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International Conference on Geoinformatics

作者： Yunqiang Zhu Chunxia Guo Runda Liu Rajan Man Bajracharya Shifeng Fang State Key Lab of Resources and Environmental Information System Chinese Academy of Sciences Beijing China University of Chinese Academy of Sciences Beijing China Beijing Science & Technology Communication Center Beijing China International Centre for Integrated Mountain Development Nepal Xinjiang Academy of Environmental Protection Science Urumqi China

ISBN: (纸本)9781467376648

There have been considerable growth in awareness of Geographic information system (GIS) in the Hindu Kush-Himalayan (HKH) region, and there are initiatives underway for developing regional Spatial Data Infrastructures (SDIs). Such infrastructures are being advocated to fulfill the gaps in data standards, data sharing protocols and software platform so that resources can be saved from duplications and societies can benefit from easy access to data. These initiatives include sharing of data such as basic geographic map, socio-economic data, environmental or disaster related data etc. These activities advance scientific discovery and help decision makers to tackle problems caused by global climate change, promote regional sustainable development and better the lives of people living in this region. However, harmonizing data at various levels and across different disciplines is challenging as these data platforms are usually heterogeneous and lack inter-connection. Activities of cross-border data sharing is not well implemented, its sharing practice requires unique technical standards and specific software platforms. China has growing interests to participate in data sharing activities in HKH region, an initiative was set up to conduct pilot researches to promote HKH region data sharing. One of the components of this initiative is to build a HKH region data sharing network (platform) in close collab.ration with International Centre for Integrated Mountain Development (ICIMOD) and other related agencies in the region. This paper mainly focuses on the technical aspect, study on the technical standards and software platform selection in the process of building the network. It reviews relating data sharing network across the world and in HKH region. The study believes that the emergence and maturity of open source software and service models reduced the difficulty in constructing platform for data sharing. Open source software is open, flexible, and low cost and supports a

关键词： Metadata Standards Software

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A unified leader-follower scheme for mobile robots with uncalibrated on-board camera

A unified leader-follower scheme for mobile robots with unca...

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IEEE International Conference on Robotics and Automation (ICRA)

作者： Dejun Guo Hesheng Wang Weidong Chen Ming Liu Zeyang Xia Kam K. Leang DARC (Design Automation Robotics & Control) Lab University of Utah Robotics Center Salt Lake City Utah USA State Key Laboratory of Robotics and System (HIT) Key Laboratory of System Control and Information Processing Ministry of Education of China Department of Automation Shanghai Jiao Tong University Shanghai China Department of Electronics and Computer Engineering Hong Kong University of Science and Technology Hong Kong China Institute of Biomedical and Health Engineering Chinese Academy of Sciences Shenzhen China

This paper studies the problem of image-based leader-follower formation control for mobile robots, where the controller is designed independently of the leader's motion. An adaptive control scheme, which is suitable for both omnidirectional and perspective cameras, is proposed. The proposed approach avoids the need for accurate calibration of the extrinsic parameters of the omnidirectional camera as well as the intrinsic and extrinsic parameters of perspective camera. Additionally, the coefficients of the plane where the feature point moves relative to the camera frame can be uncertain. These uncertain constant parameters are estimated using an adaptive estimator. Uniform Semi-global Practical Asymptotic Stability (USPAS) of the system is shown using the Lyapunov approach. Experimental results are presented to demonstrate the effectiveness of the proposed control scheme.

关键词： Cameras Robot vision systems Kinematics Mobile robots Calibration Automation

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Energy-efficient Contact Probing in Opportunistic Mobile Networks

Energy-efficient Contact Probing in Opportunistic Mobile Net...

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International Conference on Computer communications and Networks

作者： Huan Zhou Huanyang Zheng Jie Wu Jiming Chen State Key Lab. of Industrial Control Technology Zhejiang University Hangzhou China Department of Computer and Information Sciences Temple University USA

In Opportunistic Mobile Networks (OppNets), data is opportunistically exchanged between nodes who encounter each other. In order to enable such data exchanges, nodes in the network have to probe their environment continually, so as to discover neighbor nodes. This can be an extremely energy-consuming process. If nodes probe very frequently, they will consume a lot of energy, and might be energy inefficient. On the other hand, infrequent contact probing might cause nodes to miss many of their contacts, and thus opportunities to exchange data are lost. Therefore, there exists a trade-off between energy efficiency and the contact opportunities in OppNets. In this paper, in order to investigate this trade-off, we first propose a model to quantify the detecting probability in OppNets, using the Random WayPoint (RWP) model. Then, extensive simulations are conducted to validate the correctness of our proposed model. Finally, based on the proposed model, we analyze the tradeoff between energy efficiency and the total number of effective contacts under different situations. Our results show that the good trade-off points are obviously different when the speed of nodes is different. Moreover, the detecting probability increases as the speed of nodes decreases, while the total number of effective contacts increases as the speed of nodes increases.

关键词： Opportunistic Mobile Networks Energy consumption Contact probing Random WayPoint model

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Deterministic bulk-boundary correspondences for skin and edge modes in a general two-band non-Hermitian system

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Physical Review Research 2022年第4期4卷 043222-043222页

作者： Chong Hou Lingfang Li Shihua Chen Yi Liu Luqi Yuan Yiqi Zhang Zhenhua Ni School of Physics and Frontiers Science Center for Mobile Information Communication and Security Southeast University Nanjing 211189 China Purple Mountain Laboratories Nanjing 211111 China Shanghai Key Lab of Modern Optical System University of Shanghai for Science and Technology Shanghai 200093 China CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800 China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240 China Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Lab of Information Photonic Technique School of Electronic Science and Engineering Faculty of Electronic and Information Engineering Xi'an Jiaotong University Xi'an 710049 China

In isolated Hermitian systems, the bulk-boundary correspondence is generally thought of as a compelling principle guiding the occurrence of robust edge states through the topological invariants of the bulk. However, in open non-Hermitian systems that support non-Hermitian skin effects, the universality of the bulk-boundary correspondence has so far remained disputable in spite of being subjected to intensive studies. Here we provide analytical and numerical evidence of bulk-boundary correspondences for both skin and edge modes in 1D two-band non-Hermitian systems within the framework of a prototypical non-Hermitian Su-Schrieffer-Heeger model. Two different topological winding numbers, one on a Brillouin zone and the other on a generalized Brillouin zone, are defined to fully characterize the topological phases of matter and to understand such deterministic correspondences. In addition to the exact solutions for bulk states, we also obtain explicit solution forms for edge modes along with analytical conditions for their existence and localization, all exhibiting remarkable agreement with numerical results. Our results solve the elusive non-Hermitian topology and may facilitate experimental investigations of bulk-boundary correspondence in a wide range of non-Hermitian systems.

关键词： Edge states Skin effect Topological phases of matter Non-Hermitean systems Topological materials

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2D Structured Turbo Compressed Sensing for Channel Estimation in OTFS systems

2D Structured Turbo Compressed Sensing for Channel Estimatio...

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International Conference on communication systems

作者： Mingchen Zhang Fanggang Wang Xiaojun Yuan Lei Chen Center for Intelligent Networking and Commun National Key Lab. of Sci. and Tech. on Commun University of Electronic Sci. and Tech. of China Chengdu China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China School of Information Science and Technology ShanghaiTech University Shanghai China

ISBN: (纸本)9781538678657;9781538678640

High-speed mobility is a challenging scenario in wireless communications since it involves fast-varying channels, in which orthogonal frequency-division multiplexing (OFDM) could degrade significantly without accurate Doppler compensation. Recently, a modulation called orthogonal time frequency space (OTFS) was proposed for the specific scenario. The advantages are two-fold, i.e., the orthogonality in the time-frequency domain and the clustered sparsity of channel information in the delay-Doppler domain. In this paper, we propose a two-dimensional structured Turbo compressed sensing (CS) algorithm based on our previous work on Turbo CS for fast time-varying channel estimation. Markov random field is applied to model the clustered sparse prior of the channel in the two-dimensional delay-Doppler domain. In contrast to the conventional Turbo CS, a two-dimensional structured minimum mean-square error (MMSE) estimator is designed by message passing over a Markov random field. The convergence and the MSE performance of the proposed algorithm is evaluated, and the simulation results validate that the proposed algorithm outperforms the existing algorithms.

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Research on Adaptive Navigation system of Mountain Orchard Plant Protection Unmanned Aerial Vehicle Based on Simultaneous Localization and Mapping and Global Navigation Satellite system Fusion

Research on Adaptive Navigation System of Mountain Orchard P...

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Electronic information technology and Smart Agriculture (ICEITSA), International Conference on

作者： Xuan Ouyang Xujun Liu Xiangkai Xu Yingjing Qian Qingli Zeng College of Communication and Electronic Engineering Jishou University Jishou Hunan P.R. China College of Automation and Electronic Information Xiangtan University Xiangtan Hunan P.R. China Hunan Provincial Key Lab. of Intelligent Control Technology for Ecological Agriculture in Wuling Mountain Area Huaihua University Huaihua Hunan P.R. China

ISBN: (纸本)9781665464024

China's western terrain is dominated by mountains, plateaus and basins, and the east is dominated by plains and hills. The mountainous area occupies 2/3 of the total national area. Due to the restriction of terrain conditions, the mechanization degree of orchard management is not high, and the lab.r intensity of fruit farmers is large and the cost is high. The desire of fruit farmers for orchard mechanization management and protection is very urgent. This system in view of the four rotor unmanned aerial vehicle developed a terrain adaptive landing gear, analysis of the terrain recognition algorithm, combined with mountain orchard plant protection drone operation requirements, the plant protection drones take operation line extraction method, the optimal path for homework, according to the characteristics of the fruit tree distribution research combines visual simultaneous localization and mapping technology and global navigation satellite system technology level of unmanned aerial vehicle navigation control method, It is of great research and economic value to combine the above methods and build an adaptive navigation control system suitable for quadrotor plant protection unmanned aerial vehicle operation in mountain orchards, and to establish an adaptive navigation system for mountain orchard plant protection unmanned aerial vehicle.

关键词： Solid modeling Global navigation satellite system Adaptive systems Simultaneous localization and mapping Gears Autonomous aerial vehicles control systems

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Performance Analysis of Cooperative HADF Relaying V2I communication systems for ND-symbol Burst Transmission using PSA-CE methods Over Quasi-Static Rayleigh Fading channels

Performance Analysis of Cooperative HADF Relaying V2I Commun...

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17th International IEEE Conference on Intelligent Transportation systems & The Asia-Pacific Council on systems Engineering Conference 2014

作者： Min Baek Gilwon Seo Chungha Bong Kyunbyoung Ko the Convergence-Information Technology Research Center for Next-Generation Intelligent Transport System (C-ITRC for NGITS) the Communication and Signal Processing Lab.(CSPL)the Department of IT ConvergenceKorea National University of Transportation50 Daehak-roChungju-siChungbuk380-702 Korea the Department of Control and Instrumentation Engineering Korea National University of Transportation50 Daehak-roChungju-siChungbuk380-702 Korea

In this paper,we derive the average symbol error rate(SER) for the ND-symbol burst hybrid adaptive decodeor-amplify-forward(HADF) relaying vehicle-to-infrastructure(V2I) communication systems over quasi-static independent and non-identical distributed(INID) Rayleigh fading *** proposed analytical approach includes channel estimation(CE)errors generated by practical pilot symbol assisted-CE(PSACE) ***,based on the error-events at relaying on board equipments(OBEs) for ND-symbol burst data transmission,the conditional SER expression has been derived as an exact ***,the approximated average SER(ASER)expressions are presented as the closed-forms and their accuracy is confirmed by the comparison with simulation ***,we can conclude that our analytical expressions are tractable forms,and can be used as a tool to verify effects of an erroneous detection and hybrid transmission at each relaying OBE on the combined signal-to-noise ratio(SNR) and ASER for cooperative HADF relaying communication systems.

关键词： SNR ADF Performance Analysis of Cooperative HADF Relaying V2I communication systems for ND-symbol Burst Transmission using PSA-CE methods Over Quasi-Static Rayleigh Fading channels Rayleigh

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A novel energy-saving train operation strategy based on particle swarm algorithms

A novel energy-saving train operation strategy based on part...

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Chinese Automation Congress (CAC)

作者： Hao Wang Yuxuan Li Hongli Zhao Xinjun Gao China Railway Siyuan Survey and Designing Group CO. LTD Wuhan China State Key Lab. of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China School of Electronics and Information Engineering Beijing Jiaotong University Beijing P.R China Sciences Signal and Communication Research Institute China Academy of Railway Beijing China

ISBN: (纸本)9781665426480

To effectively reduce the energy consumption of urban rail transit trains and optimize the operation strategy, based on the dynamic model of the urban rail transit train, the energy consumption model of four-stage manipulation strategy is constructed respectively, and the particle swarm optimization algorithm is used to solve the model. In this paper, an Atype train with four driving and two pallets are selected as the research object, and a case design is carried out on a flat ramp. The operation strategy is analyzed for the difference between vehicle traction energy consumption, regenerative braking energy storage, and total energy consumption. The corresponding speed-distance curve is obtained by simulation. The results show that the four-stage control strategy is generally helpful to achieve better energy-saving optimization effects.

关键词： Rails Energy consumption Heuristic algorithms Force Particle swarm optimization Vehicle dynamics Pallets

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Research on Highly Anti-Humidity and Selective NO2 Detection Based on GaN/MoO3 N-N Heterojunction

SSRN

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SSRN 2024年

作者： Hong, Yutao Han, Dan Li, Donghui He, Xiuli Zhao, Li Wang, Weidong Li, Hongwei Sang, Shengbo Liang, Hua Shanxi Key Laboratory of Micro Nano Sensors & Artificial Intelligence Perception College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan030024 China Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan030024 China State Key Laboratory of Transducer Technology Aerospace Information Research Institute Chinese Academy of Sciences Beijing100190 China Bioengineering Research Center Medical Innovation Research Division Chinese PLA General Hospital Beijing China Shanxi Academy of Medical Sciences China

Effective and accuratedetection of NO2 gas is crucial for protecting the environment and public health. In this work, balsam pear-like GaN/MoO3 porous nanosheets (GaN/MoO3) composites were synthesized by the in situ assembling, the hydrothermal method, and the nitridation process to detect NO2. A series of characterization methods were used to manifest the successful synthesis and to analyze the morphology and elemental composition features of GaN/MoO3 composites. The results of the gas-sensing experiments show that at the operating temperature of 225 °C, the gas sensor based on the optimal ratio of GaN/MoO3 composites exhibits a low theoretical limit of detection (0.78 ppb) for NO2, which is significantly improved compared with the limit of detection of MoO3 (5 ppm). Further, the response value of the sensor based on GaN/MoO3 composites to 200 ppm NO2 (44.74) is 4.36 times higher than that of the sensor based on pure GaN, with an improvement in stability. Meanwhile, the sensor also possessed excellent repeatability, selectivity, stability, and splendid anti-humidity ability at 15-70 % RH. The improved gas-sensing performance is ascribed to the unique microstructure of both GaN and MoO3, and the heterojunction effect between them. This work provides a way to improve the efficiency and anti-humidity ability of real-time monitoring of NO2 for the sensors of MoO3-based composite. © 2024, The Authors. All rights reserved.

关键词： Gallium nitride

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A Practical and High-Performance Nitrogen Dioxide Gas Sensor that Can Be Rapidly Mass-Produced Based on Gallium Nitride Quantum Dots Film

SSRN

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SSRN 2022年

作者： Han, Dan Chen, Yi Li, Donghui Dong, Hailiang Xu, Bingshe Sang, Shengbo He, Xiuli Shanxi Key Laboratory of Micro Nano Sensors & Artificial Intelligence Perception College of Information and Computer Taiyuan University of Technology Taiyuan030024 China Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan030024 China Key Laboratory of Interface Science and Engineering in Advanced Materials Taiyuan University of Technology Ministry of Education Taiyuan030024 China State Key Laboratory of Transducer Technology Aerospace Information Research Institute Chinese Academy of Sciences Beijing100190 China Shanxi Research Institute of 6D Artificiat Intelligence Biomedical Science Taiyuan030024 China

Gallium nitride (GaN) has some challenges for gas sensing, such as high detection lower limit (LOD) or controlling the epitaxy of nanostructures. To address these issues, we exclusively designed a device to enhance the gas interaction capabilities of GaN quantum dots (QDs) film fabricated by metal-organic chemical vapor deposition (MOCVD). The GaN QDs film gas sensor exhibited a low LOD (5 ppb) to NO2 at room temperature (RT), which has much superior gas performance than other GaN-based sensors. The results manifest that many ultra-small QDs around 2 nm in diameter are stacked to form QDs of larger size, and confirm the existence of vacancies. The sensor displays a ultra-high electron mobility of 1237.37 cm2 V−1s−1, demonstrate that great shallow donor impurities in GaN QDs film that ionize easily at RT, which is greatly beneficial for gas sensing. The sensing mechanisms were analyzed based on its abundant active sites, ultrahigh carrier mobility, high surface energy and chemical activity, grain boundary barrier and good electrical conductivity. Moreover, the sensor processes high selectivity, repeatability, stability and reusability based on MOCVD technology which can realize precise control of structure, morphology and surface energy level, which is expected to achieve rapid industrialization. © 2022, The Authors. All rights reserved.

关键词： Gallium nitride

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