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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

Black-box testing based on colorful taint analysis

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Science china(Information sciences) 2012年第1期55卷 171-183页

作者： CHEN Kai1,2,3,FENG DengGuo1,SU PuRui1&ZHANG YingJun1,2,3 1State Key Laboratory of Information Security,institute of Software,chinese academy of Science,beijing 100190,china 2State Key Laboratory of Information Security,Graduate University of chinese academy of sciences,beijing 100049,china 3national engineering research center of Information Security,beijing 100190,china State Key Laboratory of Information Security Institute of Software Chinese Academy of Science Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China national engineering research center of Information Security Beijing China

Software vulnerability detection is one of the most important methods for guaranteeing software *** main classes of methods can detect vulnerabilities in binary files:white-box testing and black-box *** former needs to construct and solve path constraints to detect *** has two main drawbacks:path exploding and complexity of *** latter often aimlessly exhausts various inputs to test binary *** paper combines both testing methods to detect vulnerabilities in binary *** analyzing the input elements that aect check condition corresponding to a certain check point,we can generate one class of inputs that get to the check point to increase fuzzing *** analyzing the relationship between guard conditions and check condition,the redundant check points are *** taint analysis method(CTAM)is proposed to compute guard conditions,which is more ecient than traditional taint analysis method(TTAM).We implemented a prototype and made several experiments on *** results showed that our method could increase the eciency of black-box testing.

关键词： software testing vulnerability detection dynamic testing black-box testing colorful taint analysis

Heavy ion reactions around the Coulomb barrier

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 6-13页

作者： ZHANG HuanQiao1, LIN ChengJian1, JIA HuiMing1, ZHANG ChunLei1,2, ZHANG GaoLong1,3, YANG Feng1, LIU ZuHua1, AN GuangPeng1, WU ZhenDong1, XU XinXing1 & JIA Fei1 1 china institute of Atomic Energy, P. O. box 275(10), beijing 102413, china 2 Particle Astrophysics center, institute of High Energy Physics, chinese academy of sciences, beijing 100039, china 3 School of Physics and Nuclear Energy engineering, Beihang University, beijing 100191, china china institute of Atomic Energy Beijing China Particle Astrophysics center Institute of High Energy Physics Chinese Academy of Sciences Beijing China School of Physics and Nuclear Energy engineering Beihang University Beijing China

The angular distributions of fission fragments for the 32S+184W reaction near Coulomb barrier energies are measured. The ex perimental fission excitation function is obtained. The measured fission cross sections are decomposed into fusion-fission, quasi-fission and fast fission contributions by the dinuclear system (DNS) model. The hindrance to completing fusion both at small and large collision energies is explained. The fusion excitation functions of 32S+90,96Zr in an energy range from above to below the Coulomb barrier are measured and analyzed within a semi-classical model. The obvious effect of positive Q-value multi-neutron transfers on the sub-barrier fusion enhancement is observed in the 32S+96Zr system. In addition, the excitation functions of quasi-elastic scattering at a backward angle have been measured with high precision for the systems of 16O+208Pb, 196Pt, 184W, and 154,152Sm at energies well below the Coulomb barrier. Considering the deformed coupling effects, the extracted diffuseness parameters are close to the values extracted from the systematic analysis of elastic and inelastic scattering data. The elastic scattering angular distribution of 17F+12C at 60 MeV is measured and calculated by using the continuum-discretized coupled-channels (CDCC) approach. It is found that the diffuseness parameter of the real part of core-target potential has to be increased by 20% to reproduce the experimental result, which corresponds to an increment of potential depth at the surface re gion. The breakup cross section and the coupling between breakup and elastic scattering are small.

关键词： fusion-fission quasi-fission fusion hindrance fusion enhancement surface diffuseness parameter exotic nuclei

Emission Inventories of Carbon-containing Greenhouse Gases in china and Technological Measures for Their Abatement

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chinese Journal of population,Resources and Environment 2004年第3期2卷 7-13页

作者： Zhuang Yahui, Zhang Hongxun, Wang Xiaoke & Li Changsheng research center for Eco-Environmental sciences, chinese academy of sciences, po box 2871, beijing 700085, china institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH, 03824 U.S.A. research center for Eco-Environmental sciences Chinese Academy of Sciences PO Box 2871 Beijing 100085 China institute for the Study of Earth Oceans and Space University of New Hampshire Durham NH 03824 United States

The report summarizes surveys on carbon inventories and initiatives on sustainable carbon cycling taken by the research center for Eco-Environmental sciences, where the authors work/worked. The first part of the report, which appeared in the preceding issue of this journal, deals with the concept of sustainable carbon cycling, the historic evolution of carbon cycling processes in china, carbon pool enhancement, value addition, carbon sequestration and carbon balance. This very paper, as the second part of the report, covers the results of carbon dynamics modeling, emission inventories of various carbon-containing greenhouse gases and their potential abatement measures.

关键词： sustainable development carbon cycle carbon dynamics modeling emission inventory

Evolutionof Sustainable Carbon Cycling Processes in china

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chinese Journal of population,Resources and Environment 2004年第2期2卷 4-10页

作者： Zhuang Yahui, Zhang Hongxun,Wang Xiaoke & Fang Jinyunresearch center for Eco-Environmental sciences(RCEES),chinese academy of sciences,po box 2871,beijing 100085,chinaDepartment of Urban Ecology,Peking University ,beijing 100871,china research center for Eco-Environmental sciences (RCEBS) Chinese Academy of Sciences PO Box 2871 Beijing 100085 China Department of Urban Ecology Peking University Beijing 100871 China

This report summarizes the surveys on carbon inventories and initiatives on sustainable carbon cycling taken by RCEES. The first part of this report deals with the concept of sustainable carbon cycling, the historical evolution of carbon cycling processes in china, carbon pool enhancement, value addition, carbon sequestration and carbon balance. The second part covers the modeling of carbon dynamics, emission inventories of various carbon containing greenhouse gases and their potential abatement measures.

关键词： sustainable development carbon cycle carbon pool carbon sequestration

Relationship Between Individuals’Epidemic Risk Perception Within Living Space and Subjective Well-Being:Empirical Evidence from china after the First Wave of COVID-19

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chinese Geographical Science 2024年第2期34卷 369-382页

作者： SONG Jiangyu ZHOU Suhong KWAN Mei-po ZHENG Zhong School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China Guangdong Provincial engineering research center for Public Security and Disaster Guangzhou 510275China institute of Space and Earth Information Science the Chinese University of Hong KongHong Kong 999077China Department of Geography and Resource Management the Chinese University of Hong KongHong Kong 999077China institute of Future Cities the Chinese University of Hong KongHong Kong 999077China center for Territorial Spatial Planning and Real Estate Studies Beijing Normal UniversityZhuhai 519000China

It is common to observe the epidemic risk perception(ERP)and a decline in subjective well-being(SWB)in the context of public health events,such as Corona Virus Disease 2019(COVID-19).However,there have been few studies exploring the impact of individuals’ERP within living space on their SWB,especially from a geographical and daily activity perspective after the resumption of work and other activities following a wave of the *** this paper,we conducted a study with 789 participants in urban china,measuring their ERP within living space and examining its influence on their SWB using path *** results indicated that individuals’ERP within their living space had a significant negative effect on their *** density of certain types of facilities within their living space,such as bus stops,subway stations,restaurants,fast food shops,convenience shops,hospitals,and public toilets,had a significantly negative impact on their SWB,mediated by their ERP within living ***,participation in out-of-home work and other activities not only increased individuals’ERP within living space,but also strengthened its negative effect on their SWB.

关键词： subjective well-being epidemic risk perception living space the density of facilities out-of-home activities

Dynamics of risers for earthquake resistant designs

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Petroleum Science 2010年第2期7卷 273-282页

作者： Duan Menglan Wang Yi Yue Zhiyong Estefen Segen Yang Xiaogang School of Naval Architecture and Marine engineering Dalian University of Technology Dalian Liaoning 116024 China Offshore Oil/Gas research center China University of Petroleum Beijing 102249 China Department of Mechanics and engineering Peking University Beijing 100080 China COPPE Federal University of Rio de Janeiro EO.Box 68508 RJ 21945-970 Brazil Design Division CNOOC Engineering Tanggu Tianjin 300452 China

It is well known that no criterion about seismic design for risers is available, and relevant research has not been reported. A comprehensive study of riser dynamics during earthquakes is performed in this paper. A dynamic model for seismic analysis of risers is developed in accordance with the working environment of the risers and the influence of inertia force of the pipelines. The dynamic equations for the developed model are derived and resolved on the basis of the energy theory of beams. Numerical simulation for an engineering project in the Bohai Oil Field, china shows that the fundamental frequency of the riser plays the major role in the seismic responses, and for platforms in shallow water in Bohai Bay, the risers demonstrate a much lower stress response due to prominent differences between the riser frequency and the earthquake wave frequency. The presented model and its corresponding method for seismic analysis are practical and important for riser design resistant to earthquake waves.

关键词： Subsea pipeline riser seismic design dynamic response earthquake wave Hamilton theory

Using Causality Analysis in the Beef Quality Information Tracing

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Using Causality Analysis in the Beef Quality Information Tra...

Saline Water Irrigation Scheduling Through a Crop-Water-Salinity Production Function and a Soil-Water-Salinity Dynamic Model

第三届国际计算机及计算技术农业应用学术会议

作者： Hui Li~1 Daoliang Li~2 Weizhe Feng~3 Weisong Mu~2 Xinxing Li~4 Zetian Fu~(2*) 1 china Agricultural University P.O.box 209 beijing P.R.china 100083 2 College of Information and Electrical engineering china Agricultural University P.O.box 209 beijing P.R.china 100083 3 International College at beijing china Agricultural University beijing P.R.china 100083 4 College of engineering china Agricultural University P.O.box 209 beijing P.R.china 100083

＜正＞Causal relation analysis is a promising application in product quality tracking and *** the quality safety problems in china beef production, the causal relation analysis was introduced into the beef quality safety tracing system and a causal approach-based tracing method was proposed. Considering the implicity,complexity and dynamic characteristics in beef quality safety causal relations, based on its mechanisms,a beef quality safety event representation method was studied based on the extended spanning tree *** the detection algorithm was developed based on an improved minimum spanning tree *** consideration of the time relations,hierarchical relations and causal relation between the beef quality safety events,an approach was proposed for the output of hierarchy view and solution of the causal tracing problems. Finally,through the investigation in the beef production manufactures,the proposed method got sound validation.

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来源： cnki会议评论

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Pedosphere 2007年第3期17卷 303-317页

作者： WANG Yang-Ren KANG Shao-Zhong LI Fu-Sheng ZHANG Lu ZHANG Jian-Hua center for Agricultural Water research in china China Agricultural University Beijing 100083 （China） Department of Water Conservancy engineering Tianjin Agricultural University Tianjin 300384 （China） Agricultural College Guangxi University Nanning 530005 （China） CSIRO Land and-Water GPO Box 1666 Canberra ACT 2601 （Australia） Department of Biology Hong Kong Baptist University Kowloon Tang Hong Kong （China）

Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to obtain the crop water sensitivity index, the salinity sensitivity index, and other parameters. Using data collected during 35 years to calculate the 10-day mean precipitation and evaporation, the variation in soil salinity concentrations and in the yields of winter wheat and cotton were simulated for 49 irrigation scheduling that were combined from 7 irrigation schemes over 3 irrigation dates and 7 salinity concentrations of saline irrigation water (fresh water and 6 levels of saline water). Comparison of predicted results with irrigation data obtained from a large area of the field showed that the model was valid and reliable. Based on the analysis of the investment cost of the irrigation that employed deep tube wells or shallow tube wells, a saline water irrigation schedule and a corresponding strategy for groundwater development and utilization were proposed. For wheat or cotton, if the salinity concentration was higher than 7.0 g L-1 in groundwater, irrigation was needed with only fresh water; if about 5.0 g L-1, irrigation was required twice with fresh water and once with saline water; and if not higher than 3.0 g L-1, irrigation could be solely with saline water.

关键词： crop-water-salinity production function irrigation scheduling saline water irrigation water-salinity dy- namic model