材料对手机概念设计多样性的影响

随着材料科学和工程的发展,新的材料不断涌现,恰当地运用材料可以实现产品概念设计中的创新。本文从材料这一角度,以手机概念设计为实例,探讨由于产品材料、材料工艺的不同而导致的产品概念设计步骤多样化和产品设计结果的多样化,为设计师掌握材料信息、运用材料进行设计并实现产品概念设计的多样性提供参考方法和意见。     

Selection of non-traditional machining processes using analytic network process

Non-traditional machining (NTM) processes are now being widely used to generate intricate and accurate shapes in materials, like titanium, stainless steel, high strength temperature resistant (HSTR) alloys, fiber-reinforced composites, ceramics, refractories and other difficult-to-machine alloys having higher strength, hardness, toughness and other diverse material properties. Generation of complex shapes in such materials by the traditional machining processes is experienced to be difficult. For effective utilization of the capabilities of different NTM processes, careful selection of the most suitable process for a given machining application is often required. Selection of the best suited NTM process for a work material and shape feature combination requires the consideration of several criteria. In this paper, an analytic network process (ANP)-based approach is proposed to select the most appropriate NTM process for a given machining application taking into account the interdependency and feedback relationships among various criteria affecting the NTM process selection decision. To avoid the difficult and time consuming mathematical calculations of the ANP, a computer program is also developed in Visual Basic 6.0 with graphical user interface to automate the entire NTM selection decision process. It simply acts as an ANP solver. The observed results from the ANP solver are quite satisfactory and match well with those obtained by the past researchers.     

Evaluation of connection types in design for disassembly (DFD) using analytic network process

Design for disassembly (DFD) is an important design concept to make products more friendly for maintenance and remanufacturing practices. One of the important issues in DFD guidelines is related with the selection of the connectors used in the product. This paper evaluates the alternative connection types using the powerful analytic network process (ANP). The paper generates a complete ANP model, which includes all important aspects of connector selection. The model presented evaluates alternative connectors by including the three main concerns: (1) making product disassembly friendly; (2) making product assembly efficient; and (3) increasing the product performance when it is in-use. The results obtained from the model can benefit designers in making better decisions on selecting connectors to be used in the product. Benefits of the approach is detailed through illustrative example.     

An interval-valued intuitionistic fuzzy MABAC approach for material selection with incomplete weight information

In engineering design, selecting the most suitable material for a particular product is a typical multiple criteria decision making (MCDM) problem, which generally involves several feasible alternatives and conflicting criteria. In this paper, we aim to propose a novel approach based on interval-valued intuitionistic fuzzy sets (IVIFSs) and multi-attributive border approximation area comparison (MABAC) for handling material selection problems with incomplete weight information. First, individual evaluations of experts concerning each alternative are aggregated to construct the group interval-valued intuitionistic fuzzy (IVIF) decision matrix. Consider the situation where the criteria weight information is partially known, a linear programming model is established for determining the criteria weights. Then, an extended MABAC method within the IVIF environment is developed to rank and select the best material. Finally, two application examples are provided to demonstrate the applicability and effectiveness of the proposed IVIF-MABAC approach. The results suggest that for the automotive instrument panel, polypropylene is the best, for the hip prosthesis, Co–Cr alloys-wrought alloy is the optimal option. Finally, based on the results, comparisons between the IVIF-MABAC and other relevant representative methods are presented. It is observed that the obtained rankings of the alternative materials are good agreement with those derived by the past researchers.     

Literature review of reuse in business process modeling

Business process models play an important role in the analysis and improvement of the performance of an enterprise. Evidently, the quality of a business process model has a direct effect on the business performance. This evidence has motivated both the academic and industrial communities to look for suitable methods for creating good quality business process models. In particular, there is a wide agreement that reuse can accelerate the design process and produce high quality solutions by adopting best practices and agreed-up-on solutions. However, faced with various types of reusable artifacts, business process designers need a set of criteria to determine which type would suit best their needs and design context. To assist designers in their choice, we first present a set of criteria influencing the design phase in terms of effort required and the quality of the resulting model. Secondly, we use this set of criteria to present a state of the art on the most significant reusable design artifacts.     

Attribute based specification,comparison and selection of electroplating system using MADM approach

The problem of electroplating selection has been of concern to users for many years. The selection process is becoming more and more difficult due to the availability of large variety of electroplating configurations and manufacturing plants/products. The methods proposed so far consider only physical parameters (thickness, hardness, adhesion, etc.). In order to have precise information about the selection process, the performance of electroplating plays a vital role.The objective of this paper is to propose a methodology by which selection of electroplating product/plant can be made easy. This selection procedure will help the user to select the system most suited for his operational needs. Moreover, the paper discusses how the electroplating suppliers, designers and maintenance personnel will also be benefited.The identification and codification of attributes based on n-digit alpha numeric code is presented here. The 3 stage selection procedure allows rapid convergence from a very large number of options to manageable shortlist of potentially suitable electroplating option using ‘elimination search’ based on a few pertinent attributes. Then the selection procedure ranks them by employing a multiple attributes decision making (MADM) method using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) approach. It helps the decision maker(s) to organize the problem to be solved, and carry out analysis, comparisons and ranking of the alternatives. Magnitudes of different attributes are used to generate parameters of the hypothetical ideal electroplating, with all the candidate electroplating compared and ranked. This ranking gives the best available electroplating for particular application. The methodology is presented with the help of illustrated example of gold plating, which shows that it can benefit the designers, users or manufacturers.     

Optimal Materials Selection for Bimaterial Piezoelectric Microactuators

Piezoelectric actuation is one of the commonly employed actuation schemes in microsystems. This paper focuses on identifying and ranking promising active material/substrate combinations for bimaterial piezoelectric (BPE) microactuators based on their performance. The mechanics of BPE structures following simple beam theory assumptions available in the literature are applied to evolve critical performance metrics which govern the materials selection process. Contours of equal performance are plotted in the domain of the governing piezoelectric material properties (coefficients, elastic modulus, coupling factors and dielectric constants) for commonly employed substrates to identify optimal material combinations for various functional requirements. The influence of materials selection on the actuation efficiency, quality factor and the electromechanical impedance is also discussed. Selection of a suitable actuation mechanism for a boundary layer flow control application is illustrated by comparing the performance limits of BPE and bimaterial electrothermal actuators considering the constraints on the functional requirements imposed by the associated microfabrication routes.     

倾跌试验方法的优劣性分析

倾跌试验有多种方法,为了方便快捷地选取适用而有效的方法,本文就如何根据产品的不同外形、不同结构、不同电气性能选用适当的倾跌试验方法进行了具体分析。以便我们在工作中更准确更有效地选用。     

A comparison between Fuzzy AHP and Fuzzy TOPSIS methods to supplier selection

Supplier selection has become a very critical activity to the performance of organizations and supply chains. Studies presented in the literature propose the use of the methods Fuzzy TOPSIS (Fuzzy Technique for Order of Preference by Similarity to Ideal Solution) and Fuzzy AHP (Fuzzy Analytic Hierarchy Process) to aid the supplier selection decision process. However, there are no comparative studies of these two methods when applied to the problem of supplier selection. Thus, this paper presents a comparative analysis of these two methods in the context of supplier selection decision making. The comparison was made based on the factors: adequacy to changes of alternatives or criteria; agility in the decision process; computational complexity; adequacy to support group decision making; the number of alternative suppliers and criteria; and modeling of uncertainty. As an illustrative example, both methods were applied to the selection of suppliers of a company in the automotive production chain. In addition, computational tests were performed considering several scenarios of supplier selection. The results have shown that both methods are suitable for the problem of supplier selection, particularly to supporting group decision making and modeling of uncertainty. However, the comparative analysis has shown that the Fuzzy TOPSIS method is better suited to the problem of supplier selection in regard to changes of alternatives and criteria, agility and number of criteria and alternative suppliers. Thus, this comparative study contributes to helping researchers and practitioners to choose more effective approaches for supplier selection. Suggestions of further work are also proposed so as to make these methods more adequate to the problem of supplier selection.     

Simultaneous optimal selection of design and manufacturing tolerances with alternative manufacturing process selection

Tolerance specification is an important part of mechanical design. Design tolerances strongly influence the functional performance and manufacturing cost of a mechanical product. Tighter tolerances normally produce superior components, better performing mechanical systems and good assemblability with assured exchangeability at the assembly line. However, unnecessarily tight tolerances lead to excessive manufacturing costs for a given application. The balancing of performance and manufacturing cost through identification of optimal design tolerances is a major concern in modern design. Traditionally, design tolerances are specified based on the designer’s experience. Computer-aided (or software-based) tolerance synthesis and alternative manufacturing process selection programs allow a designer to verify the relations between all design tolerances to produce a consistent and feasible design. In this paper, a general new methodology using intelligent algorithms viz., Elitist Non-dominated Sorting Genetic Algorithm (NSGA-II) and Multi Objective Particle Swarm Optimization (MOPSO) for simultaneous optimal selection of design and manufacturing tolerances with alternative manufacturing process selection is presented. The problem has a multi-criterion character in which 3 objective functions, 3 constraints and 5 variables are considered. The average fitness factor method and normalized weighted objective functions method are separately used to select the best optimal solution from Pareto optimal fronts. Two multi-objective performance measures namely solution spread measure and ratio of non-dominated individuals are used to evaluate the strength of Pareto optimal fronts. Two more multi-objective performance measures namely optimiser overhead and algorithm effort are used to find the computational effort of NSGA-II and MOPSO algorithms. The Pareto optimal fronts and results obtained from various techniques are compared and analysed.     

试论现代首饰创意构思方法

创意构思是现代首饰设计的核心部分。设计者孜孜不倦进行各种尝试,以求作品的新突破。文章通过实例,试着从四个角度对首饰的创意构思方法展开论述。主题发散构思,通过选取主题,制作情绪版与规格版,提炼设计要素进行创作;模型辅助造型,通过制作三维模型,辅助设计者构思,调动设计者多方位感官进行创作;结构改变创新,通过首饰的组合型与可变性探索,寻找首饰设计的新视角;材料工艺综合利用,通过对传统、新兴材料的研究,突出材料特质,扩展首饰设计空间。     

Single-sided piercing riveting for adhesive bonding in vehicle body assembly

With increasing use of advanced high strength, lightweight materials and alternative vehicle architectures, materials joining issues have become increasingly important in automotive vehicle body assembly. Among the various joining methods, adhesive bonding is one of the important techniques for joining dissimilar materials in vehicle body assembly. During curing of the adhesive, it is necessary to fix and control the gap between the sheet panels to ensure the bonding strength and geometric quality. In this paper, a novel process, the single-sided piercing riveting (SSPR), is proposed for fixing and controlling the gap between the sheet panels during adhesive bonding of vehicle body assembly. The SSPR is a cold forming process for joining two or more sheet parts by driving a specifically designed U-shaped rivet using an impact force. The SSPR process is easy and convenient to implement without the need of a direct back support, and can meet the limited space requirement of vehicle body assembly. Joining experiments and performance tests were carried out to validate the effectiveness of the SSPR process. Performance comparison with other joining methods shows that mechanical properties of the lap-shear SSPR-bonded joints are superior to that of the SPR and SPR-bonded lap-shear joints.     

A comparative study of exchange and aggregation models in the B2B e-marketplace

This research seeks to provide an economic framework for understanding two major forms of e-marketplaces: aggregation-oriented vs. exchange-oriented e-marketplaces. By analyzing the marginal benefit per transaction in alternative models, we are able to determine the most suitable B2B e-marketplace for a wide variety of product categories, market conditions, and procurement methods. For example, when companies sell commodities in a fragmented market, the aggregation model is suitable for spot purchasing, and the exchange model works best for systematic purchasing. In addition, the effect of supplier consolidation and information technology-enabled cost reduction on model selection is discussed.     

Material Selection for Optimal Design of Thermally Actuated Pneumatic and Phase Change Microactuators

This paper discusses a methodology to select materials which deliver the best performance for thermally actuated pneumatic and phase change microactuators. The material selection is based on performance metrics estimated using simple closed form solutions for classical linear elastic theory for axisymmetric plates/membranes and lumped heat capacity thermal models. Although the elastic moduli of the diaphragm materials dictate the volume expansion for a given temperature rise, their influence on the achievable pressure difference is much less. It is found that engineering polymers are most suitable for thermopneumatically actuated diaphragms for delivering large displacements and work for the achievable pressures at frequencies of a few hundreds of Hertz. The membrane stresses due to in-plane pre-tension are found to have an adverse effect on the actuator performance. The material issues which constrain the performance limits of phase change actuators are also assessed, and the promising characteristics of paraffin waxes for microsystem applications are discussed.     

Adaptive strategy selection in differential evolution for numerical optimization: An empirical study

Differential evolution (DE) is a versatile and efficient evolutionary algorithm for global numerical optimization, which has been widely used in different application fields. However, different strategies have been proposed for the generation of new solutions, and the selection of which of them should be applied is critical for the DE performance, besides being problem-dependent. In this paper, we present two DE variants with adaptive strategy selection: two different techniques, namely Probability Matching and Adaptive Pursuit, are employed in DE to autonomously select the most suitable strategy while solving the problem, according to their recent impact on the optimization process. For the measurement of this impact, four credit assignment methods are assessed, which update the known performance of each strategy in different ways, based on the relative fitness improvement achieved by its recent applications. The performance of the analyzed approaches is evaluated on 22 benchmark functions. Experimental results confirm that they are able to adaptively choose the most suitable strategy for a specific problem in an efficient way. Compared with other state-of-the-art DE variants, better results are obtained on most of the functions in terms of quality of the final solutions and convergence speed.     

A rule-based expert system approach to process selection for cast components

A knowledge-based expert system at the discretion of casting product designers can be employed as a real-time expert advisor to assist product designers to achieve the correct casting design and select the most appropriate casting process for a given component. This paper proposes a rule-based expert system approach for casting process selection, and describes an ongoing rule prototype development. The system in its present development state consists of five interconnected levels each concerning a particular process selection parameter or group of parameters including alloy to be cast, casting geometric features, casting accuracy, production quantity and overall comparative costs. The system progressively evaluates the user's specifications against the capabilities of various casting processes and in each level selects the processes that satisfy the design parameters specified. The final comparative cost level compares the processes that have satisfied all the criteria in the previous levels and recommends the most economical option.     

Applying a selection method to choose Quality Attribute Techniques

ContextSoftware products have requirements on software quality attributes such as safety and performance. Development teams use various specific techniques to achieve these quality requirements. We call these “Quality Attribute Techniques” (QATs). QATs are used to identify, analyse and control potential product quality problems. Although QATs are widely used in practice, there is no systematic approach to represent, select, and integrate them in existing approaches to software process modelling and tailoring.ObjectiveThis research aims to provide a systematic approach to better select and integrate QATs into tailored software process models for projects that develop products with specific product quality requirements.MethodA selection method is developed to support the choice of appropriate techniques for any quality attribute, across the lifecycle. The selection method is based on three perspectives: (1) risk management; (2) process integration; and (3) cost/benefit using Analytic Hierarchy Process (AHP). An industry case study is used to validate the feasibility and effectiveness of applying the selection method.ResultsThe case study demonstrates that the selection method provides a more methodological and effective approach to choose QATs for projects that target a specific quality attribute, compared to the ad hoc selection performed by development teams.ConclusionThe proposed selection method can be used to systematically choose QATs for projects to target specific product qualities throughout the software development lifecycle.     

Cycles and Diamonds: How Management Consultants Diverge and Converge in Organization Design Processes

Divergence and convergence are both important elements of organizational design processes. This is often stated in the normative design literature, but it has hardly been studied empirically. How do designers of organizations diverge and converge in practice? Do they first develop alternatives and then choose the best one? Do they go through one or more successive cycles? And what makes them choose a certain route? In an in‐depth study of management consulting, we identified five different routes for diverging and converging in practice: one route for simple situations and four routes for complex situations. These routes differ in their sequence of activities, in their use of alternative solutions, and in their focus on content or on politics. It is shown that most design processes appear diamond‐shaped, with a divergent and a convergent side, but that these diamonds are often coloured or even fake, especially in socio‐politically complex situations. Pseudo‐divergence, i.e., the process of apparent divergence in public, is widespread.     

An investigation of dielectric material selection of RF-MEMS switches using Ashby’s methodology for RF applications

This paper presents a dielectric material selection methodology for RF-MEMS switch used for radio frequency applications. Here Ashby’s material selection approach is used to optimize the performance indices of RF-MEMS switch such as dielectric charging, stability, hold down voltage and RF performance. In this work, dielectric constant (ɛ _r), electrical resistivity (ρ), thermal conductivity (λ), thermal expansion coefficient (α), Young’s Modulus (E) are chosen as material indices of dielectric layer in RF-MEMS switch to evaluate the various performance indices. The Ashby’s material selection charts shows that Al₂O₃ and SiN are the best suitable material for dielectric layer in RF-MEMS switches to exhibit improved performance for radio frequency applications.

     

Personnel selection based on computing with words and fuzzy MULTIMOORA

Personnel selection process is aimed at choosing the best candidate to fill the defined vacancy in a company. It determines the input quality of personnel and thus plays an important role in human resource management. Given the uncertain, ambiguous, and vague nature of personnel selection process, it requires the application of multi-criteria decision making (MCDM) methods for robust recruitment. This paper hence is aimed at extending the fuzzy MULTIMOORA for linguistic reasoning under group decision making. The fuzzy MULTIMOORA was further modified in this study. The fuzzy MULTIMOORA for group decision making (MULTIMOORA–FG) enables to aggregate subjective assessments of the decision-makers and thus offer an opportunity to perform more robust personnel selection procedures. A personnel selection problem illustrated the group decision-making procedure according to MULTIMOORA–FG: the enterprise has formed an executive committee consisting of four decision-makers to choose the best candidate from another four participants to fill the vacancy. The committee has decided to consider eight qualitative attributes expressed in linguistic variables. The numerical example exhibited possibilities for improvement of human resources management as well as any other business decision area by applying MULTIMOORA–FG.