Glacial lakes in the High Mountain Asia(HMA)are sensitive to global warming and can result in much more severe flood disasters than some largesized lakes.An accurate and robust method for the extraction of glacial lak...Glacial lakes in the High Mountain Asia(HMA)are sensitive to global warming and can result in much more severe flood disasters than some largesized lakes.An accurate and robust method for the extraction of glacial lakes is critical to effective management of these natural water resources.Conventional methods often have limitations in terms of low spectral contrast and heterogeneous backgrounds in an image.This study presents a robust and automated method for the yearly mapping of glacial lake over a large scale,which took advantage of the complementarity between the modified normalized difference water index(MNDWI)and the nonlocal active contour model,required only local homogeneity in reflectance features of lake.The cloud computing approach with the Google Earth Engine(GEE)platform was used to process the intensive amount of Landsat 8 images from 2015 (344 path/rows and approximately 7504 scenes).The experimental results were validated by very high resolution images from Chinese GaoFen-1 (GF-1) panchromatic multi-spectral(PMS)and appeared a general good agreement.This is the first time that information regarding the spatial distribution of glacial lakes over the HMA has been derived automatically within quite a short period of time.By integrating it with the relevant indices,it can also be applied to detect other land cover types such as snow or vegetation with improved accuracy.展开更多
In recent years, public diplomacy experienced a steady and prosperous development in China. The objective of this paper is to map out the role of public diplomacy in China playing in the process of China＇s national i...In recent years, public diplomacy experienced a steady and prosperous development in China. The objective of this paper is to map out the role of public diplomacy in China playing in the process of China＇s national image construction overseas and the necessity of public diplomacy literacy education of youth especially those college students in higher education institutions. To be aware of these, it is significant and valuable in terms of the public diplomacy literacy education in college teaching in the era of new media sphere.展开更多
The study is conducted to examine the differences of gender perception among educators who are teaching in local higher learning institutions in Malaysia, in viewing their roles as the ＇~teacher＂. Several higher lea...The study is conducted to examine the differences of gender perception among educators who are teaching in local higher learning institutions in Malaysia, in viewing their roles as the ＇~teacher＂. Several higher learning institutions were randomly targeted. Several researchers were involved in the data collection by means of using questionnaires in the survey over a period of several weeks. The questionnaires were used to fred out about their academic and professional backgrounds, requiring them to list their roles pertinent to their experiences in teaching, ranked them and provided the rationale behind the choices made. Twenty-five samples were collected to scrutinize the data by categorizing the information according to gender and teaching experiences and recording the frequencies of answers. From the study, it is found that regardless of gender and teaching experiences, most participants would consider themselves as ＂Provider of knowledge＂, followed by ＂N^r＂, especially those who are relatively new in teaching. There is also an indication that teacher＇s experiences and gender might affect their perception in mirroring themselves. A larger scale of study is needed in validating the findings of this study for it to be empirical, thus promoting in-depth investigations in viewing whether gender and cultural background may be vital factors that has profound effects towards their professionalism. It is hoped that future studies will shed some light to this rather controversial claims.展开更多
The whole procedures of underwater digital terrain model (DTM) were presented by building with the global positioning system (GPS) aided high-resolution profile-scan sonar images.The algorithm regards the digital imag...The whole procedures of underwater digital terrain model (DTM) were presented by building with the global positioning system (GPS) aided high-resolution profile-scan sonar images.The algorithm regards the digital image scanned in a cycle as the raw data.First the label rings are detected with the improved Hough transform (HT) method and followed by curve-fitting for accurate location;then the most probable window for each ping is detected with weighted neighborhood gray-level co-occurrence matrix;and finally the DTM is built by integrating the GPS data with sonar data for 3D visualization.The case of an underwater trench for immersed tube road tunnel is illustrated.展开更多
An integrated and reliable phase unwrapping algorithm is proposed based on residues and blocking-lines detection, closed contour extraction and quality map ordering for the measurement of 3D shapes by Fourier-transfor...An integrated and reliable phase unwrapping algorithm is proposed based on residues and blocking-lines detection, closed contour extraction and quality map ordering for the measurement of 3D shapes by Fourier-transform profilometry (FTP). The proposed algorithm first detects the residues on the wrapped phase image, applies wavelet analysis to generate the blocking-lines that can just connect the residues of opposite polarity, then carries out the morphology operation to extract the closed contour of the shape, and finally uses the modulation intensity information and the Laplacian of Gaussian operation of the wrapped phase image as the quality map. The unwrapping process is completed from a region of high reliability to that of low reliability and the blocking-lines can prevent the phase error propagation effectively. Furthermore, by using the extracted closed contour to exclude the invalid areas from the phase unwrapping process, the algorithm becomes more efficient. The experiment shows the effec-tiveness of the new algorithm.展开更多
基金funded by the National Natural Science Foundation Project (Grant Nos. 41701481 and 41401511)
文摘Glacial lakes in the High Mountain Asia(HMA)are sensitive to global warming and can result in much more severe flood disasters than some largesized lakes.An accurate and robust method for the extraction of glacial lakes is critical to effective management of these natural water resources.Conventional methods often have limitations in terms of low spectral contrast and heterogeneous backgrounds in an image.This study presents a robust and automated method for the yearly mapping of glacial lake over a large scale,which took advantage of the complementarity between the modified normalized difference water index(MNDWI)and the nonlocal active contour model,required only local homogeneity in reflectance features of lake.The cloud computing approach with the Google Earth Engine(GEE)platform was used to process the intensive amount of Landsat 8 images from 2015 (344 path/rows and approximately 7504 scenes).The experimental results were validated by very high resolution images from Chinese GaoFen-1 (GF-1) panchromatic multi-spectral(PMS)and appeared a general good agreement.This is the first time that information regarding the spatial distribution of glacial lakes over the HMA has been derived automatically within quite a short period of time.By integrating it with the relevant indices,it can also be applied to detect other land cover types such as snow or vegetation with improved accuracy.
文摘In recent years, public diplomacy experienced a steady and prosperous development in China. The objective of this paper is to map out the role of public diplomacy in China playing in the process of China＇s national image construction overseas and the necessity of public diplomacy literacy education of youth especially those college students in higher education institutions. To be aware of these, it is significant and valuable in terms of the public diplomacy literacy education in college teaching in the era of new media sphere.
文摘The study is conducted to examine the differences of gender perception among educators who are teaching in local higher learning institutions in Malaysia, in viewing their roles as the ＇~teacher＂. Several higher learning institutions were randomly targeted. Several researchers were involved in the data collection by means of using questionnaires in the survey over a period of several weeks. The questionnaires were used to fred out about their academic and professional backgrounds, requiring them to list their roles pertinent to their experiences in teaching, ranked them and provided the rationale behind the choices made. Twenty-five samples were collected to scrutinize the data by categorizing the information according to gender and teaching experiences and recording the frequencies of answers. From the study, it is found that regardless of gender and teaching experiences, most participants would consider themselves as ＂Provider of knowledge＂, followed by ＂N^r＂, especially those who are relatively new in teaching. There is also an indication that teacher＇s experiences and gender might affect their perception in mirroring themselves. A larger scale of study is needed in validating the findings of this study for it to be empirical, thus promoting in-depth investigations in viewing whether gender and cultural background may be vital factors that has profound effects towards their professionalism. It is hoped that future studies will shed some light to this rather controversial claims.
文摘The whole procedures of underwater digital terrain model (DTM) were presented by building with the global positioning system (GPS) aided high-resolution profile-scan sonar images.The algorithm regards the digital image scanned in a cycle as the raw data.First the label rings are detected with the improved Hough transform (HT) method and followed by curve-fitting for accurate location;then the most probable window for each ping is detected with weighted neighborhood gray-level co-occurrence matrix;and finally the DTM is built by integrating the GPS data with sonar data for 3D visualization.The case of an underwater trench for immersed tube road tunnel is illustrated.
基金Project (Nos. 2007AA04Z1A5 and 2007AA01Z311) supported by the Hi-Tech Research and Development Program (863) of China
文摘An integrated and reliable phase unwrapping algorithm is proposed based on residues and blocking-lines detection, closed contour extraction and quality map ordering for the measurement of 3D shapes by Fourier-transform profilometry (FTP). The proposed algorithm first detects the residues on the wrapped phase image, applies wavelet analysis to generate the blocking-lines that can just connect the residues of opposite polarity, then carries out the morphology operation to extract the closed contour of the shape, and finally uses the modulation intensity information and the Laplacian of Gaussian operation of the wrapped phase image as the quality map. The unwrapping process is completed from a region of high reliability to that of low reliability and the blocking-lines can prevent the phase error propagation effectively. Furthermore, by using the extracted closed contour to exclude the invalid areas from the phase unwrapping process, the algorithm becomes more efficient. The experiment shows the effec-tiveness of the new algorithm.
