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Precedence-constrained path planning of messenger UAV for air-ground coordination

Control Theory and Technology 2019年第1期17卷 13-23页

作者： Yulong ding Bin XIN jie CHEN School of Automation Beijing Institute of Technology Beijing 700087 China Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Beijing 100081 China Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Technology Beijing 100081 China

This paper addresses an unmanned aerial vehicle (UAV) path planning problem for a team of cooperating heterogeneous vehicles composed of one UAV and multiple unmanned ground vehicles (UGVs). The UGVs are used as mobile actuators and scattered in a large area. To achieve multi-UGV communication and collaboration, the UAV serves as a messenger to fly over all task points to collect the task information and then flies all UGVs to transmit the information about tasks and UGVs. The path planning of messenger UAV is formulated as a precedence-constrained dynamic Dubins traveling salesman problem with neighborhood (PDDTSPN). The goal of this problem is to find the shortest route enabling the UAV to fly over all task points and deliver information to all requested UGVs. When solving this path planning problem, a decoupling strategy is proposed to sequentially and rapidly determine the access sequence in which the UAV visits task points and UGVs as well as the access location of UAV in the com mu nication n eighborhood of each task point and each UGV. The effectiveness of the proposed approach is corroborated through computational experiments on randomly generated instances. The computational results on both small and large in stances dem on strate that the proposed approach can generate high-quality solutions in a reasonable time as compared with two other heuristic algorithms.

关键词： Air-ground coordination curvature-constrained path planningz precedence constraints Dubins traveling salesman problem

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Realizing Enveloping Algebras via Varieties of Modules

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Acta Mathematica Sinica,English Series 2010年第1期26卷 29-48页

作者： Ming ding jie XIAO Fan XU Department of Mathematics Tsinghua University Beijing 100084~ P. R~ China

By using the Ringel-Hall algebra approach, we investigate the structure of the Lie algebra L（A） generated by indecomposable constructible sets in the varieties of modules for any finite- dimensional C-algebra A. We obtain a geometric realization of the universal enveloping algebra R（A） of L（A）, this generalizes the main result of Riedtmann. We also obtain Green＇s formula in a geometric form for any finite-dimensional C-algebra A and use it to give the comultiplication formula in R（A）.

关键词： Ringel-Hall algebra constructible set variety universal enveloping algebra

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Fast Growth Entire Functions Whose Escaping Set Has Hausdorff Dimension Two

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Chinese Annals of Mathematics,Series B 2019年第4期40卷 481-494页

作者： jie ding Jun WANG Zhuan YE School of Mathematics Taiyuan University of TechnologyTaiyuan 030024China School of Mathematics Fudan UniversityShanghai 200433China Department of Mathematics and Statistics Univeristy of North Carolina WilmingtonWilmingtonNC 28403USA

The authors study a family of transcendental entire functions which lie outside the Eremenko-Lyubich class in general and are of infinity growth order. Most importantly,the authors show that the intersection of Julia set and escaping set of these entire functions has full Hausdorff dimension. As a by-product of the result, the authors also obtain the Hausdorff measure of their escaping set is infinity.

关键词： Dynamic systems Entire function Julia set Escaping set Hausdorff dimension

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A Cooperative MIMO Transmission Scheme for Cluster-based Wireless Sensor Networks

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China Communications 2010年第5期7卷 14-22页

作者： ding jie Liu Danpu Wu Huari Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 P. R. China Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 P. R. China

Wireless sensor network is becoming more and more popular in recent years, but energy- constrained characteristic of sensor nodes is one of the critical issues that we must consider in system design. In this paper, a cluster-based virtual VBLAST transmission scheme is proposed to achieve energy savings for energy-constrained wireless sensor networks. In the proposed scheme, instead of using cluster member as cooperative nodes, multiple cluster heads cooperate to form virtual antenna array so that V-BLAST based virtual MIMO transmission can be implemented. Based on the communication energy consumption model, a way to optimize the parameters for the scheme is given. In addition, detailed simulation is performed to evaluate the performance of the proposed scheme for both densely and sparsely deployed sensor networks. Theoretical analysis and simulation results verify the energy efficiency of the proposed scheme.

关键词： energy efficiency virtual MIMO VBLAST cluster wireless sensor networks

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Clinical study on Hypotony following blunt ocular trauma

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International Journal of Ophthalmology(English edition) 2012年第6期5卷 771-773页

作者： chun ding Jun Zeng Department of Ophthalmology the Second Xiangya Hospital of Central South University and Institution of Ophthalmic Center

AIM: To evaluate the incidence and risk factors of hypotony in patients with blunt ocular trauma. METHODS: The medical records of 145 patients with blunt ocular trauma were reviewed. Hypotony was defined as an average intraocular pressure (IOP) of 5mmHg or less for three times. RESULTS: Among these 145 patients, hypotony was noted in 10 (6.9%) patients. The rate of hypotony in patients with ciliochoroidal detachment was 66.7% (2 out of 3 eyes), and 5.6% (8 out of 142 eyes) in patients without ciliochoroidal detachment,the difference was statistically significant (P=0.003). The rate of hypotony in patients with traumatic retinal detachment was 18.5% (5 out of 27 eyes), and 4.2% (5 out of 118 eyes) in patients without traumatic retinal detachment, the difference was statistically significant (P=0.026). The rate of hypotony in the patients with anterior proliferative vitreoretinopathy was 42.9% (3 out of 7 eyes) and 5.1% (7 out of 138 eyes) in the patients without anterior proliferative vitreoretinopathy, the difference was statistically significant(P=0.002). CONCLUSION: Ocular hypotension is a complication of blunt ocular trauma. The risk factors include ciliochoroidal detachment, traumatic retinal detachment, and anterior proliferative vitreoretinopathy.

关键词： hypotony blunt trauma anterior proliferative vitreoretinopathy ciliochoroidal detachment traumatic retinal detachment

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Protonation Effect on One- and Two-photon Absorption Property of a Newly Synthesized Octupolar Chromophore

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Chinese Journal of Chemical Physics 2012年第6期25卷 666-670,I0003页

作者： Hong-iuan ding jie Sun Chuan-kui Wang College of Physics and Electronics Shandong Normal University Ji'nan 250014 China

The protonation effects on one- and two-photon absorption properties of an octupolar molecule TA with 1,3,5-triazine core and pyrrole electron-donating end-groups have been studied at hybrid density functional theory level. A computational scheme is developed to simulate a proton attached to an atom. The numerical results show that large changes in both one- and two-photon absorption properties are observed when the compound is transformed from neutral to threefold protonated states. When the compound is protonated, more charge transfer states appear and the absorption band has a red-shift. Furthermore, the two-photon absorption cross-section is largely enhanced. The theoretical calculations demonstrate the protonation effect on promoting the intramolecular charge transfer strength. The results present qualitative agreement with the experimental observations. A two-photon absorption switch with the compound TA based on the protonation effect is proposed.

关键词： Protonation Two-photon absorption Response theory Octupolar chro-mophore

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Spectral Properties and Solubilization Location of 2′-Ethylhexyl 4-（N,N-Dimethylamino）benzoate in Micelles

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Chinese Journal of Chemical Physics 2008年第2期21卷 163-168页

作者： Ning ding Xin-zhen Du chun Wang Xiao-quan Lu College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

Dual fluorescence and UV absorption of 2′-ethylhexyl 4-（N,N-dimethylamino）benzoate （EHDMAB） were investigated in cationic, non-ionic and anionic micelles. When EHDMAB was solubilized in different micelles, the UV absorption of EHDMAB was enhanced. Twisted intramolecular charge transfer （TICT） emission with longer wavelength was observed in ionic micelles, whereas TICT emission with shorter wavelength was obtained in non-ionic micelles. In particular, dual fluorescence of EHDMAB was significantly quenched by the positively charged pyridinium ions arranged in the Stern layer of cationic micelles. UV radiation absorbed mainly decays via TICT emission and radiationless deactivation. The dimethylamino group of EHDMAB experiences different polar environments in ionic and non-ionic micelles according to the polarity dependence of TICT emission of EHDMAB in organic solvents. In terms of the molecular structures and sizes of EHDMAB and surfactants, each individual EHDMAB molecule should be buried in micelles with its dimethylamino group toward the polar head groups of different micelles and with its 2′-ethylhexyl chain toward the hydrophobic micellar core. Dynamic fluorescence quenching measurements of EHDMAB provide further support for the location of EHDMAB in different micelles.

关键词： Dual fluorescence Twisted intramolecular charge transfer UV absorption Surfactant 2′-Ethylhexyl 4-(N N-dimethylamino)benzoate Sunscreen

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Temperature of intermediate mass fragments in simulated ^(40)Ca + ^(40)Ca reactions around the Fermi energies by AMD model

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Nuclear Science and Techniques 2016年第5期27卷 146-151页

作者： chun-Wang Ma chun-Yuan Qiao Tian-Tian ding Yi-Dan Song Institute of Particle and Nuclear Physics Henan Normal University

The primary fragments in ^(40)Ca +^(40)Ca reactions at 35,50,80,100,140,and 300 MeV/u were simulated using the antisymmetrized molecular dynamics model,in the phase space at t=300 fm/c with a coalescence radius R_c=5 *** standard Gogny interactions g0,g0 as,and gOass were adopted in simulating the collisions at an impact parameter of b=0 *** was found,using an isobaric yield ratio method,that temperature of the primary fragment depends on the incident energy and hardness of the interaction *** temperature obtained in this work agrees with the results by the self-consistent fitting method.

关键词：模型模拟中等质量碎片温度 MD模型 Ca 反应费米能分子动力学

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Context-Based Moving Object Trajectory Uncertainty Reduction and Ranking in Road Network

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Journal of Computer Science & Technology 2016年第1期31卷 167-184页

作者： Jian Dai Zhi-Ming ding Jia-jie Xu School of Computer Science Beijing University of Technology Beijing 100124 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Software Chinese Academy of Sciences Beijing 100190 China School of Computer Science and Technology Soochow University Suzhou 215000 China

To support a large amount of GPS data generated from various moving objects, the back-end servers usually store low-sampling-rate trajectories. Therefore, no precise position information can be obtained directly from the back-end servers and uncertainty is an inherent characteristic of the spatio-temporal data. How to deal with the uncertainty thus becomes a basic and challenging problem. A lot of researches have been rigidly conducted on the uncertainty of a moving object itself and isolated from the context where it is derived. However, we discover that the uncertainty of moving objects can be efficiently reduced and effectively ranked using the context-aware information. In this paper, we focus on context- aware information and propose an integrated framework, Context-Based Uncertainty Reduction and Ranking （CURR）, to reduce and rank the uncertainty of trajectories. Specifically, given two consecutive samplings, we aim to infer and rank the possible trajectories in accordance with the information extracted from context. Since some context-aware information can be used to reduce the uncertainty while some context-aware information can be used to rank the uncertainty, to leverage them accordingly, CURR naturally consists of two stages： reduction stage and ranking stage which complement each other. We also implement a prototype system to validate the effectiveness of our solution. Extensive experiments are conducted and the evaluation results demonstrate the efficiency and high accuracy of CURR.

关键词： moving object trajectory uncertainty reduction road network context-aware information

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Chemical approaches towards installation of rare functional groups in bacterial surface glycans

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Chinese Journal of Natural Medicines 2022年第6期20卷 401-420页

作者： QIN chun-Jun ding Mei-Ru TIAN Guang-Zong ZOU Xiao-Peng FU Jun-jie HU Jing YIN Jian Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi 214122China Wuxi School of Medicine Jiangnan UniversityWuxi 214122China

Bacterial surface glycans perform a diverse and important set of biological roles,and have been widely used in the treatment of bacterial infectious *** majority of bacterial surface glycans are decorated with diverse rare functional groups,including amido,acetamidino,carboxamido and pyruvate *** functional groups are thought to be important constituents for the biological activities of *** synthesis of glycans bearing these functional groups or their variants is essential for the investigation of structure-activity relationships by a medicinal chemistry *** date,a broad choice of synthetic methods is available for targeting the different rare functional groups in bacterial surface *** article reviews the structures of naturally occurring rare functional groups in bacterial surface glycans,and the chemical methods used for installation of these groups.

关键词： Bacterial surface glycan Chemical synthesis Amido group Acetamidino group Carboxamido group Pyruvyl ketal

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