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Theories and Methods of Non-optimum Analysis on Systems 被引量:2
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作者 HePing 《工程科学(英文版)》 2004年第1期73-80,共8页
The theory of non optimum analysis on systems were discussed in detail. It was pointed out that the main problem of exploring an indefinite systems’ optimum lies in the lack of non optimum analysis on the system. The... The theory of non optimum analysis on systems were discussed in detail. It was pointed out that the main problem of exploring an indefinite systems’ optimum lies in the lack of non optimum analysis on the system. The syndrome and empirical analysis based on the non optimum category of the system were established. At the same time, the non optimum measurement of the system along with non optimum tracing and self organization of the systems was also put forward. 展开更多
关键词 非最优化分析 系统自组织结构 非最优化测量 非最优化综合症 最优化系统 系统控制
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ON THE MINLP APPROACH FOR OPTIMAL DESIGN OF CHEMICAL ENGINEERING SYSTEMS(Ⅱ)SYNTHESIS OF DISTILLATION SEQUENCES
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作者 袁希钢 余国琮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1996年第1期42-51,共10页
In this paper the MINLP method proposed in Part(Ⅰ)is illustrated by applying it tothe synthesis problem of non-sharp distillation sequences.A MINLP formulation for the synthesis ofdistillation sequences with non-shar... In this paper the MINLP method proposed in Part(Ⅰ)is illustrated by applying it tothe synthesis problem of non-sharp distillation sequences.A MINLP formulation for the synthesis ofdistillation sequences with non-sharp separation is proposed.In this formulation the recoveries of thekey components are introduced as optimization variables and this makes it possible to synthesize adistillation sequence with specified component recoveries,and at the same time,renders the MINLPproblem nonconvex.The solution procedure is illustrated with three example problems. 展开更多
关键词 non-sharp DISTILLATION SEQUENCES MINLP FORMULATION optimum synthesis
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Added Resistance Acting on Hull of a Non Ballast Water Ship 被引量:2
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作者 Ngo Van He Yoshiho Ikeda 《Journal of Marine Science and Application》 2014年第1期11-22,共12页
In this paper, added resistances acting on a hull of non ballast water ship(NBS) in high waves is discussed. The non ballast water ships were developed at the laboratory of the authors at Osaka Prefecture University, ... In this paper, added resistances acting on a hull of non ballast water ship(NBS) in high waves is discussed. The non ballast water ships were developed at the laboratory of the authors at Osaka Prefecture University, Japan. In the present paper, the performances of three kinds of bow shapes developed for the NBS were theoretically and experimentally investigated to find the best one in high waves. In previous papers, an optimum bow shape for the NBS was developed in calm water and in moderated waves. For a 2 m model for experiments and computations, the wave height is 0.02 m. This means that the wave height is 15% of the draft of the ship in full load conditions. In this paper, added resistances in high waves up to 0.07 m for a 2 m model or 53% of the full load draft are investigated. In such high waves linear wave theories which have been used in the design stage of a ship for a long time may not work well anymore, and experiments are the only effective tool to predict the added resistance in high waves. With the computations for waves, the ship is in a fully captured condition because shorter waves, λ/Lpp<0.6, are assumed. 展开更多
关键词 added resistance non ballast water ship HULL optimum bow shape
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Investigation of Micro-wear and Micro-friction Properties for Bionic Non-smooth Concave Components 被引量:2
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作者 HanZhi-wu XuXiao-xia +1 位作者 QiuZhao-mei RenLu-quan 《Journal of Bionic Engineering》 SCIE EI CSCD 2005年第2期63-67,共5页
Five kinds of 45# steel samples with concave features on the surface were manufactured using Laser Texturing Technology (LTT). Optimum design theory was used to design the experiment, and a two-level orthogonal table-... Five kinds of 45# steel samples with concave features on the surface were manufactured using Laser Texturing Technology (LTT). Optimum design theory was used to design the experiment, and a two-level orthogonal table-L 16 (2 15 ) design was adopted . Micro-wear and micro-friction experienced by samples with concave surface features and samples with smooth surfaces were compared experimentally. The wear resistance of samples with concave surface features was increased most, and different surface morphologies had different effects on friction and wear properties. 展开更多
关键词 bionic non-smoothness experiment optimum FRICTION WEAR ANTI-WEAR
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Optimal Placement of Reclosers to Minimize Power Losses during Non-Load Bearing Disturbances in a Power Distribution Using Firefly Algorithm
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作者 Wyclife Odongo Amolo Peter Musau Abraham Nyete 《Journal of Power and Energy Engineering》 2021年第5期63-75,共13页
The research reported in this paper focuses on non-technical power loss reduction for power distribution systems. Such reduction of costs of energy not served (ENS.COST), is intelligently evaluated and optimized using... The research reported in this paper focuses on non-technical power loss reduction for power distribution systems. Such reduction of costs of energy not served (ENS.COST), is intelligently evaluated and optimized using a firefly algorithm, from where savings of 43.3% on energy not served are achieved. 展开更多
关键词 Loss Minimization non-Load Bearing Power Losses optimum Location Reclosers Transient Power Balance
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Fuzzy Geometric Programming in Multivariate Stratified Sample Surveys in Presence of Non-Response with Quadratic Cost Function
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作者 Shafiullah   Mohammad Faisal Khan Irfan Ali 《American Journal of Operations Research》 2014年第3期173-188,共16页
In this paper, the problem of non-response with significant travel costs in multivariate stratified sample surveys has been formulated of as a Multi-Objective Geometric Programming Problem (MOGPP). The fuzzy programmi... In this paper, the problem of non-response with significant travel costs in multivariate stratified sample surveys has been formulated of as a Multi-Objective Geometric Programming Problem (MOGPP). The fuzzy programming approach has been described for solving the formulated MOGPP. The formulated MOGPP has been solved with the help of LINGO Software and the dual solution is obtained. The optimum allocations of sample sizes of respondents and non respondents are obtained with the help of dual solutions and primal-dual relationship theorem. A numerical example is given to illustrate the procedure. 展开更多
关键词 Geometric PROGRAMMING FUZZY PROGRAMMING non-RESPONSE with Travel Cost optimum ALLOCATIONS MULTIVARIATE STRATIFIED Sample Surveys
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初中数学教科书非文本元素特点及功能研究——以浙教版为例 被引量:3
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作者 李玲珠 陈秋雨 《数学教育学报》 CSSCI 北大核心 2024年第1期8-15,43,共9页
非文本元素是数学教科书不可或缺的组成部分.但有研究者发现,部分NTEs存在偏装饰、功能单一、与数学联系不紧密的现象.以浙教版初中数学教材为例,通过比较NTEs的类别与功能分析其合理性.研究发现,浙教版八年级的NTEs数量最多,九年级平... 非文本元素是数学教科书不可或缺的组成部分.但有研究者发现,部分NTEs存在偏装饰、功能单一、与数学联系不紧密的现象.以浙教版初中数学教材为例,通过比较NTEs的类别与功能分析其合理性.研究发现,浙教版八年级的NTEs数量最多,九年级平均密度最大.类别与功能上,NTEs在数学类的数量最多,以解释性功能为主.此外,生活类的NTEs以装饰性功能为主,数学史类NTEs以装饰性和解释性功能为主.未来,NTEs可在与数学内容的实质性联系以及功能的丰富性上作进一步考虑. 展开更多
关键词 浙教版 非文本元素 类别 功能 教材分析
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基于多空气槽新V型转子超高效NVRPM优化设计
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作者 刘鑫 王步来 苑宇阳 《机床与液压》 北大核心 2024年第3期136-142,共7页
依据指标优化设计一款额定功率22 kW、额定转速3000 r/min的压缩机用内置新V型转子永磁同步电机(NVRPM)。由于V型结构永磁电机较多的永磁体块数造成转子极间漏磁增大,以及气隙磁场含有较大的谐波分量易导致损耗增加、效率降低,在初始V... 依据指标优化设计一款额定功率22 kW、额定转速3000 r/min的压缩机用内置新V型转子永磁同步电机(NVRPM)。由于V型结构永磁电机较多的永磁体块数造成转子极间漏磁增大,以及气隙磁场含有较大的谐波分量易导致损耗增加、效率降低,在初始V型转子上进行3处结构的优化设计:转子面上添加多空气槽;余弦型非均匀气隙;转子分段斜极式。通过有限元仿真NVRPM的电磁特性,并且计算最佳斜极角、分析非均匀气隙中余弦函数的幅值,证明优化后新电机能够减少损耗22.6%、削弱齿槽转矩98.2%、降低转矩波动11.7%。另外,试制实验样机并测试效率高达96.32%且运行区域宽广高效。因此NVRPM的优化设计具有实践性,适合压缩机生产使用。 展开更多
关键词 新V型转子电机(NVRPM) 多空气槽 余弦型非均匀气隙 最佳斜极角 优化设计
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Study on Mandatory Access Control in a Secure Database Management System
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作者 ZHU Hong, FENG Yu cai School of Computer Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China 《Journal of Shanghai University(English Edition)》 CAS 2001年第4期299-307,共9页
This paper proposes a security policy model for mandatory access control in class B1 database management system whose level of labeling is tuple. The relation hierarchical data model is extended to multilevel relatio... This paper proposes a security policy model for mandatory access control in class B1 database management system whose level of labeling is tuple. The relation hierarchical data model is extended to multilevel relation hierarchical data model. Based on the multilevel relation hierarchical data model, the concept of upper lower layer relational integrity is presented after we analyze and eliminate the covert channels caused by the database integrity. Two SQL statements are extended to process polyinstantiation in the multilevel secure environment. The system is based on the multilevel relation hierarchical data model and is capable of integratively storing and manipulating multilevel complicated objects ( e.g., multilevel spatial data) and multilevel conventional data ( e.g., integer, real number and character string). 展开更多
关键词 multilevel relation hierarchical data model covert channels mandatory access control POLYINSTANTIATION hierarchical classification non hierarchical category security level multilevel relation hierarchical instance INTEGRITY cluster
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Non-equal-interval direct optimizing Verhulst model that x(n) be taken as initial value and its application 被引量:2
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作者 Luo, Youxin Chen, Mianyun +1 位作者 Che, Xiaoyi He, Zheming 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期17-21,共5页
To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) ... To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) of X(0) as the starting condition of the grey differential model. It optimizes a modified β value and the background value, and takes two times fitting optimization. The new model extends equal intervals to non-equal-intervals and is suitable for general data modelling and estimating parameters of the direct Verhulst GM(1,1). The new model does not need to pre-process the primitive data, nor accumulate generating operation (AGO) and inverse accumulated generating operation (IAGO). It is not only suitable for equal interval data modelling, but also for non-equal interval data modelling. As the new information is fully used and two times fitting optimization is taken, the fitting accuracy is the highest in all existing models. The example shows that the new model is simple and practical. The new model is worth expanding on and applying in data processing or on-line monitoring for tests, social sciences and other engineering sciences. 展开更多
关键词 grey system data processing Verhulst GM(1 1) non-equal interval direct modelling optimum background value two times fitting
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OFDM信号功率放大器的最佳预校正曲线 被引量:1
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作者 陈瑶华 蔡超时 陈群 《广播与电视技术》 2017年第10期103-107,共5页
正交频分复用调制(OFDM)技术中,多载波信号峰均比高,覆盖其动态范围的功放代价难以接受,经过功率放大器(HPA)时会超过放大器的动态范围,此时放大器的最佳预校正曲线已不再是反函数曲线,合成曲线也不再是线性折线。实际的预校正曲线取决... 正交频分复用调制(OFDM)技术中,多载波信号峰均比高,覆盖其动态范围的功放代价难以接受,经过功率放大器(HPA)时会超过放大器的动态范围,此时放大器的最佳预校正曲线已不再是反函数曲线,合成曲线也不再是线性折线。实际的预校正曲线取决于多载波信号的幅度分布曲线CCDF。本文提出的HPA预校正函数曲线方法考虑到放大器中每个子载波的对失真的影响,限定放大器输入功率回退(IBO)条件下获得尽可能高的MER。其校正效果相较于反函数曲线可获得9.5d B的MER功放性能改善,进而说明反函数法并不能使预失真效果达到最优,最后文中给出最佳预校正及功率放大器的合成曲线。 展开更多
关键词 功率放大器 反函数曲线 非线性失真 最佳预校正曲线
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复杂非均质场地中核安全抗震Ⅰ类桩基结构楼层反应谱研究 被引量:1
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作者 王海龙 隋春光 +2 位作者 靳金平 杨建华 李小军 《建筑结构》 北大核心 2023年第S01期688-694,共7页
近年来随着核工程领域的快速发展,理想的基岩厂址越来越少,核工程建设场址选择逐渐由基岩场地向非基岩场地过渡将成为必然趋势。传统的技术方案已经不能满足抗震Ⅰ类结构对地基的要求,为了保障核工程的可持续发展,地基问题亟待解决。桩... 近年来随着核工程领域的快速发展,理想的基岩厂址越来越少,核工程建设场址选择逐渐由基岩场地向非基岩场地过渡将成为必然趋势。传统的技术方案已经不能满足抗震Ⅰ类结构对地基的要求,为了保障核工程的可持续发展,地基问题亟待解决。桩基技术在一般的工业与民用建筑领域的应用已经十分广泛和成熟,由于核工程的特殊性,民用桩基规范中相关标准难以解决核工程桩基面临的技术难题,进而限制了桩基在核工程领域的应用。制约桩基在核安全抗震Ⅰ类结构上应用的主要技术难题是桩-土-结构动力相互作用问题。选取国内首个位于复杂软土地基上的核安全抗震Ⅰ类结构,首先采用国内外规范中认可度较高的p-y曲线法,分析了桩-土-结构体系的地震动力响应,获得了楼层反应谱和各项动力性能指标,然后采用三维完全法验证了p-y曲线法的保守性。在国内首次采用桩基础解决了实际工程中核安全抗震Ⅰ类结构地基问题,为桩基础在核工程领域的推广和应用提供了有价值的参考,对于进一步拓展核工程厂址的选址范围具有重要意义。 展开更多
关键词 非均质场地 抗震Ⅰ类 桩基础 P-Y曲线法 三维完全法
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民刑衔接视阈下非同质化通证的法益证成与刑事归责思考 被引量:6
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作者 王霖 《政治与法律》 CSSCI 北大核心 2023年第4期67-83,共17页
非同质化通证的实践化过程存在刑事风险外溢的可能,既有数字通证监管体系并未于法规范层面提供界定其法律性质的直接依据。民法学领域衍生的“传统权利界定方案”与“新型权利构建方案”虽各存弊端,但也都有启示价值。对此应以民刑衔接... 非同质化通证的实践化过程存在刑事风险外溢的可能,既有数字通证监管体系并未于法规范层面提供界定其法律性质的直接依据。民法学领域衍生的“传统权利界定方案”与“新型权利构建方案”虽各存弊端,但也都有启示价值。对此应以民刑衔接为逻辑指引,承接“权利块”结构的权利多元化、标准化安排,于缓和违法一元论立场上对非同质化通证进行刑事法益内涵的双层确立,其中载体层法益与刑法“占有”保护形成对接关系,映射层法益应结合实践化场景个别化考察。以当前国内非同质化通证的数字艺术品交易为问题聚焦,刑事归责路径应围绕个体参与行为与平台服务行为展开,前者立足于非同质化通证双层法益结构进行判断,后者置于不作为向度契合平台差异进行“内容审查义务”与“安全监管义务”的类型化构建,以此实现非同质化通证刑事归责范围的理性界定。 展开更多
关键词 非同质化通证 数字艺术品 权利块 法益类型 作为义务
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压力容器凸缘焊接接头类别及无损检测问题关键技术研究 被引量:2
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作者 袁承春 《化工设备与管道》 CAS 北大核心 2023年第5期12-16,共5页
论述了长期以来工程实践中存在的与壳体对接接头连接的凸缘焊接接头分类以及无损检测问题。对压力容器凸缘焊接接头存在的A类和D类接头争议和嵌入式凸缘的错误观点对我国压力容器产品质量和安全可靠性造成的不良影响进行了全面的分析和... 论述了长期以来工程实践中存在的与壳体对接接头连接的凸缘焊接接头分类以及无损检测问题。对压力容器凸缘焊接接头存在的A类和D类接头争议和嵌入式凸缘的错误观点对我国压力容器产品质量和安全可靠性造成的不良影响进行了全面的分析和探讨,提出了独到的见解,攻克了困扰我国压力容器装备设计、制造、焊接和无损检测领域多年的关键技术疑难问题,推动了我国压力容器装备设计、制造和产品质量的提高和科技的进步。 展开更多
关键词 压力容器 凸缘 设计 制造 焊接 焊接接头类别 无损检测 关键技术
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改进NSGA-Ⅱ算法的海上搜救调度方法
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作者 严梦迪 王海红 《计算机系统应用》 2023年第8期244-249,共6页
针对海上搜救资源调度决策困难、干扰多、实时性差、难以实现全局最优问题,本文以黄渤海海域为例,采用改进的非支配排序遗传(NSGA-Ⅱ)算法解决海上船舶搜救资源调度问题.首先,根据AIS以及北斗数据,建立了海上搜救资源的多目标优化模型;... 针对海上搜救资源调度决策困难、干扰多、实时性差、难以实现全局最优问题,本文以黄渤海海域为例,采用改进的非支配排序遗传(NSGA-Ⅱ)算法解决海上船舶搜救资源调度问题.首先,根据AIS以及北斗数据,建立了海上搜救资源的多目标优化模型;其次,改进的NSGA-Ⅱ算法采用基于正态分布交叉(NDX)算子,在扩大搜索范围的基础上,避免陷入局部最优,得到多目标问题完整的Pareto解集;采用综合评价法(TOPSIS)从Pareto解集中求得折衷解,即最终设计的搜救调度方案;最后,在考虑船舶数量约束以及时间约束的条件下,采用改进的NSGA-Ⅱ算法分别与NSGA-Ⅱ算法和贪婪算法进行对比,并采用黄渤海海域船舶采集数据进行仿真.结果表明该算法能够有效解决海上搜救资源调度优化问题. 展开更多
关键词 改进的非支配排序遗传 多目标优化模型 海上搜救 调度优化 全局最优
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一种絮凝剂对C30水下不分散混凝土的影响 被引量:1
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作者 郑龙龙 仲伟秋 +2 位作者 李武绪 曹聪 曾令伟 《低温建筑技术》 2023年第2期35-39,共5页
为探明UWB-Ⅱ型絮凝剂的不同掺量对C30水下不分散混凝土各项性能的影响规律,研究影响机理,并确定最佳掺量。分别选取了五组掺量进行流动性试验、抗分散性试验及抗压试验。结果表明絮凝剂自身的各种亲水基团会降低混凝土的流动性。当絮... 为探明UWB-Ⅱ型絮凝剂的不同掺量对C30水下不分散混凝土各项性能的影响规律,研究影响机理,并确定最佳掺量。分别选取了五组掺量进行流动性试验、抗分散性试验及抗压试验。结果表明絮凝剂自身的各种亲水基团会降低混凝土的流动性。当絮凝剂掺量增大时,试验水样的悬浊物含量、pH值及浊度值均反向变化。在絮凝剂掺量为2.5%时,试件抗压强度达到最大。随着絮凝剂掺量继续增加,材料的抗压强度出现下降。总结分析UWB-Ⅱ型絮凝剂在C30水下不分散混凝土中的最佳掺量应为2.5%。 展开更多
关键词 水下不分散混凝土 絮凝剂 最佳掺量
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The Category of Humanity: Language as a Reflection of the Opposition between the Natural Sphere and the Human Sphere
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作者 Enrique J.Vercher García 《Language and Semiotic Studies》 2019年第2期37-52,共16页
The article analyses the way in which human languages classify reality into two large categories: the natural sphere and the human sphere. Thus, a given language will use the resources of its different linguistic leve... The article analyses the way in which human languages classify reality into two large categories: the natural sphere and the human sphere. Thus, a given language will use the resources of its different linguistic levels(phonetic-phonological, morphological, syntactic, and lexical) to configure the references of reality and classify them based on what the speaker considers as belonging to the sphere of human society or the sphere of nature, outwith the human community. The same object, animal, phenomenon, or event may be treated(and evaluated) differently depending on whether the speakers of a given language consider it as belonging to the human sphere or the natural sphere. 展开更多
关键词 LINGUISTICS cognitive LINGUISTICS LINGUISTIC ANTHROPOLOGY linguoculturology natural languages LINGUISTIC categories human/non-human
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二维PSD非线性修正共轭梯度算法 被引量:12
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作者 莫长涛 陈长征 +1 位作者 张黎丽 孙凤久 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2003年第5期507-509,共3页
根据光电位置敏感器件的原理和光点位置方程分析了PSD的非线性成因,并根据PSD的非线性特点,提出用神经网络的共轭梯度算法对PSD的非线性进行补偿·利用神经网络共轭梯度算法具有逼近任意非线性函数的特点,通过神经网络建立PSD实际... 根据光电位置敏感器件的原理和光点位置方程分析了PSD的非线性成因,并根据PSD的非线性特点,提出用神经网络的共轭梯度算法对PSD的非线性进行补偿·利用神经网络共轭梯度算法具有逼近任意非线性函数的特点,通过神经网络建立PSD实际输出与其理想值之间的非线性映射关系,实现光电位置敏感器件非线性补偿·计算机仿真表明,该方法不仅能有效地消除非线性的影响,而且在神经网络的输出端得到期望的线性输出·从而使PSD的B区获得了与A区近似的线性度,故在不增加成本,不改变测量设备复杂度的情况下,扩大了测量范围,提高了B区的测量准确度及数据的置信度· 展开更多
关键词 光电位置敏感器件 补偿 非线性修正 神经网络 共轭梯度法
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无螺栓十字轴万向联轴器结构形状优化设计 被引量:6
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作者 柯尊忠 张宏梅 +1 位作者 黄康 王卫荣 《合肥工业大学学报(自然科学版)》 CAS CSCD 2000年第1期91-94,共4页
文章以轧钢机上的无螺栓十字轴万向联轴器为例 ,建立三维有限元分析模型 ,并进行静力分析 ,找出叉头的应力集中区和最大应力值。为了使叉头的最大应力减小 ,提高叉头强度及结构的工艺性 ,对叉头的内轮廓进行形状优化设计 ,提出了一种简... 文章以轧钢机上的无螺栓十字轴万向联轴器为例 ,建立三维有限元分析模型 ,并进行静力分析 ,找出叉头的应力集中区和最大应力值。为了使叉头的最大应力减小 ,提高叉头强度及结构的工艺性 ,对叉头的内轮廓进行形状优化设计 ,提出了一种简单的“圆弧 -直线 -圆弧”型的曲线来作为叉头的内轮廓曲线 ,并利用复合形法进行优化设计 ,得到最优的叉头结构参数。 展开更多
关键词 无螺栓十字轴万向联轴器 轧钢机 三维有限元分析 叉头 应力 优化设计
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