21 research outputs found

    基于急转弯工况下的电动车车架有限元分析

    Get PDF
    以国内某一种型号的电动车车架为研究对象,利用有限元分析软件AnSyS,合理建立车架有限元简化模型,对电动车满载紧急转弯工况进行了车架静态特性分析,得出相应工况下应力分布和变形云图,为后续的汽车安全设计和车架优化设计提供了参考依据。福建省科技计划重大产学研项目(No.2010H6028);福建省科技计划重点项目(No.2009I0027);福建省教育厅A类科技计划项目(No.JA10245);厦门市科技计划高校创新项目(No.3502Z20083027

    导览车AFS偏转规律的研究

    Get PDF
    自适应前照明系统(AdAPTIVE frOnT-lIgHTIng SySTEMS,以下简称AfS),是一种能在各种环境下,给出最佳照明方式的智能前照灯系统,为夜间驾驶员的安全驾驶提供了有力保障。通过对金厦电动导览车AfS的数学建模和分析,依据导览车的自身参数和特点来研究导览车AfS的偏转规律,并着重分析导览车悬架对其AfS偏转规律的影响

    基于FLUENT的盘型塑件高光模具热响应研究

    Get PDF
    采用高温高压水加热水冷却的方式对盘型塑件型腔表面进行模温变换,以实现塑件表面的高光泽度效果。建立不同工况下的变模温注塑模型,并利用fluEnT流体力学软件模拟其加热响应,通过对比分析,获取其最佳的工艺参数。福建省科技计划重大产学研项目(No.2010H6028);福建省科技计划重点项目(No.2009I0027);福建省教育厅A类科技计划项目(No.JA10245);厦门市科技计划高校创新项目(No.3502Z20083027

    Image retrieval based on SIFT features

    Get PDF
    提出一种多尺度图像检索算法,该算法基于SIFT特征提取,它将一幅图像转换成特征向量的集合,图像间的相似距离是通过计算两幅图像特征向量间的欧氏距离来实现的。实验结果很好地说明了该算法具有尺度、平移、旋转不变性,一定的仿射、光照不变性以及算法能很好地应用在特定形状特征目标的检索中。This paper presented a new image retrieval algorithm which used a new class of image features as the image descriptors,the SIFT features.It transformed the image into a set of SIFT features.The similarity was computed using Euclidean distance.Experiments show that the features are invariant to image scaling,translation,rotation,and change in viewpoint,and partially invariant to illumination changes and affine.It is quite applicable to typical image retrieval.国家自然科学基金资助项目(60373080);; 厦门大学“985”二期信息技术创新平台资助项目(2004-2007);; 厦门大学院士启动基金资助项

    Regional Disparity,Affecting Factors and Convergence Analysis of Carbon Dioxide Emission Efficiency in China:On Stochastic Frontier Model and Panel Unit Root

    No full text
    中国政府在“十二五“规划中明确提出了二氧化碳减排的目标,由此引来的亟待解决的问题是:在促进结构调整的同时如何兼顾落后地区的发展空间?客观地评估和分析我国不同地区二氧化碳排放效率的现状,趋势及其影响因素是解决这一问题的先决条件。本文在随机前沿边界分析框架下,直观地定义并测算了碳排放效率,然后对我国1995~2009年各个地区的碳排放效率进行测算,并对地区差异、影响因素及收敛性进行分析。研究结果表明碳排放效率存在比较大的地区差异,而且这种差异还会不断扩大,地区差异始终是我国减排政策实践中应当考虑的因素。此外,发挥市场的资源配置作用、城市化进程、清洁能源的替代、出口贸易的发展等对我国碳排放效率的提高有积极的促进作用。Chinese government proclaimed a target of the reduction of carbon dioxide emission in the 12th Five-Year Plan,which led the urgent problem how to give consideration on the development of less developed areas while concentrating on promoting the structural adjustment.It is a requirement of the problem that objectively evaluates and analyzes the present situation,the trend and the affecting factors of carbon dioxide emission efficiency in different areas in China.Under the framework of stochastic frontier analysis,this paper directly defined the carbon emission efficiency,measured the carbon emission efficiency in each area of China from 1995to 2009,and analyzed the regional disparity, affecting factors and convergence.The results show that carbon emission efficiency has obvious regional disparity,which may continue to expend,and always is a factor should be considered in the practice of China's reduction policy.In addition,resource allocation,urbanization,clean energy substitution,export trade development have positive effects on the promotion of carbon emission efficiency.中央高校基本科研业务费专项资金(项目编号:201122G008)资

    End force tracking control algorithm of grinding robot based on model predictive control

    No full text
    磨削机器人因其快速、高效的优点在工业磨削行业应用广泛。磨削机器人末端力控制与其磨削质量有着直接关系。基于曲面预测与模型预测控制算法提出磨削机器人对连续曲面工作时的末端力控制算法。给出了机械臂离散、线性化的动力学模型;根据曲面预测算法计算未来时刻的曲面坐标,通过快速算法和求逆解运算获得机械臂满足设定值时各关节的期望角度;由动态矩阵控制(DMC)算法求得机械臂各关节的输入力矩,以实现对期望关节角的轨迹跟踪。最后采用实验仿真进行验证,证明了机械臂针对未知曲面作业时所提算法力控制的实时有效性

    Topology Optimization on Bracket Side Panel of Beach Cleaner's Dumping Device

    No full text
    Conference Name:International Symposium on Manufacturing Systems Engineering (ISMSE 2011). Conference Address: Hong Kong, PEOPLES R CHINA. Time:SEP 17-18, 2011.According to the typical working conditions of beach cleaner, which come from the result of the virtual prototyping model's simulation analysis. Establish the optimal topology design of the bracket side panel of the dumping device by ANSYS software. Compare the results before and after optimization, we conclude that, the bracket side panel has been not only reduce by 17.1% in mass under meeting the strength and rigidity requirements but also improved its welding technology. At the same time, this paper can provide reference for the lightening design and manufacturability improvement of complex loading parts

    基于p~2不变量的图象检索

    No full text
    基于内容的视觉信息检索是由于视觉信息的飞速膨胀而得到关注并被提出来的。现代的基于内容的视觉信息检索算法通常存在一个重要的不足:算法常随着图象的平移、旋转、尺度等变化,准确性和效率都大幅度降低。本文提出一种新的基于p2不变量的图象检索算法,该算法提取图象中关键点的位置(SIFT key location),计算该图象点集的p2不变量,并通过比较图象中p2不变量的值的方式来确定图象间的相似度。用3类图象库(战斗机、花朵、动物)实验的结果都验证了该算法具有较好的平移、尺度和旋转不变性。国家自然科学基金项目(60373080)部分资助;; 福建省自然科学基金项目(A0310009)资助;; 厦门大学985二期信息技术创新平台项目(2004-2007)资助;; 厦门大学院士启动基金项目资

    A preliminary study on the inexact man-model interactive environmental system program method For economic development zone

    No full text
    简要分析了经济开发区环境规划的特点,指出目前所采用的方法不可能有效地实现对开发区环境经济系统的优化设计。为了解决这个问题,文中提出一套基于环境承载力的不确定性人-模交互式环境系统规划方法,将大气、水及资源等子系统有机地通过模型整合起来,并充分考虑到了环境经济系统的不确定性与部分因子的不可量化性,通过人与模型的交互过程,将决策者及专家的知识和经验与模型结合起来,从而尽可能地保证规划决策结果的科学性和可操作性Based on some brieF analysis on the characteristic of the environmental planning For economic demelopment zone,this paper suggests that the presently applied program methods are unable to eFFectively opptimize the regional environ economic system.To solve this problem,the paper proposed a environmental support capacity based inexact man model interactive environmental system program method,which integrated the atmosperic environment,water environment and resources through a group of models,and give Full consideration to the uncertainty of the environ economic system.Through the interactive process between man and model,the experiences and knowledge of the decision makers and the experts are combined with the model,so as to guarantee the rationality and practicability of the planning decision.国家教委海洋生态环境开放研究实验室资助课

    黄鳝体内寄生隐藏新棘虫和胃瘤线虫的频率分布及季节动态

    No full text
    寄生虫的感染会对黄鳝(Monopterus albus Zuiew,1793)造成不利影响,其中寄生其肠道的隐藏新棘虫(Pallisentis(Neosentis) celatus van Cleave,1928)和寄生于体腔的胃瘤线虫幼虫(Eustrongylides sp.)对黄鳝健康的影响尤其严重,研究调查了以上两种寄生蠕虫在黄鳝体内的频率分布以及季节动态。在连续23个月内共调查黄鳝1980尾,结果显示,隐藏新棘虫的感染率为34.46%,平均丰度为2.94±8.37,平均丰度与鱼类体长之间呈显著正相关关系(R=0.16,P〈0.05),平均丰度和聚集度在42cm≤L〈48cm体长组达到最大值后开始下降,呈现凸形曲线。胃瘤线虫幼虫感染率为15.14%,平均丰度为0.61±2.45,平均丰度与鱼类体长之间呈显著负相关关系(R=-0.14,P〈0.05),平均丰度在24cm≤L〈30cm体长组达到最大值后开始逐渐下降,聚集度是在30cm≤L〈36cm体长组达到最大值后开始下降。各月份间隐藏新棘虫的平均丰度和感染率都有显著性差异(F=10.50,P〈0.05;G=84.44〉χ20.0522=33.9),感染主要发生在春季和秋季;胃瘤线虫幼虫各月份间的平均丰度和感染率也都有显著性差异(F=6.70,P〈0.05;G=143.88〉χ20.0522=33.9),感染主要发生在春末夏初
    corecore