AAK Theorem and a Design of Multidimensional BIBO Stable Filters

Rational approximation theory occupies a significant place in signal processing and systems theory. This research paper proposes an optimal design of BIBO stable multidimensional Infinite Impulse Response filters with a realizable (rational) transfer function thanks to the Adamjan, Arov and Krein (AAK) theorem. It is well known that the one dimensional AAK results give the best approximation of a polynomial as a rational function in the Hankel semi norm. We suppose that the Hankel matrix associated to the transfer function has a finite rank.

Method for Functional Design of Axiomatic Design Based on Connections

Axiomatic design(AD) is a popular design method,and satisfying the independence axiom is the basis of AD.However,AD doesn't provide methods to decompose functions then keep them independent and to handle coupled design.A few of ways of handling coupled design are mainly passive resolutions when coupled design exists,but not efficient to each product design.Hence,this paper presents an innovative approach to design and decompose functions of complex products based on functional connections,aiming at actively avoiding functional coupling.By contrasting with component networks,four kinds of relations among functions are identified,including spatial,energy,material,and information connection.Then the definitions of these relations and the dominant connection are given.Based on the definitions,the principles of functional decomposition and design are developed,in which each non-leaf function is broken into sub functions centered on its dominant connection with avoidance of functional cross and coupling,and sequentially satisfies the independence axiom.Then the operational flow of the proposed approach is constructed.Determining the dominant connection of a function,decomposing the function into sub functions in terms of the dominant connection and reverse examination and optimization are planed as the core steps in each zigzagging.Input process output(IPO) analysis is introduced to obtain the dominant connection of a function,some rules for examining and optimizing the decomposition results reversely according to oriented object theory are presented as well.An illustrative example about the pouring function of squeeze casting equipments presented demonstrates how to use the proposed approach,and indicates its effectiveness.The proposed approach expands the principles of AD,constructs a guidance policy for independent functional design of complex products based on AD,and can help decrease or actively avoid coupled design and improve design efficiency.

Functional design of wind turbine airfoils based on roughness sensitivity characteristics

To improve aerodynamic performance of wind turbine airfoils,the shape profile characteristic of the airfoil is investigated.Application of conformal transformation,one functional and integrated expression of wind turbine airfoils is presented.Using the boundary layer theory,the aerodynamic model with roughness of wind turbine airfoils is introduced by studying flow separation around the airfoil.Based on the shape expression and aerodynamic performance of airfoils,the function design of wind turbine airfoils is carried out that the maximum lift-drag ratio and low roughness sensitivity are designed objects.Three wind turbines airfoils with different thickness are gained which are used at tip part of blades.As an example,the aerodynamic performance of one designed airfoil with relative thickness of 15%is simulated in different conditions of clean surface,rough surface,laminar flow and turbulent flow.The comparison of aerodynamic performance between the designed airfoil and one popular NACA airfoil is completed which can verify the better performance of the designed airfoil and reliability of the designed method.

QUALITY FUNCTION DEPLOYMENT IN BOTTOM-UP PROCESS FOR DESIGN REUSE

To deal with a bottom up process model for design reuses a specific extended house of quality(EHOQ)is proposed Two kinds of supported functions,basic supported functions and new supported functions,are defined.Two processes to determine two kinds of functions are presented A kind of EHOQ matrix for a company is given and its management steps are studied.

Reliable Space Pursuing for Reliability-based Design Optimization with Black-box Performance Functions

Reliability-based design optimization(RBDO) is intrinsically a double-loop procedure since it involves an overall optimization and an iterative reliability assessment at each search point.Due to the double-loop procedure, the computational expense of RBDO is normally very high.Current RBDO research focuses on problems with explicitly expressed performance functions and readily available gradients.This paper addresses a more challenging type of RBDO problem in which the performance functions are computation intensive.These computation intensive functions are often considered as a"black-box"and their gradients are not available or not reliable.On the basis of the reliable design space(RDS) concept proposed earlier by the authors, this paper proposes a Reliable Space Pursuing(RSP) approach, in which RDS is first identified and then gradually refined while optimization is performed.It fundamentally avoids the nested optimization and probabilistic assessment loop.Three well known RBDO problems from the literature are used for testing and demonstrating the effectiveness of the proposed RSP method.

Analysis of solution findings in the conceptual design of function structures

In the conceptual stage the function design process is realized by the computer aided application. After surveying on the function specification methods and the function modeling, a computer aided function design environment is analyzed. Subsequently based on a module library and principle catalogue, a solution finding process as a part of conceptual design is proposed for a creative design. In addition, a search algorithm to find the solution of adaptable function structure is also discussed. The concepts proposed in this paper can support the subsequent design stages, especially simulation for checking the function structure defects.

Optimum Weight Design of Functionally Graded Material Gears

Traditional gear weight optimization methods consider gear tooth number, module, face width or other dimension parameters of gear as design variables. However, due to the complicated form and geometric features peculiar to the gear, there will be large amounts of design parameters in gear design, and the influences of gear parameters changing on gear trains, transmission system and the whole equipment have to be taken into account, which increases the complexity of optimization problem. This paper puts forward to apply functionally graded materials(FGMs) to gears and then conduct the optimization. According to the force situation of gears, the material distribution form of FGM gears is determined. Then based on the performance parameters analysis of FGMs and the practical working demands for gears, a multi-objective optimization model is formed. Finally by using the goal driven optimization(GDO) method, the optimal material distribution is achieved, which makes gear weight and the maximum deformation be minimum and the maximum bending stress do not exceed the allowable stress. As an example, the applying of FGM to automotive transmission gear is conducted to illustrate the optimization design process and the result shows that under the condition of keeping the normal working performance of gear, the method achieves in greatly reducing the gear weight. This research proposes a FGM gears design method that is able to largely reduce the weight of gears by optimizing the microscopic material parameters instead of changing the macroscopic dimension parameters of gears, which reduces the complexity of gear weight optimization problem.

TOPOLOGY DESCRIPTION FUNCTION BASED METHOD FOR MATERIAL DESIGN

这篇论文的目的是在材料设计调查拓扑学描述功能(TDF ) 的应用程序。使用 TDF 与规定机械性质描述微观结构，明确的表达和材料的设计问题的解决的技术的拓扑学被介绍。由作为参数决定的一系列基础函数的和介绍 TDF，因为设计变量的一个尺寸优化问题是 TDF 基础函数和设计域的网孔的独立人士的参数，材料微观结构的拓扑学优化被提出。由这个方法，为在设计领域描述成分材料的分发的高质量的拓扑学能被获得，经常在可变密度方法遇见的棋盘问题被避免。与常规水平集合方法相比，没有这个过程，优化问题能被存在优化技术简单地解决解决“ Hamilton-Jacobi-type ”由差别方法的方程。建议的方法与二个 2D 例子被说明。一个人与积极泊松的比率给联合起来的房间，其它与否定泊松的比率。例子证明方法为材料设计基于 TDF 是有效的。

DESIGN AND PROPERTIES OF A FUNCTIONALLY GRADIENT CERAMIC TOOL MATERIAL

Based on the analyses of the severity of cutting process as well as the failure mechanisms of ceramic tools, a model for designing functionally gradient ceramic tool materials with symmetrical distribution is presented, by which a Al 2O 3/(W,Ti)C ceramic tool material FG 2 was developed. Multi objective optimization method was employed in designing the compositional distribution of this ceramic tool material. The results of both continuous and intermittent cutting tests are indicative of the much better cutting behavior of the functionally gradient ceramic tool FG 2 than that of the common ceramic tool SG 4.

Design of Co-sedimentation Experiments Used to Fabricate Functionally Graded Materials with a Continuous Change of Composition

In the process of particle settling in a dilute,a density graded distribution of the liquid below the suspension needs to be designed according to the gravity of the suspension prior to sedimentation.In the present paper a compositionally graded W-Mo composite was formed via the settling of the W and Mo particles,with a density gradient distributed in the initial clear liquid along the settling direction.

Function and Design Idea of UHVDC Test Base

The function of the UHVDC test base of the State Grid Corporation of China (SGCC) is oriented to serve UHVDC power transmission and substation projects, especially power transmission from West China to East China, and to promote localization of UHVDC transmission and substation equipment. In essentials, this test base consists of UHVDC test transmission line, corona cage, outdoor test site, UHV test hall, pollution and environment laboratory, electromagnetic environment simulation test site, insulator laboratory, arrester laboratory and live equipment test field. This paper introduces the function and design idea of the test base, presents the main performance parameters of the above-mentioned test facilities, and summarizes the matters of concern when siting and planning.

Application of the optimal Latin hypercube design and radial basis function network to collaborative optimization

Improving the efficiency of ship optimization is crucial for modern ship design. Compared with traditional methods, multidisciplinary design optimization (MDO) is a more promising approach. For this reason, Collaborative Optimization (CO) is discussed and analyzed in this paper. As one of the most frequently applied MDO methods, CO promotes autonomy of disciplines while providing a coordinating mechanism guaranteeing progress toward an optimum and maintaining interdisciplinary compatibility. However, there are some difficulties in applying the conventional CO method, such as difficulties in choosing an initial point and tremendous computational requirements. For the purpose of overcoming these problems, optimal Latin hypercube design and Radial basis function network were applied to CO. Optimal Latin hypercube design is a modified Latin Hypercube design. Radial basis function network approximates the optimization model, and is updated during the optimization process to improve accuracy. It is shown by examples that the computing efficiency and robustness of this CO method are higher than with the conventional CO method.

Product design on the basis of fuzzy quality function deployment

In the implementation of quality function deployment (QFD),the determination of the target values of engineering characteristics is a complex decision process with multiple variables and multiple objectives that should trade off,and optimize all kinds of conflicts and constraints.A fuzzy linear programming model (FLP) is proposed.On the basis of the inherent fuzziness of QFD system,triangular fuzzy numbers are used to represent all the relationships and correlations,and then,the functional relationships between the customer needs and engineer- ing characteristics and the functional correlations among the engineering characteristics are determined with the information in the house of quality (HoQ) fully used.The fuzzy linear programming (FLP) model aims to find the optimal target values of the engineering characteristics to maximize the customer satisfaction.Finally,the proposed method is illustrated by a numerical example.

Path Analysis of Agricultural Project Design Based on Function Expansion: A Case Study of Naya Mountain Villa

The expansion of agricultural function is one of the important means for modern agricultural projects to promote agricultural economic benefits. Successful modern agricultural projects require good creative ideas and design programs. While developing high-efficient modern agricultural production activities,we should fully explore the intangible value of agricultural production activities,combine agriculture with agricultural products,natural conditions,cultural conception and other effective resources,to expand agricultural functions,and promote comprehensive benefits. In order to build a sustainable modern agricultural project operation system,Naya Mountain Villa project planning is taken as an example for analysis. Naya Mountain Villa began construction in 2011; the creative planning based on the agricultural expansion function was carried out in 2013; it had successful access to the capital market in 2015. The project realizes the effective integration of agricultural production system and agricultural function expansion,constructs a set of long-term stable profiting models,and lays an important foundation for entering the capital market. The project is a representative example of the function-expanding modern agricultural project. Through the analysis of the design ideas of the project,this paper discusses the function expansion elements of basic resources,public welfare and agricultural function expansion methods,the formation of general ideas,source and construction logic of creative thinking,and summarizes and abstracts some inspiring design methods of agricultural function expansion. Through the analysis of the key points in the design of the specific technical aspects of the project,this paper provides a reference for solving common difficult problems in the practical design. The summary and refinement of the thinking logic,thinking construction and specific design method of the project is inspiring and repeatable to some extent,which can provide reference for the relevant researchers.

Optimization design and residual thermal stress analysis of PDC functionally graded materials

The distribution of thermal stresses in functionally graded polycrystalline diamond compact (PDC) and in single coating of PDC are analyzed respectively by thermo-mechanical finite element analysis (FEA). It is shown that they each have a remarkable stress concentration at the edge of the interfaces. The diamond coatings usually suffer premature failure because of spallation, distortion or defects such as cracks near the interface due to these excessive residual stresses. Results showed that the axial tensile stress in FGM coating is reduced from 840 MPa to 229 MPa compared with single coating, and that the shear stress is reduced from 671 MPa to 471 MPa. Therefore, the single coating is more prone to spallation and cracking than the FGM coating. The effects of the volume compositional distribution factor (n) and the number of the graded layers (L) on the thermal stresses in FGM coating are also discussed respectively. Modelling results showed that the optimum value of the compositional distribution factor is 1.2, and that the best number of the graded layers is 6.

Structural analysis and design of frost resistance function for subgrade of high-speed railway ballasted track in cold regions

According to the technical characteristics of short fixed wheelbase of a high-speed carriage, a subgrade-track integrated space mechanical response analysis model is proposed for trains under the action of biaxial load after the comparison of the stress distribution characteristics of the ballast track subgrade bed structures for high-speed railway under the action of uniaxial load and biaxial load. The loading threshold value(high-cycle long-term dynamic strength) under the circumstance where the cumulative deformation of subgrade structure gradually develops and finally reaches the convergent state, and its relationship with the foundation coefficient K30 were deduced, based on the characteristics of cumulative deformation evolution obtained from the unit structure filling model test under the action of cyclic loading. In view of structure stability and frost resistance requirements of the railway subgrade in cold regions, technical conditions to maintain good service performance of subgrade structure of high-speed railway ballasted track are discussed and analyzed. Study results show that the additive effect manifests itself obviously for railway train bogies under the action of biaxial load than uniaxial load, which has a significant dynamic effect on the subgrade bed bottom and a slight effect on the surface layer. Thus, the adoption of a biaxial load model in the design of a high-speed railway subgrade accurately reflects the vehicle load. Pursuant to the structure design principle, the design method of the subgrade structure of high-speed railway ballasted track is proposed to meet the technical requirements such as structural strength, bearing stiffness and high-cyclic and long-term stability. Technical indicators are obtained for the variation of thickness of the surface layer of reinforced subgrade bed in the double-layer subgrade mode along with the change of K30 at the subgrade bed bottom. The double-layer structure mode of "closure on the upper layer and drainage on the lower layer" was proposed in order to meet the waterproofing and drainage requirements of the upper layer of the subgrade bed in cold regions. A dense-framework graded gravel filler with weak water permeability at a coefficient of 10-4 cm/s is used on the upper layer and the void-framework graded gravel filler at the water permeability coefficient of 10-2 cm/s is adopted on the lower layer.

专利数据辅助的新产品概念设计方案生成方法

在生成新产品概念设计方案的过程中,企业常缺乏辅助新产品功能描述、分解及创新的设计知识,且存在功能实现技术检索结果可用性不高、难以有效转化为概念设计方案技术特征的问题。为此,提出一种专利数据辅助的新产品概念设计方案生成方法。首先,使用文本相似度算法,检索国际专利分类表中与设计任务相关的分类号文本,辅助描述新产品的主功能。其次,引入C-K理论将下级分类号释义视为K空间中的元素,新产品子功能视为C空间中的元素,通过元素间转化辅助完成主功能分解。再次,结合专利技术成熟度分析和功能创新策略,确定新产品的功能创新方向,并依据共现分类号释义预测新产品的集成功能,辅助实现新产品的功能创新。接着,应用专利文献跨域特征分析模型,引入技术领域融合度的概念,量化专利技术的知识广度和流动性,辅助优选功能实现技术,并利用语义解析技术自动提取专利独立权利要求中的技术特征,辅助生成新产品概念设计方案。最后,将该方法应用于重型汽车底盘预装设备领域的新产品开发,证明了方法的有效性。

冬季运动服装装备的功能性设计实践研究

目的为了深入探讨冬季运动服装装备的功能性设计实践研究的发展态势,对我国冬季运动服装装备的功能性设计实践及其发展趋势进行系统化的梳理和分析,明确我国冬季运动服装装备未来的发展趋势及其应用的可行性。方法首先对冬季运动服装装备进行概述,其次利用文献分析法总结冬季运动服装装备的发展历程和现状,最后对冬季运动服装装备的发展趋势进行预测。结果以冬季运动服装装备设计为例,提出了一种新的冬季运动服装装备设计思路,设计制作强调了功能性和用户体验的平衡。结论通过研究冬季运动服装装备的功能性设计实践及在中国冰雪大势的机遇下,提供了一种新的视角来看待冬季运动服装装备的设计,为未来的产品开发和创新提供有价值的参考。

面向物流需求场景的智慧公路功能设计

推动智慧公路建设是提升交通安全与服务水平、提高通行效率的重要手段之一。本文梳理了中国智慧公路功能设计方面的研究现状,分类汇总了中国智慧公路现有功能及相关应用案例。同时,基于高速公路和城市道路的行车、停车场景以及政府行业监管需求,总结了中国公路物流行业运营痛点和需求场景,提出了面向物流场景需求的智慧公路功能设计思路,为中国智慧公路建设提供了新的理论参考和设计思路。