The Experts below are selected from a list of 15 Experts worldwide ranked by ideXlab platform
B. Rajewska-wi?ch - One of the best experts on this subject based on the ideXlab platform.
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Beginning of the ozone recovery over Europe? ? Analysis of the total ozone data from the ground-based observations, 1964?2004
Annales Geophysicae, 2005Co-Authors: J. W. Krzy?cin, J. Jaroslawski, B. Rajewska-wi?chAbstract:The total ozone variations over Europe (~50° N) in the period 1964?2004 are analyzed for detection of signals of ozone recovery. The ozone deviations from the long-term monthly means (1964?1980) for selected European stations, where the ozone observations (by the Dobson spectrophotometers) have been carried out continuously for at least 3?4 decades, are averaged and examined by a regression model. A new method is proposed to disclose both the ozone trend variations and date of the trend turnaround. The regression model contains a piecewise linear trend component and the terms describing the ozone response to forcing by "natural" changes in the Atmosphere. Standard proxies for the dynamically driven ozone variations are used. The Multivariate Adaptive Regression Splines (MARS) methodology and principal component analysis are used to find an optimal set of the explanatory variables and the trend pattern. The turnaround of the ozone trend in 1994 is suggested from the pattern of the piecewise linear trend component. Thus, the changes in the ozone mean level are calculated over the periods 1970?1994 and 1994?2003, for both the original time series and the time series having "natural" variations removed. Statistical significance of the changes are derived by bootstrapping. A first stage of recovery (according to the definition of the International Ozone Commission), i.e. lessening of a negative trend, is found over Europe. It seems possible that the increase in the ozone mean level since 1994 of about 1?2% is due to superposition of the "natural" processes. Comparison of the total ozone ground-based network (the Dobson and Brewer spectrophotometers) and the satellite (TOMS, version 8) data over Europe shows the small bias in the mean values for the period 1996?2004, but the differences between the daily ozone values from these instruments are not trendless, and this may hamper an identification of the next stage of the ozone recovery over Europe. Keywords. Atmospheric composition and structure (Middle Atmosphere-composition and chemistry) ? Meteorology and atmospheric dynamics (Climatology, Middle Atmosphere dynamics)
R. P. Singh - One of the best experts on this subject based on the ideXlab platform.
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RETRIEVAL OF SURFACE REFLECTANCE USING SACRS2: A SCHEME FOR ATMOSPHERIC CORRECTION OF RESOURCESAT-2 AWIFS DATA
ISPRS - International Archives of the Photogrammetry Remote Sensing and Spatial Information Sciences, 2014Co-Authors: M. R. Pandya, V. N. Pathak, D. B. Shah, R. P. SinghAbstract:The Indian Remote Sensing (IRS) satellite series has been providing data since 1988 through various Earth observation missions. Before using IRS data for the quantitative analysis and parameter retrieval, it must be corrected for the atmospheric effects because spectral bands of IRS sensors are contaminated by intervening Atmosphere. Standard atmospheric correction model tuned for the IRS sensors was not available for deriving surface reflectance. Looking at this gap area, a study was carried out to develop a physicsbased method, called SACRS2- a Scheme for Atmospheric Correction of Resourcesat-2 (RS2) AWiFS data. SACRS2 is a computationally fast scheme developed for correcting large amount of data acquired by RS2-AWiFS sensor using a detailed radiative transfer model 6SV. The method is based on deriving a set of coefficients which depend on spectral bands of the RS2-AWiFS sensor through thousands of forward signal simulations by 6SV. Once precise coefficients of all the physical processes of atmospheric correction are determined for RS2-AWiFS spectral bands then a complete scheme was developed using these coefficients. Major inputs of the SACRS2 scheme are raw digital numbers recorded by RS2-AWiFS sensor, aerosol optical thickness at 550 nm, columnar water vapour content, ozone content and viewing-geometry. Results showed a good performance of SACRS2 with a maximum relative error in the SACRS2 simulations ranged between approximately 2 to 7 percent with respect to reference 6SV computations. A complete software package containing the SACRS2 model along with user guide and test dataset has been released on the website (www.mosdac.gov.in) for the researchers.
J. W. Krzy?cin - One of the best experts on this subject based on the ideXlab platform.
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Beginning of the ozone recovery over Europe? ? Analysis of the total ozone data from the ground-based observations, 1964?2004
Annales Geophysicae, 2005Co-Authors: J. W. Krzy?cin, J. Jaroslawski, B. Rajewska-wi?chAbstract:The total ozone variations over Europe (~50° N) in the period 1964?2004 are analyzed for detection of signals of ozone recovery. The ozone deviations from the long-term monthly means (1964?1980) for selected European stations, where the ozone observations (by the Dobson spectrophotometers) have been carried out continuously for at least 3?4 decades, are averaged and examined by a regression model. A new method is proposed to disclose both the ozone trend variations and date of the trend turnaround. The regression model contains a piecewise linear trend component and the terms describing the ozone response to forcing by "natural" changes in the Atmosphere. Standard proxies for the dynamically driven ozone variations are used. The Multivariate Adaptive Regression Splines (MARS) methodology and principal component analysis are used to find an optimal set of the explanatory variables and the trend pattern. The turnaround of the ozone trend in 1994 is suggested from the pattern of the piecewise linear trend component. Thus, the changes in the ozone mean level are calculated over the periods 1970?1994 and 1994?2003, for both the original time series and the time series having "natural" variations removed. Statistical significance of the changes are derived by bootstrapping. A first stage of recovery (according to the definition of the International Ozone Commission), i.e. lessening of a negative trend, is found over Europe. It seems possible that the increase in the ozone mean level since 1994 of about 1?2% is due to superposition of the "natural" processes. Comparison of the total ozone ground-based network (the Dobson and Brewer spectrophotometers) and the satellite (TOMS, version 8) data over Europe shows the small bias in the mean values for the period 1996?2004, but the differences between the daily ozone values from these instruments are not trendless, and this may hamper an identification of the next stage of the ozone recovery over Europe. Keywords. Atmospheric composition and structure (Middle Atmosphere-composition and chemistry) ? Meteorology and atmospheric dynamics (Climatology, Middle Atmosphere dynamics)
Nasution, Rachmad Saleh - One of the best experts on this subject based on the ideXlab platform.
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EVALUASI KINERJA PROGRAM STUDI EKONOMI SYARIAH FAKULTAS EKONOMI DAN BISNIS ISLAM IAIN SAMARINDA PASCA AKREDITASI
'Sekolah Tinggi Ilmu Qur an Amuntai', 2020Co-Authors: Yusran Yusran, Nasution, Rachmad SalehAbstract:This study aims to determine the perception of the IAIN lecturer at the Faculty of Economics and Islamic Business. This research method uses qualitative methods with data collection techniques such as questionnaires and data analysis using descriptive analysis. This study found that the 6 performance Standards set by BANT PT, namely Standard 1 about vision and mission, goals and objectives and achievement strategies, Standard 2 governance, leadership, management and quality assurance systems, Standard 4 human resources, and Standard 5 learning curriculum and academic Atmosphere, Standard 6 for financing facilities and infrastructure as well as information systems, and Standard 7 related to research, service and community service and collaboration in general are felt by lecturers in the satisfied or good category.
M. R. Pandya - One of the best experts on this subject based on the ideXlab platform.
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RETRIEVAL OF SURFACE REFLECTANCE USING SACRS2: A SCHEME FOR ATMOSPHERIC CORRECTION OF RESOURCESAT-2 AWIFS DATA
ISPRS - International Archives of the Photogrammetry Remote Sensing and Spatial Information Sciences, 2014Co-Authors: M. R. Pandya, V. N. Pathak, D. B. Shah, R. P. SinghAbstract:The Indian Remote Sensing (IRS) satellite series has been providing data since 1988 through various Earth observation missions. Before using IRS data for the quantitative analysis and parameter retrieval, it must be corrected for the atmospheric effects because spectral bands of IRS sensors are contaminated by intervening Atmosphere. Standard atmospheric correction model tuned for the IRS sensors was not available for deriving surface reflectance. Looking at this gap area, a study was carried out to develop a physicsbased method, called SACRS2- a Scheme for Atmospheric Correction of Resourcesat-2 (RS2) AWiFS data. SACRS2 is a computationally fast scheme developed for correcting large amount of data acquired by RS2-AWiFS sensor using a detailed radiative transfer model 6SV. The method is based on deriving a set of coefficients which depend on spectral bands of the RS2-AWiFS sensor through thousands of forward signal simulations by 6SV. Once precise coefficients of all the physical processes of atmospheric correction are determined for RS2-AWiFS spectral bands then a complete scheme was developed using these coefficients. Major inputs of the SACRS2 scheme are raw digital numbers recorded by RS2-AWiFS sensor, aerosol optical thickness at 550 nm, columnar water vapour content, ozone content and viewing-geometry. Results showed a good performance of SACRS2 with a maximum relative error in the SACRS2 simulations ranged between approximately 2 to 7 percent with respect to reference 6SV computations. A complete software package containing the SACRS2 model along with user guide and test dataset has been released on the website (www.mosdac.gov.in) for the researchers.