检索结果-南通市图书馆

Research on Electromagnetic Wave Absorption Based on Electrospinning Technology

2.07 8th International Conference on Electronic Measurement & Instruments（ICEMI’2.07）

作者： Liu Yunpeng 1 2.Wang Juan 1 Lv Fangcheng 1 Jiang Qingyun 3 (1. North China Electric Power University baoding 071003 China) (2. Wuhan High Voltage Research Institute of SGCC Hongshan District Wuhan 430074 China) (3. Xiamen Extrahigh Voltage Company Xiamen 361012.China)

An on-line monitoring system of ultra-high-frequency （UHF） PD was investigated for transformers in this paper. Based on envelope detection technique, the measure principle of UHF PD signals was analyzed, and the hardware of this system was developed. The software of this system, consisting of data acquisition data storage signal display and graph analysis, was constructed using National Instruments’ Measurement Studio software. The PD of five discharge models was measured. Experimental results show that this system has wider band width, stronger ability of interference suppression, and higher stability, and can be useful for on-line monitoring of UHF PD in transformers.

关键词： transformer partial discharge(PD) ultra-high-frequency(UHF) on-line monitoring Virtual Instrument

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第7期42卷 777-789页

作者： baoding Li Jing Qiao Yue Liu Haoyuan Tian Wei Liu Qilei Wu Zhou Wang Jiurong Liu Zhihui Zeng Key Laboratoryfor Liquid-Solid StructuralEvolution and Processing of Materials Schoolof Materials Science and EngineeringShandong UniversityJinanShandong 250061China China North Industries Group 53rd Research Institute JinanShandong 250000China School of Mechanical Engineering Shandong UniversityJinanShandong 250061China Institute of Crystal Materials State Key Laboratory of Crystal MaterialsShandong UniversityJinanShandong 250100China Shenzhen Research Institute of Shandong University ShenzhenGuangdong 518057China Science and Technology on Electromagnetic Compatibility Laboratory China Ship Development and Design CentreWuhanHubei 430064China suzhou Research Institute of Shandong University SuzhouJiangsu215123China

At present,in order to overcome electromagnetic interference and prevent electromagnetic harm,the research of new and efficient electromagnetic wave absorbing materials has become the research focus in the field of materials *** one-dimensional structure can promote the impedance matching and attenuation characteristics of the absorbing ***,as an effective method to prepare nanofibers with high length-diameter ratio,has been widely concerned because it is suitable for struc-tural design of various *** this paper,the research progress and absorption properties of nano-fiber materials prepared by electrospinning combined with different processes are introduced.

关键词： Electromagnetic wave(EMW)absorbing Electrospinning Nanofiber Impedance matching Nanocomposite

Automorphisms with order three of affine Lie algebras

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第21期43卷 1793-1798页

作者： JIN Quanqin 1,2.and HOU Zixin 2.1. Department of Mathematics, Hebei University, baoding 071002. China 2. Department of Mathematics, Nankai University, Tianjin 300071, China Department of Mathematics Hebei University Baoding China Department of Mathematics Nankai University Tianjin China

Some properties of automorphisms of affine Lie algebras are presented. Automorphisms with order three are classified up to conjugacy, and their fixed point sets are also computed. As a corollary, it is proved that two... 详细信息

关键词： affine Lie algebra automorphism of order three first (second) kind of automorphism.

Minimal symmetric submanifolds in compact Riemannian symmetric spaces

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第21期43卷 1786-1789页

作者： LIANG Ke 1 and JIN Quanqin 1,2.1. Department of Mathematics, Nankai University, Tianjin 300071, China 2. Department of Mathematics, Hebei University, baoding 071002. China Department of Mathematics Nankai University Tianjin China Department of Mathematics Hebei University Baoding China

A necessary and sufficient condition for a symmetric submanifold to be minimal in its ambient compact Riemannian symmetric space is given. By this condition a complete classification of non- minimal symmetric submanif... 详细信息

关键词： symmetric space symmetric submanifold mean curvature vector.

Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2. HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. College of Chemistry and Environment Science, Hebei University, baoding 071002. China 2. International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, China 3. College of Physics Science and Technology, Hebei University, baoding 071002. China 1. College of Chemistry and Environment Science Hebei University Baoding 071002 China 2. International Center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China 3. College of Physics Science and Technology Hebei University Baoding 071002 China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

Human hepatopoietin augmenter of liver regeneration──A hepatotrophic factor for liver regeneration, and its potential antihepatitis effect in vivo

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第12期43卷 1026-1031页

作者： YANG Xiaoming 1, WANG Aimin 2. ZHOU Ping 3, XIE Ling 1, WANG Qingming 1, WU Zuze 1 and HE Fuchu 1 1. Institute of Radiation Medicine, Beijing 100850, China 2. No. 2.2.Hospital of PLA, baoding 071000, China 3. General Hospital of the Air Institute of Radiation Medicine Beijing China No. 2.2.Hospital of PLA Baoding China General Hospital of the Air Force of PLA Beijing China

The effect of human hapatopoietin i.e. augmenter of liver regeneration (hALR) was determined on hepatocyte DNA synthesis, and on CCl 4-induced hepatitis in animal in vitro and in vivo. It is found that ALR could directly stimulate DNA synthesis of hepatocytes in primary culture in a dose-dependent manner. In 30% hepatectomied rats, significant DNA synthesis occurred in control rats ; even so, exogenous hALR gene encoding protein increased DNA synthesis of regeneration liver by 2.3 fold compared with control rats. A lower dose of CCl 4 was administrated in rats and the effect of ALR on DNA synthesis of regenerating liver 48 h after CCl 4 administration was analyzed. Few Budr-labeled hepatocytes were visible in control rats. However, exogenous hALR markedly increased the number of labeled cells in a dose-dependent manner. Statistical analysis showed that 10 or 40 μg·kg -1 ALR protein stimulated DNA synthesis by 1.7 and 4.8 fold respectively. In addition to enhancing cell growth, adiministration of hALR achieved a significant improvement in reversing the lethality of rat hepatic failure when compared with that of control group; the elevation of cytosolic enzymes was dramatically suppressed by exogenous hALR in CCl 4-treated mice in vivo and in vitro; histologically, hepatocytes around the central vein were necrotic, and the degree of hepatocyte necrosis in control mice was more prominent than that in the mice given 40 μg·kg-1 hALR 48 h after CCl 4 administration. We also noted that hALR had a strong antihepatitis effect in vitro which was determined with primary cultured rat hepatocytes. These findings suggest that hALR protects the integrity of hepatocytes against severe hepatitis, and indicate that ALR may be an important regulator of liver regeneration and play a major role in liver injury repair. It proves ALR adminstration to be a useful treatment to accelerate liver regeneration and to prevent the onset of hepatitis or intrahepatic cholestasis induced by toxin.

关键词： liver regeneration hepatopoietin DNA synthesis hepatitis.

基于贝叶斯网络强化学习的复杂装备维修排故策略生成

在线全文

学校读者我要写书评

暂无评论

北京航空航天大学学报 2024年第4期50卷 1354-1364页

作者：刘宝鼎于劲松韩丹阳唐荻音李鑫北京航空航天大学自动化科学与电气工程学院北京100191 北京航空航天大学仪器科学与光电工程学院北京100191 中国运载火箭技术研究院北京100076

为解决传统启发式维修排故决策方法决策时间长、生成策略总成本高的问题,提出一种基于贝叶斯网络(BN)结合强化学习(RL)进行复杂装备维修排故策略生成方法。为更好地利用复杂装备模型知识,使用BN进行维修排故知识表述,并且为更加贴近复... 详细信息

为解决传统启发式维修排故决策方法决策时间长、生成策略总成本高的问题,提出一种基于贝叶斯网络(BN)结合强化学习(RL)进行复杂装备维修排故策略生成方法。为更好地利用复杂装备模型知识,使用BN进行维修排故知识表述,并且为更加贴近复杂装备实际情况,依据故障模式、影响和危害性分析(FMECA)的故障概率,经合理转化后作为BN的先验概率;为使用RL的决策过程生成维修排故策略,提出一种维修排故决策问题转化为RL问题的方法;为更好地求解转化得到的强化学习问题,引入观测-修复动作对(O-A)以减小问题规模,并设置动作掩码处理动态动作空间。仿真结果表明:在统一的性能指标下,所提BN-RL方法较传统方法获得更高的指标值,证明该方法的有效性和优越性。

关键词：强化学习贝叶斯网络维修排故策略生成复杂装备动态动作空间

Analysis of Plant Landscaping Characteristics of the Riverside Park in baoding City of China

在线全文

学校读者我要写书评

暂无评论

Journal of Landscape Research 2012年第7期4卷 24-26,30页

作者： ZHEN Yuehui1,ZHOU Zhengchen1,ZHANG Hongyan2.ZHANG Wenjiao2.1.Common Carrier Bureau of baoding City,baoding,Hebei 071051,China 2.baoding Vocational Technical College,baoding,Hebei 071051,China)

By taking the Riverside Park in baoding City as an example,based on the analysis of the general situation of the park,the paper considers that it should build plant landscape framework according to local condition,so as to manifest temporal and spatial variation and reflect artistic conception of *** characteristic scenic spots with remarkable plant landscaping have been selected for the analysis and research of plant landscaping characteristics,aiming to acquire methods for plants processing in riverside landscape belt *** has pointed out problems existing in riverside plants arrangement and theme's creation,and proposed corresponding reconstruction measures,providing a reference for plant arrangement of urban riverside landscape belt.

关键词： Riverside Park Plant landscaping baoding City

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

多尺度与注意力聚合的隧道点云语义分割方法

测绘科学 2024年第7期49卷 56-65页

作者：黄星霖张星李清泉周宝定深圳大学建筑与城市规划学院深圳大学广东省城市空间信息工程重点实验室深圳大学空间信息智能感知与服务深圳市重点实验室深圳大学自然资源部大湾区地理环境监测重点实验室深圳大学土木与交通工程学院

针对在低照度和弱纹理复杂的隧道环境中，采用三维激光扫描技术采集点云数据，点云语义分割精度难以保障的问题，提出一种基于点云动态图卷积网络改进的隧道点云语义分割网络(TDGCNN)。该网络采用多尺度策略改进边缘卷积层，扩展邻域范... 详细信息

针对在低照度和弱纹理复杂的隧道环境中，采用三维激光扫描技术采集点云数据，点云语义分割精度难以保障的问题，提出一种基于点云动态图卷积网络改进的隧道点云语义分割网络(TDGCNN)。该网络采用多尺度策略改进边缘卷积层，扩展邻域范围，以增强对边缘特征的获取能力；同时，引入两种注意力机制，对特征进行聚合和学习，去除冗余特征。实验结果表明，TDGCNN在隧道点云数据集上的总体精度(OA)达到98.78%,平均交并比(mIoU)为84.95%,表现优于DGCNN、PointNet、PointNet++及GeoSegNet。在WHU-TLS数据集上的验证了TDGCNN对不同隧道场景的鲁棒性，通过消融实验则证实了网络中加入的两种策略的有效性，表明了TDGCNN能有效利用不同层次的特征，提升隧道点云语义分割精度。

关键词：隧道三维点云语义分割多尺度注意力机制