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Resource allocation and hybrid prediction scheme for low-latency visual feedbacks to support tactile Internet multimodal perceptions

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The Journal of China Universities of Posts and Telecommunications 2021年第4期28卷 13-28页

作者： kang Mancong Li Xi Ji hong Zhang Heli School of Telecommunication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Predicting user states in future and rendering visual feedbacks accordingly can effectively reduce the visual experienced delay in the tactile Internet(TI). However, most works omit the fact that different parts in an image may have distinct prediction requirements, based on which different prediction models can be used in the predicting process, and then it can further improve predicting quality especially under resources-limited environment. In this paper, a hybrid prediction scheme is proposed for the visual feedbacks in a typical TI scenario with mixed visuo-haptic interactions, in which haptic traffic needs sufficient wireless resources to meet its stringent communication requirement, leaving less radio resources for the visual feedback. First, the minimum required number of radio resources for haptic traffic is derived based on the haptic communication requirements, and wireless resources are allocated to the haptic and visual traffics afterwards. Then, a grouping strategy is designed based on the deep neural network(DNN) to allocate different parts from an image feedback into two groups to use different prediction models, which jointly considers the prediction deviation thresholds, latency and reliability requirements, and the bit sizes of different image parts. Simulations show that, the hybrid prediction scheme can further reduce the visual experienced delay under haptic traffic requirements compared with existing strategies.

关键词： tactile Internet ultra-reliable and low-latency communications enhanced mobile broadband visuo-haptic feedbacks layered rendering

Impulsive synchronization of a nonlinear coupled complex network with a delay node

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Chinese Physics B 2012年第1期21卷 133-139页

作者： Sun Wen Chen Zhong kang Yu-hong School of Information and Mathematics Yangtze UniversityJingzhou 434023China School of Foreign Studies Yangtze UniversityJingzhou 434023China

We investigate the impulsive synchronization of a nonlinear coupled complex network with a delay node. Both delay coupling and non-delay coupling, as well as the symmetrical coupling matrix and the asymmetrical coupling matrix are considered. Based on the comparison theorem of an impulsive differential system, some novel synchronization criteria are derived. Finally, numerical simulations demonstrate the effectiveness of the proposed synchronization criteria.

关键词： complex network impulsive control synchronization nonlinear coupled

Distributed Edge Cooperation and Data Collection for Digital Twins of Wide-Areas

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China Communications 2023年第8期20卷 177-197页

作者： Mancong kang Xi Li hong Ji Heli Zhang Key Laboratory of Universal Wireless Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

Digital twins for wide-areas(DT-WA)can model and predict the physical world with high fidelity by incorporating an artificial intelligence(AI)***,the AI model requires an energy-consuming updating process to keep pace with the dynamic environment,where studies are still in *** reduce the updating energy,this paper proposes a distributed edge cooperation and data collection *** AI model is partitioned into multiple sub-models deployed on different edge servers(ESs)co-located with access points across wide-area,to update distributively using local sensor *** reduce the updating energy,ESs can choose to become either updating helpers or recipients of their neighboring ESs,based on sensor quantities and basic updating *** would share their updated sub-model parameters with neighboring recipients,so as to reduce the latter updating *** minimize system energy under updating convergency and latency constraints,we further propose an algorithm to let ESs distributively optimize their cooperation identities,collect sensor data,and allocate wireless and computing *** comprises several constraint-release approaches,where two child optimization problems are solved,and designs a largescale multi-agent deep reinforcement learning *** shows that the proposed scheme can efficiently reduce updating energy compared with the baselines.

关键词： digital twin smart city multi-agent deep reinforcement learning resource allocation

Influence of Re-Ti modification on the high impact wear resistance of high Si bainitic cast steel

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 756-762页

作者： Jin-feng Huang hong-sheng Fang Yan-kang Zheng State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijnig 100083 China Department of Materials Science and Engineering Tsinghna University Beijing 100084 China

The effect of rare earth （Re） and titanium （Ti） multi-modification on the impact wear behavior of Mn-B high-Si bainitic cast steel was investigated systematically. The experiments show that the impact wear resistance can be improved greatly with the addition of Re and Ti. Its wear loss is only about 1/3-1/2 as large as that of the unmodified bainitic cast steel. By the Re/Ti modification, coarse dendrite grains and bainitic/martensite duplex structure have been refined effectively, and the impact toughness of the bainitic cast steel is nearly tripled （10 mm×10 mm×55 mm, with unnotched sample）. Consequently, the modified bainitic cast steel possesses good wear resistance under high im- pact. For both modified and unmodified bainitic cast steels, high hardness white layer and deformed zone are developed beneath the worn surface under the high impact wear, but the formation and propagation of cracks are different for these bainitic casting steels. Different mod- els for the formation and propagation of cracks for both modified and unmodified bainitic cast steels under high impact wear are proposed.

关键词： cast steel modification grain refmement impact wear spalling

Ethylene Polymerization and Copolymerization with Polar Monomers by Benzothiophene-bridged BPMO-Pd Catalysts

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Chinese Journal of Polymer Science 2020年第6期38卷 579-586页

作者： hong-Liang Mu Jun-Hao Ye Guang-Lin Zhou kang-kang Li Zhong-Bao Jian State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

A series of new bisphosphine-monoxide(BPMO)ligands based on benzothiophene backbone and the corresponding palladium complexes{k2-P(O)(Ph)2-3-PR1R2-C8H4S}PdMeCl{2a:R1=R2=Ph;2b:R1=R2=2-0Me-Ph;2c:R1=R2=2-CF3-Ph;2d:Rl=Ph,R2=2-(2',6'-(OMe)2C6Hz)-C6H4}were synthesized and fully characterized by1H-,13C-,31P-,and 2D-NMR spectroscopy and single-crystal X-ray *** the presence of Na+B[3,5-(CF3)2C6H3]4(NaBArF),these complexes showed very high activities(up to 2.0 x 10’g-mol-1.h-)for ethylene *** significantly,these catalysts enabled the copolymerization of ethylene with a broad scope of commercially available polar comonomers such as acrylates,acrylic acid,acrylonitrile,vinyltrialkoxysilane,allyl acetate,and long-chain 6-chloro-1-hexene to give functionalized polyethylene with reasonable catalytic activities(up to 105 g-mol-l.h-)and incorporations(up to 5.3 mol96).This contribution suggests that,besides the modulation of conventionally steric and electronic factors,the connectivity(at dfferent linking positions)of BPMO(P,O)donors to the heteroaryl backbone also greatly infuences the catalyst properties in terms of catalytic activity,polymer branching content,comonomer scope,and comonomer incorporation.

关键词： Olefin polymerization Bisphosphine monoxide Plladium Polar monomers Heteroaryl backbone

Optioning Water Rights:A Potential Alternative to the Hanjiang-Weihe River Water Transfer Project,China

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Chinese Geographical Science 2020年第6期30卷 1039-1051页

作者： HE Xiaoying kang hong GU Yaopeng SONG Yuanliang School of Management and Economics Xi'an Technological UniversityXi'an 710021China Zhongguancun Listed Companies Association Beijing 100011China

China has started shifting from relying on supply management to demand management strategy in addressing its water shortage *** option,a financial derivative for water commodity,has been utilized to manage water demands in the United States and Europe since the 1990 s but is still novel to *** this study we analyzed the pros and cons of China’s existing system for water rights transfers and proposed an alternative,flexible trading instrument-water options for *** the uncertainty to water option pricing,this study first conducted an empirical analysis of the water option in the water-receiving area of the Hanjiang-Weihe River Transfer Project of China,and then evaluated the benefits of the water option *** show that water option trading can bring water cost saving and increase the potential industrially added value for industrial enterprises in the receiving area,and trading of short-and-medium term water options is more favorable than the long-term water options *** novel water option trading proposed in this study,once verified through pilot studies,will be helpful in addressing water shortage problems in China.

关键词： water shortage demand management water rights transfer water options water diversion project

Adaptive rotor current control for wind-turbine driven DFIG using resonant controllers in a rotor rotating reference frame

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 149-155页

作者： Jia-bing HU Yi-kang HE hong-sheng WANG School of Electrical Engineering Zhejiang University Hangzhou 310027 China

This paper proposes an adaptive rotor current controller for doubly-fed induction generator (DFIG), which consists of a proportional (P) controller and two harmonic resonant (R) controllers implemented in the rotor rotating reference frame. The two resonant controllers are tuned at slip frequencies ωslip+ and ωslip-, respectively. As a result, the positive- and negative-sequence components of the rotor current are fully regulated by the PR controller without involving the positive- and negative-sequence decomposition, which in effect improves the fault ride-through (FRT) capability of the DFIG-based wind power generation system during the period of large transient grid voltage unbalance. Correctness of the theoretical analysis and feasibility of the proposed unbalanced control scheme are validated by simulation on a 1.5-MW DFIG wind power generation system.

关键词： Unbalanced grid voltage Doubly-fed induction generator (DFIG) Proportional plus Resonant (PR) controller Faultride-through (FRT)

Synthesis and Crystal Structure of 2-Nitrophenyl N,N-Bis(2-chloroethyl)-N'-(4-methylbenzene- sulfonamino)ethyl-phosphorodiamidate

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Chinese Journal of Structural Chemistry 2006年第7期25卷 797-800页

作者： ZHANG Gai-hong CHEN ru-Yu HUANG You MIAO Zhi-Wei Institute and State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China

The crystal structure of 2-nitrophenyl N,N-bis（2-chloroethyl）-N＇-（4-methylbenzene-sulfonamino）ethyl-phosphorodiamidate （C19H25Cl2N4O6PS） was determined by single-crystal X-ray diffraction analysis. The compound crystallizes in the triclinic system, space group PI^- with a = 9.3664（13）, b = 9.9560（14）, c = 13.1803（18） ,A, α = 87.338（2）, β= 87.632（2）, γ = 79.536（2）°, Dc = 1.484 g/cm^3, Z = 2, λ = 0.71073 A, μ（MoKα） = 0.465, Mr = 539.36, V = 1206.7（3） A^3, F（000） = 560, the final R = 0.0426 and wR = 0.1097 for 3463 observed reflections with I 〉 2σ（I）.

关键词： sulfonamide crystal structure phosphorodiamidate

A Mild and Efficient Procedure for the Preparation of Chromone-2-carboxylates

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Chinese Chemical Letters 2006年第8期17卷 1005-1008页

作者： Juan hong YU Yu She YANG ru Yun JI State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Shanghai 201203

A mild and efficient procedure to build up various chromone-2-carboxylates was developed. Condensation of diverse 2-hydroxyacetophones with tetr-butyl oxalate in the presence of sodium ethoxide could be accomplished rapidly under mild condition. Cyclodehydration was carried out to achieve chromone-2-carboxylates in one-pot with impressive yield. Advantages over conventional methods with diethyl oxalate were observed in yield and reaction time.

关键词： Chromone-2-carboxylates tea-butyl ethyl oxalate diethyl oxalate.