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A Localization Method of High Energy Transients for All-sky Gamma-ray Monitor

2012 National Conference on Information technology and Computer science

Due to the increasing of the population and development of industry economy,many Peasant Family Gardens have been flocking to the Sichuan Basin and shows messy distribution pattern on spatial *** the present paper,total of 187 Peasant Family Gardens in the Xindu District,chengdu City,are selected as the focus of the *** Spatial Analysis and Geo-statistical Analysis of the ArcGIS software are used to analyze the distribution regularity of the Peasant Family Garden,and then to explore the contributory factors leading to the messy distribution *** results show that the spatial distribution pattern of Peasant Family Garden belongs to *** are five cluster zones of the Peasant Family Garden in Xindu *** spatial distribution of the Peasant Family Gardens is relatively dense with the buffer distance from 2 to 6km.

关键词： component the Peasant Family Garden,Spatial analysis,Geo-statistical analysis,the Xindu District

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Research in Astronomy and Astrophysics 2024年第10期24卷 25-35页

作者： Yi Zhao Wangchen Xue Shaolin Xiong Qi Luo Yuanhao Wang Jiacong Liu Heng Yu Xiaoyun Zhao Yue Huang Jinyuan Liao Jianchao Sun Xiaobo Li Qibin Yi Ce Cai Shuo Xiao Shenglun Xie chao zheng Yanqiu Zhang Chenwei Wang Wenjun Tan Zhiwei Guo chaoyang Li zhenghua An Gang Chen Yanqi Du Min Gao Ke Gong Dongya Guo Jiang He Jianjian He Bing Li Gang Li Xinqiao Li Jing Liang Xiaohua Liang Yaqing Liu Xiang Ma Rui Qiao Liming Song Xinying Song Xilei Sun Jin Wang Ping Wang Xiangyang Wen hong Wu Yanbing Xu Sheng Yang Dali Zhang Fan Zhang hongmei Zhang Peng Zhang Shu Zhang Zhen Zhang Shijie zheng Keke Zhang Xingbo Han Haiyan Wu Hu Tai Hao Geng Gaopeng Lu Wei Xu Fanchao Lyu hongbo Zhang Fangjun Lu Shuangnan Zhang Department of Astronomy Beijing Normal UniversityBeijing 100875China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of sciences Beijing 100049China school of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China College of Physics Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China school of Physics and electronic science Guizhou Normal UniversityGuiyang 550001China Institute of Astrophysics Central China Normal UniversityWuhan 430079China College of physics sciences technology Hebei UniversityBaoding 071002China Physics and Space science College China West Normal UniversityNanchong 637002China school of Computing and Artificial Intelligence Southwest Jiaotong UniversityChengdu 611756China College of electronic and information Engineering Tongji UniversityShanghai 201804China Innovation Academy for Microsatellites of Chinese Academy of sciences Shanghai 201304China National Space science Center Chinese Academy of SciencesBeijing 100190China school of Earth and Space sciences University of Science and Technology of ChinaHefei 230026China electronic Information school Wuhan UniversityWuhan 430072China Key Laboratory of Transportation Meteorology of china Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210000China Key Laboratory of Middle Atmosphere and Global environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up *** based on the relative counts of different detectors has been widely used for all-sky gamma-ray *** are two major methods for this count distribution localization:χ^(2)minimization method and the Bayesian *** we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the χ^(2)*** comprehensive simulations,we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than the χ^(2)method,especially for weak *** further proposed a location-spectrum iteration approach based on the Bayesian inference,which could alleviate the problems caused by the spectral difference between the burst and location *** method is very suitable for scenarios with limited computation resources or timesensitive applications,such as in-flight localization software,and low-latency localization for rapidly follow-up observations.

关键词： methods:data analysis methods:analytical (stars:)gamma-ray burst:general

High energy storage density in NaNbO_(3) antiferroelectrics with double hysteresis loop

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Journal of Materiomics 2024年第5期10卷 1026-1035页

作者： Li Ma Zhenpei Chen Gengguang Luo Zhiyi Che chao Xu Dongliang Shan Zhenyong Cen Qin Feng Xiyong Chen Toyohisa Fujita Ye Zhu Yunya Liu Jing-Feng Li Shujun Zhang Nengneng Luo State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures School of ResourcesEnvironment and MaterialsGuangxi UniversityNanning530004China school of Chemistry and Chemical Engineering Guangxi UniversityNanning530004China Department of Applied Physics Research Institute for Smart EnergyThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Key Laboratory of Low Dimensional Materials and Application technology of Ministry of Education School of Materials Science and EngineeringXiangtan UniversityXiangtan411105HunanChina State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Institute for Superconducting and electronic Materials Australian Institute of Innovative MaterialsUniversity of WollongongWollongongNSW2500Australia

Antiferroelectrics(AFEs)possess great potential for high performance dielectric capacitors,due to their distinct double hysteresis loop with high maximum polarization and low remnant ***,the well-known NaNbO3 lead-free antiferroelectric(AFE)ceramic usually exhibits square-like P–E loop related to the irreversible AFE P phase to ferroelectric(FE)Q phase transition,yielding low recoverable energy storage density(Wrec).Herein,significantly improved Wrec up to 3.3 J/cm^(3) with good energy storage efficiency(η)of 42.4% was achieved in Na_(0.7)Ag_(0.3)Nb_(0.7)Ta_(0.3)O_(3)(30Agsingle bond30Ta)ceramic with well-defined double P–E loop,by tailoring the A-site electronegativity with Ag+and B-site polarizability with Ta^(5+).The Transmission Electron Microscope,Piezoresponse Force Microscope and in-situ Raman spectra results verified a good reversibility between AFE P phase and high-field-induced FE Q *** improved stability of AFE P phase,being responsible for the double P–E loop and improved Wrec,was attributed to the decreased octahedral tilting angles and cation *** mechanism was revealed by synchrotron X-ray diffraction and Scanning Transmission Electron *** work provides a good paradigm for achieving double P–E loop and high energy storage density in NaNbO_(3)-based ceramics.

关键词： Sodium niobate Antiferroelectrics Double hysteresis loop Energy storage performance Reversibility

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保温瓶真空失效快速检验方法及实现

工程热物理学报 2024年第7期45卷 2054-2060页

作者：丁思淇王宇君彭嘉乐蓝威邓超魏福龙罗小兵华中科技大学能源与动力工程学院武汉430074

测井仪用于探测地底油气资源,面临高达200℃的井下环境,为防止内部电子器件超温失效,采用保温瓶对其进行隔热。然而,由于井下高温高压、腐蚀振动等恶劣环境,且保温瓶真空层内部结构复杂、焊接强度有限,存在真空失效的风险,因而下井作业... 详细信息

测井仪用于探测地底油气资源,面临高达200℃的井下环境,为防止内部电子器件超温失效,采用保温瓶对其进行隔热。然而,由于井下高温高压、腐蚀振动等恶劣环境,且保温瓶真空层内部结构复杂、焊接强度有限,存在真空失效的风险,因而下井作业前需要对保温瓶进行检验。针对这一问题,本文首先设计了一套保温瓶真空失效快速检验装置,确定了判断指标P值,用数值仿真验证了P值的稳定性,并计算得到了判断保温瓶正常和真空失效的临界值Pe为0.351。随后搭建测试台架进行了实验验证,结果表明,真空失效前后的P值误差均不超过10%,稳定性良好。最后,对该装置的控制系统进行了集成设计,实现了对保温瓶真空失效与否的快速精准判断。

关键词：测井仪保温瓶真空失效快速检验

A multiobjective evolutionary optimization method based critical rainfall thresholds for debris flows initiation

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Journal of Mountain science 2020年第8期17卷 1860-1873页

作者： YAN Yan ZHANG Yu HU Wang GUO Xiao-jun MA chao WANG Zi-ang ZHANG Qun Key Laboratory of High-Speed Railway Engineering MOE/School of Civil EngineeringSouthwest Jiao tong UniversityChengdu 610031China Institute of Geographic sciences and Natural resources Research Chinese Academy of SciencesBeijing 100101China school of Computer science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Key Laboratory of Mountain Surface Process and Hazards/Institute of Mountain Hazards and environment Chinese Academy of SciencesChengdu 610041China school of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Sichuan Institute of Land and Space Ecological Restoration and Geological Hazard Prevention Chengdu 610081China

At present,most researches on the critical rainfall threshold of debris flow initiation use a linear model obtained through *** relatively weak fault tolerance,this method not only ignores nonlinear effects but also is susceptible to singular noise samples,which makes it difficult to characterize the true quantization relationship of the rainfall ***,the early warning threshold determined by statistical parameters is susceptible to negative samples(samples where no debris flow has occurred),which leads to uncertainty in the reliability of the early warning results by the regression *** overcome the above limitations,this study develops a data-driven multiobjective evolutionary optimization method that combines an artificial neural network(ANN)and a multiobjective evolutionary optimization implemented by particle swarm optimization(PSO).Firstly,the Pareto optimality method is used to represent the nonlinear and conflicting critical thresholds for the rainfall intensity I and the rainfall duration *** ANN is used to construct a dual-target(dual-task)predictive surrogate model,and then a PSO-based multiobjective evolutionary optimization algorithm is applied to train the ANN and stochastically search the trained ANN for obtaining the Pareto front of the I-D surrogate prediction model,which is intended to overcome the limitations of the existing linear regression-based threshold ***,a double early warning curve model that can effectively control the false alarm rate and negative alarm rate of hazard warnings are proposed based on the decision space and target space *** study provides theoretical guidance for the early warning and forecasting of debris flows and has strong applicability.

关键词： Debris flow Critical rainfall thresholds Multiobjective evolutionary optimization Artificial neural network Pareto optimality

基于波段定制高像素无人机多光谱相机的陆浑水库水质参数反演研究

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遥感技术与应用 2024年第1期39卷 160-169页

作者：高敏李潇屹王超董韬陈玥张方方王胜蕾刘改芝李俊生中国地质大学(北京) 地球科学与资源学院北京100083 中国科学院空天信息创新研究院数字地球重点实验室北京100094 航天数维高新技术股份有限公司北京100070 河南省科学院地理研究所河南省遥感与GIS重点实验室河南郑州450052 可持续发展大数据国际研究中心北京100094 陆浑湖国家湿地公园管理处河南嵩县471400 中国科学院大学电子电气与通信工程学院北京100049

无人机载多光谱遥感在小型水体水环境监测中具有成本低、时间灵活等优势,但是常见的多光谱相机具有像素数量低、缺少内陆水体特征波段等问题,限制了无人机多光谱遥感在水环境监测中优势的发挥。针对这些问题,研究定制了面向内陆水体水... 详细信息

无人机载多光谱遥感在小型水体水环境监测中具有成本低、时间灵活等优势,但是常见的多光谱相机具有像素数量低、缺少内陆水体特征波段等问题,限制了无人机多光谱遥感在水环境监测中优势的发挥。针对这些问题,研究定制了面向内陆水体水质监测的高像素航天数维KP-8多光谱相机,相机包括面向内陆水体叶绿素a反演的670和700 nm波段;利用无人机飞行实验获取了浑浊富营养化的陆浑水库的多光谱影像,并利用同步水面实验获取的水质参数构建了典型水质参数透明度、浊度、悬浮物和叶绿素a浓度反演模型;将反演模型应用于多光谱影像,反演并分析了陆浑水库典型水质参数空间分布规律。结果表明:这种波段定制的高像素无人机多光谱相机在内陆水体水环境业务化监测方面具有重要潜力。

关键词：无人机多光谱波段定制水质参数

A Method for Trust Management in Cloud Computing: Data Coloring by Cloud Watermarking

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International Journal of Automation and computing 2011年第3期8卷 280-285页

作者： Yu-chao Liu Yu-Tao Ma Hai-Su Zhang De-Yi Li Gui-Sheng Chen Department of Computer science and technology Tsinghua University Beijing 100084 PRC Institute of electronic System Engineering Beijing 100141 PRC State Key Lab of Software Engineering Wuhan University Wuhan 430072 PRC school of Command Automation PLA University of Science and Technology Nanjing 210007 PRC

With the development of Internet technology and human computing, the computing environment has changed dramatically over the last three decades. Cloud computing emerges as a paradigm of Internet computing in which dynamical, scalable and often virtuMized resources are provided as services. With virtualization technology, cloud computing offers diverse services （such as virtual computing, virtual storage, virtual bandwidth, etc.） for the public by means of multi-tenancy mode. Although users are enjoying the capabilities of super-computing and mass storage supplied by cloud computing, cloud security still remains as a hot spot problem, which is in essence the trust management between data owners and storage service providers. In this paper, we propose a data coloring method based on cloud watermarking to recognize and ensure mutual reputations. The experimental results show that the robustness of reverse cloud generator can guarantee users＇ embedded social reputation identifications. Hence, our work provides a reference solution to the critical problem of cloud security.

关键词： Cloud computing cloud security trust management cloud watermarking data coloring.

Application of graph neural network and feature information enhancement in relation inference of sparse knowledge graph

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Journal of electronic science and technology 2023年第2期21卷 44-54页

作者： Hai-Tao Jia Bo-Yang Zhang chao Huang Wen-Han Li Wen-Bo Xu Yu-Feng Bi Li Ren school of resources and environment University of Electronic Science and Technology of ChinaChengdu611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou313001China Sichuan Jiuqiang Communication technology Co.Ltd. Mianyang621000China school of Marxism University of Electronic Science and Technology of ChinaChengdu611731China

At present,knowledge embedding methods are widely used in the field of knowledge graph(KG)reasoning,and have been successfully applied to those with large entities and ***,in research and production environments,there are a large number of KGs with a small number of entities and relations,which are called sparse *** by the performance of knowledge extraction methods or some other reasons(some common-sense information does not appear in the natural corpus),the relation between entities is often *** solve this problem,a method of the graph neural network and information enhancement is *** improved method increases the mean reciprocal rank(MRR)and Hit@3 by 1.6%and 1.7%,respectively,when the sparsity of the FB15K-237 dataset is 10%.When the sparsity is 50%,the evaluation indexes MRR and Hit@10 are increased by 0.8%and 1.8%,respectively.

关键词： Feature information enhancement Graph neural network Natural language processing Sparse knowledge graph(KG)inference

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电弧射流激励器光谱诊断研究

中国光学（中英文） 2023年第2期16卷 296-304页

作者：袁野田雷超郭成赵青电子科技大学资源与环境学院四川成都610054 上海空间推进研究所上海空间发动机工程技术研究中心上海201112

目前,电弧激励器的仿真研究仅局限于得到激励器产生的等离子体的电势、压力、温度和速度等工作特性,而其有关的等离子体状态参数仅限于用光谱诊断其电子温度和电子密度等,二者是分立的,本文试图将其二者统一起来。本文设计了电弧射流等... 详细信息

目前,电弧激励器的仿真研究仅局限于得到激励器产生的等离子体的电势、压力、温度和速度等工作特性,而其有关的等离子体状态参数仅限于用光谱诊断其电子温度和电子密度等,二者是分立的,本文试图将其二者统一起来。本文设计了电弧射流等离子体激励器,采用有限元法求解非线性多物理场方程,对此电弧射流等离子体激励器的工作特性进行了数值模拟,得到了激励器内部的电势、压力、温度和速度分布,并在此基础上计算了电子密度,由激励器工况得到了激励器等离子体状态参数(电子温度和电子密度)的仿真计算模型。然后采用发射光谱诊断方法对射流等离子体进行了光谱诊断,利用分立谱线的强度比例法对等离子体电子密度进行计算。结果表明:电弧等离子体激励器诊断实验得到的最高电子温度为10 505.8 K,最大电子密度为5.75×1022m-3。对于不同工况下的等离子体电子温度和等离子体密度,实验和仿真结果数值均随入口气体流量增大及放电电流的增大而增大。表明对于所设计的小型化、高射流速度的电弧射流激励器等离子体状态参数的仿真计算模型是合理且适用的。说明将激励器工作特性仿真与光谱诊断的电子温度、密度统一考虑是基本成功的,同时还有值得进一步改进的地方。

关键词：发射光谱光谱学电子密度电弧激励器