基于产品功能参数的灰色成本估计

首次提出了灰色线性回归模型，并应用该模型建立了产品成本与功能参数之间的函数关系，然后根据产品的功能参数估计产品成本。通过实际计算，取得了满意结果，该模型可用于系列产品生产中新产品的成本估计。     

功能参数与设计成本的关联分析

成本是一项综合指标,受多种因素的影响。但在一定的外部环境和内部条件下,产品设计成本直接与其功能参数有关,表现为功能参数的函数。研究成本与参数的关联特性,建立它们的函数关系,有利于制定目标成本,导控产品开发与设计;有利于进行参数成本优化分析,提出经济合理的设计方案。按参数是单项还是多项,可分为单参数成本关联分析和多参数成本关联分析。1 单参数成本关联分析设主要产品功能参数为J,成本记为C,两者的关联函数可表达为: C=f(J) 不同的产品,关联特性不同。对于一定     

基于模糊支持向量机的产品设计时间估计方法

针对产品设计时间估计中存在的小样本、不确定性数据等问题，将模糊回归理论与支持向量机方法相结合，提出一种Fv-SVM模型，给出相应的设计时间智能估计方法和参数优选算法。进行了注塑模具设计的实例分析，结果表明基于Fv-SVM的时间估计方法是有效和可行的。     

基于参数成本估计法的航天器研制生产成本管控

针对新阶段航天器成本精细化管控的要求,根据航天器科研生产主要环节与分工协作关系,提出了基于参数成本估计法的航天器二维度三阶段研制生产成本管控模型,以供配电分系统为例进行了案例研究。在论证阶段,探索功能与成本的估算关系,基于参数成本估计法构建成本管控模型;在研制阶段,根据分系统历史成本数据,构建预分预控管控模型将总成本合理分解至各承研所厂;在成本管控阶段,基于蒙特卡洛仿真制订激励-约束政策,统筹航天器创新发展与成本管控要求。案例丰富了成本管理的实践研究,对促进我国宇航企业科研生产模式转型升级具有一定的借鉴意义。     

基于PSO的三参数威布尔分布参数的联合估计方法

针对图估计及双线性回归估计存在的弊端,将双线性回归估计和极大似然估计(MLE)结合起来,形成一种对三参数威布尔分布参数的联合估计.详细分析了联合优化的核心工具--粒子群优化(PSO)算法的特点、实现和收敛指标,并对基于双线性回归的初值获取作了分析.以仿真和实际例证为基础,详细评析了联合估计参数的优点和缺陷.结果表明:基于PSO优化的联合估计在一定程度上对三参数威布尔分布参数的搜索具有良好的性质,其具体体现为搜索准确和稳定.     

基于小波神经网络的设计阶段成本估计

机械产品的成本构成复杂，在其设计阶段进行成本估计十分必要。在使用神经网络进行成本估计的基础上，利用小波分析对网络进行了改进，提高了收敛速度，并给出例子，在Matlab中进行了计算。     

基于BP神经网络的覆盖件模具机加工成本估计

在分析常用的模具成本估计方法的基础上,提出了构造模具机械加工成本神经网络计算方法;同时,引入了测差样本方法,用区间估计来为模具机加工成本报价;以铸造整体结构拉延模具为例,利用企业的历史数据组成训练样本集,训练所形成的神经网络;并对前壁板上梁铸造整体结构拉延模具的机加工成本进行了估计.计算结果显示了该方法的可行性.     

模糊可靠度的区间估计方法

对模糊可靠度进行了分类，建立了三种常见类型模糊可靠度区间估计的计算模型，给出了模糊可靠度置信区间的确定方法。实例分析表明了模糊可靠度区间估计的实用价值。     

基于4D信息模型的机械产品装配成本动态估计方法研究

介绍了产品4D信息模型的构造和特点,并在此基础上研究了设计制造资源层次模型及其对应的结构化编码系统（SCS）。结合实际,研究了以结构化编码系统为基础进行产品装配成本动态估计的原理与方法。     

基于线性回归模型的机电产品再制造费用预测

针对再制造决策者在产品再制造成本发生前无法决策的问题,提出运用线性回归模型,建立产品零部件失效类型信息与产品再制造费用之间的线性关系;基于同类产品零部件失效类型信息以及同类产品再制造费用的统计,对产品的再制造费用进行事前预测,并根据各类零部件的质量属性,对产品再制造的预测费用进行修正,获得相对准确的产品再制造费用预测,并用预测费用与实际费用的相对误差描述再制造费用预测的准确性。     

基于模糊支持向量机预测胎重的方法研究与比较

胎重的准确预测在胎儿监护中具有重要作用,为提高胎重预测的准确性,提出一种基于模糊支持向量机的预测方法。通过在支持向量机中引入模糊逻辑,抑制由测量误差造成的异常数据对预测模型训练的影响,提高了胎重预测对参数测量误差的鲁棒性。对600例数据构成的训练集和150例数据构成的测试集进行应用,比较了模糊支持向量机和以前的回归方法、误差反向传递神经网络、支持向量机在胎重预测中的性能。结果表明:与其它方法相比,模糊支持向量机能获得更准确的胎重估计。     

集成化产品成本估计系统设计

成本估计是产品设计中非常重要的环节,分析了成本估计工作中存在的问题;指出了信息集成是成本估计的亟待解决的关键问题;设计了集成化成本估计的支持系统,该系统将CAD产品结构信息,CAPP中的工艺信息和MRPⅡ中的工作中心信息进行系统集成,通过系统实现提高了成本估计的精度;缩短了成本估计的时间;扩大了成本估计的范围。     

机电产品设计过程中的成本估算与控制方法研究

采用基于模糊理论的加权相似方法估算零部件的成本,同时利用占比计算系统得到零部件的目标成本,通过计算改进率确定修改优先级,以此达到控制产品成本的目的.以CNC机床的传动系统开发为例论述了方法的应用,结果表明,提供的方法可以很好地控制产品的寿命周期成本.     

The process modelling of epoxy dispensing for microchip encapsulation using fuzzy linear regression with fuzzy intervals

Epoxy dispensing is a popular way to perform microchip encapsulation for chip-on-board (COB) packages. However, the determination of the proper process parameters setting for a satisfactory encapsulation quality is difficult due to the complex behaviour of the encapsulant during the dispensing process and the inherent fuzziness of epoxy dispensing systems. Sometimes, the observed values from the process may be irregular. In conventional regression models, deviations between the observed values and the estimated values are supposed to have a probability distribution. However, when data is scattered, the obtained regression model has too wide of a possibility range. These deviations in processes such as epoxy dispensing can be regarded as system fuzziness that can be dealt with satisfactorily using a fuzzy regression method. In this paper, the fuzzy linear regression concept with fuzzy intervals and its application to the process modelling of epoxy dispensing for microchip encapsulation are described. Two fuzzy regression models, expressing the correlation between various process parameters and the two quality characteristics, respectively, were developed. Validation experiments were performed to demonstrate the effectiveness of the method for process modelling.     

Measurement of synchronous machine parameters using Kalman filter based fuzzy logic estimator

This paper presents a new Kalman filter/fuzzy logic approach for estimating synchronous machine parameters from short circuit tests. The technique uses on-line noisy measurements of the short circuit current for estimating direct axis reactances, and time constant synchronous machine parameters. The approach is based on expressing short circuit current as a discrete time linear dynamic system model suitable for the Kalman filter to estimate the parameters. Fuzzy rule-based logic is used to tune-up measurement noise levels by adjusting the covariance matrix. The results show a better convergence using fuzzy logic than those solely using the Kalman filter.     

Developing an integrated framework for feature-based early manufacturing cost estimation

The major objective of concurrent engineering is to consider the related downstream manufacturing during the design stage. Estimating manufacturing cost during the early design stage is one area that has been given little attention by researchers. However, if the product manufacturing cost can be estimated during the design stage, designers can modify a design to achieve proper performance as well as a reasonable cost at an early stage of the product development process.Basically, manufacturing cost is determined by shape complexity, product precision and tooling process. That is, if these data can be obtained and considered during the design stage, estimating manufacturing cost during the early product development stage will become a feasible task.In this research, a framework for estimating the manufacturing cost in terms of a feature-based approach is proposed. This system tends to estimate the manufacturing cost of a design according to the shapes and precision of its features. The objective of this research is to provide a tool to assist a designer, who has little knowledge about the manufacturing process, to estimate the fabrication cost of a design during its conceptual stage, in order to reduce unnecessary costs in the downstream process.     

An integrated system for process planning and cost estimation in hole making

The process planning function plays a critical role not only in computer integrated manufacture, but also in the economics of batch manufacturing. This paper describes the development of a generic knowledge-based system for process planning and cost estimation in the hole making process. The main function of the system, besides estimating the cost of production, is to recommend appropriate processes, their sequence and their respective machining conditions in order to obtain the required product specifications. The system has been implemented in a manufacturing organisation. The results obtained have indicated that in addition to cost savings the system also preserves the consistency in planning and cost estimation.