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31.
Historical records indicate that the fertile soils of the western and central Wimmera Plains of Victoria, Australia formerly supported grassy woodlands on rises and flats, and grasslands on shallow depressions and clay plains. Soil type and micro-relief appear to have been the major factors that determined the distribution of these communities. Burning of the woodlands by Aborigines may have contributed to their open grassy nature. The few ungrazed remnants of Buloke (Allocasuarina luehmannii) woodland support a suite of species that are absent from or uncommon in other Buloke woodland remnants in the region. This work demonstrates that in districts where little intact native vegetation remains, investigation of the distribution and floristic composition of the pre-settlement vegetation can provide useful information for the maintenance and restoration of remnant vegetation. 相似文献
32.
ABSTRACT. This paper uses new estimates of metropolitan factor demand and output supply functions to study how federal, state, and local fiscal policies affect metropolitan economies. We illustrate our work with findings for ten metropolitan areas in five states for changes in state corporate income taxes, local property taxes, the federal corporate income tax, an investment tax credit, interest rates, public capital stocks, output prices, and tax and regulatory policies affecting gross wages. It is clear from these simulations that a policy that is nominally the same everywhere will have repercussions that vary widely across regions and cities. 相似文献
33.
Martin O 《Revue de synthèse / Centre international de synthèse》1997,118(4):457-493
The French psychologist Alfred Binet is at the origin of the development of the mental test intended for diagnosing the intellectual level of children. Initially conceived as clinical tests their importation to the United States during the 1910's has considerably altered their use, significance and interpretation. Turned into political tools by eugenicists and hereditarists and used in large-scale selection operations, the tests have changed the psychologists' conception of intelligence: initially conceived as multifacted and qualitative, intelligence had become a single quantifiable entity. Within this context, the American psychologist Louis Leon Thurstone criticized the lack of exactness of the statistical tools used in the intelligence scale. Once objectivized, his method became a general law intended to account for all mental processes. 相似文献
34.
Jean-Marc Drouin Patrick Gautier Dalché Fabien Chareix Charles Lenay Monique Cottret Bernard Vandewalle François Laplanche Françoise Waquet Agnès Spiquel Ariane Poulantzas Olivier Martin Sophie Roux Ilana Löwy Françoise Waquet Isabelle Brian Michel Cassan Jean-Marc Rohrbasser Jean-Michel Vienne Marc Renneville Bernard Lahire Mikhaäl Xifaras Bertrand Binoche Stéphane Haber Jean-François Pradeau Noël Bonneuil Marie Jaisson 《Revue de synthèse / Centre international de synthèse》1997,118(4):551-613
35.
ABSTRACT. Real variable analysis has een used to great benefit in a variety of classical problems in location theory. In this paper we explore basic complex variable techniques in one formulation of the obnoxious location problem. A general definition of center points is first given and used to formulate several alternate versions of the obnoxious location problem. A logarithmic transformation is then used to demonstrate some equivalences between these families of distinct location problems (defined via center points). A prototype logarithmic potential function which results from this formulation is then investigated, and it is demonstrated that the extremal solutions with this objective reside on the boundary of its domain of definition. An application using zero- and one-dimensional centers is discussed, and a generalization to the spatial obnoxious problem is also briefly examined. We define a zero-dimensional center as a critical point of the logarithmic potential function, and it is shown that these centers are equivalent to the solutions of the Complex Moment Problem. 相似文献
36.
Thomas Junker 《Berichte zur Wissenschaftsgeschichte》1993,16(2):163-164
37.
Traditional infrastructure evaluation focuses primarily on technical criteria, such as the completion of a designated, interconnected system of facilities or a particular project's capacity to reduce costs borne by suppliers or end users. In the contemporary policymaking environment, however, nontechnical criteria are often of great importance in determining the success or failure of a particular infrastructure enterprise. Institutional considerations, for example, can often delay the implementation of a project or undermine its effectiveness. This paper examines the importance of non-technical criteria in infrastructure evaluation through a case study of the implementation of a major highway investment program in advanced communication and control technologies, known as intelligent vehicle -highway systems (IVHS). The case study focuses on the role of institutional issues as well as environmental issues, in the implementation of IVHS in the US. surface transportation system. The case emphasizes, first, the significance of institutional and environmental issues, and second, mechanisms for evaluating these issues in the context of a major infrastructure investment program. 相似文献
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