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Numerical study on indoor environment and thermal comfort in train station waiting hall with two different air-conditioning modes

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Building Simulation 2021年第2期14卷 337-349页

作者： Biyao Zhuang juan Shi Zhenqian Chen Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education of China School of Energy and EnvironmentSoutheast UniversityNanjing210096China

With the increasing size of the waiting hall,the large-area use of transparent envelope materials makes the interior surface temperature of the envelope too high,which puts forward higher requirements for the control of environment and thermal comfort *** this paper,the characteristics of indoor temperature distribution,relative humidity distribution and thermal comfort under the all air system(AAs)and the radiant floor cooling and wall cooling combined with air supply system(RC/ASs)were investigated in the large *** computational fluid dynamics(CFD)method was used,and the performance of the CFD model was validated by comparing the measured results with CFD simulation results in the *** numerical results clearly showed that the temperature and relative humidity indoors could satisfy the design requirement both in the AAs and RC/*** indoor air distribution in most areas under the RC/ASs was more uniform based on the indoor heat and humidity requirements under the cooling load of measured *** the AAs,the total cooling capacity of air conditioning unit was the highest when indoor thermal comfort was the best,that meant that to achieve the best working condition,the air-conditioning system need high energy ***,the RC/ASs addressed the problem that the temperature around the seated passengers in the waiting area was relatively high in the *** paper will provide reference for the air conditioning system design in the similar large spaces in the future.

关键词： radiant floor cooling radiant wall cooling large spaces thermal comfort

Calculating the Wave Force on Partially Immersed Large-Scale Horizontal Cylinders

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China Ocean Engineering 2021年第2期35卷 291-300页

作者： LIU Bi-jin FU Dan-juan School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen 361024China

Large-scale interceptors constitute the main structure of offshore self-driven floating marine litter collection devices,and the structural stability of such interceptors under the action of waves directly influences the overall safety of the *** the ratio of the diameter of a horizontal cylinder in such interceptors to the incident wavelength is larger than 0.25,the wave force can be calculated by using the diffraction theory,by considering the problem as that of the interaction between the waves and a partially immersed large-scale horizontal *** this study,an analytical approach to calculate the wave force on a partially immersed large-scale horizontal cylinder was formulated by using the stepwise approximation *** model tests were conducted to investigate the effects of different factors(wave height,period,and immersion depth)on the wave force on a large-scale horizontal cylinder under conditions involving short-period *** results show that both horizontal and vertical wave forces on the cylinder increase as the wave height(immersion depth)increases in most *** vertical wave force decreases with the decrease of the *** the horizontal wave force,it increases with the decrease of the period when the wavelength is larger than the diameter of the cylinder and decreases with the decrease of the period when the wavelength is smaller than the diameter of the cylinder.

关键词： wave force large-scale horizontal cylinder diffraction theory partial immersion stepwise approximation method

A cloud-based platform to predict wind pressure coefficients on buildings

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Building Simulation 2022年第8期15卷 1507-1525页

作者： Facundo Bre juan M.Gimenez Centro de Investigacion de Metodos Computacionales(CIMEC) UNLCONICETPredio"Dr.Alberto Cassano"Colectora Ruta Nacional 168 s/n3000Santa FeArgentina

Natural ventilation(NV)is a key passive strategy to design energy-efficient buildings and improve indoor air ***,accurate modeling of the NV effects is a basic requirement to include this technique during the building design ***,there is an important lack of wind pressure coefficients(CP)data,essential input parameters for NV *** this,there are no simple but still reliable tools to predict CP data on buildings with arbitrary shapes and surrounding conditions,which means a significant limitation to NV modeling in real *** this reason,the present contribution proposes a novel cloud-based platform to predict wind pressure coefficients on *** platform comprises a set of tools for performing fully unattended computational fluid dynamics(CFD)simulations of the atmospheric boundary layer and getting reliable CP data for actual ***-expert decisions throughout the entire workflow are implemented to automatize the generation of the computational domain,the meshing procedure the solution stage,and the post-processing of the *** evaluate the performance of the platform,an exhaustive validation against wind tunnel experimental data is carried out for a wide range of case *** include buildings with openings,balconies,irregular floor-plans,and surrounding urban *** C_(P) results are in close agreement with experimental data,reducing 60%-77% the prediction error on the openings regarding the EnergyPlus *** platform introduced shows being a reliable and practical C_(P) data source for NV modeling in real building design scenarios.

关键词： natural ventilation building simulation airflow network model EnergyPlus wind pressure coefficient computational fluid dynamics

Research on the measurement of the price change of telecom services in China

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 110-113页

作者： ZHAO Hui-juan Management Department Xi'an University of Posts and TelecommunicationsXi'an 710061 China

It is difficult to measure the total change of the telecom service price （TSP） in China due to the complexity of TSP and the diversity of telecom service. This article analyzes the relation between telecom service revenue and traffic volumes of telecom service and deduces the method of measuring the total change in tendency of telecom price, which is based on the consumer＇s actual payment for telecom services. After describing the changing trend of TSP with the time series data from 1949 to 2000, the TSP showed a continuous declining tendency during 1949～1975. In contrast, the TSP showed a rising tendency from 1976 to 1991 and a sharp declining trend after 1992. Empirical tests and actual background of telecom reform support the results.

关键词： price telecom service price revenue traffic volumes of telecom service

Atmospheric deposition of 7Be,210Pb and 210Po during typhoons and thunderstorm in Shanghai, China and global data synthesis

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Science China Earth Sciences 2020年第4期63卷 602-614页

作者： juan DU Mark BASKARAN Jinzhou DU State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China Department of Geology Wayne State UniversityDetroit 48202USA

Atmospherically-delivered ~7Be,^(210)Po and ^(210)Pb in bulk precipitation and air samples collected around the globe have provided valuable quantification on the rates of removal, as well as proportional mixing of attendant air masses;however, such studies during thunderstorm and typhoon events are limited. We report the first continuous time-series rainwater sampling and analysis of ~7Be,^(210)Pb and ^(210)Po from two typhoons and one thunderstorm during 2015 summer in Shanghai. The depositional fluxes within individual rain events of typhoons and thunderstorms varied by a factor of 10 for ~7Be, 5.7 for ^(210)Pb, 7.4 for ^(210)Po,and 7.0 for ~7Be/^(210)Pb activity ratios(AR). Such large observed variations in the depositional fluxes of ~7Be,^(210)Pb,^(210)Po and ~7Be/^(210)Pb activity ratios were attributed to air masses injected from surrounding high pressure system adjoining the typhoon to low pressure system within the typhoon. Based on ~7Be/^(210)Pb activity ratios, we estimated the variations in the fraction of maritime and continental air masses into the typhoon. Observed constancy in the ^(210)Po/^(210)Pb AR indicates that the residence times of air masses contributing to the typhoon during heavy rain are similar. From a synthesis of global fallout of ~7Be and ^(210)Pb during pulse events(precipitation≥50 mm from single rainout event), we quantify the importance of pulse events in the atmospheric fallout of these radionuclides.

关键词： 7Be 210Pb 210Po Typhoon Thunderstorm Air masses intrusions

Impact of FY-3A MWTS radiances on prediction in GRAPES with comparison of two quality control schemes

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Frontiers of Earth Science 2014年第2期8卷 251-263页

作者： juan LI Xiaolei ZOU National Meteorological Center China Meteorological Administration Beijing 100081 China Department of Earth Ocean and Atmospheric Sciences Florida State University Tallahassee 32306 USA

The impact of Microwave Temperature Sounder （MWTS） radiances on the prediction of the Chinese Numerical Weather prediction （NWP） system-GRAPES （Global and Regional Assimilation and PrEdiction System） with comparison of two Quality Control （QC） schemes was researched. The main differences between the two schemes are cloud detection, O-B （brightness temperature difference between observation and model simulation） check and thinning. To evaluate the impact of the two QC schemes on GRAPES, a typhoon case study and cycle experiments were conducted. In the typhoon case study, two experiments were conducted using both the new and old QC schemes. The results show that outliers are removed in the new QC while they exist in the old QC. The analysis and the model forecast are subsequently generated after assimilating data from the two QC schemes. The model-predicted steering flows more southward with the new QC scheme, and as a result, the forecast track in the experiments is more southward, i.e., closer to the best track than the old scheme. In addition to the case study, four impact cycle experiments were conducted for 25-day periods. The results show that the new QC scheme removed nearly all the biases whereas the old scheme could not. Furthermore, the mean and standard deviation of analysis increments with the new scheme is much smaller than those of O-B. In contrast, the old scheme values are either slightly smaller or the same. Verifications indicate that forecast skill is improved after applying the new scheme. The largest improvements are found in the Southern Hemisphere. According to the results above, MWTS with the new QC scheme can improve the GRAPES forecast.

关键词： FY-3 MWTS typhoon GRAPES

Dynamically Running Mass of Light Quark and QCD Vacuum Condensates

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Communications in Theoretical Physics 2004年第6X期42卷 875-883页

作者： ZHOULi-juan PINGRong-Gang DepartmentofInformationandComputingSciences GuangxiUniversityofTechnologyLiuzhou545006China//DepartmentofPhysicsGuangxiUniversityNanning530004China InstituteofHighEnergyPhysics AcademiaSinicaBeijing100039China

Based on Dyson-Schwinger equations (DSEs) in "rainbow" approximation, the dynamically running mass of light quark and QCD vacuum condensate are investigated. The structure of non-local quark vacuum condensate, the values of local vacuum condensate of quarks and quark-gluon mixture, and dynamical transition of quark mass from current quark to constituent quark are illustrated. At the same time, according to the knowledge and experience learned from an extensive study of the solutions of DSEs, a parameterized form of confining quark propagator is suggested for a practical use. The new parameterized form of quark propagator is analytic everywhere in the finite complex p2-plane and has no Lehmann representation. The predictions for p2-dependence of effective quark masses, Mf(p2), defined by the self-energy functions Af(p2) and Bf(p2), both from the numerical solutions of DSEs and from its parameterized form, are shown dynamically. Our conclusion is that all numerical results are consistent with empirical values used in QCD sum rules and lattice QCD calculations. For a qualitative study, the parameterized form is a sufficiently good approximation to confining quark propagator.

关键词：夸克质量夸克传播者代森-施温格方程非摄动QCD

The Impact of Boreal Autumn SST Anomalies over the South Pacific on Boreal Winter Precipitation over East Asia

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Advances in Atmospheric Sciences 2016年第5期33卷 644-655页

作者： juan AO Jianqi SUN Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 University of Chinese Academy of Sciences Beijing 100049

The possible mechanism behind the variability in the dipole pattern of boreal winter precipitation over East Asia is analyzed in this study. The results show that the SST anomalies（SSTAs） over the South Pacific Ocean（SPO） in boreal autumn are closely related to the variability in the dipole pattern of boreal winter precipitation over East Asia. The physical link between the boreal autumn SPO SSTAs and the boreal winter East Asian precipitation dipole pattern is shown to mainly be the seasonal persistence of the SPO SSTAs themselves. The seasonal persistence of the SPO SSTAs can memorize and transport the signal of the boreal autumn SSTAs to the following winter, and then stimulates a meridional teleconnection pattern from the SH to the NH, resulting in a meridional dipole pattern of atmospheric circulation over East Asia in boreal winter. As a major influencing factor, this dipole pattern of the atmospheric circulation can finally lead to the anomalous precipitation dipole pattern over East Asia in boreal winter. These observed physical processes are further confirmed in this study through numerical simulation. The evidence from this study, showing the impact of the SPO SSTAs in boreal autumn,not only deepens our understanding of the variability in East Asian boreal winter precipitation, but also provides a potentially useful predictor for precipitation in the region.

关键词： SST boreal winter precipitation dipolar pattern atmospheric circulation zonal wind

Synergistic effect of Ni^(Ⅱ)and Co/Fe^(Ⅲ)in doped mixed-valence phosphonate for enhancing electrocatalytic oxygen evolution

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Green Energy & Environment 2022年第3期7卷 432-439页

作者： juan-juan Hou Jian-Tao Yuan Wei Zhang Ying-Xia Wang Xian-Ming Zhang Key Laboratory of Magnetic Molecules and Magnetic Information Materials(Ministry of Education) School of Chemistry and Material ScienceShanxi Normal UniversityLinfen041004China

Metal organophosphonates have been explored in energy-related fields due to their high chemical and thermal stability as a type of uniformly precursor,but only few of pristine metal organophosphonate are directly used for oxygen evolution reaction(OER)***,a mixedvalence iron phosphonate(Fe_(3)-ppat)has been constructed and applied to OER catalysis considered the potential active sites in pillars Fe^(Ⅱ)(-H_(2)O)_(4)(COO)_(2)and inorganic layers Fe^(Ⅲ)(μ_(2)–OH)PO_(3).Specifically,isostructural trimetallic framework Fe_(1.7)Co_(0.3)Ni_(1.0)-ppat possesses a minimum overpotential(291 mV),small Tafel slope(91.65 mV dec^(-1)),and high stability up to 83 *** enhanced catalytic performance could be mainly ascribed to the synergistic effect of Ni^(Ⅱ)equivalent occupancy in pillars and Co/Fe^(Ⅲ)in layers.

关键词： phosphonate stability organo