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A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

science china Earth sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2. ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3 1. International Center for Climate and Environment sciences, {2. of Atmospheric Physics, Chinese Academy of sciences, Beijing 10002., china 2. Jiangsu Key Laboratory of Meteorological Disaster, nanjing university of information science and {12., nanjing 2.0044, china 3. Beijing {2. of Applied meteorology, Beijing 10002., china 1. International Center for Climate and Environment sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing 210044 China 3. Beijing institute of Applied {{2. Beijing 100029 China

A new 3DVAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3DVAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 2.-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 42. m reach 0.63℃ and 0.34 psu.

关键词： data assimilation, 3DVAR, sea surface height, ARGO floats.

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A new parameterization scheme for sea surface aerodynamic roughness

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Progress in Natural science:Materials International 2008年第11期18卷 1365-1373页

作者： Yuping Pan~(a,b) Wenyu Sha~c Shouxian Zhu~c Sufang Ge~(a,*) a nanjing university of {{2. science and technology,nanjing 2.0044,china b Air Force Meteorological Center of the nanjing Military Region,nanjing {2.0018,china c {12. College,The PLA university of {{2. science and technology,nanjing {2.1101,china nanjing university of {{2. science and technology Nanjing 210044 China Air Force Meteorological Center of the nanjing Military Region Nanjing 210018 China meteorology College The PLA University of Information Science and Technology Nanjing 211101 China

The dimensionless roughness length derived from dimensional analysis bears a relation to wave age,and the dimensionless form of roughness length can be expressed with the relation with a significant wave *** on six experiments(HEXMAX,RASEX,BIO steady platform,Lake Ontario data analysis FETCH,CBLAST low wind),we verified that the Charnock parameter,Zch,and dimension- less roughness length,z0/Hs,are dependent on wave age,u*/***,we constructed a new scheme for roughness length,and explored its sensitivity to friction velocity and wave *** the newly developed parameterization scheme(PS07)with COARE (Coupled Ocean-Atmosphere Response Experiment V.3.0)algorithm,we calculated the data from the North Sea Platform experiment in December,1985,and made an attempt to validate the suitability of the PS07 compared to the other three schemes of *** found that the calculated results based on the PS07 are close to the *** also conducted an experiment in which the PS07 was combined with the nested model of waves coupling in datasets of 3 typhoons that occurred at the Zhanjiang *** comparison results between the calculated and observed waves around the Naozhou Island indicate that the new parameterization scheme(PS07)has a good applicability.

关键词： Sea surface roughness Parameterization scheme Significant wave height Wave age COARE algorithm

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Application of sparse S transform network with knowledge distillation in seismic attenuation delineation

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Petroleum science 2024年第4期21卷 2345-2355页

作者： Nai-Hao Liu Yu-Xin Zhang Yang Yang Rong-Chang Liu jing-Huai Gao nan Zhang School of information and Communications Engineering Xi'an Jiaotong University School of Software Engineering Xi'an Jiaotong University Petrochina Research institute of Petroleum Exploration and Development (RIPED) CNPC Research institute of Exploration and Development Yumen Oilfield Company CNPC

Time-frequency analysis is a successfully used tool for analyzing the local features of seismic ***, it suffers from several inevitable limitations, such as the restricted time-frequency resolution,the difficulty in selecting parameters, and the low computational efficiency. Inspired by deep learning,we suggest a deep learning-based workflow for seismic time-frequency analysis. The sparse S transform network(SSTNet) is first built to map the relationship between synthetic traces and sparse S transform spectra, which can be easily pre-trained by using synthetic traces and training labels. Next, we introduce knowledge distillation(KD) based transfer learning to re-train SSTNet by using a field data set without training labels, which is named the sparse S transform network with knowledge distillation(KD-SSTNet).In this way, we can effectively calculate the sparse time-frequency spectra of field data and avoid the use of field training labels. To test the availability of the suggested KD-SSTNet, we apply it to field data to estimate seismic attenuation for reservoir characterization and make detailed comparisons with the traditional time-frequency analysis methods.

关键词： S transform Deep learning Knowledge distillation Transfer learning Seismic attenuation delineation

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Distribution and Formation Causes of PM_(2.5) and O_(3) Double High Pollution Events in china during 2.13–2.

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Advances in Atmospheric sciences 2024年第6期41卷 1235-1250,I0004-I0021页

作者： Zhixuan TONG Yingying YAN Shaofei KONG Jintai LIN nan CHEN Bo ZHU jing MA Tianliang ZHAO Shihua QI Department of Atmospheric science School of Environmental SciencesChina University of GeosciencesWuhan 430074China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Research Centre for Complex Air Pollution of Hubei Province Wuhan 430074China Laboratory for Climate and Ocean–Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China Eco-Environmental Monitoring Centre of Hubei Province Wuhan 430074China Key Laboratory of Atmospheric Chemistry China Meteorological AdministrationBeijing 100081China School of Atmospheric Physics Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over china in recent years,but their causes are not completely *** this study,the spatiotemporal distribution of DHP events in china during 2.13–2. is *** synoptic types affecting DHP events are identified with the Lamb–Jenkinson circulation classification *** meteorological and chemical causes of DHP events controlled by the main synoptic types are further *** show that DHP events(1655 in total for china during 2.13–2.)mainly occur over the North china Plain,Yangtze River Delta,Pearl River Delta,Sichuan Basin,and Central *** occurrence frequency increases by 5.1%during 2.13–15,and then decreases by 56.1%during 2.15–*** main circulation types of DHP events are“cyclone”and“anticyclone”,accounting for over 40%of all DHP events over five main polluted regions in china,followed by southerly or easterly flat airflow types,like“southeast”,“southwest”,and“east”.Compared with non-DHP events,DHP events are characterized by static or weak wind,high temperature(2..9℃ versus 2..1℃)and low humidity(70.0%versus 64.9%).The diurnal cycles of meteorological conditions cause PM_(2.5)(0300–12.0 LST,Local Standard Time=UTC+8 hours)and O_(3)(1500–2.00 LST)to exceed the national standards at different periods of the DHP *** pollutant conversion indices further indicate the rapid secondary conversions during DHP events,and thus the concentrations of NO_(2.,SO_(2. and volatile organic compounds decrease by 13.1%,4.7%and 4.4%,*** results of this study can be informative for future decisions on the management of DHP events.

关键词： double high pollution events PM_(2.5) ozone spatiotemporal distribution meteorological causes chemical composition characteristics

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Application of Diagonal Recurrent Neural Network toDC Motor Speed Control Systems

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 68-71页

作者： jing Wang Hui Chen information Engineering School, {{2. of science and technology Beijing, Beijing 100083, china information Engineering School University of Science and Technology Beijing Beijine 100083 China

A new kind of dynamic neural network--diagonal recurrent neural network (DRNN) and its learning method and architecture are presented. A direct adaptive control scheme is also developed that is applied to a DC (Direct Current) speed control system with the ability to auto-tune PI (Proportion Integral) parameters based on combining DRNN with PI controller. The simulation results of DRNN show better control performances and potential practical use in comparison with PI controller.

关键词： diagonal recurrent neural network PI controller DC Motor speed control system

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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, {2. of Arid meteorology, CMA, Lanzhou 73002.,{2. 2.nanjing university of information science and technology, nanjing 2.0044,{2. 3 Zhangye National Meteorological Observatory, Zhangye 734000,{2. 4 Cold and Arid Regions Environmental and Engineering Research {2., Chinese Academy of science, Lanzhou 730000,{2. 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 China2. Nanjing University of Information Science and Technology Nanjing 210044 China3. Zhangye National Meteorological Observatory Zhangye 734000 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Science Lanzhou 730000 China

Macroscopic reason for the development of turbulences in fluid is the conjunction action of velocity and temperature shears. We use the 2.08 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

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Magnetic Properties of nanometer-Scale NiZnCu Ferrite Thin Films Fabricated by Spray-Spin-Heating-Coating Method

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Journal of Materials science & technology 2004年第1期20卷 35-37页

作者： Yulan jing, Huaiwu ZHANG, lijun JIA, Yu SHI and Yingli LIUinstitute of {{2. and Materials, university of Electronic science and technology of china, Chengdu 610054, china Inst. of Info. and Mat. Univ. of Electron. Sci. and Technol. Chengdu 610054 China

A new nanometer-scale ferrite thin film with excellent high-frequency characteristics has been developed by the spray-spin-heating-coating method. The effects of the ion synthesis mechanism, chemical stoichiometry, fabrication method, and doping content on the magnetic properties and microstructure of the thin films have been analyzed. The films formed between 75℃ and 90℃ by spray-spin-heating-coating methods was discovered with fine grain size of about 2. nm, high saturation magnetization (4πMs) of about 6.5 kGs, coercivity of about 9.8 Oe, as well as initial permeability of about 14.0. These films can be widely used in radio-frequency integrated circuit devices.

关键词： nanometer materials Ferrite thin film Spray-spin-heating-coating

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Pan-sharpening:a fast variational fusion approach

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science china({{2. sciences) 2012年第3期55卷 615-625页

作者： ZHOU ZeMing1, LI YuanXiang2., SHI HanQing1, MA Ning1 & SHEN Ji2.1{2. of meteorology, PLA {2. of science and technology, nanjing 2.1101, china 2.chool of Aeronautics and Astronautics, Shanghai JiaoTong {2., 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

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P2. traffic optimization

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science china({{2. sciences) 2012年第7期55卷 1475-1492页

作者： ZHANG GuoQiang 1,2 ,TANG MingDong 3 ,CHENG SuQi 2,4 ,ZHANG GuoQing 2 ,SONG HaiBin 5 ,CAO JiGuang 6 & YANG jing 7 1 School of Computer science and technology,nanjing Normal university,nanjing 210046,china 2 institute of Computing technology,Chinese Academy of sciences,Beijing 100190,china 3 School of Computer science and Engineering,Hunan university of science and technology,Xiangtan 411201,china 4 Graduate university of Chinese Academy of sciences,Beijing 100190,china 5 nanjing R&D Center,Huawei Technologies,nanjing 210012,china 6 china Academy of Telecommunication Research of MIIT,Beijing 100191,china 7 china Mobile Research institute,Beijing 100053,china 1. School of Computer science and technology Nanjing Normal University Nanjing 210046 China2. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China3. School of Computer Science and Engineering Hunan University of Science and Technology Xiangtan 411201 China4. Graduate University of Chinese Academy of Sciences Beijing 100190 China5. Nanjing R&D Center Huawei Technologies Nanjing 210012 China6. China Academy of Telecommunication Research of MIIT Beijing 100191 China7. China Mobile Research Institute Beijing 100053 China

Peer-to-peer (P2.) based content distribution systems have emerged as the main form for content distribution on the Internet,which can greatly reduce the distribution cost of content providers and improve the overall system ***,the mismatch between the overlay and underlay networks causes large volume of redundant traffic,which intensifies the tension between P2. content providers and ***,how to efficiently use network resources to reduce the traffic burden on the ISPs is crucial for the sustainable development of P2. *** paper surveys the state-of-art P2. traffic optimization technologies from three perspectives:P2. cache,locality-awareness and data *** details,comparison between these technologies and their applicabilities are presented,followed by a discussion of the issues that remain to be addressed and the direction of future content distribution research.

关键词： P2. traffic localization P2. traffic optimization P2. cache locality-awareness network coding content-centric network

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Geochemistry of Trace and Rare Earth Elements in Red Soils from the Dongting Lake Area and Its Environmental Significance

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Pedosphere 2009年第5期19卷 615-622页

作者： MAO Long-Jiang MO Duo-Wen YANG jing-Hong SHI Chen-Xi College of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 (China) College of Urban and Environmental sciences Peking University Beijing 100871 (China) Department of Earth sciences Nanjing University Nanjing 210093 (China)

Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of china were determined to understanding the provenance and weathering characteristics of the red *** results showed similar REE distribution patterns among red soils from the Dongting Lake area,Xiashu loess from Zhenjiang,loess and Pliocene red soil from the Loess *** patterns implied a similar provenance from dust-storms,except for red soil R5 which formed by bedrock weathering and had significant light REE(LREE) enrichment and heavy REE(HREE) depletion due to longer weathering periods and higher intensity of *** element,especially the Rb/Sr and Li/Ba ratios,and REE,especially the LREE/HREE ratio and δEu could trace weathering *** Rb/Sr,Li/Ba,and LREE/HREE ratios and negative Eu anomalies were present in the red soils from the Dongting Lake *** weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soils from the Dongting Lake area(including reticulate red soil,weak reticulate red soil,and homogeneous red soil formed by dust storms) > Xiashu loess from Zhenjiang > loess-paleosol and Pliocene red soil from the Loess *** in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity.

关键词： Hunan Province provenance sedimentary processes weathering intensity

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