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英国怎样帮助失业者再就业
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《中国集体工业》 1998年第2期47-47,共1页
英国的就业服务机构遍布全国,由全国就业眼务总局、区域局和分区局组成,其职责主要是帮助失业者就业.
关键词 求职者 失业者 职业介绍所 就业服务机构 英国 分区局 失业补偿金 住宅区绿化 专家咨询 返回工作岗位
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Suburbanization and Subcentering of Population in Beijing Metropolitan Area:A Nonparametric Analysis 被引量:3
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作者 SUN Tieshan HAN Zhenhai +1 位作者 WANG Lanlan LI Guoping 《Chinese Geographical Science》 SCIE CSCD 2012年第4期472-482,共11页
This study focuses on the suburbanization and subcentering of population and examines the nature of spatial restructuring in terms of the population distribution in the Beijing metropolitan area.Instead of the classic... This study focuses on the suburbanization and subcentering of population and examines the nature of spatial restructuring in terms of the population distribution in the Beijing metropolitan area.Instead of the classic density function approach,we employ the nonparametric analysis to characterize the spatial pattern of population densities in the Beijing metropolitan area and identify the suburban subcenters.Our findings suggest that the population has spread with rapid urban growth in the Beijing metropolitan area,and the compact urban form has been replaced by a more dispersed polycentric spatial distribution.However,compared with the decentralization of western cities,the spatial extent of the decentralization of population in the Beijing metropolitan area is quite limited.The rapid growth of population in the near suburbs has expedited the sprawl of the central city,with a larger central agglomeration of population dominating the metropolitan area.In this sense,the spatial pattern of the Beijing metropolitan area is still characterized by the continuous compactness.However,our findings do provide the evidence that the city has been turning to a polycentric structure.We find significant population subcenters have emerged in the suburbs of Beijing since the 1980s.But the polycentricity emerged in the Beijing metropolitan area is very different by nature from that observed in Western cities.The subcenters emerged are adherent to the development scheme planned for the city,so it can be referred to as the so called 'planned polycentricity'. 展开更多
关键词 SUBURBANIZATION population subcenters POLYCENTRICITY urban spatial structure Beijing metropolitan area
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Drought over China in the 21st Century: Results of RegCM3 被引量:5
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作者 LIU Ke JIANG Da-Bang MA Jian-Yong 《Atmospheric and Oceanic Science Letters》 2012年第6期509-513,共5页
Based on 150-year simulations of a regional climate model, RegCM3, under the Special Report on Emissions Scenarios (SRES) A1B scenario, the effective drought index (EDI) is used to project the future drought change in... Based on 150-year simulations of a regional climate model, RegCM3, under the Special Report on Emissions Scenarios (SRES) A1B scenario, the effective drought index (EDI) is used to project the future drought change in China. During the baseline period 1986-2005, RegCM3 was found to reliably simulate the spatial pattern of drought over the country. Over the 21st century, the regionally averaged EDI should increase, corresponding to a decrease of drought, while the probability of extreme drought events should increase. Geographically, drought should clearly increase in Northeast China, the middle and lower reaches of the Yangtze River valley, Southwest China, and southern Tibet but decrease in most parts of the rest of the country. 展开更多
关键词 China DROUGHT EDI REGCM3
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Characteristics of Permafrost along Highway G214 in the Eastern Qinghai-Tibet Plateau 被引量:5
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作者 SHENG Yu CAO Yuan-bing +3 位作者 LI Jing WU Ji-chun CHEN Ji FENG Zi-liang 《Journal of Mountain Science》 SCIE CSCD 2015年第5期1135-1144,共10页
The characteristics of the permafrost along National Highway No. 214(G214) in Qinghai province(between kilometer markers K310 and K670),including the distribution patterns of permafrost and seasonally frozen ground(SF... The characteristics of the permafrost along National Highway No. 214(G214) in Qinghai province(between kilometer markers K310 and K670),including the distribution patterns of permafrost and seasonally frozen ground(SFG), ground ice content and mean annual ground temperature(MAGT), were analyzed using a large quantity of drilling and measured ground temperature data. Three topographic units can be distinguished along the highway: the northern mountains, including Ela Mountain and Longstone Mountain; the medial alluvial plain and the southern Bayan Har Mountains.The horizontal distribution patterns of permafrost can be divided into four sections, from north to south: the northern continuous permafrost zone(K310-K460),the island permafrost zone(K460-K560), the southern continuous permafrost zone(K560-K630),and the discontinuous permafrost zone(K630-K670).Vertically, the permafrost lower limits(PLLs) of the discontinuous zone were 4200/4325 m, 4230/4350 m,and 4350/4450 m on the north-facing/south-facing slopes of Ela Mountain, Longstone Mountain and Bayan Har Mountains, respectively. The permafrost was generally warm, with MAGTs between-1.0°C and0°C in the northern continuous permafrost zone,approximately-0.5°C in the island permafrost zone,between-1.5°C and 0°C in the southern continuous permafrost zone, and higher than-0.5°C in the discontinuous permafrost zone. In contrast, the spatial variations in ground ice content were mainly controlled by the local soil water content and lithology.The relationships between the mean annual air temperature(MAAT) and the PLLs indicated that the PLLs varied between-3.3°C and-4.1°C for the northern Ela and Longstone Mountains and between-4.1°C and-4.6°C in the southern Bayan Har Mountains. 展开更多
关键词 Permafrost characteristics NationalHighway No. 214 (G214) Eastern Qinghai-TibetPlateau Qinghai-Tibet Plateau Temperature
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Shrub Communities and Environmental Variables Responsible for Species Distribution Patterns in an Alpine Zone of the Qilian Mountains, Northwest China 被引量:8
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作者 HUO Hong FENG Qi SU Yong-hong 《Journal of Mountain Science》 SCIE CSCD 2015年第1期166-176,共11页
Understanding the factors that drive variation in species distribution is a central theme of ecological research. Although several studies focused on alpine vegetation, few efforts have been made to identify the envir... Understanding the factors that drive variation in species distribution is a central theme of ecological research. Although several studies focused on alpine vegetation, few efforts have been made to identify the environmental factors that are responsible for the variations in species composition and richness of alpine shrublands using numerical methods. In the present study, we investigated vegetation and associated environmental variables from 45 sample plots in the middle Qilian Mountains of the northwestern China to classify different community types and to elucidate the species- environment relationships. We also estimated the relative contributions of topography and site conditions to spatial distribution patterns of the shrub communities using the variation partitioning. The results showed that four shrub community types were identified and striking differences in fioristic composition were found among them. Species composition greatly depended on elevation, slope, shrub cover, soil pH and organic carbon. The important determinants of species richness were soil bulk density and slope. No significant differences in species richness were detected among the community types. Topography and site conditions had almost equal effects on compositional variation. Nonetheless,a large amount of the variation in species composition remained unexplained. 展开更多
关键词 Alpine shrublands Floristic composition Cluster analysis Canonical Correspondence Analysis(CCA) Variation partitioning Species composition Species richness
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Partition airflow varying features of chaos-theory-based coalmine ventilation system and related safety forecasting and forewarning system 被引量:1
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作者 Zhang Xiaoqiang Cheng Weimin +2 位作者 Zhang Qin Yang Xinxiang Du Wenzhou 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期269-275,共7页
To realize real-time monitoring and short-term forecasting and forewarning of coalmine ventilation systems(CVS), in this paper, we first established a joint surface and underground CVS safety management system consist... To realize real-time monitoring and short-term forecasting and forewarning of coalmine ventilation systems(CVS), in this paper, we first established a joint surface and underground CVS safety management system consisting of main ventilation fan, safety-partition linked passageways, and air-required locations. We then applied chaos theory to identify the air quantity and gas concentration of underground partition boundaries, and adopted a fixed data quantity, multi-step progressive, weighted first-order local-domain method to setup a chaos prediction model and a CVS safety forecasting and forewarning system formed by the normal change level, orange forewarning level, and red alarm level. We next conduct the on-field application of the system in a coalmine in Jining, Shandong, China. The results showed that (1) in the statistical scale of 5 min, the changes in both air quantity and gas concentration along CVS partition airflow boundaries were characteristic of chaos and could be used for short-term chaos prediction, and the latter was more chaotic than the former;(2) the setup chaos prediction model had a higher prediction precision and the established safety prediction system could not only predict the variation in CVS stability but also reflect the rationality of underground mining intensity. Thus, this CVS safety forecasting and forewarning system is of better application value. 展开更多
关键词 Mine ventilation system Safety partition Reconstructed phase space Maximum Lyapunov exponent Chaos forecasting and forewarning
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Simulation Analysis on Spatial Pattern of Urban Population in Shenyang City,China in Late 20th Century 被引量:5
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作者 QIN Zhiqin ZHANG Pingyu 《Chinese Geographical Science》 SCIE CSCD 2011年第1期110-118,共9页
The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distr... The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distribution of population in the process of urban transformation, resulting in the change of urban spatial structure. Based on the sub-district data of Chinese national population censuses in 1982, 1990 and 2000, this study simulates the evolution pattern of spatial distribution of urban population in Shenyang City. Using statistical method and exploratory spatial data analysis (ESDA), we found that the population distribution, on the whole, has presented a balanced and decentralized trend since the 1980s, which characterizes with Chinese suburbanization. Furthermore, based on the investigation of the pattern of population distribution, it is concluded that the negative exponential model fitted the distribution best, and population concentration in the inner suburb kept increasing gradually, meanwhile, the spatial structure of population distribution has presented a polycentric feature since the 1980s. The parameters of the model show that population in the urban core concentrate significantly all the time. The increase of population in the inner suburb influences the population distribution pattern more and more importantly, but the concentration intensity of population cores in inner suburb is still low. 展开更多
关键词 population distribution urban spatial structure simulation analysis Shenyang City
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Research on Farmers' Medical Security Based on Supply Theory
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作者 WANG Linlin 《International English Education Research》 2017年第1期24-26,共3页
Urbanization process to change the pattern of population distribution in rural areas to strengthen the flow of farmers in the city and rural areas; national industrial structural adjustment, the gradual decline in per... Urbanization process to change the pattern of population distribution in rural areas to strengthen the flow of farmers in the city and rural areas; national industrial structural adjustment, the gradual decline in per capital income of farmers; yearly increase in medical costs, making the farmers a serious shortage of personal medical capacity, Disease caused by poverty, due to illness back to poverty "phenomenon is obvious. Based on the historical background of the development of rural medical security, based on the perspective of "supply" of modem medical service, this paper analyzes the economic factors and policies of the farmers' "difficult to see medical treatment", and the data analysis is carried out according to the latest social data. Factors, and put forward the corresponding improvement measures. 展开更多
关键词 urbanization process rural medical security supply perspective
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Spatial and Temporal Patterns of Soil Nitrogen Distribution under Different Land Uses in a Watershed in the Hilly Area of Purple Soil,China 被引量:10
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作者 YANG Xiao-lin ZHU Bo LI Yi-ling 《Journal of Mountain Science》 SCIE CSCD 2013年第3期410-417,共8页
Quantification of soil spatial and temporal variability at watershed scale is important in ecological modeling, precision agriculture, and natural resources management. The spatio-temporal variations of soil nitrogen ... Quantification of soil spatial and temporal variability at watershed scale is important in ecological modeling, precision agriculture, and natural resources management. The spatio-temporal variations of soil nitrogen under different land uses in a small watershed (12.10 km^2) in the hilly area of purple soil at the upper reaches of the Yangtze River in southwestern China were investigated by using conventional statistics, geostatistics, and a geographical information system in order to provide information for land management and control of environmental issues. A total of 552 soil samples (o to 15 cm) from 276 sites within the watershed were collected in April and August of 2o11, and analyzed for soil total nitrogen (STN) and nitrate nitrogen (NO3-N). We compared spatial variations of STN and NO3-N under different land uses as well as the temporal variations in April (dry season) and August (rainy season). Results showed that STN contents were deeply affected by land-use types; median STN values ranged from 0.94to 1.27g.kg-I, and STN contents decreased in the following order: paddy field 〉 foresfland 〉 sloping cropland. No significant difference was found for STN contents between April and August under the same land use. However, NO3- N contents were 23.26, 10.58, and 26.19 mg·kg^-1 in April, and 1.34, 8.51, and 3.00 mg·kg^-1 in August for the paddy field, sloping cropland and forestland, respectively. Nugget ratios for STN indicatedmoderate spatial dependence in the paddy field and sloping cropland, and a strong spatial dependence in forestland. The processes of nitrogen movement, transformation, absorption of plant were deeply influenced by land use types; as a result, great changes of soil nitrogen levels at spatial and temporal scales were demonstrated in the studied watershed. 展开更多
关键词 Land use Soil nitrogen Spatial variation Temporal variation Watershed scale
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Distribution of Invasive Plant Species in Relation to Environmental and Anthropogenic Factors in Five Nature Reserves in Northern China 被引量:5
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作者 张渊媛 冯金朝 +1 位作者 桑卫国 薛达元 《Journal of Resources and Ecology》 CSCD 2012年第3期278-283,共6页
The relationships between invasive plant species and environmental and anthropogenic factors were analyzed in five nature reserves in northern China. The distribution of invasive plants was analyzed using a Canonical ... The relationships between invasive plant species and environmental and anthropogenic factors were analyzed in five nature reserves in northern China. The distribution of invasive plants was analyzed using a Canonical Correspondence Analysis. Stepwise backward multiple regression was then done to identify the most important environmental and anthropogenic factors determining the richness and distribution of alien plants in the reserves. Total invasive plant richness varied was 25 species, 12 species, 13 species, five species and five species across the nature reserves. Invasive species richness decreased in response to environmental factors such as maximum temperature and minimum precipitation and increased in line with human activities, the total area of farmland and volume of freight. Tropical plant species declined from 31% to zero while the species originally from North America gradually increased. In respect of family composition of invasive species, most species belonged to the composites, whose proportion increased from 15%-40% from north to south across the five nature reserves while species from other families varied greatly along this gradient. Life-forms of invasive plant species varied between the reserves, but annual and perennial herbs were generally dominant. Pathways of such species were highly related to human activities and utilizations. 展开更多
关键词 invasive species nature reserve Canonical Correspondence Analysis (CCA) distribution pattern
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An investigation into the three-dimensional cloud structure over East Asia from the CALIPSO-GOCCP Data 被引量:5
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作者 YIN JinFang WANG DongHai +1 位作者 XU HuanBin ZHAI GuoQing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第12期2236-2248,共13页
The spatial distribution of clouds and their seasonal variations, and the three-dimensional(3D) cloud structures over East Asia have been analyzed with the CALIPSO-GOCCP data during the period from 2007 to 2012. The r... The spatial distribution of clouds and their seasonal variations, and the three-dimensional(3D) cloud structures over East Asia have been analyzed with the CALIPSO-GOCCP data during the period from 2007 to 2012. The results show that there is a large cloud fraction greater than 0.7 over southern China, and the largest cloud fraction appears in southwest China. Besides, a large cloud fraction occurs over the southeast of the Tibetan Plateau. The total and high cloud fractions show notable variations with seasons, while the middle and low cloud fractions vary a little. As for cloud vertical structure, significant differences of the cloud vertical distributions are observed between over land and ocean. Cloud fractions and the height of the maximum cloud fractions decline gradually with the increasing latitude, except for the vertical-latitude profiles over the Tibetan Plateau regions. The longitude-vertical cross sections show similar patterns from the longitude 70° E to 140° E, except the profiles with large cloud fractions over the Tibetan Plateau. From the horizontal distribution patterns and vertical structures of the clouds over East Asia, it is concluded that the huge terrain of the Tibetan Plateau has significant impacts on the cloud formation over the Tibetan Plateau region and the areas to the east. At last, the clouds from the CALIPSO-GOCCP observations are compared to those from the ERA-Interim reanalysis data. The results indicate that the ERA-Interim reanalysis data provide reasonable spatial distribution patterns and the vertical structures in terms of the total cloud fraction over East Asia. However, the total cloud fraction was underestimated about 20% by the ERA-Interim reanalysis data over most parts of East Asia, especially over the neighboring areas east of the Tibetan Plateau. Additionally, the ERA-interim reanalysis data overestimate the cloud fractions at each level in the vertical direction. 展开更多
关键词 CALIPSO cloud fraction cloud three-dimension structure ERA-interim reanalysis data
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Analysis of emergy-based metabolic efficiency and environmental pressure on the local coupling and telecoupling between urbanization and the eco-environment in the Beijing-Tianjin-Hebei urban agglomeration 被引量:25
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作者 FANG ChuangLin REN YuFei 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第6期1083-1097,共15页
We use emergy-based urban metabolism analysis in this study to investigate the local coupling and telecoupling between urbanization and the eco-environment in the Beijing-Tianjin-Hebei urban agglomeration. Our analysi... We use emergy-based urban metabolism analysis in this study to investigate the local coupling and telecoupling between urbanization and the eco-environment in the Beijing-Tianjin-Hebei urban agglomeration. Our analysis encompasses the last 35 years spanning the period between 1980 and 2014. In addition, we analyze urban metabolic efficiency and environmental pressure in these couplings. There are three main conclusions of this study. First, we show that the total metabolic emergy value of the Beijing-Tianjin-Hebei urban agglomeration has increased over the last 35 years, and that external elements have replaced internal ones as the leading contributors to urban metabolism in this region. The proportion of metabolic emergy derived from external elements increased from 30.87% in 1980 to 67.43% in 2014. The emergy extroversion ratio has continued to increase over our study period, while the development of this urban agglomeration had become progressively and more heavily reliant on external elements. Second, over the study period, the metabolic emergy intensity of elements of local coupling and telecoupling in the Beijing-Tianjin-Hebei urban agglomeration has declined at an accelerating rate, from 1.15×10^(21) Sej/100 million RMB in1980 to 9.69×10^(19) Sej/100 million RMB in 2014. This reflects a continuous increase in the economic efficiency of this area.Correspondingly, emergy use per capita increased from 7.8×10^(15) Sej/person in 1980 to 5.83×10^(16) Sej/person in 2014, suggesting a gradual rise in the level of social welfare in this urban agglomeration. However, we also observed a consistently elevated environmental loading ratio(ELR) in our analysis in terms of metabolism of local coupling and telecoupling elements. This result indicates that environmental pressure has also increased constantly within the Beijing-Tianjin-Hebei urban agglomeration. Third,our analysis shows that the ELR of metabolic emergy from internal elements increased from 8.30 in 1980 to 43.46 in 2014, while the ratio from external elements increased from 4.15 to 92.03. Thus, we quantitatively investigated the dependency of development within this urban agglomeration on external elements as well as the resultant environmental load. The conclusions of this study provide the basis for quantitative policy-making in the Beijing-Tianjin-Hebei region, optimizing economic structures, improving economic efficiency, controlling environmental pollution, and promoting the coordinated development of this region. 展开更多
关键词 URBANIZATION ECO-ENVIRONMENT Local coupling and telecoupling Total metabolic emergy value Metabolic emergy intensity Environmental pressure Beijing-Tianjin-Hebei urban agglomeration
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Stage-progressive distribution pattern of the Lungmachi black graptolitic shales from Guizhou to Chongqing, Central China 被引量:24
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作者 CHEN Xu FAN JunXuan +6 位作者 WANG WenHui WANG HongYan NIE HaiKuan SHI XueWen WEN ZhiDong CHEN DongYang LI WenJie 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第6期1133-1146,共14页
The Lungmachi Formation is widely distributed in Guizhou, Chongqing and the adjacent area. It is important for the study of Silurian biostratigraphy and shale-gas investigation. Based on those biostratigraphically wel... The Lungmachi Formation is widely distributed in Guizhou, Chongqing and the adjacent area. It is important for the study of Silurian biostratigraphy and shale-gas investigation. Based on those biostratigraphically well-studied sections from Guiyang to Huayingshan, we reveal the stage-progressive distribution pattern of the Lungmachi black shales. The distribution of the Lungmachi black shales in the studying area can be subdivided into four geographic belts from the south to the north,reflecting the joint effect of regional and global environmental changes. The graptolite depth zonation model was adopted herein to infer the water depth of major graptolite assemblages from the black shales. The changes in the water depth indicate two major stages. The first stage is named the transgressive distribution stage which ranged from the Persculptograptus persculptus Biozone(LM1, upper Hirnantian) to the Coronograptus cyphus Biozone(LM5, upper Rhuddanian), an interval mostly controlled by global sea-level rise. The second stage, ranging from the Demirastrites triangulatus Biozone(LM6, lower Aeronian) to the Spirograptus guerichi Biozone(LM9, lower Telychian), is named the regressive shrinking stage, during which the black shales were gradually replaced by mixed-facies or carbonate sediments from the south to the north, representing the effects of the persistent uplifting of the Central Guizhou Oldland. 展开更多
关键词 Lungmachi Formation Black shales Graptolite biozone Graptolite depth zonation Transgressive distribution stage Regressive shrinking stage
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