural paradigms: behaviour-based AI; two- and three-layered systems; belief, desire and intention architectures (particularly PRS); and Soar/ACT-R. By documenting trends within each of these communities towards establishing the components above, we argue that this convergent evolution is strong evidence for the components' utility. We then use this information to recommend specific strategies for researchers working under each paradigm to further exploit the knowledge and experience of the field as a whole.     

Detection and resolution of conflicting change operations in version management of process models

Version management of process models requires that different versions of process models are integrated by applying change operations. Conflict detection between individually applied change operations and conflict resolution support are integral parts of version management. For conflict detection it is utterly important to compute a precise set of conflicts, since the minimization of the number of detected conflicts also reduces the overhead for merging different process model versions. As not every syntactic conflict leads to a conflict when taking into account model semantics, a computation of conflicts solely on the syntax leads to an unnecessary high number of conflicts. Moreover, even the set of precisely computed conflicts can be extensive and their resolution means a significant workload for a user. As a consequence, adequate support is required that guides a user through the resolution process and suggests possible resolution strategies for individual conflicts. In this paper, we introduce the notion of syntactic and semantic conflicts for change operations of process models. We provide a method how to efficiently compute conflicts precisely, using a term formalization of process models and consider the subsequent resolution of the detected conflicts based on different strategies. Using this approach, we can significantly reduce the number of overall conflicts and reduce the amount of work for the user when resolving conflicts.     

Correctness criteria for multilevel secure transactions

The benefits of distributed systems and shared database resources are widely recognized, but they often cannot be exploited by users who must protect their data by using label-based access controls. In particular, users of label-based data need to read and write data at different security levels within a single database transaction, which is not currently possible without violating multilevel security constraints. The paper presents a formal model of multilevel transactions which provide this capability. We define four ACIS (atomicity, consistency, isolation, and security) correctness properties of multilevel transactions. While atomicity, consistency and isolation are mutually achievable in standard single-site and distributed transactions, we show that the security requirements of multilevel transactions conflict with some of these goals. This forces trade-offs to be made among the ACIS correctness properties, and we define appropriate partial correctness properties. Due to such trade-offs, an important problem is to design multilevel transaction execution protocols which achieve the greatest possible degree of correctness. These protocols must provide a variety of approaches to making trade-offs according to the differing priorities of various users. We present three transaction execution protocols which achieve a high degree of correctness. These protocols exemplify the correctness trade-offs proven in the paper, and offer realistic implementation options     

Implementation of knowledge-based engineering methodology in ship structural design

The work presents a knowledge-based engineering (KBE) methodology for ship hull structural member design. In the ship design process, many design tasks need the expertise or design experiences to support them. However, the ship design procedure is a complicated process with many labor-intensive activities. Therefore it is necessary to integrate intelligent design process into ship design. An application developed in a KBE system takes design requirements, applies the knowledge stored in the knowledge base and generates a new design automatically. Knowledge-based engineering methods for ship design are put forward, which combine with the theory of intelligent design. A ship deck design case illustrates the feasibility of the proposed approach. The KBE technology provides appropriate suggestions and support, integrates the information, to avoid conflict and errors. Besides, it also achieves knowledge reuse and accumulation, provides reliable technical support for ship design quality, significantly reduces the design cycle, and promotes working efficiency.