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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:42
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 multi - site cardiac pacingHemodynamics
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Research on A Master - slave Multi - microcomputers Control System for Hollow Spindle Fancy Yarn Spinning Machine
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作者 李志蜂 陈子展 阵瑞琪 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期49-52,共4页
In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardwar... In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology. 展开更多
关键词 hollow SPINDLE FANCY YAM spinning machine mechatrvnical fusion MASTER - SLAVE multi - microcomputers control system PC - BUS.
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On the Representation of Multi-layer Woven Structure
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作者 易洪雷 丁辛 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期14-16,共3页
A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the rein... A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed. 展开更多
关键词 multi - layer woven FABRIC structural parame-ter BINDING PATTERN TEXTILE composite .
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Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics
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作者 李炜 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期85-87,共3页
To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the ... To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory. 展开更多
关键词 multi - bar WARP KNITTED fabric computer -aided PATTERN design PATTERN Object Windows class Library (OWL) programming.
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MODS: A Novel Metaheuristic of Deterministic Swapping for the Multi-Objective Optimization of Combinatorials Problems
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作者 Elias David Nifio Ruiz Carlos Julio Ardila Hemandez +2 位作者 Daladier Jabba Molinares Agustin Barrios Sarmiento Yezid Donoso Meisel 《Computer Technology and Application》 2011年第4期280-292,共13页
This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Auto... This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Automata (MDFA) is defined. MDFA allows the representation of the feasible solutions space of combinatorial problems. Second, it is defined and implemented a metaheuritic based on MDFA theory. It is named Metaheuristic of Deterministic Swapping (MODS). MODS is a local search strategy that works using a MDFA. Due to this, MODS never take into account unfeasible solutions. Hence, it is not necessary to verify the problem constraints for a new solution found. Lastly, MODS is tested using well know instances of the Bi-Objective Traveling Salesman Problem (TSP) from TSPLIB. Its results were compared with eight Ant Colony inspired algorithms and two Genetic algorithms taken from the specialized literature. The comparison was made using metrics such as Spacing, Generational Distance, Inverse Generational Distance and No-Dominated Generation Vectors. In every case, the MODS results on the metrics were always better and in some of those cases, the superiority was 100%. 展开更多
关键词 METAHEURISTIC deterministic finite automata combinatorial problem multi - objective optimization metrics.
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DL/T645-2007《多功能电能表通信协议》的技术特点和创新 被引量:21
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作者 马利人 宗建华 《电测与仪表》 北大核心 2009年第3期1-3,13,共4页
介绍了DL/T 645-2007《多功能电能表通信协议》制订中考虑的主要问题,以及《多功能电能表通信协议》各部分主要变化和技术创新,同时讨论了兼容问题的对策。
关键词 多功能电能表 负荷记录 帧序号 数据冻结 通信地址
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HFC上行信道S-CDMA接入的多用户检测
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作者 郑勇 周正华 朱维乐 《电子科技大学学报》 EI CAS CSCD 北大核心 2001年第3期221-225,235,共6页
分析了 HFC上行信道的特点,提出使用S-CDMA技术可以在极低的信噪比下获得稳固的传输特性。讨论了多种检测接收方案,并将解相关判决反馈多用户检测算法应用于HFC上行信道S-CDMA系统的接收,利用消除强功率信号的干... 分析了 HFC上行信道的特点,提出使用S-CDMA技术可以在极低的信噪比下获得稳固的传输特性。讨论了多种检测接收方案,并将解相关判决反馈多用户检测算法应用于HFC上行信道S-CDMA系统的接收,利用消除强功率信号的干扰达到弱功率信号的正确判决,达到有效地消除多址干扰和抗远近效应目的。其算法的复杂性与用户数成正比,每个用户只需作一次判决。系统不需要精确的同步和功率控制,从而简化了系统。 展开更多
关键词 混合光纤同轴网 同步码分多址 通信网 上行信道 多用户检测 有线电视网
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基于频分的MC-CDMA多用户系统
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作者 杨灵 莫滔 张蕴玉 《电子科技》 2007年第1期27-30,共4页
对多载波码分多址系统的多用户接收进行了研究,提出了基于频分的多载波码分多址(FD—MC—CDMA)系统,它是在MC—CDMA基础上结合FDMA的思想,发射端为每个用户分配一个特定的子载波集进行数据传输,减少相同子栽波上所叠加用户的数目;接收... 对多载波码分多址系统的多用户接收进行了研究,提出了基于频分的多载波码分多址(FD—MC—CDMA)系统,它是在MC—CDMA基础上结合FDMA的思想,发射端为每个用户分配一个特定的子载波集进行数据传输,减少相同子栽波上所叠加用户的数目;接收端使用最大似然检测器,利用所有接收信号进行多用户联合检测。该系统与传统的MC-CDMA系统相比有保证频率分集增益的同时降低多址干扰、有效利用多用户信息的优点。经过在Matlab平台上的仿真,结果表明,在频率选择性衰落信道和相同接入用户数的情况下,该系统与传统的MC—CDMA系统相比拥有更低的误码率,并且误码率随着用户数的增加呈阶梯状的缓慢递增。 展开更多
关键词 多载波码分多址 多址干扰 多用户检测 最大似然检测器
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DS-CDMA系统多波形优化的多址干扰抑制方法
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作者 李清伟 郭黎利 《西安交通大学学报》 EI CAS CSCD 北大核心 2017年第10期94-99,106,共7页
针对异步直扩-码分多址(DS-CDMA)系统多址干扰引起误码率性能降低的问题,提出了DS-CDMA系统多波形优化的多址干扰抑制方法。首先,从常规波形中选取所有q(q≥3)种波形组合,通过q种波形能量谱的平均分别计算每种组合的等效波形能量谱;然后... 针对异步直扩-码分多址(DS-CDMA)系统多址干扰引起误码率性能降低的问题,提出了DS-CDMA系统多波形优化的多址干扰抑制方法。首先,从常规波形中选取所有q(q≥3)种波形组合,通过q种波形能量谱的平均分别计算每种组合的等效波形能量谱;然后,引入能量谱平坦度量化计算每种组合的等效波形能量谱平坦度;最后,优化选取平坦度大的波形组合,并循环使用这些优化波形组合与扩频序列进行扩频信号的构造,同时,CDMA用户在发射端使用构造的扩频信号扩频并在接收端使用同样的扩频信号进行解扩。仿真结果表明:与双波形方法相比,多波形优化方法能够有效抑制用户间的多址干扰,使多址干扰下的CDMA用户误码率性能提升2dB。 展开更多
关键词 DS-CDMA系统 多波形 多址干扰 误码率
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TD-SCDMA系统小区内干扰分析
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作者 王安义 郭伟 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2008年第5期734-737,共4页
为了研究并分析第三代移动通信TD-SCDMA系统小区内的干扰,奠定TD-SCDMA系统的容量、覆盖等基本性能指标的重要理论基础,在给出单载波小区干扰模型条件下,通过对单载波TD-SCDMA系统小区内符号间的干扰和多址干扰进行定性地研究与分析,给... 为了研究并分析第三代移动通信TD-SCDMA系统小区内的干扰,奠定TD-SCDMA系统的容量、覆盖等基本性能指标的重要理论基础,在给出单载波小区干扰模型条件下,通过对单载波TD-SCDMA系统小区内符号间的干扰和多址干扰进行定性地研究与分析,给出了干扰的分析和计算方法,分析了智能天线和联合检测技术对TD-SCDMA系统干扰的影响,并通过实际组网条件下TD-SCDMA系统内的干扰进行了计算机仿真结果和分析,验证了对TD-SCDMA系统中对小区内干扰的研究与分析结论,从而得到了影响系统的容量、覆盖等基本性能指标重要的理论依据。 展开更多
关键词 TD-SCDMA 多址干扰MAI 无线资源管理
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采用2D-SMPC码的S-OCDMA系统性能分析
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作者 张晓燕 杨祎 《计算机工程与应用》 CSCD 北大核心 2010年第26期86-88,共3页
在同步修正素数码(SMPC)基础上,通过给每个不同的种子分配一个不同的波长片,构造了二维正交地址码(2D-SMPC);分析了码字的相关特性,确定了地址码选取原则;通过Optisystem仿真,研究了该码的多址干扰(MAI)和系统容量等性能。与一维SMPC码... 在同步修正素数码(SMPC)基础上,通过给每个不同的种子分配一个不同的波长片,构造了二维正交地址码(2D-SMPC);分析了码字的相关特性,确定了地址码选取原则;通过Optisystem仿真,研究了该码的多址干扰(MAI)和系统容量等性能。与一维SMPC码性能相比较,验证了其用于S-OCDMA系统时的性能改善。 展开更多
关键词 同步码分多址 二维同步修正素数码 系统容量 多址干扰
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基于PIC的MC-CDMA系统多级型多用户检测技术
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作者 吴晓葵 《电子设计工程》 2011年第12期124-126,共3页
为了抑制MAI和远近效应以提高系统的性能,采用多级型多用户检测技术,充分利用各个用户的扩频序列时延幅度和相位信息对各用户进行联合检测,利用前级判决的信息构造所有用户的干扰信号,然后从接收信号抵消掉干扰信号,从总体上提高各用户... 为了抑制MAI和远近效应以提高系统的性能,采用多级型多用户检测技术,充分利用各个用户的扩频序列时延幅度和相位信息对各用户进行联合检测,利用前级判决的信息构造所有用户的干扰信号,然后从接收信号抵消掉干扰信号,从总体上提高各用户的性能。仿真验证表明,PIC的处理延迟小,且在用户增多的情况下误码率大为降低,但随着级数的增加,计算复杂度增大,故实际应用中一般选三级为宜。 展开更多
关键词 多用户检测 多址干扰 并行干扰抵消 误码率
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Pressure Gradient Force,Saffman Lift,and Magnus Lift on the Fiber-like Particle in Fluid 被引量:5
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作者 朱泽飞 林建忠 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期23-27,共5页
Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, S... Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, Saffman lift,pressure gradient force, and then the dynamics modelhave been received. The numerical study of the simpleshear flow past the cylinders shows that the particles ’motion is controlled by the vortex. 展开更多
关键词 multi - phase FLUID FIBER - LIKE PARTICLE FORCE analysis
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WORLD NEWS IN BRIEF(August 1-15, 1989)
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《国际展望》 北大核心 1989年第16期32-32,共1页
The international conference on Kampuchea declded on August 1 in Paris to send a UN fact-finding mission to the country to arrange a peace settlement. The Fatah Movement, the mainstream group in the Palestine Liberati... The international conference on Kampuchea declded on August 1 in Paris to send a UN fact-finding mission to the country to arrange a peace settlement. The Fatah Movement, the mainstream group in the Palestine Liberation Organization (PLO), opened its fifth general congress on August 3 in Tunis. PLO Chairman and President of the State of Palestine Yasser Arafat and Tunisian President Zine E1 Abidine Ben All addressed the opening ceremony. 展开更多
关键词 MAINSTREAM CEREMONY ARRANGE addressed CONGRESS Chairman finding AUGUST 1-15 peace FIFTH
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统一地址库建设方案研究
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作者 刘爽 胡强 《测绘与空间地理信息》 2024年第S01期85-87,90,共4页
以精准到户语义地址为纽带,汇聚融合各政务大数据,为新型智慧城市建设提供鲜活的统一地址库,全面赋能社会治理、城市管理、民生服务等应用。本文从统一地址库的数据结构设计、多源数据标准化处理、地址数据匹配、行业部门数据关联、数... 以精准到户语义地址为纽带,汇聚融合各政务大数据,为新型智慧城市建设提供鲜活的统一地址库,全面赋能社会治理、城市管理、民生服务等应用。本文从统一地址库的数据结构设计、多源数据标准化处理、地址数据匹配、行业部门数据关联、数据更新等方面,进行了初步的探讨。 展开更多
关键词 地址数据 多源融合 标准化 数据匹配 数据关联 增量更新
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多源地图平台的政务专题信息整合共享技术研究
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作者 宋婷婷 《测绘与空间地理信息》 2024年第11期99-102,共4页
推进政务专题数据整合、共享、应用是智慧城市建设的重要举措,当前,各政务部门虽然汇聚了大量含有空间位置的专题信息,但各行业无法提供基于统一空间标准的专题数据进行共享使用与联动更新,如何使行业专题数据能够基于统一的空间地理位... 推进政务专题数据整合、共享、应用是智慧城市建设的重要举措,当前,各政务部门虽然汇聚了大量含有空间位置的专题信息,但各行业无法提供基于统一空间标准的专题数据进行共享使用与联动更新,如何使行业专题数据能够基于统一的空间地理位置进行整合匹配成为解决问题的关键。因此,本文以山东省政务专题数据为例,提出通过“汇聚库、匹配库,成果库”作为数据整合的流程底座,以多源在线地图平台的地理编码服务和地名检索服务作为专题数据整合的关键技术支撑,推进了专题数据跨部门整合共享,提升了政务服务效能。 展开更多
关键词 专题数据 整合共享 多源地图平台 地名地址匹配
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扩频通信在煤矿井下通信和安全中的应用 被引量:10
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作者 吴明捷 张克 张威 《煤炭学报》 EI CAS CSCD 北大核心 2002年第1期88-91,共4页
总结了我国煤矿通信 ,尤其是井下通信多年存在的问题 ,指出扩频通信的抗干扰能力强 ,易于实现码分多址 ,能够做到模拟信号和数字信号兼容等优点 ,特别适合煤矿通信 ,因此引进扩频通信新技术 ,能够推动煤矿通信的发展 ,达到现代化的要求 ... 总结了我国煤矿通信 ,尤其是井下通信多年存在的问题 ,指出扩频通信的抗干扰能力强 ,易于实现码分多址 ,能够做到模拟信号和数字信号兼容等优点 ,特别适合煤矿通信 ,因此引进扩频通信新技术 ,能够推动煤矿通信的发展 ,达到现代化的要求 .论述了扩频通信技术在煤矿中实现移动通信的应用前景 ,指出可行的具体方案 :在主巷道使用漏泄电缆 ,而在其它巷道采用中频感应扩频通信 。 展开更多
关键词 扩频通信 移动通信 码分多址 CDMA 安全 矿井 煤矿 抗干扰能力
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基于随机多址协议的系统吞吐量分析 被引量:15
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作者 佘明辉 赵东风 《吉林大学学报(信息科学版)》 CAS 2010年第1期13-19,共7页
为解决当多个用户通过一个公共信道与其他用户进行通信时必须采用多址技术的问题。在详细阐述了时隙ALOHA系统和连续时间ALOHA系统以及非坚持CSMA(Carrier Sense Multiple Access)控制协议的分析的同时,分别得出了3种系统的平均成功队... 为解决当多个用户通过一个公共信道与其他用户进行通信时必须采用多址技术的问题。在详细阐述了时隙ALOHA系统和连续时间ALOHA系统以及非坚持CSMA(Carrier Sense Multiple Access)控制协议的分析的同时,分别得出了3种系统的平均成功队长和系统吞吐量的数学表达式,并通过仿真实验验证了理论分析的正确性。 展开更多
关键词 随机多址 信道 循环体 平均周期 吞吐量
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