A nonlinear data analysis algorithm, namely empirical data decomposition (EDD) is proposed, which can perform adaptive analysis of observed data. Analysis filter, which is not a linear constant coefficient filter, i...A nonlinear data analysis algorithm, namely empirical data decomposition (EDD) is proposed, which can perform adaptive analysis of observed data. Analysis filter, which is not a linear constant coefficient filter, is automatically determined by observed data, and is able to implement multi-resolution analysis as wavelet transform. The algorithm is suitable for analyzing non-stationary data and can effectively wipe off the relevance of observed data. Then through discussing the applications of EDD in image compression, the paper presents a 2-dimension data decomposition framework and makes some modifications of contexts used by Embedded Block Coding with Optimized Truncation (EBCOT) . Simulation results show that EDD is more suitable for non-stationary image data compression.展开更多
Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental monitoring.The spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2001-20...Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental monitoring.The spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2001-2020 were investigated by reconstructing the MODIS Level 3 products with the data interpolation empirical orthogonal function(DINEOF)method.The reconstructed results by interpolating the combined MODIS daily+8-day datasets were found better than those merely by interpolating daily or 8-day data.Chl-a concentration in the YS and the ECS reached its maximum in spring,with blooms occurring,decreased in summer and autumn,and increased in late autumn and early winter.By performing empirical orthogonal function(EOF)decomposition of the reconstructed data fields and correlation analysis with several potential environmental factors,we found that the sea surface temperature(SST)plays a significant role in the seasonal variation of Chl a,especially during spring and summer.The increase of SST in spring and the upper-layer nutrients mixed up during the last winter might favor the occurrence of spring blooms.The high sea surface temperature(SST)throughout the summer would strengthen the vertical stratification and prevent nutrients supply from deep water,resulting in low surface Chl-a concentrations.The sea surface Chl-a concentration in the YS was found decreased significantly from 2012 to 2020,which was possibly related to the Pacific Decadal Oscillation(PDO).展开更多
The importance of accurate knowledge about available global solar radiation in the design and development of various solar energy systems cannot be overemphasized. Most of the available models for predicting global so...The importance of accurate knowledge about available global solar radiation in the design and development of various solar energy systems cannot be overemphasized. Most of the available models for predicting global solar radiation involve a plethora of input factors, some of which require special skills and equipment to measure. Such multi-factor models are complex and computationally demanding. To remove some burdens associated with such models, the use of</span><span style="font-family:Verdana;"> simplified prototypes with reduced input factors ha</span></span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> been proposed. It has </span><span style="font-family:Verdana;">been </span><span style="font-family:Verdana;">shown that a model with fewer input factors, that can be determined in a definite manner or whose attributes are directly observable, is often a better alternative. Therefore, the main object of this paper is to have models with a few variables that can easily be measured, developed for predicting global solar radiation. Two input factors</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">geographical location and season of the year</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">were considered. Using a 22-year interannual average daily insolation data from the database of the National Aeronautics and Space Administration (NASA) blended with the art of interpolation, empirical models were fashioned with </span><span style="font-family:""><span style="font-family:Verdana;">the data for the five subregions of Africa. The results of the models’ analysis indicate that the latitude component is the dominant locational factor. Furthermore, the new models exhibit optimal performance in comparison with existing </span><span style="font-family:Verdana;">models</span><span style="font-family:Verdana;"> and constitute reliable predictive tools that are suitable for estimating global solar radiation for any practical application.展开更多
This article presents a ground theory to explain why some individuals choose to be unhappy rather than happy,supported by empirical data collected from a sample of 750 professionals in Greece’s public and private sec...This article presents a ground theory to explain why some individuals choose to be unhappy rather than happy,supported by empirical data collected from a sample of 750 professionals in Greece’s public and private sectors.We begin by reviewing the existing literature on happiness and well-being,highlighting the debate between hedonic and eudaimonic perspectives.We then introduce our research questions and rationale,and describe our methods,sample,and psychometric tools used to measure happiness and other variables of interest.Our results indicate that various factors,including cultural influences,past experiences,and personal values,contribute to individuals’pursuit of unhappiness.We conclude with a thorough discussion of our results and their implications for future research and interventions aimed at promoting well-being.展开更多
The combustion of pulverized coal inevitably produces dust and other harmful substances.For these reasons,the optimization of de-dusting procedure and equipments is an aspect of crucial importance towards the final go...The combustion of pulverized coal inevitably produces dust and other harmful substances.For these reasons,the optimization of de-dusting procedure and equipments is an aspect of crucial importance towards the final goal of making this source of energy more sustainable.In the present work,the behaviour of a“bag filter”is simulated using Computational Fluid Dynamics(CFD).More specifically,three possible approaches are used,differing with respect to the level of fidelity and the partial utilization of empirical data.The outcome of these simulations is mutually compared and finally discussed critically in the light of available experimental results.展开更多
The majority of the literature on the transformation of cultural promotion space in old residential areas in the United States and abroad is written from the top-down perspective of God,such as architects,planners,dev...The majority of the literature on the transformation of cultural promotion space in old residential areas in the United States and abroad is written from the top-down perspective of God,such as architects,planners,developers,and even government officials,and only a few of them examine the designer’s work from the perspective of aborigines.To sample life and gain insight into human nature,find another means to be as near to the public as possible,listen to the voice of users,and conduct an in-depth examination of the freestyle works altered by the old residential districts through the“people’s architectural planner.”展开更多
In this paper, a varying coefficient errors-in-variables model under longitudinal data is investigated.An empirical likelihood based bias-correction approach is proposed. It is proved that the proposed statistics are ...In this paper, a varying coefficient errors-in-variables model under longitudinal data is investigated.An empirical likelihood based bias-correction approach is proposed. It is proved that the proposed statistics are asymptotically chi-squared under some mild conditions, and hence can be used to construct the confidence regions of the parameters of interest. Finite sample performance of the proposed method is illustrated in a simulation study. The proposed methods are applied to an AIDS clinical trial dataset.展开更多
The main objective of this paper is to predict the diffuse solar energy on a horizontal surface by using data of global solar energy (H) and diffuse solar energy (H<sub>d</sub>) at different selected geogr...The main objective of this paper is to predict the diffuse solar energy on a horizontal surface by using data of global solar energy (H) and diffuse solar energy (H<sub>d</sub>) at different selected geographical locations in Saudi Arabia during the period time from 1980 to 2019. The low values of the root mean square error RMSE for all correlations indicated a good agreement between the measured and calculated values of H<sub>d</sub>. The negative values of mean percentage error MPE % for all models show that for all locations, the proposed correlations slightly overestimate H<sub>d</sub>, and the absolute values of MPE never reach 1.35%. The first, second and third order correlations between the diffuse solar fraction H<sub>d</sub>/H and the clearness index K<sub>t</sub> and between the diffuse transmittance H<sub>d</sub>/H<sub>0</sub> and the sunshine hours have been proposed for the selected locations using the method of regression analysis. The differences between the measured and calculated values of H<sub>d</sub> show that a first order correlation between H<sub>d</sub>/H and K<sub>t</sub> can be used for estimating H<sub>d</sub> at the present locations with good accuracy. However, second order correlations between Hd/H or H<sub>d</sub>/H<sub>0</sub> and S/S<sub>o</sub> are recommended for estimating H<sub>d</sub> at these locations. The average annual differences between measured and calculated values of diffuse solar energy H<sub>d</sub> on horizontal at selected sites in the present research are discussed.展开更多
Missing data and time-dependent covariates often arise simultaneously in longitudinal studies,and directly applying classical approaches may result in a loss of efficiency and biased estimates.To deal with this proble...Missing data and time-dependent covariates often arise simultaneously in longitudinal studies,and directly applying classical approaches may result in a loss of efficiency and biased estimates.To deal with this problem,we propose weighted corrected estimating equations under the missing at random mechanism,followed by developing a shrinkage empirical likelihood estimation approach for the parameters of interest when time-dependent covariates are present.Such procedure improves efficiency over generalized estimation equations approach with working independent assumption,via combining the independent estimating equations and the extracted additional information from the estimating equations that are excluded by the independence assumption.The contribution from the remaining estimating equations is weighted according to the likelihood of each equation being a consistent estimating equation and the information it carries.We show that the estimators are asymptotically normally distributed and the empirical likelihood ratio statistic and its profile counterpart follow central chi-square distributions asymptotically when evaluated at the true parameter.The practical performance of our approach is demonstrated through numerical simulations and data analysis.展开更多
基金This project was supported by the National Natural Science Foundation of China (60532060)Hainan Education Bureau Research Project (Hjkj200602)Hainan Natural Science Foundation (80551).
文摘A nonlinear data analysis algorithm, namely empirical data decomposition (EDD) is proposed, which can perform adaptive analysis of observed data. Analysis filter, which is not a linear constant coefficient filter, is automatically determined by observed data, and is able to implement multi-resolution analysis as wavelet transform. The algorithm is suitable for analyzing non-stationary data and can effectively wipe off the relevance of observed data. Then through discussing the applications of EDD in image compression, the paper presents a 2-dimension data decomposition framework and makes some modifications of contexts used by Embedded Block Coding with Optimized Truncation (EBCOT) . Simulation results show that EDD is more suitable for non-stationary image data compression.
基金Supported by the Fundamental Research Funds for the Central Universities(Nos.202341017,202313024)。
文摘Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental monitoring.The spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2001-2020 were investigated by reconstructing the MODIS Level 3 products with the data interpolation empirical orthogonal function(DINEOF)method.The reconstructed results by interpolating the combined MODIS daily+8-day datasets were found better than those merely by interpolating daily or 8-day data.Chl-a concentration in the YS and the ECS reached its maximum in spring,with blooms occurring,decreased in summer and autumn,and increased in late autumn and early winter.By performing empirical orthogonal function(EOF)decomposition of the reconstructed data fields and correlation analysis with several potential environmental factors,we found that the sea surface temperature(SST)plays a significant role in the seasonal variation of Chl a,especially during spring and summer.The increase of SST in spring and the upper-layer nutrients mixed up during the last winter might favor the occurrence of spring blooms.The high sea surface temperature(SST)throughout the summer would strengthen the vertical stratification and prevent nutrients supply from deep water,resulting in low surface Chl-a concentrations.The sea surface Chl-a concentration in the YS was found decreased significantly from 2012 to 2020,which was possibly related to the Pacific Decadal Oscillation(PDO).
文摘The importance of accurate knowledge about available global solar radiation in the design and development of various solar energy systems cannot be overemphasized. Most of the available models for predicting global solar radiation involve a plethora of input factors, some of which require special skills and equipment to measure. Such multi-factor models are complex and computationally demanding. To remove some burdens associated with such models, the use of</span><span style="font-family:Verdana;"> simplified prototypes with reduced input factors ha</span></span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> been proposed. It has </span><span style="font-family:Verdana;">been </span><span style="font-family:Verdana;">shown that a model with fewer input factors, that can be determined in a definite manner or whose attributes are directly observable, is often a better alternative. Therefore, the main object of this paper is to have models with a few variables that can easily be measured, developed for predicting global solar radiation. Two input factors</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">geographical location and season of the year</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">were considered. Using a 22-year interannual average daily insolation data from the database of the National Aeronautics and Space Administration (NASA) blended with the art of interpolation, empirical models were fashioned with </span><span style="font-family:""><span style="font-family:Verdana;">the data for the five subregions of Africa. The results of the models’ analysis indicate that the latitude component is the dominant locational factor. Furthermore, the new models exhibit optimal performance in comparison with existing </span><span style="font-family:Verdana;">models</span><span style="font-family:Verdana;"> and constitute reliable predictive tools that are suitable for estimating global solar radiation for any practical application.
文摘This article presents a ground theory to explain why some individuals choose to be unhappy rather than happy,supported by empirical data collected from a sample of 750 professionals in Greece’s public and private sectors.We begin by reviewing the existing literature on happiness and well-being,highlighting the debate between hedonic and eudaimonic perspectives.We then introduce our research questions and rationale,and describe our methods,sample,and psychometric tools used to measure happiness and other variables of interest.Our results indicate that various factors,including cultural influences,past experiences,and personal values,contribute to individuals’pursuit of unhappiness.We conclude with a thorough discussion of our results and their implications for future research and interventions aimed at promoting well-being.
文摘The combustion of pulverized coal inevitably produces dust and other harmful substances.For these reasons,the optimization of de-dusting procedure and equipments is an aspect of crucial importance towards the final goal of making this source of energy more sustainable.In the present work,the behaviour of a“bag filter”is simulated using Computational Fluid Dynamics(CFD).More specifically,three possible approaches are used,differing with respect to the level of fidelity and the partial utilization of empirical data.The outcome of these simulations is mutually compared and finally discussed critically in the light of available experimental results.
文摘The majority of the literature on the transformation of cultural promotion space in old residential areas in the United States and abroad is written from the top-down perspective of God,such as architects,planners,developers,and even government officials,and only a few of them examine the designer’s work from the perspective of aborigines.To sample life and gain insight into human nature,find another means to be as near to the public as possible,listen to the voice of users,and conduct an in-depth examination of the freestyle works altered by the old residential districts through the“people’s architectural planner.”
基金Supported by National Social Science Foundation of China(16BTJ015)
文摘In this paper, a varying coefficient errors-in-variables model under longitudinal data is investigated.An empirical likelihood based bias-correction approach is proposed. It is proved that the proposed statistics are asymptotically chi-squared under some mild conditions, and hence can be used to construct the confidence regions of the parameters of interest. Finite sample performance of the proposed method is illustrated in a simulation study. The proposed methods are applied to an AIDS clinical trial dataset.
文摘The main objective of this paper is to predict the diffuse solar energy on a horizontal surface by using data of global solar energy (H) and diffuse solar energy (H<sub>d</sub>) at different selected geographical locations in Saudi Arabia during the period time from 1980 to 2019. The low values of the root mean square error RMSE for all correlations indicated a good agreement between the measured and calculated values of H<sub>d</sub>. The negative values of mean percentage error MPE % for all models show that for all locations, the proposed correlations slightly overestimate H<sub>d</sub>, and the absolute values of MPE never reach 1.35%. The first, second and third order correlations between the diffuse solar fraction H<sub>d</sub>/H and the clearness index K<sub>t</sub> and between the diffuse transmittance H<sub>d</sub>/H<sub>0</sub> and the sunshine hours have been proposed for the selected locations using the method of regression analysis. The differences between the measured and calculated values of H<sub>d</sub> show that a first order correlation between H<sub>d</sub>/H and K<sub>t</sub> can be used for estimating H<sub>d</sub> at the present locations with good accuracy. However, second order correlations between Hd/H or H<sub>d</sub>/H<sub>0</sub> and S/S<sub>o</sub> are recommended for estimating H<sub>d</sub> at these locations. The average annual differences between measured and calculated values of diffuse solar energy H<sub>d</sub> on horizontal at selected sites in the present research are discussed.
基金supported by the NNSF of China(No.11271347)the Fundamental Research Funds for the Central Universities
文摘Missing data and time-dependent covariates often arise simultaneously in longitudinal studies,and directly applying classical approaches may result in a loss of efficiency and biased estimates.To deal with this problem,we propose weighted corrected estimating equations under the missing at random mechanism,followed by developing a shrinkage empirical likelihood estimation approach for the parameters of interest when time-dependent covariates are present.Such procedure improves efficiency over generalized estimation equations approach with working independent assumption,via combining the independent estimating equations and the extracted additional information from the estimating equations that are excluded by the independence assumption.The contribution from the remaining estimating equations is weighted according to the likelihood of each equation being a consistent estimating equation and the information it carries.We show that the estimators are asymptotically normally distributed and the empirical likelihood ratio statistic and its profile counterpart follow central chi-square distributions asymptotically when evaluated at the true parameter.The practical performance of our approach is demonstrated through numerical simulations and data analysis.