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1.
A new set of conversions for derivations in the system of sequents for intuitionistic predicate logic will be defined. These conversions will be some modifications of Zucker's conversions from the system of sequents from [11], which will have the following characteristics: (1) these conversions will be sufficient for transforming a derivation into a cut-free one, and (2) in the natural deduction the image of each of these conversions will be either in the set of conversions for normalization procedure, or an identity of derivations. This will be used to give a new proof of the normalization theorem for natural deduction, as a consequence of the cut-elimination theorem for the system of sequents. Received: January 2003  相似文献   

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3.
The paper examines the long term problems of operational research through an analysis of OR as a system. The general environment will change as a result of the transformations occurring within the developed societies and of the mutations in the North-South relations; the interaction between OR, mass media and public opinion will be influenced by the emerging ideologies; the naive conceptions of the division of labour between policy makers and OR specialists will have to be revised as OR studies will be more and more developed for governments through national administrations, international organizations or public opinions; the formulation of goals will no longer be separated from the search for institutions liable to elaborate suitable goals; the tendency towards a systems analysis inspired by general systems theory should be reinforced; and finally the OR people will have to rethink the relations between their applied studies, the central core of OR itself and the various social sciences. Time seems to have come for an epistemology and a prospective study of OR.  相似文献   

4.
The problem of finding the singularities of monotone vectors fields on Hadamard manifolds will be considered and solved by extending the well-known proximal point algorithm. For monotone vector fields the algorithm will generate a well defined sequence, and for monotone vector fields with singularities it will converge to a singularity. It will also be shown how tools of convex analysis on Riemannian manifolds can solve non-convex constrained problems in Euclidean spaces. To illustrate this remarkable fact examples will be given.  相似文献   

5.
The concept of stability, originally introduced for polynomials, will be extended to apply to the class of entire functions. This generalization will be called Hurwitz stablility and the class of Hurwitz stable functions will serve as the main focus of this paper. A first theorem will show how, given a function of either of the Stieltjes classes, a Hurwitz stable function might be constructed. A second approach to constructing Hurwitz stable functions, based on using additional functions from the Laguerre-Pólya class, will be presented in a second theorem.  相似文献   

6.
The notion of exceptional family of elements for general order complementarity problems in Banach spaces will be introduced. It will be shown that for general order complementarity problems defined by completely continuous fields the problem has either a solution or an exceptional family of elements. Finite dimensional examples and an application to integral operators will be given.  相似文献   

7.
Logical relations occur frequently in integer programming problems and are modelled by introducing binary variables in association with linear expressions. Applications requiring constraints involving precedence, exclusion, implication and other conditions give rise to the logical relations OR and IMPLIES in the models. These relations will be considered in this paper from a modelling point of view and formulations investigated for situations where the logical variables link sets of integer variables. Valid inequalities (cuts) that can be added to a model will be developed for a number of the formulations and the computational benefits of these cuts will be considered from an experimental point of view by considering the performance of sets of problem instances. New formulations and combinations of older established formulations will be considered. It will be contended that tight formulations may not always be the most successful.  相似文献   

8.
A fuzzy-stochastic OWA model for robust multi-criteria decision making   总被引:3,自引:0,他引:3  
All realistic Multi-Criteria Decision Making (MCDM) problems face various kinds of uncertainty. Since the evaluations of alternatives with respect to the criteria are uncertain they will be assumed to have stochastic nature. To obtain the uncertain optimism degree of the decision maker fuzzy linguistic quantifiers will be used. Then a new approach for fuzzy-stochastic modeling of MCDM problems will be introduced by merging the stochastic and fuzzy approaches into the OWA operator. The results of the new approach, entitled FSOWA, give the expected value and the variance of the combined goodness measure for each alternative. Robust decision depends on the combined goodness measures of alternatives and also on the variations of these measures under uncertainty. In order to combine these two characteristics a composite goodness measure will be defined. The theoretical results will be illustrated in a watershed management problem. By using this measure will give more sensitive decisions to the stakeholders whose optimism degrees are different than that of the decision maker. FSOWA can be used for robust decision making on the competitive alternatives under uncertainty.  相似文献   

9.
A general approach for the solution of possibly discontinuous optimization problems by means of pointwise (perhaps smooth) approximations will be proposed. It will be proved that sequences generated by pointwise approximation techniques eventually satisfy well justified stopping criteria. Numerical examples will be given.  相似文献   

10.
In this paper, we will develop a numerical technique for finding the eigenvalues of fourth-order non-singular Sturm–Liouville problems. We used the variational iteration methods as a basis for this technique. Numerical results and conclusions will be presented. Comparison results with others will be presented.  相似文献   

11.
Götz Krummheuer 《ZDM》2003,35(6):247-256
Toulmin’s analysis of argumentation (1969) will be presented and exemplarily discussed within the theoretical frame of the emergence of an accounting practice in primary mathematics classrooms. With regard to more complex argumentations some modifications will be outlined. More general aspects of the “explanatory relevance” and “social force” of an argumentation will follow. Some perspectives for additional research will be suggested.  相似文献   

12.
In this paper, we will discuss the mixed boundary value problems for the second order elliptic equation with rapidly oscillating coefficients in perforated domains, and will present the higher-order multiscale asymptotic expansion of the solution for the problem, which will play an important role in the numerical computation . The convergence theorems and their rigorous proofs will be given. Finally a multiscale finite element method and some numerical results will be presented. This work is Supported by National Natural Science Foundation of China (grant # 10372108, # 90405016), and Special Funds for Major State Basic Research Projects( grant # TG2000067102)  相似文献   

13.
In this survey paper, the synchronization will be initially studied for infinite dimensional dynamical systems of partial differential equations instead of finite dimensional systems of ordinary differential equations,and will be connected with the control theory via boundary controls in a finite time interval. More precisely,various kinds of exact boundary synchronization and approximate boundary synchronization will be introduced and realized by means of fewer boundary controls for a coupled system of wave equations with Dirichlet boundary controls. Moreover, as necessary conditions for various kinds of approximate boundary synchronization, criteria of Kalman's type are obtained. Finally, some prospects will be given.  相似文献   

14.
It will be shown how plasma actuator can generate wall-jet-like flow or train of periodical vortices depending on the generator setting. For generation the high-frequency high-voltage AC is used. Low-frequency modulation of the supply voltage is required to generate vortices. Data acquisition will be performed using time-resolved PIV technique. Phase-averaging will be studied from two different perspectives. Firstly, sampling of phases will be ensured using trigger that is contained in the PIV software and, secondly, phase-averaged flow will be computed from two main modes of POD analysis. The generated flow patterns are to be applied for control of a boundary layer. (© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

15.
In this paper, a model which describes manpower planning procedures for a hierarchical system having certain desired properties to be achieved is presented. These properties will act as constraints on the system. It will be assumed that eventual, desired properties are achieved gradually over a period of time. Promotion policies will be wastagelinked and designed to satisfy vacancy-expansion demands. The model will be applied to data from a group of English County Police Constabularies.  相似文献   

16.
The continuously growing need for forestry products and the limited availability of forests have raised the question of how best the forest economy should be managed. In what follows, it will be assumed that a group of cellulose factories will be built in a forest region of a country, where the forest will be cultivated, solely with the needs of the factories in mind. Since large forestry machines will be used, a selective felling of tress will not be possible; a machine removes all the trees from an area being harvested. After that, new trees are planted immediately. This obviously necessitates the forest being divided into smaller subforests, which produce raw material for the factories in a sufficiently continuous manner. the optimal dimensioning of such a system of forests in the steady state is discussed. The basic difference from present practice is the assumption that the time needed for the transportation of wood is negligible; the cost aspect is not considered in this paper.  相似文献   

17.
A class of implicit finite difference schemes of the Beam and Warning approximate factorization type will be addressed. The development and analysis of various aspects of this class of schemes will be given along with the motivations behind many of the choices. Various acceleration and efficiency modifications such as matrix reduction, diagonalization and flux split schemes will be presented. The methods are demonstrated in fully vectorized codes for a CRAY type architecture. The emphasis will be on the Euler equations in generalized coordinates.  相似文献   

18.
In this paper the Bayesian approach for nonlinear multivariate calibration will be illustrated. This goal will be achieved by applying the Gibbs sampler to the rhinoceros data given by Clarke (1992, Biometrics, 48(4), 1081–1094). It will be shown that the point estimates obtained from the profile likelihoods and those calculated from the marginal posterior densities using improper priors will in most cases be similar.  相似文献   

19.
A generalized KdV equation with time-dependent coefficients will be studied. The BBM equation with time-dependent coefficients and linear damping term will also be examined. The wave soliton ansatz will be used to obtain soliton solutions for both equations. The conditions of existence of solitons are presented.  相似文献   

20.
In this paper metamorphosis problems for block designs will be presented and recent developments will be surveyed.  相似文献   

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