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1.
Many decision making problems which are complicated and fuzzy in nature exist in modern society. How to solve them is becoming increasingly important for human society. For solving multiple criteria's decision making in a fuzzy environment, in this paper, we will propose a new algorithm for evaluating naval tactical missile systems by the fuzzy Analytical Hierarchy Process based on grade value of membership function. Generally, we are given scores by experience of experts to represent judgmental objects. In this paper, from viewpoint of many experts, we will build membership functions of judgement criteria for all sub-items. When the membership function is built, we can calculate the grade value by data of missile performance. The grade value is called performance score. Our methods can be summarized in the following.
  • 1.1. Building membership function of judgement criteria for all sub-items, it is called fuzzy standard.
  • 2.2. Calculate the grade of membership function by practical data to represent performance scores.
  • 3.3. Use fuzzy AHP method and entropy concepts to calculate aggregate weights.
Finally, for a simple and efficient computation, we have developed a systematic and practical program to calculate all algorithms, and apply the new algorithm to a naval tactical missile systems valuation and selection problem.  相似文献   

2.
The first and major part of this presentation shows how OR education may be improved through the use of spreadsheets, with several examples:
  • •in decision theory, where the drawing capabilities of Excel are used to represent decision trees and where window switching and macros allow the educator to animate his presentation;
  • •in linear programming, where the solver is used (remarks are made relating to the adequacy of the solver's solutions), and where the spreadsheet's graphing capabilities are used both to represent the feasible set and the objective function, and to interactively animate the objective function or constraint movements;
  • •in dynamic programming, deterministic or stochastic, where it is shown that several standard spreadsheet functions facilitate the development of specialized models;
  • •in simulation, where it will be seen how stochastic simulation may be facilitated through the use of an add-in, and how a decision support system may thus be built from scratch in less than 10 minutes.
A creative use of the spreadsheet in business OR models is presented in the second part of this presentation, with an example in process simulation: airport luggage traffic simulation. A short third part presents the possibilities offered by spreadsheet add-ins.  相似文献   

3.
This paper explores the social theories implicit in system dynamics (SD) practice. Groupings of SD practice are observed in different parts of a framework for studying social theories. Most are seen to be located within `functionalist sociology'. To account for the remainder, two new forms of practice are discussed, each related to a different paradigm. Three competing conclusions are then offered:
  • 1.The implicit assumption that SD is grounded in functionalist sociology is correct and should be made explicit.
  • 2.Forrester's ideas operate at the level of method not social theory so SD, though not wedded to a particular social theoretic paradigm, can be re-crafted for use within different paradigms.
  • 3.SD is consistent with social theories which dissolve the individual/society divide by taking a dialectical, or feedback, stance. It can therefore bring a formal modelling approach to the `agency/structure' debate within social theory and so bring SD into the heart of social science.
The last conclusion is strongly recommended.  相似文献   

4.
The performance of an iron-bath reactor has been studied using a comprehensive numerical model that combines a computational fluid dynamics approach for the gas phase and a heat and mass balance model for the bath. The model calculates:
  • •coal, ore, flux and oxygen consumption;
  • •post-combustion ratio (PCR);
  • •heat-transfer efficiency (HTE);
  • •off-gas temperature and composition;
  • •heat transfer and chemical reactions between gas and iron and slag droplets; and
  • •heat transfer between gas and bath, refractories and lance.
The model was validated with data reported by the Nippon Steel Corporation for a 100 t pilot plant, and the calculated and measured data are in good agreement. Modelling results showed that the dominant mechanisms of heat transfer from the gas to the bath are radiation to the slag surface and convection heat transfer to droplets.  相似文献   

5.
Bidirected graphs generalize directed and undirected graphs in that edges are oriented locally at every node. The natural notion of the degree of a node that takes into account (local) orientations is that of net-degree. In this paper, we extend the following four topics from (un)directed graphs to bidirected graphs:
  • –Erdős–Gallai-type results: characterization of net-degree sequences,
  • –Havel–Hakimi-type results: complete sets of degree-preserving operations,
  • –Extremal degree sequences: characterization of uniquely realizable sequences, and
  • –Enumerative aspects: counting formulas for net-degree sequences.
To underline the similarities and differences to their (un)directed counterparts, we briefly survey the undirected setting and we give a thorough account for digraphs with an emphasis on the discrete geometry of degree sequences. In particular, we determine the tight and uniquely realizable degree sequences for directed graphs.  相似文献   

6.
In this paper, we set up a House of Profit Model, an approach of maximizing profit of a food retailing chain by targeting and promoting valuable customers. Our model combines
  • •segmentation analysis of households using Loyalty Card and Scanner Data,
  • •price and promotion elasticity analysis,
  • •simulation of effects of pricing and promotion,
  • •price and promotion optimization to maximize profit.
These components are well-known in the literature and each of them has received considerable independent study. However, in this study we combine each of these components into one consistent, application-orientated model. We then demonstrate using panel data that the combination has a synergic effect on the efficiency of estimation and the maximization of profit (e.g., price and promotion elasticity estimation is improved by conducting it within market segments rather than across an entire hetereogeneous population). These estimates are further improved by incorporating “pass through”—a functional relationship between a retailer’s unit prices and unit costs.  相似文献   

7.
An auto-sleep system is defined by the following two properties:
  • 1.(i) a call for the system occurs randomly and intermittently
  • 2.(ii) the system automatically goes to sleep if there occurs no call during a prespecified time T.
It considers four states:
  • 1.(a) sleep
  • 2.(b) warm-up
  • 3.(c) nonusage
  • 4.(d) usage.
For such a system, the time to sleep has been discussed based on suitable criteria. This study extends the model for an auto-sleep system so that the model can deal with multi-usage states. With a view to determining an optimal time to sleep under the extended model, the expected energy consumed per unit time is formulated as a criterion to be minimized. The existence of an optimal time to sleep is examined under a general call distribution. Numerical examples are also provided for a Weibull as well as a log-normal call distribution.  相似文献   

8.
This paper is devoted to the characterization of external electrostatic potentials for which the Vlasov-Poisson-Fokker-Planck system satisfies one of the following properties:
  • (i) the system admits stationary solutions,
  • (ii) any solution to the evolution problem converges to a stationary solution, or, equivalently, no mass vanishes for large times,
  • (iii) the free energy is bounded from below, We give conditions under which these different notions of confinement are equivalent.
  相似文献   

9.
《Historia Mathematica》2002,29(2):193-198
Analysis of the errors in two Old Babylonian “algebraic” problems shows
  • •that the computations were performed on a device where additive contributions were no longer identifiable once they had entered the computation;
  • •that this device must have been some kind of counting board or abacus where numbers were represented as collections of calculi;
  • •that units and tens were represented in distinct ways, perhaps by means of different calculi.
© 2002 Elsevier Science (USA).Eine Analyse der Rechenfehler in zwei altbabylonischen “algebraischen” Aufgaben läßt mehrere Rückschlüsse auf ein Hilfsmittel zu, das zur Durchführung von Rechnungen benutzt worden sein kann:
  • •Additive Beiträge waren nach ihrer Eintragung in die Rechnung nicht länger identifizierbar.
  • •Das Gerät war eine Art Rechenbrett, auf welchem Zahlen als Haufen von Rechensteinen erschienen.
  • •Einer und Zehner wurden in verschiedener Weise, evtl. mittels verschiedener Rechensteine repräsentiert.
© 2002 Elsevier Science (USA).MSC subject classification: 01A17.  相似文献   

10.
We prove the following theorems:
  • 1)Any surgery of index one on u tight contact manifold (of dimension three) gives rise to a manifold which carries a natural tight contact structure.
  • 2)In a tight contact manifold, any two isotopic spheres which carry the same characteristic foliation are isotopic through a contact isolopy.
  • 3)In a tight contact manifold, any two isotopic spheres have isomorphic complements.
  相似文献   

11.
We prove a full completeness theorem for multiplicative–additive linear logic (i.e. MALL) using a double gluing construction applied to Ehrhard’s *-autonomous category of hypercoherences. This is the first non-game-theoretic full completeness theorem for this fragment. Our main result is that every dinatural transformation between definable functors arises from the denotation of a cut-free MALL proof.Our proof consists of three steps. We show:
  • •Dinatural transformations on this category satisfy Joyal’s softness property for products and coproducts.
  • •Softness, together with multiplicative full completeness, guarantees that every dinatural transformation corresponds to a Girard MALL proof-structure.
  • •The proof-structure associated with any dinatural transformation is a MALL proof-net, hence a denotation of a proof. This last step involves a detailed study of cycles in additive proof-structures.
The second step is a completely general result, while the third step relies on the concrete structure of a double gluing construction over hypercoherences.  相似文献   

12.
The Brownian path {ω(s); 0 ⩽ st} is dissected and then reassembled in such a way that
  • (i) the last visit γt at the origin, as well as the fragment {ω(s); γtst}, are left invariant;
  • (ii) on [0, γt], local time becomes maximum-to-date and occupation time of|R+ becomes location of maximum; and
  • (iii) the resulting process is again Brownian.
Characterizations of conditional processes are employed to establish the result. Several consequences of the latter are discussed.  相似文献   

13.
This work deals with the modelling of a three-link manipulator mounted on a plane with a time-dependent inclination. Two cases are considered.
  • (i)The plane is part of a rigid body.
  • (ii)The plane is in a moored ship.
  相似文献   

14.
15.
16.
We consider the common-knowledge paradox raised by Halpern and Moses: common knowledge is necessary for agreement and coordination, but common knowledge is unattainable in the real world because of temporal imprecision. We discuss two solutions to this paradox:
  • 1.(1) modeling the world with a coarser granularity, and
  • 2.(2) relaxing the requirements for coordination.
  相似文献   

17.
Egress complexity is concerned with the summative uncertainty experienced by a naive occupant of a building when faced with a challenge to evacuate without the assistance of signage. This paper takes the present model of egress complexity and recasts its basic initiative in terms of elementary order theory. Arguments are presented to demonstrate
  • •the existence of distinct maximum and minimum exit complexities for a given number of compartments,
  • •the monotonic nature of complexity and
  • •the relationship of a given floorplan complexity to the corresponding measures of its homomorphic images
The uniqueness of the theory on which the model is developed stems from a scenario-independent nonmetric approach to egress measurement.  相似文献   

18.
The authors use their recently proved integral inequality to obtain bounds for the covariance of two random variables
  • 1.in a general setup and
  • 2.for a class of special joint distributions.
The same inequality is also used to estimate the difference of the expectations of two random variables. Finally, the authors study the attainability of a related inequality.  相似文献   

19.
In my talk, I will present some works done in the nineties on Laplacians on graphs: from eigenvalue problems to inverse problem for resistor networks. I will focus on the motivations and the main results as well as on the main ideas:
  • •A differential topology point of view on the minor relation: a nice stratification associated to a finite graph Γ whose strata are associated to the minors of Γ
  • •“Discrete” (graphs) versus “continuous” (Riemannian manifolds)
  • •Stability of spectra with respect to singular limits: a finite dimensional theory of operators with domains (Von Neumann theory).
The link with topology will appear in some results about my graph parameter μ, in particular the planarity and the linkless embedding properties.  相似文献   

20.
The paper studies equation (1.1) in two cases:
  • •(i)p ≡ 0,
  • •(ii)p ≠ 0.
In Case (i), the asymptotic stability of the solution x = 0 is studied; in Case (ii), the uniform boundedness and uniform ultimate boundedness of all solutions of (1.1) are proved.  相似文献   

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