基于复合变换的人脸光照补偿方案

分析了非线性变换对图像产生的影响,提出一种复合变换补偿的方法.该方法产生的变换曲线两端起伏剧烈而中间平缓,有效地扩充了中间正常光照区域.选取了过亮、过暗和偏光等不同光照条件下的图像进行实验,结果表明该方法能对光照进行有效的补偿.     

A genetic algorithm approach to the multiple machine tool selection problem

A number of earlier researches have emphasized the on-the-job scheduling problems that occur with a single flexible machine. Two solutions to the problem have generally been considered; namely minimization of tool switches and minimization of tool switching instances. Methods used to solve the problems have included KTNS heuristic, dual-based relaxation heuristic, and non-LP-based branch-and-bound methods. However, scant literature has considered the case of job scheduling on multiple parallel machines which invokes another problem involving machine assignment. This paper addresses the problem of job scheduling and machine assignment on a flexible machining workstation (FMW) equipped with multiple parallel machines in a tool-sharing environment. Under these circumstances, the authors have attempted to model the problem with the objective of simultaneously minimizing both the number of tool switches and the number of tool switching instances. Furthermore, a set of realistic constraints has been included in the investigation. A novel genetic algorithm (GA) heuristic has been developed to solve the problem, and performance results show that GA is an appropriate solution.     

基于卡尔曼滤波的主动波浪补偿系统研究

针对船舶随涌浪进行的升沉运动进行较为深入的研究,旨在采用主动式波浪补偿解决耙吸式疏浚船耙管终端水平高度稳定问题。建立波浪补偿预测系统,通过运动参考单元测量船舶运动竖直方向速度和加速度,主控制单元根据所建立的数学模型结合卡尔曼滤波算法处理数据,通过执行机构调整绳索收放速度完成耙管终端控制补偿,使耙头水平高度在工作过程中保持稳定。所建立的波浪补偿预测系统具有自主学习能力,可以不断运用实测数据自我修正以提高精度,具有很高的实用价值。     

A hybrid fuzzy MCDM approach to machine tool selection

The selection of the appropriate machine tools for a manufacturing company is one of the important points to achieving high competitiveness in the market. Besides, an appropriate choice of machine tools is very important as it helps to realize full production quickly. Today’s market offers many more choices for machine tool alternatives. There are also many factors one should consider as part of the appropriate machine tool selection process, including productivity, flexibility, compatibility, safety, cost, etc. Consequently evaluation procedures involve several objectives and it is often necessary to compromise among possibly conflicting tangible and intangible factors. For these reasons, multiple criteria decision making (MCDM) has been found to be a useful approach to solve this kind of problem. Most of the MCDM models are basically mathematical and ignore qualitative and often subjective considerations. The use of fuzzy set theory allows incorporating qualitative and partially known information into the decision model. This paper describes a fuzzy technique for order preference by similarity to ideal solution (TOPSIS) based methodology for evaluation and selection of vertical CNC machining centers for a manufacturing company in Istanbul, Turkey. The criteria weights are calculated by using the fuzzy AHP (analytical hierarchy process).     

基于有限元的电容临近传感器研究

建立了电容临近传感器的三维仿真数学模型,用FEA对不同参数的传感器进行了仿真,比较分析了被测物距离、电极宽度、电极长度间隙比等对传感器灵敏度的影响,并与理论计算进行比较,结果表明:测量系统的灵敏度与电极宽度和电极长度间隙比近似成正比,与被测物距离近似成反比.该研究对电容临近传感器的结构设计有指导意义.     

A computer-aided design system for framed-mould in autoclave processing

The general computer-aided design (CAD) software cannot meet the mould design requirement of the autoclave process for composites, because many parameters such as temperature and pressure should be considered in the mould design process, in addition to the material and geometry of the part. A framed-mould computer-aided design system (FMCAD) used in the autoclave moulding process is proposed in this paper. A function model of the software is presented, in which influence factors such as part structure, mould structure, and process parameters are considered; a design model of the software is established using object oriented (0-0) technology to integrate the stiffness calculation, temperature field calculation, and deformation field calculation of mould in the design, and in the design model, a hybrid model of mould based on calculation feature and form feature is presented to support those calculations. A prototype system is developed, in which a mould design process wizard is built to integrate the input information, calculation, analysis, data storage, display, and design results of mould design. Finally, three design examples are used to verify the prototype.     

基于内容划分和运动补偿的视频质量评价

目前基于结构相似性的图像质量评价算法均是对图像进行整体质量分析,但人类视觉系统对图像中不同部分的敏感程度不同,而对图像进行整体质量分析无法有效反映出这些差异。鉴于此,提出了一种基于内容划分的图像质量评价算法,根据图像不同区域的梯度将图像分为四个部分,分别进行质量评价。之后,采用基于运动补偿的帧加权方式将上述方法扩展为视频质量评价。实验证明,所述算法与目前比较流行的几个算法相比具有较高的评价准确性。     

非线性复合邻域人脸光照补偿

变化的光照是提高人脸正确检测率的瓶颈,提出了非线性复合邻域光照补偿方法来解决人脸检测的光照问题。非线性复合邻域光照补偿方法用对数函数做为基函数,设置的平移系数和分界值系数可以同时对过亮和偏光的图像进行补偿,引入了邻域光照补偿公式解决了传统非线性方法不能针对同一灰度值像素在不同局部应该进行不同补偿的问题。实验结果表明,该方法对过暗和过亮的人脸图像都可以进行有效的光照补偿,熵比较优于传统非线性光照补偿、Gamma校正和直方图归一化。     

多传感器融合的数控机床热误差回归建模新方法

热误差对机床的加工精度影响很大,高性能的补偿系统依赖于多传感器融合建立的三维模型的精度、鲁棒性和合适的温度进行反馈输入。本文使用温度与位移传感器的模糊聚类进行温度分类,基于评价模型比对分析最优的温度分类,从每个分类中选择具有代表性温度作为候选温度。归纳试验数据,使用分段逆回归SIR模型进行热误差建模,SIR模型将高维前移回归问题转化为多个一维的回归问题,并且进一步消除了候选温度之间的耦合。热误差试验表明,SIR模型具有泛化能力强、预测精度高及鲁棒性好的特点,能够准确地描述多种典型工况条件下的实际热误差特性。     

电子罗盘最佳椭圆误差补偿方法

摘要：电子罗盘的方位数据可作为导航系统的初始位置数据,然而,电子罗盘在实际使用中极易受到外界磁场环境的影响而产生罗差,有效的减少罗差是提高导航系统初始位置精度的一项技术措施。本文研究了电子罗盘的最佳椭圆误差补偿方法,并把该算法应用到实际SINS-GPS组合导航初始对中,给出了实施方案和罗差补偿数据。实验验证,最佳椭圆误差补偿算法有效的消除了罗差,该罗盘可以应用于普通导航初始位置对准及其它领域。     

A monitor tool for a network based on the cambridge ring

An evolving network is subject to technological advances and increasing user demands through out its lifetime. Continuous monitoring is therefore required to understand its behaviour in the operational environment and to provide an aid to planning. A monitor tool has been developed to meet such requirements in a heavily used service network. A decentralized but integrated approach has been adopted. An active collection allows accumulated measurements to be retrieved. The measurements required are determined and the constraints imposed by existing mechanisms and the methods chosen are discussed. Flexible user facilities are available to allow selected measurements to be collected and displayed, and these are described. Daily sessions of network-wide monitoring have been undertaken. The overhead incurred is quantified. The sessions revealed communications software errors and anomalous behaviour of a network node. Further analysis shows the symptoms of the latter, the result of a hardware fault. Enhancements which would increase the flexibility of the tool are also suggested.     

基于漂移补偿的数字水印方法

在压缩的视频码流中嵌入数字水印时,如果选择在I帧图像的DCT系数中嵌入数字水印,那么后面的P帧和B帧图像的质量会受到很大的影响。提出了利用新的漂移补偿方法来减小I帧图像中的数字水印对后面的P帧图像和B帧图像的影响。实验结果证明该方法明显地提高了P帧和B帧图像质量,同时所需计算量较小。     

Computers and the Internet as a job assisted tool: based on the three-tier use model approach

Personal attitudes are a major factor to affect individual information technology usage. The purpose of this study is to explore the role of individual attitudes toward computers and the Internet usage for assisting job performance. This research applies the 3-TUM approach to understand individual attitudes toward computers and the Internet usage. After statistical analysis, the results provide a support that the 3-TUM is appropriate model for investigating faculty and staff perceptions toward computers and Internet. In addition, the results also support that using computers and the Internet may assist individual job performance. Furthermore; this study offer evidence that when individuals have more self-efficacy and feel computers and the Internet are more useful, then they have more behavioral intention to use and learn computers and the Internet for assisting their job performance.     

基于MEMS的微型手术器中的传感器

基于MEMS的微型手术器是一种可用于微创手术的新型医疗器械。这种手术器实际上是一种微型智能机器人 ,其中的传感器采用MEMS技术制造 ,具有微型、机电一体化集成、智能等特点。介绍了国际上具有代表性的微型手术器及其所采用的新传感技术 ,并探讨了这些传感器的发展和应用前景。     

基于Armlets的人脸光照补偿

提出了一种用于非均匀光照条件下人脸识别的光照补偿算法。该算法通过在对数域计算2维Armlets多小波变换来实现人脸光照补偿,然后直接在对数域进行人脸识别。在Yale B人脸库中与其他光照补偿算法进行了比较,实验结果表明,该方法的平均误识率仅为0.18%,优于现有的其他算法。     

A program design language based software maintenance tool

Program design languages are an increasingly important method of expressing the detailed design of a software system. Such languages can be modelled using a data structure known as a semantic net. This paper describes a maintenance tool for program design languages based on such a data structure. The tool allows the user to interrogate a semantic net using an interactive procedural language in order to derive information necessary for software maintenance. The technique upon which this tool is based is applicable to the maintenance of activities throughout the software lifecycle.     

An agent-based approach to tool integration

Tool integration is a very difficult challenge. Problems may arise at different abstraction levels and from several sources such as heterogeneity of manipulated data, incompatible interfaces, or uncoordinated services, to name just a few examples. On the other hand, applications based on the coherent composition of activities, components, services, and data from heterogeneous sources are increasingly present in our everyday lives. Consequently, tool integration takes on increasing significance.In this paper we analyze the tool-integration problem at different abstraction levels and discuss different views on a layered software architecture that we have designed specifically for a middleware that supports the execution of distributed applications for the orchestration of human/system activities. We noticed that the agent paradigm provided a suitable technology for abstraction in tool integration. Throughout the paper, the discussion refers to a case study in the bioinformatics domain.     

A group decision making framework based on fuzzy VIKOR approach for machine tool selection with linguistic information

Computer numerical control (CNC) machines are used for repetitive, difficult and unsafe manufacturing tasks that require a high degree of accuracy. However, when selecting an appropriate CNC machine, multiple criteria need to be considered by multiple decision makers. In this study, a multi-criteria group decision making (MCGDM) technique based on the fuzzy VIKOR method is developed to solve a CNC machine tool selection problem. Linguistic variables represented by triangular fuzzy numbers are used to reflect decision maker preferences for the criteria importance weights and the performance ratings. After the individual preferences are aggregated or after the separation values are computed, they are then defuzzified. In this paper, two algorithms based on a fuzzy linguistic approach are developed. Based on these two algorithms and the VIKOR method, a general MCGDM framework is proposed. A CNC machine tool selection example illustrates the application of the proposed approach. A comparative study of the two algorithms using the above case study information highlighted the need to combine the ranking results, as both algorithms have distinct characteristics.     

基于检修标准化的输电线路工器具配置系统

通过介绍输电线路安全运行的重要性,分析目前输电线路配置检修工器具的局限性。依据检修作用标准化分析了在复杂环境温度、风速、覆冰情况下检修/更换直线塔和耐张塔绝缘子串及金具类设备的工器具标准化配置的方法。运用Microsoft Visual Studio 2010开发环境下的C#和SQL Server 2008数据库设计开发了输电线路工器具智能配置系统,系统主要由用户管理、系统配置管理、工器具全生命周期管理和系统设置与维护组成,系统将弱化检修工器具配置对工作负责人的依赖,实现工器具配置的标准化、模块化、智能化作业,提高巡检作业的质量和科学管理技术水平。     

一种基于累积误差控制的RTC补偿算法及电路

介绍了晶体振荡器的温漂特性,提出了基于累积误差控制的RTC温度补偿算法,累积频率误差控制在15.3 ppm以内。设计了应用于微控制器中的RTC补偿电路,开发了自动调教电路,能很好地满足智能电表高精度、低功耗的计时要求。