检索结果-南通市图书馆

Nocturnal Migration of Coleoptera:Carabidae in North China

Agricultural sciences in China 2008年第8期7卷 977-986页

作者： ZHANG Yun-hui CHEN Lin CHENG Deng-fa TIAN Zhe SUN Jin-rui JIANG Yu-ying ZHANG Yue-jin State Key Laboratory for Biology of Plant Disease and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China National Agriculture Technique Extension service Centre Beijing 100026 P.R.China

Vertical-looking radar （VLR） has allowed long-term automatic monitoring of the altitudinal and temporal dynamics of high- flying insect populations. To investigate whether ground beetle, insect of Coleoptera, was capable of migrating and its migration pattern by taking advantages of capability of the VLR for long-term real-time automatic monitoring, the migration of Coleoptera ground beetle was investigated by setting up radar observation points, making long-term observation using the VLR and related supplementary equipment, and analyzing low altitude air current and large area circulating current in combination with the meteorological data. Information obtained in 2005 and 2006 showed that the seasonal activities of ground beetles traps of trap lamps were mainly from late June to late August, peak period was mainly in August, seasonal traps of high-altitude lamps and ground lamps were featured by sudden increase and sudden decrease; in peak period, the height of radar echo point could be as high as 600 m, while it was mainly below the height of 450 m; night activities mainly occurred from 20：00 to 22：00, in very few nights, radar echo could last until about 04：00, changes in numbers of ground beetles within the searchlights were consistent with radar echo intensity; ground beetle images were successfully trapped in the sweep nets carried by captive balloons at the height of 200 m. Some species of Carabidaes had some degrees of migration, thus providing the foundation for investigating the migration of Coleoptera insects.

关键词： insect migration radar observation carabid flight behaviour

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Potential Application of Quantitative Prostate-specific Antigen Analysis in forensic Examination of Seminal Stains

引用

Journal of forensic science and Medicine 2015年第2期1卷 159-162页

作者： Zhenping Liu Yang Yang Zhikan Pan Xiaoxu Zhu Shi Feng Dong Zhao Criminal Investigation Detachment Jinhua Bureau of Public SecurityJinhua 321000 Collaborative Innovation Center of Judicial Civilization Key Laboratory of Evidence ScienceChina University of Political Science and LawMinistry of EducationBeijingChina

The aims of this study are to use quantitative analysis of the prostate-specific antigen(PSA)in the seminal stain examination and to explore the practical value of this analysis in forensic *** a comprehensive analysis,vaginal swabs from 48 rape cases were tested both by a PSA fluorescence analyzer(i-CHROMA Reader)and by a conventional PSA strip *** confirm the results of these PSA tests,seminal DNA was tested following differential *** to the PSA strip test,the PSA rapid quantitative fluorescence analyzer provided the more accurate and sensitive *** importantly,individualized schemes based on quantitative PSA results of samples can be developed to improve the quality and procedural efficiency in the forensic seminal inspection of samples prior to DNA analysis.

关键词： forensic biology prostate-specific antigen rapid quantitative fluorescence analyzer semen

来源：

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

Assessment of the 2006-2012 Climatological Fields and Mesoscale Features from Regional Downscaling of CESM Data by WRF-Chem over Southeast Alaska

引用

Atmospheric and Climate sciences 2014年第4期4卷 589-613页

作者： Nicole Molders Cindy L.Bruyère Scott Gende Michael A.Pirhalla Geophysical Institute Department of Atmospheric SciencesCollege of Natural Science and MathematicsUniversity of Alaska FairbanksFairbanksUSA National Center for Atmospheric Research BoulderUSA Environmental sciences and Management North-West UniversityVanderbijlparkSouth Africa National Park service Glacier Bay Field StationJuneauUSA

This case study examined how well downscaling of Community Earth System Model (CESM) data can reproduce climatological conditions relevant for summer (JJA) air quality in Glacier Bay National Park. Climatology was determined from the meteorological results obtained by the Weather Research and Forecasting model inline coupled with chemistry (WRF-chem) when driven with CESM data of 2006-2012. The climatology of this experiment (EXP) was evaluated by climatology from gridded blended sea-wind speeds, CRU data, and 42 surface meteorology sites. The quality relative to known performance was assessed by comparison to climatology determined from WRF-chem control simulations driven with FNL analysis data (CON) in forecast mode. Compared to observations, the thermodynamic and dynamic performances of EXP showed similar shortcomings (dampened diurnal temperature range, overestimation of wind speed over land) as CON. Over water EXP wind-speed climatology JJA bias (simulated minus observed) was -0.7 m/s. With respect to the CRU data EXP biases in JJA 2m temperature, diurnal temperature range, relative humidity and accumulated precipitation were -1.1 K, -4.9 K, 13%, and 110 mm, respectively. The slightly warmer atmosphere in EXP compensated for deficiencies in the cloud schemes leading to better results for the number of wet days and accumulated precipitation than in CON. Downscaling captured known mesoscale responses important for regional climate in a similar way as CON. When using CESM forcing, lateral boundary effects expanded spatially farther into the domain than known for forcing by analysis data. Overall, climatologies obtained from downscaling for Southeast Alaska had similar skill than those derived from forecasts driven by analysis data.

关键词： Evaluation Regional Climate Modeling Downscaling Southeast Alaska WRF-Chem CESM

来源：

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

A deep Q-learning network based active object detection model with a novel training algorithm for service robots

引用

Frontiers of Information Technology & Electronic Engineering 2022年第11期23卷 1673-1683页

作者： Shaopeng LIU Guohui TIAN Yongcheng CUI Xuyang SHAO School of Control science and Engineering Shandong UniversityJinan 250061China

This paper focuses on the problem of active object detection(AOD).AOD is important for service robots to complete tasks in the family environment,and leads robots to approach the target ob ject by taking appropriate moving *** of the current AOD methods are based on reinforcement learning with low training efficiency and testing ***,an AOD model based on a deep Q-learning network(DQN)with a novel training algorithm is proposed in this *** DQN model is designed to fit the Q-values of various actions,and includes state space,feature extraction,and a multilayer *** contrast to existing research,a novel training algorithm based on memory is designed for the proposed DQN model to improve training efficiency and testing *** addition,a method of generating the end state is presented to judge when to stop the AOD task during the training *** comparison experiments and ablation studies are performed based on an AOD dataset,proving that the presented method has better performance than the comparable methods and that the proposed training algorithm is more effective than the raw training algorithm.

关键词： Active object detection Deep Q-learning network Training method service robots

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Radio Resource Allocation for Bidirectional Offloading in Space-Air-Ground Integrated Vehicular Network

引用

Journal of Communications and Information Networks 2019年第4期4卷 24-31页

作者： Guangchao Wang Sheng Zhou Zhisheng Niu Beijing National Research Center for Information science and Technology Department of Electronic EngineeringTsinghua UniversityBeijing 100084China

Aerial platforms and edge servers have been recognized as two promising building blocks to improve the quality of service(QoS)in space-air-ground integrated vehicular networks(SAGIN).Communication intensive tasks can be offloaded to aerial platforms via broadcasting,while computation intensive tasks can be offloaded to ground edge ***,the key issues including how to allocate radio resources and how to determine the task offloading strategy for the two types of tasks,are yet to be *** this paper,the joint optimization of radio resource allocation and bidirectional offloading configuration is *** deal with the non-convex nature of the original problem,we decouple it into a two-step optimization *** the first step,we optimize the bidirectional offloading configuration in the case of the radio resource allocation known in advance,which is proved to be a convex optimization *** the second step,we optimize the radio resource allocation through a brute-force search *** use queuing theories to analyze the average delay of the two tasks with respect to the broadcasting capacity and task arrival *** offloading strategies with closed-form expressions of communication intensive tasks are *** then propose a heuristic algorithm which is shown to perform better than interior point algorithm in *** numerical results also demonstrate that the aerial platforms and edge servers can significantly reduce the average delay of the tasks under different network conditions.

关键词： radio resource allocation bidirectional offloading space-air-ground integrated networks

来源：

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

Secure Synchronization Control for a Class of Cyber-Physical Systems With Unknown Dynamics

引用

IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1215-1224页

作者： Ning Wang Xiaojian Li College of Information science and Engineering Northeastern UniversityShenyang 110819China State Key Laboratory of Synthetical Automation for Process Industries Northeastern Universityand with the Key Laboratory of Vibration and Control of Aero-Propulsion SystemMinistry of EducationNortheastern Universityand also with the College of Information Science and EngineeringNortheastern UniversityShenyang 110819China IEEE

This paper investigates the secure synchronization control problem for a class of cyber-physical systems(CPSs)with unknown system matrices and intermittent denial-of-service(DoS)*** the attack free case,an optimal control law consisting of a feedback control and a compensated feedforward control is proposed to achieve the synchronization,and the feedback control gain matrix is learned by iteratively solving an algebraic Riccati equation(ARE).For considering the attack cases,it is difficult to perform the stability analysis of the synchronization errors by using the existing Lyapunov function method due to the presence of unknown system *** order to overcome this difficulty,a matrix polynomial replacement method is given and it is shown that,the proposed optimal control law can still guarantee the asymptotical convergence of synchronization errors if two inequality conditions related with the DoS attacks ***,two examples are given to illustrate the effectiveness of the proposed approaches.

关键词： Algebraic Riccati equation(ARE) complex dynamical networks(CDNs) denial-of-service(DoS) secure control

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Feasibility of Growing Olives on Selected Sites along Coastal Texas

引用

Journal of Agricultural science and Technology 2011年第2期5卷 139-146页

作者： N. S. A. Malik US Department of Agriculture Agricultural Research Service 2413 E Highway 83 Weslaco Texas 78596 United States

The purpose of this study was to assess the feasibility of growing olives along coastal Texas where the winter temperatures are relatively mild compared to most olive growing regions. For this purpose five sites along the Texas coastline （Seadrift, Galveston, Brazoria, Santa Fe, and Orange） were evaluated for feasibility of growing olives. In addition, two non-coastal sites （Carrizo Springs and Weslaco） were also included in the study for comparative purposes. Flowering and fruiting data were collected during four seasons starting from the 2005-2006 until the 2008-2009 season. In addition to the flowering and fruiting data, half-hourly temperature data were also collected at each site during each season. The results indicate that while olives can grow on all of the sites tested, there is a greater probability of success for commercial growing of olive between and along coastal sites where large scale experiment are highly recommended for rigorous evaluation of potential for commercial production of olives in these areas. In conclusion, there is a good probability that olives could be grown along the northeast coastline of Texas.

关键词： Arbequina flowering fruiting olive Texas.

来源：

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

Optimization design of GaN betavoltaic microbattery

引用

science China(Technological sciences) 2012年第4期55卷 659-664页

作者： TANG XiaoBin LIU YunPeng DING Ding CHEN Da Department of Nuclear science and Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Betavoltaic radioisotope microbatteries have gradually become the research direction of micro-power sources because of their several advantages,including small scale,stable output performance,long service life,high energy density,strong anti-jamming capability,and so *** on the theory of semiconductor physics,the current paper presented a design scheme of isotope microbattery with wide-gap semiconductor material GaN and isotope *** consideration of the isotope's self-absorption effect,the current paper studied and analyzed the optimization thickness of semiconductor and isotope source,junction depth,depletion region thickness,doping concentration,and the generation and collection of electron hole pairs with simulation of transport process of beta particles in semiconductor material using Monte Carlo simulation program *** the proposed design scheme,for a single decay,an average energy of 28.2 keV was deposited in the GaN,and the short circuit current density,open circuit voltage,and efficiency of a single device were 1.636 μA/cm2,3.16 V,and 13.4%,respectively.

关键词： GaN semiconductor isotope battery

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A new family of two-dimensional triple-codeweight asymmetric optical orthogonal code for OCDMA networks

引用

Chinese Optics Letters 2009年第2期7卷 102-105页

作者：殷洪玺梁巍马乐覃丽巧 School of Electronic and Information Engineering Dalian University of Technology State Key Laboratory on Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University

A new generation algorithm of two-dimensional triple-codeweight asymmetric optical orthogonal codes for optical code division multiple access （OCDMA） networks is proposed. The code cardinality is obtained and the error-probability performance for corresponding OCDMA system is analyzed. The codes with two constraints （i.e., auto- and cross-correlation properties） being unequal are taken into account. On the premise of fixed system resources, the code of the error-probability performance, it is shown cardinality can be significantly improved. By analysis that the codes with different parameters have different performances. Therefore, this type of codes can be applied to support diverse quality of service （QoS） and satisfy the quality requirement of different multimedia or distinct users, and simultaneously make the better use of bandwidth resources in oDtical networks.

关键词： Code division multiple access Data communication systems Distributed computer systems Multimedia systems Quality of service Two dimensional

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Efficient Feature Extraction Using Apache Spark for Network Behavior Anomaly Detection

引用

Tsinghua science and Technology 2018年第5期23卷 561-573页

作者： Xiaoming Ye Xingshu Chen Dunhu Liu Wenxian Wang Li Yang Gang Liang Guolin Shao School of Cybersecurity Chengdu University of Information Technology Chengdu 610225 and the College of Computer Science Sichuan University Chengdu 610065 China College of Cybersecurity Sichuan University Chengdu 610065 China School of Management Chengdu University of Information Technology Chengdu 610103 China College of Compute science Sichuan University Chengdu 610065 China

Extracting and analyzing network traffic feature is fundamental in the design and implementation of network behavior anomaly detection methods. The traditional network traffic feature method focuses on the statistical features of traffic volume. However, this approach is not sufficient to reflect the communication pattern features. A different approach is required to detect anomalous behaviors that do not exhibit traffic volume changes, such as low-intensity anomalous behaviors caused by Denial of service/Distributed Denial of service （DoS/DDoS） attacks, Internet worms and scanning, and BotNets. We propose an efficient traffic feature extraction architecture based on our proposed approach, which combines the benefit of traffic volume features and network communication pattern features. This method can detect low-intensity anomalous network behaviors and conventional traffic volume anomalies. We implemented our approach on Spark Streaming and validated our feature set using labelled real-world dataset collected from the Sichuan University campus network. Our results demonstrate that the traffic feature extraction approach is efficient in detecting both traffic variations and communication structure changes. Based on our evaluation of the MIT-DRAPA dataset, the same detection approach utilizes traffic volume features with detection precision of 82.3% and communication pattern features with detection precision of 89.9%. Our proposed feature set improves precision by 94%.

关键词： feature extraction graph theory network behavior anomaly detection Apache Spark

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：