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具有时滞效应的air2stream河流水温模型及应用研究
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作者 李凌波 王启明 +3 位作者 赵忠伟 唐玉川 李成明 胡艳 《水文》 CSCD 北大核心 2024年第4期45-51,共7页
高精度河流水温模型对于深入了解水温的时空变化特征和河流生态修复具有重要意义。基于数据驱动的air2stream模型在保证预测精度的同时,避免了计算的复杂性,已成为河流水温模拟常用的模型。由于水的热惯性及水文条件等的影响,河流水温... 高精度河流水温模型对于深入了解水温的时空变化特征和河流生态修复具有重要意义。基于数据驱动的air2stream模型在保证预测精度的同时,避免了计算的复杂性,已成为河流水温模拟常用的模型。由于水的热惯性及水文条件等的影响,河流水温变化往往显著滞后于气温变化,而air2stream原模型并未考虑滞后效应,导致该模型在流量未知情况下实际精度偏低。为解决该问题,采用气温-水温皮尔逊相关系数计算时滞天数,构建具有时滞的air2stream新模型,进一步根据长江中下游地区两个监测站的多年实测数据验证新模型的有效性和稳定性。结果表明:新模型在不引进额外观测数据的条件下具有更高精度且性能更稳定。相比原模型,在两个监测站新模型的均方根误差分别降低约4.29%和5.85%。新模型具有精度高、水文要素需求少的特点,可为长江中下游的水环境影响评价和生态保护提供依据。 展开更多
关键词 气温-水温模型 时滞 air2stream 长江中下游水温
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高温环境因素对固-液混合燃料物理稳定性的影响
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作者 张弛 付豪 +2 位作者 宋戈 石睿捷 白春华 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第9期9-16,共8页
固-液混合燃料的物理稳定性对于燃料的质量和安全性均有重要的意义。高温环境引发的易挥发液体组分的气化将对燃料的物理稳定性产生极为复杂的影响。通过自主设计的实验装置模拟、加速燃料物理稳定性改变,并分别从液体燃料析出及密度分... 固-液混合燃料的物理稳定性对于燃料的质量和安全性均有重要的意义。高温环境引发的易挥发液体组分的气化将对燃料的物理稳定性产生极为复杂的影响。通过自主设计的实验装置模拟、加速燃料物理稳定性改变,并分别从液体燃料析出及密度分布变化趋势,分析高温环境因素的作用。结果表明:自然堆垛状态下燃料的顶部受饱和蒸汽压的改变影响较大,而中部、底部则由于燃料的紧密堆积,形成各自独立的气液平衡。同时,液体燃料于高温环境中对固体的润湿效果随之增强,更有利于液体组分完成对固体颗粒的吸附。在303~333 K的温度条件下,固液体积比为1.25∶1,硝基甲烷占液体组分40%的固-液混合燃料保持最佳的物理稳定性。 展开更多
关键词 -液混合燃料 温度因素 物理稳定性 FAE(fuel air explosive)
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基于级联角度的AIRS辅助大规模MIMO系统波束跟踪方案
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作者 马露洁 梁彦 李飞 《系统工程与电子技术》 EI CSCD 北大核心 2024年第7期2515-2524,共10页
智能反射表面(intelligent reflecting surface,IRS)可以通过提供额外的视线(line of sight,LoS)路径补偿传播损耗或解决阻塞问题,有效地提高毫米波(millimeter wave,mmWave)通信系统的性能,被认为是下一代移动通信的核心技术。与传统... 智能反射表面(intelligent reflecting surface,IRS)可以通过提供额外的视线(line of sight,LoS)路径补偿传播损耗或解决阻塞问题,有效地提高毫米波(millimeter wave,mmWave)通信系统的性能,被认为是下一代移动通信的核心技术。与传统的地面IRS相比,部署在无人机、热气球等空中平台上的空中IRS(aerial IRS,AIRS)结合了空中平台的高移动特性/旋转特性和IRS提供的优质链路特性,可以提供更广阔的信号覆盖范围。考虑到现实场景中用户的移动性,通信系统有必要实时调整波束成形以使波束对准移动用户。然而,AIRS不具备有源射频链,难以在AIRS处获取离开角和到达角,增加了波束跟踪的复杂性。针对这一问题,建立了具有时变信道的AIRS辅助mmWave大规模多输入多输出(multiple input multiple output,MIMO)系统模型,结合基站端有源波束成形、AIRS的旋转角度和无源波束成形设计,提出了一种基于级联角度的无迹卡尔曼滤波波束跟踪方案。仿真结果表明,提出的方案具有较高的跟踪精度,同时AIRS的旋转特性对提升系统可达速率起着重要作用。 展开更多
关键词 空中智能反射面 波束成形 波束跟踪 大规模多输入多输出 毫米波
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Reference tracking control for flexible air-breathing hypersonic vehicle with actuator delay and uncertainty 被引量:3
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作者 Hongyi Li Yiming Cheng Yulin Si Huijun Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第1期141-145,共5页
This paper considers the problem of reference tracking control for the flexible air-breathing hypersonic flight vehicle with actuator delay and uncertainty.By constructing the Lyapunov functional including the lower a... This paper considers the problem of reference tracking control for the flexible air-breathing hypersonic flight vehicle with actuator delay and uncertainty.By constructing the Lyapunov functional including the lower and upper bounds of the time-varying delay,the non-fragile controller is designed such that the resulting closed-loop system is asymptotically stable and satisfies a prescribed performance cost index.The simulation results are given to show the effectiveness of the proposed control method,which is validated by excellent output reference altitude and velocity tracking performance. 展开更多
关键词 actuator delay flexible air-breathing hypersonic flight vehicle(FAHFV) non-fragile control output tracking control.
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Three-Dimensional Discrete Observability Analysis for Air-to-Air Missile Target Tracking
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作者 Fei Liu Zhang Ren Yuan Liang 《Journal of Beijing Institute of Technology》 EI CAS 2017年第4期548-556,共9页
The interception information of infrared( IR)-guided air-to-air missiles( AAM) is mainly estimated only using the basic bearing measurements. In order to intercept highly maneuverable targets,it is essential to st... The interception information of infrared( IR)-guided air-to-air missiles( AAM) is mainly estimated only using the basic bearing measurements. In order to intercept highly maneuverable targets,it is essential to study the system observability to improve the target tracking system performance.The uniqueness of this paper is that the observability analysis is derived based on a discrete three-dimensional (3D) system model. During the maneuvering scenario,the system is approximated by a segment-by-segment system. The relationship between missile-target motion and observability is given by direct and dual approaches. Meanwhile sufficient observability conditions are derived. Moreover,a numerical simulation is conducted and an alternate method is provided to reinforce the proposed observability analysis results. 展开更多
关键词 air-to-air missile (AAM) 3D discrete system target tracking observability analysis
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Impacts of Increased SST Resolution on the North Pacific Storm Track in ERA-Interim 被引量:3
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作者 Chao ZHANG Hailong LIU +2 位作者 Jinbo XIE Chongyin LI Pengfei LIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第11期1256-1266,共11页
This study examines the artificial influence of increasing the SST resolution on the storm track over the North Pacific in ERA-Interim.Along with the mesoscale oceanic eddies and fronts resolved during the high-resolu... This study examines the artificial influence of increasing the SST resolution on the storm track over the North Pacific in ERA-Interim.Along with the mesoscale oceanic eddies and fronts resolved during the high-resolution-SST period,the low-level storm track strengthens northward,reaching more than 30%of the maximum values in the low-resolution-SST period after removing the influence of ENSO.The mesoscale structure firstly imprints on the marine atmospheric boundary layer,which then leads to changes in turbulent heat flux and near-surface convergence,forcing a secondary circulation into the free atmosphere,strengthening the vertical eddy heat,momentum and specific humidity fluxes,and contributing to the enhancement of the storm track.Results from a high-resolution atmospheric model further indicate the changes in the storm track due to the mesoscale SST and their relationship. 展开更多
关键词 storm track mesoscale SST air−sea interaction ERA-INTERIM CAM4
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Flight control for a flexible air-breathing hypersonic vehicle based on quasi-continuous high-order sliding mode 被引量:15
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作者 Jie Wang Qun Zong +1 位作者 Bailing Tian Helong Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第2期288-295,共8页
The focus of this paper is on control design and simulation for the longitudinal model of a flexible air-breathing hypersonic vehicle(FAHV).The model of interest includes flexibility effects and intricate couplings ... The focus of this paper is on control design and simulation for the longitudinal model of a flexible air-breathing hypersonic vehicle(FAHV).The model of interest includes flexibility effects and intricate couplings between the engine dynamics and flight dynamics.To overcome the analytical intractability of this model,a nominal control-oriented model is constructed for the purpose of feedback control design in the first place.Secondly,the multi-input multi-output(MIMO) quasi-continuous high-order sliding mode(HOSM) controller is proposed to track step changes in velocity and altitude,which is based on full state feedback.The simulation results are presented to verify the effectiveness of the proposed control strategy. 展开更多
关键词 flexible air-breathing hypersonic vehicle nonlinear robust controller high order sliding mode control output tracking control
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组合称重法与分压法的C_(5)F_(10)O-PFK/Air混气制备技术研究 被引量:3
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作者 朱会 齐汝宾 +3 位作者 曾晓哲 赫树开 吴倩倩 侯新梅 《化学试剂》 CAS 北大核心 2021年第1期89-93,共5页
制备高精度的C5-PFK/Air混合气体有利于实现对C5-PFK气体-电气性能的科学论证。采用称重法与分压法实现了对不同混合比的C5-PFK/Air混合气体的制备,搭建C5-PFK/Air混气制备实验系统,建立了气相色谱-氢火焰离子化检测器(GC-FID)对制备的C... 制备高精度的C5-PFK/Air混合气体有利于实现对C5-PFK气体-电气性能的科学论证。采用称重法与分压法实现了对不同混合比的C5-PFK/Air混合气体的制备,搭建C5-PFK/Air混气制备实验系统,建立了气相色谱-氢火焰离子化检测器(GC-FID)对制备的C5-PFK/Air混气中C5-PFK定性定量分析的仪器方法,可对实验结果进行溯源校准。研究结果表明,制备13%C5-PFK/Air混合气体的RSD为0.89%,最大示值误差为0.77%;压力为0.5 MPa时,12%~15%浓度范围内C5-PFK/Air混气中C5-PFK峰面积线性拟合系数R^(2)为0.995,一致性良好,可完全汽化;6个月的稳定性考察,气体特性值保持不变,稳定性良好。 展开更多
关键词 称重法 分压法 气相色谱-氢火焰离子化检测器 重复性 均匀性 稳定性 C5-PFK/air
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3D Track-keeping Method for Autonomous Underwater Vehicle 被引量:1
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作者 WANG Wei, Bian Xin-Qian, Chang Zong-HuCollege of Power and Nuclear Engineering, Harbin Engineering University, Harbin 150001, China 《哈尔滨工程大学学报(英文版)》 2002年第2期18-22,共5页
In this paper, 3D track-keeping control method for autonomous underwater vehicle (AUV) with and without the influence of ocean current is investigated. Because the system to be controlled is highly nonlinear and stron... In this paper, 3D track-keeping control method for autonomous underwater vehicle (AUV) with and without the influence of ocean current is investigated. Because the system to be controlled is highly nonlinear and strong coupled, an approach is used to divide it into two subsystems. One is to control the heading and the track error on the horizontal plane. The other is to control the pitch and the track error on the vertical plane. The results of computer simulation show that the autopilot works properly, it can capture the current waypoint and turns to track the next path automatically. 展开更多
关键词 AUV SLIDING MODE CONTROL 3D track - keeping
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The Application of Air-flow to the Technological Process of Chemical Fiber
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作者 崔启亮 陈明 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期112-114,共3页
The air-flow’s states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bul... The air-flow’s states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bulked continuous filament (BCF)),and the effect of air-flow on the process and quality of chemical fiber is studied,and the action of mechanics and heat on the bulked continuous filament are calculated. 展开更多
关键词 air - flow CHEMICAL FIBER TECHNOLOGICAL process
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Air-flow Analysis for BCF Texturing Tube
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作者 崔启亮 陈明 陈人哲 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期114-116,共3页
In this paper,the Reynolds number,velocity,pressureand kinetic energy of the BCF processing hot air-floware analyzed with the help of the aero-dynamic theory,and their distributions inside the texturing tube are ob-ta... In this paper,the Reynolds number,velocity,pressureand kinetic energy of the BCF processing hot air-floware analyzed with the help of the aero-dynamic theory,and their distributions inside the texturing tube are ob-tained by pressure measuring. 展开更多
关键词 TEXTURING unit TEXTURING TUBE air - flow.
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A DUAL-CAMERA VIDEO-TRACKING SYSTEM USING PROJECTION ALGORITHM
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作者 Liu Xiaojun Zou Mouyan (Institute of Electronics, Chinese Academy of Sciences, Beijing 100080) 《Journal of Electronics(China)》 2001年第2期174-180,共7页
This paper presents a video-tracking system composed of two cameras. One camera acts for producing an in-focus image of the object and the other one ensures an extended vision field under monitoring. Such a system sch... This paper presents a video-tracking system composed of two cameras. One camera acts for producing an in-focus image of the object and the other one ensures an extended vision field under monitoring. Such a system scheme can achieve an excellent tracking performance,especially under various unfavorable conditions. A projection algorithm is used for the calculation of the displacement of the moving object. As a result, the computational cost is reduced greatly.In order that the tracking action of the system persists even if the object is sheltered or ns acceleration is larger than a specified threshold, a dedicated tracking algorithm on the basis of the α-β filtering is designed. Experiments show that the algorithm is efficient and the system works very well. 展开更多
关键词 VIDEO monitoring VIDEO trackING α-β FILTERS
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Fundamental Properties and Optimal Gains of a Steady-State Velocity Measured <i>α</i>-<i>β</i>Tracking Filter
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作者 Kenshi Saho 《Advances in Remote Sensing》 2014年第2期61-76,共16页
This paper clarifies the steady-state properties and performance of an α-β filter for moving target tracking using both position and velocity measurements. We call this filter velocity measured α-β (VM-α-β) filt... This paper clarifies the steady-state properties and performance of an α-β filter for moving target tracking using both position and velocity measurements. We call this filter velocity measured α-β (VM-α-β) filter. We first derive the stability condition and steady-state predicted errors as fundamental properties of the VM-α-β filter. The optimal gains for representative motion models are then derived from the Kalman filter equations. Theoretical and numerical analyses verify that VM-α-β filters with these optimal gains realize more accurate tracking than conventional α-β filters when the filter gains are relatively large. Our study reveals the conditions under which the predicted errors of the VM-α-β filters are less than those of conventional α-β filters. Moreover, numerical simulations clarify that the variance of the tracking error of the VM-α-β filters is approximately 3/4 of that of the conventional α-β filters in realistic situations, even when the accuracy of the position/velocity measurements is the same. 展开更多
关键词 α-β FILTER Moving Target tracking VELOCITY Measurement KALMAN FILTER OPTIMAL Gain
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Comparison of three fluorescence labeling and tracking methods of endothelial progenitor cells in laser-injured retina
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作者 Hui Shi Xin-Rui Wang +8 位作者 Ming-Chao Bi Wei Yang Dan Wang Hai-Le Liu Ling-Ling Liang Xiao-Hong Li Qian Hao Zhi-Hua Cui E Song 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第4期580-588,共9页
AIM: To compare three kinds of fluorescent probes for in vitro labeling and in vivo tracking of endothelial progenitor cells(EPCs) in a mouse model of laser-induced retinal injury.METHODS: EPCs were isolated from ... AIM: To compare three kinds of fluorescent probes for in vitro labeling and in vivo tracking of endothelial progenitor cells(EPCs) in a mouse model of laser-induced retinal injury.METHODS: EPCs were isolated from human umbilical cord blood mononuclear cells and labeled with three different fluorescent probes: 5-(and-6)-carboxyfluorescein diacetate succinimidyl ester(CFSE), 1,1′-dilinoleyl-3,3,3′,3′-tetramethylindo-carbocyanine perchlorate linked acetylated low-density lipoprotein(Di I-Ac LDL), and green fluorescent protein(GFP). The fluorescent intensity of EPCs was examined by confocal microscopy. Survival rate of labeled EPCs was calculated with trypan blue staining, and their adhesive capability was assessed. A mouse model of retinal injury was induced by laser, and EPCs were injected into the vitreous cavity. Frozen section and fluorescein angiography on flat-mounted retinal samples was employed to track the labeled EPCs in vivo.RESULTS: EPCs labeled with CFSE and Di I-Ac LDL exhibited an intense green and red fluorescence at the beginning; the fluorescence intensity decreased gradually to 20.23% and 49.99% respectively, after 28 d. On the contrary, the florescent intensity of GFP-labeled EPCs increased in a time-dependent manner. All labeled EPCs showed normal morphology and no significant change in survival and adhesive capability. In the mouse model, transplantation of EPCs showed a protective effect against retinal injury. EPCs labeled with CFSE and Di I-Ac LDL were successfully tracked in mice during the development of retinal injury and repair; however, GFP-labeled EPCs were not detected in the laser-injured mouse retina.CONCLUSION: The three fluorescent markers used in this study have their own set of advantages and disadvantages. CFSE and Di I-Ac LDL are suitable for short-term EPClabeling, while GFP should be used for long-term labeling. The choice of fluorescent markers should be guided by the purpose of the study. 展开更多
关键词 endothelial progenitor cells cell tracking 5-(and-6)-carboxyfluorescein diacetate succinimidyl ester 1 1′-dilinoleyl-3 3 3′ 3′-tetramethylindo-carbocyanine perchlorate linked acetylated low-density lipoprotein green fluorescent protein retinal laser photocoagulation
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Air Quality Regarding to TSP in Six Cities of Sonora,Mexico,a Criticism to the NOM-025-SSA1-1993 and a Proposed Criterion for Its Non-Compliance
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作者 Martin Eusebio Cruz-Campas Agustin Gomez-Alvarez +3 位作者 Margarito Quintero-Nunez Roberto Ramirez-Leal Jaime Varela-Salazar Onofre Monge-Amaya 《Journal of Environmental Protection》 2014年第10期862-873,共12页
In the present study, the air quality is assessed for the year 2010 regarding to the Total Suspended Particles (TSP) for six cities of Sonora, Mexico, representing the first regional study in Sonora in air quality. Th... In the present study, the air quality is assessed for the year 2010 regarding to the Total Suspended Particles (TSP) for six cities of Sonora, Mexico, representing the first regional study in Sonora in air quality. The assessment used performance indicators and indicators of compliance with the regulations. It is established that in all the cities the maximum limit value of daily concentration of 210 μg/m3 is exceeded, being the percentage of days above the rule of 30%, 78%, 76%, 6%, 3% and 62% for Agua Prieta, Nogales, Puerto Penasco, Hermosillo, Guaymas and Obregón respectively, classifying these days with poor air quality. According to the annualized index used, the air quality was not satisfactory for the period of study in the six cities. Nogales and Puerto Penasco presented the most adverse conditions of air quality with annual average values of TSP of 363 and 345 μg/m3 and maximum daily of 1047 and 1239 μg/m3 (498% and 590% above the norm) respectively. The requirements of coverage that establishes the Mexican Official Standard NOM-025-SSA1-1993 (SSA, 2005) are questioned for its compliance, proposing in this paper a criterion of non-compliance by prioritizing the protection of health and the precautionary principle. It is recommended to implement air quality management programs (PROAIRE) in these cities. 展开更多
关键词 Particles TSP air Quality NOM-025-SSA1-1993 Sonora Mexico
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基于航迹预测的复杂点融合系统航班排序研究
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作者 朱承元 管建华 张澈 《计算机仿真》 2024年第3期57-63,共7页
为了提高复杂点融合系统的运行效率,对复杂点融合系统的航班排序问题进行了研究。通过BADA性能数据库对航班进行航迹预测,充分考虑了系统外的冲突对点融合系统排序的影响。以进场航班的点融合系统内飞行时间最小为目标,以安全运行间隔... 为了提高复杂点融合系统的运行效率,对复杂点融合系统的航班排序问题进行了研究。通过BADA性能数据库对航班进行航迹预测,充分考虑了系统外的冲突对点融合系统排序的影响。以进场航班的点融合系统内飞行时间最小为目标,以安全运行间隔为约束条件,使用改进蝴蝶优化算法进行优化,并使用TAAM仿真软件进行仿真验证。经大量仿真,整体优化率在30%左右波动,证明了排序优化模型的鲁棒性和适用性,为点融合系统排序优化方面的研究提供了新思路。 展开更多
关键词 空中交通管制 点融合系统 仿真优化 航迹预测 蝴蝶优化算法
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天空地一体化多目标跟踪算法研究综述
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作者 闫莉萍 刘晗钊 夏元清 《信号处理》 CSCD 北大核心 2024年第11期1951-1971,共21页
为实现全时全域“泛在连接”,构建天空地一体化网络已成为国家重大需求,而基于天空地一体化网络下跨域协同系统进行多目标跟踪是其中一个重要的发展方向,其在军民用领域都极具应用价值。本文详细阐述了天空地一体化网络背景下多目标跟... 为实现全时全域“泛在连接”,构建天空地一体化网络已成为国家重大需求,而基于天空地一体化网络下跨域协同系统进行多目标跟踪是其中一个重要的发展方向,其在军民用领域都极具应用价值。本文详细阐述了天空地一体化网络背景下多目标跟踪方法研究进展。首先,介绍了天空地一体化跨域协同多目标跟踪的研究背景与意义。其次,从基于视觉的多目标跟踪、基于模型的多目标跟踪和基于多模态融合的多目标跟踪三个方面概述了当前的代表性研究方法:在基于视觉的多目标跟踪算法方面,介绍了单摄像头和多摄像头融合的多目标跟踪方法;对于基于模型的多目标跟踪,先介绍了单传感器多目标跟踪方法,以及在多种复杂场景下的改进,然后介绍了多传感器融合方法;在基于多模态信息融合的目标跟踪方面,在对多传感器时空配准方法和有代表性的多模态信息融合方法介绍的基础上,概括了基于多模态融合的多目标跟踪算法。最后探讨了当前存在的问题和未来发展方向:无论基于视觉的还是基于模型的多目标跟踪方法都有不少问题有待解决,特别是两种方法的结合值得深入研究;在面临复杂干扰时,基于多传感器信息融合的多目标跟踪由于能实现信息的互补,成为未来的主流发展方向;此外,跨域协同系统,由于能利用更多的资源和信息,其多目标跟踪问题研究极具价值,不过其中通信安全问题和多目标跟踪模型轻量化问题值得探讨。本文对从事目标跟踪及空天地一体化协同控制相关理论与技术研究的科研工作者具有重要参考价值。 展开更多
关键词 天空地一体化 视觉目标跟踪 随机有限集 多模型 多模态信息融合
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基于反步法的空气处理机组温湿度跟踪控制
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作者 尚芳 彭伟 +1 位作者 汲永帅 尹绎凯 《山东建筑大学学报》 2024年第5期86-92,共7页
针对空气处理机组室内湿负荷和进回水温差不确定的情况,提出一种带有多参数的反步控制器,可以实现温度和湿度的跟踪控制。为了设计方便,先将空气处理机组的动态模型转换为状态空间表达形式,通过引入带增益的状态变换,将原系统的跟踪控... 针对空气处理机组室内湿负荷和进回水温差不确定的情况,提出一种带有多参数的反步控制器,可以实现温度和湿度的跟踪控制。为了设计方便,先将空气处理机组的动态模型转换为状态空间表达形式,通过引入带增益的状态变换,将原系统的跟踪控制问题转换为变换后所得新系统的稳定控制问题;利用反步法逐步设计了控制器,并通过选择合适的设计参数,实现了温度和湿度的跟踪控制目标;分析了闭环系统的稳定性并给出了证明过程。结果表明:仿真实验验证了所研控制器的有效性,通过与PID控制器对比可知,所设计控制器的跟踪效果更好。 展开更多
关键词 空气处理机组 反步法 不确定参数 跟踪控制
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空地一体化测绘多无人机飞行协同控制方法
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作者 刘锋 刘鹏 《科技通报》 2024年第10期21-24,共4页
针对多无人机在协同编队飞行过程中通信信息利用率低,导致无人机轨迹规划效果差、效率低等问题,本文提出了一种空地一体化测绘多无人机飞行协同控制方法。利用A*算法改进一致性算法,对多个共同飞行的无人机实行任务分配,通过改进的一致... 针对多无人机在协同编队飞行过程中通信信息利用率低,导致无人机轨迹规划效果差、效率低等问题,本文提出了一种空地一体化测绘多无人机飞行协同控制方法。利用A*算法改进一致性算法,对多个共同飞行的无人机实行任务分配,通过改进的一致性算法实行轨迹规划。根据无人机航向角、飞行高度和速度等信息,对无人机进行编队控制,实现多无人机飞行协同控制。实验结果表明:所提方法避障效果较优,适用于各类对多无人机控制精度要求较高的工作。 展开更多
关键词 空地一体化 多无人机飞行 协同控制 任务分配 轨迹规划
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预浓缩系统与GC-MS联用测定环境空气中痕量挥发性有机物 被引量:20
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作者 徐能斌 应红梅 +1 位作者 朱丽波 俞杰 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期198-201,205,共5页
  目前,国内空气质量监测普遍停留在燃煤、汽车尾气引起的无机污染物(二氧化硫、二氧化氮)阶段,而对易对人体产生三致作用(致癌、致畸、致突变)的挥发性有机物(VOCs)监测由于技术原因尚未开展.现在,挥发性有机物(VOCs)对室内外空气质...   目前,国内空气质量监测普遍停留在燃煤、汽车尾气引起的无机污染物(二氧化硫、二氧化氮)阶段,而对易对人体产生三致作用(致癌、致畸、致突变)的挥发性有机物(VOCs)监测由于技术原因尚未开展.现在,挥发性有机物(VOCs)对室内外空气质量及人体健康的影响已日益受到人们的关注,同时也成为国内外研究的焦点.…… 展开更多
关键词 VOCS GC - MS Ambient air
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