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Cooperative formation control of multiple aerial vehicles based on guidance route in a complex task environment

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Chinese Journal of Aeronautics 2020年第2期33卷 701-720页

作者： Guibin SUN Rui ZHOU Kun XU Zhi WENG Yuhang ZHANG Zhuoning DONG Yingxun WANG School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China State Key Laboratory of Software Development Environment Beihang UniversityBeijing 100083China College of Electronic Information Engineering Inner Mongolia UniversityHohhot 010021China

In recent years,formation control of multi-agent has been a significant research subject in the field of cooperative ***,previous works have mainly concentrated on formation control for simple point-mass model and linear *** contrast,this paper presents a novel cooperative algorithm for multiple air vehicles formation control,which aims to devise a control strategy based on guidance route to achieve precisely coordinated formation control for a group of fixed-wing aircraft in a complex task *** proposed method introduces the leader-follower structure for effective organization of the multi-agent ***,the Partial Integrated Formation and Control(PIFC)is adopted to design the control law for Guidance-route based Formation Control(GRFC).Additionally,the proposed approach designs two guidance-route generation strategies for two special situations to demonstrate the effectiveness of GRFC in complex task *** analysis reveals that the proposed control protocol for guidance command can ensure the overall stability and tracking accuracy of the *** simulations are performed to illustrate the theoretical results,and verify that the proposed approach can achieve coordinated formation control precisely in a complex task environment.

关键词： Complex task environments Cooperative formation control Fixed-wing aircraft Guidance route Leader-follower structure Partial integrated formation and control

Amorphous and Crystallizable Thermoplastic Polyureas Synthesized through a One-pot Non-isocyanate route

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Chinese Journal of Polymer Science 2019年第1期37卷 43-51,1-3页

作者： Jia-Long Ban Su-Qing Li Chen-Feng Yi 赵京波 Zhi-Yuan Zhang Jun-Ying Zhang Key Laboratory of Carbon Fiber and Functional Polymers (Beijing University of Chemical Technology) Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology

A simple one-pot non-isocyanate route for synthesizing thermoplastic polyureas is presented. In situ urethanization was conducted from the ring-opening reaction of ethylene carbonate with poly(propylene glycol) bis(2-aminopropyl ether) and hexanediamine,m-xylylenediamine, or diethylene glycol bis(3-aminopropyl) ether at 100 °C for 6 h under normal pressure. Melt transurethane polycondensation was successively conducted at 170 °C under a reduced pressure of 399 Pa for different time periods. A series of nonisocyanate thermoplastic polyureas(NI-TPUreas) were prepared. The NI-TPUreas were characterized by gel permeation chromatography,FTIR, 1 H-NMR, differential scanning calorimetry, thermogravimetric analysis, wide-angle X-ray diffraction, atomic force microscopy,and tensile test. NI-TPUreas exhibited Mn of up to 1.67 × 104 g/mol, initial decomposition temperature over 290 °C, and tensile strength of up to 32 MPa. Several crystallizable NI-TPUreas exhibited Tm exceeding 98 °C. NI-TPUreas with good thermal and mechanical properties were prepared through a green and simple one-pot non-isocyanate route.

关键词： Non-isocyanate route Thermoplastic polyureas One-pot method Sustainable synthesis Transurethane polycondensation

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Frontiers of Computer Science 2020年第1期14卷 191-207页

作者： Huiping LIU Cheqing JIN Aoying ZHOU School of Data Science and Engineering School of Computer Science and Software EngineeringEast China Normal UniversityShanghai 200062China

With the increasing number of GPS-equipped vehicles,more and more trajectories are generated continuously,based on which some urban applications become feasible,such as route *** general,popular route that has been travelled frequently is a good choice,especially for people who are not familiar with the road ***,accurate estimation of the travel cost(such as travel time,travel fee and fuel consumption)will benefit a wellscheduled trip *** this paper,we address this issue by finding the popular route with travel cost *** this end,we design a system consists of three main ***,we propose a novel structure,called popular traverse graph where each node is a popular location and each edge is a popular route between locations,to summarize historical trajectories without road network ***,we propose a self-adaptive method to model the travel cost on each popular route at different time interval,so that each time interval has a stable travel ***,based on the graph,given a query consists of source,destination and leaving time,we devise an efficient route planning algorithmwhich considers optimal route concatenation to search the popular route from source to destination at the leaving time with accurate travel cost ***,we conduct comprehensive experiments and implement our system by a mobile App,the results show that our method is both effective and efficient.

关键词： location-based services route planning travel cost estimation minimum description length optimal road concatenation

Multi-functional supramolecular polymer produced from natural small molecules in a facile route

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Science China Chemistry 2019年第2期62卷 155-156页

作者： Shaobo Ji Huaping Xu Key Lab of Organic Optoelectronics & Molecular Engineering Department of Chemistry Tsinghua University

Polymeric materials are important substrates for the realization of different *** the rapid progress, there are still two big challenges in this field:(1)how to fabricate the materials in a simplified procedure and (2)how to achieve both sophisticated properties and integrated functions in one *** address these problems,Qu, Feringa and Tian et al.[1]recently reported a novel multifunctional supramolecular polymer system synthesized from simple commercial small molecules via a very easy and mild route.

关键词： Polymeric functions mild route

On conservation and development of architecture and environment in the construction of large-scale national infrastructure——Exemplified by the Jiangsu Section of the Eastern route South-to-North Water Diversion Project

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Science China(Technological Sciences) 2009年第12期52卷 3613-3625页

作者： DUAN Jin ,LUO JianLi,WANG XingPing,TANG Jun&YU Gang School of Architecture,Southeast University,Nanjing 210096,China School of Architecture Southeast University Nanjing China

The water-diverting route project’s characteristics,natural landscapes,and histories and humanism of the Jiangsu Section of the Eastern route South-to-North Water Diversion Project were systemically analyzed through proposing and studying the canal culture routes,the water resources heritage corridors,the landscape and recreation corridors,and the town economic *** station areas along the water-diverting route were scientifically zoned and graded through quantitative and qualitative synthetic *** planning compendiums and construction controlling methods were proposed based on the project grades of points,lines,and *** and development of architecture and environment in the large-scale national infrastructure construction were explored *** and methods of developing harmonious water-supplying functions,ecological functions,landscape effects,and cultural effects of large-scale water resources were examined.

关键词： Jiangsu Section of Eastern route South-to-North Water Diversion Project canal culture routes water resources heritage corridors landscape and recreation corridors town economic corridors synthetical zoning and grading

Energy Efficient Constrained Shortest Path First-Based Joint Resource Allocation and route Selection for Multi-Hop CRNs

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China Communications 2017年第12期14卷 72-86页

作者： Qianbin Chen Ling Wang Yuanpeng Gao Rong Chai Xiaoge Huang Key Lab of Mobile Communication Technology Chongqing University of Posts and Telecommunications Chongqing 400065 China

Cognitive radio networks(CRNs) are expected to improve spectrum utilization efficiently by allowing secondary users(SUs) to opportunistically access the licensed spectrum of primary users(PUs).In CRNs,source and destination SUs may achieve information interaction in an ad hoc *** the case that no direct transmission link between the SU transmission pairs is available,multi-hop relay SUs can be applied to forward information for the source and destination SUs,resulting in multi-hop *** this paper,we consider a multi-hop CRN consisting of multiple PUs,SU transmission pairs and relay *** the importance of transmission hops and the tradeoff between data rate and power consumption,we propose an energy efficient constrained shortest path first(CSPF)-based joint resource allocation and route selection algorithm,which consists of two sub-algorithms,i.e.,CSPF-based route selection sub-algorithm and energy efficient resource allocation *** specifically,we first apply CSPF-based route selection sub-algorithm to obtain the shortest candidate routes(SCRs) between the SU pair under the transmission ***,an energy efficient resource allocation problem of the SCRs is formulated and solved by applying iterative algorithm and Lagrange dual ***-lation results demonstrate the effectiveness of the proposed algorithm.

关键词： cognitive radio network multi-hop relay resource allocation route selection energy efficiency

A Flexible Multi-Layer Map Model Designed for Lane-Level route Planning in Autonomous Vehicles

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Engineering 2019年第2期5卷 305-318页

作者： Kun Jiang Diange Yang Chaoran Liu Tao Zhang Zhongyang Xiao State Key Laboratory of Automotive Safety and Energy Department of Automotive Engineering & Collaborative Innovation Center of Intelligent New Energy Vehicles Tsinghua University Beijing 100084 China

An increasing number of drivers are relying on digital map navigation systems in vehicles or mobile phones to select optimal driving routes in order to save time and improve safety. In the near future, digital map navigation systems are expected to play more important roles in transportation systems. In order to extend current navigation systems to more applications, two fundamental problems must be resolved: the lane-level map model and lane-level route planning. This study proposes solutions to both problems. The current limitation of the lane-level map model is not its accuracy but its flexibility;this study proposes a novel seven-layer map structure, called as Tsinghua map model, which is able to support autonomous driving in a flexible and efficient way. For lane-level route planning, we propose a hierarchical route-searching algorithm to accelerate the planning process, even in the presence of complicated lane networks. In addition, we model the travel costs allocated for lane-level road networks by analyzing vehicle maneuvers in traversing lanes, changing lanes, and turning at intersections. Tests were performed on both a grid network and a real lane-level road network to demonstrate the validity and efficiency of the proposed algorithm.

关键词： Lane-level route planning Tsinghua map model Travel cost model

Authenticating QoS-Guaranteed Multicast route Discovery for Ad hoc Networks

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China Communications 2007年第1期4卷 48-55页

作者： Mingxi, Yang Layuan, Li Yiwei, Fang Wuhan Univ Technol Sch Comp Sci & Tech Wuhan 430070 Peoples R China Huazhong Univ Sci & Technol Dept Elect & Inf Eng Wuhan 430074 Peoples R China

This paper presents SEQMRAN,a novel secure efficient QoS multicast route discovery protocol for mobile ad hoc *** protocol relies entirely on one-time signature mechanism,HORSEI,with very efficient signing and verifying,and we do this by improving the HORSE protocol through the introduction of intermediate hash *** main purpose of SEQMRAN is to provide source authentication for QoS multicast routing discovery messages in MANET by constructing multicast tree with QoS and authentication constrains in mobile ad hoc *** performance measure of SEQMRAN is evaluated using network simulator *** results represent that SEQMRAN produces less end-to -end packet latency than RSA public key encryption based secure routing scheme,and it is a feasible approach to securing multicast routing with multiple QoS constrains for mobile ad hoc networks.

关键词： ad hoc maodv QoS security route

route designs and cost estimation for Japan-Russia and Japan-South Korea interconnections

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Global Energy Interconnection 2019年第2期2卷 133-142页

作者： Shota Ichimura Ryo Omatsu Renewable Energy Institute

This paper describes route designs and cost estimation for possible interconnections between Japan-Russia and between Japan-South Korea based on the Asia International Grid Connection Study Group 2^(nd) report. The Group has conducted a desktop study to design several cable routes as possible options. To optimize the route, the group studied a wide range of open data, regarding sea depth, fishery zones, geographic condition, available transmission capacity in connecting points inside Japan and so on. The result of desktop study shows that it is possible to keep sea depth for planned routes less than 300 m and length for most of designed routes is less than 600 km. Compare to existing undersea cables in Europe, proposed routes are not challenging from technical and geological *** study shows that investment cost range, including cost for grid enhancement inside Japan, is from around 200 bn JPY to 600 bn JPY, depending on the routes. Annualized cost range is from around 8 to 24 bn JPY(for 25-year operation), which is not so large compare to 1800 bn JPY-average annual investment in transmission infrastructure by 10 power utilities in the past 23 years.

关键词： Interconnector Undersea cable Grid Cable route AC/DC Converter Japan Russia South Korea.