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基于网络模型的等高线群拓扑关系表示

遥感学报 2007年第2期11卷 145-151页

作者：吴凡粟卫民武汉大学地图科学与地理信息工程系地理信息系统教育部重点实验室湖北武汉430079

等高线群拓扑关系的提取和表示是基于等高线的空间推理和地形特征挖掘的关键。在顾及地形特征的基础上,本文提出了一种拓扑关系网络来组织地理目标之间的拓扑关系,并进而提出分区二叉树、增量等高线树、等高线拓扑关系网三种拓扑关系网... 详细信息

等高线群拓扑关系的提取和表示是基于等高线的空间推理和地形特征挖掘的关键。在顾及地形特征的基础上,本文提出了一种拓扑关系网络来组织地理目标之间的拓扑关系,并进而提出分区二叉树、增量等高线树、等高线拓扑关系网三种拓扑关系网络来组织含未封闭等高线的复杂等高线群的拓扑关系,从而从根本上解决了等高线群的侧向不连续性,使基于等高线的空间推理更加简便和准确。

关键词：知识表示拓扑关系等高线群地貌网络模型

The Study and Applications of Sparse Methods Technology in Yunnan Mountain Substation

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Journal of Power and Energy Engineering 2014年第4期2卷 411-415页

作者： Hongliang Wang min Cao Xianfu Chen Shilin Li Shaoquan Zhang xin Shen Postdoctoral Research Workstation of YunNan Power Grid Corporation Kunming China Yunnan Electric Power Test & Research Institute Group Co. Ltd. Electric Power Research Institute Kunming China

As one of the divisions in China Southern Power Grid, Yunnan Power Grid Corporation has conducted research and demonstration projects on multiple smart grid technologies to improve the power system reliability, save operation cost and enhance measurement accuracy. In this paper, we will introduce The Study of Yunnan Mountain Substation Data Aggregation Technology based on Sparse Methods. Most substations are built in the mountain, the complex geological conditions and poor natural conditions put forward higher requirements on the substation running and real-time comprehensive monitoring of substation system. Processing and polymerization research of large amounts of the monitoring data and information is studied in this article. This paper introduces the sparse methods and then explains the thinning algorithm, especially new algorithm is proposed. Finally, the substation sparse method architecture is put forward and the simulation experiment was carried out to prove the feasibility and effectiveness of the proposed method.

关键词： Sparse Methods Mountain Substation Geological Monitoring Wireless Sensor Networks

Assembly of lamins in vitro

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Cell Research 1996年第1期6卷 11-22页

作者： min GUNG WEI XIANG JUN TONG BIN CHEN BOZHANG ZHONG fan LIU minG XIAO DING ZHONGHE ZHAI(College of Life Sciences, Peking UniversityCollege of Chemistry and Molecular Engineering, PekingUniversity Beijing 100871, China.) College of Life Sciences Peking University College of Chemistry and Molecular Engineering Peking University Beijing China

After lamins A, B and C were isolated and purified from rat liver, their assembly properties were examined by electron microscopy and scanning tunneling microscopy using negative staining and the glycerol coating method,respectively By varying the assembly time or the ionic conditions under which polymerization takes place, we have observed different stages of lamin assembly, which may provide clues on the structure of the 10 nm lamin filaments. At the first level of structural organization, two lamin polypeptides associate laterally into dimers with the two domains being parallel and in register. At the second level of structural organization, two dimers associate in a half-staggered and atiparallel fashion to form a tetramer 75 nm in length. At the third level of structural organization, 4-10 lamin tetramers associate laterally in register to form 75 nm long 10nm filaments, which in turn combine head to head into long, fully assembled lamin *** assembled lamin filaments are nonpolar.

关键词： Nuclear lamina lamins scanning tunneling microscopy assembly

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戊二酸二甲酯水解工艺的研究

中北大学学报（自然科学版） 2011年第5期32卷 600-605页

作者：李秀华范欣华南理工大学化学与化工学院广东广州510641

用001×7型阳离子交换树脂催化水解戊二酸二甲酯制取戊二酸,考查了反应温度、反应时间、水与戊二酸二甲酯的物质的量比、树脂浓度等工艺条件对戊二酸收率的影响,筛选出了戊二酸二甲酯水解反应制取戊二酸的最优条件:油浴温度为130℃,水... 详细信息

用001×7型阳离子交换树脂催化水解戊二酸二甲酯制取戊二酸,考查了反应温度、反应时间、水与戊二酸二甲酯的物质的量比、树脂浓度等工艺条件对戊二酸收率的影响,筛选出了戊二酸二甲酯水解反应制取戊二酸的最优条件:油浴温度为130℃,水与戊二酸二甲酯物质的量比12∶1,反应时间为2 h,催化剂浓度为170 g/L,戊二酸的收率为88.84%.重复试验结果证明:树脂性能稳定,可以重复多次使用.

关键词：戊二酸二甲酯戊二酸阳离子交换树脂催化水解

A New Approach to VC Routing in ATM Networks

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Wuhan University Journal of Natural Sciences 2000年第3期5卷 329-333页

作者： Li Sheng-hong Du xin-hua Zhu Hong-wen Liu Ze-min Department of Electronic Engineering Shanghai Jiaotong University Shanghai China Department of Radio Engineering Beijing University of Posts and Telecommunications Beijing China

A new ant-algorithm-based routing approach is proposed for the VC routing problem with considering the comprehensive effect between the resource utilization and the load balance in ATM networks. In the approach, the backup paths are calculated first, and then an ant algorithm based on the ability of ants to find the shortest path between their nest and the food source during their searching food, is constructed to optimize the VC global route. Simulation results show that the proposed approach can realize VC routing effectively according to the current traffic states in the networks and the user-specified delay requirements.

关键词： ATM networks virtual channel (VC) ant algorithm routing

学术权威人物个案研究的理念与方法论——美国教育技术学领军人物学术思想研究述评

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现代教育技术 2010年第1期20卷 5-9页

作者：桑新民南京大学教育科学与管理系网络化学习与管理研究所江苏南京210093

文章回顾、总结了"美国教育技术学领军人物学术思想研究"的初衷、价值和阶段性成果,反思和评价了该项系列研究的成功与不足之处,在对美国教育技术学历史与逻辑的把握中,梳理了美国教育技术作为一个领域产生发展的基本脉络,揭示了‘媒体... 详细信息

文章回顾、总结了"美国教育技术学领军人物学术思想研究"的初衷、价值和阶段性成果,反思和评价了该项系列研究的成功与不足之处,在对美国教育技术学历史与逻辑的把握中,梳理了美国教育技术作为一个领域产生发展的基本脉络,揭示了‘媒体派’和‘学习派’的双峰对峙与双重变奏是美国教育技术学发展的内在矛盾和内在动力。文章阐述了借鉴美国同行经验的三点启示,提出从学术领军人物成长土壤的研究和内在精神世界的探究两方面深化本项研究的思路,并强调开展个案研究要不断提高研究的层次和水平,由"追随"到"平等对话",能否取得与发达国家教育技术学同行进行"平等对话"的资格,取决于中国教育技术领域发展的实力和教育技术学科建设特别是基础理论研究和专业人才培养所达到的水平。

关键词：教育技术学领军人物个案研究方法论

Immunomodulating Activities of Polysaccharides from ZhuQin Formula and Atractylodes in Hypoimmune Mice

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Medicinal Plant 2018年第1期9卷 67-71页

作者： min PANG Yichen LUO Yongfeng HAO xin YUE Zhaorong ZHU Juan LIU College of Animal Science Southwest University Veterinary Science Engineering Research Center

[Objectives] To investigate the infrared identification of ZhuQin Formula and Atractylodes polysaccharides and its effect on immune function in immunocompromised mice. [Methods] In this experiment,the structure of polysaccharides was analyzed by Fourier transform infrared spectroscopy. The experiment was divided into the polysaccharide groups of high,medium and low dose of ZhuQin,the extraction group of ZhuQin,the polysaccharide group of Atractylodes,the positive drug group,the blank group and the model group. The model of immunosuppressed mice was established by intraperitoneal injection of cyclophosphamide. The carbon clearance index,immune organ index,serum hemolysin,spleen T and B lymphocyte transformation rate were determined. [Results]The results show that the polysaccharides have obvious absorption peaks of polysaccharides; Formula extracts and polysaccharides can enhance the immune function of immunosuppressive mice at a certain dose level,and the effect of formula polysaccharide is better than that of extract and single traditional Chinese medicine polysaccharides. [Conclusions] The results suggest that the polysaccharides of ZhuQin Formula and Atractylodes may be acidic polysaccharides containing pyran ring and furan ring. ZhuQin Formula polysaccharide may play an immunomodulatory role mainly by improving the specific immunity of the organism.

关键词： ZhuQin Formula polysaccharide Atractylodes polysaccharide Fourier transform infrared spectroscopy Immune function

耦合视角下长三角地区城镇化协调度的时空特征及交互机制

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地理研究 2020年第2期39卷 289-302页

作者：范擎宇杨山胡信南京师范大学地理科学学院南京210023 江苏省地理信息资源开发与利用协同创新中心南京210023

随着中国城镇化发展的转型,测度城镇化过程中人口、土地和经济三者发展的耦合协调关系,探索其演化过程的时空动态规律,已成为人文地理学研究新型城镇化的重要科学问题。通过构建耦合协调度模型,在测度近16年来长三角地区城镇化进程中各... 详细信息

随着中国城镇化发展的转型,测度城镇化过程中人口、土地和经济三者发展的耦合协调关系,探索其演化过程的时空动态规律,已成为人文地理学研究新型城镇化的重要科学问题。通过构建耦合协调度模型,在测度近16年来长三角地区城镇化进程中各子系统的协调发展水平的基础上,运用空间变差函数,LISA时空跃迁等方法,分析长三角地区城镇化耦合协调的交互过程,探索其城镇化协调空间集聚的形成机制。结果表明:①伴随长三角地区城镇化水平的显著提升,"人口、土地和经济"总体和两两耦合协调度演化均呈稳步提升的趋同现象;②长三角地区城镇化耦合协调度空间集聚程度逐年增强,空间关联作用范围不断扩大,形成了"一极独大、三角核心、周边低平"的空间形态;③从各个城市的城镇化耦合水平跃迁路径来看,大多呈协同增长态势,表明城市的整体耦合协调度具有明显的路径依赖和空间锁定特征;④长三角地区城镇化耦合协调水平从稳定和均衡→极化集聚状态的演变动力主要来自于土地-经济的交互作用,而从极化→均衡状态的演变动力更多地来自于人口-土地的交互作用。城镇化协调度的交互过程及机制研究为新型城镇化发展和长三角城市群构建提供了理论依据和调控方向。

关键词：城镇化耦合协调度 LISA时间路径长三角地区

改进型逆有限元法在某轿车翼子板快速成形模拟中的应用

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塑性工程学报 2006年第1期13卷 1-4页

作者：闫亚坤庄蔚敏那景新吉林大学机械科学与工程学院长春1300223 吉林大学汽车工程学院长春130022

为提高一步成形逆有限元法的模拟精度,将四节点等参膜单元应用于一步成形计算,并对空间四边形单元的四个节点可能不在同一平面引起的单元翘曲进行了修正,编写了计算机程序,对某轿车翼子板进行了实际模拟,通过一步模拟结果与增量法模拟... 详细信息

为提高一步成形逆有限元法的模拟精度,将四节点等参膜单元应用于一步成形计算,并对空间四边形单元的四个节点可能不在同一平面引起的单元翘曲进行了修正,编写了计算机程序,对某轿车翼子板进行了实际模拟,通过一步模拟结果与增量法模拟结果和实验结果的对比,发现改进后的一步成形模拟结果与增量模拟结果已非常接近,而计算时间不到增量法的1/30,进而验证了本文方法的有效性。

关键词：一步成形逆有限元法等参膜单元翘曲修正