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Diagnosis of a Severe Rainstorm Event Induced by Eastly Wave and Vortex in Off Southeast Coast of china

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高原气象 2009年第5期28卷 1058-1066页

作者： ZHENG Feng1-3(1.Chinese Academy of Meteorological sciences,Beijing 100081,china 2.nanjing university of information science & technology,nanjing 210044,china 3.Wenzhou Meteorological Bureau,Wenzhou 325027,china) Chinese Academy of Meteorological sciences 北京 100081

Using the NCEP reanalysis at 1°×1° resolution in conjunction with satellite imagery,a study is undertaken of easterly wave related rainstorm events on August 3~4,2001 in seaboards between northern Fujian and southern Zhejiang,expounding the scheme for computing helicity,and exploring the rainstorm evolution and the genesis of the Yandang mountains-triggered a meso-vortex(Duan and Chen,2005) by means of helicity and Q vector ***,MM5V2 is employed to simulate the easterly wave caused meso-vorte...

关键词： Easterly wave Meso-vortex Helicity Q vector MM5 modeling

Turbulent intensity and its similarity function over an Inner Mongolian grassland during spring

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science china Earth sciences 2010年第5期53卷 773-780页

作者： YUE Ping1,2,3, NIU ShengJie2, HU YinQiao4 & ZHANG Qiang1 1 Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province, Key Laboratory of Arid Climate Change and Reducing Disaster of CMA, Institute of Arid Meteorology, CMA, Lanzhou 730020, china 2 nanjing university of information science and technology, nanjing 210044, china 3 Zhangye National Meteorological Observatory, Zhangye 734000, china 4 Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of science, Lanzhou 730000, china Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province Key Laboratory of Arid Climate Change and Reducing Disaster of CMA Institute of Arid Meteorology CMA Lanzhou China nanjing university of information science and technology Nanjing China Zhangye National Meteorological Observatory Zhangye China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Science Lanzhou China

Macroscopic reason for the development of turbulences in fluid is the conjunction action of velocity and temperature shears. We use the 2008 spring flux observations in the surface layer over Inner Mongolian grassland, obtain the similarity functions of turbulent intensity under different stratification stability conditions, and calculate the clear day turbulent intensity in the spring, which is then analyzed and compared with the observed values of turbulent intensity. The results show that in the Inner Mongolian grassland, under the condition of spring unstable stratification of the surface layer, dependence of the similarity function of turbulent intensity on stratification stability follows a "2/3 power law". The structural function is a constant under the neutral stratification condition, and complicated under the stable condition. The calculated turbulent intensity has a close correlation with the observed one, which verifies the accuracy of the similarity functions and the suitability of the theorem of turbulent intensity in the grassland region.

关键词： turbulent intensity variance of velocity similarity function grassland

Surface N Balances in Agricultural Crop Production Systems in china for the Period 1980-2015

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Pedosphere 2008年第3期18卷 304-315页

作者： SUN Bo SHEN Run-Ping A. F. BOUWMAN Institate of Soil science Chinese Academy of Sciences Nanjing 210008 （China） nanjing university of information science and technology Nanjing 210044 （China） National Institute for Public Health and the Environment P. O. Box 303 3720 AH Bilthoven （The Netherlands）

Surface nitrogen(N) balances for china's crop production systems were estimated using statistical data collected from 1980 to 2004 at the national and provincial scale and from 1994 to 1999 at the county *** was a surplus N balance throughout these periods,but the surplus was nearly stable in recent *** using nonseasonal Box-Jenkins model or exponential models show that the N surplus for the total cultivated land in china was likely to increase from 142.8 kg ha?1 in 2004 to 168.6 kg ha-1 in *** N balance surplus in the more developed southeastern provinces was the largest,and was slightly less in the central region,which caused the nitrate pollution in the ground *** N surplus was much less in the western and northern provinces because of lower synthetic fertilizer *** region with high N risk includes Beijing Municipality and Jiangsu,Zhejiang,Fujian,Guangdong,Hubei,and Shandong provinces for *** projections suggested that 15 provinces(or municipalities) in the middle and southeastern part of china except Jiangxi and Shanxi provinces would become the high-risk region by *** level of economic development,transportation,and labor force condition had an important e?ect on the N balance surplus at the county level,but the last two factors showed remarkable impact at the provincial *** decrease the nonpoint pollution(Npp) risk from crop production,the authors suggested to reduce the target level for national grain self-suflciency to 90%-95% and change the regional structure of grain production by moving some of the future grain production from the high Npp risk areas of eastern china to parts of the central and western provinces where the Npp risk was much less.

关键词：中国农业环境污染氮平衡

Evaluation on the Developmental Level of Circular Economy in Jiangsu Province

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Asian Agricultural Research 2011年第3期3卷 34-38页

作者： XIAN Li-hua1,MEN Ke-pei2,ZHANG Na2 1.nanjing Radio and TV university,nanjing 210002,china 2.nanjing university of information science & technology,nanjing 210044,china nanjing Radio and TV university nanjing university of information science & technology

Based on the brief description of the developmental status of social economy in Jiangsu Province,the index system including 16 indexes contained in 5 subsystems is established according to the statistics from Jiangsu Statistical Yearbook-2009,the practical situation of Jiangsu Province and the connotation of circular *** developmental trends of circular economy of 13 prefecture-level cities in Jiangsu Province are comprehensively evaluated by using the improved extreme value treatment,analytic hierarchy process(AHP),comprehensive evaluation of herdsman and comprehensive evaluation model of grey *** results show that the developmental level of circular economy in Jiangsu Province varies hugely in different areas,the difference of the comprehensive score between the crest value and minimum value is *** the end,in view of the problems in the development of circular economy,the countermeasures and suggestions on establishing and improving the management of circular economy,the operation and supervision mechanism;accelerating the industrial transformation and intensifying resource saving and comprehensive use of resource.

关键词： Jiangsu Province Circular economy AHP Comprehensiv

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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science china(information sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2,LI Gang 3 & GENG HuanTong 1 1 School of Computer and Software,nanjing university of information science & technology,nanjing 210044,china 2 Network information Center,nanjing university of information science & technology, nanjing 210044,china 3 School of Mathematics and Physics,nanjing university of information science & technology,nanjing 210044,china School of Computer and Software Nanjing University of Information Science & Technology Nanjing China Network information Center Nanjing University of Information Science & Technology Nanjing China School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing China

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

Basin filling algorithm for the circular packing problem with equilibrium behavioral constraints

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science china(information sciences) 2010年第5期53卷 885-895页

作者： LIU JingFa1& LI Gang2 1School of Computer and Software, nanjing university of information science & technology, nanjing 210044, china 2School of Mathematics and Physics, nanjing university of information science & technology, nanjing 210044, china School of Computer and Software Nanjing University of Information Science & Technology Nanjing China School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing China

With the background of the satellite module layout design, the circular packing problem with equilibrium behavioral constraints is a layout optimization problem and NP-hard problem in math. For lack of a powerful optimization method, this problem is hard to solve. The energy landscape paving (ELP) method is a class of stochastic global optimization algorithms based on the Monte Carlo sampling. Based on the quasiphysical strategy and the penalty function method, the problem is converted into an unconstrained optimization problem. Here by combining the improved ELP method, the gradient method based on local search and the heuristic configuration update mechanism, a new global search algorithm, basin filling algorithm, is put forward. The numerical results show that the proposed algorithm is effective to solving the circular packing problem with equilibrium behavioral constraints, and is easy to be popularized to other layout optimization problems.

关键词： equilibrium behavioral constraints packing problem layout optimization

Research into a theoretical mode of coherent structures in the wall region of a turbulent boundary layer induced by a wall local disturbance

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Progress in Natural science:Materials International 2009年第9期19卷 1119-1124页

作者： Changgen Lua,*, Qinjuan Qi b a College of Atmospheric sciences, nanjing university of information science & technology, nanjing 210044, china b College of Public Management, nanjing university of information science & technology, nanjing 210044, china College of Atmospheric sciences Nanjing University of Information Science & Technology Nanjing 210044 China College of Public Management Nanjing University of Information Science & Technology Nanjing 210044 China

The idea of applying direct numerical simulation (DNS), a theoretical mode of coherent structures in the wall region of a turbulent boundary layer, has been discussed in the literature. The various aspects of the formation mechanism of the coherent structures agree well with both DNS and experimental results. In addition, a close relationship has been found between the evolutional characteristics and factors such as the magnitude and structural distribution of the wall local impulse disturbance, and the amount of energy a local disturbance introduces into the wall region. Moreover, these parameters play key roles in the formation of coherent structures near the wall region of a turbulent boundary layer. Therefore, the wall local impulse disturbance provides a theoretical model for triggering the formation of coherent structures in the wall region of a turbulent boundary layer.

关键词： Turbulent boundary layer Wall region Coherent structure Local disturbance

Resolution method for overlapping peaks based on the fractional-order differential

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science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2 & ZHENG Gang2 1 College of information & Control, nanjing university of information science & technology, nanjing 210044, china 2 College of Automation Engineering, nanjing university of Aeronautics and Astronautics, nanjing 210016, china College of information & Control Nanjing University of Information Science & Technology Nanjing China College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

EXISTENCE OF WEAK SOLUTIONS TO A DEGENERATE STEAD-STATE SEMICONDUCTOR EQUATIONS

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Acta Mathematica Scientia 2011年第3期31卷 960-968页

作者：吴斌 College of Mathematics and Physics nanjing university of information science and technology

In this paper, we consider a degenerate steady-state drift-diffusion model for semiconductors. The pressure function used in this paper is （）（s） = s~α（α 〉 1）. We present existence results for general nonlin... 详细信息

关键词： steady-state degenerate semiconductor equations drift-diffusion model