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1.
Management Information Systems uncritically draws upon a number of disciplines for its theoretical framework. In doing so it has imported a host of ontological, epistemological and behavioral assumptions which have shaped the theories, technologies and practices of information system analysis, design and implementation. This has taken place without careful reflection upon the historical emergence of these assumptions or upon the context within which attempts are made to operationalize them. This paper argues that the Management Information Systems field is in need of researching itself. It proposes that through a combination of genealogical and ethnographic research methodologies, the historical emergence of theoretical constructs and the organizational context within which information systems operate should be critically examined. In the following analysis, the historical emergence of the “problem” as a generic construct in the Management Information System literature is examined and contrasted to the manner in which a group of manufacturing managers defined problems within their organizational context. A critical tension is revealed which suggests that information systems researchers, analysts and designers need to at least broaden their assumption about the nature of organizational reality, human behavior, information processing and problem solving.  相似文献   

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Based on Zubov's procedure for constructing a Liapunoy function and the solution of linear undetermined equations, the paper develops a method to determine a dynamical system, the stability or instability boundary of which is given as a closed form in the state space. It is shown that the results obtained can be applied to the synthesis of an asymptotically stable system or a finite time stable system.  相似文献   

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Discrete-time delayed standard neural network model and its application   总被引:4,自引:2,他引:4  
The research on the theory and application of artificial neural networks has achieved a great success over the past two decades. Recently, increasing attention has been paid to recurrent neural networks, which are rich in dynamics, highly parallelizable, and easily implementable with VLSI. Due to these attractive features, RNNs have widely been applied to system identification, control, optimization and associative memories[1]. Stability analysis, which is critical to any applications of R…  相似文献   

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The main contributions of this paper are twofold. On the one hand, the twin Diffie–Hellman (twin DH) problem proposed by Cash et?al. is extended to the n-Diffie–Hellman (n-DH) problem for an arbitrary integer n, and this new problem is shown to be at least as hard as the ordinary DH problem. Like the twin DH problem, the n-DH problem remains hard even in the presence of a decision oracle that recognizes solution to the problem. On the other hand, observe that the double-size key in the Cash et?al. twin DH-based encryption scheme can be replaced by two separated keys each for one entity that results in a 2-party encryption scheme which holds the same security feature as the original scheme but removes the key redundancy. This idea is further extended to an n-party case, which is also known as n-out-of-n encryption. As examples, a variant of ElGamal encryption and a variant of Boneh–Franklin IBE have been presented; both of them have proved to be chosen ciphertext attack secure under the computational DH assumption and the computational bilinear Diffie–Hellman assumption, respectively, in the random oracle model. The two schemes are efficient, due partially to the size of their ciphertext, which is independent to the value n.  相似文献   

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The Deutsch–Jozsa problem is one of the most basic ways to demonstrate the power of quantum computation. Consider a Boolean function f : {0, 1} n → {0, 1} and suppose we have a black-box to compute f. The Deutsch–Jozsa problem is to determine if f is constant (i.e. f(x) = const, x ? {0,1}nf(x) = hbox {const, } forall x in {0,1}^n) or if f is balanced (i.e. f(x) = 0 for exactly half the possible input strings x ? {0,1}nx in {0,1}^n) using as few calls to the black-box computing f as is possible, assuming f is guaranteed to be constant or balanced. Classically it appears that this requires at least 2 n−1 + 1 black-box calls in the worst case, but the well known quantum solution solves the problem with probability one in exactly one black-box call. It has been found that in some cases the algorithm can be de-quantised into an equivalent classical, deterministic solution. We explore the ability to extend this de-quantisation to further cases, and examine with more detail when de-quantisation is possible, both with respect to the Deutsch–Jozsa problem, as well as in more general cases.  相似文献   

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This paper proposes a new matrix product, namely, semi-tensor product. It is a generalization of the conventional matrix product. Meanwhile, it is also closely related to Kronecker (tensor) product of matrices. The purpose of introducing this product is twofold: (i) treat multi-dimensional data; (ii) treat nonlinear problems in a linear way. Then the computer and numerical methods can be easily used for solving nonlinear problems. Properties and formulas are deduced. As an application, the Morgen’s problem for control systems is formulated as a numerically solvable problem.  相似文献   

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Consider a resource allocation problem on the following system. A system consists of m identical parallel machines and is alive only when all the machines are alive. To keep a machine alive, it requires resources (material, fuel, etc.). Resources with various sizes arrive one by one and the goal is to keep the system alive as long as possible. The problem has applications in many areas such as sequencing of maintenance actions for modular gas turbine aircraft engines[1]. Using scheduling term…  相似文献   

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In this paper, we address a university-timetabling problem and present a methodology that relies on Benders’ partitioning for its solution. This partitioning results from the special nature of the underlying integer programming formulation for this problem. We have used our methodology to schedule courses offered by the College of Engineering as well as to those offered university-wide at Virginia Tech. The results clearly depict an improvement in the quality of course schedules obtained by our methodology over those currently used, when the performance of a timetable is measured by the total distance traveled by the faculty members from their offices in respective departments to the classrooms, where the courses are offered.  相似文献   

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This paper considers the resource-constrained activity insertion problem with minimum and maximum time lags. The problem involves inserting a single activity in a partial schedule while preserving its structure represented through resource flow networks and minimizing the makespan increase caused by the insertion. In the general case, we show that finding a feasible insertion that minimizes the project duration is NP-hard. When only minimum time lags are considered and when activity durations are strictly positive, we show that the problem is polynomially solvable, generalizing previously established results on activity insertion for the standard resource-constrained project scheduling problem.  相似文献   

16.
《Applied Soft Computing》2008,8(2):985-995
The fuzzy min–max (FMM) network is a supervised neural network classifier that forms hyperboxes for classification and prediction. In this paper, we propose modifications to FMM in an attempt to improve its classification performance when a small number of large hyperboxes are formed in the network. Given a new input pattern, in addition to measuring the fuzzy membership function of the input pattern to the hyperboxes formed in FMM, an Euclidean distance measure is introduced for predicting the target class associated with the new input pattern. A rule extraction algorithm is also embedded into the modified FMM network. A confidence factor is calculated for each FMM hyperbox, and a user-defined threshold is used to prune the hyperboxes with low confidence factors. Fuzzy ifthen rules are then extracted from the pruned network. The benefits of the proposed modifications are twofold, viz., to improve the performance of FMM when large hyperboxes are formed in the network; to facilitate the extraction of a compact rule set from FMM to justify its predictions. To assess the effectiveness of modified FMM, two benchmark pattern classification problems are experimented, and the results from different methods published in the literature are compared. In addition, a fault detection and classification problem with a set of real sensor measurements collected from a power generation plant is evaluated using modified FMM. The results obtained are analyzed and explained, and implications of the modified FMM network as a useful fault detection and classification tool in real environments are discussed.  相似文献   

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This paper analyses the Japan Problem in science and technology from the viewpoint of the cultural factors involved. The selective use of contrary images of society depending on social context gives rise to a self-amplification of the problem. The paper critically examines what such generating mechanisms imply for a linear model connecting scientific, technological and economic performances. By focusing on the Science and Technology Basic Law and Plan approved in Japan in 1995 and 1996, it argues that measures taken for the promotion of basic research and creativity without giving due consideration to the relevant cultural factors provide an unsound basis for evaluating basic research. The paper argues that self-organisation by self-reference could provide an important general principle for human-centred science and technology policy, and especially policy for basic research.With Senior Associate Membership of St Antony's College, University of Oxford, UK for 1998–1999  相似文献   

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A Hamilton–Jacobi–Bellman Quasi-Variational Inequality (HJBQVI) for a river environmental restoration problem with wise-use of sediment is formulated and its mathematical properties are analyzed. A finite difference scheme with a penalization technique is then established for solving the HJBQVI. The scheme is free from any iterative solvers and is unconditionally stable and convergent in the viscosity sense under certain conditions. A demonstrative application example of the HJBQVI is finally presented.  相似文献   

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