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Features of aerosol optical depth and its relation to extreme temperatures in China during 1980–2.01

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Acta Oceanologica Sinica 2011年第2期30卷 33-45页

作者： HU Ting SUN Zhaobo LI Zhaoxin Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Scienceand Technology Nanjing 210044 China The Department of Atmospheric science Nanjing University of Information Science andTechnology Nanjing 210044 China Laboratoire de Meteorologie Dynamique CNRS France

Based on Total Ozone Mapping Spectrometer （TOMS） monthly aerosol optical thickness （AOT） measurements in 1980–2.01 a study is made of space/time patterns and difference between land and sea of AOT 0.50 μm thick over China,which are put into correlation analysis with synchronous extreme temperature indices （warm/cold day and night）.Results suggest that 1） the long-term mean AOT over China is characterized by typical geography,with pronounced land-sea *** AOT has significant seasonality and its seasonal difference is diminished as a function of latitude.2. On the whole,the AOT displays an appreciably increasing trend,with the distinct increase in the eastern Qinghai-Tibetan plateau and SW China,North China,the mid-lower Changjiang （MiLY） valley as well as the South China Sea,but marginal decrease over western/northern Xinjiang and part of South China.{2. The AOT over land and sea is marked by conspicuous intra-seasonal and -yearly oscillations,with remarkable periods at one-,two-yr and more （as interannual periods）.4） Land AOT change is well correlated with extremely temperature ***,the correlations of AOT to the extreme temperature indices are more significant in Eastern China with 110 ° E as the *** high-correlation regions are along the Southern China coastline,the Loess plateau and the Sichuan Basin,and even higher in North China plain and the mid-lower Changjiang River reaches.5） Simulations of LMDZ-regional model indicate that aerosol effects may result in cooling all over China,particularly in Eastern *** contribution of aerosol change may result in more decrease in the maximum temperature than the minimum,with decrease of 0.11/0.08 K for zonal average,respectively.

关键词： aerosol optical thickness extreme temperature index space/time pattern trend correlation

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 meteorology,{2.,{3., 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

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

The reconstruction and interpretations of lake status at 6 ka and 18 ka *** inland mainland Asia

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Chinese science Bulletin 1998年第14期43卷 1145-1157页

作者： QIN Boqiang 1, SHI Yafeng 1 and YU Ge 2. 3.1. nanjing {2. of Geography & Limnology, Chinese Academy of {2.s, nanjing 2.0008, China 2. Dynamic Palaeoclimatology, Lund university, PO Box 117, S 2.1 00, Lund, Sweden 3. Department of nanjing institute of Geography & Limnolagy Chinese Academy of Sciences Nanjing China Dynamic Palaeoclimatology Lund University Lund Sweden Department of Geology and Ocean sciences Nanjing University Nanjing China

By means of survey of literature through compilations of sedimentological, biogeological and geomorphologic data, the inland lake level changes in arid or semi arid mainland Asia at 6 and 18 ka B.P. have been reconstructed. The results showed that the lakes from western and northwestern Asia were characterized by very high water levels at 18 ka B.P., but low or intermediate water stands at 6 ka B.P. The high lake level in this region was associated with the southward displacement of westerlies, therefore, the extent of the high lake stand indicated the southern flank of westerlies during the glaciation. Conversely, the lakes from the eastern and southern Asia registered comparative low levels at 18 ka B.P. and significantly high one at 6 ka B.P. The lowering of lake level at 18 ka B.P. was caused by the weakened summer monsoon and the high lake level at 6 ka B.P. by the enhanced summer monsoon induced by the enlarged thermal contrast between land and ocean. The extent of high lake levels indicated the northern boundary of monsoon expansion. Between the above two regions, there is a climatic transitional zone in the Central Asia where the lake behavior was close to that in southeastern Asia at 6 ka B.P. but became similar to that in northwestern Asia at 18 ka B.P. Thus this zone became a transitional sector from the monsoon to the westerlies.

关键词： lake status inland mainland Asia westerlies monsoon.

A novel multicluster V-MIMO PCR scheme in large-scale Ad Hoc networks

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science China(Information sciences) 2010年第10期53卷 2097-2105页

作者： ZHOU Yao, CAI YueMing & PAN ChengKang Department of Wireless Communication, institute of Communications Engineering, pla university of science and technology, {2. 2.0007, China 1. Department of Wireless Communication Institute of Communications Engineering PLA University of Science and Technology Nanjing 210007 China

A multicluster packet collision resolution (PCR) scheme is a kind of recently proposed virtualMIMO techniques. In existing multicluster PCR schemes, a large-scale wireless Ad Hoc network is divided into clusters and the single cluster PCR scheme is applied independently to resolve collisions in each cluster. However, there are still some flaws in existing multicluster PCR schemes. In this paper, by presenting a concise theoretical analysis model and a new CNS algorithm, a novel multicluster PCR scheme is proposed. Analysis and simulation results show that the proposed scheme can obtain high performance gain with low complexity. The proposed scheme is more robust and applicable than existing schemes.

关键词： packet collision resolution virtual-MIMO cooperative communication cooperative nodes selection

Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1,2., Zhang Yong3.and Long Guilu1,2.1. Key Laboratory for Atomic and Molecular Nanosciences, and Department of Physics, Tsinghua {2., Beijing 100084, China 2. Center of Quantum Information science and {3., Tsinghua National Laboratory for information science and {3., Beijing 100084, China 3. institute of Physics, School of sciences, Beijing {2. of Posts and Telecommunications, Beijing 100876, China) Key Laboratory for Atomic and Molecular Nanosciences and Department of Physics Tsinghua University Beijing 100084 China Center of Quantum Information science and technology Tsinghua National Laboratory for information Science and Technology Beijing 100084 China institute of Physics School of Sciences Beijing University of Posts and Telecommunications Beijing 100876 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3. namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.

Bionic Design and Finite Element Analysis of Elbow in Ice Transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2., Xiuhua Sui~3. Linjing Xiao~3.1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education, China), Shandong {2. of science and {2., Qingdao 2.6510, P. R. China 2. School of Architecture, Tsinghua {2., Beijing 100084, P. R. China 3. College of Mechanical and Electronic Engineering, Shandong {2. of science and {2., Qingdao 2.6510, P. R. China [a] Key Laboratory of Mine Hazard Prevention Control (Ministry of Education China) Shandong University of Science technology Qingdao 266510 P. R. China [b] School of Architecture Tsinghua University Beijing 100084 P. R. China [c] College of Mechanical Electronic Engineering Shandong University of Science technology Qingdao 266510 P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

Simulation study of real-time monitor for BEPC-Ⅱ luminosity

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science China(Technological sciences) 2010年第5期53卷 1215-1219页

作者： SHAN Qing1,2.WU Jian2.XUE Zhen2.XU ZiZong2.HU Tao3.WANG YiFang3.& WANG XiaoLian2.1 College of Material {2. and technology,{2. {3. of Aeronautics and Astronautics,{2. 2.0016,China 2.Department of Modern Physics,{3. of {2. and technology of China,Hefei 2.0}02.,China 3.{12. of High Energy Physics,Chinese Academy of {2.s,Beijing 100049,China College of Material science and technology Nanjing University of Aeronautics and Astronautics Nanjing China Department of Modern Physics University of Science and Technology of China Hefei China institute of High Energy Physics Chinese Academy of Sciences Beijing China

A fast and real time luminosity monitor system will be used in the BEPC-Ⅱ(Beijing Electron Positron Collider,China).Photons generated in radiative Bhabha scattering at the interaction point are transformed into charged particles,and then the luminosity of each bunch pair is measured through collecting the Cherenkov light produced by charged particles in fused *** whole process happening in the detector is *** physics acceptance and detection threshold with the monitor accu-racy of 1% are set based on the simulation spectra of photoelectron yield calibrated by e-beam data.

关键词： luminosity BEPC-Ⅱ Cherenkov detector radiative Bhabha

Trace element geochemistry of the Lower Cambrian black rock series from northwestern Hunan, South China

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Progress in Natural science:Materials International 2004年第1期14卷 65-71页

作者： PAN Jiayong 1,2. *, MA Dongsheng 1 and CAO Shuanglin 1,2. (1.The State Key Laboratory for Mineral Deposits Research, nanjing university, nanjing 2.0093. China 2. East China {3. of technology, Fuzhou 3.4000, China) nanjing Univ State Key Lab Mineral Deposit Res Nanjing 210093 Peoples R China E China Inst Technol Fuzhou 344000 Peoples R China

Samples of black rock series collected from the Lower Cambrian Niutitang Formation, northwestern Hunan Province, China, were analyzed for trace elements. The trace element geochemical characteristics of the ore layer (high enrichments of Ni, Mo, V, U, Cu, Pb, Zn, Cd, Tl and Ba; high U/Th ratios and LREE enriched patterns with positive Eu and Y anomalies) support the assumption that the Ni Mo polymetallic layer is of submarine hydrothermal origin. High field strength elements (HFSE) and lithophile elements such as Nb, Ta, Zr, Hf, Li, Be, Rb, Cs, Th and Sc are remarkably higher in the upper unit than those in the lower unit of the Niutitang Formation. These features may reflect that hydrothermal contributions were diminished, and terrigenous constituents were increased in the sediments of the upper unit of the Niutitang Formation.

关键词： black rock series Early Cambrian trace elements northwestern Hunan China