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71.
Distributed planning and control systems for the virtual enterprise: organizational requirements and development life-cycle 总被引:9,自引:2,他引:7
Anto´nio Lucas Soares Ame´rico Lopes Azevedo Jorge Pinho de Sousa 《Journal of Intelligent Manufacturing》2000,11(3):253-270
This paper describes the requirements analysis and system specification of an Order Promise module to be used as part of a broader Decision Support System for production and operations planning of a Virtual Enterprise. This work is part of a broader project with a particular focus on the microelectronics industry which is a good example of Virtual Enterprise, and where a quick response to the customers needs and to unpredictable changes in production conditions is considered a major factor for success. First, the analysis and specification are presented within a development framework that involves the study of organizational issues of semiconductor enterprises. The use of ontological engineering for supporting the communication and shared understanding of the system concepts is explained and a virtual enterprise ontology is outlined. Following the clarification of the concept of virtual enterprise, the generic techno-organizational requirements for the information system are derived. Finally, a specification of the global planning module and a more detailed one regarding the order promise module is presented. 相似文献
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Agostinho de Medeiros Brito Junior Adri?o Duarte Dória Neto Jorge Dantas de Melo Luiz Marcos Garcia Goncalves 《Neural Networks, IEEE Transactions on》2008,19(6):1130-1140
In this paper, we propose a multiresolution approach for surface reconstruction from clouds of unorganized points representing an object surface in 3-D space. The proposed method uses a set of mesh operators and simple rules for selective mesh refinement, with a strategy based on Kohonen's self-organizing map (SOM). Basically, a self-adaptive scheme is used for iteratively moving vertices of an initial simple mesh in the direction of the set of points, ideally the object boundary. Successive refinement and motion of vertices are applied leading to a more detailed surface, in a multiresolution, iterative scheme. Reconstruction was experimented on with several point sets, including different shapes and sizes. Results show generated meshes very close to object final shapes. We include measures of performance and discuss robustness. 相似文献
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Standards-development organizations (SDOs) comprise participants from large and small companies, academia, and the open source community. The participants come with varying backgrounds with regard to copyright and patents in the areas that are being standardized, and the SDOs must deal with these issues in ways that both satisfy the participants (and their employers) and result in useful standards. Each SDO — including the IEEE — has its own intellectual property (IP) policy. This issue, we look at how the IETF handles IP, in an overview cowritten by an attorney who has represented the IETF for some years and the current IETF Chair. 相似文献
74.
Seyed Ali Modarres Najafabadi József Kövecses Jorge Angeles 《Multibody System Dynamics》2008,20(2):163-176
This paper outlines a novel approach to the modeling and analysis of impact involving multibody systems. This approach is
based on an analysis of energy absorption and restitution during impact, using a decomposition of the kinetic energy, which
decouples the parts associated with the spaces of admissible and constrained motions of the underlying unilateral constraints.
Such a decomposition turns out to be useful in the analysis of energy dissipation during impact, and leads to a generalized
definition of the energetic coefficient of restitution, which targets particularly collisions in multibody systems. The applicability
of the approach reported is investigated by conducting an experimental study on a robotic testbed. It is shown that impact
between multibody systems is considerably affected not only by the local dynamics characteristics of the interacting bodies,
but also the configuration of the whole multibody system. The results reported here show that our decomposition can offer
a sound characterization of impact in several problems of multibody systems. 相似文献
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Guidelines for the incremental identification of aspects in requirements specifications 总被引:1,自引:0,他引:1
Jorge García-Duque Martín López-Nores José J. Pazos-Arias Ana Fernández-Vilas Rebeca P. Díaz-Redondo Alberto Gil-Solla Manuel Ramos-Cabrer Yolanda Blanco-Fernández 《Requirements Engineering》2006,11(4):239-263
The desired principle of separation of concerns in software development can be jeopardized by the so-called crosscutting concerns, which tend to be scattered over (and tangled with) the functionality of the modular units of a system. The correct identification of such concerns (and their encapsulation into separate artifacts) is thereby considered a way to improve software understanding and evolution. Pursuing a proper management of concerns from the requirements engineering stage can greatly benefit the entire software life-cycle. In this paper, we propose conceptual guidelines on how to perform the identification of crosscutting concerns in the process of building requirements specifications. We argue that the identification must be carried out in an incremental way, to encapsulate apart the crosscutting concerns even if they have not emerged completely yet.
相似文献
Yolanda Blanco-FernándezEmail: |
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Abstract Strategic research in agriculture and natural resources carried out by international research centers is deemed a public good and should, sooner or later, be put into the hands of development, governmental and non-governmental organizations. However, this research is usually done at specific pilot sites; there is a greater need to know how representative those sites are in relation to the diversity of contexts in other locations. Such is the case with the Challenge Program on Water and Food (CPWF), a global initiative in water research promoted by the Consultative Group on International Agricultural Research (CGIAR), which is developing and implementing strategic research in nine basins located in the tropics of Africa, Asia and South America. Given that resources are not available to collect data from the whole of the region, pilot sites are needed. It is hoped that research outputs obtained in the selected pilot sites can be the basis for scaling out solutions to similar situations in neighbouring or adjacent areas in same or different basins. In order to contribute to the scaling-out process, different classification methodologies were applied to determine how specific watershed basins are representative of larger areas. The Andean eco-region served as a case study but the methods can easily be applied in other regions. The spatial diversity of biophysical and social conditions across the Andes requires careful site selection. Two methods, a combination of Weight of Evidence (WofE) and Logistic Regression (LR) methods and Fast Cluster analysis, were used to determine the similarity of selected sites with those excluded. A 1-km study resolution covering most of the Andes eco-region included annual rainfall, elevation, length of growing period, land cover, roads and population density as the key variables. Results showed complementarities between the two methods in presenting a probability surface of similarity across the Andes and a clustering of similar sites inside and outside the pilot basins. The output information forms a strong basis for devising plans to scale out research findings from the pilot basins to the whole region. 相似文献