基于QFD电动汽车技术特性重要度的确定方法研究

技术重要度是开展电动汽车综合设计优化的目标函数,提出了一种基于QFD的电动汽车关键技术重要度的综合确定方法。方法分析了电动汽车顾客需求和电动汽车技术指标,基于质量屋建立顾客需求重要度与技术特性重要度耦合模型,应用粗糙数进行顾客需求重要度排序,根据电动汽车市场竞争性评估对其进行修正;应用灰色关联法确定顾客需求与技术特性之间的相关关系,分析电动汽车技术特性自相关关系建立相应的修正决策系统。基于该方法,以本研究院研究车型与市场同类车型进行实例分析,证明了方法的有效性和可行性。     

可伸缩产品平台优化设计的质量功能展开方法

为使基于产品平台的系列产品更好的满足顾客需求,提出一种基于质量功能展开的方法,可以优化设计可伸缩产品平台.该方法的主要思路是应用质量功能展开技术,建立单个产品的质量屋,确定其最优工程特性值,对每个工程特性进行敏感性分析,并根据所得的工程特性敏感性指标建立优化模型,求得最优的平台工程特性值和非平台工程特性值.优化模型的目标是最大化一个产品族中所有产品变体的顾客满意度的均值,约束主要包括顾客需求和工程特性之间的函数关系以及工程特性之间的自相关函数关系.模型中采用了线性函数形式,并采用回归方法来估计函数中的参数.给出一个工业卡钳的例子来验证所提方法的可行性,案例分析的结果表明,该方法比传统的两阶段方法能获得更好的顾客满意度.     

基于QFD的摩托车设计需求转换应用

质量功能配置(QFD)是一种把顾客需求转换为功能技术特性的有力工具。在转换过程中,顾客需求、顾客需求权重以及功能特性之间的关联性等大多是模糊数。针对摩托车产品设计的特点,以QFD方法的质量屋展开过程为纲领建立其工程模型,对顾客需求向产品的功能性能参数的转换进行分析研究,并在分析过程中应用一种基于量化的影响性分析方法,将定性分析和定量研究有机结合,为处理设计过程中的复杂性与不确定性问题提供了有效、科学的依据,具有实用价值。     

基于QFD与DOE模型的医疗消毒产品开发设计研究

为了在产品开发中提供更加可行有效的产品决策方案,提出质量功能展开(QFD)与正交试验设计(DOE)的集成模型。通过获取客户的质量需求及产品设计要点,运用正交试验设计方法进行技术特性的优化分析和参数设计,之后对P值进行显著性检验,分析工程特性对顾客需求的影响程度,最终确定顾客需求与工程特性之间的关联关系。将此模型应用于医疗消毒产品开发实例,验证了该模型具有可行性和有效性,也为同类医疗消毒产品开发设计提供了参考。     

基于群体模糊信息的产品规划中顾客需求的分析方法

为准确描述产品竞争性评价的模糊性,研究了产品规划质量屋中顾客需求综合优先度的确定问题。根据被调查顾客的顾客需求的群体基于三角模糊数的重要性评价,利用期望值算子处理规范化的顾客需求重要性的三角模糊评价以确定顾客需求的基本优先度。针对本企业及其竞争企业产品的基于三角模糊数的效用偏好及其顾客需求的基于三角模糊数的竞争评价,利用模糊总相似度最大化的原理建立顾客需求竞争优先度确定的优化模型,并通过拉格朗日函数的构造求解该模型。基于顾客需求的基本优先度及其竞争优先度的有机合成,确定了顾客需求的综合优先度。以某企业的产品设计实例进行应用研究,验证了该方法的合理性和可行性。     

在QFD中应用灰色关联度确定关联关系的研究

顾客需求与工程特性关联关系的确定是QFD的难点与重点.客观方法是利用质量屋中技术评估矩阵与竞争性评估矩阵确定关联关系.但获得大量数据是很困难的.针对这一问题,本文将灰色关联度引入QFD,以各项工程特性作为比较数列,各项顾客需求作为参考数列,看成灰色系统,利用灰色关联度分析确定顾客需求与工程特性的关联矩阵.实例表明,该法简便易行,能够利用少量数据确定QFD中关联关系.     

基于多种偏好信息的工程特性优先度确定方法

为有效评估质量功能配置中信息的模糊性,提出基于多种形式偏好信息的工程特性优先度确定方法.顾客需求与工程特性关联关系、工程特性自相关关系的评估信息容易获取且精确度较高,使用效用值进行判断;通过加权算术平均算子将判断信息与评估成员权重集结,进而将群体关联度矩阵、群体自相关矩阵和顾客需求最终重要度合成,得到各个工程特性的关联重要度;市场竞争性分析有较大的不确定性,引入多种形式的偏好信息表征各项工程特性的竞争潜力;利用转换函数将多种形式的信息一致化为模糊互补判断矩阵,进而使用行和归一化方法得到工程特性的竞争潜力因子;合成关联重要度和竞争潜力因子,确定工程特性的综合优先度.通过PE颚式破碎机新产品的开发实例,验证了所提方法的有效性和可行性.     

基于粗糙集理论的质量屋中工程特性确定方法

工程特性的确定过程中主要存在不准确、可行性差、合理性差等问题.为此,研究了基于粗糙集理论的质量屋中工程特性的确定问题.相应于质量屋中已确定的顾客需求,基于对初选集中工程特性的分析与整理,确定了工程特性的筛选集.针对顾客需求和筛选集中工程特性之间的广义关联关系不确定、不分明和模糊等特质,利用粗糙集中的有关方法确定了顾客需求与工程特性之间的广义关联关系.引入广义关联关系的强度阈值概念,以表征相应于每项顾客需求的广义关联关系的最低限度,进而通过集合运算确定了质量屋中的各项工程特性.最后,以洗衣机的产品研发为例,说明了所提方法的可行性.     

质量功能配置中工程特性最终重要度的确定方法

针对质量功能配置中顾客需求和工程特性之间的关联关系,以及各项工程特性之间的自相关关系均具有不确定、不分明和模糊等特性,分别提出关联关系和自相关关系确定的粗糙集方法,进而确定工程特性的初始重要度.对工程特性表现的改进比率的实现进行效率和风险分析,提出实现工程特性表现的改进比率的重要性概念及其计算公式.基于工程特性的初始重要度、实现工程特性表现的改进比率的重要性和"技术点"的合成,提出一种工程特性最终重要度的确定方法.以全自动洗衣机的产品研发为实例,说明所提方法的应用.     

产品规划中基于模糊效用偏好的顾客需求优先性分析

顾客需求市场竞争性分析是更为准确地确定顾客需求最终重要度的必要步骤,其有效性将直接影响产品规划质量屋的构建精确度。针对该分析过程中顾客对于竞争性产品偏好信息的模糊性,提出基于非对称三角模糊效用偏好的顾客需求竞争性评价矩阵的确定方法。利用三角模糊数中所定义的"距离"概念,构建以顾客需求竞争评价信息总相离度最大化为目标的单目标优化模型以确定顾客需求竞争性优先度。采用拉格朗日函数求解此优化模型,并对求解结果进行归一化处理以获取归一化的顾客需求竞争性优先度。通过与经典信息熵方法进行对比,论证了该方法的适用性及优势。     

A decision model for setting target levels in quality function deployment using nonlinear programming-based fuzzy regression and optimization

Quality function deployment (QFD) is a customer-oriented design tool for developing new or improved products and services to increase customer satisfaction. The inherent fuzziness of functional relationships between customer requirements and engineering characteristics, and among engineering characteristics in QFD modeling justifies the use of fuzzy regression. However, when linear programming is used in fuzzy regression, spread values of regression coefficients tend to approach zero. In order to overcome this problem, this paper employs a nonlinear-programming-based fuzzy regression approach to model functional relationships in product planning. Then, a fuzzy mathematical programming model is developed to determine target levels of engineering characteristics using the functional relationships obtained from fuzzy regression. Fuzzy mathematical programming model enables to account for the spread values as well as the center values of the parameter estimates of the functional relationships. A washing machine quality improvement problem is presented to illustrate the application of the proposed approach.     

A non-linear possibilistic regression approach to model functional relationships in product planning

Product planning is one of four important processes in new product development (NPD) using quality function deployment (QFD). In order to model the process of product planning, the first problem to be solved is how to incorporate both qualitative and quantitative information regarding relationships between customer requirements and engineering characteristics, as well as among engineering characteristics, into the problem formulation. The inherent fuzziness of functional relationships in product planning makes the use of possibilistic regression justifiable. However, when linear programming in possibilistic regression analysis is used, some coefficients tend to become crisp because of the characteristic of linear programming. To tackle the problem, a non-linear programming based possibilistic regression approach is proposed, by which more diverse spread coefficients can be obtained than from a linear programming approach. An emulsification dynamite packing-machine design is used to illustrate the performance of the proposed approach.     

质量功能展开中关联关系确定的粗糙集方法

针对质量功能展开中存在顾客需求和工程特性之间的关联关系不确定、不分明和模糊等特质,提出了质量功能展开中关联关系的粗糙集方法.由质量屋中所有工程特性组成条件属性集,且每一项顾客需求均组成相应的决策属性集,而后分别构造了对应于每项需求的决策系统.利用粗糙集中相对约简和相对核等方法,分别建立了相应的修正决策系统.利用信息熵和等价类的集成方法,获取了修正决策系统中各条件属性的重要度,进而确定了顾客需求和工程特性之间的关联关系.以全自动洗衣机的产品研发为实例,验证了方法的有效性.     

Applying CBR to machine tool product configuration design oriented to customer requirements

Product customization is a trend in the current market-oriented manufacturing environment. However, deduction from customer requirements to design results and evaluation of design alternatives are still heavily reliant on the designer’s experience and knowledge. To solve the problem of fuzziness and uncertainty of customer requirements in product configuration, an analysis method based on the grey rough model is presented. The customer requirements can be converted into technical characteristics effectively. In addition, an optimization decision model for product planning is established to help the enterprises select the key technical characteristics under the constraints of cost and time to serve the customer to maximal satisfaction. A new case retrieval approach that combines the self-organizing map and fuzzy similarity priority ratio method is proposed in case-based design. The self-organizing map can reduce the retrieval range and increase the retrieval efficiency, and the fuzzy similarity priority ratio method can evaluate the similarity of cases comprehensively. To ensure that the final case has the best overall performance, an evaluation method of similar cases based on grey correlation analysis is proposed to evaluate similar cases to select the most suitable case. Furthermore, a computer-aided system is developed using MATLAB GUI to assist the product configuration design. The actual example and result on an ETC series machine tool product show that the proposed method is effective, rapid and accurate in the process of product configuration. The proposed methodology provides a detailed instruction for the product configuration design oriented to customer requirements.     

基于模糊信息公理的产品功能需求优化方案选择

采用质量功能展开将顾客需求及重要度转化为产品功能需求及其重要度, 以信息公理为依据,选择信息量最小的功能需求配置方案。采用三角模糊数处理不确定性的质量功能展开信息,采用相对偏好关系分析进行质量功能展开计算,运用模糊信息公理计算定性功能需求的信息量。考虑功能需求间的非线性补偿关系,以总信息量最小化为目标建立0-1非线性规划模型。最后以某装载机功能需求方案规划为例,验证了所提出方法的有效性。     

质量功能展开中顾客需求的排序算法

研究了基于粗糙集的质量功能展开中顾客需求的排序问题.针对质量功能展开的顾客调查中需求不确定、不完备、不分明和模糊等非结构性特质,利用粗糙集中不完备信息系统的有关方法,提出了产品规划质量屋中顾客需求的确定方法.利用粗糙集中完备信息系统的多属性决策方法,确定了产品规划质量屋中上述顾客需求的基本重要度.基于卡诺模型的分析,提出了实现顾客需求竞争位次改进增量的重要性计算公式,进而确定了基本重要度的修正因子.基于顾客需求的基本重要度与其修正因子的合成,确定了顾客需求的最终重要度.最后,通过实例说明了所提方法的应用.     

A rough set enhanced fuzzy approach to quality function deployment

Quality function deployment (QFD) provides a systematic methodology to assist companies in developing quality products that are able to satisfy customer needs. The house of quality (HOQ), as the first phase of QFD, plays the most important role in product development. Frequently, fuzzy numbers are used to quantify the vagueness of linguistic terms so as to facilitate subjective assessments in the HOQ. However, the issue concerning how to determine the boundary intervals of fuzzy numbers remains unresolved. This work proposes a novel approach based on rough set theory, and introduces two concepts called rough number and rough boundary interval to address this issue. A comparative case study presented in this work shows that the proposed approach has significant advantages compared to the prevailing fuzzy number based method in processing subjective linguistic assessments in QFD.     

An intelligent estimation method for product design time

The planning and control of product development is based on the pre-estimation of product design time (PDT). In order to optimize the product development process (PDP), it is necessary for managers and designers to evaluate design time/effort at the early stage of product development. However, in systemic analytical methods for PDT this is somewhat lacking. This paper explores an intelligent method to evaluate the PDT regarding this problem. At the early development stage, designers lack sufficient product information and have difficulty in determining PDT via subjective evaluation. Thus, a fuzzy measurable house of quality (FM-HOQ) model is proposed to provide measurable engineering information. Quality function deployment (QFD) is combined with a mapping pattern of “function→principle→structure” to extract product characteristics from customer demands. Then, a fuzzy neural network (FNN) model is built to fuse data and realize the estimation of PDT, which makes use of fuzzy comprehensive evaluation to simplify structure. In a word, the whole estimation method consists of four steps: time factors identification, product characteristics extraction by QFD and function mapping pattern, FNN learning, and PDT estimation. Finally, to illustrate the procedure of the estimation method, the case of injection mold design is studied. The results of experiments show that the intelligent estimation method is feasible and effective. This paper is developed to provide designers with PDT information to help them in optimizing PDP.     

基于质量屋的设计方案选择模型

分析了质量功能展开中传统的设计方案选择所存在的问题，提出了一种新的设计方案评价方法。该方法以设计方案表现特性为评价指标，其取值可由模糊综合评判确定，进而以质量功能展开前两个阶段的产品规划质量屋和部件配置质量屋为展开工具，通过定义部件的表现特性函数，表现度等概念，建立了一个设计方案选择规划模型，仿真研究表明，该模型可以帮助设计人员系统考虑质量屋中自相关矩阵，企业资源及竞争企业对设计方案选择的影响，科学合理地配置产品部件设计方案，比传统方法更加科学、有效。