1,236,105 research outputs found

    Programmed schedule holds for improving launch vehicle holds

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    Baseline definition and system optimization are used for the analysis of programmed holds developed through prelaunch system analysis. Identification of design specifications for ground support equipment and maintenance concepts, and design specifications are used to describe the functional utilization of the overall flow process

    On Engineering Support for Business Process Modelling and Redesign

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    Currently, there is an enormous (research) interest in business process redesign (BPR). Several management-oriented approaches have been proposed showing how to make BPR work. However, detailed descriptions of empirical experience are few. Consistent engineering methodologies to aid and guide a BPR-practitioner are currently emerging. Often, these methodologies are claimed to be developed for business process modelling, but stem directly from information system design cultures. We consider an engineering methodology for BPR to consist of modelling concepts, their representation, computerized tools and methods, and pragmatic skills and guidelines for off-line modelling, communicating, analyzing, (re)designing\ud business processes. The modelling concepts form the architectural basis of such an engineering methodology. Therefore, the choice, understanding and precise definition of these concepts determine the productivity and effectiveness of modelling tasks within a BPR project. The\ud current paper contributes to engineering support for BPR. We work out general issues that play a role in the development of engineering support for BPR. Furthermore, we introduce an architectural framework for business process modelling and redesign. This framework consists of a coherent set of modelling concepts and techniques on how to use them. The framework enables the modelling of both the structural and dynamic characteristics of business processes. We illustrate its applicability by modelling a case from service industry. Moreover, the architectural framework supports abstraction and refinement techniques. The use of these techniques for a BPR trajectory are discussed

    Space Station Mission Planning System (MPS) development study. Volume 2

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    The process and existing software used for Spacelab payload mission planning were studied. A complete baseline definition of the Spacelab payload mission planning process was established, along with a definition of existing software capabilities for potential extrapolation to the Space Station. This information was used as a basis for defining system requirements to support Space Station mission planning. The Space Station mission planning concept was reviewed for the purpose of identifying areas where artificial intelligence concepts might offer substantially improved capability. Three specific artificial intelligence concepts were to be investigated for applicability: natural language interfaces; expert systems; and automatic programming. The advantages and disadvantages of interfacing an artificial intelligence language with existing FORTRAN programs or of converting totally to a new programming language were identified

    Basic principles of SSM modelling: an examination of CATWOE from a soft perspective

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    This paper examines the SSM technique CATWOE, which focuses on defining necessary elements that together constitute a human activity system from a certain perspective. Despite its recognition within the literature and its numerous uses, there are few studies on how the technique can be improved. This research reflects on each of the elements both from a theoretical and a practical perspective. Findings point to the fact that some of the terms have a meaning in everyday language that differs from its definition within CATWOE. Other concepts are not well-defined. This is unfortunate and may both lead to misunderstandings and limit analysis. The paper points to a number of ways in which the use of CATWOE can be developed in order to further support the process of eliciting novel ideas for future actions. Hence, the overall conclusion is that the elements need to be rethought and some of them renamed

    DESIGN OF COOPERATIVE PROCESSES IN A CUSTOMER-SUPPLIER RELATIONSHIP: AN APPROACH BASED ON SIMULATION AND DECISION THEORY

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    Performance improvement in supply chains, taking into account customer demand in the tactical planning process is essential. It is more and more difficult for the customers to ensure a certain level of demand over a medium term horizon as their own customers ask them for personalisation and fast adaptation. It is thus necessary to develop methods and decision support systems to reconcile the order and book processes. In this context, this paper intends firstly to relate decision under uncertainty and the industrial point of view based on the notion of risk management. This serves as a basis for the definition of an approach based on simulation and decision theory that is dedicated to the design of cooperative processes in a customer-supplier relationship. This approach includes the evaluation, in terms of risk, of different cooperative processes using a simulation-dedicated tool. The evaluation process is based on an exploitation of decision theory concepts and methods. The implementation of the approach is illustrated on an academic example typical of the aeronautics supply chain.supply chain, simulation, cooperation, decision theory, risk

    An analysis of technology gaps and priorities in support of probe-scale coronagraph and starshade missions

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    This paper provides a survey of the state-of-the-art in coronagraph and starshade technologies and highlights areas where advances are needed to enable future NASA exoplanet missions. An analysis is provided of the remaining technology gaps and the relative priorities of technology investments leading to a mission that could follow JWST. This work is being conducted in support of NASAs Astrophysics Division and the NASA Exoplanet Exploration Program (ExEP), who are in the process of assessing options for future missions. ExEP has funded Science and Technology Definition Teams to study coronagraphs and starshade mission concepts having a lifecycle cost cap of less than $1B. This paper provides a technology gap analysis for these concepts

    Definition, Validation and Comparison of Two Population Models for Austria

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    In this work we present two structurally different mathematical models for the prognostic simulation of Austria’s population: A time-continuous, macroscopic system dynamics approach and a time-discrete, microscopic agent-based approach. Both models were developed as case studies of a series of population concepts in order to support models for decision-support in Austria’s health care system. In the present work we want to focus on the definition, the parametrisation as well as especially the validation process of both population-models. The latter was of special interest as it included a cross-model validation with Statistics Austria’s own prognostic model SIKURS

    Definition, Validation and Comparison of Two Population Models for Austria

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    In this work we present two structurally different mathematical models for the prognostic simulation of Austria’s population: A time-continuous, macroscopic system dynamics approach and a time-discrete, microscopic agent-based approach. Both models were developed as case studies of a series of population concepts in order to support models for decision-support in Austria’s health care system. In the present work we want to focus on the definition, the parametrisation as well as especially the validation process of both population-models. The latter was of special interest as it included a cross-model validation with Statistics Austria’s own prognostic model SIKURS

    Process Standardization to Support Service Process Assessment and Re-engineering

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    AbstractService Engineering (SE) discipline is currently supporting companies during the engineering and re-engineering phases of their service offering. With the support of SE methods, companies can undertake their servitization journey with the best premise to gain as well as deliver value to their customers. For this purpose, the Service Engineering Methodology (SEEM) has been proposed. The SEEM entails methods to design service concepts and processes capable of balancing value between customers and the company. Some industrial cases, carried out in collaboration with ABB, a leading provider in power and automation technology, demonstrate the effectiveness of such methodology in the re-engineering of existing services in B2B context. Despite that, the cases show that the SEEM application is time consuming, especially in the validation of the service provision process. Thus, in order to facilitate and speed up the implementation of the methodology, a standard process for service provision becomes relevant. Then, starting from the re-engineering of the existing product-oriented services offered by ABB, this paper aims at laying the foundation for the definition of a reference model and a standard process model for product-oriented service delivery. The results will support the SEEM adoption and the definition of service processes avoiding the design of customized models, that cannot be compared and adapted to different realities. In line with what has been found in literature, the definition of a possible reference model and a preliminary standard process model are presented

    Practical Complexity in Adapting Object Oriented Approach of Systems Analysis and Design

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    Recently, there has been a surge of interest in adapting object-oriented (OO) concepts, UML, and Unified Process of system development in the Systems Analysis and Design texts. However, there is a question of how to best fit these concepts with the existing coherent discussion of structured approach. This paper addresses some of the intricacies of OO concepts such as complexity of diagrams and models, weak links between phases, and lack of support for designing system components. We would like to recommend that there should be a separate text for the OO methodology and it should not present various OO models according to the phases of the traditional structured approach, rather it should focus on the evolution of the models leading to the design of system components. Furthermore, there should be a standard set of models for the OO methodology as well as a clear definition of steps as an analyst moves from one set of models to the next
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