首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 281 毫秒
1.
The problem of crack path selection in piezoelectric bimaterials is considered in this paper. Based on the Stroh formulation for anisotropic material and Green’s functions for piezoelectric bimaterials, the crack problem is expressed in terms of coupled singular integral equations at first, and then the equations are used to solve for stress and electric displacement fields numerically. A crack impinging an interface joining two dissimilar materials may arrest or may advance by either penetrating the interface or deflecting into it. The competition between deflection and penetration is investigated using the maximum energy release rate criterion. Numerical results are presented to study the role of remote electroelastic loads on the path selection of crack extension.  相似文献   

2.
Choice of an adequate material in design process is one of the critical tasks for the relevant decision-makers. At this insight, the consistency of the decisions is extremely depending on the relevance of adapted techniques to the nature of different problem cases. This paper proposed an integrated decision aid (IDEA) to match the suitable techniques with different problem cases based on the following six dimensions: (i) the type of the decision problem, (ii) the size of the problem, (iii) selection of the preference techniques by decision-makers, (iv) decision-makers’ preference structure, (v) the necessity for the use of relative importance, (vi) the nature of performance values. Furthermore, the implementation procedure of the proposed IDEA for a material selection problem is demonstrated with the previously cited applications from material science literature. Hereafter, it is expected that the IDEA provides great advantages and encouragements to researchers/practitioners in order to prevent excessive time consuming, probable misapplications, and the other challenging issues in multiple criteria analysis of material selection problems.  相似文献   

3.
Using the Analytic Network Process (ANP), this article aims at presenting a new concept for multicriteria material selection by means of allowing feedback and interactions within and between sets of design criteria and alternatives. The approach and its advantages are discussed using a multicriteria material selection case study on non-metallic gears under multifunctional design requirements (thermal performance, mechanical performance, and weight). In particular, it is shown how the selection of material alternatives under different criteria can be viewed as a network problem, as opposed to a conventional hierarchical decision-making process. The effect of different weighting factors of criteria clusters on the final solution is also discussed.  相似文献   

4.
Ranking and choosing the best material is one of most important stages in material selection process. Using linear assignment method, the multi-criteria decision making (MCDM) approach is proposed in decision-making process to rank the materials for a given engineering component with respect to several criteria. The proposed material selection procedure is relatively simple, and can be a useful approach when material selection problem includes qualitative properties or user-interaction aspects. The suggested approach also can be use for quantitative properties. Three examples are included to demonstrate the suggested method. Result of proposed approach showed good agreement with other methods.  相似文献   

5.
In engineering design, the decision to select an optimal material for a particular product is a problem requiring multi-criteria decision analysis that involves both qualitative and quantitative factors. The evaluation of alternative materials may be based on imprecise information or uncertain data. Furthermore, there can be significant dependence and feedbacks between the different criteria for material selection. However, most existing decision approaches cannot capture these complex interrelationships. In response, this paper proposes a general framework for evaluating and selecting the best material for a given application. A novel hybrid multiple criteria decision making (MCDM) model combining DEMATEL-based ANP (DANP) and modified VIKOR is used to solve the material selection problems of multiple dimensions and criteria that are interdependent. Moreover, target-based criteria as well as cost and benefit criteria can be addressed simultaneously in the proposed model. Finally, an empirical case concerning the bush material selection for a split journal bearing is presented to illustrate the potential of the new model. The results show that the proposed method for material selection is effective and provides meaningful implications for designers and engineers to refer.  相似文献   

6.
In this paper a practical approach to design, based on the concept of selection, is presented. The approach involves: first, the generation of alternative concepts using ideation tecniques; second, the selection of the ‘most-likely-to-succeed’ concepts for further development into feasible alternatives; third, the formulation and solution of selection-decision-support problems to rank the feasible alternatives in order of preference using multiple attributes.The method presented in this paper is a combination of the methods proposed by Pugh and by Mistree and Muster. The former method is appropriate for use in concept selection, which is characterized by many alternatives and essentially insight-based ‘soft’ information. The latter method is appropriate when there are few alternatives and a mix of science-based ‘hard’ and insight-based ‘soft’ information. The method presented by Mistree and Muster is therefore used to formulate and solve the selection-decision-support problem. The design example used in this paper is a modified version of that used by Pugh.  相似文献   

7.
Materials play a key role during the entire product design and manufacturing phase as a wrongly selected material may often lead to premature product failure causing loss of revenue and repute of the concerned manufacturing organization. While selecting the most suitable material for a specific application, the designers often need a sound and systematic methodology to deal with this problem having multiple candidate alternative choices and conflicting objectives. Most of the previously applied methodologies for material selection have either adopted criteria weights estimated using subjective judgments of the designers or failed to give due emphasis on the voice of the customers to meet their requirements. In this paper, a maiden venture is taken to solve the material selection problems using a quality function deployment (QFD)-based approach that can integrate the voice of the customers for a product with its technical requirements. The applicability and solution accuracy of this QFD-based material selection model is demonstrated with the help of four illustrative examples. To ease out the materials selection decision-making process, a user-friendly software prototype in Visual BASIC 6.0 is also developed.  相似文献   

8.
包装印刷设计中印刷材料的选择问题   总被引:1,自引:1,他引:1  
杨祖彬 《包装工程》2006,27(1):256-258
针对目前在包装设计印刷材料的选择方面,只注重功能要求这个单一原则的现实问题,从包装印刷品的功能、环境特性、印刷效果3方面,探讨了包装印刷品设计中印刷材料的选择问题,包装印刷品印刷材料的选择主要涉及纸张等承印材料和油墨材料的选择.  相似文献   

9.
The aim of the current study is to implement a novel tool to help the decision-maker for selection of a proper material that will meet all the requirements of the design engineers. Preference selection index (PSI) method is a novel tool to select best alternative from given alternatives without deciding relative importance between attributes. In the present study, three different types of material selection problems are examined. A validation and consistency test of preference selection index method is performed in present work by comparing results of PSI method with published results of graph theory and matrix approach (GTMA), and technique for order preference by similarity to ideal solution (TOPSIS) method, respectively. The research has concluded that the PSI method is logical and more appropriate for the material selection problems.  相似文献   

10.
Material selection is a complex process, since the process includes many criteria, determination of criteria weight and the most important factor is that the selection of appropriate criterion. The last factor indicates that the criterion must be selected in a manner, such that the selection based upon the known material parameters and the requirements of the application. Therefore the material selection can be done using MCDM (Multi Criterion Decision Making) methods. Since the inputs provided by the decision maker in linguistic manner, there is a possible chance of getting incomplete problems. So in order to overcome the problem, the inputs could be provided as fuzzy numbers. Since fuzzy set represents the uncertainty in human perceptions. In this paper, VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje in Serbian, means Multicriteria Optimisation and Compromise Solution) has been used a MCDM tool for the selection of alternate material for instrument panel used in electric car and in order to evaluate this selection process in fuzzy environment, fuzzy based VIKOR is used. In addition to the fuzzy VIKOR method, the environmental impacts are also considered and compared for the four materials. The results achieved in both the assessment, showed that Polypropylene could be an alternate material for the instrument panel. The objective of this study is to develop a rational method to select the best material for an application based upon known material parameters and the requirements of the application.  相似文献   

11.
The selection of an optimal material for an engineering design from among two or more alternative materials on the basis of two or more attributes is a multiple attribute decision making (MADM) problem. The selection decisions are complex, as material selection is more challenging today. There is a need for simple, systematic, and logical methods or mathematical tools to guide decision makers in considering a number of selection attributes and their interrelations and in making right decisions. This paper proposes a novel MADM method for material selection for a considered design problem. The method considers the objective weights of importance of the attributes as well as the subjective preferences of the decision maker to decide the integrated weights of importance of the attributes. Furthermore, the method uses fuzzy logic to convert the qualitative attributes into the quantitative attributes. Three examples are presented to illustrate the potential of the proposed method.  相似文献   

12.
Process planning is the systematic determination of the detailed methods by which parts can be manufactured from raw material to finished product. In a real manufacturing environment, usually several different parts need to be manufactured in a single facility sharing constrained resources. The existence of alternative process plans for each part makes the selection of process plan a very important issue in manufacturing. The objectives in process plan selection might be imprecise and conflicting. In this paper, a fuzzy approach is used to deal quantitatively with the imprecision of the process plan selection problem. Each process plan is evaluated and its contribution to shopfloor performance is calculated using fuzzy set theory. A progressive refinement approach is used to first identify the set of process plans that maximize the contributions, and then consolidate the set to reduce the manufacturing resources needed.  相似文献   

13.
Flexible manufacturing system (FMS) is described as a set of computerised numerical controlled machines, input–output buffers interconnected by automated material handling devices. This paper develops a bi-objective operation allocation and material handling equipment selection problem in FMS with the aim of minimising the machine operation, material handling and machine setup costs and maximising the machine utilisation. The proposed model is solved by a modified chaotic ant swarm simulation based optimisation (CAS2O) while applying pre-selection and discrete recombination operators is surveyed a capable method to simulate different experiments of FMS problems. A test problem is selected from the literature to evaluate the performance of the proposed approach. The results validate the effectiveness of the proposed method to solve the FMS scheduling problem.  相似文献   

14.
This paper presents a review on selection problem of material handling equipment (MHE) and general equipment used in industry area. The issue on MHE is widely paid attention since MHE has contribution on material, good and product accomplishment. Few methods and softwares have been proposed and developed to select the most appropriate MHE for a complex selection problem. Today’s high diverisity of MHE categories and types influence the generation of many possible choices which leads to the complexity. In this paper, a further discussion in terms of MHE and equipment including three major points namely level of selection, the context of selection problem and the approaches are served to highlight the complex MHE selection according to the number of possible choices provided, to analyse the consideration for the problem context, and to reveal the superior method for complex MHE selection. Forty-two papers collected from the past study are presented asscociating each point of the discussion.  相似文献   

15.
A microcomputer-based, Turbo Prolog expert system for selection of industrial trucks is described. Details of the industrial truck information supporting the development of the expert system are provided. The structuring of this information into a usable knowledge base and design of the inference mechanism to specifically address the truck selection problem are overviewed. Implementation details are discussed and the use of various AI concepts as applied within the expert system is described. Advantages and limitations of the expert system are suggested.  相似文献   

16.
This paper develops and describes a systematic computer-assisted methodology for the selection of material handling equipment (MHE). A microcomputer based system called ADVISOR models the material handling equipment selection process and employs information on 77 of the most common equipment types used in material transport, positioning, unit formation, and storage. The system identifies the appropriate equipment type for an application in two stages. At the primary stage, potential equipment types are identified through the use of physical requirements of the material handling activities specified by users. Eligible equipment are ranked according to their normalized accumulated rating and placed in a candidate equipment list. After this, a second stage involving an economic analysis for each eligible equipment is performed. The evaluation criteria provided by ADVISOR include present worth (PW).equivalent uniform annual cost (EUAC), return on investment (ROI), and payback period(PP) methods. Through ADVISOR, the expert-like MHE selection system recommends a ranked set of equipment based on user input data. An example problem is given in the paper to demonstrate the use of the system.  相似文献   

17.
Selection of proper phase change material (PCM) plays an important role towards the development of a latent heat thermal energy storage system. Selection of the phase change material is a difficult and restrained task due to the immense number of different available materials having different characteristics. One has to select such PCM which will give the desired thermal performance at minimum cost. This study deals with two Multiple Attribute Decision-Making (MADM) methods to solve PCM selection problem. These two methods are technique for order preference by similarity to ideal solution (TOPSIS) method and fuzzy TOPSIS method that uses linguistic variable presentation and fuzzy operation. Both the methods use an analytic hierarchy process (AHP) method to determine weights of the criteria. TOPSIS and fuzzy TOPSIS methods are used to obtain final ranking. A problem to evaluate the best choice of PCM used in solar domestic hot water system is considered here to demonstrate the effectiveness and feasibility of the proposed model. Empirical results showed that the proposed methods are viable approaches in solving PCM selection problem. TOPSIS is suitable for the use of precise performance ratings while the fuzzy TOPSIS is a preferred technique when the performance ratings are vague and inaccurate.  相似文献   

18.
In engineering design, material alternatives evaluate according to different criteria depending on the objectives of the problem. Performance ratings for different criteria are measured by different units, but in the decision matrix in order to have a valid comparison all the elements must be dimensionless. However, a lot of normalization methods have been developed for cost and benefit criteria, not only there has not been enough attention for engineering design situations in which approaching the target values are desirable but also the available methods have shortcomings. A new version of VIKOR method, which covers all types of criteria with emphasize on compromise solution, is proposed in this paper. The proposed comprehensive version of VIKOR also overcomes the main error of traditional VIKOR by a simpler approach. Suggested method can enhance exactness of material selection results in different applications, especially in biomedical application where the implant materials should possess similar properties to those of human tissues. Five examples are included to illustrate and justify the suggested method.  相似文献   

19.
The only two possible directions for extremal selection of tabular data, including those used in measurement technology, are considered: selection of the closest lower and closest greater datum (table entry) relative to a computed value, with the table itself considered an elementary Dedekind structure. The results of the selection are interpreted as a “floor” and a “ceiling,” respectively, two concepts well known in discrete mathematics that even have their own computer symbols. A solution of the problem of integral optimization of the precision of a measurement device consisting of a sensor and normalizing amplifier is presented as an example.  相似文献   

20.
Material selection is a very fast growing multi-criteria decision-making (MCDM) problem involving a large number of factors influencing the selection process. Proper choice of material is a critical issue for the success and competitiveness of the manufacturing organizations in the global market. Selection of the most appropriate material for a particular engineering application is a time consuming and expensive process where several candidate materials available in the market are taken into consideration as the tentative alternatives. Although a large number of mathematical approaches is now available to evaluate, select and rank the alternative materials for a given engineering application, this paper explores the applicability and capability of two almost new MCDM methods, i.e. complex proportional assessment (COPRAS) and evaluation of mixed data (EVAMIX) methods for materials selection. These two methods are used to rank the alternative materials, for which several requirements are considered simultaneously. Two illustrative examples are cited which prove that these two MCDM methods can be effectively applied to solve the real time material selection problems. In each example, a list of all the possible choices from the best to the worst suitable materials is obtained which almost match with the rankings as derived by the past researchers.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号