Symbolic and numeric knowledge integration in multiple fault troubleshooting

Many expert system researchers have reported in recent years that situation-action symbolic production rules frequently fail to provide adequate knowledge representation schemes without resorting to numeric computation. However, despite the need to integrate symbolic and quantitative computation into one coherent framework of knowledge, surprisingly few architectures have been proposed for achieving this goal. This paper explores the integration of qualitative and numeric processing in expert systems. We address the topic with respect to the construction of expert systems that perform the tasks of design and multiple fault troubleshooting. This paper shows that these tasks can be handled effectively when an appropriate interface is established between the heuristic and the numeric knowledge-based components. Specifically, we demonstrate how to interface heuristic knowledge with non-linear optimization models in order to allow an expert system greater expressiveness. An actual example is presented from the machining domain.     

A generalized expert system for database design

Generalized Expert System for Database Design (GESDD) is a compound expert system made up of two parts: (1) an expert system for generating methodologies for database design, called ESGM; and (2) an expert system for database design, called ESDD. ESGM provides a tool for the database design expert to specify different design methodologies or to modify existing ones. The database designer uses ESDD in conjunction with one of these methodologies to design a database starting from the requirement specification phase and producing a logical schema in one of the well-known data models, namely, the hierarchical data model, the network data model, or the relational data model. The system is evolutive in the sense that an existing methodology can be modified or a novel methodology can be added to the existing ones. GESDD is a menu-driven system and it is coded in Prolog     

Knowledge acquisition and integration tools aiming to support managerial planning in Greek SMEs

Most existing expert systems are defined in structured task domains. However, many real-life decision tasks are novel, unstructured and consequential. To support these tasks, expert systems are needed which provide an integrated environment capable of capturing new knowledge by updating the existing knowledge base. This paper describes the incremental development process of an expert system, from the initial gathering of data up to the development of knowledge acquisition tools and knowledge integration methodologies. The expert system developed addresses managerial planning tasks of Greek small-to-medium sized enterprises (SMEs). The manager sets values for parameters specifying environmental and company characteristics. The expert system responds with suggestions on feasible tactics, objectives and strategies. To cope with the changes of planning situations and also to improve the integrity of the knowledge base as the manager gains experience, knowledge acquisition tools have been introduced. These knowledge acquisition tools, which are manipulated directly by the manager, provide the system with additional knowledge and validate the knowledge already embedded in the knowledge base.     

Rigas: an expert server task in real-time environments

The integration of expert systems in real time environments provides new possibilities to the process control of complex systems. Intelligent tasks working together with traditional control tasks under real time constraints introduce some problems in order to guarantee a response time of the system. In this paper, the use of a a real time expert system for process control, called RIGAS, encapsulated in an expert server task is described. The expert server is formed by an scheduler, a blackboard, and a set of task with real time constraints.     

Corporate ergonomics programme at BCM Airdrie. Boots Contract Manufacturing

The production processes at the BCM Airdrie site range from manual loading tasks in the manufacturing areas to high frequency packaging assembly tasks on the production lines. Both are jobs that are known to carry risk to musculoskeletal health, so an ergonomist was appointed to design and co-ordinate an ergonomics programme for the site to control these risks. This paper details the programme that has evolved to proactively manage musculoskeletal risks in the design of both new and existing equipment and processes. The ergonomics procedures described primarily involve the engineers from all areas of the factory, and the process for ergonomics involvement with engineering design projects is described. Shop-floor personnel involvement is considered to be an essential part of the programme and 'Ergonomics Champions' are being trained on the packing lines to monitor the risks that are sometimes introduced with the different designs of product packaging.     

Participation in job redesign: An evaluation of the use of a sociotechnical tool and its impact

In this article we describe the use of a sociotechnical tool within a company manufacturing photographic products. The tool was used by shop‐floor operators and managers to redesign a group of jobs and tasks prior to the introduction of new technology. The tool involved two stages: (a) generating alternative scenarios of ways to reconfigure existing and new jobs and tasks within the plant; and (b) using a set of decision criteria (e.g., control, skill variety, and opportunity for social contact) to evaluate these scenarios, drawing on established sociotechnical and job design principles. The tool proved to be successful in generating new job designs, reinforcing the value of such design techniques, and highlighting the value of shop‐floor involvement in the design process. However, participation in the design process was not without its problems. We discuss these further in terms of the critical role of the workshop facilitator and the important role played by factors such as selection of participants and their background knowledge. © 2001 John Wiley & Sons, Inc.     

Towards knowledge-based infolog specifications A case study of information engineering

A radically new approach to computing, the so-called knowledge-based information processing is achieving striking success in supporting activities needing logical power, human judgement, reasoning and expertise. It offers universal applicability for problem-solving, in particular in more complex tasks than those presently handled by computer systems. The current state of the art and future prospects for the development of a computer system which either performs expert tasks automatically or is used interactively by experts to increase their productivity are reviewed. The weak points we need to look at, namely the lack of guidelines for building such systems, and some dead ends are indicated. Some new results are expected by applying this key technology to our case study, the construction of a Systems Specification Support System (S4). Its knowledge base written in PROLOG captures and encodes human expertise about the INFOLOG model and INFOLOG specifications, which is made available via consultation to formulate specifications and, possibly, advice. The architecture of the knowledge base is presented by discussing its abstraction levels. This investigation provides also a methodology in structuring a systems analyst's knowledge about an application. This means how to find out the main kinds of objects, including their relationships, in some problem domain.     

Integrating multiple document features in language models for expert finding

We argue that expert finding is sensitive to multiple document features in an organizational intranet. These document features include multiple levels of associations between experts and a query topic from sentence, paragraph, up to document levels, document authority information such as the PageRank, indegree, and URL length of documents, and internal document structures that indicate the experts’ relationship with the content of documents. Our assumption is that expert finding can largely benefit from the incorporation of these document features. However, existing language modeling approaches for expert finding have not sufficiently taken into account these document features. We propose a novel language modeling approach, which integrates multiple document features, for expert finding. Our experiments on two large scale TREC Enterprise Track datasets, i.e., the W3C and CSIRO datasets, demonstrate that the natures of the two organizational intranets and two types of expert finding tasks, i.e., key contact finding for CSIRO and knowledgeable person finding for W3C, influence the effectiveness of different document features. Our work provides insights into which document features work for certain types of expert finding tasks, and helps design expert finding strategies that are effective for different scenarios. Our main contribution is to develop an effective formal method for modeling multiple document features in expert finding, and conduct a systematic investigation of their effects. It is worth noting that our novel approach achieves better results in terms of MAP than previous language model based approaches and the best automatic runs in both the TREC2006 and TREC2007 expert search tasks, respectively.     

On constructing an expert system for contact localization and tracking

This paper presents a growth layered approach to construct an expert system for Contact Localization and Motion Analysis (CLMA). It delineates present difficulties in CLMA approaches and provides a conceptual approach for remedy. Of importance is the inclusion of knowledge of structure and mathematical relationships to the classic If … Then production rules. Also incorporated are the time relationships to depict trends in the growth of the system states. Existing CLMA approaches are severely limited by being unable to utilize various sources of knowledge and by relying almost entirely on human experts to reduce many and diverse uncertainties. Expert system approaches are much needed to provide not only a significant improvement in performance but also to execute expert level tasks quickly and reliably. The growth layered expert system considered in this paper evolves from existing CLMA approaches and as such may not initially follow the precise construction of current expert systems. As the expert system grows from the entry level, it can better meet the demands for multisensor integration, multicontact tracking, and other complex situations in difficult ocean environments. The system configuration integrates the tools of signal/channel analysis, pattern recognition, and artificial intelligence. An example of an entry level multipath ranging expert system is presented.     

SAPT—Knowledge-based CAPP system

The system for automatic programming technology (SAPT system) is a part of the designer-expert system. The new developments in artificial intelligence are promising for design and use knowledge-based expert systems. For a manufacturing process planning knowledge base, the method of knowledge representation and reasoning strategy are given. GT and TT concepts are discussed in detail from a KB approach. Production rules are given for knowledge sources, tasks and meta-knowledge. For two real life, examples, a LISP-program has been written and executed. The results obtained are encouraging and further research is in progress.     

Scheduling support for multicasting sessions in broadband communication networks

Multimedia applications require support from the underlying broadband network at the end-to-end communication level. Multicasting is an important paradigm of end-to-end communication. The root node of a multicasting session is responsible for controlling the session including monitoring, maintenance, and the implementation of the multicasting protocol. The job that controls the multicasting session executes as a group of tasks at the root node of a multicasting tree. The scheduling scheme at the root node should give support to a multicasting session by improving the completion time of the jobs controlling the multicasting session, hence increasing throughput and the probability of admitting new multicast sessions into the system. In this paper, we model the tasks that carry out the multicasting session monitoring and maintenance as a fork-join job executing on a multiprocessor system. We assume that an executing task blocks for device I/O as a part of the activities associated with sending and receiving data packets. We develop two analytic models for scheduling a session control job on a multiprocessor system. The first model allows incoming job tasks to multiplex processors with existing tasks of another multicasting session, while the other model schedules a task of the incoming job to an idle processor. We assume that the overhead of rescheduling a task to another processor is large. We compare the performance of both models and show the range of conditions under which a model outperforms the other. We point out how the results can be used in the design of an adaptive scheduler that uses both models to improve throughput and consequently the probability of admitting new multicast sessions.     

An object-oriented approach to computer-aided design of a plastic injection mould

This paper describes a knowledge-based and object-oriented approach for the design of the feed system for plastic injection moulds. The gating system of a plastic injection mould plays a significant role in producing a quality part. Designing of this gating system entails a great amount of effort from an experienced designer and it is time-consuming. CADFEED (Computer-Aided Design of the FEED system of the plastic injection mould) is developed to accurately and efficiently design the type, location and size of a gating system of a plastic injection mould. This system provides an accurate and fast means of obtaining solutions based on the users' requirements, which are easily handled by the rating algorithm in the system. CADFEED generates acceptable solutions at a lower cost than most traditionally and commercially available analysis packages. This system can be used to verify designs proposed by the design engineers. It can also help novice engineers in the understanding of mould design. Another important feature of CADFEED is that it is a low cost system, which uses AutoCAD and an expert system shell on a personal computer. This feature makes CADFEED easily affordable by small-scale industries.     

基于MVC模式的桥梁处治专家系统研究

专家系统(Expert system简称ES)是模拟人类专家解决问题的智能程序系统。专家系统的主要特征是有一个巨大的知识库,存储着某个专门领域的知识。在解决问题时,用户为系统提供一些已知数据,然后从系统中获得专家水平的结论[1-2]。目前专家系统已经应用到生活中的各个方面,本文着重研究了专家系统在在役桥梁中的应用,并且给出了模型建立方法、系统设计以及专家系统软件的设计流程[3]。最后将该系统应用到具体的实例中,实验证明在役桥梁专家决策系统具有良好的效果[4]。     

The EDL Server for Scheduling Periodic and Soft Aperiodic Tasks with Resource Constraints

In this paper, we are concerned with the problem of serving soft aperiodic tasks on a uniprocessor system where periodic tasks are scheduled on a dynamic-priority, preemptive basis and exclusively access to critical sections. Scheduling of tasks is handled by the Dynamic Priority Ceiling Protocol working with an Earliest Deadline scheduler. Our analysis determines the maximum processing time which may be stolen from periodic tasks without jeopardizing both their timing constraints and resource consistency. It provides the basis for an on-line scheduling algorithm, the EDL Server, to deal with the minimization of response times for soft aperiodic tasks.     

International Ergonomics Association Minutes of the Fifth General Assembly,held in Amsterdam on the 7th of June, 1973

A new method for analysing and describing the posture of the trunk and shoulders was developed and used to describe the posture of workers performing automobile assembly operations. The system used a videotape to create a permanent record of the jobs and a personal computer to perform the clerical and time-keeping tasks associated with posture analysis. In experiments using an experienced analyst to evaluate a videotape, highly reproducible results were obtained. Furthermore, the new system required substantially less time than existing posture analysis methods to analyse and reduce postural data.     

A framework for specifying and monitoring user tasks

Interrupting users engaged in tasks typically has negative effects on their task completion time, error rate, and affective state. Empirical research has shown that these negative effects can be mitigated by deferring interruptions until more opportune moments in a user’s task sequence. However, existing systems that reason about when to interrupt do not have access to models of user tasks that would allow for such finer-grained temporal reasoning. To enable this reasoning, we have developed an integrated framework for specifying and monitoring user tasks. For task specification, our framework provides a language that supports expressive specification of tasks using a concise notation. For task monitoring, our framework provides an event database and handler that manages events from any instrumented application and a task monitor that observes a user’s progress through specified tasks. We describe the design and implementation of our framework, showing how it can be used to specify and monitor practical, representative user tasks. We also report results from two user studies measuring the effectiveness of our existing implementation. The use of our framework will enable attention aware systems to consider a user’s position in a task when reasoning about when to interrupt.     

Expert systems in engineering design: an application for injection molding of plastic parts

The rich development environments of expert system shells provide tools for developing knowledge-based expert systems for complex tasks such as engineering design. The diverse knowledge in engineering design combines heuristics with deterministic knowledge, from multiple sources, and involves complicated, interrelated components. The hybrid capabilities in emerging expert system tools effectively address this diverse knowledge, and facilitate the rapid development of design aids by the engineering designer. A prototype expert system for injection-molded plastic parts demonstrates the utility of expert systems for design applications. The prototype is implemented in an object-oriented, rule-based environment, and incorporates solid modeling software and external material databases.     

Utopia: A load sharing facility for large,heterogeneous distributed computer systems

Load sharing in large, heterogeneous distributed systems allows users to access vast amounts of computing resources scattered around the system and may provide substantial performance improvements to applications. We discuss the design and implementation issues in Utopia, a load sharing facility specifically built for large and heterogeneous systems. The system has no restriction on the types of tasks that can be remotely executed, involves few application changes and no operating system change, supports a high degree of transparency for remote task execution, and incurs low overhead. The algorithms for managing resource load information and task placement take advantage of the clustering nature of large-scale distributed systems; centralized algorithms are used within host clusters, and directed graph algorithms are used among the clusters to make Utopia scalable to thousands of hosts. Task placements in Utopia exploit the heterogeneous hosts and consider varying resource demands of the tasks. A range of mechanisms for remote execution is available in Utopia that provides varying degrees of transparency and efficiency. A number of applications have been developed for Utopia, ranging from a load sharing command interpreter, to parallel and distributed applications, to a distributed batch facility. For example, an enhanced Unix command interpreter allows arbitrary commands and user jobs to be executed remotely, and a parallel make facility achieves speed-ups of 15 or more by processing a collection of tasks in parallel on a number of hosts.     

Improved bounds for hybrid flow shop scheduling with multiprocessor tasks

In this paper, we investigate the problem of minimizing makespan in a multistage hybrid flow-shop scheduling with multiprocessor tasks. To generate high-quality approximate solutions to this challenging NP-hard problem, we propose a discrepancy search heuristic that is based on the new concept of adjacent discrepancies. Moreover, we describe a new lower bound based on the concept of dual feasible functions. The proposed lower and upper bounds are assessed through computational experiments conducted on 300 benchmark instances with up to 100 jobs and 8 stages. For these instances, we provide evidence that the proposed bounds consistently outperform the best existing ones. In particular, the proposed heuristic successfully improved the best known solution of 75 benchmark instances.     

CIMOSA modelling processes

Engineering, integrating and managing complex enterprises requires the understanding, and the ability to partition and simplify their operational complexity. Enterprise modelling supports these requirements by providing means for describing process oriented systems and decomposing those into manageable pieces. However, enterprise modelling requires both a common modelling language and a sufficient modelling methodology. The language provides for common understanding on enterprise models across the industrial community. Modelling methodologies will guide users through the rather complex enterprise modelling tasks. Depending on the skills and the tasks of the modelling person, different methodologies will be implemented in the supporting modelling tool. The paper presents both a methodology for the modelling expert and one for the business user. Whereas the modelling expert will be involved in creating new models, structuring the model contents and developing new modelling components, the business user will use process models for decision support. The latter therefore has a need to modify and adapt enterprise models to represent operational alternatives. A methodology for this type of work has to be based on menus. Menus which are created and maintained by the modelling expert. The business user will mostly work with existing process models. He will evaluate process alternatives and will implement the best solution as the new model of his tasks. This mode of operation will thereby provide for automatic update of the models and will keep the models in sync with the changing reality.