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Simulation of 1991-2.05 Meiyu seasons in the Yangtze-Huaihe region using BCC_RegCM 1.0

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Chinese Science Bulletin 2010年第11期55卷 1077-1083页

作者： HU YaMin1,2.3. DING YiHui4 1 institute of Tropical and Marine meteorology,{2. Meteorological Administration, Guangzhou 510080,{2. 2.Guangdong Climate Center, Guangzhou 510080,{2. 3.Chinese Academy of Meteorological Sciences, Beijing 100081,{2. 4 National Climate Center,{2. Meteorological Administration, Beijing 100081,{2. institute of Tropical and Marine meteorology China Meteorological Administration Guangzhou 510080 China Guangdong Climate Center Guangzhou 510080 China Chinese Academy of Meteorological Sciences Beijing 100081 China National Climate Center China Meteorological Administration Beijing 100081 China

By using BCC_RegCM 1.0 (RegCM for short) from Beijing Climate Center (BCC), china Meteorological Administration (CMA), the Meiyu season characters over the Yangtze-Huaihe region during 1991-2.05 are simulated. The major conclusions of this study may be summarized as the following: (1) RegCM can reproduce the interannual variation and the spatial distribution of the summertime precipitation and temperature in the Yangtze-Huaihe region. (2. By use of a generalized Meiyu criterion and in accordance with model-calculated precipitation and temperature, the Meiyu onset and ending date have been determined. Compared with the observation, RegCM can simulate the interannual variation of the Yangtze-Huaihe Meiyu with preferable capability for most of the normal Meiyu years (such as 1995, 1997, 2.00, 2.01, 2.02.and 2.04), especially for the rich Meiyu years of 1996, 1998 and 1999. (3. In terms of the average simulation for the recent 15 years, the timings of onset and ending of Meiyu occur on June 1 and July 13. respectively, which are earlier than the climatological observation. For duration, Meiyu persists for 3.1}d, 3.d shorter than the observation. The index of Meiyu intensity is 2.45, while the climatological one is 3.00. Therefore, RegCM is capable of simulating the climatological Meiyu duration and intensity, while the capability of simulating the onset and ending date of Meiyu still needs to be improved.

关键词：梅雨季节模拟计算长江气候观测发病时间强度指数中国气象局空间分布

Electrode Characteristics of MmNi_5-based Alloys for Nickel-Metal Hydride Batteries

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Journal of Materials Science & Technology 1994年第4期10卷 310-312页

作者： Mingming GENG (dept. of Precision Alloy, Central Iron & Steel Research institute, Beijing, 100081.{2.) Central Iron and Steel Research Inst Beijing China

Negative electrodes of the Ni-metal hydride battery were made from hydrogen storage alloy Mm0.9Ti0. 1Ni3. 9Mn0.4Co0.4Al0.3.mod fied by coating with Ni or mixing with Co powder. The cell volume expansion of hexagonal structure was about 12.% after coating with 11 % Ni on the alloy Surface,When this alloy was mixed with Co powder. the discharge capacity and the utilization efficiency of the hydrogen storage alloy increased. When the alloy was coated with 11 wt-% Ni and also mixed with 10 wt-% Co powder. the capacity decay for a small sealed cylindrical cell (AA size. 1 Ah) was only about 4 % after 2.0 cycles

关键词： Ni Met Electrode Characteristics of MmNi5-based Alloys for Nickel-Metal Hydride Batteries PVA

SENSITIVE NUMERICAL SIMULATION AND ANALYSIS OF RAINSTORM USING NESTED WRF MODEL

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Journal of Hydrodynamics 2006年第5期18卷 578-586页

作者： WANG Shu-chang HUANG Si-xun LI Yi institute of meteorology PLA University of Science and Technology Nanjing 211101 China

Nowadays, the nested grid model is widely used to increase the resolution of numerical model. An attempt to investigate the influence of the newly developed nesting technique of WRF model on the mesoscale numerical simulation of severe storm is described in this article. The results of sensitivity tests infer that the WRF model give more accurate and vivid prediction of severe storm with nesting scheme. As is shown in the tests, simulating value of the precipitation centers using nesting scheme are larger than those without using nesting scheme, which indicates that the simulating precipitation of nested storm is closer to the real rainfall. And there is obvious improvement of distribution of rain area and position of precipitation centers. According to the high resolution output data of the WRF model, deep and detailed analysis of characters of the mesoscale system that triggers the rainstorm is reported in this article, and the thermal and dynamical characters of this Meiyu front severe storm are also discussed.

关键词： WRF nesting numerical simulation mesoscale analysis

Water resources optimization and eco-environmental protection in Qaidam Basin

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Journal of Geographical Sciences 2001年第2期11卷 231-238页

作者： FANG Chuang-lin~1, BAO Chao~2.(1. institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, china 2. {2. of Geography, Peking University, Beijing 100871, china) institute of Geographic Sciences and Natural Resources Research CAS dept. of Geography Peking University

In order to realize sustainable development of the arid area of Northwest china, rational water resources exploitation and optimization are primary prerequisites. Based on the essential principle of sustainable development, this paper puts forward a general idea on water resources optimization and eco-environmental protection in Qaidam Basin, and identifies the competitive multiple targets of water resources optimization. By some qualitative methods such as Input-output Model & AHP Model and some quantitative methods such as System Dynamics Model & Produce Function Model, some standard plans of water resources optimization come into being. According to the Multiple Targets Decision by the Closest Value Model, the best plan of water resources optimization, eco-environmental protection and sustainable development in Qaidam Basin is finally decided.

关键词： water resources optimization Multiple Targets Decision by the Closest Value Model eco-environmental protection Qaidam Basin

QUADRATIC PROGRAMMING NEURAL NETWORK BASED INTEGRATED SPACE-TIME INTERFERENCE SUPPRESSION IN CDMA SYSTEMS

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Journal of Electronics(china) 2001年第2期18卷 140-146页

作者： Song Rongfang Bi Guangguo(dept. of Radio Engineering, Southeast University, nanjing 2.0096) (dept. of Telecom. Eng., nanjing institute of Posts & Telecom., nanjing 2.0003. dept.of Radio Engineering Southeast UniversityNanjing 210096 dept.of Telecom.Eng. Nanjing Institute of Posts & Telecom.Nanjing 210003 dept.of Radio Engineering Southeast UniversityNanjing 210096

Quadratic programming models for integrated space-time interference suppression in CDMA systems are proposed in this paper. The models integrate the advantages of smart antenna and RAKE receiver, mitigate multiuser access interference (MAI) and interchip interference (ICI),and combine multipath components. The zero-forcing conditions are derived. Neural network implementation of the models is also studied.

关键词： CDMA Space-time processing Smart antenna Optimization Neural network

Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

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Science china Earth Sciences 2006年第z1期49卷 135-145页

作者： LAI Geying, YU Ge & GUI Feng nanjing institute of Geography & Limnology, Chinese Academy of Sciences, nanjing {3.0008, china The Graduate School of the Chinese Academy of Sciences, Beijing 10003., china Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi Normal University, Nanchang 3.00{3., china 1. nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China2. The Graduate School of the Chinese Academy of Sciences Beijing 100039 China3. Key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang 330027 China

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2.02.has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2.01 to 2.02. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2.00t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53. and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 3.% and 16%, and sewerage in both forms of point source and non-point source are TN 3.% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

关键词： Taihu Basin, nutrients, catchment resource inputs, SWAT model, simulation.

Identifying the northernmost summer monsoon location in East Asia

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Progress in Natural Science:Materials International 2007年第7期17卷 812-820页

作者： Hu Haoran~1 Qian Weihong~(2.*) (1.institute of Plateau meteorology,CMA,Chengdu 610071,{2. 2.Monsoon and Environment Research Group,School of Physics,Peking University,Beijing 100871,{2.) [a]institute of Plateau meteorology CMA Chengdu China [b]Monsoon and Environment Research Group School of Physics Peking University Beijing China

An integrated index which can be used to indicate the advance of subtropical summer monsoon in East Asia has been proposed in this *** index was comhined by three variables including precipitation,wind and pseudo-equivalent potential tempera- *** northernmost summer monsoon location(NSML)was identified by using this index *** was found that the NSML ex- perienced an interdecadal shift in the period 1977—1979 based on the annual index analysis from 1961 to 2.01.A comparison of the NSML with other four summer monsoon indices has also been *** result showed that the NSML could well represent the interan- nual and interdecadal variability of summer monsoon precipitation in North china(beyond 3.°N),while other four indices could well indi- cate the precipitation anomalies of East Asian summer monsoon along the Yangtze River valley(around 3.°N).

关键词： subtropical summer monsoon northernmost location index,interdecadal variability East Asia

Statistical characteristics of the double ridges of subtropical high in the Northern Hemisphere

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Science Bulletin 2005年第20期 82-87页

作者： ZHAN Ruifen1,2.3. LI Jianping1 & HE Jinhai2. 1. State Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics (LASG), institute of Atmos- pheric Physics, Chinese Academy of Sciences, Beijing 10002., china 2. Department of Atmospheric Sciences, institute of meteorology, Nan- jing University of Information Science and Technology, nanjing 21004., china 3. Graduate School of the Chinese Academy of Sciences, Beijing 10003., china

The generality and some climatological charac- teristics of the double ridge systems of subtropical high (SH) are investigated statistically by using the daily NCEP/NCAR reanalysis data from 1958 to 1998. The results show that the SH double-ridge event is a common phenomenon in the Northern Hemisphere, with the distinct seasonal and re- gional features, that is, the majority of SH double-ridge geneses concentrate over the eastern North India Ocean- western North Pacific as well as the central North Pacific in the period from mid-July to mid-September. Especially over the western North Pacific subtropics, the SH double-ridge events are extremely active. It is found that the life cycle of most double-ridge events of western Pacific subtropical high (WPSH) is shorter but some still last longer. The WPSH dou- ble-ridge events occur most frequently from July to Septem- ber, while there is a paucity of occurrences during Novem- ber-March. Also, it is shown that the WPSH double-ridge events have a strong interannual variation with a certain periodicity which possesses a remarkably abrupt change in the mid-1970s. Additionally, the relationship between the WPSH double ridges and the meridional movement of WPSH is discussed.

关键词： subtropical high double ridges statistical characteristics meridional movement.

Simulation and Prediction of Soil Organic Carbon Dynamics in Jiangsu Province Based on Model and GIS Techniques

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Journal of Integrative Agriculture 2003年第9期 67-73页

作者： SHEN Yu 1, HUANG Yao 1,2. , ZONG Liang gang 1, ZHANG Wen 1, XU Mao 3.and LIU Lin wang 3. ( 1College of Resources and Environmental Sciences, nanjing Agricultural University, nanjing 2.0095, P.R.{2. 2.3. of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., P.R.{2. 3.iangsu Agricultural and Forestry Department, nanjing 2.003., P.R.{2.)

Based on the databases of soils, meteorology, crop production, and agricultural management, changes in the soil organic carbon (SOC) of agro ecosystems in Jiangsu Province were simulated by using a soil organic carbon model with a linkage of GIS. Four data sets of soil organic carbon measured from various field experiments in Jiangsu Province were used to validate the model. It was demonstrated that the model simulation in general agreed with the field measurements. Model simulation indicated that the SOC content in approximately 77% of the agricultural soils in Jiangsu Province has increased since the Second National Soil Survey completed in the early 1980s. Compared with the values in 1985, the SOC content in 2.00 was estimated to increase by 1.03.0 g kg 1 for the north and the coastal areas of the province, and by 3.55.0 g kg 1 for the region of Tai Lake in the south. A slight decrease (about 0.51.5 g kg 1 ) was estimated for the central region of Jiangsu Province and the nanjing Zhenjiang hilly area. Model prediction for 2.10 A.D. under two scena rios, i.e., with 3. and 50% of the harvested crop straw incorporation, suggested that the SOC in Jiangsu Province would increase, and thus that the agricultural soils would have potential as organic carbon storage. The incorporation of crop straw into soils is of great benefit to increase soil carbon storage, consequently to benefit the control of the rise of atmospheric CO 2.concentration and to maintain the sustainable development of agriculture.

关键词： Soil Organic carbon Model GIS Jiangsu Province