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941.
Interorganizational systems (IOS) may provide substantial benefits, however many organizations are reluctant to implement them. This empirical research takes a novel approach and develops a model of IOS feasibility, which is based on the Theory of Constraints (TOC). It introduces the notion of maximal infeasibility, which is the highest among the values of five factors: economic infeasibility, organizational infeasibility, technological infeasibility, risks, and lack of financial resources. The highest value was selected because implementation is hindered even if only one of the feasibility requirements is not fulfilled. Data collected from 139 medium and large Israeli business organizations validated the model, and indicated that strategic motivation is the main driving force for an organization to initiate or to join an IOS, while the main barriers are organizational infeasibility issues such as lack of management support or uninterested potential partners. Adopting a TOC approach to IOS implementation may assist organizations to overcome these obstacles and increase the chance of a successful implementation. An earlier shorter version of this paper was presented at WEB 2006, a pre-ICIS workshop on e-business, in Milwaukee, WI.  相似文献   
942.
This paper contextualises, describes and discusses a student project which takes a particular exploratory approach to using mathematical surface definition as a language and vehicle for co-rational design co-authorship for architecture and engineering. The project has two authors, one from an architectural and one from an engineering educational background. It investigates the metaphorical and operational role of mathematics in the design process and outcomes.  相似文献   
943.
In this paper, we use the UML MARTE profile to model high-performance embedded systems (HPES) in the GASPARD2 framework. We address the design correctness issue on the UML model by using the formal validation tools associated with synchronous languages, i.e., the SIGALI model checker, etc. This modeling and validation approach benefits from the advantages of UML as a standard, and from the number of validation tools built around synchronous languages. In our context, model transformations act as a bridge between UML and the chosen validation technologies. They are implemented according to a model-driven engineering approach. The modeling and validation are illustrated using the multimedia functionality of a new-generation cellular phone.  相似文献   
944.
A new fault detection and diagnosis approach is developed in this paper for a class of singular nonlinear systems via the use of adaptive updating rules. Both detection and diagnostic observers are established, where Lyapunov stability theory is used to obtain the required adaptive tuning rules for the estimation of the process faults. This has led to stable observation error systems for both fault detection and diagnosis. A simulated numerical example is included to demonstrate the use of the proposed approach and encouraging results have been obtained.  相似文献   
945.
In this paper, we present an interval model of networked control systems with time-varying sampling periods and time-varying network-induced delays and discuss the problem of stability of networked control systems using Lyapunov stability theory. A sufficient stability condition is obtained by solving a set of linear matrix inequalities. In the end, the illustrative example demonstrates the correctness and effectiveness of the proposed approach.  相似文献   
946.
This paper focuses on the design problem of a memoryless state feedback robust H-infinity controller for a class of uncertain neutral systems. By using a newly established integral inequality, a new delay-dependent bounded real lemma for such systems is derived without involving a fixed model transformation. Furthermore, new delay-dependent sufficient conditions for the existence of robust H-infinity controllers are presented in terms of nonlinear matrix inequalities. A design procedure involving an iterative algorithm is also proposed to design such controllers. Numerical examples are given to demonstrate the less conservatism of the proposed method.  相似文献   
947.
QuadCover - Surface Parameterization using Branched Coverings   总被引:4,自引:0,他引:4  
We introduce an algorithm for the automatic computation of global parameterizations on arbitrary simplicial 2-manifolds, whose parameter lines are guided by a given frame field, for example, by principal curvature frames. The parameter lines are globally continuous and allow a remeshing of the surface into quadrilaterals. The algorithm converts a given frame field into a single vector field on a branched covering of the 2-manifold and generates an integrable vector field by a Hodge decomposition on the covering space. Except for an optional smoothing and alignment of the initial frame field, the algorithm is fully automatic and generates high quality quadrilateral meshes.  相似文献   
948.
This paper presents a fairly complete treatment of stability and controllability of piecewise-linear systems defined on a conic partition of . This includes necessary and sufficient conditions for stability and controllability, as well as establishing that controllability implies stabilizability by piecewise-linear state feedback. A key tool in the approach is the study of the Poincaré map.  相似文献   
949.
950.
A Model-Based Method for an Online Diagnostic Knowledge-Based System   总被引:2,自引:0,他引:2  
Fault diagnosis is very important for modern production technology and has received increasing theoretical and practical attention during the last few years. This paper presents a model-based diagnostic method for industrial systems. An online, real-time, deep knowledge based fault detection system has been developed by combining different development environments and tools. The system diagnoses, predicts and compensates faults by coupling symbolic and numerical data in a new environment suitable for the interaction of different sources of knowledge and has been successfully implemented and tested on a real hydraulic system.  相似文献   
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