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121.
高质量发展是中国“十四五”乃至更长时期经济社会发展的主题,也是适应社会主要矛盾变化的基本要求,更是建设社会主义现代化国家的关键路径和遵循经济实践规律的根本所在。本文从创新、协调、绿色、开放、共享5个维度构建经济高质量发展的评价指标体系,测度了2011—2018年中国31个省(自治区、直辖市)的经济高质量发展水平,在此基础上运用社会网络分析(SNA)和二次指派程序(QAP)分别对经济高质量发展的关联网络结构特征和经济高质量发展差异的作用机制进行分析。研究发现:① 空间关联网络的关联度一直为1,且网络密度稳定在0.2~0.26之间,省际经济高质量发展的空间关联网络通达性较强且存在多重叠加现象和一定的等级性,但关联紧密程度有待提高,各网络指标保持相对稳定。② 省际经济高质量发展的空间关联网络可以分为4个板块,其中以西部省份为主的“净溢出”板块获益最小;以中部省份为主的“经纪人”板块起着“中介”和“桥梁”的作用;以环渤海省份为主的“双向溢出”板块和以长三角、东南沿海省份为主的“净受益”板块在空间关联网络中的掌控和支配作用更大,且在全国经济高质量发展过程中所起的极化作用大于涓滴作用。③ 人力资本、城市化水平、金融科技和环境质量的地区差异都会直接造成地区间经济高质量发展水平的差异,人力资本差异对其贡献超过了90%。 相似文献
122.
强垂直温度梯度条件下强对流天气分析与潜势预报 总被引:9,自引:0,他引:9
采用19年3~9月常规探空观测资料,对南昌ΔT850-500≥27℃这种强垂直温度梯度与江西强对流天气过程的关系进行了相关分析,并将区域强对流天气、局部强对流天气、无强对流天气的3类情况下的中低层气压、温度、湿度、风场及稳定度进行分类合成分析,结果表明:当南昌ΔT850-500≥27℃时,且有天气系统作为触发条件时,江西强对流天气发生的概率达85%;中低层低槽和切变等影响系统、江南华南暖湿气流、河套地区的冷空气都有利于江西强对流天气出现。对典型个例的探空曲线和对流有效位能分析表明:强垂直温度梯度结合中低层高湿度是强对流天气发生的重要条件。在强对流天气潜势预报中,强垂直温度梯度有时比对流有效位能更有指示性。根据上述分析结果,建立了相应的预报流程,并在业务试用中取得较好的效果。 相似文献
123.
典型稀土矿区周边土壤中稀土元素含量及赋存形态研究 总被引:1,自引:2,他引:1
研究不同类型稀土矿区周边土壤中稀土元素(REE)的含量与形态特征,可为矿区周边污染环境治理提供理论支持与科学建议。本文采用欧盟BCR顺序提取法、电感耦合等离子体质谱测定的方法,对内蒙古白云鄂博稀土尾矿区和江西赣南稀土矿区周边6个土壤样品中15种稀土元素进行了含量及形态分析测定。结果表明:矿区周边土壤中稀土元素总量约为264~15955μg/g,明显高于全国土壤背景值(186μg/g),白云鄂博尾矿区周边土壤富集轻稀土元素,稀土元素主要以残渣态富集,占总含量的64.0%~89.4%,生物有效性较低,对环境影响较小;赣南矿区周边土壤富集重稀土元素,稀土元素的主要存在形式是弱酸提取态和可还原态,占总含量的70%以上,易发生迁移转化及对周边环境造成污染。土壤中稀土元素的形态分布与pH值有显著相关性,随着土壤pH值的降低,稀土元素的弱酸提取态含量不断升高,残渣态含量不断降低。 相似文献
124.
Trevor Fuller PhD student 《The Professional geographer》2013,65(2):272-274
A relatively simple modeling approach for estimating spatially distributed surface energy fluxes was applied to two small watersheds, one in a semi-arid climate region and one in a sub-humid region. This approach utilized a combination of ground-based meteorological data and remotely sensed data to estimate ‘instantaneous’ surface energy fluxes at the time of the satellite or aircraft overpasses. The spatial resolution in the watershed grid cells, which was on the order of 100-400 km, was selected to be compatible with ground measurements used for validation. The model estimates of surface energy fluxes compared well with ground-based measurements of surface flux (typically within approximately 40 Wm?2). The model accuracy may be slightly less for bare soil surfaces due to an overestimation of the soil heat flux. In addition to demonstrating the feasibility of computing spatially distributed values of surface energy fluxes, these maps were used to qualitatively infer the dominant factors controlling the energy fluxes for the time period shortly following precipitation events in the basins. For the semi-arid watershed, values of sensible heat flux varied considerably over the watershed and displayed a pattern very similar to that of the spatially variable cumulative precipitation for at least one to eight days prior to the image acquisition. Due to the large fraction of exposed bare soil in a semi-arid ecosystem, even very small precipitation events had a strong influence on the pattern of sensible heat fluxes observed shortly after the event (less than 24 hours). For the sub-humid watershed, the fluxes tended to be more uniform across the watershed, and were influenced by a combination of precipitation total and land cover type. 相似文献
125.
Questions of justice have been raised in recent years when contending with the social costs of urban sprawl. But this field of inquiry suffers from the difficulty of translating the abstract notion of justice into measurable spatial indices. The aim of this paper is to empirically measure the liberal notion of justice in the metropolitan region of Tel Aviv by adopting Pierre Bourdieu’s theory of three forms of capital. Under this theory, the formation of economic, cultural, and social capital in the individual’s living environment determines the person’s exposure to different sets of life-chances (i.e., capabilities), thus influencing equality of opportunity (i.e., social justice) in space. The analysis reveals that suburban inhabitants benefit from a larger accumulation of the three forms of capital than do urban inhabitants. Accumulation of these capitals has a positive effect on exposure to life-chances, thus enhancing spatial segregation between cities and suburbs. 相似文献
126.
《Geoforum》2016
This paper considers aspects of spatial justice in the processes of land acquisition for large-scale solar energy projects in the developmentalist context of India. It explores the case of one of the world’s largest solar park projects in Charanka, Gujarat. While the official rhetoric suggests an inclusive project for globally benign renewable energy production, the research reveals a more controversial land and power politics of renewable energy. It is argued, in particular, that the project increases the precariousness of vulnerable communities, who are exposed to the loss of livelihoods due to the enclosure of common land and extra-legal mechanisms through which land acquisitions for the project have reportedly taken place. This case exemplifies how solar mega-projects may manifest a regime of accumulation whereby low-carbon coalitions of interests can maximize their gains by dispossessing vulnerable social groups of their life-sustaining assets. 相似文献
127.
ABSTRACT. Between the time of its opening, in 1923, and 1956, when the last vestiges of official segregation were swept away by the courts, the Carroll Park Municipal Golf Course in Baltimore, Maryland, figured prominently in the struggle to desegregate the city's recreational facilities. In this article we use historical sources to examine how access to Carroll Park was shaped by issues of race and ethnicity during the first half of the twentieth century, focusing specifically on the role the park played in the struggle to desegregate Baltimore's golf courses. We also consider how this victory ultimately contributed to desegregation at the city's other recreational facilities, including ball fields and swimming pools. 相似文献
128.
《The Professional geographer》1984,36(3):376-412
Book Reviewed in this article: Introduction to Climatology for the Tropics . J. O. Ayoade. Conservation and Management of Natural Resources in the United States . Charles F. Bennett. The Keeping of Animals: Adaptation and Social Relations in Livestock Producing Communities . Riva Berleant-Schiller and Eugenia Shanklin, ed. The Evolution of Geographic Thought in America: A Kentucky Root Wilford A. Bladen and Pradyumna P. Karan, eds. Latin America: Geographical Perspectives , 2nd ed. Harold Blakemore and Clifford T. Smith, ed. The Rural Real Estate Market. Department of Geography Publication Series, No. 18 . Chris Bryant. Urban Geomorphology in Drylands . R. U. Cooke, D. Brunsden, J. C. Doornkamp, and D. K. C. Jones with contributions by J. Griffiths, P. Knott, R. Potter, and R. Russell. Italian Geography, 1960–1980. Meeting of the Status of the Geographic Research in Italy, 1960–1980. Treated under the auspices of Consiglio Nazionale delle Ricerche and organized by Istituto di Geografia Umana della Facoltà di Lettere e Filosofia dell'Università degli Studi di Milano , Giacomo Corna Pellecrini and Carlo Brusa, eds. The Changing Fenland . H. C. Darby. The Future for the City Centre . R. L. Davies and A. G. Champion, eds. Saudi Arabia, Energy, Developmental Planning, and Industrialization . Ragaei El Mallakh, Dorothea H. El Mallakh, eds. For We Are Sold, I and My People: Women and Industry in Mexico's Frontier . Maria Patricia Fernández-Kelly. The Great Lakes Forest: An Environmental and Social History . Susan L. Flader, ed. Regional Transformation and Industrial Revolution: A Geography of the Yorkshire Woolen Industry . Derek Gregory Crime in City Politics . Anne Heinz, Herbert Jacob and Robert L. Lineberry, eds. Revitalizing Cities . H. Briavel Holcomb and Robert A. Beauregard. Cartographic Relief Presentation . Eduard Imhof. H. J. Steward, Trans. Soviet Union: A Geographical Survey . S. V. Kalesnik and V. F. Pavlenko, ed. Cognition and Environment . Stephen Kaplan and Rachel Kaplan. Environmental Protection: The International Dimension . David A. Kay and Harold K. Jacobsen, eds. Mathematical Programming Methods for Geographers and Planners , James Killen. Gentrification Amid Urban Decline: Strategies for America's Older Cities . Michael H. Lang. The North Atlantic Sulphur System . Risto Laulajainen. The Jerusalem Cathedra: Studies in the History, Archaeology, Geography and Ethnography of the Land of Israel, Vol. 2 . Lee I. Levine ed. Jerusalem and Detroit: Recreation Planning and Management . Stanely R. Lieber and Daniel R. Fesenmaier, eds. Heartland and Hinterland: A Geography of Canada . L. D. McCann, ed. Scarborough Where We Live: The Residential Districts of Minneapolis and St. Paul . Judith A. Martin and David A. Lanegran. California: The Geography of Diversity . Crane S. Miller and Richard S. Hyslop. Palo Alto The Dilemma of Amazonian Development . Emilio F. Moran, ed. Boulder Nuclear Waste: Socioeconomic Dimensions of Long-Term Storage . Steve H. Murdock, F. Larry Leistritz, and Rita R. Hamm, eds. Boulder Communism and the Politics of Inequalities . Daniel N. Nelson, ed. The Los Angeles Metropolis . Howard J. Nelson. Dubuque An Historical Geography of Urban System Development: Tidewater Virginia in the 18th Century . James O'Mara. Procedures and Standards for a Multipurpose Cadastre . East Asia: Geographical and Historical Approaches to Foreign Area Studies . Clifton W. Pannell, ed. Dubuque Mackinder: Geography as an Aid to Statecraft . W. H. Parker. Beyond the Urban Fringe: Land Use Issues of Nonmetropolitan America . Rutherford H. Platt and George Macinko, eds. Recreation Geography of the USSR . V. S. Preobrazhensky and V. M. Krivosheyev, eds. Missouri: A Geography . Milton D. Rafferty The Invisible Farmers: Women in Agricultural Production . Carolyn E. Sachs. Cayman Islands Seashore Vegetation: A Study in Comparative Biogeography . Jonathan D. Sauer. Hillslope Materials and Processes . Michael J. Selby. Housing in Britain: The Post-War Experience . John R. Short The Study of Population: Elements, Patterns and Processes . George A. Schnell and Mark Stephen Monmonier. Columbus The Soviet Union: A Systematic Geography . Leslie Symons, ed. The Ottoman Slave Trade and Its Suppression . Ehud R. Toledano. The Impact of Recession on Industry, Employment and the Regions, 1976–1981 . Alan R. Townsend. Landslides and Their Control , 2nd ed. Quido Záruba and Vojtech Mencl. Translated from the Czech by H. Zárubová and V. Mencl. 相似文献
129.
Tips and tricks in designing management procedures 总被引:2,自引:2,他引:2
Rademeyer Rebecca A.; Plaganyi Eva E.; Butterworth Doug S. 《ICES Journal of Marine Science》2007,64(4):618-625
130.
In this paper we extend the generalized likelihood uncertainty estimation (GLUE) technique to estimate spatially distributed uncertainty in models conditioned against binary pattern data contained in flood inundation maps. Untransformed binary pattern data already have been used within GLUE to estimate domain‐averaged (zero‐dimensional) likelihoods, yet the pattern information embedded within such sources has not been used to estimate distributed uncertainty. Where pattern information has been used to map distributed uncertainty it has been transformed into a continuous function prior to use, which may introduce additional errors. To solve this problem we use here ‘raw’ binary pattern data to define a zero‐dimensional global performance measure for each simulation in a Monte Carlo ensemble. Thereafter, for each pixel of the distributed model we evaluate the probability that this pixel was inundated. This probability is then weighted by the measure of global model performance, thus taking into account how well a given parameter set performs overall. The result is a distributed uncertainty measure mapped over real space. The advantage of the approach is that it both captures distributed uncertainty and contains information on global likelihood that can be used to condition predictions of further events for which observed data are not available. The technique is applied to the problem of flood inundation prediction at two test sites representing different hydrodynamic conditions. In both cases, the method reveals the spatial structure in simulation uncertainty and simultaneously enables mapping of flood probability predicted by the model. Spatially distributed uncertainty analysis is shown to contain information over and above that available from global performance measures. Overall, the paper highlights the different types of information that may be obtained from mappings of model uncertainty over real and n‐dimensional parameter spaces. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献