To support amplitude variation with offset (AVO) analysis in complex structure areas, we introduce an amplitude-preserving plane-wave prestack time migration approach based on the double-square-root wave equation in...To support amplitude variation with offset (AVO) analysis in complex structure areas, we introduce an amplitude-preserving plane-wave prestack time migration approach based on the double-square-root wave equation in media with little lateral velocity variation. In its implementation, a data mapping algorithm is used to obtain offset-plane-wave data sets from the common-midpoint gathers followed by a non-recursive phase-shift solution with amplitude correction to generate common-image gathers in offset-ray-parameter domain and a structural image. Theoretical model tests and a real data example show that our prestack time migration approach is helpful for AVO analysis in complex geological environments.展开更多
Texture acquisition of a large scale scene is one of the critical research areas in computer vision and can be used in other application areas such as computer graphics (CG), the intelligent transportation system (ITS...Texture acquisition of a large scale scene is one of the critical research areas in computer vision and can be used in other application areas such as computer graphics (CG), the intelligent transportation system (ITS) and the 3D geographic information system (GIS). Moreover, to acquire texture without noise (e.g., a shadow, an obstacle body) is vital for such work. Although obstacles can be removed by using 3D geometric data, shadow elimination is still a difficult problem and strongly required for the CG and ITS community, especially for city modeling and simulation purposes. In this paper, we propose an automatic multiple image fusion technique and an efficient and simple shadow removing technique to retrieve high quality texture images of an urban area. The image fusion can be efficiently achieved by epipolar plane image (EPI) analysis, and the shadow elimination can be successfully carried out by an illumination independent color clustering technique. The strength of this algorithm is that we can successfully fuse multiple images and eliminate shadows from the fused single image, especially in low dynamic range images, which have proven difficult using previous techniques.展开更多
A surface equation of state, applicable to liquid-expanded (LE) monolayers, was derived by analyzing the Helmholtz free energy of the LE monolayers. Based on this equation, a general equation was obtained to describe ...A surface equation of state, applicable to liquid-expanded (LE) monolayers, was derived by analyzing the Helmholtz free energy of the LE monolayers. Based on this equation, a general equation was obtained to describe all states of single-component phospholipid monolayers during comprassion. To verify the applicability of the equation, π-A isotherms of 1,2-dipalmitoylphosphatidylcholine (DPPC), 1,2-dipalmitoylphosphatidylglycerol (DPPG), and 1,2-dimyristoyphosphatildylcholine (DMPC) were measured. The comparison between model and experimental values indicates that the equation can describe the behavior of pure phospholipid monolayers.展开更多
A modular flat-screen liquid crystal television display is described. The picture elements of the modules may be emissive, reflective or transmissive. The flat-screen liquid crystal television also comprised of an ele...A modular flat-screen liquid crystal television display is described. The picture elements of the modules may be emissive, reflective or transmissive. The flat-screen liquid crystal television also comprised of an electrical control circuit capable of categorizing incoming television picture signals corresponding to the modules in the array and directing the electrical signals to the drive circuits of each module according to the portion of the television picture to be reproduced by the picture elements of that module. The picture elements are preferably formed in a light modulating film composed of a liquid crystal dispersion in a polymeric binder. A color display was also produced by placing a patterned red-green-blue filter adjacent the active matrix so that each picture element could also be coordinated with the color components of a color video signal.展开更多
This paper analyzes the key technology of mobile GIS development, discusses the design method of mobile GIS spatial data management, visualization of spatial data And Spatial data query, tinder Object oriented mode. A...This paper analyzes the key technology of mobile GIS development, discusses the design method of mobile GIS spatial data management, visualization of spatial data And Spatial data query, tinder Object oriented mode. And we develop a set of mobile GIS basic software platform in the Android platform, and tested in the mainstream smart mobile phone with Android operating system, test results show that the software platform can run smoothly. Other users can development a variety of mobile GIS to call the platform through an application service interface.展开更多
The vulnerability of Egypt to potential impacts of sea level rise has been considered. It was recognized that many locations in Egyptian Coast, on Mediterranean Sea (Mersa Matruh, Alexandria and Port Said) and on Re...The vulnerability of Egypt to potential impacts of sea level rise has been considered. It was recognized that many locations in Egyptian Coast, on Mediterranean Sea (Mersa Matruh, Alexandria and Port Said) and on Red Sea (Hurghada), are highly vulnerable to the potential impacts of sea level rise, salt water intrusion and increase of frequency and severity of storm surges. The aim of this study is to investigate the monthly average and the variations of sea level and meteorological conditions along the Egyptian Mediterranean and north Red Sea coasts. Monthly mean cycles and correlation coefficients between MSL (Mean Sea Level) and different meteorological parameters were also calculated. The analyzed data was from 2007 to 2009 covering 3 years of hourly recorded sea level and meteorological parameters were used except for Hurghada sea level was for 2007 and 2008. Sea level harmonic analyses were done by using TOGA (Tropical Ocean and Global Atmosphere) software. Sea level variations were also computed, and it was 20.1,20, 0.1 and 55.3 cm in Alexandria, Port Said, Mersa Matruh and Hurghada respectively. The annual of the tidal constituents were computed to determine the MSL. Surge calculations were done by using TOGA software and eliminating the predicted tide from the observed sea level. The average calculated surge was also analyzed that the highest surge happened during summer and the lowest during winter in Alexandria and Port Said, while the highest surge was during winter and the lowest during summer in Hurghada. The surge variation was very weak in Mersa Matruh. The result of multiple regression analysis is a statistically significant relationship between the variables at the 99% confidence level.展开更多
Based on global solar radiation and related meteorological data from 57 stations in China between 1961 and 2009, we analyze the variation of surface global solar radiation (G) and its relationship to meteorological el...Based on global solar radiation and related meteorological data from 57 stations in China between 1961 and 2009, we analyze the variation of surface global solar radiation (G) and its relationship to meteorological elements using linear-trend estimation, wavelet analysis, and the Mann-Kendall test. The results show that of the 33 stations with time series longer than 45 years, G is significant at the 95% confidence level. G has a decreasing trend at many stations, but results vary across different areas. The decadal departure percentage of G increased from the 1960s to 1970s, declined gradually after the 1970s, and decreased significantly in the 1980s. In the 1990s, the trend at a few sites slightly increased. The trend of cumulative variance is of four types, i.e. rise-fall, rise-fall-slight rise, rise-fall-rise, and not obvious. For changes within a year, the most obvious decline was in winter, and the rest of the year had a slight decrease. The major cycles of annual G were 6-9, 10-13, and 29-33 a. The inflection points were mostly in the 1970s. The reasons for greater changes were complex. Relevant meteorological elements were selected and analyzed by statistical methods. Trends in climatic parameters, such as annual average percentage of sunshine, annual average wind speed, and annual average of low cloud cover, were closely related to G. Thus, this indicated the potential causes of the observed trends in G. The long-term trend for annual G in some regions was also influenced by anthro- pogenic activities. Annual average percentage of sunshine and annual average wind speed were positively correlated with annual G, respectively.展开更多
文摘To support amplitude variation with offset (AVO) analysis in complex structure areas, we introduce an amplitude-preserving plane-wave prestack time migration approach based on the double-square-root wave equation in media with little lateral velocity variation. In its implementation, a data mapping algorithm is used to obtain offset-plane-wave data sets from the common-midpoint gathers followed by a non-recursive phase-shift solution with amplitude correction to generate common-image gathers in offset-ray-parameter domain and a structural image. Theoretical model tests and a real data example show that our prestack time migration approach is helpful for AVO analysis in complex geological environments.
文摘Texture acquisition of a large scale scene is one of the critical research areas in computer vision and can be used in other application areas such as computer graphics (CG), the intelligent transportation system (ITS) and the 3D geographic information system (GIS). Moreover, to acquire texture without noise (e.g., a shadow, an obstacle body) is vital for such work. Although obstacles can be removed by using 3D geometric data, shadow elimination is still a difficult problem and strongly required for the CG and ITS community, especially for city modeling and simulation purposes. In this paper, we propose an automatic multiple image fusion technique and an efficient and simple shadow removing technique to retrieve high quality texture images of an urban area. The image fusion can be efficiently achieved by epipolar plane image (EPI) analysis, and the shadow elimination can be successfully carried out by an illumination independent color clustering technique. The strength of this algorithm is that we can successfully fuse multiple images and eliminate shadows from the fused single image, especially in low dynamic range images, which have proven difficult using previous techniques.
基金Supported by the National Natural Science Foundation of China (No. 20076012).
文摘A surface equation of state, applicable to liquid-expanded (LE) monolayers, was derived by analyzing the Helmholtz free energy of the LE monolayers. Based on this equation, a general equation was obtained to describe all states of single-component phospholipid monolayers during comprassion. To verify the applicability of the equation, π-A isotherms of 1,2-dipalmitoylphosphatidylcholine (DPPC), 1,2-dipalmitoylphosphatidylglycerol (DPPG), and 1,2-dimyristoyphosphatildylcholine (DMPC) were measured. The comparison between model and experimental values indicates that the equation can describe the behavior of pure phospholipid monolayers.
文摘A modular flat-screen liquid crystal television display is described. The picture elements of the modules may be emissive, reflective or transmissive. The flat-screen liquid crystal television also comprised of an electrical control circuit capable of categorizing incoming television picture signals corresponding to the modules in the array and directing the electrical signals to the drive circuits of each module according to the portion of the television picture to be reproduced by the picture elements of that module. The picture elements are preferably formed in a light modulating film composed of a liquid crystal dispersion in a polymeric binder. A color display was also produced by placing a patterned red-green-blue filter adjacent the active matrix so that each picture element could also be coordinated with the color components of a color video signal.
文摘This paper analyzes the key technology of mobile GIS development, discusses the design method of mobile GIS spatial data management, visualization of spatial data And Spatial data query, tinder Object oriented mode. And we develop a set of mobile GIS basic software platform in the Android platform, and tested in the mainstream smart mobile phone with Android operating system, test results show that the software platform can run smoothly. Other users can development a variety of mobile GIS to call the platform through an application service interface.
文摘The vulnerability of Egypt to potential impacts of sea level rise has been considered. It was recognized that many locations in Egyptian Coast, on Mediterranean Sea (Mersa Matruh, Alexandria and Port Said) and on Red Sea (Hurghada), are highly vulnerable to the potential impacts of sea level rise, salt water intrusion and increase of frequency and severity of storm surges. The aim of this study is to investigate the monthly average and the variations of sea level and meteorological conditions along the Egyptian Mediterranean and north Red Sea coasts. Monthly mean cycles and correlation coefficients between MSL (Mean Sea Level) and different meteorological parameters were also calculated. The analyzed data was from 2007 to 2009 covering 3 years of hourly recorded sea level and meteorological parameters were used except for Hurghada sea level was for 2007 and 2008. Sea level harmonic analyses were done by using TOGA (Tropical Ocean and Global Atmosphere) software. Sea level variations were also computed, and it was 20.1,20, 0.1 and 55.3 cm in Alexandria, Port Said, Mersa Matruh and Hurghada respectively. The annual of the tidal constituents were computed to determine the MSL. Surge calculations were done by using TOGA software and eliminating the predicted tide from the observed sea level. The average calculated surge was also analyzed that the highest surge happened during summer and the lowest during winter in Alexandria and Port Said, while the highest surge was during winter and the lowest during summer in Hurghada. The surge variation was very weak in Mersa Matruh. The result of multiple regression analysis is a statistically significant relationship between the variables at the 99% confidence level.
基金supported by the Special Scientific Research Fund of the Meteorological Public Welfare Profession of China (Grant No.GYHY201006036)the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No.IAP09303)the Major State Basic Research Development Program of China (Grant No.2010CB428401)
文摘Based on global solar radiation and related meteorological data from 57 stations in China between 1961 and 2009, we analyze the variation of surface global solar radiation (G) and its relationship to meteorological elements using linear-trend estimation, wavelet analysis, and the Mann-Kendall test. The results show that of the 33 stations with time series longer than 45 years, G is significant at the 95% confidence level. G has a decreasing trend at many stations, but results vary across different areas. The decadal departure percentage of G increased from the 1960s to 1970s, declined gradually after the 1970s, and decreased significantly in the 1980s. In the 1990s, the trend at a few sites slightly increased. The trend of cumulative variance is of four types, i.e. rise-fall, rise-fall-slight rise, rise-fall-rise, and not obvious. For changes within a year, the most obvious decline was in winter, and the rest of the year had a slight decrease. The major cycles of annual G were 6-9, 10-13, and 29-33 a. The inflection points were mostly in the 1970s. The reasons for greater changes were complex. Relevant meteorological elements were selected and analyzed by statistical methods. Trends in climatic parameters, such as annual average percentage of sunshine, annual average wind speed, and annual average of low cloud cover, were closely related to G. Thus, this indicated the potential causes of the observed trends in G. The long-term trend for annual G in some regions was also influenced by anthro- pogenic activities. Annual average percentage of sunshine and annual average wind speed were positively correlated with annual G, respectively.