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Cluster based node scheduling method for wireless sensor networks

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Science China(Information Sciences) 2012年第4期55卷 755-764页

作者： WANG Lei 1,2.WEI RuiZhong 2.& TIAN ZiHong 2.3.1 College of Software,{3. University,changsha 410082.China 2.{2. of Computer Science,Lakehead University,Thunder Bay P7B 5E1,Canada 3.Mathematics and Information Science College,Hebei normal University,Shijiazhuang 050016,China College of Software Hunan University department of Computer Science Lakehead University Mathematics and Information Science College Hebei Normal University

By researching on the node scheduling problem of m-covered and connected sensor networks,a new concept of two-hops-cluster is proposed in this paper,and based on it,a new distributed node scheduling algorithm THCNS for allocating all nodes in the sensor network into k(k≤m) different groups {0,1,...,k 1} is designed,without requiring location *** algorithm guarantees that each group to be connected and maintains the coverage ratio with high *** analysis and simulation results show that it has better performance than previous randomized scheduling scheme,and can prolong the lifetime of the sensor network effectively.

关键词： node scheduling lifetime wireless sensor network two-hops-cluster

Effect of excess Y_2._3.addition on the physical properties of melt processed YBCO bulks

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Science China(physics,Mechanics & Astronomy) 2004年第1期47卷 17-23页

作者： YANG Wanmin1,2.3. ZHOU Lian2. FENG Yong2. ZHANG Pingxiang2. WU Minzhi3.& W. GAWALEK3.1. department of physics, Shaanxi {2. University, Xi抋n 710062. China 2. Northwest Institute for Nonferrous Metal Research. Xi抋n 710016, China 3. Institute fur Physikalische Hochtechnologie e.V(IPHT), Jena, Germany Correspondence should be addressed to Yang Wanmin (email: wm-yang@***) Received June 2., 2.03 department of physics Shaanxi Normal University Xi'an 710062 China

The YBCO superconductors with Y2.3.addition were prepared by a modified melt textured process and the effects of excess Y2.3.addition on the physical properties of melt textured YBCO have been investigated. It is found that the melt temperature of YBCO samples decreases drastically with the increasing Y2.3. and the maximum levitation forces are drastically different for samples with different Y2.3.addition. It is also found that the optimal Y2.3.addition to YBCO is about 10wt%. Considering the microstructure and the starting composition, the results are well discussed and interpreted.

关键词： YBCO superconductor, melt growth, Y2.3 addition, levitation force.

STUDY ON PREPARATION AND CATALYTIC ACTIVITY OF A NEW POLYMER LEWIS ACID CATALYST

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Chinese Journal of Reactive Polymers 1993年第2期2卷 107-113页

作者： YU Shanxin and YANG Jianwen (department of Chemistry, hunan {2. University,{3., P.R.China, 410081)

This paper reports the study on the polymer protected catalyst CPVC-FeCl3.used in esterification,transesterification,synthesis of acetals or ketals and rearrangement reaction of *** catalyst has the advantages of bein... 详细信息

关键词：制备催化活性聚合物路易斯酸酯化作用催化剂

Anticoagulation property and security of artificial heart valve material

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Science China(Technological Sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,2., 3. ZHANG Feng2. LI Changrong2. YU Liujiang2. ZHENG Zhihong2. WANG Xi2. JIANG Zhenbin4, CHEN Anqing4 & XU Jingfang3.1. department of physics, East China {2. University, Shanghai 2.0062. China 2. Ion Beam Lab, Shanghai Institute of Mini-system and information, Chinese Academy of Sciences,Shanghai 2.0050, China 3. department of Electronics, School of Information Science and Technology, East China {2. Univer- sity, Shanghai 2.0062. China 4. Shanghai Cardiovascular Institute, Zhongshan Hospital, Shanghai 2.003.0} China Arctic & Antarctic Res Inst Dept Geophys St Petersburg 199226 Russia department of physics East China Normal University Shanghai 200062 China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2.million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.

Time of impact of fragment P2.of comet SL 9 on Jupiter

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Chinese Science Bulletin 1997年第5期42卷 396-398页

作者： ZHOU Hongnan,QIAN Bochen, HUANG Keliang and LI Qibin1. department of Astronomy, Nanjing University, Nanjing 2.0093. China 2. Shanghai Observatory, Chinese Academy of Sciences, Shanghai 2.003., China 3. physics department, Nanjing normal University, Nanjing 2.0097, China 4. Beijing Astronomical Observatory, Chinese Academy of Sciences, Beijing 100080, China department of Astronomy Nanjing University Nanjing China Shanghai Observatory Chinese Academy of Sciences Shanghai China physics department Nanjing Normal University Nanjing China Beijing Astronomical Observatory Chinese Academy of Sciences Behijing China

FROM 1994-07-16 to 1994-07-2., 2. fragments of comet SL 9 impacted against Jupiter in succession. During the impact period the impact of fragments D, E, K, N, P2.and S was observed in China. We used a 1.56-m telescope with the CCD camera of Shanghai Observatory to monitor Jupiter and its Galilean Satellites, obtaining 1000 high-quality images at B, V, I wave bands. Our data on optical wave bands are rather complete and valuable in the world. Specially, we got some images of Jupiter, Io and Europa in the impact time of fragment P2.impacting against Jupiter. This will help us understand the precise time, position, depth and energy of the P2.s collision. In this note, we report the impact time of fragment P2.of comet SL 9 and Jupiter. Since the impact of comet SL 9 was expected to take place on the side of Jupiter

关键词： comet comet Shoemaker-Levy 9 impacting against Jupiter impact time.

Embryonic development and organogenesis of Chinese giant salamander,Andrias davidianus

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Progress in Natural Science:Materials International 2007年第11期17卷 1303-1311页

作者： Luo Jian, Xiao Yamei, Luo Kaikun, Huang Xiaoxi, Peng Liangyue, Liu Yun(Key Laboratory of Protein Chemistry and Fish Developmental Biology of National Education Ministry, College of Life Sciences, hunan normal University,{2., China) Key Laboratory of Protein Chemistry and Fish Developmental Biology of National Education Ministry College of Life Sciences Hunan Normal University Changsha 410081 China

The morphology and organogenesis of Chinese giant salamander, Andrias davidianus, in its different developmental periods and stages are described in detail, which provides an intact criterion for distinguishing different stages of its developmental process. Based on the external morphological and internal histological features, six periods including 2. stages of organogenesis of Chinese giant salamander are established, which are cleavage period, blastula period, gastrula period, neurula period, organogenesis stage and hatching stage. Generally, the embryonic development of Chinese giant salamander is consistent with those of Eastern newt, Cynops orientalis, and Black spots frog, R. nigromaculata. However, they have some differences in the early cleavage process and the development of digestive system. The cleavage of Chinese giant salamander, A. davidianus is not a discoidal division type, which is different from other species reported. And the first three cleavages being meridional and a retardant development of its digestive system without halter and sucker existing are the evident features of the embryonic development of Chinese giant salamander.

关键词： Chinese giant salamander Andrias davidianus embryogenesis cleavage organogenesis

Constraints of f(R) gravity in Palatini approach with observational Hubble data

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Science China(physics,Mechanics & Astronomy) 2011年第8期54卷 1378-1383页

作者： ZHAI ZhongXu & LIU WenBiao department of physics, Institute of Theoretical physics, Beijing {3. University, Beijing 100875, China Beijing normal University Department of Physics Institute of Theoretical Physics Beijing China (GRID:grid.20513.35) (ISNI:***)

We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) gravity in Palatini formalism in which the f(R) form is defined as f(R) = R β/Rn. Under the assumption of a spatially flat FRW universe, we get the best fitting results of the free parameters (Ωm0, n). In the calculation, we marginalize the likelihood function over H0 by integrating the probability density P ∝ e-χ2.2.to obtain the best fitting results and the confidence regions in the Ωm0-n plane. The constraints results of (Ωm0, n) = (0.3., 0.41) by OHD only and (Ωm0, n) = (0.2., 0.08) by the combination of OHD+CMB+BAO both indicate that the universe goes through three last phases, i.e., radiation dominated, matter-dominated, and late time accelerated expansion without introduction of dark energy.

关键词： f(R) gravity OHD CMB BAO accelerating expansion dark energy

CATALYTIC ESTERIFICATION OF CARBOXYLIC ACIDS WITH ALCOHOLS BY SULFO-POLYVINYL CHLORIDE

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Chinese Journal of Reactive Polymers 1993年第2期2卷 182-186页

作者： Yu Shanxin ZHAO Zongbao YANG Jianwen (department of Chemistry, hunan {2. University,{3., China)

Polyvinyl Chloride reacted with chlorosulfonic acid to from a polymer catalyst *** polymer catalyst was found to have high activity for resterification reaction between carboxylic acids and *** paper deals with the conditions in synthesis of n-butlyacetate catalyzed with *** PVC-SO3. was used as a catalyst for preparing 11 esters of acetic acid,propionic acid and butyric acid with the yields of 82.92..

关键词：催化酯化作用羧酸乙醇磺基-聚乙烯氯化物

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基于支持向量回归的无线传感器网络定位算法

通信学报 2009年第10期30卷 44-50页

作者：魏叶华李仁发罗娟付彬湖南师范大学物理与信息科学学院湖南长沙410081 湖南大学计算机与通信学院湖南长沙410082

针对一些增量定位中误差容易累积和集中式算法通信开销较大问题,提出了一种基于支持向量回归的半集中式定位算法,中心节点收集锚节点位置和网络连通信息作为训练样本,使用支持向量回归技术得到连通信息到节点位置的映射函数,分发到普通... 详细信息

针对一些增量定位中误差容易累积和集中式算法通信开销较大问题,提出了一种基于支持向量回归的半集中式定位算法,中心节点收集锚节点位置和网络连通信息作为训练样本,使用支持向量回归技术得到连通信息到节点位置的映射函数,分发到普通节点后即可使用此函数完成自身定位。为增加训练样本,对邻居锚节点达到3.的普通节点,使用基于RSSI测距的最小二乘法进行定位,升级为锚节点。分析和仿真表明,算法减少了通信开销,减轻了测距误差影响,并获取了较高的定位精度。

关键词：无线传感器网络定位支持向量回归最小二乘