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地理环境因子对民航飞行“接地距离远”超限事件影响分析
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作者 冉瑾瑜 孙华波 刘岳峰 《航空工程进展》 CSCD 2024年第3期81-89,共9页
“15 m(50 ft)至接地距离远”是民航客机在着陆阶段常发生的超限事件。研究机场地理环境因子对该超限事件的影响,能够为机场选址和飞行品质评估提供参考依据。使用飞机快速存储记录器(QAR)数据、机场的地形和气象数据,通过全局和局部相... “15 m(50 ft)至接地距离远”是民航客机在着陆阶段常发生的超限事件。研究机场地理环境因子对该超限事件的影响,能够为机场选址和飞行品质评估提供参考依据。使用飞机快速存储记录器(QAR)数据、机场的地形和气象数据,通过全局和局部相关性分析,确定“接地距离远”事件的主要地理环境影响因子;基于地理加权回归模型,建立“接地距离远”事件频率与高程、起伏度以及气温之间的回归模型;根据回归系数,采用Kmeans聚类算法将因子的影响模式分为五类,探究地理环境因子对“接地距离远”事件影响的空间格局及作用机制。结果表明:“接地距离远”事件频率与高程、起伏度、气压和气温有显著的相关性,各因子对“接地距离远”事件的影响强度和方向存在明显的空间分异现象,同一影响模式下的机场在空间分布上呈现出聚集性。 展开更多
关键词 飞行品质监控 接地距离远事件 快速存储记录器 地理环境因子 地理加权回归
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浅谈如何防止落地过程中平飘距离远
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作者 吴世杰 《科技传播》 2010年第22期47-47,共1页
本文就如何防止落地过程中平飘距离远问题的一个细节做浅尝辄止,望能抛砖引玉,引起大家更多的讨论与思考。
关键词 飞行员 落地平飘距离远 危害和成因
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文章应有“距离”
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作者 牛书培 《新闻爱好者》 1996年第1期26-26,共1页
在一次新闻培训班上,人民日报社王黎江先生曾对我说,写文章要注意与人家文章的距离远一点。此话说得有点含蓄,但意思很明白,那就是写文章选题应忌随人后,要力求出新,写人未写或没有写透的问题。
关键词 人民日报社 写文章 距离远 培训班 白点 文人 新闻 选题 祝文 口凹
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In- and Anti-transition of Firing Patterns Induced by Random Long-range Connections in Coupled Hindmarsh-Rose Neurons System 被引量:1
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作者 王鹏 张季谦 任海林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期23-29,I0001,共8页
The effects of random long-range connections (shortcuts) on the transitions of neural firing patterns in coupled Hindmarsh-Rose neurons are investigated, where each neuron is subjected to an external current. It is ... The effects of random long-range connections (shortcuts) on the transitions of neural firing patterns in coupled Hindmarsh-Rose neurons are investigated, where each neuron is subjected to an external current. It is found that, on one hand, the system can achieve the transition of neural firing patterns from the fewer-period state to the multi-period one, when the number of the added shortcuts in the neural network is greater than a threshold value, indicating the occurrence of in-transition of neural firing patterns. On the other hand, for a stronger coupling strength, we can also find the similar but reverse results by adding some proper random connections. In addition, the influences of system size and coupling strength on such transition behavior, as well as the internality between the transition degree of firing patterns and its critical characteristics for different external stimulation current, are also discussed. 展开更多
关键词 In- and anti-transition Random long-range connection Firing pattern System size
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智能无线自组网络高压输电线路故障预警及定位系统研究 被引量:4
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作者 任廷华 陶国 蒋红军 《电力设备管理》 2020年第1期136-138,共3页
根据高压输电线路的布局和监测参数特点设计并实现了一种多节点多层次的拓扑传感网络,具有可靠性高、安全性高、运行费用低等特点,尤其适合偏远无手机信号地区的高压输电线路在线实时监测。
关键词 无线自组数据传输网络 微功率无线技术 距离远功率低 低成本
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新型数字式光学锥体测量传感器设计与实现
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作者 陈佳璧 吴慧 韩秋楠 《中国测试》 CAS 北大核心 2022年第S01期135-142,共8页
为进一步优化直升机旋翼系统运行状态在线监测设备,设计了一种测试精度高、作用距离远、体积小、质量轻的新型数字式光学锥体测量传感器,将前端光电探测传感器与后端采集处理系统集成于一体,使模块化机载锥体测量成为可能。该传感器基于... 为进一步优化直升机旋翼系统运行状态在线监测设备,设计了一种测试精度高、作用距离远、体积小、质量轻的新型数字式光学锥体测量传感器,将前端光电探测传感器与后端采集处理系统集成于一体,使模块化机载锥体测量成为可能。该传感器基于ARM平台,重点研究了微弱光信号转换及处理技术,采用了特殊的光路设计,解决了机载条件下的环境适应性问题,并建立了多机型检验验证方法,实现了直升机旋翼系统运行状态的在线监测,试验结果表明该传感器与原有测量设备相比质量减小为原来的四分之一,技术达到了国际先进水平。 展开更多
关键词 机载 非接触 数字式 锥体测量 微弱光信号 作用距离远
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Analysis of a Wenzhou-Hitting Exceptionally Strong Rainstorm Associated with a Typhoon Inverted Trough in September,1999
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作者 郑峰 《Marine Science Bulletin》 CAS 2010年第1期39-47,共9页
Using T106 numerical products, MM5 simulations in conjunction of Q-vector scheme-computed NCEP results, observations and satellite cloud images, study is undertaken for an exceptionally intense rainstorm event afflict... Using T106 numerical products, MM5 simulations in conjunction of Q-vector scheme-computed NCEP results, observations and satellite cloud images, study is undertaken for an exceptionally intense rainstorm event afflicting the Wenzhou region of Zhejiang province far away from the tropical storm center happening early on the morning of September 4, 1999 (TS9909 hereinafter). Evidence suggests that, like previously-studied typhoons landing in autumn south of Xiamen to the eastern part of Guangdong, TS9909 has an inverted trough in the central south of the coastal belt of Zhejiang province that produces the rainstorm from the meso convective complex (MCC) on the warm, moist shear inside; the time and order of the magnitude of the rainfall are bound up with the development of the pattern of strong Q-vector divergence gradients during the event for the study area; the NE - SW coastline and the unique topography of the Yandang mountains inside the region are favorable for air lifting are the major contributors to the torrential rains. 展开更多
关键词 long-distance-away typhoon rainstorm inverted trough MCC Q-vector divergence gradient
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行车中的错觉
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作者 彭文刚 《道路交通管理》 2000年第4期10-10,共1页
关键词 驾驶员 距离远 曲率半径 跟车距离 曲线半径 色错觉 感知觉 远光灯 注意力 加油门
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袖珍型窃听器探测器
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作者 王耀松 《警察技术》 1996年第4期24-24,共1页
袖珍型窃听器探测器Transtec袖珍型射频发射探测器已经由TorfinoEnterprises引进。它把射频发射探测器功能、发射监视功能和射频扫描设备组合成一整体。作为探测器使用时,它提供两个信号告诉使用者存在射频... 袖珍型窃听器探测器Transtec袖珍型射频发射探测器已经由TorfinoEnterprises引进。它把射频发射探测器功能、发射监视功能和射频扫描设备组合成一整体。作为探测器使用时,它提供两个信号告诉使用者存在射频发射机。它可隐匿在身体上,如果探测... 展开更多
关键词 袖珍型 探测器 射频发射 听器 射频扫描 设备组合 调节控制 距离远 使用者 敏度
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In-situ measurement of CO2 at the Xinglong regional background station over North China 被引量:3
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作者 YANG Yang WANG Ting +2 位作者 WANG Pucai ZHOU Minqiang YAO Bo 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第6期385-391,共7页
High-accuracy continuous measurements of atmospheric concentrations of CO2 were made from May 2016 to December 2017 using the Picarro G2301 analyzer at Xinglong station(40°24′N,117°30′E,940 MSL),150 km nor... High-accuracy continuous measurements of atmospheric concentrations of CO2 were made from May 2016 to December 2017 using the Picarro G2301 analyzer at Xinglong station(40°24′N,117°30′E,940 MSL),150 km northeast of Beijing.The near-ground CO2 measurements were calibrated by standards based on WMO procedures.The regional background measurements were ltered by the robust extraction of baseline signal method to study the seasonal and diurnal cycles.The regional background CO2 concentrations were low in summer.The maximum diffierence between the local sources and regional background CO2 concentrations occurred in summer and autumn,indicating a strong in uence from local sources.Cluster analysis and potential source contribution function analysis showed that the long-distance transport of anthropogenic emissions in the Beijing Tianjin Hebei metropolitan area in uenced the CO2 concentrations in Xinglong,espe-cially in summer.The diurnal variation of CO2 was mainly in uenced by the various vertical transport conditions of the tropospheric atmosphere in a day. 展开更多
关键词 Xinglong station CO2 concentration VARIATION source analysis
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A Real-Time System for Monitoring Distant Dynamic Displacement of Structures 被引量:4
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作者 CHEN Junfeng ZHAO Wenguang +2 位作者 LUO Hongbin LI Penghui WEN Yinping 《Geo-Spatial Information Science》 2008年第1期49-55,共7页
Based on digital image processing technique, a real-time system is developed to monitor and detect the dynamic displacement of engineering structures. By processing pictures with a self-programmed software, the real-t... Based on digital image processing technique, a real-time system is developed to monitor and detect the dynamic displacement of engineering structures. By processing pictures with a self-programmed software, the real-time coordinate of an object in a certain coordinate system can be obtained, and further dynamic displacement data and curve of the object can also be achieved. That is, automatic gathering and real-time processing of data can be carried out by this system simultaneously. For this system, first, an untouched monitoring technique is adopted, which can monitor or detect objects several to hundreds of meters apart; second, it has flexible installation condition and good monitoring precision of sub-millimeter degree; third, it is fit for dynamic, quasi-dynamic and static monitoring of large engineering structures. Through several tests and applications in large bridges, good reliability and dominance of the system is proved. 展开更多
关键词 dynamic displacement real-time monitoring and detecting SUB-PIXEL system calibration dynamic tracking
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Teleportation of an Arbitrary Three-Particle State via Three EPR Pairs 被引量:8
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作者 FANGJian-Xing ZHUShi-Qun CHENXian-Feng ZHANGRong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期369-372,共4页
A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the origi... A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the original state with deterministic probability can be reconstructed by the receiver when a corresponding unitary transformation is followed. 展开更多
关键词 TELEPORTATION arbitrary three-particle state three-entangled particle pairs unitary transformation
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Study of Remote Monitoring and Maintenance Guiding Technique Based on LabVIEW for Machining Centers 被引量:2
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作者 JIA Zhi-cheng HU Zhong-xiang SHI Xiao-jun 《Journal of Donghua University(English Edition)》 EI CAS 2005年第5期29-33,共5页
The virtual instruments (VIs), as a new type of instrument based on computer, has many advanced attractive characteristics. This research is based on Vls, and brings condition monitoring and knowledge-based maintena... The virtual instruments (VIs), as a new type of instrument based on computer, has many advanced attractive characteristics. This research is based on Vls, and brings condition monitoring and knowledge-based maintenance support together through an integrated (including hate.met, ASP. NET, XML tochnique, Vls) network environme~. Within the enviromnent, machining centers operators, engineers or managers can share real-time data through the browser-based interface and minimize machining centers downtime by providing status monitoring and remote maintenance guiding from service centers. 展开更多
关键词 remote monitoring machining center maintenance guiding LABVIEW XML ASP. NET
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Neural Network Based on Rough Sets and Its Application to Remote Sensing Image Classification 被引量:3
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作者 WUZhaocong LIDeren 《Geo-Spatial Information Science》 2002年第2期17-21,共5页
This paper presents a new kind of back propagation neural network (BPNN) based on rough sets,called rough back propagation neural network (RBPNN).The architecture and training method of RBPNN are presented and the sur... This paper presents a new kind of back propagation neural network (BPNN) based on rough sets,called rough back propagation neural network (RBPNN).The architecture and training method of RBPNN are presented and the survey and analysis of RBPNN for the classification of remote sensing multi_spectral image is discussed.The successful application of RBPNN to a land cover classification illustrates the simple computation and high accuracy of the new neural network and the flexibility and practicality of this new approach. 展开更多
关键词 rough sets back propagation neural network remote sensing image classification
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Matlab/Simulink Based Dynamic Simulation System for Distance Protection 被引量:1
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作者 许明 高厚磊 闫超 《Transactions of Tianjin University》 EI CAS 2008年第2期112-117,共6页
To observe the inner operating process of distance protection,a Matlab/Simulink based dynamic simulation system for microprocessor-based distance protection is designed in this paper.As a modularized design,the simula... To observe the inner operating process of distance protection,a Matlab/Simulink based dynamic simulation system for microprocessor-based distance protection is designed in this paper.As a modularized design,the simulation system is composed of several modules such as fault transient calculation,startup,Fourier algorithm,phase selection,impedance computing and impedance comparison etc.Some typical simulation cases,which focus on the main factors affecting distance relay's operation,have been simulated with the system.Simulation results show that the system is able to demonstrate the dynamic behaviors of distance protection under different operating conditions. 展开更多
关键词 distance protection dynamic simulation Matlab/Simulink impedance trace
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Teleportation of Two-Mode Quantum State of Continuous Variables 被引量:1
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作者 SONGTong-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期362-364,共3页
Using two Einstein-Podolsky Rosen pair eigenstates |η) as quantum channels, we study the teleportationof two-mode quantum state of continuous variables.
关键词 TELEPORTATION EPR pair eigenstate generalized two-mode squeezed vacuum
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INTERANNUAL VARIATION CHARACTERISTICS OF EAST HEMISPHERIC CROSS-EQUATORIAL FLOW AND ITS CONCURRENT RELATIONSHIPS WITH TEMPERATURE AND RAINFALL IN CHINA
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作者 雷小春 杨修群 《Journal of Tropical Meteorology》 SCIE 2008年第2期97-100,共4页
The NCEP/NCAR global reanalysis data were used to analyze the interannual variation characteristics of the cross-equatorial flow (CEF) and its concurrent relationships with temperature and rainfall in China. The resul... The NCEP/NCAR global reanalysis data were used to analyze the interannual variation characteristics of the cross-equatorial flow (CEF) and its concurrent relationships with temperature and rainfall in China. The results indicated that CEF changes more in summer than in winter. As the main flow channel in summer, the Somali CEF changes in a way that does not markedly influence the changes in the CEF total except for winter. The summer CEF total has two sudden increases and one sudden decrease during the last century while the winter total has just one decrease. Long-period data show that the correlation between CEF and summer rainfall in China is not very significant, but is different before and after the 1970s, which is due to CEF's close links with the East Asia summer monsoon. Winter CEF's correlation with concurrent winter temperature in northern and southern China varies with the relationship between CEF and sea-level pressure in different areas. 展开更多
关键词 cross-equatorial flow (CEF) interannual variation characteristics RAINFALL TEMPERATURE correlation
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PREVIOUS CONVECTION ANOMALY IN AUTUMN AND WINTER ASSOCIATED WITH THE GENERAL CIRCULATION OVER EAST ASIA IN WINTER AND SPRING AND APRIL PRECIPITATION IN SHANDONG
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作者 胡桂芳 张璇 顾伟宗 《Journal of Tropical Meteorology》 SCIE 2008年第2期133-136,共4页
Using OLR and 850 hPa and 200 hPa wind fields data (1979 - 2006), this paper diagnoses the characteristics of convection over the tropical area in preceding autumns and winters in association with April precipitation ... Using OLR and 850 hPa and 200 hPa wind fields data (1979 - 2006), this paper diagnoses the characteristics of convection over the tropical area in preceding autumns and winters in association with April precipitation anomalies in Shandong province. It is found that preceding convection anomalies over the Western Pacific Warm Pool in December have close relationships with the April precipitation in Shandong. Further analysis of the relationship with the general circulation over the East Asia shows that the convection anomaly over the Western Pacific Warm Pool has close relationships with the Main East Asian Trough, the Hadley cell over East Asia and the Walker cell. The characteristics of East Asian atmospheric circulation anomalies accompanied with stronger (weaker) convection are consistent with those of less (more) April precipitation anomalies in Shandong. Therefore, the convection anomaly over the tropics in December may be an important indicator for April precipitation in Shandong. 展开更多
关键词 convection over the tropics general circulation over East Asia April precipitation in Shandong
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Development of Virtual Account System for Research Projects Based on J2EE
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作者 张利 曾献辉 +1 位作者 邵世煌 罗丽丽 《Journal of Donghua University(English Edition)》 EI CAS 2006年第1期8-11,共4页
Based on the analysis of developing target, function and constitution of research projects system for remote management, the virtual account system is established on 3 layers of B/S mode. The development process of vi... Based on the analysis of developing target, function and constitution of research projects system for remote management, the virtual account system is established on 3 layers of B/S mode. The development process of virtual account system is realized by JSP/Servlets development language and MySQL database under windows server 2003 platform. At the same time, network security module of the system has been realized to reduce the influence caused by network security incidents. The system is capable of updating the information of vertical and horizontal projects dynamically and assigning virtual funds on WWW. Also, it realizes the query, statistical analysis function and so on. Practical results show that the system is a successful system for analyzing the various projects index of different departments. 展开更多
关键词 virtual account remote management JSP/servlets network security.
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Teleportation of Multi-ionic GHZ States and Arbitrary Bipartite Ionic State via Linear Optics
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作者 ZHOU Jian DONG Ping CAO Zhuo-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期847-850,共4页
We present a scheme for teleportation of multi-ionic GHZ states and arbitrary bipartite ionic state only by single-qubit measurements via linear optical elements. In our scheme, we avoid the difficulty of joint measur... We present a scheme for teleportation of multi-ionic GHZ states and arbitrary bipartite ionic state only by single-qubit measurements via linear optical elements. In our scheme, we avoid the difficulty of joint measurement and synchronizing the arrival time of the two scattered photons, which are faced by previous schemes. So our scheme can be realized easily within current experimental technology. 展开更多
关键词 GHZ state TELEPORTATION linear optics
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