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Advances in Atmospheric Sciences 2020年第2期37卷 131-136页

作者： Fuzhong WENG Xinwen yu Yihong DUAN Jun YANG Jianjie wang Chinese Academy of Meteorological Sciences Beijing 100081China Chinese Meteorological Administration Beijing 100081China National Meteorological Satellite Center Beijing 100081China National Meteorological Center Beijing 100081China

*** requirements for developing Feng yun satellite observation operators In the past two decades,satellite measurements have been widely utilized for understanding and predicting weather and climate,and are now an ess... 详细信息

关键词： operators utilized Operator

DESIGN OF TWO-PHASE SINUSOIDAL POWER CLOCK AND CLOCKED TRANSMISSION GATE ADIABATIC LOGIC CIRCUIT

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Journal of Electronics(China) 2007年第2期24卷 225-231页

作者： wang Pengjun yu Junjun Institute of Circuits and Systems Ningbo University Ningbo 315211 China

First the research is conducted on the design of the two-phase sinusoidal power clock generator in this paper. Then the design of the new adiabatic logic circuit adopting the two-phase sinusoidal power clocks--Clocked Transmission Gate Adiabatic Logic （CTGAL） circuit is presented. This circuit makes use of the clocked transmission gates to sample the input signals, then the output loads are charged and discharged in a fully adiabatic manner by using bootstrapped N-Channel Metal Oxide Semiconductor （NMOS） and Complementary Metal Oxide Semiconductor （CMOS） latch structure. Finally, with the parameters of Taiwan Semiconductor Manufacturing Company （TSMC） 0.25um CMOS device, the transient energy consumption of CTGAL, Bootstrap Charge-Recovery Logic （BCRL） and Pass-transistor Adiabatic Logic （PAL） including their clock generators is simulated. The simulation result indicates that CTGAL circuit has the characteristic of remarkably low energy consumption.

关键词： Circuit design Two-phase sinusoidal power clock Clock generator Clocked Transmission Gate Adiabatic Logic (CTGAL) circuit

Simulation of a soft-gamma-ray polarimeter on board a microsatellite

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Nuclear Science and Techniques 2023年第11期34卷 64-76页

作者： Xiang‑Man Liu Shu‑Wen Tang Wei wang yu‑Hong yu Zhi‑yu Sun Yong‑Jie Zhang Fang Fang Duo Yan Shi‑Tao wang Xue‑Heng Zhang Shu‑Ya Jin Bi‑Tao Hu Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Department of Astronomy School of Physics and TechnologyWuhan UniversityWuhan 430072China Wuhan University‑National Astronomical Observatories Joint Center for Astronomy Wuhan UniversityWuhan 430072China

Gamma-ray polarimetry is a new and prospective tool for studying extremely high-energy celestial objects and is of great significance for the field of *** the rapid development of microsatellite technology,the advantages of space exploration have become increasingly ***,we simulated a soft-gamma-ray polarimeter for a microsatellite based on the Compton scattering *** performed detailed Monte Carlo simulations using monoenergetic gamma-ray linear-polarization sources and Crab-like sources in the energy range of 0.1-10 MeV considering the orbital *** polarimeter exhibited excellent polarization detection *** modulation factor was 0.80±0.01,and the polarization angles were accurate within an error of 0.2°at 200 keV for on-axis *** the Crab-like sources for on-axis incidence,the polarization degrees were consistent with the set values within the error tolerance,the modulation factor was 0.76±0.01,and the minimum detectable polarization reached 2.4%at 3σfor an observation time of10^(6) ***,the polarimeter exhibited recoil electron tracking,imaging,and powerful background suppression in a large field of view(FoV;∼2πsr).The proposed polarimeter meets the requirements of a space soft-gamma-ray polarization detector and has promising research prospects.

关键词： Soft gamma ray Polarization Compton scattering Microsatellite Monte Carlo simulation

Arch formation mechanism and discharge process of cohesive fine powder in a vibrated silo

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Particuology 2024年第11期94卷 373-385页

作者： Jingzhen Zhu Kun wang yu Ma Wentao Xu Jiecai Long Xiwen Li State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou510006China

The arch formation mechanism and discharge process of a very cohesive fine powder(calcium carbonate)in a vibrated silo was investigated by experiments and discrete element method(DEM)*** experimental setup is built to study the flow behaviors with the proposed image-based flow rate measurement method.A cohesive DEM model is used to investigate the dynamic behaviors of the powder *** indicate that the arch formation depends on the vibration acceleration amplitude and is slightly affected by the *** powder discharge flow rate increases with vibration acceleration amplitude and decreases with *** the acceleration amplitude exceeds 15 g,the flow rate tends to *** the acceleration amplitude exceeds 1 g,there is separation and collision between the powder bed and the silo *** collision leads to a significant increase in the contact force.

关键词： Cohesive fine powder Silo discharge Vertical vibration Arch formation Flow rate Discrete element method

Spotlight: Hot Target Discovery and Localization with Crowdsourced Photos

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Tsinghua Science and Technology 2020年第1期25卷 68-80页

作者： Jiaxi Gu Jiliang wang Lan Zhang Zhiwen yu Xiaozhe Xin yunhao Liu School of Computer Science Northwestern Polytechnical UniversityXi’an 710072China School of Software Tsinghua UniversityBeijing 100084China School of Computer Science and Technology University of Science and Technology of ChinaHefei 230026China Beijing Sogou Technology Development Co. Ltd.Beijing 100084China

Camera-equipped mobile devices are encouraging people to take more photos and the development and growth of social networks is making it increasingly popular to share photos online. When objects appear in overlapping Fields Of View(FOV), this means that they are drawing much attention and thus indicates their popularity. Successfully discovering and locating these objects can be very useful for many applications, such as criminal investigations, event summaries, and crowdsourcing-based Geographical Information Systems(GIS).Existing methods require either prior knowledge of the environment or intentional photographing. In this paper, we propose a seamless approach called 'Spotlight', which performs passive localization using crowdsourced *** a graph-based model, we combine object images across multiple camera views. Within each set of combined object images, a photographing map is built on which object localization is performed using plane geometry. We evaluate the system’s localization accuracy using photos taken in various scenarios, with the results showing our approach to be effective for passive object localization and to achieve a high level of accuracy.

关键词： crowdsourcing localization multimedia mobile computing

Evaluation of the technoeconomic feasibility of electrochemical hydrogen peroxide production for decentralized water treatment

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Frontiers of Environmental Science & Engineering 2021年第1期15卷 31-45页

作者： Yang Li Yixin Zhang Guangshen Xia Juhong Zhan Gang yu yujue wang School of Environment State Key Joint Laboratory of Environmental Simulation and Pollution ControlBeijing Key Laboratory for Emerging Organic Contaminants ControlTsinghua UniversityBeijing 100084China

This study evaluated the feasibility of electrochemical hydrogen peroxide(H2O2)production with gas diffusion electrode(GDE)for decentralized water *** black-polytetrafluoroethylene GDEs were prepared and tested in a continuous flow electrochemical cell for H2O2 production from oxygen *** showed that because of the effective oxygen transfer in GDEs,the electrode maintained high apparent current efficiencies(ACEs,>80%)for H_(2)O_(2) production over a wide current density range of 5–400 mA/cm^(2),and H_(2)O_(2) production rates as high as~202 mg/h/cm^(2) could be ***-term stability test showed that the GDE maintained high ACEs(>85%)and low energy consumption(<10 kWh/kg H2O2)for H_(2)O_(2) production for 42 d(~1000 h).However,the ACEs then decreased to~70%in the following 4 days because water flooding of GDE pores considerably impeded oxygen transport at the late stage of the *** on an electrode lifetime of 46 days,the overall cost for H2O2 production was estimated to be~0.88$/kg H_(2)O_(2),including an electricity cost of 0.61$/kg and an electrode capital cost of 0.27$/*** a 9 cm^(2) GDE and 40 mA/cm^(2) current density,~2–4 mg/L of H2O2 could be produced on site for the electro-peroxone treatment of a 1.2 m^(3)/d groundwater flow,which considerably enhanced ibuprofen abatement compared with ozonation alone(~43%–59%vs.7%).These findings suggest that electrochemical H_(2)O_(2) production with GDEs holds great promise for the development of compact treatment technologies for decentralized water treatment at a household and community level.

关键词： Advanced oxidation process Electro-peroxone Gas diffusion electrode Hydrogen peroxide Oxygen reduction

Influence of process parameters and aging treatment on the microstructure and mechanical properties of Al Si8Mg3 alloy fabricated by selective laser melting

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1770-1779页

作者： Yaoxiang Geng Hao Tang Junhua Xu yu Hou yuxin wang Zhen He Zhijie Zhang Hongbo Ju Lihua yu School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Many studies have investigated the selective laser melting(SLM)of AlSi10Mg and AlSi7Mg alloys,but there are still lack of researches focused on Al-Si-Mg alloys specifically tailored for *** this work,a novel high Mg-content AlSi8Mg3 alloy was specifically designed for *** results showed that this new alloy exhibited excellent SLM processability with a lowest porosity of 0.07%.Massive lattice distortion led to a high Vickers hardness in samples fabricated at a high laser power due to the precipitation of Mg_(2)Si nanoparticles from theα-Al matrix induced by high-intensity intrinsic heat treatment during *** maximum microhardness and compressive yield strength of the alloy reached HV(211±4)and(526±12)MPa,*** aging treatment at 150℃,the maximum microhardness and compressive yield strength of the samples were further improved to HV(221±4)and(577±5)MPa,*** values are higher than those of most known aluminum alloys fabricated by *** paper provides a new idea for optimizing the mechanical properties of Al-Si-Mg alloys fabricated using SLM.

关键词： AlSi8Mg3 alloy selective laser melting process parameters microstructure aging treatment mechanical properties

A performance-based hybrid deep learning model for predicting TBM advance rate using Attention-ResNet-LSTM

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 65-80页

作者： Sihao yu Zixin Zhang Shuaifeng wang Xin Huang Qinghua Lei Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghaiChina Key Laboratory of Geotechnical and Underground Engineering Ministry of EducationTongji UniversityShanghaiChina Department of Earth Sciences ETH ZürichZürichSwitzerland Department of Earth Sciences Uppsala UniversityUppsalaSweden

The technology of tunnel boring machine(TBM)has been widely applied for underground construction worldwide;however,how to ensure the TBM tunneling process safe and efficient remains a major *** rate is a key parameter of TBM operation and reflects the TBM-ground interaction,for which a reliable prediction helps optimize the TBM ***,we develop a hybrid neural network model,called Attention-ResNet-LSTM,for accurate prediction of the TBM advance rate.A database including geological properties and TBM operational parameters from the Yangtze River Natural Gas Pipeline Project is used to train and test this deep learning *** evolutionary polynomial regression method is adopted to aid the selection of input *** results of numerical exper-iments show that our Attention-ResNet-LSTM model outperforms other commonly-used intelligent models with a lower root mean square error and a lower mean absolute percentage ***,parametric analyses are conducted to explore the effects of the sequence length of historical data and the model architecture on the prediction accuracy.A correlation analysis between the input and output parameters is also implemented to provide guidance for adjusting relevant TBM operational *** performance of our hybrid intelligent model is demonstrated in a case study of TBM tunneling through a complex ground with variable ***,data collected from the Baimang River Tunnel Project in Shenzhen of China are used to further test the generalization of our *** results indicate that,compared to the conventional ResNet-LSTM model,our model has a better predictive capability for scenarios with unknown datasets due to its self-adaptive characteristic.

关键词： Tunnel boring machine(TBM) Advance rate Deep learning Attention-ResNet-LSTM Evolutionary polynomial regression

Investigation on insulation properties of HFO-1336mzz(E)and N_(2)/CO_(2)mixtures as SF_(6) substitutes in gas-insulated electrical applications

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High Voltage 2023年第1期8卷 48-58页

作者： Zhanyang Gao yunbai Luo Ruichao Peng Xiaoxiao wang Ping yu Wenjun Zhou Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhanChina School of Electrical Engineering and Automation Wuhan UniversityWuhanChina

The emissions of SF6 have been restricted owing to 3400 years of atmospheric lifetime and high global warming potential(GWP)as an insulating gas in gas-insulated electrical *** this study,HFO-1336mzz(E)and N_(2)/CO_(2)mixtures are proposed as SF6 substitutes for their short atmospheric lifetime,low GWP and superior insulation *** GWP of HFO-1336mzz(E)is only 18 and its atmospheric lifetime is days to *** breakdown voltage of 25%HFO-1336mzz(E)and N_(2)/CO_(2)mixtures is about 85%that of pure SF6 under alternating *** self-recovery ability of HFO-1336mzz(E)and CO_(2)mixtures is superior to that of HFO-1336mzz(E)and N_(2)*** decomposition characteristic of HFO-1336mzz(E)shows that a tiny amount of its gas might initiate a carbonisation reaction to form carbon after multiple breakdown tests,which is verified by observations using energy dispersive X-rays spectroscopy and scanning electron *** acute toxicity test of HFO-1336mzz(E)indicates that the gas is *** results show that HFO-1336mzz(E)and N_(2)/CO_(2)mixtures are potential substitutes for SF6 in electrical applications.

关键词： SF6 electrical insulation

Electromagnetic transitions in multiple chiral doublet bands

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Chinese Physics C 2016年第12期40卷 91-98页

作者： Hui Jia Bin Qi Shou-yu wang Shuo wang Chen Liu Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Weihai 264209 China

Multiple chiral doublet bands （MχD） in the 80, 130 and 190 mass regions are studied by the model of γ=90°triaxial rotor coupled with identical symmetric proton-neutron configurations. By selecting a suitable basis, the calculated wave functions are explicitly exhibited to be symmetric under the operator A, which is defined as rotation by 90° about the 3-axis with the exchange of valance proton and neutron. We found that both M1 and E2 transitions are allowed between levels with different values of A, while they are forbidden between levels with same values of A. Such a selection rule holds true for MχD in different mass regions.

关键词： chiral doublet bands electromagnetic transition selection rule particle rotor model