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31.
32.
33.
根据滑坡发生的初始条件、滑坡成因及方式表象,对常见的蠕变倾覆滑坡、卸荷滑坡、震动液化平推滑坡、潜蚀塌陷滑坡、溶蚀下陷滑坡、孔隙水压浮动滑坡和人工切蚀或冲(浪)蚀—加载滑坡等机理进行了分析. 相似文献
34.
David F. Batten 《Papers in Regional Science》1993,72(2):103-112
People in different regions of the world live under different cultural and religious orders and derive various practical ethics from them. Some of these moral and religious principles are clearly more favorable for economic development than others. Yet such ethnological differences are regrettably absent from our prevailing theories of regional economic development. In this paper, culture is defined as a system of relatively slow processes of change — known as cultural arenas. A complex interface exists between these slower processes and the relatively faster ones (known as games). In attempting to assess the development prospects of any region, a key point to grasp is that this cultural interface may be self-organizing. Its future trajectory will therefore be uncertain. To the extent that the proposed system of slow processes may be construed as a region's cultural base, they may control the nature and achievable pace of that region's development.An earlier version of this paper was presented at a Conference onThe Economics of the Cities of Art, held in Venice from 13–15 May 1991. 相似文献
35.
The work was concerned with measuring natural convection through an aperture between two zones in an environmental chamber. Airflow rates between the two zones were measured using a tracer-gas decay technique, and the temperature at the centre of each zone was measured using thermocouples. Zone 1 was heated to various temperatures in the range 18–38°C using thermostatically controlled heaters. Zone 2 was unheated. A multipoint sampling unit was used to collect a tracer-gas sample from each zone. The concentration of SF6 tracer was measured using an infra-red gas analyzer. The heat and mass flow rates between the two zones were calculated from the tracer-gas concentrations and temperature differences. Results were compared with values predicted by existing algorithms for two-zone enclosures. The mass flow rate through the aperture was found to be a function of the temperature difference between the two zones. 相似文献
36.
K Piegsa 《Canadian Metallurgical Quarterly》1997,241(1579):596-7, 600-2
Personal preference rather than the existence of contraindications usually determines the contraceptive methods women choose to use. There are, however, a number of situations in which a more thorough assessment of the suitability of available methods is demanded. These cases include women with a previous history of pelvic inflammatory disease, breast-feeding women, women being given hormone replacement therapy, and women who feel that no method is appropriate for them. Women with a previous history of pelvic inflammatory disease need to avoid contracting any additional sexually transmitted disease (STD). Condom use has been shown in several studies to effectively protect against the transmission of STDs. Diaphragms are a potential alternative to condoms, but their protective effect against STDs could use further study, while spermicides may increase the effectiveness of barrier methods in preventing STDs. All currently available contraceptives, except for the combined oral contraceptive pill, are suitable for breast-feeding women. 相似文献
37.
Román Gómez Gonz ález Cosío 《International Planning Studies》1998,3(3):367-389
The concept of capacity building for environmental protection and management refers to the process by which the abilities of societies to identify and solve environmental problems are developed. This work assumes a social constructivist perspective to the process of capacity building for environmental governance and thus depicts it as critically dependent on broader processes of political and socioeconomic modernization. In an attempt to depict such a process, a heuristic device is put forward as a model of capacity analysis. A theoretical discourse and new institutionalist perspectives are used to test such a model on a theoretical plane. Some preliminary conclusions are drawn from this theoretical exercise. 相似文献
38.
《Energy Policy》2005,33(15):1957-1968
Under the sponsorship of the US Department of Energy's Office of Energy Efficiency and Renewable Energy, staff at Oak Ridge National Laboratory (ORNL) studied the Rebuild America program for the purpose of identifying key factors associated with successful operations. This involved performing a quantitative analysis of the relationships between program results and selected characteristics of the partnerships as well as soliciting opinion data from partnership representatives regarding the factors related to good performance. The statistical analysis revealed that partnership age and the number of projects per partnership were both positively related to all the results measures tested, by themselves and in the presence of each other. The factors most frequently mentioned by the interviewed partnership representatives as influencing good partnership performance were: general assistance from the Rebuild America representative; open communications among all partners; existence of a “champion” for the partnership; support from the relevant city or state government; effective marketing to attract new partners; strong community interest; quick return on investment; interaction with other community organizations; and continuity of funding. A full discussion of all study findings can be found in the ORNL Report entitled an examination of Rebuild America partnership accomplishments and the factors influencing them (ORNL/CON-490, Oak Ridge National Laboratory, Oak Ridge, TN). 相似文献
39.
40.
Hermann Knoflacher 《Sadhana》2007,32(4):293-307
Technological determinism has become a kind of religion for many people since it appears to offer solutions for societal problems
as never before in history. Transport is one of the fascinating technology branches developed during the last 200 years. Effortless
movement over long distances has become possible for car users as long as cheap fossil energy is available. However, the effect
of fast transport on urban structures and society was not taken into account when developing these technical means. Technologists
and economists have used indicators for expected benefits of these fast transport modes without taking into account the real
system effects on society and urban structures. Plausible assumptions and hopes instead of scientific understanding of the
complex system are used in practice. In contradiction to widely held beliefs of transportation planners, there is actually
no growth of mobility if counted in number of trips per person per day, no time saving by increasing speed in the system,
and no real freedom of modal choice. Modal choice is dependent on physical and other structures, the artificial environment
built by urban planners, transport experts and political decisions. The core hypothesis of traditional urban and transport
planning ‘growth of mobility’, ‘travel time saving by increasing speed’ and ‘freedom of modal choice’ are myths and do not
exist in the real urban and transport system. This is the reason why urban planning and transport planning based on traditional
non-scientific assumptions is creating continuously not only more transport problems, but also environmental and social as
well as economic problems all over the world, where these principals are applied. Urban transport planning in Europe, understanding
the transport system and the solutions are presented in this paper. 相似文献