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Spatiotemporal Prediction of Urban Traffics Based on Deep GNN

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Computers, Materials & Continua 2024年第1期78卷 265-282页

作者： Ming Luo Huili Dou ning zheng School of Computer Science Hangzhou Dianzi UniversityHangzhou310018China Zhejiang Institute of Communications Hangzhou310012China School of Cyberspace Security Hangzhou Dianzi UniversityHangzhou310018China

Traffic prediction already plays a significant role in applications like traffic planning and urban management,but it is still difficult to capture the highly non-linear and complicated spatiotemporal correlations of traffic *** well as to fulfil both long-termand short-termprediction objectives,a better representation of the temporal dependency and global spatial correlation of traffic data is *** order to do this,the Spatiotemporal Graph Neural Network(S-GNN)is proposed in this research as amethod for traffic *** S-GNN simultaneously accepts various traffic data as inputs and investigates the non-linear correlations between the *** terms of modelling,the road network is initially represented as a spatiotemporal directed graph,with the features of the samples at the time step being captured by a convolution *** order to assign varying attention weights to various adjacent area nodes of the target node,the adjacent areas information of nodes in the road network is then aggregated using a graph *** data is output using a fully connected layer at the *** findings show that S-GNN can improve short-and long-term traffic prediction accuracy to a greater extent;in comparison to the control model,the RMSE of S-GNN is reduced by about 0.571 to 9.288 and the MAE(Mean Absolute Error)by about 0.314 to *** experimental results on two real datasets,Pe MSD7(M)and PEMS-BAY,also support this claim.

关键词： Urban traffic traffic temporal correlation GNN prediction

Asymptotic Estimates to Non-global Solutions of a Multi-coupled Parabolic System

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Acta Mathematica Sinica,English Series 2008年第10期24卷 1713-1726页

作者： Rui Hong JI Si ning zheng Department of Applied Mathematics Dalian University of Technology Dalian 116024 P. R. China

This paper deals with asymptotic behavior of solutions to a parabolic system, where two heat equations with inner absorptions are multi-coupled via inner sources and boundary flux. We determine four kinds of simultaneous blow-up rates under different dominations of nonlinearities in the model. Two characteristic algebraic systems associated with the problem are introduced to get very simple descriptions for the four simultaneous blow-up rates as well as the known critical exponents, respectively. It is observed that the blow-up rates are independent of the nonlinear inner absorptions.

关键词： simultaneous blow-up rates asymptotic estimates characteristic algebraic system multicoupled parabolic system non-global solution critical exponent

Preliminary discussion on the ignition mechanism of exploding foil initiators igniting boron potassium nitrate

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Defence Technology（防务技术） 2024年第2期32卷 222-231页

作者： Haotian Jian Guoqiang zheng Lejian Chen zheng ning Guofu Yin Peng Zhu Ruiqi Shen School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Micro-Nano Energetic Devices Key Laboratory of MIIT Nanjing University of Science and TechnologyNanjing 210094China Anhui Province Key Laboratory of Microsystem the 43rd Research Institute of CETCHefei 230088China Science and Technology on Applied Physical and Chemistry Laboratory Shanxi Applied Physics and Chemistry Research Institute Xi'an 710061China

Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting *** solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting *** oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma *** results of the electric characteristics and the impact pressure were inconsistent with ignition *** only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating ***,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this *** HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric *** longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.

关键词： Exploding foil initiator PDV Plasma spectrum Ignition mechanism Boron potassium nitrate

Non-simultaneous quenching for a slow diffusion system coupled at the boundary

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Applied Mathematics(A Journal of Chinese Universities) 2012年第2期27卷 139-149页

作者： QU Cheng-yuan WANG Wei zheng Si-ning School of Science East China Institute of TechnologyNanchang 330013China School of Mathematical Sciences Dalian University of TechnologyDalian 116024China

This paper deals with the quenching behavior of positive solutions to the Newton filtration equations coupled with boundary *** determine quenching rates for non-simultaneous quenching at first,and then establish the ... 详细信息

关键词： quenching nonsimultaneous quenching quenching set slow diffusion nonlinear boundary flux.

Self-optimized single-nanowire photoluminescence thermometry

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Light(Science & Applications) 2023年第2期12卷 259-271页

作者： Zhang Liang Jinhua Wu Ying Cui Hao Sun Cun-zheng ning Department of Electronic Engineering Tsinghua University100084 BeijingChina College of Integrated Circuits and Optoelectronic Chips Shenzhen Technology University518118 ShenzhenGuangdongChina

Nanomaterials-based photoluminescence thermometry(PLT)is a new contact-free photonic approach for temperature sensing,important for applications ranging from quantum technology to biomedical imaging and *** though numerous new materials have been explored,great challenges and deficiencies remain that hamper many *** contrast to most of the existing approaches that use large ensembles of rare-earth-doped nanomaterials with large volumes and unavoidable inhomogeneity,we demonstrate the ultimate size reduction and simplicity of PLT by using only a single erbium-chloride-silicate(ECS)***,we propose and demonstrate a novel strategy that contains a self-optimization or "smart"procedure to automatically identify the best PL intensity ratio for temperature *** automated procedure is used to self-optimize key sensing metrics,such as sensitivity,precision,or resolution to achieve an all-around superior PLT including several record-setting metrics including the first sensitivity exceeding 100%K^(-1)(~138%K^(-1)),the highest resolution of 0.01 K,and the largest range of sensible temperatures 4-500 K operating completely within 1500-1800 nm(an important biological window).The high-quality ECS nanowire enables the use of well-resolved Stark-sublevels to construct a series of PL intensity ratios for optimization in infrared,allowing the completely Boltzmann-based sensing at cryogenic temperature for the frst *** single-nanowire PLT and the proposed optimization strategy overcome many existing challenges and could fundamentally impact PL nano-thermometry and related applications such as single-cell thermometry.

关键词： optimization exceeding simplicity

Wearable and humidity-resistant biomaterials-based triboelectric nanogenerator for high entropy energy harvesting and self-powered sensing

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Nano Research 2022年第7期15卷 6213-6219页

作者： ning zheng Jiehui Xue Yang Jie Xia Cao Zhong Lin Wang CAS Center for Excellence in Nanoscience Beijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100083China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China School of Resources Environment and Materials Guangxi UniversityNanning 530004China Research Center for Bioengineering and Sensing Technology Beijing Key Laboratory for Bioengineering and Sensing technologySchool of Chemistry and Biological engineeringand Beijing Municipal Key Laboratory of New Energy Materials and TechnologiesUniversity of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGeorgia 30332USA

Triboelectric nanogenerator(TENG)provides a new solution to the energy supply by harvesting high entropy ***,wearable electronic devices have high requirements for flexible,humidity-resistant,and low-cost ***,environmentfriendly and multi-functional wheat starch TENG(S-TENG)was made by a simple and green *** open-circuit voltage and short-circuit current of S-TENG are 151.4 V and 47.1μA,respectively.S-TENG can be used not only to drive and intelligently control electronic equipment,but also to effectively harvest energy from body movements and *** addition,the output of S-TENG was not negatively affected with the increase in environmental humidity,but increased *** the range of 20%RH–80%RH,S-TENG can be potentially used as a sensitive self-powered humidity *** S-TENG paves the way for large-scale preparation of multi-functional biomaterials-based TENG,and practical application of self-powered sensing and wearable devices.

关键词： triboelectric nanogenerator natural polymers humidity-resistant wearable smart device self-powered sensing

Fujita Type Conditions to Heat Equation with Variable Source

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 63-68页

作者： Yun-xia LIU Yun-hua WANG Si-ning zheng School of Mathematical Sciences Dalian University of Technology School of Mathematical Sciences Harbin Normal University

This paper studies heat equation with variable exponent ut = △u ＋ Up（x） 4- Uq in RN × （0, T）, where p（x） is a nonnegative continuous, bounded function, 0 〈 p- = infp（x） ≤ p（x） ≤ supp（x） = p＋. It is easy to understand for the problem that all nontrivial nonnegative solutions must be global if and only if max{p＋,q} ≤1. Based on the interaction between the two sources with fixed and variable exponents in the model, some Fujita type conditions are determined that that all nontrivial nonnegative solutions blow up in finite time if 0 〈 q ≤ 1 with p＋〉 1, or 1 〈 q 〈 1 ＋2/N. In addition, if q 〉 1 ＋2/N, then （i） all solutions blow up in finite time with 0 〈 p- ≤ p＋ ≤ 1 ＋2/N; （ii） there are both global and nonglobal solutions for p- ≤ 1 ＋ 2/N; and （iii） there are functions p（x） such that all solutions blow up in finite time, and also functions p（x） such that the problem possesses global solutions when p＋〈 1＋2/N 〈 p＋.

关键词： variable source Fujita type condition heat equation global solutions blow-up

SGCS-made ultrafine CaO/Al_2O_3 sorbent for cyclic CO_2 capture

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Chinese Chemical Letters 2011年第5期22卷 615-618页

作者： Cong Luo Ying zheng ning Ding Qi Long Wu Chu Guang zheng State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China

Multi-cyclic CaO carbonation/calcination is an attractive method for CO_2 capture during coal ***,the capture capacity of CaO sharply decreases with increasing carbonation/calcination *** order to improve the stability of CO_2 capture capacity of CaO during carbonation/calcination cycles,synthetic CaO/Al_2O_3 sorbents were synthesized by two methods：wet chemistry and sol-gel-combustion-synthesis（SGCS） to make a further *** results indicate that the SGCS-made CaO/ Al_2O_3 = 80：20 wt%sorbent provides a competitive performance of a capture capacity of 0.43 g-CO_2/g-sorbent after 20 cycles.

关键词： CO_2 capture CaO Carbonation/calcination cycles SGCS

Physical Performance of Migrant Schoolchildren with Marginal and Severe Iron Deficiency in the Suburbs of Beijing

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Biomedical and Environmental Sciences 2009年第4期22卷 333-339页

作者： JIE WANG JUN-SHENG HUO JING SUN zheng-XIANG ning College of Light Industry and Food Sciences South China University of Technology Guangzhou 510641 Guangdong China Institute of Nutrition and Food Safty Chinese Center for Disease Control and Prevention Beijing 100050 China

Objectives To investigate relationship between iron deficiency of different degrees and physical performance and habitual activity of migrant schoolchildren at the age of 11-14 years. Methods Ninety one randomly selected schoolchildren were divided into three groups according to their iron status. Iron status including hemoglobin （Hb）, serum ferritin （SF）, serum iron （SI） and sTfR was determined. Physical performance tests included maximum oxygen consumption （VO2max） and maximum work time. Energy expenditure （EE） and daily physical activity were estimated by recording 24-h heart rate （HR）. Dietary intake was assessed with frequency questionnaires, and physical activity level was estimated with frequency and physical activity questionnaires. Results Severe iron deficiency （IDA） impaired the aerobic capacity and habitual physical activity. When fat-free mass （FFM） was considered, VO2max （VO2max/FFM） was significantly lower in the iron-marginal group than in the iron-adequate groups among girls （P=0.02）, but such a deference was not found among boys （P=0.28）. Aerobic activity and EE at leisure were significantly lower in the severe iron deficient group than in the marginal iron deficient and iron adequate groups. Net HR at leisure time was correlated with lib, log SF, body weight, and FFM （P〈0.05）. Conclusion The functional effect of iron deficiency on physical performance and habitual physical activity rely on the degree of current iron deficiency. Severe iron deficiency significantly impairs both aerobic capacity and habitual physical activity. Iron-marginal deficiency impairs VO2max/FFM in girls, rather than in boys.

关键词： Iron deficiency anemia Iron deficiency Maximum oxygen consumption Heart rate Energy expenditure Physicalactivity Children of migrant workers