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Operation Performance of Central Solar Heating System with Seasonal Storage Water Tank in Harbin

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湖南大学学报（自然科学版） 2009年第S1期36卷 111-114页

作者： YE Ling1,JIANG Yi-qiang1,YAO Yang1,ZHANG Shi-cong2(1.Institute of Heat Pump and Air Conditioning Technology,Harbin Institute of Technology,Harbin,Heilongjiang 150090,china 2.Institute of Built environment and energy efficiency,china academy of building research,beijing 100013.china) Institute of Heat Pump and Air Conditioning Technology Harbin Institute of Technology Harbin 150090 China Institute of Built environment and energy efficiency China Academy of Building Research Beijing 100013 China

This paper presented a preliminary research on the central solar heating system with seasonal storage(CSHSSS)used in cold climate in china.A mathematical model of the solar energy seasonal storage water tank used in the central solar heating system was firstly developed based on energy *** was followed by the simulation of the CSHSSS used in a two-floor villa in Harbin,and analysis of the impacts on storage water temperature of tank volume,solar collector area,tank burial depth,insulation thickness around the tank,*** results show there is a relatively economical tank volume to optimize the system efficiency,which decreases with increasing tank volume at the constant collector area,and increases with increasing collector area at the constant tank ***,the insulation thickness has obvious effect on avoiding heat loss,while the tank burial depth doesn'*** addition,the relationship between the solar collector efficiency and storage water temperature is also obtained,it decreases quickly with increasing storing water temperature,and then increases slowly after starting space heating *** may be helpful for relevant design and optimization in cold climates in china and all over the world.

关键词： central solar heating system with seasonal storage(CSHSSS) simulation system efficiency storage water tank villa

GHG emission reductions and costs to achieve Kyoto target

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Journal of environmental Sciences 2003年第4期15卷 541-547页

作者： CHEN Wen\|ying (energy, environment and Economy research Institute, Tsinghua University, beijing 100084, china.) energy Environment and Economy Research Institute Tsinghua University 北京 100084

Emission projection and marginal abatement cost curves(MACs) are the central components of any assessment of future carbon market, such as CDM (clean development mechanism) potentials, carbon quota price etc. However, they are products of very complex, dynamic systems driven by forces like population growth, economic development, resource endowments, technology progress and so on. The modeling approaches for emission projection and MACs evaluation were summarized, and some major models and their results were compared. Accordingly, reduction and cost requirements to achieve the Kyoto target were estimated. It is concluded that Annex I Parties' total reduction requirements range from 503—1304 MtC with USA participation and decrease significantly to 140—612 MtC after USA's withdrawal. Total costs vary from 21—77 BUSD with USA and from 5—36 BUSD without USA if only domestic reduction actions are taken. The costs would sharply reduce while considering the three flexible mechanisms defined in the Kyoto Protocol with domestic actions' share in the all mitigation strategies drops to only 0—16%.

关键词： Kyoto Protocol emission reduction abatement cost flexible mechanisms

Unsteady Numerical Simulation of Hot Streak/Blades Interaction and Film Cooling

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Journal of Thermal Science 2010年第5期19卷 402-409页

作者： Weilin Yi,Lucheng Ji and Yunhan Xiao research Center for energy and Power,Chinese academy of Sciences,beijing,china Key Laboratory of Advanced energy and Power,Chinese academy of Sciences,(Institute of Engineering Thermophysics),beijing,china P.O.Box 2706,beijing 100190,china research Center for energy and Power Chinese Academy of Sciences Beijing China Key Laboratory of Advanced energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China beijing China

Deeply research on management and application of hot streak is an important way to breakthrough technique obstacle of aero engine hot *** method is a useful instrument to investigate the correlative *** the paper developed independently three dimensional unsteady parallel computational code-MpiTurbo based on Fortran 90 and MPI at Linux operating *** unsteady numerical simulation was carried out to investigate impacts of the factors,which included circumferential locations of hot streak and clocking positions of blade rows,on the thermal environment of a 1+1 counter-rotating *** results clearly indicated that clocking positions of hot streak/blade row and blade row/blade row had great influence on the time-averaged temperature distribution of the third blade ***,it can be effective for improving thermal environment of turbine to optimize blade parameters and clocking *** film cooling layout was designed by the repetitious steady simulation based on source term *** the flow structure detail was given by the unsteady simulation.

关键词： hot streak turbine parallel computation film cooling

energy Consumption by Rural Households in Northern Hunan

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湖南大学学报（自然科学版） 2009年第S1期36卷 182-185页

作者： LI Lin,ZHOU Jin,ZHANG Guo-qiang(research Center for building environment and energy Saving,Hunan University,Changsha,Hunan 410082,china) research Center for building environment and energy Saving Hunan University Changsha 410082 China

This study was conducted to investigate the household energy consumption in rural districts in northern Hunan and to help explore the sustainable and ecological energy *** were used to acquire the details of energy consumption,and the electricity equivalent calculation was used in the energy statistics in four *** energy consumption in these four villages is influenced by the economic condition,geographic position and landform and the local *** traditional biomass energy and coal briquette are the primary energy source for cooking and heating,but they are used in a very low efficiency and result in poor *** sustainability,further measures should be taken to optimize the energy consumption with the efficient use of biomass energy,coal and electricity.

关键词： structure amount rural energy consumption northern Hunan

A COUPLED MODEL OF HYDRODYNAMICS AND WATER QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun School of environment Beijing Normal University Beijing 100875 China Department of Water environment China Institute of Water Resources and Hydropower Research Beijing100038 China Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 44.0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

A formal semantics for program debugging

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Science china(Information Sciences) 2012年第1期55卷 133-148页

作者： LI Wei1&LI Ning1,2 1State Key Laboratory of Software Development environment,School of Computer Science and Engineering,Beihang University,beijing 100191,china 2china Ship research and Development academy,beijing 100192,china 1. State Key Laboratory of Software Development environment School of Computer Science and Engineering Beihang University Beijing 100191 China2. China Ship Research and Development Academy Beijing 100192 China

This work aims to build a semantic framework for automated debugging.A debugging process consists of tracing,locating,and fixing processes *** first two processes are accomplished by a tracing procedure and a locating procedure,*** tracing procedure reproduces the execution of the failed test case with well-designed data structures and saves necessary information for locating *** locating procedure will use the information obtained from the tracing procedure to locate ill-designed statements and to generate a system of fix-equations,whose solution will be used to fix the bugs.A structural operational semantics is given to define the functions of the tracing and locating *** of them are proved to *** main task of fixing process is to solve the *** turns out that for a given failed test case,there exist four types of fix-equations and three dierent solutions:1)The bug is solvable,i.e.,there exists a solution of the system of fix-equations,and the program can be repaired.2)There exists a structural design error in the program,i.e.,the system of fix-equations generated at each round of the locating procedure is solvable,but a new bug will arise when the old bug is being fixed.3)There exists a logical design error,and the system of fix-equations is not solvable.

关键词： debugging operational semantics failed test case fix-equations

A preliminary analysis of physical mechanism of transformation process from a landed typhoon into an extratropical cyclone

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Acta Oceanologica Sinica 1992年第4期11卷 525-535页

作者： Zhang Qiuqing and Ding Yihui 1. National research Center for Marine. environment Forecasts, beijing 100081, china2. academy of Meteorological Science, State Meteorological Administration, beijing 100081, china National research Center for Marine environment Forecasts Beijing 100081 China China

A diagnostic study is performed in the paper on the process of typhoon Norris (1980) transforming into an ex-tratropical cyclone after its landing over Southeast china. The main findings are as follows:The changes of kinetic energy are mainly attributed to the generation due to non-divergent wind. During the early stage of the typhoon landing, there exits only a small quantity of kinetic energy exchanging with the environment. And after it is transformed into an extratropical cyclone, a large amount of kinetic energy is exported from the system toward the *** horizontal and vertical flux-divergence terms of eddy available potenlial energy are the prominent sinks in the budgets of eddy kinetic energy. The generations of eddy kinetic energy due to both the barotropic and baroclinic processes are source terms. The former is remarkable during the initial stage. But after the depression is transformed into an extratropical cyclone, the roles of the generation by the barotropic and baroclinic processes are reversed, 1. e. , the latter has become more significant than the *** heating is the most dominant heat source. The terms of vertical heat flux by cumulus and large-scale motion are the major sinks. And the latter is prominent after the system is transformed into an extratropical cycfone.

关键词： A preliminary analysis of physical mechanism of transformation process from a landed typhoon into an extratropical cyclone

Numerical study on optical and electric-thermal performance for solar concentrating PV/T air system

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Science china(Technological Sciences) 2009年第12期52卷 3514-3520页

作者： SUN Jian 1,2 &SHI MingHeng 1 1School of energy and environment,Southeast University,Nanjing 210096,china 2Department of Thermal energy Engineering,Jingdezhen Ceramic Institute,Jingdezhen 333001,china 1. School of energy and environment Southeast University Nanjing 210096 China 2. Department of Thermal energy Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China

Hybrid photovoltaic/thermal(PV/T)system with solar concentrator is an effective way to improve solar energy conversion *** this work,a single-pass PV/T air system with a three-trough compound parabolic concentrator(CPC)of concentration ratio 2.0 is designed and the solar incident distributions at the solar cell surface are calculated by ray tracing *** on energy balance,the heat transfer models of all main components in this system are *** effects of some main designing and operational parameters on the electric-thermal performance of the system are analyzed. The results show that the solar radiation intensity can be higher than 1200 W/m 2 at most area of the cell *** temperature of the air and cell surface increases along the length of the *** the system efficiency of the CPC is higher than that of the system without the *** thermal efficiency, exergy and electrical efficiency of this CPC system increase with increasing of the air mass flow rate and the length of the *** increasing packing fraction the electrical efficiency increases,but the thermal efficiency *** exergy efficiency increases slightly with the packing fraction *** data obtained in this work are valuable for the design and operation for this kind of solar concentrating PV/T systems.

关键词： photovoltaic/thermal system CPC exergy efficiency thermal and electricity performance optical

Effects of diatoms on reproduction and growth of marine copepods

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Progress in Natural Science:Materials International 2004年第10期14卷 1-7页

作者： ZHANG Guangtao 1,2 and SUN Song 1 (1.Key Laboratory of Marine Ecology&environment Sciences,Institute of Oceanology,Chinese academy of Sciences,Qingdao266071,china 2.Graduate School,Chinese academy of Sciences,beijing100039,china) Chinese Acad Sci Inst Oceanol Key Lab Marine Ecol & Environm Sci Qingdao 266071 Peoples R China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

Two hot spots in marine ecology,deleterious effects of diatoms and feeding selectivity of copepods,as well as new progress on these two issues achieved in the recent ten years,are *** two issues are considered correlated *** and their metabolites can induce deleterious effects on growth,reproduction and development of copepods,including increase of mortality and decrease of egg production,hatching and growth *** negative effects,resulting from either chemical toxin or nutritional defi-ciency,can be conquered in natural environments by diverse *** is therefore concluded that deleterious effects of diatoms observed in laboratory or during blooming period are only a special case that accommodation of feeding strategy of copepods is *** under-stand their feeding strategy in natural environments is a prerequisite to explaining the mechanisms of deleterious effects caused by diatoms,and makes it possible to re-evaluate the energy flow in marine ecosystems.

关键词： diatoms copepod feeding strategy reproduction deleterious effects