[Objective] This comparative experiment was to explore the soil loss con- trol effects under cultivation combination of different soil and vegetation types, and to provide scientific basis for the upcoming pilot proje...[Objective] This comparative experiment was to explore the soil loss con- trol effects under cultivation combination of different soil and vegetation types, and to provide scientific basis for the upcoming pilot project of ecological recovery. [Method] Both the rudiment of water locomotion functioned by micro-landscape structures and different spatial combinations of various landscape constituents are considered, thus, the combination of multi-soil type, crop species and site conditions is designed in three different experimental sites. [Result] Soil loss estimates in experiments in South Wello significantly depended on various soil type, slope, vegetation and type of con- servation structure; grass cover tremendously reduces soil loss; legume cultivation performed better than cereal cultivation in soil loss control. [Conclusion] By conduct- ing the data analysis of the experiment, a scientific reference is proposed to the agri- culture planting and protective mode for the alleviation of water and soil loss in Amhara Region, Ethiopia.展开更多
Ray casting algorithm can obtain a better quality image in volume rendering, however, it exists some problems, such as powerful computing capacity and slow rendering speed. How to improve the re-sampled speed is a key...Ray casting algorithm can obtain a better quality image in volume rendering, however, it exists some problems, such as powerful computing capacity and slow rendering speed. How to improve the re-sampled speed is a key to speed up the ray casting algorithm. An algorithm is introduced to reduce matrix computation by matrix transformation characteristics of re-sampling points in a two coordinate system. The projection of 3-D datasets on image plane is adopted to reduce the number of rays. Utilizing boundary box technique avoids the sampling in empty voxel. By extending the Bresenham algorithm to three dimensions, each re-sampling point is calculated. Experimental results show that a two to three-fold improvement in rendering speed using the optimized algorithm, and the similar image quality to traditional algorithm can be achieved. The optimized algorithm can produce the required quality images, thus reducing the total operations and speeding up the volume rendering.展开更多
OBJECTIVE:We applied data mining techniques to the study of acupuncture as a treatment for juvenile myopia,with the aim of identifying hidden patterns in the data.METHODS:Fifty patients with juvenile myopia were selec...OBJECTIVE:We applied data mining techniques to the study of acupuncture as a treatment for juvenile myopia,with the aim of identifying hidden patterns in the data.METHODS:Fifty patients with juvenile myopia were selected and treated with acupuncture,and data mining was used to analyze the effects of treatment and the influence of behavioral variables.Clustering analysis was used to divide myopia patients into two classifications before acupuncture treatment.Artificial neural network BP algorithm was adopted to analyze the roles of different factors in changes in diopters.An association algorithm was used to analyze factors associated with the subjective experience of acupuncture and average diopter.RESULTS:The two classification results were fully consistent with the understandings of the ophthalmic circles.The duration of using the Internet and watching TV every day was the main factor that affected vision.Acupuncture feelings and therapeutic effect have a strong correlativity.A good or above experience's score of acupuncture could slow the progression of juvenile myopia.CONCLUSION:Collecting data from patients with juvenile myopia by using data mining can extract hidden potential rules and knowledge from the research evidence.The decision support can be provided to improve the doctor's clinical acupuncture treatment effects.展开更多
Land use generalization indices are critical for producing normative multi-scale land use databases and maps,but there is still not a national criterion for these indices in China.Previous studies on land use data gen...Land use generalization indices are critical for producing normative multi-scale land use databases and maps,but there is still not a national criterion for these indices in China.Previous studies on land use data generalization indices often neglect macroindices such as area proportion of land use types and map load,and also ignore landscape effects on land use generalization indices.Here we constructed an index system of land use data generalization from macro-and micro-perspectives,and examined scale and landscape effects on land use data generalization indices based on the countrywide multi-scale land use data samples.We formulated relationships between land use data generalization indices and both scale and land use pattern metrics.We defined thresholds of land use data generalization indices on scales of 1:50000,1:100000,1:250000,and 1:500000.We verified our methodology and index thresholds through generalizing a county land use database.展开更多
The aim of this paper is to describe and analyze people's confidence in political institutions in the BRICS countries: Brazil, Russia, India, China, and South Africa. I argue that the quality of macroeconomic indica...The aim of this paper is to describe and analyze people's confidence in political institutions in the BRICS countries: Brazil, Russia, India, China, and South Africa. I argue that the quality of macroeconomic indicators cannot explain the variation in political confidence between the five most dynamic new emerging economies, and that there is no substantial difference among young, middle-aged, and senior-agent groups. By combing data from the Asia Barometer Survey and the World Value Survey, the author provides two complementary approaches, one sociocultural and the other micropolitical, to reveal the factors that influence people's confidence in four major political institutions. The explanatory effects of these two approaches are mixed. Political identity and values, in most cases, have a significant impact on political confidence. On the other hand, high levels of interpersonal social trust, individual happiness, and satisfaction with living standards also show positive influences.展开更多
Longitudinal data often occur in follow-up studies, and in many situations, there may exist informative observation times and a dependent terminal event such as death that stops the follow-up. We propose a semiparamet...Longitudinal data often occur in follow-up studies, and in many situations, there may exist informative observation times and a dependent terminal event such as death that stops the follow-up. We propose a semiparametric mixed effect model with time-varying latent effects in the analysis of longitudinal data with informative observation times and a dependent terminal event. Estimating equation approaches are developed for parameter estimation, and asymptotic properties of the resulting estimators are established. The finite sample behavior of the proposed estimators is evaluated through simulation studies, and an application to a bladder cancer study is provided.展开更多
基金Supported by FAO of the United Nations under South-South Cooperation Program in Ethiopia(SSC/SPFS-FAO-ETHIOPIA-CHINA)~~
文摘[Objective] This comparative experiment was to explore the soil loss con- trol effects under cultivation combination of different soil and vegetation types, and to provide scientific basis for the upcoming pilot project of ecological recovery. [Method] Both the rudiment of water locomotion functioned by micro-landscape structures and different spatial combinations of various landscape constituents are considered, thus, the combination of multi-soil type, crop species and site conditions is designed in three different experimental sites. [Result] Soil loss estimates in experiments in South Wello significantly depended on various soil type, slope, vegetation and type of con- servation structure; grass cover tremendously reduces soil loss; legume cultivation performed better than cereal cultivation in soil loss control. [Conclusion] By conduct- ing the data analysis of the experiment, a scientific reference is proposed to the agri- culture planting and protective mode for the alleviation of water and soil loss in Amhara Region, Ethiopia.
文摘Ray casting algorithm can obtain a better quality image in volume rendering, however, it exists some problems, such as powerful computing capacity and slow rendering speed. How to improve the re-sampled speed is a key to speed up the ray casting algorithm. An algorithm is introduced to reduce matrix computation by matrix transformation characteristics of re-sampling points in a two coordinate system. The projection of 3-D datasets on image plane is adopted to reduce the number of rays. Utilizing boundary box technique avoids the sampling in empty voxel. By extending the Bresenham algorithm to three dimensions, each re-sampling point is calculated. Experimental results show that a two to three-fold improvement in rendering speed using the optimized algorithm, and the similar image quality to traditional algorithm can be achieved. The optimized algorithm can produce the required quality images, thus reducing the total operations and speeding up the volume rendering.
基金Supported by National Natural Science Foundation grant NO.40976108Public Projects of Science and Technology Ministry grant NO.201105033
文摘OBJECTIVE:We applied data mining techniques to the study of acupuncture as a treatment for juvenile myopia,with the aim of identifying hidden patterns in the data.METHODS:Fifty patients with juvenile myopia were selected and treated with acupuncture,and data mining was used to analyze the effects of treatment and the influence of behavioral variables.Clustering analysis was used to divide myopia patients into two classifications before acupuncture treatment.Artificial neural network BP algorithm was adopted to analyze the roles of different factors in changes in diopters.An association algorithm was used to analyze factors associated with the subjective experience of acupuncture and average diopter.RESULTS:The two classification results were fully consistent with the understandings of the ophthalmic circles.The duration of using the Internet and watching TV every day was the main factor that affected vision.Acupuncture feelings and therapeutic effect have a strong correlativity.A good or above experience's score of acupuncture could slow the progression of juvenile myopia.CONCLUSION:Collecting data from patients with juvenile myopia by using data mining can extract hidden potential rules and knowledge from the research evidence.The decision support can be provided to improve the doctor's clinical acupuncture treatment effects.
基金supported by National Basic Research Program of China (Grant No. 2006CB701303)National High Technology Research and Development Program of China (Grant No. 2007AA12Z225)+2 种基金National Natural Science Foundation of China (Grant Nos. 40771168, 40901188)Key Laboratory of Geo-informatics of State Bureau of Surveying and Mapping (Grant No. 200906)Fundamental Research Funds for the Central Universities (Grant No. 4082002)
文摘Land use generalization indices are critical for producing normative multi-scale land use databases and maps,but there is still not a national criterion for these indices in China.Previous studies on land use data generalization indices often neglect macroindices such as area proportion of land use types and map load,and also ignore landscape effects on land use generalization indices.Here we constructed an index system of land use data generalization from macro-and micro-perspectives,and examined scale and landscape effects on land use data generalization indices based on the countrywide multi-scale land use data samples.We formulated relationships between land use data generalization indices and both scale and land use pattern metrics.We defined thresholds of land use data generalization indices on scales of 1:50000,1:100000,1:250000,and 1:500000.We verified our methodology and index thresholds through generalizing a county land use database.
文摘The aim of this paper is to describe and analyze people's confidence in political institutions in the BRICS countries: Brazil, Russia, India, China, and South Africa. I argue that the quality of macroeconomic indicators cannot explain the variation in political confidence between the five most dynamic new emerging economies, and that there is no substantial difference among young, middle-aged, and senior-agent groups. By combing data from the Asia Barometer Survey and the World Value Survey, the author provides two complementary approaches, one sociocultural and the other micropolitical, to reveal the factors that influence people's confidence in four major political institutions. The explanatory effects of these two approaches are mixed. Political identity and values, in most cases, have a significant impact on political confidence. On the other hand, high levels of interpersonal social trust, individual happiness, and satisfaction with living standards also show positive influences.
基金supported by National Natural Science Foundation of China (Grant Nos. 11231010, 11171330 and 11201315)Key Laboratory of Random Complex Structures and Data Science, Chinese Academy of Sciences (Grant No. 2008DP173182)Beijing Center for Mathematics and Information Interdisciplinary Sciences
文摘Longitudinal data often occur in follow-up studies, and in many situations, there may exist informative observation times and a dependent terminal event such as death that stops the follow-up. We propose a semiparametric mixed effect model with time-varying latent effects in the analysis of longitudinal data with informative observation times and a dependent terminal event. Estimating equation approaches are developed for parameter estimation, and asymptotic properties of the resulting estimators are established. The finite sample behavior of the proposed estimators is evaluated through simulation studies, and an application to a bladder cancer study is provided.