混合不确定条件下基于信息公理的产品服务系统方案评价

针对基于信息公理的产品服务系统方案评价中,有一类评价指标的系统范围是随机变量,设计范围是模糊变量,其信息量计算涉及上下界为模糊数的积分,传统的信息公理无法直接计算的情况,提出系统和设计范围分别为随机和模糊变量的混合不确定条件下的信息公理方案评价方法,建立了模糊性和随机性共存的混合不确定指标模型,基于模糊模拟方法提出上下界为模糊数的信息量积分算法。以起重机产品服务系统方案评价为例,通过与传统的信息公理评价方法比较可知,所提方法能更有效地表达服务评价过程中决策者的意图,提高信息公理评价方法的准确性和实用性。     

基于混合不确定信息公理的产品服务系统概念方案评价

针对区间变量、不确定语言变量和混合不确定变量共存的产品服务系统概念方案评价问题,拓展了混合不确定信息公理方法。首先,采用线性变换法分别对上述三类数据进行规范化处理,采用熵权法确定指标权重;其次,分别用传统信息公理和模糊信息公理计算区间变量和不确定语言变量的信息量,针对模糊性和随机性共存的混合不确定指标,其信息量的计算涉及到上下界为模糊数的积分,通过重心法和符号法将模糊设计范围反模糊化,得到系统范围的积分上下限;最后,将各指标的信息量加权求和得到各方案的信息量,按信息量的大小确定出最优方案。最后,以某公司汽车产品服务系统方案评价为例,证明了所提方法的可行性和有效性。     

基于模糊信息公理的设计方案评价方法及应用

针对产品设计过程中方案评价的特点,提出了一种基于模糊信息公理的设计方案评价方法.该方法利用信息公理与模糊数学原理将模糊信息数值化,决策者不必给出各评价指标的权重,只需确定各指标的设计范围和系统范围,通过计算各指标的信息量,求出每个方案的总信息量,即可比较各方案的信息量大小,确定最佳设计方案;同时,根据用户需求,可以修改各评价指标的设计范围,得到满足不同偏好的满意方案,使整个评价过程更加灵活.为满足模糊评判的需要,说明了模糊系统范围的含义并对模糊信息量的计算公式加以适当的修正.将该方法应用于变幅机构吊重水平位移补偿系统的设计评价中,验证了其有效性.     

模糊信息公理及在设计方案评价中的应用研究

在信息公理的基础上,引入了模糊信息公理的概念。提出了基于模糊信息公理的评价方法。决策者在决策时无需给出各设计指标的具体权重,只需设定各指标的设计范围和系统范围,计算各指标的信息量,通过比较各设计方案的信息量选出最优方案。从而将整个决策过程置于一个更加灵活自然的框架中,更充分地表达了决策者的主观偏好,更符合工程实际情况。应用实例表明了基于模糊信息公理的评价方法的有效性和实用性。     

基于模糊信息公理的可配置产品设计方案评价方法及应用研究

针对可配置产品的设计方案评价问题,提出了一种考虑耦合度的模糊信息公理评价方法。该方法通过模糊数学理论将难以计算的定性评价指标信息量化,将定量指标和定性指标统一量化计算,解决了信息公理中定性指标信息量难以计算的难题,各指标的权重由层次分析法来确定。在计算信息量的同时,考虑了耦合度对方案评价的影响,并将其量化,与各权重一起在信息量计算公式中体现出来。通过比较各方案的总信息量,选择总信息量最小的方案为最优方案。最后,以某单兵系统方案设计评价为例验证了该方法的可行性和有效性。     

基于信息公理的混合型多属性产品方案评价

研究了指标属性值包含实数、区间数和模糊数的混合型多属性产品方案评价问题,考虑了评价指标设计范围不确定的情况,提出了一种基于信息公理的评价模型,并给出了具体的评价方法和步骤.通过确定每个方案各指标满足功能要求的概率,计算各方案的信息量,以信息量为统一测度比较方案间的优劣程度,实现方案的优劣排序.决策者不必给出各评价指标的权重,也不需要对决策矩阵进行规范化,从而为解决混合型多属性评价优选问题提供了一条新的途径.以汽车起重机综合评价为例,说明了信息公理的混合型多属性评价方法的可行性.     

基于直觉模糊余弦相似度的云制造服务质量评价

云制造环境下云资源种类丰富且服务制约因素多,导致云制造服务质量评价困难.针对专家决策与用户评价信息的不确定性,以及评价指标类型多样的问题,提出基于直觉模糊余弦相似度的服务质量评价方法.采用可表达隶属度信息与非隶属度信息的直觉模糊数对非可量化的服务质量进行评价,并采用不受指标类型与维数限制的余弦相似度计算各个云制造服务属性值与理想值之间的相似度.对可量化与非可量化服务质量属性相似度进行加权平均得到综合相似度,依据其大小对云制造服务质量进行排序.最后,以某机床制造厂的涡轮生产为例验证了所提方法的有效性.     

粗糙信息公理与云模型集成的方案评价方法

传统的基于多准则决策的方案评价方法均基于专家的主观决策确定指标的优劣程度,并且方案排序结果难以直观地判断方案的优劣程度。针对该问题,将信息公理可量化指标设计程度的优势和云模型可进行定量信息转化的优势相结合,提出了信息公理与云模型集成的方案评价方法。相比于模糊集方法,粗糙集不需要先验信息,能够客观地处理模糊以及不确定的评价指标信息,提出了基于粗糙信息公理的方案指标评价方法。以方案评价指标信息量为云滴,运用逆向云模型将信息量转换为定性的方案评价,进而通过云数字特征对方案进行分析。以某装载机设计方案为例,验证了所提方法的有效性。     

机械产品方案设计模糊综合评价中隶属度转换的新方法

因为机械产品方案设计评价包含诸多模糊性,所以模糊综合评价成为机械产品方案设计评价的优势模型。在模糊评价矩阵确定后,模糊评价的核心计算是隶属度转换,但是,现有的隶属度转换算法不正确,因为各指标隶属度中原本对方案分类不起作用的冗余值,也被用于计算方案隶属度。要使构建的隶属度转换方法不受冗余数据干扰,关键是弄清楚各指标隶属度究竟提供给方案怎样的分类信息。为此,用基于熵的数据挖掘方法,通过挖掘隐含在指标隶属度中关于方案分类的知识信息,理清方案分类与各指标隶属度间的关系,通过定义区分权清除指标隶属度中对方案分类不起作用的冗余值,最终确定出各指标隶属度提供给方案的分类信息,正确实现隶属度转换。由此建立机械产品方案设计模糊综合评价中隶属度转换的新算法。     

基于改进DEMATEL-VIKOR混合模型的产品概念方案评价

针对当前产品方案评价方法存在的不足,提出一种基于直觉模糊理论的多属性决策模型。该模型结合决策试验与评价试验方法和MCDM算法,引入直觉模糊理论表达信息的不确定性。在传统决策试验与评价试验方法的基础上引入拆分矩阵法以维持综合影响矩阵的直觉模糊特性,由改进决策试验与评价试验方法对产品方案评价系统中的评价指标进行量化分析,其结果以可视化的形式呈现,表达了各评价指标的量化因果关系,同时根据量化结果对指标集进行因果分类、重要度排序和权重分配;在VIKOR算法中改进理想解和负理想解的定义,以折中规划法为核心,提供最大化群体效益与最小化个别遗憾相妥协的备选方案最佳排序,得到距离理想解最近的折中可行方案。以螺杆式注塑机的方案评价为例,证明了该方法在工程应用中的可行性和有效性。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.