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101.
Hongrun Ju Lijun Zuo Jinfeng Wang Shengrui Zhang Xiao Wang 《International journal of geographical information science》2016,30(11):2188-2207
Scientific interpretation of the driving forces of built-up land expansion is essential to urban planning and policy-making. In general, built-up land expansion results from the interactions of different factors, and thus, understanding the combined impacts of built-up land expansion is beneficial. However, previous studies have primarily been concerned with the separate effect of each driver, rather than the interactions between the drivers. Using the built-up land expansion in Beijing from 2000 to 2010 as a study case, this research aims to fill this gap. A spatial statistical method, named the geographical detector, was used to investigate the effects of physical and socioeconomic factors. The effects of policy factors were also explored using physical and socioeconomic factors as proxies. The results showed that the modifiable areal unit problem existed in the geographical detector, and 4000 m might be the optimal scale for the classification performed in this study. At this scale, the interactions between most factors enhanced each other, which indicated that the interactions had greater effects on the built-up land expansion than any single factor. In addition, two pairs of nonlinear enhancement, the greatest enhancement type, were found between the distance to rivers and two socioeconomic factors: the total investment in fixed assets and GDP. Moreover, it was found that the urban plans, environmental protection policies and major events had a great impact on built-up land expansion. The findings of this study verify that the geographical detector is applicable in analysing the driving forces of built-up land expansion. This study also offers a new perspective in researching the interactions between different drivers. 相似文献
102.
This research aims to provide insight regarding Wal-Mart's retail development strategy in its expansion across the continental United States. The study examines store location patterns and relationships between Wal-Mart's store and distribution center locations and markets. The study shows that, although radial expansion is broadly characteristic of the dense store patterns that have been well established for Wal-Mart at the national level, expansion patterns at the regional level are consistent with a selective process based on factors other than store density. These results provide a new perspective on Wal-Mart's expansion, providing insights of value to retail practitioners and local government. 相似文献
103.
1 INTRODUCTIONThe South China Sea (SCS) is a semi-enclosedmarginal sea in western North Pacific Ocean withvery complex topography and is the important pas-sage connecting the Pacific and Indian Oceans. Ithas great impact to the global climate and a greatinterest of many oceanography researchers. Twodominant surface hydrographic and circulation fea-tures in the northern SCS are a strong fresh waterexpansion and a warm and high-salinity seawaterintrusion such as the SCS Diluted Water… 相似文献
104.
E. García L. De Haro C. O'Sullivan G. Cahill J. A. López Fernández F. Tercero B. Galocha J. L. Besada 《Experimental Astronomy》2003,15(3):173-193
A classical radioastronomy receiver is fed with a corrugated horn and an independent lens, both placed in a cryostat to lower
the noise temperature. The beam is focused and directed using a combination of elliptical and plane mirrors. This paper proposes
modifying the initial feeding system by placing the lens onto the horn aperture, thereby allowing a size reduction of the
horn and lens, and a simplification of their mechanical design. The profiled lens is shaped to correct the phase error on
the horn aperture. A quasi-optical model of the horn-plus-lens system has been developed using a Beam Mode Expansion (BME).
Results using both a hyperbolic-planar lens and a spherical-elliptical lens, as well as results obtained by using Geometrical
Optics (GO) with a Kirchoff–Huygens integration to get the far-field pattern, have been compared with measurements. As a direct
application, a full focusing system for the new 40-m radiotelescope at the “Centro Astronómico de Yebes” is presented for
the 22, 30 and 45 GHz bands. This paper has developed a QO model for a corrugated conical horn with a phase-correcting lens.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
105.
106.
《The Professional geographer》1982,34(3):352-379
Books reviewed in this article: Aerial Photography and Remote Sensing Aerial photography and image interpretation for Resource Management . DAVID P. PAINE . Analytical Models and Techniques Spatial Processes Models and Applications A. D. CLIFF AND J. K. ORD Quantitative and Statistical Approaches to Geography: A Practical Manual JOHN A. MATTHEWS . Cartography and Maps Map Data Processing . HERBERT FREEMAN AND GOFFREDO G. PIERONI , eds. Computer-assisted Cartography: Principles and Prospects, 1982 . MARK S. MONMONIER . Cultural Navajo Architecture: Forms, History, Distributions . STEPHEN C. JETT AND VIRGINIA E . SPENCER . Rational Landscapes and Humanistic Geography . EDWARD RELPH . Economic The Structure and Control of a State Economy . W. L. L'ESPERANCE . Economic Geography . JAMES O. WHEELER AND PETER O. MULLER . The Myth of the Family Farm: Agribusiness Dominance of U.S. Agriculture . INGOLF VOCELER . Libya: The Experience of Oil . J. A. ALLEN . Geography of Public Finance, Welfare Under Fiscal Federalism and local Government Finance . ROBERT BENNETT . Environmental Management, Resources, and Systems Mountains and Man . LARRY W. PRICE . Environmental Geology . DONALD R. COATES . An Introduction to Environmental Systems . G. H. DURY . The Environment: Chinese and American Views . Edited by LAURENCE J. C. MA AND ALLEN G. NOBLE . Land Use in America . RICHARD H. JACKSON . Medical Conceptual and Methodological Issues in Medical Geography . MELINDA S. MEADE (ed.). Philosophy and Geographic Thought Birds in Egg/Eggs in Bird . GUNNAR OLSSON . PhysicaI Climatology: Selected Applications . J. E. OLIVER . Geomorphological Techniques . ANDREW GOUDIE (ed.). Political Politics, Geography and Behaviour . RICHARD MUIR AND RONAN PADDISON . The State of the World Atlas . MICHAEL KIDRON AND RONALD SECAL . Population The Population of the South . DUDLEY L. POSTON , JR . AND ROBERT H. WELLER , eds. Regional Latin America: Economic Development and Regional Differentiation . ARTHUR MORRIS . Developing the Amazon . EMILIO F. MORAN . Western Europe: A Systematic Human Geography . BRIAN W. ILBERY . Settlement Systems in Sparsely Settled Regions: The United States and Australia . RICHARD E. LONSDALEAND JOHN H. HOLMES , eds. African Perspectives: The Economic Geography of Nine African States . HARM DE BUJ AND ESMOND MARTIN , eds. Rural Nonmetropolitan America in Transition . AMOS H. HAWLEY AND SARA MILLS MAZIE , eds. Social Crime and Environment . R. NORMAN DAVIDSON . The Ghetto: Readings with Interpretations . JOE T. DARDEN , ed. Urban Urban Problems and Planning in the Developed World . MICHAEL PACIONE (ed.) Problems and Planning in Third World Cities . Edited by MICHAEL PACIONE . The City in West Europe . D. BURTENSHAW , M. BATEMAN , AND C. J. ASHWORTH . 相似文献
107.
We discuss the question of loss of angular momentum through coronal expansion. From a large volume of data on Type-1 cometary tails we have confirmed the presence of a tangential component in the coronal expansion, which has not only a stochastic component but also a constant component of 9.8 km/s. Through coronal expansion the Sun has lost 80% of its angular momentum since it evolved on to the main sequence and the angular velocity of the Sun is decreasing exponentially. This result should have a large effect on the dynamical evolution of the Sun. 相似文献
108.
北京城市边缘区非农产业活动特征与形成机制* 总被引:2,自引:1,他引:1
考察了北京主城边缘区的非农产业结构与空间特征,揭示了二者的交互演进过程:非农产业的发展是城市边缘区形成的重要标志,产业结构的升级促进了边缘区的圈层扩展和空间演进;边缘区的外移过程中,制造业具有稳定的优势,交运仓储、生产资料租赁等传统生产者服务业的优势也随之强化,但空间黏滞性较强的旅游、体育等行业则促进了边缘区产业结构的时相差异性。文章对城市边缘区"年轮式"的圈层扩展进行了定量实证分析,并将其实现的微观路径归纳为飞地式、轴向、填充式和外推式等四种扩展模式。城市规划、城郊高速公路和开发区建设、地价和综合环境的改善是城市边缘区产业空间演变的重要动力。城市空间优化和产业结构调整的结合是解决边缘区产业、空间和社会问题的有效途径。 相似文献
109.
Using a 12th order expansion of the perturbative potential in powers of the eccentricities and the inclinations, we study
the secular effects of two non-coplanar planets which are not in mean–motion resonance. By means of Lie transformations (which
introduce an action–angle formulation of the Hamiltonian), we find the four fundamental frequencies of the 3-D secular three-body
problem and compute the long-term time evolutions of the Keplerian elements. To find the relations between these elements,
the main combinations of the fundamental frequencies common to these evolutions are identified by frequency analysis. This
study is performed for two different reference frames: a general one and the Laplace plane. We underline the known limitations
of the linear Laplace–Lagrange theory and point out the great sensitivity of the 3-D secular three-body problem to its initial
values. This analytical approach is applied to the exoplanetary system Andromedae in order to search whether the eccentricities evolutions and the apsidal configuration (libration of ) observed in the coplanar case are maintained for increasing initial values of the mutual inclination of the two orbital
planes.
Anne-Sophie Libert is FNRS Research Fellow. 相似文献
110.
黄淮海平原农区典型村庄用地扩展及其动力机制 总被引:17,自引:1,他引:16
以地处黄淮海平原农区的禹城市伦镇赵庄村为典型案例,利用高分辨率航空遥感数据为基本信息源,结合村庄逐户调查数据,通过土地利用分类与制图,定量研究典型村庄用地格局特征、扩展模式及其动力机制。结果表明:赵庄村土地利用呈"耕地—作业空间—居住空间"的圈层式空间格局。2008年村庄用地规模比1967年增加了1.26倍,主要表现为宅基地的扩展和打谷场用地增长,1985~1990年村庄用地扩展速度最快,村庄用地在空间上向西和向南方向扩展显著。村庄用地扩展主要表现为渐进式蔓延扩展、突变式非地扩展和填充式补充扩展三个阶段。农户居住需求增长与农业生产规模扩大是村庄用地扩展的内生动力,村庄内部条件与外围环境的巨大反差是村庄用地向外扩展的外部环境动力,农户收入增长为村庄用地扩展提供了经济基础,而村庄土地规划缺失与管理缺位使村庄用地扩展失去约束力,这些因素相互作用,共同驱动村庄用地扩展。最后,针对村庄用地扩展存在的问题,提出了促进村庄土地可持续利用的对策建议。 相似文献