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  • Steering control of a capsule robot in curve environment by magnetic navigation is not yet solved completely.A petal-shaped capsule robot with less steering resistance based on multiple wedge effects is presented,and an optimization method with two processes for determining the orientation of a pre-applied universal magnetic spin vector is proposed.To realize quick and non-contact steering swimming,a fuzzy comprehensive evaluation method for optimizing the steering driving angle is presented based on two evaluation indexes including the average steering speed and the average steering trajectory deviation,achieving the initial optimal orientation of a universal magnetic spin vector.To further reduce robotic magnetic vibration,a main target method for optimizing its final orientation,which is used for fine adjustment,is employed under the constrains of the magnetic moments.Swimming experimental results in curve pipe verified the effectiveness of the optimization method,which can be effectively used to realize non-contact steering swimming of the petal-shaped robot and reduce its vibration.
     - 中国机械工程学报
    文章来源: 万方数据
  • 物流企业竞争力的模糊综合评价

    以我国物流企业竞争力评价为总目标,建立相应的竞争力评价指标体系,通过运用层次分析法确定了各层次指标权重,在此基础上根据模糊综合评价方法实证评价了物流企业的竞争力,为物流企业合理配置资源和提高自身竞争力提供理论参考和有价值的思路.
    任建美 - 物流技术
    文章来源: 万方数据
  • 基于组合权重的绿色度三角模糊函数模糊综合评价研究

    首先建立了一套生产型节点企业绿色度综合评价指标体系,然后综合运用熵权值法、德尔菲法、层次分析法、三角模糊函数法形成的模糊综合评价方法对绿色度的评价问题进行研究,提出了基于组合权重的三角模糊函数模糊综合评价方法及其完整的评价过程,最后以供应链上多家企业的实际数据为例进行了实证研究.
    高本河,贺巍巍,郑力 - 物流技术
    文章来源: 万方数据
  • The existing researches of the evaluation method of ride comfort of vehicle mainly focus on the level of human feelings to vibration. The level of human feelings to vibration is influenced by many factors, however, the ride comfort according to the common principle of probability and statistics and simple binary logic is unable to reflect these uncertainties. The random fuzzy evaluation model from people subjective response to vibration is adopted in the paper, these uncertainties are analyzed from the angle of psychological physics. Discussing the traditional evaluation of ride comfort during vehicle vibration, a fuzzily random evaluation model on the basis of annoyance rate is proposed for the human body's subjective response to vibration, with relevant fuzzy membership function and probability distribution given. A half-car four degrees of freedom suspension vibration model is described, subject to irregular excitations from the road surface, with the aid of software Matlab/Simulink. A new kind of evaluation method for ride comfort of vehicles is proposed in the paper, i.e., the annoyance rate evaluation method. The genetic algorithm and neural network control theory are used to control the system. Simulation results are obtained, such as the comparison of comfort reaction to vibration environments between before and after control, relationship of annoyance rate to vibration frequency and weighted acceleration, based on ISO2631/1(1982), ISO 2631–1(1997) and annoyance rate evaluation method, respectively. Simulated assessment results indicate that the proposed active suspension systems prove to be effective in the vibration isolation of the suspension system, and the subjective response of human being can be promoted from very uncomfortable to a little uncomfortable. Furthermore, the novel evaluation method based on annoyance rate can further estimate quantitatively the number of passengers who feel discomfort due to vibration. A new analysis method of vehicle comfort is presented.
     - 中国机械工程学报
    文章来源: 万方数据
  • 运用Excel进行物流信息化模糊综合评价

    通过分析物流信息化的涵义,在遵循指标体系构建原则基础上设计物流信息化评价指标体系,将层次分析法与模糊综合评价法结合起来进行客观评价,并且巧妙运用Excel计算表进行求解.
    邢宗新 - 物流技术
    文章来源: 万方数据
  • Pneumatic actuators and electric actuators have almost been applied to all manufacturing industries.The two kinds of actuators can replace each other in most fields,such as the point to point transmission occasion and some rotating occasions.However,there are very few research results about the advantages and disadvantages of two kinds of actuators under the same working conditions so far.In this paper,a novel comprehensive assessment method,named as overall life cycle comprehensive assessment(OLCCA),is proposed for comparison and assessment of pneumatic and electric actuators.OLCCA contains mechanical properties evaluation(MPE),life cycle cost analysis based on users(LCCABOU)and life cycle environmental impact analysis(LCEIA)algorithm in order to solve three difficult problems:mechanical properties assessment,cost analysis and environmental impact assessment about actuators.The mechanical properties evaluation of actuators is a multi-objective optimization problem.The fuzzy data quantification and information entropy methods are combined to establish MPE algorithm of actuators.Two kinds of pneumatic actuators and electric actuators with similar bearing capacity and similar work stroke were taken for example to verify the correctness of MPE algorithm.The case study of MPE algorithm for actuators verified its correctness.LCCABOU for actuators is also set up.Considering cost complex structure of pneumatic actuators,public device cost even method(PDCEM)is firstly presented to solve cost division of public devices such as compressors,aftercooler,receivers,etc.LCCABOU method is also effective and verified by the three groups of pneumatic actuators and electric actuators.Finally,LCEIA model of actuators is established for the environmental impact assessment of actuators.LCEIA data collection method and model establishment procedure for actuators are also put forward.With Simapro 7,LCEIA comparison results of six actuators can be obtained:Fossil fuels are the major environmental factor of pneumatic and electric actuators;Environmental impact of electric actuator is large than one of pneumatic actuator under the similar mechanical properties and working conditions of pneumatic and electric actuators.The results are correct and correspond with the actual mechanical properties of actuators.This paper proposes a comprehensive evaluation method of the actuators,which can solve the critical problem that similar electromechanical products are very difficult to be compared with each other from the angle of performance,cost and environment impact.
     - 中国机械工程学报
    文章来源: 万方数据
  • 模糊综合评价法在民心河水质评价中的应用

    为提高石家庄市民心河水质预测的精度和实用性,对石家庄市民心河水样进行了检测,利用模糊综合评价法对水质污染现状进行了评价,得出民心河大部分水样监测点水质都在V类,部分指标超出了景观用水水质标准,河水受到污染.因此需要采取措施改善水环境质量.
    石兆英,郑艳侠,杨建强,果新巧 - 南水北调与水利科技
    文章来源: 万方数据
  • 基于三大检索系统收录论文对地方高等院校科研水平与学科发展的评价研究

    基于SCI-E(即SCI网络版)、Ei和ISTP这三大数据库,对浙江省25所本科院校在2006-2010年5年间被收录的论文,运用文献计量法对论文数量、收录论文的年度、学科分布和院校排名进行统计与分析,通过定量数据反映地方高校的科研水平和学科发展,为地方高校的科研评估、学科建设提供数据参考.也为高校图书馆拓展信息服务内容进行有益探索.
    隋秀芝,李炜 - 中国高教研究
    文章来源: 万方数据
  • 开放存取论文开放评价方法

    分析传统学术论文和开放存取论文现有评价方法的不足与困难之处;融合层次分析法和同行评议所具有的优势,提出开放存取论文评价的框架、流程以及具体实现方法.最后通过实验验证其评价效果,结果显示该方法的评价结果与文章的真实值相近.
    尹天久,宗乾进,袁勤俭 - 图书情报工作
    文章来源: 万方数据
  • Iterative methods based on finite element simulation are effective approaches to design mold shape to compensate springback in sheet metal forming.However,convergence rate of iterative methods is difficult to improve greatly.To increase the springback compensate speed of designing age forming mold,process of calculating springback for a certain mold with finite element method is analyzed.Springback compensation is abstracted as finding a solution for a set of nonlinear functions and a springback compensation algorithm is presented on the basis of quasi Newton method.The accuracy of algorithm is verified by developing an ABAQUS secondary development program with MATLAB.Three rectangular integrated panels of dimensions 710 mm′750 mm integrated panels with intersected ribs of 10 mm are selected to perform case studies.The algorithm is used to compute mold contours for the panels with cylinder,sphere and saddle contours respectively and it takes 57%,22%and 33%iterations as compared to that of displacement adjustment(DA)method.At the end of iterations,maximum deviations on the three panels are 0.618 4 mm,0.624 1 mm and 0.342 0 mm that are smaller than the deviations determined by DA method(0.740 8 mm,0.740 8 mm and 0.713 7 mm respectively).In following experimental verification,mold contour for another integrated panel with 400 mm*380 mm size is designed by the algorithm.Then the panel is age formed in an autoclave and measured by a three dimensional digital measurement devise.Deviation between measuring results and the panel's design contour is less than 1 mm.Finally,the iterations with different mesh sizes(40 mm,35mm,30 mm,25 mm,20 mm)in finite element models are compared and found no considerable difference.Another possible compensation method,Broyden-Fletcher-Shanmo method,is also presented based on the solving nonlinear functions idea.The Broyden-Fletcher-Shanmo method is employed to compute mold contour for the second panel.It only takes 50%iterations compared to that of DA.The proposed method can serve a faster mold contour compensation method for sheet metal forming.
     - 中国机械工程学报
    文章来源: 万方数据
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