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arXiv 2025年

作者： Yahn, Zachary Trent, Douglas M. Duncan, Ethan Seignovert, Benoît Santerre, John Nixon, Conor A. School of Computer Science Georgia Institute of Technology AtlantaGA United States Planetary Systems Laboratory NASA Goddard Space Flight Center GreenbeltMD United States Informatio Data & Analytics Services NASA Langley Research Center HamptonVA United States School of Information University of California Berkeley BerkeleyCA United States Observatoire des Sciences de l'Univers Nantes Atlantique Osuna UAR Nantes3281 France

Despite widespread adoption of deep learning models to address a variety of computer vision tasks, planetary science has yet to see extensive utilization of such tools to address its unique problems. On Titan, the largest moon of Saturn, tracking seasonal trends and weather patterns of clouds provides crucial insights into one of the most complex climates in the Solar System, yet much of the available image data are still analyzed in a conventional way. In this work, we apply a Mask R-CNN trained via transfer learning to perform instance segmentation of clouds in Titan images acquired by the Cassini spacecraft-a previously unexplored approach to a "big data" problem in planetary science. We demonstrate that an automated technique can provide quantitative measures for clouds, such as areas and centroids, that may otherwise be prohibitively time‐intensive to produce by human mapping. Furthermore, despite Titan‐specific challenges, our approach yields accuracy comparable to contemporary cloud identification studies on Earth and other worlds. We compare the efficiencies of human‐driven versus algorithmic approaches, showing that transfer learning provides speed‐ups that may open new horizons for data investigation for Titan. Moreover, we suggest that such approaches have broad potential for application to similar problems in planetary science where they are currently under‐utilized. Future planned missions to the planets and remote sensing initiatives for the Earth promise to provide a deluge of image data in the coming years that will benefit strongly from leveraging machine learning approaches to perform the analysis. © 2025, CC BY.

关键词： Image segmentation

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Driving condition recognition for genetic-fuzzy HEV control

Driving condition recognition for genetic-fuzzy HEV control

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2008 3rd International Workshop on Genetic and Evolving Fuzzy systems, GEFS

作者： Montazeri-Gh, M. Ahmadi, A. Asadi, M. Department of Mechanical Engineering Systems Simulation and Control Laboratory IUST Systems Simulation and Control Laboratory Department of Mechanical Eng Iran University of Science and Technology Narmak Tehran 16844 Iran

ISBN: (纸本)9781424416134

This paper presents a genetic-fuzzy approach for hybrid electric vehicle control based on driving pattern recognition and prediction. In this approach, data collection in the real traffic conditions is employed for classification of several driving patterns. These driving patterns represent different traffic conditions e.g. congested, urban and so on. The analysis used for the driving pattern recognition is based on the definition of microtrips. In addition, a Markov chain modeling is used for traffic condition prediction based on the modeling of probability of the sequence of microtrips. The driving pattern prediction is then utilized for optimization of the HEV control parameters using a genetic-fuzzy approach. In this approach, a fuzzy logic controller (FLC) is designed to be intelligent so as to manage the internal combustion engine (ICE) to work in the vicinity of its optimal condition. The fuzzy membership function parameters are then tuned using the genetic algorithm (GA). Finally, simulation results are presented to show the effectiveness of the approach for reducing the HEV fuel consumption and emissions. © 2008 IEEE.

关键词： Forecasting

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Network Evaluation and Protocol Deployment for Complex Deep-space Networks Based on DTN

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China Communications 2020年第9期17卷 237-258页

作者： Guo Yu Zhenxing Dong Yan Zhu Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Previous research on deep-space networks based on delay-tolerant networking(DTN)has mainly focused on the performance of DTN protocols in simple networks;hence,research on complex networks is *** this paper,we focus on network evaluation and protocol deployment for complex DTNbased deep-space networks and apply the results to a novel complex deep-space network based on the Universal Interplanetary Communication Network(UNICON-CDSN)proposed by the National space science Center(NSSC)for simulation and verification.A network evaluation method based on network capacity and memory analysis is *** on a performance comparison between the Licklider Transmission Protocol(LTP)and the Transmission Control Protocol(TCP)with the Bundle Protocol(BP)in various communication scenarios,a transport protocol configuration proposal is developed and used to construct an LTP deployment scheme for *** the LTP deployment scheme,a theoretical model of file delivery time over complex deep-space networks is built.A network evaluation with the method proposed in this paper proves that UNICONCDSN satisfies the requirements for the 2020 Mars exploration mission ***,simulation results from a universal space communication network testbed(USCNT)designed by us show that the LTP deployment scheme is suitable for UNICON-CDSN.

关键词： complex deep-space network network capacity memory analysis protocol deployment testbed

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The compliance contact model of cylindrical joints with clearances

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Acta Mechanica Sinica 2005年第5期21卷 451-458页

作者： Caishan Liu Ke Zhang Lei Yang Department of Mechanics and Engineering Science State Key Laboratory of Turbulence and Complex SystemsPeking University Beijing 100871 China Chinese Academe of Space Technology Beijing 100086 China

This paper is concerned with the determination of the normal force-displacement （NFD） relation for the contact problem of cylindrical joints with clearance. A simple formulation for this contact problem is developed by modeling the pin as a rigid wedge and the elastic plate as a simple Winkler elastic foundation. The numerical results show that the normal displacement relation based on Hertz theory is only valid for the case of large clearance with a small normal load, and the NFD relation based on Persson theory is only effective in the case of very small clearance. The proposed approximate model in this paper gives better results than Hertz theory and Persson theory in a large range of clearances as seen from the comparison with the results of FEM.

关键词： Cylindrical joint with clearance .Conformalcontact. FEM

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Pseudo complementary measurement for traditional single-pixel cameras

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Chinese Physics B 2020年第11期29卷 315-322页

作者： Qian Dong Xu-Ri Yao Xin Liu Bing Liu Guang-Jie Zhai State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing 100190China Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China State Key Laboratory of Scientific and Engineering Computing Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

A traditional single-pixel camera needs a large number of measurements to reconstruct the object with compressive sensing *** with the 1/0 matrices in classical measurement,the 1/-1 matrices in the complementary measurement has better property for reconstruction computation and returns better reconstruction ***,each row of the 1/-1 matrices needs two measurements with the traditional single-pixel camera which results into double measurements compared with the 1/0 *** this paper,we consider the pseudo complementary measurement which only takes the same amount of measurements with the row number of some properly designed 1/0 matrix to compute the total luminous flux of the objective and derives the measurement data of the corresponding 1/-1 matrix in a mathematical *** numerical simulation and experimental result show that the pseudo complementary measurement is an efficient tool for the traditional single-pixel camera imaging under low measurement rate,which can combine the advantages of the classical and complementary measurements and significantly improve the peak signal-to-noise ratio.

关键词： computational imaging single-pixel camera

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Forest or grassland? A quantitative analysis of urban residents' green exposure preference by using multi-temporal mobile signal data

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Urban Forestry and Urban Greening 2025年 108卷

作者： Geng, Hongkai Lin, Tao van Bodegom, P.M. Hu, Mingming Zheng, Yicheng Jia, Zixu Zhang, Junmao Guo, Xiangzhong Chen, Yuan Lin, Meixia Cai, Jiayu Lin, Jing Key Laboratory of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China University of Chinese Academy of Sciences Beijing 100049 China Fujian Key Laboratory of Digital Technology for Territorial Space Analysis and Simulation Fuzhou 350108 China State Key Laboratory of Regional and Urban Ecology Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China Institute of Environmental Sciences (CML) Leiden University Leiden Netherlands School of Geographical Sciences Faculty of Science and Engineering University of Nottingham Ningbo 315100 China School of Architecture and Urban-Rural Planning Fuzhou University Fuzhou 350108 China

Urban forests and grasslands provide diverse services from their unique characteristics. Optimizing green spaces by understanding urban residents’ preferences is a critical challenge for sustainable city development amid limited land resources. However, the mechanism influencing exposure across various types of green remains unclear. This study utilized multi-temporal mobile signal data from Shanghai to quantify the exposure intensity (EI) and density (ED) for forests and grasslands. These metrics addressed the gap by revealing spatiotemporal variations in exposure preference (EP) and related socioeconomic influences. Specifically, the study addressed two key questions: (1) Do urban residents exhibit preferences between forests and grasslands in terms of EI and ED? (2) How do socioeconomic features influence these preferences? Results showed: (1) Forests had almost double the annual EI (542.86 p/h) and ED (2.69 p/m²/h) of grasslands (P < 0.001). However, grasslands in central regions exhibited significantly higher ED (13.60 vs. 11.83 p/m²/h;P < 0.001). (2) Commercial House (34.4 % importance) and Sports & Recreation (15.7 %) maximized green exposure, while Road Furniture reduced it. (3) Evening exposure peaks in central regions extended by 1 hour due to commercial-cultural synergies. Forest ED, highly driven by Commercial House, clustered in central cores and specific non-central communities, whereas Road Furniture most negatively impacted central periphery communities. These findings directly inform differentiated urban planning strategies: forests should prioritize improving accessibility to sustain prolonged exposures, while grasslands need spatial optimization to accommodate peak social demand. By aligning green space planning with socioeconomic drivers, cities can enhance the effectiveness of their service under land constraints. © 2025 Elsevier GmbH

关键词： Exposure preference Green exposure Machine learning Multi-scale geographically weighted regression Urban green space

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Design and analysis of switching reduced-order observer and separation principle for T-S fuzzy system

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science in China(Series F) 2009年第7期52卷 1217-1232页

作者： YAN ShiYu SUN ZengQi State Key Laboratory of Intelligent Technology and Systems Department of Computer Science and Technology Tsinghua UniversityBeijing 100084 China National Laboratory of Space Intelligent Control Beijing 100190 China

This paper designs and analyzes switching fuzzy reduced-order observer and proves that the corre- sponding separation principle does hold. A numerical simulation and comparison with smooth fuzzy full-order observer ar... 详细信息

关键词： switching fuzzy controller switching fuzzy reduced-order observer separation principle

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Metamaterial absorbers realized in an X-band rectangular waveguide

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Chinese Physics B 2012年第11期21卷 474-478页

作者：黄勇军文光俊李建钟靖平王平孙元华 O.Gordon 朱卫仁 Key Laboratory of Broadband Optical Fiber Transmission&Communication Networks School of Communication and Information EngineeringUniversity of Electronic Science and Technology of China Advanced Computing and Simulation Laboratory(AχL) Department of Electrical and Computer Systems EngineeringMonash University

In this paper, we demonstrate six types of metamaterial absorbers （MMAs） by measuring their absorptivities in an X-band （8 12 GHz） rectangular waveguide. Some of the MMAs have been demonstrated previously by using the free space measurement method, and the others are proposed firstly in this paper. The measured results show that all of the six MMAs exhibit high absorptivities above 98%, which have similar absorbing characteristics to those measured in the free space. The numerically obtained surface current densities for each MMA show that the absorbing mechanism is the same as that under the free space conditions. Such a demonstration method is superior to the conventional free space measurement method due to the small-scale test samples required, the simple measure device, and its low cost. Most importantly, the proposed method opens a way to enable MMAs to be used in microwave applications such as matched terminations.

关键词： metamaterial absorber electric resonator rectangular waveguide

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Bias-dependent timing jitter of 1-GHz sinusoidally gated InGaAs/InP avalanche photodiode

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Chinese Physics B 2016年第11期25卷 662-667页

作者：朱阁郑福王超孙志斌翟光杰赵清 School of Physics Beijing Institute of Technology Beijing 100081 China University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Electronics and Information Technology for Space Systems National Space Science Center Chinese Academy of Sciences Beijing 100190 China

We characterized the dependence of the timing jitter of an InGaAs/InP single-photon avalanche diode on the excess bias voltage（V（ex）） when operated in 1-GHz sinusoidally gated *** single-photon avalanche diode was cooled to-30 degrees *** the V（ex） is too low（0.2 V-0.8 V） or too high（3 V-4.2 V）,the timing jitter is increased with the V（ex）,particularly at high V（ex）.While at middle V（ex）（1 V-2.8 V）,the timing jitter is *** of the timing jitter of the same avalanche diode with pulsed gating show that this effect is likely related to the increase of both the amplitude of the V（ex） and the width of the gate-on *** the 1-GHz sinusoidally gated detector,the best jitter of 93 ps is achieved with a photon detection efficiency of 21.4%and a dark count rate of -2.08×10 -5 per gate at the V（ex） of 2.8 *** evaluate the whole performance of the detector,we calculated the noise equivalent power（NEP） and the afterpulse probability（P（ap））.It is found that both NEP and P（ap） increase quickly when the V（ex） is above 2.8 *** -2.8-V V（ex）,the NEP and P（ap） are -2.06×10-（16）W/Hz-（1/2） and 7.11%,***,the detector should be operated with V（ex） of 2.8 V to exploit the fast time response,low NEP and low P（ap）.

关键词： jitter gated timing photodiode operated quickly likely gating photon cooled

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The simulation of cluster bombs’ damage efficiency and analysis of damage factor

The simulation of cluster bombs’ damage efficiency and anal...

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International Conference on Future Communication technology and Engineering, FCTE 2014

作者： Liu, S. Zhao, X.J. Zhao, F. Wei, X. Li, W.F. Science and Technology on Complex Land Systems Simulation Laboratory Beijing China Chinese Defense Science and Technology Information Centre Beijing China

ISBN: (纸本)9781138027770

First, the paper emulated cluster bombs’random point of fall, the radius of damage of the bombs, drew the bombs’ damage range, and counted the damage effect. The final damage efficiency of cluster bombs was calculated and the influence from each damage factor of the cluster bombswas studied through many random experiences. The method solved the tough problem of the precise calculation of damage efficiency, which was caused by the overlapped damage size. © 2015 Taylor & Francis Group, London.

关键词： Efficiency

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