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991.
We built three simulation models that can assist rail transit planners and operators to evaluate high and low probability rail‐centered hazard events that could lead to serious consequences for rail‐centered networks and their surrounding regions. Our key objective is to provide these models to users who, through planning with these models, can prevent events or more effectively react to them. The first of the three models is an industrial systems simulation tool that closely replicates rail passenger traffic flows between New York Penn Station and Trenton, New Jersey. Second, we built and used a line source plume model to trace chemical plumes released by a slow‐moving freight train that could impact rail passengers, as well as people in surrounding areas. Third, we crafted an economic simulation model that estimates the regional economic consequences of a variety of rail‐related hazard events through the year 2020. Each model can work independently of the others. However, used together they help provide a coherent story about what could happen and set the stage for planning that should make rail‐centered transport systems more resistant and resilient to hazard events. We highlight the limitations and opportunities presented by using these models individually or in sequence.  相似文献   
992.
In this paper, we link production planning decisions to marketing decisions that involve the price of product groups. The focus of this paper is the development of a closed-loop procedure for aggregate production planning and pricing. We seek to satisfy uncertain demand while minimizing total costs that include material, labour, and inventory holding costs. The procedure is useful for variable demand to update short-term aggregate plans.  相似文献   
993.
Common foundations which underlie thinking in the supply chain management (SCM), Business process re-engineering (BPR) and business process improvement (BPI) philosophies are highlighted. The view that BPR is a new concept is argued against by highlighting die work performed in other fields, namely SCM from the systems perspective. It is argued that those who have already implemented the SCM philosophy will have already travelled the same path as BPR and indeed re-engineered their own processes. Once businesses have integrated their supply chain the greatest benefits will have already been achieved, however system dynamics analysis does show significant on-cost differences dependent on the redesign strategy implemented. A generic structured model for SCM is enhanced through this comparison with BPR with the following characteristics being added; do not be afraid to be radical with respect to internal integration and continually search for step change improvement ideas which can be strategically phased in to positively impact the marketplace.  相似文献   
994.
Abstract. This paper presents four strategies for total productivity optimization of a real-life manufacturing company. These strategies are developed to attain overall growth, cost reduction, upgrading of technical efficiency and management effectiveness. Such strategies have been modelled mathematically by using a nonlinear mathematical programming approach. The model base and the data base used in implementing the strategies can serve as decision support to management for optimizing total productivity.  相似文献   
995.
The post World War II Industrial Revolution has driven production away from the old 'economies of scale' to the new 'economies of scope'. Apparently Japanese led, the associated roots of present good practice on material flow can be traced back in the USA to Jay Forrester and in the UK to Jack Burbidge. Specifically, in the supply chain scenario, Forrester exposed the importance of system structure in relating and integrating information flow with material flow. Similarly Burbidge led the way in exploiting cycle time reduction, synchronization of orders throughout the chain, simplified product structures, and streamlined component flows. This paper unites their contributions to material flow engineering and shows how present day system design methodologies incorporate their ideas on best practice. These principles are particularly relevant to the product delivery process (PDP) which governs material flow in supply chains.  相似文献   
996.
Multimedia is promoted as the technology for the future from the perspective of applications and its role in improving enterprise integration and management effectiveness. As yet few useful applications are found in business and manufacturing. Nevertheless, a growing number of businesses are looking to multimedia for real-life business solutions. Computerized production management systems have enjoyed the same growth and popularity as the personal computers and workstations on which they run. The application of multimedia in various functional areas of manufacturing such as marketing, design and engineering, production and distribution has tremendous potential, taking into account its capacity to integrate text, drawings, full-vector graphics, and full-motion video. Multimedia can also be used as an open development framework for manufacturing applications, especially in CAD, CAE and CAM, by providing users with tools to re-engineer and integrate product and process information. Advances in telecommunications and associated technological developments. Like the personal communicator and the video phone will increasingly add to the importance of multimedia in modern manufacturing. In addition, the future of manufacturing depends crucially on a well-trained employee base. Consequently, interactive video-based training programs appear ideal for jobs that have a high level of human error. In factories, computers and interactive video have been widely used. Realizing the importance of multimedia in manufacturing, especially in the process of enterprise integration and integrating the functional areas of manufacturing, an attempt has been made to investigate the applications of multimedia and identify some future research directions.  相似文献   
997.
Owing to high development and acquisition costs, production systems require very detailed analysis for pre-design specifications, and an adjustment in operating philosophies. Detailed simulation models are one of the most important instruments to achieve this goal; normally the simulator must be custom-built, based on an accurate study of the specific industrial problem. The proposed management and economical analysis uses mathematical meta-models obtained from experimental designs produced by the simulator; today the detail level and precision required is very high, so these kinds of meta-model operate very close to their limit. Here we present a new methodology based on artificial neural networks that produces new types of meta-models which can correctly represent complex industrial systems. In this work we propose an application of this methodology together with a detailed analysis of the model development phase to highlight the potential of this instrument.  相似文献   
998.

For past two decades many organisations have tried to implement integrated information management systems for better production management based on co-ordination of information and therefore activities of different departments. Although Enterprise Resource Planning systems have been in the market for the past decade, many industries find it difficult to implement such systems due to the amount of work involved in streamlining the documentation, customisation and of high costs reported in implementation. An attempt is made through this paper to propose an integrated model, which can be easily understood by production personnel, with specific emphasis on the textile sector.  相似文献   
999.
Capacity planning is a critical element of any successful production planning and control system. A method of rough-cut capacity planning is developed, based on the bill-of-resources approach, that can be used to plan for capacity required for firms in a remanufacturing including overhaul repair operations environment. The modified bill-of-resources approach developed takes into account two major stochastic elements inherent in this environment; probabilistic material replacement factors and probabilistic routing files. A detailed example from an actual repair overhaul operation is presented to illustrate the technique.  相似文献   
1000.
The purpose of this paper is to present a critical assessment of GRAI Grids as a tool for improved manufacturing integration. GRAI Grids, a key component of the GRAI approach, form an integral part of the Strathclyde Integration Method SIM for manufacturing integration. The contribution of the paper is thus to provide a 'third party' view of the effectiveness of GRAI Grids as a modelling tool. The paper presents a brief overview of the GRAI approach, concentrating particularly on the Grids, and an overview of SIM, showing how GRAI Grids are used. The main section of the paper presents an assessment and critique of GRAI Grids. Several benefits and limitations of the Grid as used in SIM and some suggestions for extensions are presented. The paper concludes that the use of the GRAI Grid, within a methodology, provides a unique insight into the behaviour and design of manufacturing information systems and that those who criticize the technique perhaps do so from a lack of awareness of its concepts, principles and advantages.  相似文献   
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