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浅谈动画场景设计中“动因素”的教学
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作者 郭孝爽 《河北画报》 2020年第8期131-131,共1页
在整个动画制作流程中,动画场景设计作为其中一个重要的环节,可以说是动画片艺术风格形成的一个重要基础和前提。从中国传统动画场景中我们可以看到,其中所呈现出的画面主要以静态美为主。以水墨动画《山水情》为例,其中主要表达了一种... 在整个动画制作流程中,动画场景设计作为其中一个重要的环节,可以说是动画片艺术风格形成的一个重要基础和前提。从中国传统动画场景中我们可以看到,其中所呈现出的画面主要以静态美为主。以水墨动画《山水情》为例,其中主要表达了一种悠闲气韵和淡淡的美。随着人们生活质量和水平的日益提高,为了能够吸引更多的观众,加快了影视动画的节奏,并在动画场景设计中逐渐对其中的“动因素”提高了重视程度,“动”可以说是动画的本质,可以赋予动画活力,如果只有“画”,而没有“动”,那么就不能构成“动画”,所以必须重视场景的“动因素”。 展开更多
关键词 漫场景设计 “动因素” 教学策略
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Astronomic background of global huge earthquakes at beginning of 21st century
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作者 Hu Hui Su You-Jin 《Applied Geophysics》 SCIE CSCD 2024年第3期423-432,616,共11页
Since the beginning of the 21st century,major earthquakes have frequently occurred worldwide.To explore the impact of astronomical factors on earthquakes,in this study,the statistical analysis method of correlation is... Since the beginning of the 21st century,major earthquakes have frequently occurred worldwide.To explore the impact of astronomical factors on earthquakes,in this study,the statistical analysis method of correlation is used to systematically analyze the effects of astronomical factors,such as solar activity,Earth’s rotation,lunar declination angle,celestial tidal force,and other phenomena on M≥8 global earthquakes at the beginning of the 21st century.With regard to solar activity,this study focuses on the analysis of the 11-year and century cycles of solar activity.The causal relationship of the Earth’s rotation is not obvious in this work and previous works;in contrast,the valley period of the solar activity century cycle may be an important astronomical factor leading to the frequent occurrence of global earthquakes at the beginning of the 21st century.This topic warrants further study. 展开更多
关键词 M≥8.0 earthquake astronomical factors solar activity Earth’s rotation lunar declination angle tidal force phenomena
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Analysis of the Groundwater System Change and Driving Factors in Songnen Plain in Jilin Province 被引量:1
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作者 郭晓东 张晶 +2 位作者 田辉 朱威 张梅桂 《Agricultural Science & Technology》 CAS 2011年第5期741-744,共4页
[Objective] The aim was to provide theoretical basis for the study of underground water dynamic changes in Songnen Plain in Jilin Province.[Method] The dynamic changes and driving factors for the underground water in ... [Objective] The aim was to provide theoretical basis for the study of underground water dynamic changes in Songnen Plain in Jilin Province.[Method] The dynamic changes and driving factors for the underground water in Songnen Plain in Jilin Province was expounded.[Result] Since 1960s,the temperature in the Songnen Plain in Jilin Province increased gradually.The average temperature increased 2℃;precipitation reduced gradually.Especially,the trend of precipitation reduction in west area was more distinct;in the meantime,the development of underground water augmented gradually and reached 2 800 million m3 in 2008.Driven by many factors,regional underground water level had distinct changes.Potential water position reduced greatly in northwest fan-shaped area.The one in other places were stable and even increased in certain parts;confined water position decreased quickly in general and it increased in certain parts.[Conclusion] The general deterioration trend of underground water environment was inevitable.But,the deterioration process can be eased through scientific planning and regional underground water resources so as to realize sustainable utilization of regional underground water resources. 展开更多
关键词 Songnen Plain Groundwater dynamic Drive factor
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Study on Cloning and Polymorphism of Porcine Adiponectin Promoter 被引量:2
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作者 凌飞 汪亮亮 +2 位作者 杜红丽 李仕新 陈瑶生 《Agricultural Science & Technology》 CAS 2009年第6期53-56,共4页
[ Objective] The aim of this study was to provide a basis for study on adiponectin as a candidate gene for fat deposition. [ Method] The promoter sequence of adiponectin was obtained by porcine BAC library screening a... [ Objective] The aim of this study was to provide a basis for study on adiponectin as a candidate gene for fat deposition. [ Method] The promoter sequence of adiponectin was obtained by porcine BAC library screening and primer-walking method. The polymorphisms of adiponectin promoter from 290 pigs, including 5 breeds of Lantang pig, Large spotted pig, Large white pig, Landrace and Duroc, were analyzed with PCR-RFLP. [ Result] At SNP site of adiponectin 5'-flanking region -1 010 bp (G/A), GG genotype frequency in Chinese indigenous pigs was significantly higher than that in exotic pigs. At SNP site of adiponectin 5'-flanking region -394 bp (T/C), the genotype distribution of Chi- nese indigenous pigs was abundant, while no CC genotype was detected in exotic pigs, and T allele frequency was higher in exotic pigs. [ Conclusion] SNP site mutation of - 1 010 bp (G/A) may lead to changes of the gene transcription level, while SNP site of -394 bp (T/C) properly has no relationship with gene transcription level and fat deposition. 展开更多
关键词 PORCINE BAC library ADIPONECTIN PROMOTER SNP
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THEORETICAL AND EXPERIMENTAL STUDY ON THE PIEZOCERAMIC ACTUATING LAMINATE
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作者 万建国 陶宝祺 朱纪军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第1期90-97,共8页
Piezoelectric ceramic element (PCE) is a kind of actuator applied widely on the intelligent material & structure. Establishing the relationship between the transferring stress and the controlling signal, namely t... Piezoelectric ceramic element (PCE) is a kind of actuator applied widely on the intelligent material & structure. Establishing the relationship between the transferring stress and the controlling signal, namely the transferring and actuating equation, is a key step to analyze the actuating performance of the PCE. Based on the method of the shear lag theory, the procedure of the stress transferring is analyzed and the transferring and actuating model is established in this paper. Some measurements for PCE(PZT5) actuating the Glass Fiber/Epoxy laminate have been done to verify the model established. The experimental results show that the theoretical model agrees well with the practice. Finally, the effect of the main factors on PCE actuating the laminate is studied by using the experimental and theoretical results. 展开更多
关键词 piezoelectric ceramics LAMINATES actuate transfer affecting factors
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Nonlinear dynamic analysis of interaction between vehicle and road surfaces for 5-axle heavy truck 被引量:1
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作者 黎文琼 张建润 +1 位作者 刘晓波 王园 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期405-409,共5页
Based on the analysis of nonlinear geometric characteristics of the suspension systems and tires, a 3D nonlinear dynamic model of a typical heavy truck is established. The impact factors of dynamic tire loads, includi... Based on the analysis of nonlinear geometric characteristics of the suspension systems and tires, a 3D nonlinear dynamic model of a typical heavy truck is established. The impact factors of dynamic tire loads, including the dynamic load stress factors, and the maximal and the minimal vertical dynamic load factors, are used to evaluate the dynamic interaction between heavy vehicles and roads under the condition of random road surface roughness. Matlab/Simulink is used to simulate the nonlinear dynamic system and calculate the impact factors. The effects of different road surface conditions on the safety of vehicle movement and the durability of parts of a vehicle are analyzed, as well as the effects of different structural parameters and different vehicle speeds on road surfaces. The study results provide both the warning limits of road surface roughness and the limits of corresponding dynamic parameters for the 5-axle heavy truck. 展开更多
关键词 5-axle heavy truck nonlinear dynamics dynamic impact factor road surlhce roughness
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Analysis of Dynamics and Driving Factors of Wetland Landscape in Zoige,Eastern Qinghai-Tibetan Plateau 被引量:19
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作者 QIU Pengfei WU Ning +2 位作者 LUO Peng WANG Zuyuan LI Maihe 《Journal of Mountain Science》 SCIE CSCD 2009年第1期42-55,共14页
Zoige Wetland is one of the largest plateau wetlands in the world. This paper provides a dynamic analysis of spatial and temporal patterns of the wetland in Zoige, Eastern Qinghai-Tibetan Plateau, supported by ERDAS8.... Zoige Wetland is one of the largest plateau wetlands in the world. This paper provides a dynamic analysis of spatial and temporal patterns of the wetland in Zoige, Eastern Qinghai-Tibetan Plateau, supported by ERDAS8.7 and ArcGIS9.0. It is the first comparative analysis of a system of rapidly changing wetland with landscape patterns in Zoige, using 3 classified landsat Thematic Mapper images of 1977, 1994 and 2001. The classified images were used to generate wetland distributing maps, and shape index (S), diversity index (H), dominance index (D), evenness index (E), fragmentation index (F) and fractal dimension (Fd) were calculated and analyzed spatiotemporally across pure grazing area in Zoige for each landscape type and in different periods (before 1977, during 1977-1994 and 1994-2001), as well as the driving forces of natural and anthropogenic. The study shows that for a comprehensive understanding of the shapes and trajectories of the shrinking and desertificated land expansion of the wetland, a spatiotemporal landscape metrics analysis in different periods is an improvement than only with landscape changing rates. This type of analysis can also be used to infer underlying social, economic, and political processes that drive the observed wetland forms. The results indicate that wetland patterns can be changed over relatively short periods of time. The total area of lake reduced by 164.86 km^2, grassland extended by 141.74 km^2, semi-marsh extended by 105.94 km^2, marsh reduced by 86.00 km^2 the number of landscape patches reduced by 56, and their average area decreased by 2.68 km^2, the successions within lake, marsh, semi-marsh and grassland were found obviously. S decreased stepwise: D and F increased but H decreased: The changing rate after 1994 was 2.3 to 2.9 times greater than that before. The change of the wetland landscape patterns resulted in the interaction between socio-ceenomic and natural forces of positive and negative aspects; and natural factors affected as assistant aspect. Some important human activities in this period led to the change of the landscape patterns in this region directly. Some measurements made by government and NGO delayed the converting process partly. 展开更多
关键词 Landscape pattern driving force FRAGMENTATION MARSH PASTURE metrics Zoige Qinghai-Tibetan Plateau
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Transboundary water vulnerability and its drivers in China 被引量:21
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作者 冯彦 何大明 《Journal of Geographical Sciences》 SCIE CSCD 2009年第2期189-199,共11页
Competitive use of transboundary freshwater resources is becoming one of the key factors influencing regional peace and political relationship among states.In China, 18 major international river basins are concentrate... Competitive use of transboundary freshwater resources is becoming one of the key factors influencing regional peace and political relationship among states.In China, 18 major international river basins are concentrated in three regions, of which the total annual outflow at the border is 7320×108 m3, occupying 26.8% of the total annual runoff of China, and the inflow at the border is only 172×108 m3.In this paper, we analyzed the major drivers affecting shared water vulnerability in China, namely:(1) changes in physical conditions affecting the availability of water;(2) competing objectives between economic development and ecological conservation;(3) lack of emergency response mechanisms;(4) unsound administrative institutions;and(5) shortcomings in the development of regional cooperation based on transboundary waters.We concluded by identifying four pathways for reducing vulnerability:(1) encouraging scientific research cooperation;(2) constructing information-sharing channels;(3) establishing early-warning mechanisms;and(4) promoting further coordination and negotia-tion. 展开更多
关键词 transboundary water VULNERABILITY DRIVERS
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Change in Fresh Snow Density in Tianshan Mountains,China 被引量:2
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作者 CHEN Xia WEI Wenshou LIU Mingzhe 《Chinese Geographical Science》 SCIE CSCD 2011年第1期36-47,共12页
The fresh snow density was observed with snow analyzer (Snow Fork) at Tianshan Station for Snowcover and Avalanche Research, Chinese Academy of Sciences from February 21 to March 5, 2009. Results show that fresh snow ... The fresh snow density was observed with snow analyzer (Snow Fork) at Tianshan Station for Snowcover and Avalanche Research, Chinese Academy of Sciences from February 21 to March 5, 2009. Results show that fresh snow density increases from the 5th h to the 291st h after the snowfall, with an average rate of increase of 4.0×10-4 g/(cm3·h) (R2 = 0.943). Analysis shows that fresh snow density is negatively correlated with the compac-tion rate of fresh snow (R2 = -0.960). Inversely, it is positively correlated with fresh snow viscosity (R2 = 0.896). In relation to meteorological factors, ground temperature rising at a depth of 40 cm is the major driving factor of snow density increase. The temperature increase in fresh snow layer and the decrease in depth hoar layer have the most prominent impacts on the snow density increase in the afternoon. Principal component analysis shows that the de-terminant factors of fresh snow density change can be grouped into 3 types as follows: 1) dynamic factor contributes about 69.71% to fresh snow density change, with a significant effect from the 5th h to the 106th h after the snowfall; 2) exogenous energy factor contributes about 20.91% to it, with a significant effect at the 130th h; and c) endoge-nous energy factor contributes about 9.38% to it, with a significant effect at the 130th h and the 195th h. 展开更多
关键词 fresh snow density compaction rate energy conversion principal component analysis Tianshan Mountains China
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Soil microbial community composition and its driving factors in alpine grasslands along a mountain elevational gradient 被引量:5
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作者 CUI Hai-jun WANG Gen-xu +3 位作者 YANG Yan YANG Yang CHANG Rui-ying RAN Fei 《Journal of Mountain Science》 SCIE CSCD 2016年第6期1013-1023,共11页
Understanding the vertical distribution patterns of soil microbial community and its driving factors in alpine grasslands in the humid regions of the Tibet Plateau might be of great significance for predicting the soi... Understanding the vertical distribution patterns of soil microbial community and its driving factors in alpine grasslands in the humid regions of the Tibet Plateau might be of great significance for predicting the soil microbial community of this type of vegetation in response to environmental change. Using phospholipid fatty acids (PLFA), we investigated soil microbial community composition along an elevational gradient (3094-4131 m above sea level) on Mount Yajiageng, and we explored the impact of plant functional groups and soil chemistry on the soil microbial community. Except for Arbuscular Mycorrhizal fungi (AM fungi) biomarker 18:2ω6,9 increasing significantly, other biomarkers did not show a consistent trend with the elevational gradient. Microbial biomass quantified by total PLFAs did not show the elevational trend and had mean values ranging from 1.64 to 4.09 ktmol per g organic carbon (OC), which had the maximum value at the highest site. Bacterial PLFAs exhibited a similar trend with total PLFAs, and its mean values ranged from 0.82 to 1.81 μmol (g OC)-1. The bacterial to fungal biomass ratios had the minimum value at the highest site, which might be related to temperature and soil total nitrogen (TN). The ratios of Gram-negative to Gram-positive bacteria had a significantly negative correlation with soil TN and had the maximum value at the highest site. Leguminous plant coverage and soil TN explained 58% of the total variation in the soil microbial community and could achieve the same interpretation as the whole model. Other factors may influence the soil microbial community through interaction with leguminous plant coverage and soil TN. Soil chemistry and plant functional group composition in substantial amounts explained different parts of the variation within the soil microbial community, and the interaction between them had no impact on the soil microbial community maybe beeause long-term grazing greatly reduces litter. In sum, although there were obvious differences in soil microbial communities along the elevation gradient, there were no clear elevational trends found in general. Plant functional groups and soil chemistry respectively affect the different aspects of soil microbial community. Leguminous plant coverage and soil TN had important effects in shaping soil microbial community. 展开更多
关键词 Alpine grassland Elevational gradient Soil microbial community Phospholipid fatty acid Plant functional group Soil chemistry Variancepartitioning
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Gilbert's syndrome: High frequency of the (TA)_7 TAA allele in India and its interaction with a novel CAT insertion in promoter of the gene for bilirubin UDP-glucuronosyltransferase 1 gene 被引量:29
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作者 Shabana Farheen Sanghamitra Sengupta +5 位作者 Amal Santra Suparna Pal Gopal Krishna Dhali Meenakshi Chakravorty Partha P Majumder Abhijit Chowdhury 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第14期2269-2275,共7页
AIM: To identify the variants in U rase 1 (UGT1A1) gene in Gilbert's syndrome (GS) and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion ... AIM: To identify the variants in U rase 1 (UGT1A1) gene in Gilbert's syndrome (GS) and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion and its impact among normal controls in India. METHODS: Ninety-five GS cases and 95 normal controls were selected. Liver function and other tests were done. The promoter and all 5 exons of UGT1A1 gene were resequenced. Functional assessment of a novel trinucleotide insertion was done by in silico analysis and by estimating UGT1A1 promoter activity carried out by ludferase reporter assay of appropriate constructs in Hep G2 cell line. RESULTS: Among the GS patients, 80% were homozygous for the TA insertion, which was several-fold higher than reports from other ethnic groups. The mean UCB level was elevated among individuals with only one copy of this insertion, which was not significantly different from those with two copies. Many new DNA variants in UGT1A1 gene were discovered, including a trinucleotide (CAT) insertion in the promoter found in a subset (10%) of GS patients, but not among normal controls. In-silico analysis showed marked changes in the DNA-folding of the promoter and functional analysis showed a 20-fold reduction in transcription efficiency of UGT1A1 gene resulting from this insertion, thereby significantly elevating the UCB level. CONCLUSION: The genetic epidemiology of GS is variable across ethnic interactions among UGT1A1 groups and the epistatic promoter variants modulate bilirubin glucuronidation. 展开更多
关键词 Unconjugated hyperbilirubinemia UGT1A1 gene DNA resequencing Luciferase reporter assay
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Driving Factors for Forest Fire Occurrence in Durango State of Mexico:A Geospatial Perspective 被引量:3
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作者 Diana Avila-Flores Marin Pompa-Garcia +3 位作者 Xanat Antonio-Nemiga Dante A Rodriguez-Trejo Eduardo Vargas-Perez Javier Santillan-Perez 《Chinese Geographical Science》 SCIE CSCD 2010年第6期491-497,共7页
Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management worldwide.Identifying the driving factors and understanding the contribution of each fa... Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management worldwide.Identifying the driving factors and understanding the contribution of each factor are essential for the management of forest fire occurrence.The objective of this study is to identify variables that are spatially related to the occurrence and incidence of the forest fire in the State of Durango,Mexico.For this purpose,data from forest fire records for a five-year period were analyzed.The spatial correlations between forest fire occurrence and intensity of land use,susceptibility of vegetation,temperature,precipitation and slope were tested by Geographically Weighted Regression(GWR) method,under an Ordinary Least Square estimator.Results show that the spatial pattern of the forest fire in the study area is closely correlated with the intensity of land use,and land use change is one of the main explanatory variables.In addition,vegetation type and precipitation are also the main driving factors.The fitting model indicates obvious link between the variables.Forest fire was found to be the consequence of a particular combination of the environmental factors,and when these factors coexist with human activities,there is high probability of forest fire occurrence.Mandatory regulation of human activities is a key strategy for forest fire prevention. 展开更多
关键词 forest fire Geographically Weighted Regression(GWR) land use forest management Durango State Mexico
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Landscape Pattern Evolution Processes of Alpine Wetlands and Their Driving Factors in the Zoige Plateau of China 被引量:30
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作者 BAI Jun-hong LU Qiong-qiong +4 位作者 WANG Jun-jing ZHAO Qing-qing OUYANG Hua DENG Wei LI Ai-nong 《Journal of Mountain Science》 SCIE CSCD 2013年第1期54-67,共14页
Zoige Plateau wetlands are located in the northeastern corner of the Qinghai-Tibet Plateau.The landscape pattern evolution processes in the Zoige Plateau and their driving factors were identified by analyzing the dyna... Zoige Plateau wetlands are located in the northeastern corner of the Qinghai-Tibet Plateau.The landscape pattern evolution processes in the Zoige Plateau and their driving factors were identified by analyzing the dynamic changes in landscape modification and conversion and their dynamic rates of alpine wetlands over the past four decades.The results showed that the landscape conversion between wetlands and non-wetlands mainly occurred during the period from 1966 to 1986.The marsh wetland area converted from lake and river wetlands was larger because of swamping compared to other wetland landscapes.Meanwhile,the larger area of marsh wetlands was also converted to lake wetlands more than other types of wetlands.The modification processes mainly occurred among natural wetland landscapes in the first three periods.Obvious conversions were observed between wetland and nonwetland landscapes(i.e.,forestland,grassland,and other landscapes) in the Zoige Plateau.These natural wetland landscapes such as river,lake and marsh wetlands showed a net loss over the past four decades,whereas artificial wetland landscapes(i.e.,paddy field and reservoir and pond wetlands) showed a net decrease.The annual dynamic rate of the whole wetland landscape was 0.72%,in which the annual dynamic rate of river wetlands was the highest,followed by lake wetlands,while marsh wetlands had the lowest dynamic rate.The integrated landscape dynamic rate showed a decreasing trend in the first three periods.The changes in wetland landscape patterns were comprehensively controlled by natural factors and human activities,especially human activities play an important role in changing wetland landscape patterns. 展开更多
关键词 Zoige Plateau Alpine wetland Landscape pattern Modification Conversion Driving factors
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Driving Forces and Their Effects on Water Conservation Services in Forest Ecosystems in China 被引量:11
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作者 GONG Shihan XIAO Yang +2 位作者 XIAO Yi ZHANG Lu OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2017年第2期216-228,共13页
Identifying the driving forces that cause changes in forest ecosystem services related to water conservation is essential for the design of interventions that could enhance positive impacts as well as minimizing negat... Identifying the driving forces that cause changes in forest ecosystem services related to water conservation is essential for the design of interventions that could enhance positive impacts as well as minimizing negative impacts. In this study, we propose an assessment concept framework model for indirect-direct-ecosystem service (IN-DI-ESS) driving forces within this context and method for index construction that considers the selection of a robust and parsimonious variable set. Factor analysis was integrated into two-stage data envelopment analysis (TS-DEA) to determine the driving forces and their effects on water conservation services in forest ecosystems at the provincial scale in China. The results showed the following. 1) Ten indicators with factor scores more than 0.8 were selected as the minimum data set. Four indicators comprising population density, per capita gross domestic product, irrigation efficiency, and per capita food consumption were the indirect driving factors, and six indicators comprising precipitation, farmland into forestry or pasture, forest cover, habitat area, water footprint, and wood extraction were the direct driving forces. 2) Spearman's rank correlation test was performed to compare the overall effectiveness in two periods: stage 1 and stage 2. The calculated coefficients were 0.245, 0.136, and 0.579, respectively, whereas the tabulated value was 0.562. This indicates that the driving forces obviously differed in terms of their contribution to the overall effectiveness and they caused changes in water conservation services in different stages. In terms of the variations in different driving force effects in the years 2000 and 2010, the overall, stage 1, and stage 2 variances were 0.020, 0.065, and 0.079 in 2000, respectively, and 0.018, 0.063, and 0.071 in 2010. This also indicates that heterogeneous driving force effects were obvious in the process during the same period. Identifying the driving forces that affect service changes and evaluating their efficiency have significant policy implications for the management of forest ecosystem services. Advanced effectiveness measures for weak regions could be improved in an appropriate manner. In this study, we showed that factor analysis coupled with TS-DEA based on the IN-D1-ESS framework can increase the parsimony of driving force indicators, as well as interpreting the interactions among indirect and direct driving forces with forest ecosystem water conservation services, and reducing the uncertainty related to the internal consistency during data selection. 展开更多
关键词 driving effectiveness driving force factor analysis forest ecosystem two-stage data envelopment analysis water conservation service
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Changes in Ecosystem Service of Soil Conservation Between 2000 and 2010 and Its Driving Factors in Southwestern China 被引量:17
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作者 RAO Enming XIAO Yi +1 位作者 OUYANG Zhiyun ZHENG Hua 《Chinese Geographical Science》 SCIE CSCD 2016年第2期165-173,共9页
Human activities significantly alter ecosystems and their services; however, quantifying the impact of human activities on ecosystems has been a great challenge in ecosystem management. We used the Universal Soil Loss... Human activities significantly alter ecosystems and their services; however, quantifying the impact of human activities on ecosystems has been a great challenge in ecosystem management. We used the Universal Soil Loss Equation and county-level socioeconomic data to assess the changes in the ecosystem service of soil conservation between 2000 and 2010, and to analyze its spatial characteristics and driving factors in the southwestern China. The results showed that cropland in the southwestern China decreased by 3.74%, while urban land, forest, and grassland areas increased by 46.78%, 0.86%, and 1.12%, respectively. The soil conservation increased by 1.88 × 10^(11) kg, with deterioration only in some local areas. The improved and the degraded areas accounted for 6.41% and 2.44% of the total land area, respectively. Implementation of the Sloping Land Conversion Program and urbanization explained 57.80% and 23.90% of the variation in the soil conservation change, respectively, and were found to be the main factors enhancing soil conservation. The 2008 Wenchuan earthquake was one of the factors that led to the degradation of soil conservation. Furthermore, industrial adjustment, by increasing shares of Industry and Service and reducing those of Agriculture, has also promoted soil conservation. Our results quantitatively showed and emphasized the contributions to soil conservation improvement made by implementing ecological restoration programs and promoting urbanization. Consequently, these results provide basic information to improve our understanding of the effects of ecological restoration programs, and help guide future sustainable urban development and regional industrial restructuring. 展开更多
关键词 soil conservation ecosystem service Sloping Land Conversion Program(SLCP) ecological restoration urbanization southwestern China
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Fourth Industrial Revolution:Technological Drivers,Impacts and Coping Methods 被引量:6
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作者 LI Guoping HOU Yun WU Aizhi 《Chinese Geographical Science》 SCIE CSCD 2017年第4期626-637,共12页
The world is marching into a new development period when the digital technology,physical technology,and biological technology have achieved an unprecedented development respectively in their own fields,and at the same... The world is marching into a new development period when the digital technology,physical technology,and biological technology have achieved an unprecedented development respectively in their own fields,and at the same time their applications are converging greatly.These are the three major technological drivers for the Fourth Industrial Revolution.This paper discusses the specific technology niches of each kind technological driver behind the Fourth Industrial Revolution,and then evaluates impacts of the Fourth Industrial Revolution on global industrial,economic,and social development.At last this paper proposes possible measures and policies for both firms and governments to cope with the changes brought by the Fourth Industrial Revolution. 展开更多
关键词 Fourth Industrial Revolution technological drivers global impacts firm-level adjustments government policies
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The effect of active sitting on trunk motion 被引量:3
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作者 Henry Wang Kaitlyn J.Weiss +1 位作者 Mason C.Haggerty Jacqueline E.Heath 《Journal of Sport and Health Science》 SCIE 2014年第4期333-337,共5页
Background: Prolonged sitting is a risk factor for low-back pain. The primary purpose of this study is to determine if prolonged active sitting will result in increased trunk motion. Methods: Fifteen healthy female ... Background: Prolonged sitting is a risk factor for low-back pain. The primary purpose of this study is to determine if prolonged active sitting will result in increased trunk motion. Methods: Fifteen healthy female participants volunteered to sit for 30 vain on each of three surfaces including an air-cushion, a stability ball, and a hard surface. Trunk motion was monitored using a Vicon motion capture system, and foot center of pressure was collected with two AMTI force plates. Results: Our findings indicated that the average speed of the trunk center of mass significantly increased with seating surface compliance. There were significant differences in fight and left foot centers of pressure in the antero-posterior direction between the ball and air-cushion conditions and the ball and chair conditions. Conclusion: Active sitting results in increased trunk motion and could have a positive effect on low-back health. 展开更多
关键词 Active sitting AIR-CUSHION Center of pressure Low-back pain Stability ball Trunk motion
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Self-perceptions and social–emotional classroom engagement following structured physical activity among preschoolers: A feasibility study 被引量:5
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作者 Spyridoula Vazou Constantine Mantis +1 位作者 Gayle Luze Jacqueline S.Krogh 《Journal of Sport and Health Science》 SCIE 2017年第2期241-247,共7页
Background: The well-rounded development of the child, including physical, cognitive, emotional, and social health, may be the most efficient route to well-being and academic success. The primary goal was to investiga... Background: The well-rounded development of the child, including physical, cognitive, emotional, and social health, may be the most efficient route to well-being and academic success. The primary goal was to investigate the feasibility of implementing a 12-week structured program of physical activity(PA) incorporating cognitive, social, and emotional elements in preschool. Additionally, this study, using a within-subject design,examined the acute effects of a PA session on classroom engagement and changes on perceived competence and peer acceptance from the first to the last week of the program.Methods: Twenty-seven preschoolers(mean age = 4.2 years) completed the Pictorial Scale of Perceived Competence and Social Acceptance for Young Children before and after a twice-weekly PA program. Unobtrusive classroom observations were conducted for verbal, social, and affective engagement during the first and last week of the program, both following a structured PA session(experimental day) and on a day without PA(control day). Treatment fidelity was monitored to ensure that the intervention was delivered as designed.Results: The children exhibited longer periods of verbal and social engagement during classroom periods that followed PA sessions than on non-PA days. Children also expressed more positive affect following PA sessions during the last week of the PA program. Despite high baseline scores,perceptions of general competence increased meaningfully(η2= 0.15, p = 0.05), driven by increase in perceptions of cognitive competence(η2= 0.15,p = 0.06).Conclusion: This study demonstrates the feasibility of providing structured PA program to preschoolers. Moreover, these initial findings suggest that purposely designed, structured PA may help advance the social–emotional engagement and perceived competence of preschool children. 展开更多
关键词 Acute INTERVENTION Long-term effects Movement Peer acceptance Perceived competence
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Spatial Variability of Soil Carbon to Nitrogen Ratio and Its Driving Factors in Ili River Valley,Xinjiang,Northwest China 被引量:4
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作者 SUN Guojun LI Weihong +1 位作者 ZHU Chenggang CHEN Yaning 《Chinese Geographical Science》 SCIE CSCD 2017年第4期529-538,共10页
Soil carbon to nitrogen(C/N) ratio is one of the most important variables reflecting soil quality and ecological function,and an indicator for assessing carbon and nitrogen nutrition balance of soils.Its variation ref... Soil carbon to nitrogen(C/N) ratio is one of the most important variables reflecting soil quality and ecological function,and an indicator for assessing carbon and nitrogen nutrition balance of soils.Its variation reflects the carbon and nitrogen cycling of soils.In order to explore the spatial variability of soil C/N ratio and its controlling factors of the Ili River valley in Xinjiang Uygur Autonomous Region,Northwest China,the traditional statistical methods,including correlation analysis,geostatistic alanalys and multiple regression analysis were used.The statistical results showed that the soil C/N ratio varied from 7.00 to 23.11,with a mean value of 10.92,and the coefficient of variation was 31.3%.Correlation analysis showed that longitude,altitude,precipitation,soil water,organic carbon,and total nitrogen were positively correlated with the soil C/N ratio(P < 0.01),whereas negative correlations were found between the soil C/N ratio and latitude,temperature,soil bulk density and soil p H.Ordinary Cokriging interpolation showed that r and ME were 0.73 and 0.57,respectively,indicating that the prediction accuracy was high.The spatial autocorrelation of the soil C/N ratio was 6.4 km,and the nugget effect of the soil C/N ratio was 10% with a patchy distribution,in which the area with high value(12.00–20.41) accounted for 22.6% of the total area.Land uses changed the soil C/N ratio with the order of cultivated land > grass land > forest land > garden.Multiple regression analysis showed that geographical and climatic factors,and soil physical and chemical properties could independently explain 26.8%and 55.4% of the spatial features of soil C/N ratio,while human activities could independently explain 5.4% of the spatial features only.The spatial distribution of soil C/N ratio in the study has important reference value for managing soil carbon and nitrogen,and for improving ecological function to similar regions. 展开更多
关键词 soil C/N ratio spatial variability geostatistical analysis Cokriging interpolation multiple regression analysis Ili River valley
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Site-specific Vulnerability Assessment for Debris Flows: Two Case Studies 被引量:3
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作者 Liu Xilin 《Journal of Mountain Science》 SCIE CSCD 2006年第1期20-27,共8页
Here the vulnerability is defined as the potential total maximum losses due to a debris flow damaging event for a specific debris flow fan. The vulnerability is classified into property vulnerability and population vu... Here the vulnerability is defined as the potential total maximum losses due to a debris flow damaging event for a specific debris flow fan. The vulnerability is classified into property vulnerability and population vulnerability. Assessment indexes include the assets of buildings, traffic facilities, lifeline works, personal properties, and land resources for property vulnerability; age, education, and wealth of the inhabitants, natural population growth rate, and population density for population vulnerability. The vulnerability is expressed as the sum of the transformed values of the losses of property and population. Two study cases with post-fact damages by historic debris flow events in Sichuan of SW China are presented. 展开更多
关键词 Vulnerability to debris flow vulnerability factors case study China
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