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Based on several years of experience, the procedural aspects of the use of a comprehensive LP-model for community energy planning is discussed. The community energy system is seen as a technically complex, open system which is managed by a network of organizations (esoteric boxes). Technical complexity, closure and lack of unique management raises specific procedural problems for which solutions are suggested. The network management gives the comprehensive model a special rôle in the planning process in providing for improved information flows and conflict resolution. The viability of the paradigm of learning is noted. A methodology to merge substantive and procedural aspects is proposed.  相似文献   

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Volker Krase  Dieter Dinkler 《PAMM》2005,5(1):305-306
The mechanical behaviour of municipal solid waste is very complex due to the internal structure and differs considerably from ordinary materials. The fundamental idea of the presented mechanical constitutive model is the split of the material into two solid phases, justified by experimental observations, where fibrous particles signi.cantly influence the composite behaviour. Constitutive laws are independently introduced for each phase. A .nite deformation theory is applied, whereas the concept of elastoplasticity allows reproducing the highly non-linear stress-strain relations. A creep law describes time-depending deformation under compression loads. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

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This paper models the locations of landfills and transfer stations and simultaneously determines the sizes of the landfills that are to be established. The model is formulated as a bi-objective mixed integer optimization problem, in which one objective is the usual cost-minimization, while the other minimizes pollution. As a matter of fact, pollution is dealt with a two-pronged approach: on the one hand, the model includes constraints that enforce legislated limits on pollution, while one of the objective functions attempts to minimize pollution effects, even though solutions may formally satisfy the letter of the law. The model is formulated and solved for the data of a region in Chile. Computational results for a variety of parameter choices are provided. These results are expected to aid decision makers in the choice of excluding and choosing sites for solid waste facilities.  相似文献   

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This paper describes part of an on-going research project studying the issues of the application of Multicriteria Decision Aid Methodologies in real case-studies at the local level of the Portuguese Public Administration.In a first part, it address the complexity of decision situations in municipal management in general and the significance of decision analysis, namely multicriteria evaluation procedures, in conducting decision aid processes in that environment (Section 1).In a second part, a case study is described (Section 2), followed by its discussion in the ‘space of the weights’ in the context of different particular types of possible problem formulations (Section 3). For this purpose, an extension of Triangular Decision Technique is first proposed, followed by the presentation of a new Outranking approach, designated by ‘Outweigh’ analysis, which will permit the enrichment of the discussion.  相似文献   

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A double-sided dual-uncertainty-based chance-constrained programming (DDCCP) model was developed for supporting municipal solid waste management under uncertainty. The model was capable of tackling left-hand- and right-hand-side variables in constraints where those variables were affected by dual uncertainties (i.e. e.g. both fuzziness and randomness); and they were expressed as fuzzy random variables (FRVs). In this study, DDCCP model were formulated and solved based on stochastic and fuzzy chance-constrained programming techniques, leading to optimal solutions under different levels of constraints violation and satisfaction reliabilities. A long-term solid waste management problem was used to demonstrate the feasibility and applicability of DDCCP model. The obtained results indicated that DDCCP was effective in handling constraints with FRVs through satisfying them at a series of allowable levels, generating various solutions that facilitated evaluation of trade-offs between system economy and reliability. The proposed model could help decision makers establish cost-effective waste-flow allocation patterns under complex uncertainties, and gain in-depth insights into the municipal solid waste management system.  相似文献   

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A library of local search heuristics for the vehicle routing problem   总被引:1,自引:0,他引:1  
The vehicle routing problem (VRP) is a difficult and well-studied combinatorial optimization problem. Real-world instances of the VRP can contain hundreds and even thousands of customer locations and can involve many complicating constraints, necessitating the use of heuristic methods. We present a software library of local search heuristics that allows one to quickly generate solutions to VRP instances. The code has a logical, object-oriented design and uses efficient data structures to store and modify solutions. The core of the library is the implementation of seven local search operators that share a similar interface and are designed to be extended to handle additional options with minimal code change. The code is well-documented, straightforward to compile, and is freely available online. The code contains several applications that can be used to generate solutions to the capacitated VRP. Computational results indicate that these applications are able to generate solutions that are within about one percent of the best-known solution on benchmark problems.  相似文献   

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各地区城市市政工程情况统计分析及评估   总被引:2,自引:0,他引:2  
本文利用数学计算软件SAS作主成分分析 ,将我国各地区城市市政工程情况进行排序、分类 ,再用对应分析法分别对各地区进行单项指标分析 ,最后对影响各地区城市市政工程情况的几个重要因素进行相关分析。以期为各地区城市市政工程的健康发展提供更好的思路  相似文献   

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This paper initiates the work pertaining to the preparation of a library of MATLAB functions. This library involves programs for personal computers, which realize methods and algorithms for solving spectral problems for polynomial one-parameter matrices, as well as some spectral problems for two-parameter polynomial matrices. Bibliography:4 titles. Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 219, 1994, pp. 53–80. Translated by N. B. Lebedinskaya.  相似文献   

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Up to 2002, Hellenic Solid Waste Management (SWM) policy specified that each of the country’s 54 prefectural governments plan its own SWM system. After 2002, this authority was shifted to the country’s 13 regions entirely. In this paper, we compare and contrast regional and prefectural SWM planning in Central Macedonia. To design the prefectural plan, we assume that each prefecture must be self-sufficient, and we locate waste facilities in each prefecture. In contrast, in the regional plan, we assume cooperation between prefectures and locate waste facilities to serve the entire region. We present a new multicriteria mixed-integer linear programming model to solve the location–allocation problem for municipal SWM at the regional level. We apply the lexicographic minimax approach to obtain a “fair” nondominated solution, a solution with all normalized objectives as equal to one another as possible. A solution to the model consists of locations and technologies for transfer stations, material recovery facilities, incinerators and sanitary landfills, as well as the waste flow between these locations.  相似文献   

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The Continuous Convex Separable Quadratic Knapsack problem (CQKnP) is an easy but useful model that has very many different applications. Although the problem can be solved quickly, it must typically be solved very many times within approaches to (much) more difficult models; hence an efficient solution approach is required. We present and discuss a small open-source library for its solution that we have recently developed and distributed.  相似文献   

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The linear ordering problem consists of finding an acyclic tournament in a complete weighted digraph of maximum weight. It is one of the classical NP-hard combinatorial optimization problems. This paper surveys a collection of heuristics and metaheuristic algorithms for finding near-optimal solutions and reports about extensive computational experiments with them. We also present the new benchmark library LOLIB which includes all instances previously used for this problem as well as new ones.  相似文献   

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Parallel computing is now an essential paradigm for high performance scientific computing. Most existing hardware and software solutions are expensive or difficult to use. We developed Playdoh, a Python library for distributing computations across the free computing units available in a small network of multicore computers. Playdoh supports independent and loosely coupled parallel problems such as global optimisations, Monte Carlo simulations and numerical integration of partial differential equations. It is designed to be lightweight and easy to use and should be of interest to scientists wanting to turn their lab computers into a small cluster at no cost.  相似文献   

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Most of today's city managers are concerned about municipal financial problems. In trying to resolve these problems, scientific planning tools are needed to examine the optimality of resource allocation. For the municipal financial policy planners, the following two points are important.
  • 1.(1) Statistical aspects. Since there are many economic variables in municipal financial problems, it is necessary to clarify the relationship among these variables and to infer the parameters through a statistical approach.
  • 2.(2) Mathematical aspects. Policy-planners must specify the optimal value of these variables so as to attain the multiple goals of a local government.
Econometric models, especially the simultaneous equations approach, are appropriate for statistical analysis; whereas a goal-programming formulation may be used for mathematical aspects of the problem.In this paper, we propose and show that these two models can be combined. We call this the GPE model.The GPE model is applied to Urawa City. The Urawa model is composed of 6 structural equations 9 variables and 4 scenarios from the standpoint of future insight of Urawa City.From the Urawa Case, we conclude that the GPE model may be a practical tool for the municipal financial planning of other local governments.  相似文献   

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