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Distribution of possible sunshine durations over rugged terrains of china

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Progress in Natural Science:Materials International 2003年第10期 41-44+81页

作者： ZENG Yan 1, QIU Xinfa 2.*, MIAO Qilong 2.and LIU Changming 1(1. institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101,{3. 2. Department of Geography,{2., nanjing 21004.,{3.) institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography Nanjing Institute of Meteorology Nanjing 210044 China

Based on the digital elevation model (DEM), a new model for calculating possible sunshine duration (PSD) is completely described. Using this model, monthly PSD with resolution of 1 km×1 km for the rugged topography of china is calculated. Results suggest that terrain has robust effect on PSD, particularly in winter when a lower sun elevation angle exists. Besides, the proposed model taking the DEM data as the input has an ability to process mass of data and is applicable to satellite image processing platforms or Geographic Information System (GIS). The PSD (in hours) is provided in the same way as other kinds of spatial information and can be employed as basic geographic data for relevant studies as well.

关键词： possible sunshine duration (PSD) rugged terrains spatial distributions digital elevation model (DEM).

Distributed modeling of the beginning and ending dates and durations of limited temperatures over the rugged terrain of Chongqing

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Progress in Natural Science:Materials International 2009年第12期19卷 1739-1746页

作者： Xinfa Qiu~a,Guoping Shi~a,Yan Zeng~(b,*),Zongya Bian~a,Jingmei Wei~c a Department of GIS,School of Remote Sensing,nanjing University of Information Science & Technology,nanjing {2.,{3. b Jiangsu institute of Meteorological Sciences,nanjing 2.0008,{3. c Jinling College,nanjing University,nanjing 2.0089,{3. [a]Department of GIS School of Remote Sensing Nanjing University of Information Science & Technology Nanjing 210044 China [b]Jiangsu institute of Meteorological Sciences Nanjing 210008 China [c]Jinling College Nanjing University Nanjing 210089 China

A physically based empirical model was established for the beginning and ending dates(BED) of limited *** used were daily mean temperatures from 3. conventional stations in the Chongqing region,measured from 1961 to *** this model in combination with the distributed modeling results of monthly mean temperatures,we developed a method for creating a distributed simulation of the BED and durations of limited temperatures in the rugged terrain of *** distribution maps were generated at a resolution of 100×100 m for the BED and durations of the limited temperatures of 0,10,15 and *** suggest that the distributed model is able to successfully reveal the macroscopic trends and local *** the modeled BED,the mean absolute bias error is 0.6-2.4 d. Cross-validation and case-year tests show mean absolute bias errors of 1.3.2.8 d and 0.7-2.5 d,*** shows that the simulation results are consistent with the field *** implies that the simulations are as good as observations,thus providing a viable technique for simulating mountainous heat resources using conventional meteorological data.

关键词： Distributed modeling Chongqing Limited temperature Beginning and ending date

Construction of Optimal Truncated Low-Dimensional Dynamical systems directly from PDEs

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Communications in Nonlinear Science and Numerical Simulation 1998年第1期3卷 1-5页

作者： Hongliang ZHAO, Chuijie WU(LNM, institute of Mechanics, CAS, Beijing, 100080) (Air Force institute of {2., {3., 2.1101) Email: cjwu@*** LNM Institute of Mechanics CAS Beijing 100080 China Air Force institute of meteorology Nanjing 211101 China

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关键词： low dimensional dynamical system partial differential equations optimization

NUMERICAL EXPERIMENTS ABOUT GROWTH OF THE ENERGY OF DISTURBANCE IN A BAROCLINIC FLOW

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Journal of Hydrodynamics 2008年第4期20卷 499-506页

作者： TENG Jia-jun HUANG Si-xun ZHANG Liang School of Science PLA University of Science and Technology Nanjing 211101 China Shanghai institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China institute of meteorology PLA University of Science and Technology Nanjing 211101 China

This article is concerned with the growth of energy of disturbances in a baroclinic flow within a finite time period. The implicit difference scheme was applied to the linearized vorticity equation, and the disturbance energy was computed for three kinds of vertical shears. It turns out that all the disturbance energy rapidly increases initially, and during the succeeding period there are several stages of growth and decay of energy of disturbances, and from a certain time on, all the disturbance energy begins to decrease.

关键词： implicit difference scheme vertical shear linearized potential vorticity equation disturbance energy Couette flow

STUDY　OF　INTERACTION　BETWEEN　VORTICES　AND　A　FREE　SURFACE　PART　Ⅱ：INTERACTION　OF　DOUBLE　VISCOUS　VORTEX　DIPOLES　WITH　A　FREE　SURFACE

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Journal of Hydrodynamics 1995年第1期7卷 17-32页

作者： Wu Chui-jie Tan Bo-yan (Air Force institute of meteorology,{2. 2.1101 P. R. china)Ma Hui-yang(Graduate School of Academia Sinica, Beijing 10003. P. R. china)( Air Force Inst of meteorology Nanjing China

In this paper the VOF (Volume of Fluid) method is used to numerically study the interaction of double viscous vortex dipoles with free surface in a two dimensional incompressible flow field. From the results of this research, it is found that the general consequence of the interaction is qualitatively equivalent to the problem of a single vortex dipole interacts with a free surface.

关键词： vortex motion free surface computational fluid mechanics.

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中文Web概念挖掘系统设计与测评

上海交通大学学报 2003年第S1期37卷 207-211页

作者：章成志侯汉清丁璇南京工业职业技术学院工商管理系南京210016 南京农业大学信息管理系南京2010095 金陵科技学院图书馆南京210001

Web概念挖掘系统的总体设计思想是 :基于《中图法》知识库的主题标引和自动分类 ,即依据标引源权重方案进行文本的概念提取 ,利用语义相似度算法进行文本的自动分类 .本文简要介绍了概念挖掘系统的基本情况 ,并进行了 4种加权标引方案... 详细信息

Web概念挖掘系统的总体设计思想是 :基于《中图法》知识库的主题标引和自动分类 ,即依据标引源权重方案进行文本的概念提取 ,利用语义相似度算法进行文本的自动分类 .本文简要介绍了概念挖掘系统的基本情况 ,并进行了 4种加权标引方案的比较和性能的测评 .

关键词：概念挖掘自动标引主题标引自动分类

NUMERICAL SIMULATIONS OF SEA ICE WITH DIFFERENT ADVECTION SCHEMES

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Journal of Hydrodynamics 2011年第3期23卷 372-378页

作者： LIU Xi-ying State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China institute of meteorology PLA University of Science and Technology Nanjing 211101 China

Numerical simulations are carried out for sea ice with four different advection schemes to study their effects on the simulation results. The sea ice model employed here is the Sea Ice Simulator （SIS） of the Geophysical Fluid Dynamics Laboratory （GFDL） Modular Ocean Model version 4b （MOM4b） and the four advection schemes are, the upwind scheme originally used in the SIS, the Multi-Dimensional Positive Advection （MDPA） scheme, the Incremental Remapping Scheme （IRS） and the Two Step Shape Preserving （TSSP） scheme. The latter three schemes are newly introduced. To consider the interactions between sea ice and ocean, a mixed layer ocean model is introduced and coupled to the SIS. The coupled model uses a tri-polar coordinate with 12.x65 grids, covering the whole earth globe, in the horizontal plane. Simulation results in the northern high latitudes are analyzed. In all simulations, the model reproduces the seasonal variation of sea ice in the northern high latitudes well. Compared with the results from the observation, the sea ice model produces some extra sea ice coverage in the Greenland Sea and Barents Sea in winter due to the exclusion of ocean current effects and the smaller simulated sea ice thickness in the Arctic basin. There are similar features among the results obtained with the introduced three advection schemes. The simulated sea ice thickness with the three newly introduced schemes are all smaller than that of the upwind scheme and the simulated sea ice velocities of movement are all smaller than that of the upwind scheme. There are more similarities shared in the results obtained with the MPDA and TSSP schemes.

关键词： advection scheme sea ice simulation

Pan-sharpening:a fast variational fusion approach

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Science china(Information Sciences) 2012年第3期55卷 615-625页

作者： ZHOU ZeMing1, LI YuanXiang2., SHI HanQing1, MA Ning1 & SHEN Ji2.1institute of {3., PLA University of Science and Technology, {2. 2.1101, china 2.chool of Aeronautics and Astronautics, Shanghai JiaoTong University, Shanghai 2.02.0, china 1. institute of meteorology PLA University of Science and Technology Nanjing 211101 China2. School of Aeronautics and Astronautics Shanghai JiaoTong University Shanghai 200240 China

A fast variational fusion model based on partial differential equations (PDEs) is presented for pansharpening. The functional framework consists of several energy terms. The gradient energy term is created by calculating the gradient vector field of the panchromatic image and the geometry of the pan is injected into the multi-spectral bands. The radiometric reduction energy term and the channel correlation energy term are defined to decrease the radiometric distortion and preserve the correlation of multi-spectral channels while enforcing the inter-bands coherence. Inspired by the shock-filtering model, an inverse diffusion term for image enhancement is put to PDEs which are deduced by minimizing the energy functional. In comparison with the state-of-the-art fusion approaches based on `a trous wavelet and non-sampled contourlet, our model can obtain the fused image with a high spatial or spectral quality by adjusting the weight coefficients of the energy terms. It can also achieve a rather good trade-off between the spatial resolution improvement and the spectral quality preserving. Our model's computational complexity for one time step is only O(N).

关键词： remote sensing image pan-sharpening energy functional fast variational fusion

Improved Prediction of Turbulent Separated Flow with a Low-Reynolds-Number Nonlinear k-∈Model

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Communications in Nonlinear Science and Numerical Simulation 1997年第3期 35-39页

作者： Guangsheng ZHU & Chuijie WU (Inst. of Mech., nanjing Univ. of Science and Technology, nanjing 2.0094,{2.) (Air Force institute of meteorology, nanjing 2.1101,{2.) E mail: wucj@***

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关键词： nonlinear turbulence model turbulent flow  k-∈ turbulence model