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Average Widths of Sobolev-Wiener Classes with Mixed Smoothness in L_q(R^d)

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Acta Mathematica Sinica,English Series 2001年第2期17卷 305-312页

作者： He Ping WANG department of Mathematics, capital normal University. {2., 100037, P. R. china department of Mathematics Capital Normal University Beijing 100037 P. R. China

In this paper, the average σ-K width of Sobolev-Wiener classes Spqr W with mixed smooth- ness in Lq（Rd） is studied for 1d the weak asymptotical behavior of these quantities is obtained.

关键词： Sobolev-Wiener classes with mixed smoothness Average σ-K width Step hyperbolic crosses

Spatio-temporal pattern analysis of single-trial EEG signals recorded during visual object recognition

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Science china(information Sciences) 2011年第12期54卷 2519-2527页

作者： WANG ChangMing 1 , HU XiaoPing 3 , YAO Li 1,2., XIONG Shi 2.& ZHANG JiaCai 2.1 National Key laboratory of Cognitive Neuroscience and Learning, beijing {2. University, beijing 100875, china 2.College of information Science and Technology, beijing {2. University, beijing 100875, china 3 Biomedical Imaging Technology Center, Emory University/Georgia Institute of Technology, Atlanta 3032., USA 1. National Key laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China3. Biomedical Imaging Technology Center Emory University/Georgia Institute of Technology Atlanta 30322 USA2. College of Information Science and Technology Beijing Normal University Beijing 100875 China

Object discrimination is a fundamental cognitive function for human brains. In this study, we utilized an analysis approach for single-trial electroencephalography (EEG) to analyze the spatio-temporal activation patterns of visual objects processing in human brains, and attempted to apply it to discriminate different visual objects. The spatial patterns were respectively extracted from scalp EEG and the reconstructed cortical sources, while the experiment participants were perceiving 4 different categories of visual objects (faces, buildings, cats and cars). By classifying the patterns extracted from single-trial EEG, the presented visual objects could be discriminated by a computer, and the classification accuracies may provide a quantitative index to evaluate the spatial differences of the brain activations related to different visual objects. Our results demonstrated that the spatial patterns on both the scalp and the sources levels resulted in higher classification accuracies than chance rate. We also examined the classification results using temporally non-overlapping time intervals of different event-related potential (ERP) components. The temporal changes of classification accuracies may reflect the temporal distribution of the discriminative information in the EEG responses. The present pattern extraction and classification methods may compose a computational model for single-trial EEG data analysis in investigations of the spatio-temporal activation patterns for object recognition. These spatio-temporal patterns in EEG may be useful to identifying the discriminative spatial areas and time stages to improve the accuracies and efficiencies of object discrimination. In addition, investigating and utilizing humans'cognitive mechanisms of object recognition may improve computers' processing efficiency of visual information.

关键词： EEG spatio-temporal pattern object recognition single-trial analysis visual information processing

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

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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, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china 2. Jiangsu Key {2. of Meteorological disaster, Nanjing University of information Science and Technology, Nanjing 2.0044, china 3. beijing Institute 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 Meteorology 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.

An ideal interval method of multi-objective decision-making for comprehensive assessment of water resources renewability

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Science china(Technological Sciences) 2004年第z1期47卷 42-50页

作者： YANG Xiaohua1, YANG Zhifeng1,2. SHEN Zhenyao1 & LI Jianqiang3 1. School of Environment, State Key laboratory of Water Environment Simulation, beijing {2. Univer- sity, beijing 100875, china 2. School of Environment, Key laboratory for Water and Sediment Sciences of Ministry of Education, beijing {2. University, beijing 100875, china 3. Water Resources and Hydropower Planning and design General Institute, MWR, beijing 100011, china beijing normal Univ Sch Environm State Key Lab Water Environm Simulat Beijing 100875 Peoples R China beijing normal Univ Sch Environm Key Lab Water & Sediment Sci Minist Educ Beijing 100875 Peoples R China MWR Water Resources & Hydropower Planning & Design Ge Beijing 100011 Peoples R China

In order to estimate water resources renewability scientifically, an Ideal Interval Method of Multiple Objective decision-Making (IIMMOdM) is presented. This method is developed through improving an ideal point method of multiple objective decision-making. The ideal interval is obtained with assessment standard instead of ideal points. The weights are decided by using the basic point and gray code accelerating genetic algorithm. This method has synthesized the expert’s suggestion and avoided giving a mark for the objective again. It could solve the complicated problem of compatible or incompatible multi-objective assessment. The principle of IIMMOdM is presented in this paper. It is used to assess the water resources renewability for nine administrative divisions in the Yellow River basin. The result shows that the water resources renewability in the Yellow River basin is very low. Compared with the gray associate analysis method, fuzzy synthesis method and genetic projection pursuit method, the IIMMOdM is easier to use. Compared with the ideal point method of multiple objective decision-making, the IIMMOdM has good robustness, which is applicable to the comprehensive assessments of water resources.

关键词： water resources renewability, comprehensive assessment, multiple objective decision-making,ideal interval, Yellow River basin.

The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china Earth Sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2. TENG Jiwen1, Lü Qingtian3, LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 10002., china 2. Institute of Geophysics, china Seismological Bureau, beijing 100085, china 3. Institute of deposition Resource, Chinese Academy of Geosciences, beijing 100037, china 4. School of Exploration and information, china University of Geosciences, beijing 100083, china 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Institute of Geophysics China Seismological Bureau 100085 Beijing China 3. Institute of deposition Resource Chinese Academy of Geosciences 100037 Beijing China 4. School of Exploration and information China University of Geosciences 100083 Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2.km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2.segments. In the studied area, crustal thickness is about 40 km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

Wide/narrow azimuth acquisition footprints and their effects on seismic imaging

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Petroleum Science 2008年第4期5卷 308-313页

作者： di Bangrang Xu Xiucang Wei Jianxin Key laboratory of CNPC Geophysical Exploration China University of Petroleum Beijing 102249 China State Key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Key laboratory of Earth Prospecting and information Technology China University of Petroleum Beijing 102249 China

acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering. At present, the study on acquisition footprints has become a hot spot. In partnership with the dagang Oilfield, we used the channel sand body seismic physical model to study the characteristics of wide/narrow azimuth acquisition footprints and analyzed and compared the two types of footprints and their effects on target imaging. In addition, the footprints caused by data processing of the normal moveout offset （NMO） stretching aberration were discussed. These footprints are located only in the shallow or middle layer in the time slice, and possibly affect the imaging of shallow target layers, and have no influence on deep target imaging. Seismic physical modeling has its advantages in the study of acquisition footprints.

关键词： Wide/narrow azimuth geometry acquisition footprint stretching aberration time slice seismic imaging

Comparison of the influence factors on NdVI for CCd camera and WFI imager on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3, LI Xiaoying1,2.3, ZHANG Yong1,2.3, ZHAO Feng1,2.3, GU Xingfa1,3,4, ZHU Li1,2.3, WANG Pengxin5 & MIN Xiangjun6 1. State Key laboratory of Remote Sensing Science Institute of Remote Sensing application, CAS, Bei- jing 100101, {2. 2. Graduate University of Chinese Academy of Sciences, beijing 100039, {2. 3. The Center for National Spaceborne demonstration, beijing 100101, {2. 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. College of information and Electrical Engineering, {2. Agricultural University, beijing 100083, {2. 6. {2. Center for Resource Satellite data and application, beijing 100830, {2. 1. State Key laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The Center for National Spaceborne demonstration 100101 Beijing China 3. Graduate University of Chinese Academy of Sciences 100039 Beijing China 4. Institut National de la Recherche Agronomique Climat Sol Environnent 84914 Avignon France 5. College of information and Electrical Engineering China Agricultural University 100083 Beijing China 6. china Center for Resource Satellite data and application 100830 Beijing China

CCd and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NdVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCd and WFI sensors on NdVI. Results indicate that radiometric calibration is the most important factor on NdVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NdVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NdVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NdVI of WFI is higher than that of CCd. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCd WFI NdVI LAI.

Quality evaluation for air plasma spray thermal barrier coatings with pulsed thermography

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Progress in Natural Science:Materials International 2011年第4期21卷 301-306页

作者： Shi-bin ZHAO~1,Cun-lin ZHANG~2.Nai-ming WU~3,Hua-ming WANG~1 1.School of Materials Science and Engineering,Beihang University,beijing 100191,china 2.department of Physics,{2. normal University,beijing 100048,china 3.School of Jet Propulsion,Beihang University,beijing 100191,china [a] School of Materials Science and Engineering Beihang University Beijing 100191 China [b] department of Physics Capital Normal University Beijing 100048 China [c] School of Jet Propulsion Beihang University Beijing 100191 China

Pulsed thermography(PT) as a non-contact non-destructive evaluation(NdE) technique was employed to examine as-sprayed air plasma spray(APS) thermal barrier coatings(TBCs) for quality *** and micro-structural characteristics play a vital role in determining the *** this paper,PT logarithmic peak second-derivative method was adopted to measure the thickness of top *** dependent thermal images were used to characterize the microstructure which was confirmed by scanning electron microscope(SEM).The results showed that there was relationship between the temperature distribution of the surface and microstructure change in *** distribution in thermal images and measurement results of thickness were in fairly good agreement with the microstructure *** can be concluded that it was possible to employ these NdE methods as quality evaluation for as-sprayed TBCs.

关键词： thermal barrier coatings(TBCs) non-destructive evaluation(NdE) pulsed thermography microstructure thickness measurement

denitrification in Chongming east tidal flat sediment, Yangtze estuary, china

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Science china Earth Sciences 2006年第10期49卷 1090-1097页

作者： WANG dongqi1,2. CHEN Zhenlou1,3, XU Shiyuan1,2. HU Lingzhen1 & WANG Jun1,2.1. College of Resources & Environment, East china normal University, Shanghai 2.0062. china 2. State Key laboratory of Estuarine and Coastal Sediment dynamics and Morphodynamics, East china normal University, Shanghai 2.0062. china 3. Key laboratory of Geographical information Science of Ministry of Education,East china normal University,Shanghai 2.0062. china 1. College of Resources & Environment East China Normal University Shanghai 200062 China 2. State Key laboratory of Estuarine and Coastal Sediment dynamics and Morphodynamics East China Normal University Shanghai 200062 China 3. Key laboratory of Geographical information Science of Ministry of Education East China Normal University Shanghai 200062 China

From July 2.03 to July 2.04, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2.) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2. source of the water. Sediment N2. natural production rate was between -0.08 and 1.74 μmolN·m-2.h-1. N2. natural production rate was higher in the summer. The difference of the N2. natural production rate in the different tidal flats, the correlation between the N2. natural production rate and the denitrification rate, and those with the temperature and dO indicate that middle tidal flat sediment denitrification was the main process of the N2. production, while in the low tidal flat sediment, the production of the N2. came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12.to 33.34 μmolN·m-2.h-1. Temperature, dO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.