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1.
A methodology in described to forecast the “passenger intensity” of population centers and economic regions or subregions, expressed as the ratio of passenger departures to total population. Intra-regional passenger intensity in found to be closely related to income levels and to availability of a transport net. A greater complexity of factors dictates the passenger-forming role of economic regions in inter-regional traffic.  相似文献   

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Geomorphic systems are characterized by numerous, complex interrelationships between system components, and by processes and controls which may operate over different spatial scales. Factors operating at any given spatial scale can be viewed as an abstracted subset of all relationships operating at all scales. The theory that relationships which operate over spatial scales an order of magnitude different are effectively independent of each other is formally stated in terms of abstracted systems. An example is given to illustrate the use of spatial statistics to determine what constitutes a significant spatial scale difference in controls over hydraulic geometry of a desert wash.  相似文献   

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Studies of human influences on the environment may treat human agency as an imposed, exogenous source of change or disturbance, or as an intrinsic part of earth surface systems. Consideration of human influences as exogenous or endogenous to earth surface systems can affect, or even predetermine, the outcome of analyses. This is demonstrated via qualitative stability analyses of generalized mass-and-energy-flux systems. When human impacts are considered as external disturbances such systems are stable, and will regain equilibrium after changes or perturbations. Conversely, when human impacts are included as a system component, with goals of either maximizing or minimizing throughput of mass and energy, the system is inherently unstable.  相似文献   

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The area of research that is considered the proper domain of population geography is defined. In addition to an areal approach to the analysis of various aspects of population, such as growth, structure, migration and settlement patterns, there is great need for synthetic regional population studies, integrating all aspects of population within a particular territory. Causal relationships must be explained and the study of population must be related to the study of economic location.  相似文献   

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软体动物的生长线对于重建史前人类采集贝类的季节具有十分重要的作用,因而对贝壳日生长线和年生长纹的精确识别是非常必要的。对于推测狩猎采集的季节来说,根据物种的生长史来直接推算动物的死亡季节是一种令人信服的方法。Courts和Higham(1971年)曾利用贝壳生长线重建了采自潮间带的双壳贝类Chione stutchburyi(雪蛤的一种)的生长季节,  相似文献   

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《History and theory》2004,43(4):165-178
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In memory of Alina Margolis-Edelman  相似文献   

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<正>上海到处都充满着故事,走近虹口老弄堂,似乎能听到历史的声音,成片的旧城区总是带给人几许怀旧的遐思。那些年过半百的老房子里的人和相依的砖瓦一同演绎着老上海的里弄风情。如果你也像我这样眷恋旧时光的余温,就约上三五个旅伴,驻足虹口老城区,看一看旧民俗,听一听老故事,重温过往的记忆吧!我们住的酒店对面有一所老房子(高阳路167号),是上世纪初的百年老宅,我想那条街也堪称是上海老街,充满了旧时的气息,可听说过些时日就要拆了。那我还是记录下吧,这也是即将消失的老宅  相似文献   

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高海林 《史学月刊》2004,(11):95-99
从西罗马帝国灭亡到意大利统一,从中央集权到大区自治,从罗马教廷的控制到天民党的长期执政,这是发生在意大利历史发展过程中的三次传统的断裂与延续。传统的断裂与延续,是意大利历史发展的一个鲜明特征。  相似文献   

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<正>北村韩屋由一组传统民居构成,这里没有高层建筑,也看不到太多现代化的设施,全木制结构,一不留神,还以为走进了古老的高丽王朝。在首尔最热闹的钟路上,我看到许多吹笛子的中年男人,那空灵的笛音吸引了远近游客,把他们围在中央,但他们却如入定的僧人,一个眼神都不给你,仿佛他们的世界除了笛子的乐音外,更无其他。虽然地处闹市,却能让人越听越静。如果爱因斯坦的相对论果真需要一个事实去验证的话,这个时刻就是最好的证  相似文献   

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A government official outlines some of the Soviet problems of settlement to which answers are expected from population geographers. They include: restrictions on excessive growth of large cities; promotion of industrial plant location in small and medium-size cities suffering from underemployment; prediction of ultimate population of large cities; determination of the optimal size and type of rural population centers. Population geographers are called upon to study large cities with a view to determining where further concentration of industry should be prohibited, and to select small cities suitable for plant location.  相似文献   

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王林湘  周华  潘跃  魏强 《中国文化遗产》2009,(5):M0001-M0001
山海关古城独特的地理位置.不仅使它成为历史上的军事重镇.也曾是临榆县的政治,经济.文化中心和物资集散地。  相似文献   

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Bertie Ahern, the incumbent Taoiseach or Prime Minister of Ireland, was elected to a third term in the general election of 24 May 2007. While Ahern's party, Fianna Fáil, was able to retain its governing coalition, the level of support of some of the other parties changed dramatically. Fine Gael, the principal opposition party, saw its number of seats in the parliament, Dáil Éireann, increase by nineteen. Some of the minor parties did less well than expected or compared to previous elections. Only the Greens maintained their six representatives. As a result, they were rewarded with a share in the new government. This election suggests that, while Irish society is changing rapidly, the political system is changing more slowly and subtly. This article examines the election results in terms of the fate of the political parties and focuses on one constituency, Tipperary South, to illustrate trends in Irish electoral politics.  相似文献   

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In the middle of the twentieth century psychiatry underwent a transition that is often referred to as the "psychopharmacology revolution." Implicit in the term revolution is the idea that a paradigm shift occurred. Specifically, it has been argued that psychiatry abandoned the psychoanalytic paradigm in favor of a qualitatively distinct conceptual system based on brain chemistry. The validity of this view requires that psychoanalysis had the status of a paradigm. This paper presents evidence that psychoanalysis did not constitute a paradigm and that the advent of psychopharmacology was not, technically, a scientific revolution. Instead, the rise of modern psychopharmacology was the culmination of a linear growth of biological knowledge that began to develop in the nineteenth century.  相似文献   

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