136 research outputs found

    A case-based reasoning approach to improve risk identification in construction projects

    Get PDF
    Risk management is an important process to enhance the understanding of the project so as to support decision making. Despite well established existing methods, the application of risk management in practice is frequently poor. The reasons for this are investigated as accuracy, complexity, time and cost involved and lack of knowledge sharing. Appropriate risk identification is fundamental for successful risk management. Well known risk identification methods require expert knowledge, hence risk identification depends on the involvement and the sophistication of experts. Subjective judgment and intuition usually from par1t of experts’ decision, and sharing and transferring this knowledge is restricted by the availability of experts. Further, psychological research has showed that people have limitations in coping with complex reasoning. In order to reduce subjectivity and enhance knowledge sharing, artificial intelligence techniques can be utilised. An intelligent system accumulates retrievable knowledge and reasoning in an impartial way so that a commonly acceptable solution can be achieved. Case-based reasoning enables learning from experience, which matches the manner that human experts catch and process information and knowledge in relation to project risks. A case-based risk identification model is developed to facilitate human experts making final decisions. This approach exploits the advantage of knowledge sharing, increasing confidence and efficiency in investment decisions, and enhancing communication among the project participants

    Modeling A Green Decision Support System for Data Center Sustainability

    Get PDF
    The objective of this dissertation is developing more energy efficient data centers while focusing on the environment as well as meeting the increasing computing needs. Reliability of data centers will be the number one priority for management; however, the focus will be to implement a design by incorporating free cooling, applying thermal profiling, utilizing data mining, and continuing virtualization to create more efficient green data centers that are good for the environment. Since the fall of 2009, electrical consumption patterns were measured in the main data center for the servers and the air-conditioners at Montclair State University (MSU) to quantify the carbon footprint and the electrical costs. An important outcome of this work is to build a Decision Support System (DSS) for green computing in data centers. A DSS is a computer based application to assist in providing solutions with respect to decision-making to multifaceted problems. In summary, building on our measurements, the objective is to design a DSS for data centers to enhance energy efficiency, reduce the carbon footprint, and promote sustainability science across disciplines

    Retrieval from an image knowledge base

    Get PDF
    With advances in computer technology, images and image databases are becoming increasingly important. Retrievals of images in current image database systems have been designed using keyword searches. These carefully designed and handcrafted systems are very efficient given the application domain they are built for. Unfortunately, they are not adaptable to other domains, not expandable for other uses of the existing information and are not very forgiving to their users. The appearance of full-text search provides for a more general search given textual documents. However, pictorial images contain a vast amount of information that is difficult to catalog in a general way. Further this classification needs to be dynamic providing for flexible searching capability. The searching should allow for more than a pre-programmed set of search parameters, as exact searches make the image database quite useless for a search that was not designed into the original database. Further the incorporation of knowledge along with the images is difficult. Development of an image knowledge base along with content-based retrieval techniques is the focus of this thesis. Using an artificial intelligence technique called case-based reasoning, images can be retrieved with a degree of flexibility. Each image would be classified by user entered attributes about the image called descriptors. These descriptors would also have a degree-of-importance parameter. This parameter would indicate the relative importance or certainty of that descriptor. These descriptors are collected as the case for the image and stored in frames Each image can vary as to the amount of attribute information they contain. Retrieval of an image from the knowledge base begins with the entry of new descriptors for the desired image. Along with the descriptors are the degree-of-importance parameter. The degree-of-importance would indicate the requirement for the desired image to match that descriptor. Again, a variable number of descriptors can be entered. After all criteria are entered, the system will search for cases that have any level of matching. The system will use the degree-of-importance both in the knowledge base about the candidate image(s) and the degree-of-importance on the search criteria to order the images. The ordering process will use weighted summations to present a relatively small list of candidate images. To demonstrate and validate the concepts outlined, a prototype of the system has been developed. This prototype includes the primary architectural components of a potentially real product. Architectural areas addressed are: the storage of the knowledge, storage and access to a large number of high-resolution images, means of searching or interrogating the knowledge base, and the actual display of images. The prototype is called the Smart Photo Album It is an electronic filing system for 35mm pictures taken by the average photographer on up to the photo-journalist. It allows for multiple ways of indexing the pictures of any subject matter. Retrieval from the knowledge base provides relative matches to the given search criteria. Although this application is relatively simple, the basis of the system can be easily extended to include a more sophisticated knowledge base and reasoning process as, for example, would be used for a medical diagnostic application in the field of dermatology

    Case Retrieval Nets as a Model for Building Flexible Information Systems

    Get PDF
    Im Rahmen dieser Arbeit wird das Modell der Case Retrieval Netze vorgestellt, das ein Speichermodell für die Phase des Retrievals beim fallbasierten Schliessen darstellt. Dieses Modell lehnt sich an Assoziativspeicher an, insbesondere wird das Retrieval als Rekonstruktion des Falles betrachtet anstatt als eine Suche im traditionellen Sinne. Zwei der wesentlichen Vorteile des Modells sind Effizienz und Flexibilität: Effizienz beschreibt dabei die Fähigkeit, mit grossen Fallbasen umzugehen und dennoch schnell ein Resultat des Retrievals liefern zu können. Im Rahmen dieser Arbeit wird dieser Aspekt formal untersucht, das Hauptaugenmerk ist aber eher pragmatisch motiviert insofern als der Retrieval-Prozess so schnell sein sollte, dass der Benutzer möglichst keine Wartezeiten in Kauf nehmen muss. Flexibilität betrifft andererseits die allgemeine Anwendbarkeit des Modells in Bezug auf veränderte Aufgabenstellungen, auf alternative Formen der Fallrepräsentation usw. Hierfür wird das Konzept der Informationsvervollständigung diskutiert, welches insbesondere für die Beschreibung von interaktiven Entscheidungsunterstützungssystemen geeignet ist. Traditionelle Problemlöseverfahren, wie etwa Klassifikation oder Diagnose, können als Spezialfälle von Informationsvervollständigung aufgefasst werden. Das formale Modell der Case Retrieval Netze wird im Detail erläutert und dessen Eigenschaften untersucht. Anschliessend werden einige möglich Erweiterungen beschrieben. Neben diesen theoretischen Aspekten bilden Anwendungen, die mit Hilfe des Case Retrieval Netz Modells erstellt wurden, einen weiteren Schwerpunkt. Diese lassen sich in zwei grosse Richtungen einordnen: intelligente Verkaufsunterstützung für Zwecke des E-Commerce sowie Wissensmanagement auf Basis textueller Dokumente, wobei für letzteres der Aspekt der Wiederbenutzung von Problemlösewissen essentiell ist. Für jedes dieser Gebiete wird eine Anwendung im Detail beschrieben, weitere dienen der Illustration und werden nur kurz erläutert. Zuvor wird allgemein beschrieben, welche Aspekte bei Entwurf und Implementierung eines Informationssystems zu beachten sind, welches das Modell der Case Retrieval Netze nutzt.In this thesis, a specific memory structure is presented that has been developed for the retrieval task in Case-Based Reasoning systems, namely Case Retrieval Nets (CRNs). This model borrows from associative memories in that it suggests to interpret case retrieval as a process of re-constructing a stored case rather than searching for it in the traditional sense. Tow major advantages of this model are efficiency and flexibility: Efficiency, on the one hand, is concerned with the ability to handle large case bases and still deliver retrieval results reasonably fast. In this thesis, a formal investigation of efficiency is included but the main focus is set on a more pragmatic view in the sense that retrieval should, in the ideal case, be fast enough such that for the users of a related system no delay will be noticeable. Flexibility, on the other hand, is related to the general applicability of a case memory depending on the type of task to perform, the representation of cases etc. For this, the concept of information completion is discussed which allows to capture the interactive nature of problem solving methods in particular when they are applied within a decision support system environment. As discussed, information completion, thus, covers more specific problem solving types, such as classification and diagnosis. The formal model of CRNs is presented in detail and its properties are investigated. After that, some possible extensions are described. Besides these more theoretical aspects, a further focus is set on applications that have been developed on the basis of the CRN model. Roughly speaking, two areas of applications can be recognized: electronic commerce applications for which Case-Based Reasoning may provide intelligent sales support, and knowledge management based on textual documents where the reuse of problem solving knowledge plays a crucial role. For each of these areas, a single application is described in full detail and further case studies are listed for illustration purposes. Prior to the details of the applications, a more general framework is presented describing the general design and implementation of an information system that makes uses of the model of CRNs

    Proposal for a process oriented knowledge management system (PKMS)

    Get PDF
    International audienceIn an increasingly competitive environment, manufacturing companies are more frequently looking to handle the knowledge referentials relating to their redesign processes. They are then able to implement this with less effort and balance out their work capacity for innovation activities, contributing to more significant improvements in their product offering. In this article we propose a conceptual model for the implementation of a process-oriented knowledge tool dedicated to the formalisation of this type of knowledge referential. The implementable nature of this model has been validated by a demonstrator tested on an application case provided by our industrial partner, Renault Powertrain Technology Department

    Enterprise collaborative portal for business process modelling

    Get PDF
    The business processes of manufacturing enterprises have to be dynamic, especially when highly customised products are manufactured or different projects run simultaneously. Another trend in contemporary manufacturing is the necessity for co-operation between geographically dispersed teams. This research presents a new method for modelling business processes enabling co-ordination of dynamic workflows. This thesis focuses first on Business Process Modelling (BPM) techniques and outlines the limitations of the existing methodologies. Similarly, an overview of Enterprise Collaborative Portals (ECP) is conducted and a method for collaborative authoring of dynamic workflows is discussed. Next, the thesis introduces the concept of business process models with feedback based on the Product/process (P/p) methodology. An extension to this methodology, validated through a case study, is developed to overcome some of its limitations. The performance of the proposed extension is analysed and compared with that of the Unified Modelling Language (UML) and its advantages are highlighted. The case study used to demonstrate the capabilities of the proposed approach involves the development of a golf training device prototype using Rapid Prototyping technology. The proposed process modelling methodology is validated in PTC Windchill EIMS, which also serves as a platform for the implementation of the enterprise collaborative portal. The thesis also proposes a benchmarking method for business processes based on the work of Spendolini and the extended P/p methodology. Benchmarking factors are identified and the proposed benchmarking methodology is validated with an example. The benefits of the proposed benchmarking methodology are outlined. Finally, a method for modelling business processes enabling co-ordination of dynamic workflows is presented. The same case study is used to illustrate the algorithm for collaborative authoring of the business process model. As a platform for the implementation of the proposed method, an object-oriented architecture is adopted
    • …
    corecore