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Application of the equivalent offset migration method in acoustic log reflection imaging 被引量:6
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作者 张铁轩 陶果 +2 位作者 李君君 王兵 王华 《Applied Geophysics》 SCIE CSCD 2009年第4期303-310,393,共9页
Borehole acoustic reflection logging can provide high resolution images of nearborehole geological structure. However, the conventional seismic migration and imaging methods are not effective because the reflected wav... Borehole acoustic reflection logging can provide high resolution images of nearborehole geological structure. However, the conventional seismic migration and imaging methods are not effective because the reflected waves are interfered with the dominant borehole-guided modes and there are only eight receiving channels per shot available for stacking. In this paper, we apply an equivalent offset migration method based on wave scattering theory to process the acoustic reflection imaging log data from both numerical modeling and recorded field data. The result shows that, compared with the routine post-stack depth migration method, the equivalent offset migration method results in higher stack fold and is more effective for near-borehole structural imaging with low SNR acoustic reflection log data. 展开更多
关键词 acoustic reflection logging common scatter point gather signal processing nearborehole structure imaging
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Response of Photosynthesis, Growth, Carbon Isotope Discrimination and Osmotic Tolerance of Rice to Elevated CO_2 被引量:2
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作者 彭长连 段俊 +2 位作者 林桂珠 陈贻竹 彭少麟 《Acta Botanica Sinica》 CSCD 2002年第1期76-81,共6页
Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 conc... Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 concentration which was controlled by computer. As compared with rice at ambient 35 μmol/mol CO 2, the changes in photosynthetic rate at elevated CO 2 showed up_regulation ('IR72' and 'Tesanai 2'), stable (unchanged) in 'Guichao 2' and down_regulation type ('IIyou 4480'). Growth rate, panicle weight, integrated water use efficiency (WUE) calculated from Δ 13 C and the capacity of scavenging DPPH · (1,1_diphenyl_2_picrylhydrazyl) free radical were increased at elevated CO 2. An increment in total biomass was observed in three cultivars by elevated CO 2, with the exception of 'IIyou 4480'. Ratios of panicle weight/total biomass were altered to different extents in tested cultivars by elevated CO 2. When leaf segments were subjected to PEG osmotic stress, the electrolyte leakage rate from leaves grown at elevated CO 2 was less than that at 35 μmol/mol CO 2. Those intraspecific variations of rice imply a possibility for selecting cultivars with maximal productivity and high tolerance to stresses adapted to elevated CO 2 in the future. 展开更多
关键词 rice cultivars elevated CO 2 PHOTOSYNTHESIS water use efficiency 13 C discrimination osmotic tolerance
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Error Analysis on Gradient Information of Sloping Land Derived from the Low-resolution DEM 被引量:6
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作者 王莉 贺秀斌 +2 位作者 鲍玉海 南宏伟 刘艳锋 《Agricultural Science & Technology》 CAS 2010年第1期109-112,共4页
With digital elevation model (DEM),sloping data were extracted automatically and soil erosion situation was also investigated. Compared with field survey and the related studies,the results showed that parallel rang... With digital elevation model (DEM),sloping data were extracted automatically and soil erosion situation was also investigated. Compared with field survey and the related studies,the results showed that parallel range-gorge landform in Three Gorges reservoir area,the inter-bedded structures formed by Jurassic purple clay (page) rocks and human activities were the key controlling factors for small-scale sloping terrain. 展开更多
关键词 Sloping land Resolution of DEM Land use Soil erosion
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家用扫描仪选购指南(下)
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作者 吴光浩 《电脑采购》 2000年第41期8-8,共1页
精挑细选定好要选的产品就该挑选需要的扫描仪,那怎样才能按以上标准,做到不受骗,又能买到一台好的扫描仪呢? 首先看扫描仪的外观,一台外观漂亮的扫描仪,能为家庭增色不少。并且还要看是否坚固,因为扫描仪的外壳同样是一个非常重要的部... 精挑细选定好要选的产品就该挑选需要的扫描仪,那怎样才能按以上标准,做到不受骗,又能买到一台好的扫描仪呢? 首先看扫描仪的外观,一台外观漂亮的扫描仪,能为家庭增色不少。并且还要看是否坚固,因为扫描仪的外壳同样是一个非常重要的部件,这是因为扫描仪内所有的运动部件都固定在扫描仪的外壳上,壳体的强度和刚度对扫描仪的清晰度影响非常大,设计良好的外壳您只要打开扫描仪的上盖,就可以在扫描仪的内壁上看到一条条明显的加强肋,而且扫描仪的底板也不是平整的,有很多凹凸。而差的外壳则只有一层薄薄的塑料壳,它的强度很低。大家也不要迷信金属外壳,这个价位扫描仪的金属外壳只是一层薄薄的铁皮,使用时间一长,就会出现变形,使扫描精度下降。第二看扫描仪的驱动程序,必须要有明显的色彩校正选项。 展开更多
关键词 家用扫描仪 驱动程序 用辨率
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Ocean mesoscale structure–induced air–sea interaction in a high-resolution coupled model 被引量:5
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作者 LIN Pengfei LIU Hailong +1 位作者 MA Jing LI Yiwen 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第2期98-106,共9页
Using the Community Earth System Model framework, the authors build a very-high-resolution quasi-global coupled model by coupling an eddy-resolving quasi-global ocean model with a high-resolution atmospheric model. Th... Using the Community Earth System Model framework, the authors build a very-high-resolution quasi-global coupled model by coupling an eddy-resolving quasi-global ocean model with a high-resolution atmospheric model. The model is successfully run for six years under present climate conditions, and the simulations are evaluated against observational and reanalysis data.The model is capable of simulating large-scale oceanic and atmospheric circulation patterns, sea surface temperature(SST) fronts, oceanic eddy kinetic energy, and fine-scale structures of surface winds. The ocean mesoscale structure–induced air–sea interaction characteristics are explored in detail. The model can effectively reproduce positive correlations between SST and surface wind stress induced by mesoscale structures through comparison with observations. The positive correlation is particularly significant over regions with strong oceanic fronts and eddies.However, the responses of wind stress to eddy-induced SST are weaker in the simulation than in the observations, although different magnitudes exist in different areas. Associated with weak wind responses, surface sensible heat flux responses to eddy-induced SST are underestimated slightly, while surface latent heat flux responses are overestimated because of the drier atmospheric boundary layers in the model. Both momentum mixing and pressure adjustment mechanisms play important roles in surface wind changes over oceanic fronts and eddies in the high-resolution model. 展开更多
关键词 Air–sea interaction oceanic front EDDY high-resolution simulation
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On the initiation,movement and deposition of a large landslide in Maoxian County,China 被引量:4
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作者 pei xiang-jun guo bin +3 位作者 cui sheng-hua wang dong-po xu qiang li tian-tao 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1319-1330,共12页
At 5 am 24 th June 2017, a catastrophic landslide hit Xinmo Village, Maoxian County, Sichuan Province, China. The slide mass rushed down from an altitude of 3400 m and traveled 2700 m in a high velocity. The 13 millio... At 5 am 24 th June 2017, a catastrophic landslide hit Xinmo Village, Maoxian County, Sichuan Province, China. The slide mass rushed down from an altitude of 3400 m and traveled 2700 m in a high velocity. The 13 million m^3 deposition buried the whole village and caused about 100 deaths. The source area of the landslide is located in a high steep slope, average slope angle is 40o and maximal angle is 65o. The strata are interbedded Triassic Zagunao Formation metamorphic sandstone and slate with the dip slope angle of 45°. Based on high-resolution satellite remote sensing image, UAV image, DEM data, and field investigation, failure mechanism, travel features, and deposit characteristics were analyzed. The results showed that this landslide was influenced by Songpinggou Fault zone. According to the topography before the failure, the landslide is located in the back scarp of an antecedent landslide induced by Diexi Earthquake in 1933. The bedding slope provided potential rupture surface. Historical seismic activities and long-term gravitational deformation caused rock mass accumulated damages. Weathering and precipitation weakened the rock mass and finally induced shearing and tension failure. A huge block detached from the top rock slope, pushed the past landslide deposits in the middle part, rushed out of the slope bottom in a high velocity and buried the Xinmo Village. The rapid movement entrained and brought the soil into the Songping Gully which recoiled with and bounced back from the opposite mountain. 展开更多
关键词 Xinmo landslide Seismic damages Longrunout Failure mechanism Rock fragment
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Joint User Scheduling and Antenna Selection in Distributed Massive MIMO Systems with Limited Backhaul Capacity 被引量:9
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作者 XU Guozhen LIU An +2 位作者 JIANG Wei XIANG Haige LUO Wu 《China Communications》 SCIE CSCD 2014年第5期17-30,共14页
Massive MIMO systems offer a high spatial resolution that can drastically increase the spectral and/or energy efficiency by employing a large number of antennas at the base station(BS).In a distributed massive MIMO sy... Massive MIMO systems offer a high spatial resolution that can drastically increase the spectral and/or energy efficiency by employing a large number of antennas at the base station(BS).In a distributed massive MIMO system,the capacity of fiber backhaul that links base station and remote radio heads is usually limited,which becomes a bottleneck for realizing the potential performance gain of both downlink and uplink.To solve this problem,we propose a joint antenna selection and user scheduling which is able to achieve a large portion of the potential gain provided by the massive MIMO array with only limited backhaul capacity.Three sub-optimal iterative algorithms with the objective of sumrate maximization are proposed for the joint optimization of antenna selection and user scheduling,either based on greedy fashion or Frobenius-norm criteria.Convergence and complexity analysis are presented for the algorithms.The provided Monte Carlo simulations show that,one of our algorithms achieves a good tradeoff between complexity and performance and thus is especially fit for massive MIMO systems. 展开更多
关键词 massive MIMO limited backhaul capacity antenna selection user scheduling
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Improving wavelet reconstruction algorithm to achieve comprehensive application of thermal infrared remote sensing data from TM and MODIS 被引量:1
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作者 周启刚 Chen Dan 《High Technology Letters》 EI CAS 2015年第2期224-230,共7页
According to the data characteristics of Landsat thematic mapper (TM) and MODIS, a new fu sion algorithm about thermal infrared data has been proposed in the article based on improving wave let reconstruction. Under... According to the data characteristics of Landsat thematic mapper (TM) and MODIS, a new fu sion algorithm about thermal infrared data has been proposed in the article based on improving wave let reconstruction. Under the domain of neighborhood wavelet reconstruction, data of TM and MO DIS are divided into three layers using wavelet decomposition. The texture information of TM data is retained by fusing highfrequency information. The neighborhood correction coefficient method (NC CM) is set up based on the search neighborhood of a certain size to fuse lowfrequency information. Thermal infrared value of MODIS data is reduced to the space value of TM data by applying NCCM. The data with high spectrum, high spatial and high temporal resolution, are obtained through the al gorithm in the paper. Verification results show that the texture information of TM data and high spec tral information of MODIS data could be preserved well by the fusion algorithm. This article could provide technical support for high precision and fast extraction of the surface environment parame ters. 展开更多
关键词 neighborhood wavelet reconstruction neighborhood correction coefficient method( NCCM) thematic mapper (TM) MODIS thermal infrared remote sensing image
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LAND-COVER DENSITY-BASED APPROACH TO URBAN LAND USE MAPPING USING HIGH-RESOLUTION IMAGERY 被引量:1
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作者 ZHANGXiu-ying FENGXue-zhi 《Chinese Geographical Science》 SCIE CSCD 2005年第2期162-167,共6页
Nowadays, remote sensing imagery, especially with its high spatialresolution, has become an indispensable tool to provide timely up-gradation of urban land use andland cover information, which is a prerequisite for pr... Nowadays, remote sensing imagery, especially with its high spatialresolution, has become an indispensable tool to provide timely up-gradation of urban land use andland cover information, which is a prerequisite for proper urban planning and management. Thepossible method described in the present paper to obtain urban land use types is based on theprinciple that land use can be derived from the land cover existing in a neighborhood. Here, movingwindow is used to represent the spatial pattern of land cover within a neighborhood and seven windowsizes (61mx61m, 68mx68m, 75mx75m, 87mx87m, 99mx99m, 110mx110m and 121mxl21m) are applied todetermining the most proper window size. Then, the unsupervised method of ISODATA is employed toclassify the layered land cover density maps obtained by the moving window. The results of accuracyevaluation show that the window size of 99mx99m is proper to infer urban land use categories and theproposed method has produced a land use map with a total accuracy of 85%. 展开更多
关键词 urban land use land cover density map high-resolution image
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Fingerprint Liveness Detection Based on Multi-Scale LPQ and PCA 被引量:13
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作者 Chengsheng Yuan Xingming Sun Rui Lv 《China Communications》 SCIE CSCD 2016年第7期60-65,共6页
Fingerprint authentication system is used to verify users' identification according to the characteristics of their fingerprints.However,this system has some security and privacy problems.For example,some artifici... Fingerprint authentication system is used to verify users' identification according to the characteristics of their fingerprints.However,this system has some security and privacy problems.For example,some artificial fingerprints can trick the fingerprint authentication system and access information using real users' identification.Therefore,a fingerprint liveness detection algorithm needs to be designed to prevent illegal users from accessing privacy information.In this paper,a new software-based liveness detection approach using multi-scale local phase quantity(LPQ) and principal component analysis(PCA) is proposed.The feature vectors of a fingerprint are constructed through multi-scale LPQ.PCA technology is also introduced to reduce the dimensionality of the feature vectors and gain more effective features.Finally,a training model is gained using support vector machine classifier,and the liveness of a fingerprint is detected on the basis of the training model.Experimental results demonstrate that our proposed method can detect the liveness of users' fingerprints and achieve high recognition accuracy.This study also confirms that multi-resolution analysis is a useful method for texture feature extraction during fingerprint liveness detection. 展开更多
关键词 fingerprint liveness detection wavelet transform local phase quantity principal component analysis support vector machine
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Application of MODIS data in monitoring suspended sediment of Taihu Lake,China 被引量:2
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作者 蒋兴伟 唐军武 +2 位作者 张民伟 马荣华 丁静 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期614-620,共7页
Application of MODIS in ocean color is mainly based on bands 8-16 with the spatial resolution of 1 000 m.This spatial resolution,however,can not meet the application demand of inland waters where the areas are relativ... Application of MODIS in ocean color is mainly based on bands 8-16 with the spatial resolution of 1 000 m.This spatial resolution,however,can not meet the application demand of inland waters where the areas are relatively small.With the assumption of the black water at shortwave infrared(SWIR) wavelengths(>1 000 nm),we first propose an atmospheric correction method for bands 1 and 2 with their spatial resolution of 250 m,and we then establish a quantitative retrieval model for suspended sediment concentration retrieval using the in-situ data collected in Taihu Lake.We also use MODIS data to retrieve the suspended sediment concentration of Taihu Lake with the retrieval model.The comparison between the retrieved and measured suspended sediment concentrations confirms that our algorithm can provide reliable data for monitoring the suspended sediment in Taihu Lake. 展开更多
关键词 Suspended sediment concentration MODIS atmospheric correction Taihu Lake
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A Confocal Endoscope for Cellular Imaging 被引量:11
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作者 Jiafu Wang Min Yang +5 位作者 Li Yang Yun Zhang Jing Yuan Qian Liu Xiaohua Hou Ling Fu 《Engineering》 SCIE EI 2015年第3期351-360,共10页
Since its inception, endoscopy has aimed to establish an immediate diagnosis that is virtually consistent with a histologic diagnosis. In the past decade, confocal laser scanning microscopy has been brought into endos... Since its inception, endoscopy has aimed to establish an immediate diagnosis that is virtually consistent with a histologic diagnosis. In the past decade, confocal laser scanning microscopy has been brought into endoscopy, thus enabling in vivo microscopic tissue visualization with a magnification and resolution comparable to that obtained with the ex vivo microscopy of histological specimens. The major challenge in the development of instrumentation lies in the miniaturization of a fiber-optic probe for microscopic imaging with micron-scale resolution. Here, we present the design and construction of a confocal endoscope based on a fiber bundle with 1.4-μm lateral resolution and 8-frames per second(fps) imaging speed. The fiber-optic probe has a diameter of 2.6 mm that is compatible with the biopsy channel of a conventional endoscope. The prototype of a confocal endoscope has been used to observe epithelial cells of the gastrointestinal tracts of mice and will be further demonstrated in clinical trials. In addition, the confocal endoscope can be used for translational studies of epithelial function in order to monitor how molecules work and how cells interact in their natural environment. 展开更多
关键词 cellular resolution confocal endoscopy optical biopsy
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Identifying Sky Conditions in Iran from MODIS Terra and Aqua Cloud Products
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作者 khodakaram hatami bahmanbeiglou saeed movahedi 《Chinese Geographical Science》 SCIE CSCD 2017年第5期800-809,共10页
Clouds can influence climate through many complex interactions within the hydrological cycle. Due to the important effects of cloud cover on climate, it is essential to study its variability over certain geographical ... Clouds can influence climate through many complex interactions within the hydrological cycle. Due to the important effects of cloud cover on climate, it is essential to study its variability over certain geographical areas. This study provides a spatial and temporal distribution of sky conditions, cloudy, partly cloudy, and clear days, in Iran. Cloud fraction parameters were calculated based on the cloud product (collection 6_L2) obtained from the Moderate Resolution Imaging Spectroradiorneter (MODIS) sensors on board the Terra (MOD06) and Aqua (MYD06) satellites. The cloud products were collected daily from January 1, 2003 to December 31, 2014 (12 years) with a spatial resolution of 5 km × 5 km. First, the cloud fraction data were converted into a regular geographic coordinate network over Iran. Then, the estimations from both sensors were analyzed. Results revealed that the maximum annual frequency of cloudy days occurs along the southern shores of the Caspian Sea, while the minimum annual frequency occurs in southeast Iran. On average, the annual number of cloudy and clear-sky days was 88 and 256 d from MODIS Terra, as compared to 96 and 244 d from MODIS Aqua. Generally, cloudy and partly cloudy days decrease from north to south, and MODIS Aqua overestimates the cloudy and partly cloudy days compared to MODIS Terra. 展开更多
关键词 cloud fraction sky conditions Moderate Resolution Imaging Spectroradiometer (MODIS) Terra satellite Aqua satellite Iran
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High Resolution Land Cover Datasets Integration and Application Based on Landsat and GlobCover Data from 1975 to 2010 in Siberia
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作者 LIU Tingxiang ZHANG Shuwen +3 位作者 XU Xinliang BU Kun NING Jia CHANG Liping 《Chinese Geographical Science》 SCIE CSCD 2016年第4期429-438,共10页
Land cover is recognized as one of the fundamental terrestrial datasets required in land system change and other ecosystem related researches across the globe. The regional differentiation and spatial-temporal variati... Land cover is recognized as one of the fundamental terrestrial datasets required in land system change and other ecosystem related researches across the globe. The regional differentiation and spatial-temporal variation of land cover has significant impact on regional natural environment and socio-economic sustainable development. Under this context, we reconstructed the history land cover data in Siberia to provide a comparable datasets to the land cover datasets in China and abroad. In this paper, the European Space Agency(ESA) Global Land Cover Map(GlobCover), Landsat Thematic Mapper(TM), Enhanced Thematic Mapper(ETM), Multispectral Scanner(MSS) images, Google Earth images and other additional data were used to produce the land cover datasets in 1975 and 2010 in Siberia. Data evaluation show that the total user′s accuracy of land cover data in 2010 was 86.96%, which was higher than ESA GlobCover data in Siberia. The analysis on the land cover changes found that there were no big land cover changes in Siberia from 1975 to 2010 with only a few conversions between different natural forest types. The mainly changes are the conversion from deciduous needleleaf forest to deciduous broadleaf forest, deciduous needleleaf forest to mixed forest, savannas to deciduous needleleaf forest etc., indicating that the dominant driving factor of land cover changes in Siberia was natural element rather than human activities at some extent, which was very different from China. However, our purpose was not just to produce the land cover datasets at two time period or explore the driving factors of land cover changes in Siberia, we also paid attention on the significance and application of the datasets in various fields such as global climate change, geopolitics, cross-border cooperation and so on. 展开更多
关键词 land cover change LANDSAT data integration data application Siberia
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Non-classical Algorithm for Time Series Prediction of the Range of Economic Phenomena With Regard to the Interaction of Financial Market Indicators 被引量:2
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作者 Monika Hadas-Dyduch 《Chinese Business Review》 2014年第4期221-231,共11页
The aim of the article is to present non-clasical copyrighted algorithm for prediction of time series, presenting macroeconomic indicators and stock market indices. The algorithm is based on artificial neural networks... The aim of the article is to present non-clasical copyrighted algorithm for prediction of time series, presenting macroeconomic indicators and stock market indices. The algorithm is based on artificial neural networks and multi-resolution analysis (the algorithm is based on Daubechies wavelet). However, the main feature of the algorithm, which gives a good quality of the forecasts, is all included in the series analysis division into, a few partial under-series and prediction dependence on a number of other economic series. The algorithm used for the prediction, is copyrighted algorithm, labeled M.H-D in this article. Application of the algorithm was performed on a series presenting WIG 20. The forecast of WIG 20 was conditional on trading the Dow Jones, DAX, Nikkei, Hang Seng, taking into account the sliding time window. As an example application of copyrighted model, the forecast of WIG 20 for a period of two years, one year, six month was appointed. An empirical example is described. It shows that the proposed model can predict index with the scale of two years, one year, a half year and other intervals. Precision of prediction is satisfactory. An average absolute percentage error of each forecast was: 0.0099%---for two-year forecasts WIG 20; 0.0552%--for the annual forecast WIG 20; and 0.1788%---for the six-month forecasts WIG 20. 展开更多
关键词 macroeconomic indicators stock index forecasting WAVELET neural network wavelet transform Daubechies wavelet
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Satellite derived upper ocean thermal structure and its application to tropical cyclone intensity forecasting in the Indian Ocean 被引量:1
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作者 孙春健 王喜冬 +6 位作者 崔晓健 张晓爽 张连新 邵彩霞 吴新荣 付红丽 李威 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第5期1219-1232,共14页
Upper ocean heat content is a factor critical to the intensity change of tropical cyclones(TCs). Because of the inhomogeneity of in situ observations in the North Indian Ocean,gridded temperature/salinity(T/S) profile... Upper ocean heat content is a factor critical to the intensity change of tropical cyclones(TCs). Because of the inhomogeneity of in situ observations in the North Indian Ocean,gridded temperature/salinity(T/S) profiles were derived from satellite data for 1993–2012 using a linear regression method. The satellite derived T/S dataset covered the region of 10°S–32°N,25°–100°E with daily temporal resolution,0.25°×0.25° spatial resolution,and 26 vertical layers from the sea surface to a depth of 1 000 m at standard layers. Independent Global Temperature Salinity Profile Project data were used to validate the satellite derived T/S fields. The analysis confirmed that the satellite derived temperature field represented the characteristics and vertical structure of the temperature field well. The results demonstrated that the vertically averaged root mean square error of the temperature was 0.83 in the upper 1 000 m and the corresponding correlation coefficient was 0.87,which accounted for 76% of the observed variance. After verification of the satellite derived T/S dataset,the TC heat potential(TCHP) was verified. The results show that the satellite derived values were coherent with observed TCHP data with a correlation coefficient of 0.86 and statistical significance at the 99% confidence level. The intensity change of TC Gonu during a period of rapid intensification was studied using satellite derived TCHP data. A delayed effect of the TCHP was found in relation to the intensity change of Gonu,suggesting a lag feature in the response of the inner core of the TC to the ocean. 展开更多
关键词 tropical cyclone intensification tropical cyclone heat potential sea surface temperature seasurface height
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Spatial Structure and Land Use Control in Extended Metropolitan Region of Zhujiang River Delta,China 被引量:4
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作者 DAI Junliang WANG Kaiyong GAO Xiaolu 《Chinese Geographical Science》 SCIE CSCD 2010年第4期298-308,共11页
The Zhujiang (Pearl) River Delta is one of the most developed Extended Metropolitan Regions (EMR) in China.With the rapid urbanization,the agglomeration of population and industries has emerged,which has led to dramat... The Zhujiang (Pearl) River Delta is one of the most developed Extended Metropolitan Regions (EMR) in China.With the rapid urbanization,the agglomeration of population and industries has emerged,which has led to dramatic changes of spatial structure and land use in this region.With data of high resolution TM remote sensing images and Google Earth maps,this paper identified and analyzed the spatial pattern of the Zhujiang River Delta EMR using Envy and ArcGIS tools.It was found that 1) the industrial land uses were expanding substantially,particularly on the bank sides of the Zhujiang River estuary;2) large-scale housing developments were concentrated in the fringe of metropolitan areas such as those of Guangzhou and Shenzhen;3) a regional transportation network with the spatial pattern of ″1 circle +2 pieces + 3 axes″ had significantly affected the location choice of manufacture enterprises.At the same time,both highly specialized land use and severely mixed land use patterns were identified.As a consequence of the latter,land use efficiency of the whole EMR areas was reduced.Moreover,ecologic and environmental problems were severe.Based on the above analysis,suggestions were given from the viewpoint of spatial safety,land use efficiency,and the reorganization of spatial structure in the Zhujiang River Delta EMR. 展开更多
关键词 spatial pattern agglomeration and expansion spatial expansion Extended Metropolitan Region (EMR) Zhujiang River Delta (Pearl River Delta)
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Interaction between Topographic Conditions and Entrainment Rate in Numerical Simulations of Debris Flow
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作者 Norifumi HOTTA Haruka TSUNETAKA Takuro SUZUKI 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1383-1394,共12页
Debris flow simulations are useful for predicting the sediment supplied to watersheds from upstream areas. However, the topographic conditions upstream are more complicated than those downstream and the relationship b... Debris flow simulations are useful for predicting the sediment supplied to watersheds from upstream areas. However, the topographic conditions upstream are more complicated than those downstream and the relationship between the topographic conditions and debris flow initiation is not well understood. This study compared the use of several entrainment rate equations in numerical simulations of debris flows to examine the effect of topographic conditions on the flow. One-dimensional numerical simulations were performed based on the shallow water equations and three entrainment rate equations were tested. These entrainment rate equations were based on the same idea that erosion and the deposition of debris flows occur via the difference between the equilibrium and current conditions of debris flows, while they differed in the expression of the concentration, channel angle, and sediment amount. The comparison was performed using a straight channel with various channel angles and a channel with a periodically undulating surface. The three entrainment rate equations gave different amounts of channel bed degradation and hydrographs for a straight channel with a channel angle greater than 21° when water was supplied from upstream at a steady rate. The difference was caused by the expression of the entrainment rate equations. For channels with little undulation, the numerical simulations gave results almost identical to those for straight channels with the same channel angle. However, for channels with large undulations, the hydrographs differed from those for straight channels with the same channel angle when the channel angle was less than 21°. Rapid erosion occurred and the hydrograph showed a significant peak, especially in cases using the entrainment equation expressed by channel angle. This was caused by the effects of the steep undulating sections, since the effect increased with the magnitude of the undulation, suggesting that a debris flow in an upstream area develops differently according to the topographic conditions. These results also inferred that numerical simulations of debris flow can differ depending on the spatial resolution of the simulation domain, as the resolution determines the reproducibility of the undulations. 展开更多
关键词 Debris flow Entrainment rate equation Numerical simulation Topographic condition
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Application of ultrasound in the diagnosis of clinical anesthesia
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作者 Zhongqun Wang 《International Journal of Technology Management》 2013年第9期64-66,共3页
During the past 10 years, the rapid development of ultrasound technology in clinical anesthesia has become one of the hot clinical researches. Researches in this area home and abroad also made great progress. On the o... During the past 10 years, the rapid development of ultrasound technology in clinical anesthesia has become one of the hot clinical researches. Researches in this area home and abroad also made great progress. On the one hand due to improved high-resolution portable ultrasound instrument and probe technology, ultrasound changed from a purely clinical diagnostic into the operating room; on the other hand, with the traditional method of anesthesia increasingly unable to meet the clinical requirements, it is an objective need of technological innovation for clinical anesthesia. And ultrasound has non-invasive, real-time, visible and repeatable characteristics which are able to provide accurate data and rich means for preoperative assessment, intraoperative monitoring and treatment of pain in pre-clinical anesthesia 展开更多
关键词 ULTRASOUND clinical anesthesia DIAGNOSTIC
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Application of Remote Sensing and Geographic Information System to Elaborate UQI (Urban Quality Index): A Case of Casablanca, Morocco
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作者 Aziza Berrada Hassan Rhinan Atika Hilali Youssef Bedraoui 《Journal of Environmental Science and Engineering(B)》 2013年第7期406-415,共10页
The urban environmental quality remains currently difficult to be assessed because of overlapping of several natural and anthropogenic factors having socio-economic and environmental outstanding impacts. The fast deve... The urban environmental quality remains currently difficult to be assessed because of overlapping of several natural and anthropogenic factors having socio-economic and environmental outstanding impacts. The fast developing and uncontrolled urbanization is behind the development of some negative side effects on the urban environment. Many studies demonstrate the ability of remote sensing and GIS (geographic information system) to monitor urban environment quality. Casablanca, Morocco's economical capital is facing a fast growing demographic development amplified by a massive rural depopulation and all this in an anarchic way. This growth of increased urban activity comes often with the proliferation of informal settlement and shantytown to the detriment of farming areas and green spaces. This study is made possible by using a SPOT-5 image of Casablanca city, taken March 16, 2004 merged with 2.5 m spatial resolution and census data. Indicators were defined and listed in social, economic and environmental categories. An index of environmental quality in Casablanca city for the 17 urban municipalities was calculated after the standardization and weighting of indicators used. The results may be useful to city managers and planners who are concerned with urban environment quality issues and sustainable development. 展开更多
关键词 UQI (urban quality index) INDICATORS remote sensing census data METADATA ArcGIS.
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