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CAD Model-Based Intelligent Inspection Planning for Coordinate Measuring Machines

Chinese Journal of Mechanical Engineering 2011年第4期24卷 567-583页

作者： DONG Yude liu daxin ZHAO Han WANG Wanlong WU Juan School of Mechanical ＆ Automotive Engineering Hefei University of Technology Hefei 230009 China Hefei Winster Technology Ltd. Hefei 230088 China

As the market competition among enterprises grows intensively and the demand for high quality products increases rapidly, product quality inspection and control has become one of the most important issues of manufacturing, and improving the efficiency and accuracy of inspection is also one of problems which enterprises must solve. It is particularly important to establish rational inspection planning for parts before inspecting product quality correctly. The traditional inspection methods have been difficult to satisfy the requirements on the speed and accuracy of modern manufacturing, so CAD-based computer-aided inspection planning （CAIP） system with the coordinate measuring machines （CMM） came into being. In this paper, an algorithm for adaptive sampling and collision-free inspection path generation is proposed, aiming at the CAD model-based inspection planning for coordinate measuring machines （CMM）. Firstly, using the method of step adaptive subdivision and iteration , the sampling points for the specified number with even distribution will be generated automatically. Then, it generates the initial path by planning the inspection sequence of measurement points according to the values of each point＇s weight sum of parameters, and detects collision by constructing section lines between the probe swept-volume surfaces and the part surfaces, with axis-aligned bounding box （AABB） filtering to improve the detection efficiency. For collided path segments, it implements collision avoidance firstly aiming at the possible outer-circle features, and then at other collisions, for which the obstacle-avoiding movements are planned with the heuristic rules, and combined with a designed expanded AABB to set the obstacle-avoiding points. The computer experimental results show that the presented algorithm can plan sampling points＇ locations with strong adaptability for different complexity of general surfaces, and generate efficient optimum path in a short time and avoid collisio

关键词： coordinate measuring machines (CMM) sampling strategy adaptive subdivision path planning collision detection collision avoidance bounding box

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WEB BASED TRANSLATION OF CHINESE ORGANIZATION NAME

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Journal of Electronics(China) 2009年第2期26卷 279-284页

作者： Yang Muyun liu daxin Zhao Tiejun Qi Haoliang Lin Kaiming School of Computer Science and Technology Harbin Engineering University Harbin 150001 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China Department of Computer Heilongjiang Institute of Technology Harbin 150080 China

A web-based translation method for Chinese organization name is *** ana-lyzing the structure of Chinese organization name,the methods of bilingual query formulation and maximum entropy based translation re-ranking are suggested to retrieve the English translation from the web via public search *** experiments on Chinese university names demonstrate the validness of this approach.

关键词： Named entity Chinese organization name translation Bilingual query Web search

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强制访问控制在基于角色的保护系统中的实现

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计算机工程 2006年第6期32卷 167-169页

作者：崔宾阁刘大昕哈尔滨工程大学计算机科学与技术学院哈尔滨150001

研究了通过对基于角色的访问控制(RBAC)进行定制实现强制访问控制(MAC)机制的方法。介绍了RBAC模型和MAC模型的基本概念,讨论了它们之间的相似性,给出了在不考虑角色上下文和考虑角色上下文两种情形下满足强制访问控制要求的RBAC系统的... 详细信息

研究了通过对基于角色的访问控制(RBAC)进行定制实现强制访问控制(MAC)机制的方法。介绍了RBAC模型和MAC模型的基本概念,讨论了它们之间的相似性,给出了在不考虑角色上下文和考虑角色上下文两种情形下满足强制访问控制要求的RBAC系统的构造方法。从这两个构造中可以看出,强制访问控制只是基于角色的访问控制的一种特例,用户可以通过对RBAC系统进行定制实现一个多级安全系统。

关键词：基于角色的访问控制强制访问控制基于格的访问控制

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基于实体语义的多级安全数据模型

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计算机工程 2006年第8期32卷 157-158,212页

作者：崔宾阁刘大昕哈尔滨工程大学计算机科学与技术学院哈尔滨150001

提出了一种基于实体语义的多级安全数据模型。该模型借鉴了Smith-Winslett模型基于置信的语义和MLR模型数据借用的思想。定义了ESM数据模型,并描述了它的4个完整性性质和4个数据操作。ESM模型消除了语义模糊性,同时又保持了向上的信息... 详细信息

提出了一种基于实体语义的多级安全数据模型。该模型借鉴了Smith-Winslett模型基于置信的语义和MLR模型数据借用的思想。定义了ESM数据模型,并描述了它的4个完整性性质和4个数据操作。ESM模型消除了语义模糊性,同时又保持了向上的信息流。证明了ESM模型的正确性、完备性和安全性。

关键词：多级安全实体语义语义模糊性

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多处理器单调速率任务分配算法性能评价

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计算机科学 2007年第1期34卷 272-277页

作者：王涛刘大昕哈尔滨工程大学计算机科学与技术学院哈尔滨150001

多处理器任务分配调度算法是一类经典实时调度算法,然而目前研究在如何根据任务集特征选择任务分配算法方面少见指导性原则,不利于提高多处理器任务分配算法的可调度率及使用尽可能少的处理器达到最优调度结果。基于两种多处理器任务调... 详细信息

多处理器任务分配调度算法是一类经典实时调度算法,然而目前研究在如何根据任务集特征选择任务分配算法方面少见指导性原则,不利于提高多处理器任务分配算法的可调度率及使用尽可能少的处理器达到最优调度结果。基于两种多处理器任务调度策略的比较,本文给出划分策略下的多处理器RM调度的可调度条件和任务分配算法及分析。仿真结果表明,各任务分配算法所需处理器数与任务集总利用率成正比。同时,分析总结出各算法适用范围及如何根据任务集利用率选择合适算法的指导原则。最后结果还表明,实际算法性能与理论性能界存在差异。

关键词：多处理器速率单调划分可调度性

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Comprehensive Marine Observing Experiment Based on High-Altitude Large Unmanned Aerial Vehicle(South China Sea Experiment2020 of the “Petrel Project”)

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Advances in Atmospheric Sciences 2021年第4期38卷 531-537页

作者： Xuefen ZHANG Liangxu LI Rongkang YANG Ran GUO Xia SUN Jianping LUO Hongbin CHEN daxin liu Kebing TANG Wenwu PENG Xiaodong HAN Qiyun GUO Xiaoxia LI Xikun FEI Meteorological Observation Center of the China Meteorological Administration Beijing 10081China AVIC Chengdou Aircraft Industry(Group)Co. Ltd.Chengdou 610092China Hainan Provincial Meteorological Bureau of the China Meteorological Administration Hainan 570203China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Beijing Institute of Radio Measurement China Aerospace Science and IndustryCorporationBeijing 100854China AVIC Leihua Electric Technology Research Institute Wuxi 421063China

In collaboration with 12 other institutions, the Meteorological Observation Center of the China Meteorological Administration undertook a comprehensive marine observation experiment in the South China Sea using the Yilong-10 high-altitude large unmanned aerial vehicle(UAV). The Yilong-10 UAV carried a self-developed dropsonde system and a millimeter-wave cloud radar system. In addition, a solar-powered unmanned surface vessel and two drifting buoys were used. The experiment was further supported by an intelligent, reciprocating horizontal drifting radiosonde system that was deployed from the Sansha Meteorological Observing Station, with the intent of producing a stereoscopic observation over the South China Sea. Comprehensive three-dimensional observations were collected using the system from 31 July to2 August, 2020. This information was used to investigate the formation and development processes of Typhoon Sinlaku(2020). The data contain measurements of 21 oceanic and meteorological parameters acquired by the five devices, along with video footage from the UAV. The data proved very helpful in determining the actual location and intensity of Typhoon Sinlaku(2020). The experiment demonstrates the feasibility of using a high-altitude, large UAV to fill in the gaps between operational meteorological observations of marine areas and typhoons near China, and marks a milestone for the use of such data for analyzing the structure and impact of a typhoon in the South China Sea. It also demonstrates the potential for establishing operational UAV meteorological observing systems in the future, and the assimilation of such data into numerical weather prediction models.

关键词： high-altitude large UAV marine typhoon unmanned surface vessel horizontal drifting radiosonde drifting buoy

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常数级压缩方法的优化

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江苏大学学报（自然科学版） 2010年第1期31卷 78-81页

作者：陆军刘大昕黑龙江大学计算机科学与技术学院黑龙江哈尔滨150080 哈尔滨工程大学计算机科学与技术学院黑龙江哈尔滨150001

为提高常数级压缩方法效率,对核心算法所需时间和频率表空间进行了优化.首先对基数计算进行优化,推导出相关优化公式;其次用20组球进行试验,对不同基数计算方法进行了对比;最后对频率表空间进行优化.结果表明,比例运算可有效提高基数计... 详细信息

为提高常数级压缩方法效率,对核心算法所需时间和频率表空间进行了优化.首先对基数计算进行优化,推导出相关优化公式;其次用20组球进行试验,对不同基数计算方法进行了对比;最后对频率表空间进行优化.结果表明,比例运算可有效提高基数计算速度;在内容随机分段中,越靠近字节平均频率值的位置字节频率出现的次数越多;根据这一特征对频率表空间进行优化,所做的优化节省了存储空间,从而提高了压缩率.这些优化策略推动了常数级压缩算法的实用化.

关键词：数据压缩编码频率统计样品

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Intervention of rosiglitazone on myocardium Glut-4 mRNA during ischemia-reperfusion injury in cardio-pulmonary bypass in dogs

Intervention of rosiglitazone on myocardium Glut-4 mRNA duri...

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2012贵州省医学会胸心血管外科年会

作者： Guiyou Liang Bin liu Gang Xu daxin liu Qingyong Cai Zhenyu Gao Thoracic and Cardiovascular Surgery Thoracic and Cardiovascular Surgery of Affiliated Hospital of Zunyi Medical College Surgical lab Zunyi Medical College

Myocardial ischemia-reperfusion(I/R) induces heart glucose metabolism *** previous research showed that the decreased glucose utilization is due to decreased Glut-4 expression and translocation to myocyte surface *** study further examined whether rosiglitazone,a synthetic agonist of peroxisome proliferator-activated receptor y,could intervene glucose metabolism by regulating Glut-4 mRNA during I/R in *** insulin and glucose concentrations were measured at pre-bypass(control),aortic cross-clamp off(I/R) at 15,45 and 75 *** left ventricle biopsies were taken for the expressions of Glut-4 mRNA by real-time *** dogs receiving 120-min ischemia,coronary arterial,venous glucose concentrations,plasma insulin levels and insulin resistant index(IRI) were increased,but the expression of Glut-4 mRNA was significantly decreased at 15 and 45 min of reperfusion,and remained low at 75 min of *** the other hand,these changes were relatively mild in dogs treated with rosiglitazone in cardioplegic solution and expression of Glut-4 mRNA was increased 20%.It is concluded that the decrease in total amount of Glut-4 mRNA expression could be one of the important molecular mechanisms which causes the myocardium insulin *** longer the ischemia lasts;the decrease in amount of Glut-4 was more *** rosiglitazone into the cardioplegic solution during I/R can increase the amount of Glut-4 mRNA expression,mitigate the myocardium insulin resistance and improve the myocardium I/R injury.

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Application of New Type of Detection Data in a Heavy Rainfall Process in Changsha

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Meteorological and Environmental Research 2019年第4期10卷 37-38,41页

作者： Huo Tao Shan Nan Tang Xiaonan Fan Yu liu daxin Changsha Meteorological Bureau Changsha 410205 China Changsha Comprehensive Meteorological Observation and Experiment Base of CMA Changsha 410205 China Weather Modification Office in Liaoning Province Shenyang 110016 China Meteorological Observation Center of CMA Beijing 100081 China

Using detection data with high space-time resolution from the wind profile radar and millimeter wave cloud radar of Changsha station, and combining observation data of ground automatic station, heavy precipitation process in Changsha area from June 29 to July 1, 2017 was analyzed. The results showed that the atmospheric temperature advection was calculated by inversion of wind profile radar data of boundary layer, and it could intuitively analyze changes of atmospheric temperature advection before and after precipitation process. The variation characteristics of intensity, thickness and height of warm and cold advection in the upper and lower levels were highly related to the evolution of the precipitation process. The millimeter wave cloud radar can better reflect the vertical structure and evolution of the cloud over the observatory, and had certain indications for the structure characteristics of cloud before the starting of precipitation. When the strong reflectivity started to approach the ground, it also meant that heavy precipitation began to appear.

关键词： Wind profile radar Millimeter wave cloud radar Temperature advection

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基于网页模糊分类的用户兴趣度分析方法

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计算机工程与应用 2005年第15期41卷 188-190页

作者：战立强刘大昕东北林业大学经济管理学院哈尔滨150040

了解用户的兴趣是电子商务网站实现个性化的基础,该文提出了一种分析用户兴趣度的新方法,该方法首先根据网站主索引页上的超链接将网站上的网页模糊分类,并通过对Web日志的统计,得出各交叉页的模糊度,然后综合考虑用户浏览网页的时间长... 详细信息

了解用户的兴趣是电子商务网站实现个性化的基础,该文提出了一种分析用户兴趣度的新方法,该方法首先根据网站主索引页上的超链接将网站上的网页模糊分类,并通过对Web日志的统计,得出各交叉页的模糊度,然后综合考虑用户浏览网页的时间长度、点击网页的次数,利用模糊综合评判得出用户对于各网页分类的兴趣度,再与各网页分类的平均兴趣度水平作对比,从而发现用户的兴趣所在,实验表明该方法是有效的。

关键词： Web日志交叉页模糊综合评判兴趣度

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