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Study of MA Protection technology of Extending Inheritance Hierarchy Trees in IDC Network Management

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Study of MA Protection Technology of Extending Inheritance H...

2009中国控制与决策会议

作者： Wu Jiehong~1,Liu Cheng~1,Gao Fuxiang~2 1.Engineering Training center,shenyang institute of Aeronautical and Engineering,shenyang 110136,china 2.College of Information Science and Engineering,Northeastern University,shenyang 110006,china

Mobile agents(MA) are autonomous software entities that are able to migrate across heterogeneous network execution *** and autonomy compensate the deficiencies of distributed technology pretty well. Thus,mobile agents have wide application *** the security issues with mobile agents have not been solved and are becoming obstacles for the application of mobile *** with host protection,the research on mobile agent protection is still at the beginning *** is a technique in which the mobile code producer enforces the security policy by applying a behavior transformation to the code before sending it to run on different *** paper presents a protection scheme of mobile agent in network management application,which combining method of extending inheritance hierarchy tree and time checking technology to protect the security of *** protection scheme is tested in actual network management environment,which can effectively identify the malicious host.

关键词： mobile agent extending inheritance hierarchy tree active protection time checking

Safety Protection Control for a Class of Linear Systems via Switching Strategy

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Safety Protection Control for a Class of Linear Systems via ...

第三十届中国控制会议

作者： CHEN Chao~1,YU Daren~2,BAO Wen~2,ZHAO Jun~1 1.State Key Laboratory of Integrated Automation for Process Industries,Northeastern University, shenyang 110819,P.R.china 2.Harbin institute of technology,Hypersonic technology research center,Harbin 150001,P.R.china

＜正＞For a class of linear systems,which can be considered as the simplified hypersonic air-breathing propulsion model,focusing on the safe boundaries existing during the working progressing,this paper studies the output regulation/ safety protection switching control *** remarks are given to the switching control based on minimum switching law studied in our previous work,and to make the designing of the switching controller more systematic,a novel reference command switching strategy is proposed,where a discontinuous controller is adapted,and the asymptotic tracking problem is transformed into the asymptotic stability problem of the linear switched and impulsive *** stability of the switching control system is illustrated,and the principle guaranteeing asymptotic tracking is ***,impacts of switching condition and size of jumping step on the response performances are studied through simulation and it is pointed out that reference commands switching can improve both overshooting and setting time,the ability of tracking commands safely and quickly is *** addition,the design of PI controller and the switching law can be completed separately, and the switching control law is utility.

关键词： Hypersonic Air-Breathing Propulsion Safety Protection Command Switching Control Discontinuous Controller Tracking Linear Switched and Impulsive System

Study on Algorithm for Interference-free Tool path Generation of Free-form Surfaces Based on Z-map Model

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Study on Algorithm for Interference-free Tool path Generatio...

2009 9th International Conference on Electronic Measurement & Instruments（ICEMI’2009）

作者： Zhixiang Shao 1 2 Ruifeng Guo 2 Jie Li 1 2 Jianjun Peng 1 2 1 Graduate University of Chinese Academy of Science Beijing 100039 china 2 shenyang institute of Computing technology Chinese Academy of Science shenyang 110171 Liaoning china

Tool path generation is an important research content in NC machining of free-form surfaces. In this paper, according to analyzing tool path generation strategies and algorithms, a new tool path generation algorithm based on Z-map model is designed and implemented. The triangulation approach is employed to acquire higher machining precision, Multi-Objective evolutionary algorithm is used to detect tool interference, which not only avoids the gouge problems resulting from unsuitable forward step during tool movement, but also ensures the generated tool path is interference-free tool path.

关键词： NC machining tool-path generation Z-map triangulation evolutionary algorithm

环氧树脂高温热老化反应对器件功率循环寿命的影响机理

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半导体技术 2024年第9期49卷 858-866,872页

作者：王作艺严雨行邓二平莫申扬吴立信吴天华黄永章新能源电力系统全国重点实验室(华北电力大学) 北京102206 合肥工业大学电能高效高质转化全国重点实验室合肥230009 合肥综合性国家科学中心能源研究院合肥230051 南瑞集团(国网电力科学研究院)有限公司南京211106

分立器件主要使用环氧树脂封装材料以保护芯片免受机械损伤和环境腐蚀,但环氧树脂材料的热稳定性较差,在高温环境下易发生化学反应,影响器件的性能。因此,一般要求器件的工作温度不能超过环氧树脂的玻璃化转变温度。以SiCMOSFET分立器... 详细信息

分立器件主要使用环氧树脂封装材料以保护芯片免受机械损伤和环境腐蚀,但环氧树脂材料的热稳定性较差,在高温环境下易发生化学反应,影响器件的性能。因此,一般要求器件的工作温度不能超过环氧树脂的玻璃化转变温度。以SiCMOSFET分立器件为研究对象,通过功率循环试验深入探究高温存储对器件功率循环寿命的影响。结果表明,经高温存储后器件的寿命得到显著提升。此外,通过对高温存储前后环氧树脂材料进行热机械分析,发现环氧树脂材料的热稳定性经高温存储后得到增强。最后,通过建立有限元仿真模型,深入分析高温存储对器件芯片表面应变及键合线应变的影响,发现高温存储后器件芯片表面应变及键合线应变变小,解释了高温存储对器件寿命提升的影响机理。

关键词：功率循环寿命 SiCMOSFET分立器件环氧树脂高温存储玻璃化转变温度

Genetic relationship between parasitized and non-parasitized Haloxylon ammodendron in the Alxa Desert

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Journal of Systematics and Evolution 2009年第3期47卷 255-262页

作者： 1,2,3Xu-Mei WANG 1Dong-Ye YANG 4Yong-Zhen TIAN 5Peng-Fei TU 2Qi-Shi SUN 1Xiao-Bo LI 1(School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, china) 2(College of Traditional Chinese Materia Medica, shenyang Pharmaceutical University, shenyang 110016, china) 3(School of Medicine, Xi’an Jiaotong University, Xi’an 710061, china) 4(Forest and Desert Control research institute of Alxa League, Alxa League 750306, china) 5(Modern research center of Traditional Chinese Medicine, School of Pharmaceutical Sciences, Peking University, Beijing 100083, china) (Modern research center of Traditional Chinese Medicine School of Pharmaceutical Sciences Peking University Beijing 100083 China)

Haloxylon ammodendron (C. A. Mey.) Bunge is a host for the holoparasitic plant Cistanche deserticola Y. C. Ma, the original source of medicinal material known as Herba Cistanchis. The inter-simple sequence repeat marker was used to assess the genetic variations and relationships among six accessions of H. ammodendron with a total of 120 individuals collected from three localities in the Alxa Desert, Inner Mongolia, china. At each locality, individuals both parasitized (PP) by C. deserticola and non-parasitized (NP) were sampled. The results showed that Nei’s gene diversity and Shannon’s index of PP accessions were higher, but were not significantly different, from those of NP accessions. An unweighted pair-group method arithmetic average dendrogram showed two clusters, one that included all PP accessions, and the other the NP accessions. Genetic differentiation therefore existed between PP and NP accessions, which might be attributed to low gene flow between the NP and PP groups (Nm<1). However, the relationship between genetic distance and geographic distance within each group, although not statistically significant in this study, might be associated with high gene flow in both the NP and PP groups.

关键词： genetic relationship Haloxylon ammodendron ISSR marker parasitism.

Graph-Based Model of Cast Planning Problem and Its Optimization

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Graph-Based Model of Cast Planning Problem and Its Optimizat...

2011 Chinese Control and Decision Conference（CCDC）

作者： Ruiyou Zhang and Dingwei Wang are with College of Information Science and Engineering,Key Laboratory of Integrated Automation of Process Industry,Ministry of Education,Northeastern University,shenyang 110819,china Kebin Lu,Kewei Huang,are with institute of Automation,Baosteel technology center,Shanghai 201900,china

This paper investigates a type of cast planning problem arising in real-life engineering *** problem is mathematically modeled based on a directed *** number of casts is unknown in advance whereas all the charges should be *** problem falls into an extension of the traditional multiple traveling salesman problem （m-TSP）.In the extended m-TSP,there are multiple city types,one salesman can visit only one type of cities,and the distances between cities are *** objective of the problem is to minimize both the total distance and the number of salesman *** improved genetic algorithm is developed to solve the problem and validated by using numerical *** results indicate that the algorithm is relatively fast,stable,and effective.

关键词： steelmaking and continuous casting cast planning problem multiple traveling salesman problem graph genetic algorithm

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流体润滑动态观测试验机的研制

沈阳工业学院学报 1998年第4期17卷 7-12页

作者：张志军丛刚史亦农唐日福沈阳工业学院机械工程系辽展时装股份有限公司沈阳工业学院

流体润滑动态观测试验机适用于流体润滑中动力油膜、化学油膜形成的动态观测．载荷、速度和温度可在较大范围内进行调整．各物理量的测定均采用计算机进行．

关键词：流体润滑动态观测试验机润滑

Advances in Studies on Chemistry,Pharmacological Effect,and Pharmacokinetics of Eurycoma longifolia

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Chinese Herbal Medicines 2011年第3期3卷 186-195页

作者： HOU Wen-bin1,2,3,XIAO Xue-feng1,GUO Wei4,ZHANG Tie-jun2,3 1.Tianjin University of Traditional Chinese Medicine,Tianjin 300193,china 2.research center for Modern Chinese Materia Medica,Tianjin institute of Pharmaceutical research,Tianjin 300193,china 3.State Key Laboratory of Drug Delivery technology and Pharmacokinetics,Tianjin institute of Pharmaceutical research,Tianjin 300193,china 4.Xiehe Pharmaceutical Group Company,shenyang 110179,china Tianjin University of Traditional Chinese Medicine Tianjin 300193China research center for Modern Chinese Materia Medica Tianjin Institute of Pharmaceutical ResearchTianjin 300193China State Key Laboratory of Drug Delivery technology and Pharmacokineti Tianjin University of Traditional Chinese Medicine Tianjin 300193China Xiehe Pharmaceutical Group Company Shenyang 110179China research center for Modern Chinese Materia Medica Tianjin Institute of Pharmaceutical ResearchTianjin 300193China State Key Laboratory of Drug Delivery technology and Pharmacokinetics Tianjin Institute of Pharmaceutical ResearchTianjin 300193China

Eurycoma longifolia,also known as Tongkat Ali in Malaysia,as one of traditional herbal medicines,is used for centuries in South-East *** the discovery of anticancer and anti-HIV properties,this herbal medicine has attracted great attention *** this review,the following information on ***,including chemistry,bioactivities,pharmacokinetics,clinical studies,and side effects and safety,was *** results,to a certain extent,will provide scientific base for commercial utilization and clearance of the Tongkat Ali products with regard to consumers’ safety.

关键词： chemistry clinical study Eurycoma longifolia pharmacokinetics pharmacological effects

块状LaNi_5基纳米合金的正电子湮灭研究

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中国稀土学报 2003年第3期21卷 299-302页

作者：隋郁熊良钺龙期威苏文辉哈尔滨工业大学理学院应用物理系凝聚态科学与技术研究中心黑龙江哈尔滨150001 中国科学院国际材料物理中心

利用高温高压技术,在不同的压力和温度(～4.5GPa,～800℃)下将LaNi5基快淬合金粉直接压制成了块状纳米晶合金。X射线衍射分析表明,高压使其晶粒内部发生了明显的压致晶粒碎化,其平均晶粒尺寸在4.5GPa下从75.5nm降至24.6nm。利用正电子... 详细信息

利用高温高压技术,在不同的压力和温度(～4.5GPa,～800℃)下将LaNi5基快淬合金粉直接压制成了块状纳米晶合金。X射线衍射分析表明,高压使其晶粒内部发生了明显的压致晶粒碎化,其平均晶粒尺寸在4.5GPa下从75.5nm降至24.6nm。利用正电子湮灭技术研究了这种晶粒碎化效应对纳米合金内部缺陷结构的影响。测试结果表明,在高温高压的作用下,由于界面上原子的迁移和弛豫加剧,导致晶界上尺寸较大的微孔隙缺陷逐渐转化为尺寸较小的自由体积缺陷,使得纳米合金的致密度逐渐增强,显微硬度逐渐升高,从而在高温高压下得到致密的块状纳米合金材料。

关键词：凝聚态物理学压致碎化 LaNi5基合金纳米固体正电子湮灭稀土