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HPSIN: a new hybrid P2P spatial indexing network

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 66-72页

作者： WU jia-gao jiANG Nan ZOU Zhi-qiang HU bin HUANG lin FENG jia-li Institute of Computer Technology Nanjing University of Posts & Telecommunications Nanjing 210003 China Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210046 China School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

Geographic information system （GIS） is increasingly managing very large sets of data, hence a centralized data index may not always provide the most scalable solution. Recently, the peer to peer （P2P） networks have become very popular for sharing information in a totally decentralized manner. In this paper, a new hybrid P2P spatial indexing network （HPSIN） is proposed, which combines distributed quad-tree with distributed Hash table （DHT） based Chord network to maintain both query efficiency and system load balance. In addition, a simple theoretical model based on opened queueing network for HPSIN is established. Assuming each peer as M/M/1 queueing processor in the model, fundamental characteristics of the system is captured, and expression of average query delay is obtained in close form. The theoretical analysis and numerical computing results show that there exists an optimum point of tradeoff between efficiency and load balance. By setting a proper value of start index level ls for different network scale and query rate, HPSIN will achieve the minimum overall query delay, therefore, can adapt to different P2P application environments.

关键词： GIS P2P networks spatial indexing queueing network theory

NUMERICAL SIMULATION OF FLOW AND HEAT TRANSFER CHARA-CTERISTICS OUTSIDE A PERIODICALLY VIBRATING TUBE

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Journal of Hydrodynamics 2008年第5期20卷 629-636页

作者： jiANG Bo TIAN Mao-cheng LENG Xue-li TANG Yu-feng PAN ji-hong School of Energy Source and Power Engineering Shandong University Jinan 250061 China

Fluid flow and heat transfer characteristics outside a vibrating tube were numerically simulated by the dynamic mesh method. The mechanism of heat transfer enhancement via periodic vibration of the tube was explored by using the field synergy principle. It is found that the field synergy angle between fluid velocity vector and temperature gradient vector for a periodically vibrating tube is significantly smaller than that for a stationary tube, and it changes approximately according to the sinusoidal law in a vibration period. The effect of time phase of the vibration on the field synergy angle and convective heat transfer coefficient were also discussed. Results indicate that the vibration can enhance heat transfer and this effect is more remarkable when time phase angle ranges between 50° and 1400 in a half period. Especially when the time phase angle is 90°, the average field synergy angle outside the tube reaches the minimum, which leads to the best heat transfer performance.

关键词： heat transfer enhancement dynamic mesh vibration field synergy Computational Fluid Dynamics (CFD)

Greatly enhanced permittivity in BaTiO_(3)-epoxy dielectric composites with improved connectivity of ceramic phase

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Journal of Materiomics 2021年第1期7卷 1-7页

作者： Meng Cao Lei li Wen bin Hong Shu Ya Wu Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science&EngineeringZhejiang UniversityHangzhou310027China

BaTiO_(3)-epoxy dielectric composites were prepared by curing the liquid epoxy monomer that infiltrated into the partially-sintered BaTiO_(3)porous *** BaTiO_(3)volume fraction of the composites maintained around 58.6%with increasing the sintering temperature from 600℃to 1000°C,while the significant microstructure evolution,improved connectivity of BaTiO_(3)phase and dramatical increase in permittivity from 102 to 697 were *** permittivity and BaTiO_(3)volume fraction further increased to 2328 and 83.5%for the sintering temperature of 1250℃.The present composites had the permittivity 102 orders of magnitude higher than the 0-3 type ones,and the extraordinary results were mainly attributed to the improved connectivity of BaTiO_(3)phase that benefited from partial *** connectivity also had a significant effect on the temperature dependence of permittivity,and good combination of temperature-stable high permittivity,low dielectric loss and relatively low ceramic fraction could be obtained by regulating the connectivity of BaTiO_(3)ceramic phase.

关键词： Ceramic-polymer composite Connectivity High permittivity

Verifiable Secret Sharing Scheme Based on the Plane Parametric Curve

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Applied Mathematics 2021年第11期12卷 1021-1030页

作者： bin li School of Mathematics Chengdu Normal University Chengdu China

Verifiable secret sharing is a special kind of secret sharing. In this paper, A secure and efficient threshold secret sharing scheme is proposed by using the plane parametric curve on the basis of the principle of secret sharing. And the performance of this threshold scheme is analyzed. The results reveal that the threshold scheme has its own advantage of one-parameter representation for a master key, and it is a perfect ideal secret sharing scheme. It can easily detect cheaters by single operation in the participants so that the probability of valid cheating is less than 1/p (where p is a large prime).

关键词： Plane Parameter Curve Threshold Scheme Verifiable Secret Sharing Cheater Information Rate Participating Members

CsPbBr_3 perovskite quantum dots: saturable absorption properties and passively Q-switched visible lasers

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Photonics Research 2017年第5期5卷 457-460页

作者： jiNGZHOU li HONGXING DONG bin XU SAIFENG ZHANG ZHIPING CAI JUN WANG LONG ZHANG Key Laboratory of Materials for High-Power Laser Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Science University of Chinese Academy of Sciences Department of Electronic Engineering Xiamen University IFSA Collaborative Innovation Center Shanghai Jiao Tong University

This work presents the saturable absorption(SA) properties of CsPbBr_3 perovskite quantum dots(QDs). The perovskite QDs show excellent SA performance with a nonlinear absorption coefficient of-35 × 10^(-2) cm∕GW and a figure of merit of 3.7 × 10^(-14) esu cm. Further, their use as saturable absorbers in a passively Q-switched visible solid-state laser for the generation of soliton pulses is demonstrated. These results demonstrate thepotential for the perovskite QDs to act as saturable absorbers.

关键词： QDs Br saturable absorption properties and passively Q-switched visible lasers Pb

A novel algorithm for transmission image reconstruction of tomographic gamma scaners

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Nuclear Science and Techniques 2010年第3期21卷 177-181页

作者： ZHANG Quanhu HUI Weihua WANG Dong HE bin GU Zhongmao li Ze QIAN Shaojun Xi'an Research institute of High-Tech Xi'an 710025 China China Institute of Atomic Energy Beijing 102413 China

It is difficult to develop image reconstruction algorithms for tomographic gamma scanning based on drummed radioactive residues or *** this paper,a novel reconstruction algorithm of transmission image for tomographic gamma scanning is *** is based on the conventional transmission equation and equivalent gamma-ray track length modified by a Monte Carlo *** algorithm is implemented by simulating the samples on the established *** the verification experiments of the algorithm,several cubic voxel samples were designed and *** tests were *** tomographic gamma scanning of transmission images is compared with the linear attenuation coefficients by the simulated values and experimental data with the algorithm and the reference *** results show that the absolute relative errors of the reconstructed images are less than 5%.

关键词：图像重建算法层析γ扫描传输方程蒙特卡罗方法线性衰减系数模拟平台扫描算法伽玛射线

Three antibacterial naphthoquinone analogues from cultured mycobiont of lichen Astrothelium sp

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Chinese Chemical Letters 2010年第7期21卷 842-845页

作者： li Yan Sun Zhen liang liu Tao Zhang Shu bin Niu Zun Tian Zhao College of Pharmacology Taishan Medical UniversityTaian 271016China College of life Sciences Shandong Normal UniversityJinan 250014China College of Chemistry and Chemical Engineering Taishan Medical UniversityTaian 271016China Key Lab of Systematic Mycology & lichenology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

A new naphthoquinone compound named 7-hydroxyl-8-methoxyltrypethelone 3 together with two known compounds trypethelone 1 and trypethelone methyl ether 2 was isolated from cultured mycobiont of Astrothelium *** structures were elucidated by 1D and 2D NMR spectroscopic analysis as well as comparison with those reported in *** 1 displayed significant antibacterial activity against Bacillus subtilis（ATCC 6633）,and showed modest antibacterial activity against Staphylococcus aureus col（MRSA）（CGMCC 1.2465）,while compounds 2 and 3 showed modest antibacterial activity against Enterococcus faecalis 850E（CGMCC 1.2135） and *** col（MRSA）（CGMCC 1.2465）.

关键词： Astrothelium sp. lichen Mycobiont 7-Hydroxyl-8-methoxyltrypethelone

Pm21, Encoding a Typical CC-NBS-LRR Protein, Confers Broad-Spectrum Resistance to Wheat Powdery Mildew Disease

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Molecular Plant 2018年第6期11卷 879-882页

作者： Huagang He Shanying Zhu Renhui Zhao Zhengning jiang Yaoyong ji jian ji Dan Qiu Hongjie li Tongde Bie School of Food and Biological Engineering Jiangsu University Zhenjiang Jiangsu 212013 China School of Environment Jiangsu University Zhenjiang Jiangsu 2120131 China Key Laboratory of Wheat Biology and Genetic Improvement on Low & Middle Yangtze River Valley Wheat Region (Ministry of Agriculture) Yangzhou Academy of Agricultural Sciences Yangzhou Jiangsu 225007 China National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI) Institute of Crop Science Chinese Academy of Agricultural Sciences Beijing 100081 China

Dear Editor, Common wheat （Triticum aestivum, 2n = 6x = 42, AABBDD） is one of the most widely cultivated cereal crops, providing -20% of the calories consumed by humans （Fu et al., 2009）. However, wheat production is constantly challenged by powdery mildew disease, which occurs globally and is caused by the biotrophic fungal pathogen Blumena graminis f. sp. tritici （Bgt）. Utilization of powdery mildew resistance （Pm） genes is the most effective and economical way to control powdery mildew disease.

关键词： Pm21 疾病蛋白质小麦粉编码用途普通小麦小麦生产

Equal compressibility structural phase transition of molybdenum at high pressure

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Chinese Physics B 2022年第11期31卷 412-415页

作者： Lun Xiong bin li Fang Miao Qiang li Guangping Chen jinxia Zhu Yingchun Ding Duanwei He School of Intelligent Manufacturing Sichuan University of Arts and ScienceDazhou 635000China DaZhou Industrial Technology Institute of Intelligent Manufacturing Dazhou 635000China College of Optoelectronics Engineering Chengdu University of Information TechnologyChengdu 610225China Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Key Laboratory of High Energy Density Physics and Technology of Ministry of Education Sichuan UniversityChengdu 610065China

We have studied the high-pressure compression behavior of molybdenum up to 60 GPa by synchrotron radial x-ray diffraction(RXRD)in a diamond anvil cell(DAC).It is found that all diffraction peaks of molybdenum undergo a split at around 27 GPa,and we believe that a phase transition from a body-centered cubic structure to a rhombohedral structure at room pressure has *** slope of pressure–volume curve shows continuity before and after this phase transition,when fitting the pressure–volume curves of the body-centered cubic structure at low pressure and the rhombohedral structure at high pressure.A bulk modulus of 261.3(2.7)GPa and a first-order derivative of the bulk modulus of 4.15(0.14)are obtained by using the nonhydrostatic compression data at the angleψ=54.7°between the diffracting plane normal and stress axis.

关键词： molybdenum high pressure phase transition radial x-ray diffraction diamond anvil cell