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A STUDY OF SOIL CONSERVATION MONITORING INFORMATION SYSTEM BASED ON REMOTELY SENSED DATA FOR A CATCHMENT ON THE LOESS PLATEAU
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作者 Li Rui, Li Bichen, Ma Xiaoyun (Northwesterng Institute of Soil and Water Conservation, Academia Sinica and Ministry of Water Resources) 《遥感信息》 CSCD 1990年第A02期41-42,共2页
The Soil Conservation Monitorins Information System (SCMIS) presented in this paper is oriented to soil erosion control, resources exploitation, utilization, planning and management for a small watershed (about 10 sq.... The Soil Conservation Monitorins Information System (SCMIS) presented in this paper is oriented to soil erosion control, resources exploitation, utilization, planning and management for a small watershed (about 10 sq. km.) on the Loess Plateau. It sums up Remote sensing (RS), Geographical Information System (GIS) and Expert System (ES) and consists of a integrated system. As a basic level information system of Loess Plateau, its perfection and psreading will bring about a great advance in resources exploitation and management of Loess Plateau. 展开更多
关键词 SCMIS A STUDY OF SOIL CONSERVATION MONITORING INFORMATION system baseD ON REMOTELY SENSED data FOR A CATCHMENT ON THE LOESS PLATEAU GIS data
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Development of a tracking-based system for automated traffic data collection for roundabouts
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作者 Hai Dinh Hua Tang 《Journal of Modern Transportation》 2017年第1期12-23,共12页
Traffic data collection is essential for performance assessment, safety improvement and road planning. While automated traffic data collection for highways is relatively mature, that for roundabouts is more challengin... Traffic data collection is essential for performance assessment, safety improvement and road planning. While automated traffic data collection for highways is relatively mature, that for roundabouts is more challenging due to more complex traffic scenes, data specifications and vehicle behavior. In this paper, the authors propose an automated traffic data collection system dedicated to roundabout scenes. The proposed system has mainly four steps of processing. First, camera calibration is performed for roundabout traffic scenes with a novel circle-based calibration algorithm. Second, the system uses enhanced Mixture of Gaussian algorithm with shaking removal for video segmentation, which can tolerate repeated camera displacements and background movements. Then, Kalman filtering, Kemel-based tracking and overlap-based opti- mization are employed to track vehicles while they are occluded and to derive the complete vehicle trajectories. The resulting vehicle trajectory of each individual vehicle gives the position, size, shape and speed of the vehicle at each time moment. Finally, a data mining algorithm is used to automatically extract the interested traffic data from the vehicle trajectories. The overall traffic data collection system has been implemented in software and runs on regular PC. The total processing time for a 3-hour video is currently 6 h. The automated traffic data collection system can significantly reduce cost and improve efficiency compared to manual data collection. The extracted traffic data have been compared to accurate manual measurements for 29 videos recorded on 29 different days, and an accuracy of more than 90% has been achieved. 展开更多
关键词 Traffic data collection Vehicle tracking ROUNDABOUT Vision-based systems Intelligent transportsystems
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Web-based GIS System for Real-time Field Data Collection Using Personal Mobile Phone 被引量:2
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作者 Ko Ko Lwin Yuji Murayama 《Journal of Geographic Information System》 2011年第4期382-389,共8页
Recently, use of mobile communicational devices in field data collection is increasing such as smart phones and cellular phones due to emergence of embedded Global Position System GPS and Wi-Fi Internet access. Accura... Recently, use of mobile communicational devices in field data collection is increasing such as smart phones and cellular phones due to emergence of embedded Global Position System GPS and Wi-Fi Internet access. Accurate timely and handy field data collection is required for disaster management and emergency quick responses. In this article, we introduce web-based GIS system to collect the field data by personal mobile phone through Post Office Protocol POP3 mail server. The main objective of this work is to demonstrate real-time field data collection method to the students using their mobile phone to collect field data by timely and handy manners, either individual or group survey in local or global scale research. 展开更多
关键词 WEB-baseD GIS system REAL-TIME Field data Collection PERSONAL Mobile PHONE POP3 MAIL Server
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A Rule Management System for Knowledge Based Data Cleaning
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作者 Louardi BRADJI Mahmoud BOUFAIDA 《Intelligent Information Management》 2011年第6期230-239,共10页
In this paper, we propose a rule management system for data cleaning that is based on knowledge. This system combines features of both rule based systems and rule based data cleaning frameworks. The important advantag... In this paper, we propose a rule management system for data cleaning that is based on knowledge. This system combines features of both rule based systems and rule based data cleaning frameworks. The important advantages of our system are threefold. First, it aims at proposing a strong and unified rule form based on first order structure that permits the representation and management of all the types of rules and their quality via some characteristics. Second, it leads to increase the quality of rules which conditions the quality of data cleaning. Third, it uses an appropriate knowledge acquisition process, which is the weakest task in the current rule and knowledge based systems. As several research works have shown that data cleaning is rather driven by domain knowledge than by data, we have identified and analyzed the properties that distinguish knowledge and rules from data for better determining the most components of the proposed system. In order to illustrate our system, we also present a first experiment with a case study at health sector where we demonstrate how the system is useful for the improvement of data quality. The autonomy, extensibility and platform-independency of the proposed rule management system facilitate its incorporation in any system that is interested in data quality management. 展开更多
关键词 RULE data Quality data CLEANING KNOWLEDGE RULE Management system RULE based system Structure
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A Model-free Approach to Fault Detection of Continuous-time Systems Based on Time Domain Data
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作者 Steven X. Ding 《International Journal of Automation and computing》 EI 2007年第2期189-194,共6页
In this paper, a model-free approach is presented to design an observer-based fault detection system of linear continuoustime systems based on input and output data in the time domain. The core of the approach is to d... In this paper, a model-free approach is presented to design an observer-based fault detection system of linear continuoustime systems based on input and output data in the time domain. The core of the approach is to directly identify parameters of the observer-based residual generator based on a numerically reliable data equation obtained by filtering and sampling the input and output signals. 展开更多
关键词 Fault detection linear continuous time-invariant systems time domain data subspace methods observer-based residual generator
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Construction of Free Amino Acids Composition Data Base for Food
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作者 Hinako Ito Hiroshi Ueno 《Journal of Chemistry and Chemical Engineering》 2014年第5期501-515,共15页
Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information... Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information of free amino acids in food, we have carried out the experiments to quantitate the free amino acids by derivatized with NBD-F (4-fluoro-7-nitrobenzofurazan) and analyzed on reversed-phase UHPLC (ultra-high pressure liquid chromatography) equipped with ultraviolet visible detector. Almost all of food extracts contained free amino acids including GABA (T-amino butyrate). Contents of free amino acids vary considerably depending upon vegetables and fruits. Principal free amino acids found in vegetables and fruits were asparagine, glutamine, arginine and GABA, which are involved in important metabolic pathways in human. About 140 species of vegetables and fruits were subjected for the data base. All of the plants and fruits we examined exhibit significant amount of free amino acids, those are clearly distinct from data bases obtained after acid hydrolysis treated food samples. Since glutamate and GABA act as excitatory and inhibitory neurotransmitters in CNS, respectively; free amino acids in vegetables and fruits that we eat daily, should be an important source for the cellular metabolic activities. 展开更多
关键词 Free amino acid GABA data base FOOD UHPLC.
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The 8×10 GHz Receiver Optical Subassembly Based on Silica Hybrid Integration Technology for Data Center Interconnection 被引量:3
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作者 Chao-Yi Li Jun-Ming An +8 位作者 Jiu-Qi Wang Liang-Liang Wang Jia-Shun Zhang Jian-Guang Li Yuan-Da Wu Yue Wang Xiao-Jie Yin Yong Li Fei Zhong 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期39-43,共5页
An 8×10 GHz receiver optical sub-assembly (ROSA) consisting of an 8-channel arrayed waveguide grating (AWG) and an 8-channel PIN photodetector (PD) array is designed and fabricated based on silica hybrid in... An 8×10 GHz receiver optical sub-assembly (ROSA) consisting of an 8-channel arrayed waveguide grating (AWG) and an 8-channel PIN photodetector (PD) array is designed and fabricated based on silica hybrid integration technology. Multimode output waveguides in the silica AWG with 2% refractive index difference are used to obtain fiat-top spectra. The output waveguide facet is polished to 45° bevel to change the light propagation direction into the mesa-type PIN PD, which simplifies the packaging process. The experimentM results show that the single channel I dB bandwidth of AWG ranges from 2.12nm to 3.06nm, the ROSA responsivity ranges from 0.097 A/W to 0.158A/W, and the 3dB bandwidth is up to 11 GHz. It is promising to be applied in the eight-lane WDM transmission system in data center interconnection. 展开更多
关键词 AWG GHz Receiver Optical Subassembly based on Silica Hybrid Integration Technology for data Center Interconnection The 8 PD
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Makran Coastal Zoning for the Construction of New Marine Areas based on Hydrological and Hydraulic Characteristics Using Satellite Data and Spatial Analysis
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作者 Hossein Khanzadi Karim Akbari Vakilabadi Ramin Almasi 《Sustainable Marine Structures》 2020年第2期25-34,共10页
On one hand,the diversity of activities and on the other hand,the conflicts between beneficiaries necessitate the efficient management and supervision of coastal areas.Accordingly,monitoring and evaluation of such are... On one hand,the diversity of activities and on the other hand,the conflicts between beneficiaries necessitate the efficient management and supervision of coastal areas.Accordingly,monitoring and evaluation of such areas can be considered as a critical factor in the national development and directorship of the sources.With regard to this fact,remote sourcing technologies with use of analytical operations of geographic information systems(GIS),will be remarkably advantageous.Iran’s south-eastern Makran coasts are geopolitically and economically,of importance due to their strategic characteristics but have been neglected and their development and transit infrastructure are significantly beyond the international standards.Therefore,in this paper,with regard to the importance of developing Makran coasts,a Multi-Criterion Decision Analysis(MCDA)method was applied to identify and prioritize the intended criteria and parameters of zoning,in order to establish new maritime zones.The major scope of this study is to employ the satellite data,remote sensing methods,and regional statistics obtained from Jask synoptic station and investigate the region’s status in terms of topography,rainfall rate and temperature changes to reach to a comprehensive monitoring and zoning of the coastal line and to provide a pervasive local data base via use of GIS and MCDA,which will be implemented to construct the coastal regions.In this article,while explaining the steps of coastal monitoring,its main objectives are also explained and the necessary procedures for doing so are presented.Then,the general steps of marine climate identification and study of marine parameters are stated and the final achievements of the coastal monitoring process are determined.In the following,considering that this article focuses on the monitoring of Makran beaches,the method of work in the mentioned region will be described and its specific differences and complexities will be discussed in detail.Also,the impact of such projects on future research results will be discussed. 展开更多
关键词 Makran coasts Multi-criterion decision analysis ZONING Local data base
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Research and strategy employment information based on extension data mining
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作者 Xihua zhang 《International Journal of Technology Management》 2015年第11期14-15,共2页
This paper uses the extension theory of knowledge, probes into the problems of students employment of College of computer science, puts forward to the solving method,specific and provides corresponding strategies. At ... This paper uses the extension theory of knowledge, probes into the problems of students employment of College of computer science, puts forward to the solving method,specific and provides corresponding strategies. At the same time, it carries on the appraisal to provide strategy, put forward to optimal strategies; it uses of baseing on extension data mining and mining association rules of the corresponding and finding the meaning relations existing in enterprise recruitment, 展开更多
关键词 Extentics Strategy generating based on extension data mining
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Global Statistical Study of Ionospheric Waves Based on COSMIC GPS Radio Occultation Data
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作者 Xuan-Yun Zeng Xiang-Hui Xue +4 位作者 Xin-An Yue Ming-Jiao Jia Bing-Kun Yu ian-Fei Wu Chao Yu 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第10期93-97,共5页
Extracting and parameterizing ionospheric waves globally and statistically is a longstanding problem. Based on the multichannel maximum entropy method(MMEM) used for studying ionospheric waves by previous work, we c... Extracting and parameterizing ionospheric waves globally and statistically is a longstanding problem. Based on the multichannel maximum entropy method(MMEM) used for studying ionospheric waves by previous work, we calculate the parameters of ionospheric waves by applying the MMEM to numerously temporally approximate and spatially close global-positioning-system radio occultation total electron content profile triples provided by the unique clustered satellites flight between years 2006 and 2007 right after the constellation observing system for meteorology, ionosphere, and climate(COSMIC) mission launch. The results show that the amplitude of ionospheric waves increases at the low and high latitudes(~0.15 TECU) and decreases in the mid-latitudes(~0.05 TECU). The vertical wavelength of the ionospheric waves increases in the mid-latitudes(e.g., ~50 km at altitudes of 200–250 km) and decreases at the low and high latitudes(e.g., ~35 km at altitudes of 200–250 km).The horizontal wavelength shows a similar result(e.g., ~1400 km in the mid-latitudes and ~800 km at the low and high latitudes). 展开更多
关键词 COSMIC Global Statistical Study of Ionospheric Waves based on COSMIC GPS Radio Occultation data GPS
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Research of Graduation Project Management System Based on B/S Mode
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作者 Ai-Mei XIAO Yan-Feng CAO 《通讯和计算机(中英文版)》 2014年第7期559-564,共6页
关键词 管理系统 毕业设计 S模式 管理人员 项目申请 项目选择 学生 教师
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Mosaic Maps of China in Different Seasons Based on Data from HJ-1A/1B Satellites
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《Aerospace China》 2010年第1期F0003-F0003,共1页
关键词 MAPS HJ Mosaic Maps of China in Different Seasons based on data from HJ-1A/1B Satellites
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Analysis of sea level changes in the Caspian Sea related to Cosmo-geophysical processes based on satellite and terrestrial data
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作者 Vladimir Kaftan Boris Komitov Sergey Lebedev 《Geodesy and Geodynamics》 2018年第6期449-455,共7页
Analysis results of the average annual sea levels in the Caspian Sea obtained from ground and satellite observations, corresponding to solar activity characteristics, magnetic field data, and length of day are present... Analysis results of the average annual sea levels in the Caspian Sea obtained from ground and satellite observations, corresponding to solar activity characteristics, magnetic field data, and length of day are presented. Spectra of the indicated processes were investigated and their approximation models were also built. Previously assumed statistical relationships between space-geophysical processes and Caspian Sea level(CSL) changes were confirmed. A close connection was revealed between the low-frequency models of the solar and geomagnetic activity parameters and the CSL changes. Predictions extending into the next decades showed a high probability of an increase in the CSL and a decrease of the compared space-geophysical parameters. 展开更多
关键词 CSL Analysis of sea level changes in the Caspian Sea related to Cosmo-geophysical processes based on satellite and terrestrial data LOD SSN
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Fast Web - Based Data Transmission 被引量:2
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作者 Wei Zukuan Department of Computer Science & Engineering, Inha University, Inchon 402 751, Korea Kim Jaehong Department of Computer Science, Youngdong University, Youngdong, Korea Bae Haeyoung Department of Computer Science & Engineering, Inha Uni 《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期165-176,共12页
Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient metho... Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient methods for this purpose: division transmission and progressive transmission methods. In division transmission method, a map can be divided into several parts, called “tiles”, and only tiles can be transmitted at the request of a client. In progressive transmission method, a map can be split into several phase views based on the significance of vertices, and a server produces a target object and then transmits it progressively when this spatial object is requested from a client. In order to achieve these methods, the algorithms, “tile division”, “priority order estimation” and the strategies for data transmission are proposed in this paper, respectively. Compared with such traditional methods as “map total transmission” and “layer transmission”, the web based GIS data transmission, proposed in this paper, is advantageous in the increase of the data transmission efficiency by a great margin. 展开更多
关键词 spatial data transmission spatial query processing web based GIS geographic information system spatial database.
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COATED CARBIDE TOOL'S CUTTING PERFORMANCE AND ITS DATA BASE
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作者 Zhou Qu Zhou Lanying Yu Qixun(Beijing institute of Technology) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1995年第3期203-208,共17页
The development and application of coated cemented carbide made in China are pres-ented. Three aspects of the coated carbide tool's performance: cutting forces, surface finish and toollife are studied. Furthermore... The development and application of coated cemented carbide made in China are pres-ented. Three aspects of the coated carbide tool's performance: cutting forces, surface finish and toollife are studied. Furthermore speed-correcting coefficients of the tool are given. On the basis of thework, a data base for coated carbide tools has been built on a microcomputer. It consists of fivemodules. essential data base, tools' comparison and inquiry, recommending cutting regimes, exper.imental curve base and an expert system for tool selection. 展开更多
关键词 Coated carbide Cutting performance data base
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数据采集系统实验教学设计与实践
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作者 刘兴茂 张绍全 +1 位作者 庄慧敏 靳小钊 《电气电子教学学报》 2024年第4期208-211,共4页
“电气测量技术”课程传统实验教学在一定程度上忽视了培养学生分析、解决问题的能力。因此,以“数据采集系统”为项目主题,设计了驱动问题、学习目标以及评价方案;在项目实施中,应用开源软件和硬件搭建项目“脚手架”,融入设计思维理念... “电气测量技术”课程传统实验教学在一定程度上忽视了培养学生分析、解决问题的能力。因此,以“数据采集系统”为项目主题,设计了驱动问题、学习目标以及评价方案;在项目实施中,应用开源软件和硬件搭建项目“脚手架”,融入设计思维理念,从而构建了基于项目式学习与设计思维的实验教学模式。实践结果表明:该教学模式有助于激发学生对课程实验的兴趣以及提升学生的工程实践能力。 展开更多
关键词 数据采集系统 项目式学习 设计思维
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基于置信规则库气象站故障检测专家系统
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作者 陈晓 嵇伟明 张凯 《信息技术》 2024年第9期161-167,共7页
针对气象站故障检测的需求,研制了基于置信规则库的气象站故障检测专家系统。专家系统利用前期建立起来的气象站的气象数据库,根据当前实时气象数据,通过改进的置信规则库模型结合专家经验知识自动完成数据分析和处理、是否有故障判断... 针对气象站故障检测的需求,研制了基于置信规则库的气象站故障检测专家系统。专家系统利用前期建立起来的气象站的气象数据库,根据当前实时气象数据,通过改进的置信规则库模型结合专家经验知识自动完成数据分析和处理、是否有故障判断并对故障程度进行等级划分。工作人员在进行现场故障检测之前,只需通过气象站传感器故障专家系统对异常传感器进行辅助诊断,确定故障等级后依据故障等级携带相应检修设备或需更换的零部件进入现场实施检查和维修。实验测试表明系统对各个设备的总体平均检测准确率从69.8%提高到85.7%,极大提升了检测的效率和准确性。 展开更多
关键词 气象站 故障检测 置信规则库 专家系统 数据分析
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结合区块链和关系数据库管理的会计信息系统安全方案
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作者 赵丽 刘光柱 《贵阳学院学报(自然科学版)》 2024年第3期51-56,共6页
会计信息系统(AIS)是企业资源规划(ERP)的核心模块,过去一直被设计为集中式系统,存在单点故障、可扩展性、安全性、灵活性等方面的缺陷。为此,提出了结合联盟区块链和关系数据库管理系统(RDMBS),支持事务防篡改和签名验证的分布式AIS系... 会计信息系统(AIS)是企业资源规划(ERP)的核心模块,过去一直被设计为集中式系统,存在单点故障、可扩展性、安全性、灵活性等方面的缺陷。为此,提出了结合联盟区块链和关系数据库管理系统(RDMBS),支持事务防篡改和签名验证的分布式AIS系统。通过将区块链嵌入关系表中,在数据库中以防篡改的方式存储可信信息,并支持数据的溯源和验证。整个系统由多个经授权的参与方共同维护,支持AIS数据的安全整合,并通过签名方案明确数据所有权。为支持大规模查询,应用了基于动态布隆过滤树(DBFT)的优化算法,以最大限度降低查询和验证作业的总时间成本。实验评估表明,所提方法在AIS系统中成功实现了基于区块链的身份验证和篡改溯源,并显著提升了大规模分析查询和验证的效率。 展开更多
关键词 会计信息系统 联盟区块链 企业资源规划 关系数据库管理系统 动态布隆过滤树
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气象雷达数据管理和个例资料整编设计
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作者 邹红 青娉楚 卢淞岩 《科技资讯》 2024年第3期29-32,共4页
雷达气象资料是短临预报、灾害天气预警的重要资料。气象雷达数据管理和个例资料整编系统采用WinForm编程语言和MSSQLServer2008数据库开发技术建立了相应的南充雷达气象资料数据库。同时,系统可以有效实现基数据、产品数据、历史个例... 雷达气象资料是短临预报、灾害天气预警的重要资料。气象雷达数据管理和个例资料整编系统采用WinForm编程语言和MSSQLServer2008数据库开发技术建立了相应的南充雷达气象资料数据库。同时,系统可以有效实现基数据、产品数据、历史个例资料等气象雷达数据的整编、压缩、入库、查询、统计、下载等功能,减少人为操作,提高业务工作效率。同时为各级气象业务人员下载雷达资料和查询历史个例信息提供了便利,并能够满足业务应用中对雷达气象资料存储和检索的要求,达到了对台站雷达资料高效管理的目的。 展开更多
关键词 基数据 产品数据 历史个例 整编 系统设计
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占空比传输机制下基于协同预测的时变不确定系统递推滤波
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作者 高宏宇 余林栋 +2 位作者 胡银鸽 李悦 侯男 《化工自动化及仪表》 CAS 2024年第2期227-236,共10页
以工业互联网为背景,研究占空比传输机制下一类时变不确定系统的滤波问题,结合协同预测方法设计了新颖的递推滤波算法,解决了占空比传输机制下滤波性能降低的问题。首先给出描述占空比传输机制的数学模型,然后提出结合协同预测方法的递... 以工业互联网为背景,研究占空比传输机制下一类时变不确定系统的滤波问题,结合协同预测方法设计了新颖的递推滤波算法,解决了占空比传输机制下滤波性能降低的问题。首先给出描述占空比传输机制的数学模型,然后提出结合协同预测方法的递推滤波方案,设计基于占空比机制的递推滤波算法,推导了滤波误差协方差矩阵的一个上界,随后分析这个上界的有界性,实现了在稀疏数据情形下提高滤波性能的目的。仿真结果验证了所提算法的高效性和有效性。 展开更多
关键词 递推滤波 传输机制 占空比 协同预测 时变不确定系统 稀疏数据 基于项目的算法
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