产品设计时间智能预测方法的研究

首先利用质量功能配置技术从设计要求中提取产品特征，从而确定影响设计任务所需时间的因素集；其次给出一种模糊神经网络模型来融合数据并实现时间的预测，该模型通过模糊综合评判来精简结构；最后通过注塑模具设计应用表明了该智能预测方法的有效性和可行性．     

一种基于模糊决策树的运动预测机制

通过考虑环境约束及用户运动的随机性,设计了一种基于模糊决策树的运动预测机制.该机制在示例集的基础上,利用属性模糊化和模糊分类熵建立初始模糊决策树,由此生成模糊决策规则进行预测,根据变化情况适时对模糊决策树进行必要的维护.仿真研究表明,该机制预测准确率较高,预测开销较小,是可行和有效的.     

分布式系统模糊航迹关联算法分析

目标航迹关联是分布式多传感器系统数据融合研究中的一个关键问题,传统航迹关联多采用统计相关的方法,计算较为复杂,且存在较大的不确定性.文中以分布式系统的航迹关联问题为研究对象,采用多因素模糊综合决策方法,建立了该算法的模糊因素集、评价集、单因素模糊矩阵、多因素模糊综合决策准则以及航迹关联质量域脱离质量等数学模型,最后给出了典型环境下的仿真结果,并与最近邻域法和K近邻法进行了比较,显示了该算法的优越性.     

广义犹豫模糊软集的相似度量及其应用

在广义模糊软集和犹豫模糊软集的基础上给出广义犹豫模糊软集的概念,并研究广义犹豫模糊软集的相似度量。首先利用三种犹豫模糊集合的包含度,构造犹豫模糊集间的相似度量公式。然后在犹豫模糊集相似度基础上给出广义犹豫模糊软集相似度量的公理化定义,并构造广义犹豫模糊软集的相似度量公式,这些公式可以计算参数集不同时两个广义犹豫模糊软集间的相似度。最后利用广义犹豫模糊软集相似度量方法构造了一种决策方法,并将这个决策方法应用于环境治理问题中。通过实例验证了所提出方法的可行性和有效性。     

关于Vague集的模糊熵

由于Vague集是Zadeh's模糊集的一个扩展,为计算Vague集的模糊熵,有学者提出将Vague集转化为模糊集,然后借用模糊集有关熵的计算方法来讨论它们。该文首先给出反例说明Li's(2003)的方法在某些情况下和基于模糊集的Vague集模糊熵定义不一致。在指出Vague集的模糊性主要来自未知信息和不确定性信息的基础上,提出了一个基于非模糊集的Vague集模糊熵公理化定义,给出了该类模糊熵的计算公式,最后通过定理证明了它确实同时考虑到了影响Vague集模糊熵的两个因素。     

基于ProA的产品开发过程建模

为了有效对制造企业产品开发过程管理,在应用IDEF0模型、分层Petri网和面向对象设计方法并在分析活动和过程关系的基础上,提出了基于活动及其实现过程(ProA)建模单元的过程模型的建立方法.详细对ProA数学建模,定义了ProA、ProA的输入/输出展开、ProA建模单元的典型运作、产品开发过程建模步骤.通过基于ProA的机电产品开发过程建模实例研究说明了其实用性.     

Vague集模糊熵的注记

Vague集模糊熵应该既有Vague集的未知性又有Fuzzy集的不确定性,在指出了现有Vague集模糊熵定义的错误,给出了一个真正考虑了两种因素的改进的Vague集模糊熵公理化定义,然后提出一种Vague集模糊熵的新计算模型,最后通过定理证明和已有方法分析,给出Vague集模糊熵的定义和计算模型是更加合理的。     

基于模糊神经网络的民航物流预测研究与仿真分析

为合理规划我国机场改扩建方案,针对目前民航业特点,从客运量的角度对民航物流预测进行研究,在综合分析影响客运量因素的基础上,提出了模糊对角回归神经网络滚动预测模型.此模型在前端网络处理层对不确定性因素进行模糊量化处理,对确定性因素进行归一化处理,有效地解决了模型输入量纲不一致的问题.通过实际数据的检验与内回归神经网络、外回归神经网络的预测结果相比较,证明应用此模型进行民航客运量预测有较高的预测精度.并在此基础上利用Visual Basic语言开发了民航物流预测仿真系统,对预测结果进行仿真验证,试验结果表明该仿真系统具有广阔的应用前景和推广价值.     

AHP与FUZZY在软件开发项目风险管理中的综合应用

归纳了软件开发项目的几大常见风险,在此基础上,通过集成层次分析法AHP和模糊综合评判法FUZZY的原理和模型,设计出软件开发项目风险评价的指标体系,并运用Delphi方法,让多名专家对各项指标赋权而得出每个指标的权重,之后通过风险因素U到模糊评判评语集V的模糊映射,得到模糊评估矩阵。最后根据FUZZY理论,运用模糊矩阵的合成运算,对软件开发项目风险进行两级评估,从而构建了集成方法下软件开发项目风险评价的过程和模型。结论对软件开发项目管理者具有实际参考价值。     

基于适应值模糊灰模型的交互式进化计算

针对交互式进化计算过程的评价不确定性问题,对个体适应值预测方法进行了研究。对于个体精确数适应值类型,提出基于模糊灰模型FGM(1,1)预测模糊适应值的方法,降低噪声对适应值的影响。首先,确定了用户满意度与适应值噪声强度的函数关系,构建了噪声强度衡量指标;然后,建立模糊适应值支集宽度约束下的最小噪声强度线性规划,求取模糊适应值预测参数;最后,通过模糊灰模型时间响应序列输出模糊适应值。采用NSGA-II范式实现进化计算,并设计了新的个体序值比较方法和拥挤测度计算公式。将所提方法应用于烤漆门外观选型问题, 并与已有典型方法比较。结果表明, 所提方法在推荐个体质量、减轻用户疲劳、提高搜索效率等方面均有优越性。     

基于协方差配置的采样估计

在工程应用中,状态估计的指标要求常常表现为误差协方差的形式.在充分考虑系 统内采样特性的基础上,提出了采样估计协方差的定义和一种新的采样估计方法,目的在于 设计离散估计器使采样估计协方差达到指定值,从而获得满意的稳定状态估计性能.将此采 样估计问题等价地转化为一个虚拟离散系统的估计器设计问题,给出了期望估计器的存在条 件及显式表示.数值例子说明了方法的有效性.     

Identifying requirements for communication support: A maturity grid-inspired approach

Communication is a critical success factor in design. It can be seen as the social and cognitive process by which information is selected, messages are exchanged between interacting partners, and meaning is created. How communication processes can best be captured, analysed and assessed, as a preliminary step toward suggestions for improvement of communication practices, remains a challenge for researchers and practitioners. To this end, a maturity grid-inspired approach to audit communication practices has been developed. This paper employs a maturity grid approach and reflects critically on the construction and application of the approach in a structured group workshop in software design. Such an approach yields dual benefits: (a) as a research method to gather insight into communication and (b) as a guide to plan improvements in practice. Conclusions are drawn for the process of auditing communication in design.     

Towards assessing the networkability of health care providers: a maturity model approach

This paper presents a networkability maturity model as an approach to assess a health care organisation’s capacity with regards to being able to efficiently engage in business relationships. Continuously rising costs and increasingly restrained budgets for health care put pressure on the public health systems. A low division of labour and integration of processes along cross-organisational patient therapy provides large potential for improvements in efficiency and efficacy. It is the aim of the presented model to enable identification of potentials for improvements and respective measures to advance the ability to benefit from specialisation and collaboration along the value chain. The presented model is developed based on a classification of related state-of-the-art in maturity models to assess individual factors of networkability which are integrated to form an overall framework comprising six components and respective factors to be assessed. As networkability maturity addresses the interrelation of strategy, organisational design and information systems design, the paper adheres to requirements for effective design science research applied to the process of construction of a networkability maturity model applicable for health care providers. It therefore concludes with a case-based evaluation according to the design research literature and identification of further research.     

Estimation of aircraft component production cost using knowledge based engineering techniques

A comprehensive method is presented to estimate aircraft component production costs using Knowledge Based Engineering (KBE) techniques. A suite of parametrical cost estimation blocks are treated as Cost Primitives (CPs), which contain attributes such as cost types, cost driving parameters, and cost estimation relationships. A CP is associated with a parameterized geometry and a set of specific design parameters including part/assembly types, materials and production methods. Production cost is estimated by aggregating the cost of different CPs within a tree structure integrating both product breakdown and cost breakdown structures. The cost analysis tool is integrated into a KBE application by building Capability Modules (CMs), which provide manufacturable geometric representations for cost estimation and can be used to summarize output reports for further optimization. Case studies concerning stiffened panels are carried out, verifying the accuracy of the cost estimation method and illustrating the applicability of this method together with the integrated KBE application for various aircraft components. The main contribution of this research is automating the cost integration in the design process to improve the fidelity, repeatability and traceability of cost analysis.     

Establishing a maturity model for design automation in sales-delivery processes of ETO products

Short delivery times are considered a competitive advantage in the engineer-to-order (ETO) sector. Design-related tasks contribute to a substantial amount of delivery times and costs since ETO products have to be either fully developed or adapted to customer specifications within tendering or order fulfillment. Approaches aiming at a computerised automation of tasks related to the design process, often termed design automation or knowledge-based engineering, are generally regarded as an effective means to achieve lead time and cost reductions while maintaining, or even improving product quality. In this study we propose a maturity model as a framework for analyzing and improving such activities in ETO companies. We contribute to the literature in being the first to investigate design automation in the ETO sector from a maturity perspective. Beyond that, we extend the extant literature on design automation, which is of a highly technical nature, by providing a framework considering organizational and managerial aspects. The findings indicate that five different levels of maturity can be achieved across the dimensions strategies, processes, systems, and people. Empirical cases give insight into these different levels. Our investigation draws from extant literature and a comparative case study involving four companies over two years.     

Robust, reduced-order, nonstrictly proper state estimation via the optimal projection equations with Petersen—Hollot bounds

A state-estimation design problem involving parametric plant uncertainties is considered. An error bound suggested by recent work of Petersen and Hollot is utilized for guaranteeing robust estimation. Necessary conditions which generalize the optimal projection equations for reduced-order state estimation are used to characterize the estimator which minimizes the error bound. The design equations thus effectively serve as sufficient conditions for synthesizing robust estimators. An additional feature is the presence of a static estimation gain in conjunction with the dynamic (Kalman) estimator, i. e., a nonstrictly proper estimator.     

异质性地表土壤冻融循环监测网络的优化采样设计-以黑河祁连山山前地区为例

在黑河祁连山山前地区建立分布式的土壤温度/水分传感器监测网络,准确获取异质性地表的遥感像元真值,用于地表冻融状态分类及土壤水分定量反演算法的发展完善和真实性检验,以及两者的降尺度研究均具有重要意义。传感器监测网络节点的空间布局直接影响观测有效性及其数据质量,一种基于异质性地表的均值估计方法被用于空间节点的优化采样设计：即以地表温度为目标变量,将研究区划分为相对均质的若干层(子区域),计算各层及总体的变异函数参数作为代价函数的输入,通过最小化目标变量的估计方差,实现传感器网络节点在各层的空间分布,准确地捕捉区域内部的异质性。结果表明,分层后各层的异质性相对于总体都有所下降,优化的节点空间布局具有较好的属性代表性,对于异质性较强的局部区域,有较高的样本密度。     

Globally stabilizing adaptive control design for nonlinearly-parameterized systems

In this note, a new adaptive control design is proposed for nonlinear systems that are possibly nonaffine and contain nonlinearly parameterized unknowns. The proposed control is not based on certainty equivalence principle which forms the foundation of existing and standard adaptive control designs. Instead, a biasing vector function is introduced into parameter estimate; it links the system dynamics to estimation error dynamics, and its choice leads to a new Lyapunov-based design so that affine or nonaffine systems with nonlinearly parameterized unknowns can be controlled by adaptive estimation. Explicit conditions are found for achieving global asymptotic stability of the state, and the convergence condition for parameter estimation is also found. The conditions are illustrated by several examples and classes of systems. Besides global stability and estimation convergence, the proposed adaptive control has the unique feature that it does not contains any robust control part which typically overpowers unknown dynamics, may be conservative, and also interferes with parameter estimation.     

Fault estimation observer design for discrete‐time systems in finite‐frequency domain

This paper proposes a framework of fault estimation observer design in finite‐frequency domain for discrete‐time systems. First, under the multiconstrained idea, a full‐order fault estimation observer in finite‐frequency domain is designed to achieve fault estimation by using the generalized Kalman–Yakubovich–Popov lemma to reduce conservatism generated by the entire frequency domain. Then, a reduced‐order fault estimation observer is constructed, which results in a new fault estimator to realize fault estimation using current output information. Furthermore, by introducing slack variables, improved results on full‐order fault estimation observer and reduced‐order fault estimation observer design with finite‐frequency specifications are obtained such that different Lyapunov matrices can be separately designed for each constraint. Simulation results are presented to illustrate the advantages of the theoretic results obtained. Copyright © 2014 John Wiley & Sons, Ltd.     

Dissipative interval observer design for discrete‐time nonlinear systems

This paper studies the problem of designing interval observers for a family of discrete‐time nonlinear systems subject to parametric uncertainties and external disturbances. The design approach states that the interval observers are constituted by a couple of preserving order observers, one providing an upper estimation of the state while the other provides a lower one. The design aim is to apply the cooperative and dissipative properties to the discrete‐time estimation error dynamics in order to guarantee that the upper and lower estimations are always above and below the true state trajectory for all times, while both estimations asymptotically converge towards a neighborhood of the true state values. The approach represents an extension to the original method proposed by the authors, which focuses on the continuous‐time nonlinear systems. In some situations, the design conditions can be formulated as bilinear matrix inequalities (BMIs) and/or linear matrix inequalities (LMIs). Two simulation examples are provided to show the effectiveness of the design approach.