检索结果-南通市图书馆

CHARGING STATION PLANNING FOR PLUG-IN ELECTRIC VEHICLES

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2018年第1期27卷 24-45页

作者： zhihong zhu Ziyou Gao Jianfeng Zheng Haoming Du Transportation Management College Dalian Maritime University Dalian China

A novel model for the charging station planning problem of plug-in electric vehicles is proposed in this paper considering the users＇ daily travel. With the objective of minimizing the total cost, including the charging stations＇ cost （including installing cost and management cost） and the users＇ cost （including station access cost and charging cost）, the proposed model simultaneously handles the problems where to locate the charging stations and how many chargers to be established in each charging station. Considering that different users may have different perception of station access cost and charging cost, two cases （i.e., homogeneous users and heterogeneous users） are typically investigated. The impacts of different discount rates, operating period of the charging stations, number of electric vehicles and number of charging stations on the location of the charging station are also studied. The simulation results not only show that it is very important to locate the charging stations according to the traveling behavior of users, but also verify the validity of the proposed model.

关键词： Electric vehicles charging station location problem

Unipolar p-type monolayer WSe_(2) field-effect transistors with high current density and low contact resistance enabled by van der Waals contacts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第11期17卷 10162-10169页

作者： Miaomiao Li Xinyu Zhang Zimei Zhang Gang Peng zhihong zhu Jia Li Shiqiao Qin Mengjian zhu College of Advanced Interdisciplinary Studies & Hunan Provincial Key Laboratory of Novel Nano-optoelectronic Information Materials and Devices National University of Defense Technology Changsha 410073 China Nanhu Laser Laboratory National University of Defense Technology Changsha 410073 China Hunan Key Laboratory of Two-Dimensional Materials and State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China College of Science & Hunan Key Laboratory of Extreme Matter and Applications National University of Defense Technology Changsha 410073 China

High-performance field-effect transistors (FETs) based on atomically thin two-dimensional (2D) semiconductors have demonstrated great promise in post-Moore integrated circuits. However, unipolar p-type 2D semiconductor transistors yet remain challenging and suffer from low saturation current density (less than 10 µA·µm^(−1)) and high contact resistance (larger than 100 kΩ·µm), mainly limited by the Schottky barrier induced by the mismatch of the work-functions and the Fermi level pinning at the metal contact interfaces. Here, we overcome these two obstacles through van der Waals (vdW) integration of high work-function metal palladium (Pd) as the contacts onto monolayer WSe2 grown by chemical vapor deposition (CVD) method. We demonstrate unipolar p-type monolayer WSe2 FETs with superior device performance: room temperature on-state current density exceeding 100 µA·µm^(−1), contact resistance of 12 kΩ·µm, on/off ratio over 107, and field-effect hole mobility of ~ 103 cm2·V^(−1)·s^(−1). Electrical transport measurements reveal that the Fermi level pinning effect is completely effectively eliminated in monolayer WSe2 with vdW Pd contacts, leading to a Schottky barrier-free Ohmic contact at the metal-semiconductor junctions. Combining the advantages of large-scale vdW contact strategy and CVD growth, our results pave the way for wafer-scale fabrication of complementary-metal-oxide-semiconductor (CMOS) logic circuits based on atomically thin 2D semiconductors.

关键词： two-dimensional(2D)field-effect transistors(FETs) monolayer WSe2 van der Waals(vdW)contact on-state current hole mobility

Predicting plant traits and functional types response to grazing in an alpine shrub meadow on the Qinghai-Tibet Plateau

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2012年第5期55卷 837-851页

作者： zhu zhihong WANG XiaoAn LI YingNian WANG Gang GUO Hua Colleee of Life Sciences Shaanxi Normal UniversityXi'an 710062China Northwest Institute of Plateau Biology Chinese Academy of SciencesXining 810008China College of Life Sciences Lanzhou UniversityLanzhou 710000China

The identification of easily measured plant functional types (PFTs) that consistently predict grazing response would be a major *** responses to grazing of individual traits and PFTs were analyzed along a grazing gradient in an alpine shrub meadow on the Qinghai-Tibet Plateau,*** response types were identified;grazing increaser (GI),grazing decreaser (GD),and neutral (NE) for both traits and *** traits were measured:plant height,economic group,cotyledon type,plant inclination,growth form,life cycle,and vegetative *** first five were significantly affected by *** regressions for grazing response of the seven traits showed that the best single predictors of response were growth form (including the attributes "Scattered","Bunched" or "Closely Bunched"),and plant inclination ("Rosette","Prostrate",or "Erect"),followed by economic group ("Shrub","Grass","Sedge","Legume","Forb",or "Harmful") and plant height ("Tall","Medium",or "Small").Within the four optimal traits,the summed dominance ratio (SDR) of small plants,forbs,rosette and bunched plants,invariably increased,while that of tall plants,shrubs,grasses,and erect plants decreased,when grazing pressure was *** correspondence analysis (CCA) identified eleven explanatory PFTs based on 195 defined PFTs,by combining the different attributes of the four optimal *** explanatory PFTs,the most valuable in predicting the community response to grazing were Tall×Shrub×Erect×Scattered and Small×Forb×Rosette,as these have the closest connections with grazing disturbance and include fewer *** richness,diversity,and community evenness,did not differ among grazing treatments because turnover occurred in component species and their relative abundances along the grazing *** have demonstrated that a minimum set of PFTs resulting from optimal individual traits can provide consistent prediction of community responses to grazing in this *** app

关键词： Alpine shrub meadow grazing response optimal traits plant functional types

MnBr_(2)catalyzed regiospecific oxidative Mizoroki-Heck type reaction

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2022年第5期33卷 2391-2396页

作者： Xiang Chen zhihong zhu Shanshan Liu Yi-Hung Chen Xiao Shen Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan UniversityWuhan 430072China

Herein, we report an unprecedented regiospecific oxidative Mizoroki-Heck type reaction for the synthesis of α-difluoromethyl homoallylic alcohols. The reaction shows broad substrate scopes and high functional group tolerance. Late-stage functionalization of complex biologically active molecules demonstrates the synthetic potential of this transformation. Mechanistic study supports the involvement of MnBr_(2) catalyzed radical 1,2-silyl transfer.

关键词： Fluoroalkylation Mizoroki-Heck Mn catalysis Radical 1,2-silyl transfer Homoallylic alcohols

Harmonic reducer in-situ fault diagnosis for industrial robots based on deep learning

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2022年第9期65卷 2116-2126页

作者： ZHOU Xing ZHOU HuiCheng HE YiMing HUANG ShiFeng zhu zhihong CHEN JiHong School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Foshan Institute of Intelligent Equipment Technology Foshan 528234China

The harmonic reducer is an essential kinetic transmission component in the industrial *** is easy to be fatigued and resulted in physical malfunction after a long period of ***,an accurate in-situ fault diagnosis for the harmonic reducers in an industrial robot is especially *** paper proposes a fault diagnosis method based on deep learning for the harmonic reducer of industrial robots via consecutive time-domain vibration *** the sampling signals from industrial robots are long,narrow,and channel-independent,this method combined a 1-dimensional convolutional neural network with matrix kernels(1-D MCNN)adaptive *** adjusting the size of the convolution kernels,it can concentrate on the contextual feature extraction of consecutive time-domain data while retaining the ability to process the multi-channel fusion *** proposed method is examined on a physical industrial robot platform,which has achieved a prediction accuracy of99%.Its performance is appeared to be superior in comparison to the traditional 2-dimensional CNN,deep sparse automatic encoding network(DSAE),multilayer perceptual network(MLP),and support vector machine(SVM).

关键词： harmonic reducer industrial robots fault diagnosis convolutional neural network(CNN)

同方期刊数据库

Solar radiation effects on leaf nitrogen and phosphorus stoichiometry of Chinese fir across subtropical China

在线全文

学校读者我要写书评

暂无评论

Forest Ecosystems 2021年第4期8卷 831-840页

作者： Ran Tong Yini Cao zhihong zhu Chenyang Lou Benzhi Zhou Tonggui Wu Qianjiangyuan Forest Ecosystem Research Station Research Institute of Subtropical ForestryChinese Academy of ForestryHangzhou 311400China East China Coastal Forest Ecosystem Long-term Research Station Research Institute of Subtropical ForestryChinese Academy of ForestryHangzhou 311400China Guangdong Provincial Key Laboratory of Water Quality 313 Improvement and Ecological Restoration for Watersheds Institute of Environmental and Ecological EngineeringGuangdong 314 University of TechnologyGuangzhou 510006China Zhejiang A&F University Hangzhou 311300China

Background:Solar radiation(SR)plays critical roles in plant physiological processes and ecosystems ***,the exploration of SR influences on the biogeochemical cycles of forest ecosystems is still in a slow progress,and has important implications for the understanding of plant adaption strategy under future environmental ***,this research was aimed to explore the influences of SR on plant nutrient characteristics,and provided theoretical basis for introducing SR into the establishment of biochemical models of forest ecosystems in the future ***:We measured leaf nitrogen(N)and phosphorus(P)stoichiometry in 19 Chinese fir plantations across subtropical China by a field *** direct and indirect effects of SR,including global radiation(Global R),direct radiation(Direct R)and diffuse radiation(Diffuse R)on the leaf N and P stoichiometry were ***:The linear regression analysis showed that leaf N concentration had no association with SR,while leaf P concentration and N:P ratio were negatively and positively related to SR,*** least squares path model(PLS-PM)demonstrated that SR(*** R and Diffuse R),as a latent variable,exhibited direct correlations with leaf N and P stoichiometry as well as the indirect correlation mediated by soil P *** direct associations(path coefficient=−0.518)were markedly greater than indirect associations(path coefficient=−0.087).The covariance-based structural equation modeling(CB-SEM)indicated that SR had direct effects on leaf P concentration(path coefficient=−0.481),and weak effects on leaf N *** high SR level elevated two temperature indexes(mean annual temperature,MAT;≥10°C annual accumulated temperature,≥10℃ AAT)and one hydrological index(mean annual evapotranspiration,MAE),but lowered the soil P ***,MAE and soil P content could affect the leaf P concentration,which cause the indirect effect of SR on leaf P concentration(pa

关键词： Solar radiation Leaf Soil Nitrogen and phosphorus Stoichiometry Chinese fir

Electrically-driven ultrafast out-of-equilibrium light emission from hot electrons in suspended graphene/hBN heterostructures

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第1期6卷 328-338页

作者： Qiang Liu Wei Xu Xiaoxi Li Tongyao Zhang Chengbing Qin Fang Luo zhihong zhu Shiqiao Qin Mengjian zhu Kostya S Novoselov College of Advanced Interdisciplinary Studies&Hunan Provincial Key Laboratory of Novel Nano-optoelectronic Information Materials and Devices National University of Defense TechnologyChangshaHunan 410073People’s Republic of China Nanhu Laser Laboratory National University of Defense TechnologyChangshaHunan 410073People’s Republic of China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006People’s Republic of China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006People’s Republic of China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006People’s Republic of China Institute for Functional Intelligent Materials National University of SingaporeSingapore 117544Singapore Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore

Nanoscale light sources with high speed of electrical modulation and low energy consumption are key components for nanophotonics and *** record-high carrier mobility and ultrafast carrier dynamics of graphene make it promising as an atomically thin light emitter which can be further integrated into arbitrary platforms by van der Waals ***,due to the zero bandgap,graphene is difficult to emit light through the interband recombination of carriers like conventional ***,we demonstrate ultrafast thermal light emitters based on suspended graphene/hexagonal boron nitride(Gr/hBN)*** in biased graphene are significantly heated up to 2800 K at modest electric fields,emitting bright photons from the near-infrared to the visible spectral *** eliminating the heat dissipation channel of the substrate,the radiation efficiency of the suspended Gr/hBN device is about two orders of magnitude greater than that of graphene devices supported on SiO2or *** demonstrate that hot electrons and low-energy acoustic phonons in graphene are weakly coupled to each other and are not in full thermal *** cooling ofhigh-temperature hot electrons to low-temperature acoustic phonons is enabled by the significant near-field heat transfer at the highly localized Gr/hBN interface,resulting in ultrafast thermal emission with up to 1 GHz bandwidth under electrical *** is found thatsuspending the Gr/hBN heterostructures on the SiO2trenches significantly modifies the light emission due to the formation of the optical cavity and showed a~440%enhancement inintensity at the peak wavelength of 940 nm compared to the black-body thermal *** demonstration of electrically driven ultrafast light emission from suspended Gr/hBNheterostructures sheds the light on applications of graphene heterostructures in photonicintegrated circuits,such as broadband light sources and ultrafast thermo-optic phase modulat

关键词： suspended graphene ultrafast light emitter van der Waals heterostructures thermal radiation electron–phonon interaction

High performance electro-optic modulator based on thin-film lithium niobate

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2022年第10期18卷 583-587页

作者： LIU Leshu LIU Ning ZHANG Jianfa zhu zhihong LIU Ken College of Advanced Interdisciplinary Studies&Hunan Provincial Key Laboratory of Novel Nano-Optoelectronic Information Materials and Devices National University of Defense TechnologyChangsha410073China

Electro-optic(EO) modulator plays a very critical role in the optical communication systems. Here, we report a stimulated thin-film lithium niobate(LN) modulator with a half-wave voltage-length product of 1.8 V·cm, which can successfully achieve modulation and demodulation of a 1 GHz sinusoidal signal with an amplitude of 5 V in experiment. The optical loss caused by metal electrodes is reduced by optimizing the waveguide structure and depositing silica onto the waveguide, and group-velocity matching and characteristic impedance matching are achieved by optimizing the buffer silica layer and the electrode structure for larger bandwidth, which simultaneously improves the modulation efficiency and bandwidth performance. Our work demonstrated here paves a foundation for integrated photonics.

关键词： modulator waveguide lithium

Optical neural networks:progress and challenges

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第11期13卷 2511-2535页

作者： Tingzhao Fu Jianfa Zhang Run Sun Yuyao Huang Wei Xu Sigang Yang zhihong zhu Hongwei Chen College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangshaChina Hunan Provincial Key Laboratory of Novel Nano-Optoelectronic Information Materials and Devices National University of Defense TechnologyChangshaChina Nanhu Laser Laboratory National University of Defense TechnologyChangshaChina Department of Electronic Engineering Tsinghua UniversityBeijingChina Beijing National Research Center for Information Science and Technology(BNRist) BeijingChina

Artificial intelligence has prevailed in all trades and professions due to the assistance of big data resources,advanced algorithms,and high-performance electronic ***,conventional computing hardware is inefficient at implementing complex tasks,in large part because the memory and processor in its computing architecture are separated,performing insufficiently in computing speed and energy *** recent years,optical neural networks(ONNs)have made a range of research progress in optical computing due to advantages such as subnanosecond latency,low heat dissipation,and high *** are in prospect to provide support regarding computing speed and energy consumption for the further development of artificial intelligence with a novel computing ***,we first introduce the design method and principle of ONNs based on various optical ***,we successively review the non-integrated ONNs consisting of volume optical components and the integrated ONNs composed of on-chip ***,we summarize and discuss the computational density,nonlinearity,scalability,and practical applications of ONNs,and comment on the challenges and perspectives of the ONNs in the future development trends.

关键词： networks neural hardware