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61.
高新技术产业集聚的城市化响应与反馈机制研究 总被引:1,自引:0,他引:1
高新技术产业集聚与城市化存在互动机制。一方面,高新技术产业结构效应影响了城市化动力机制,集聚效应则促进了城市外部经济的发展,使城市化表现出不同的模式特征和地域特征;另一方面,城市化促进了高新技术发展所需要素资源的聚集与流动,为高新技术产业集聚提供人力资本保障,还为高新技术企业提供创新的源动力。文章以苏州高新区的高新技术产业发展和城市化互动关系佐证了这一理论,并认为建立二者之间切实可行的调控模式是当务之急。 相似文献
62.
20世纪90年代以来中外区域规划研究的对比分析 总被引:1,自引:0,他引:1
区域规划是国家政府进行区域管理的重要手段和方式之一。为了落实科学发展观和对区域发展有效宏观调控,区域规划成为国家“十一五”规划的重要内容。本文对比分析了1990年代以来国外区域规划研究的主要进展、以及我国区域规划研究的特点与不足,以期为推动我国当前新一轮区域规划的理论研究和实践创新提供有益启示。 相似文献
63.
国内外旅游解说研究进展综述 总被引:14,自引:0,他引:14
本文对国外旅游解说系统研究从旅游解说的起源、原理、内涵、框架、功能、受众类型、解说方式、解说规划等方面进行了全面的总结,综合了国内旅游研究的研究现状与趋势。寻找出国内解说研究与国外解说研究的差距,借此推动国内的旅游解说系统研究,从而更好地为旅游规划、旅游业的可持续发展和游客管理服务。 相似文献
64.
A sequential waveform method is developed to simulate the seismic response of basin-edge structure excited by a plane incident P-wave. The full procedure involves: (a) a previous parameterization of the investigated model using the seismic wave velocities and depths of the sedimentary stratifications; (b) an input motion determined from the records at stations installed on hard rock; (c) forward computation of the P-SV elastic wave field by means of a two-dimensional finite difference (FD) method; (d) the optimization of the model vector using simulated annealing technique and comparing the simulated seismic response of the tested structure with the observed wave field; (e) the correction of the initial model by trial-and-error by testing the differences between synthetics and observed data, and (f) the final solution obtained by iteration using the conjugate gradient algorithm. The search of an optimal basin-edge model has been parallel processed by varying the shapes and velocities of strata on the basis of the fitting of relative timing, amplitude and phase between the output and the observed data. The input motion and sensitivity have been checked and the validity of the method has been demonstrated by numeric analysis. Using the teleseismic records generated by 7 earthquakes recorded at 26 broadband seismic stations, we have studied the seismic velocity structure of the southern edge of the Jiyang depression located in the Bohai Bay basin, northern China. Two cross sections show an agreement between the velocity results and the geological sections available in the region. In addition, we obtain evidence of three hidden faults under the sections and features that suggest major extensions at the Paleogene. 相似文献
65.
The evaluation of seismic site response in the urban area of Catania was tackled by selecting test areas having peculiar lithological
and structural features, potentially favourable to large local amplifications of ground motion. The two selected areas are
located in the historical downtown and in the northern part of Catania where the presence of a fault is evident. Site response
was evaluated using spectral ratio technique taking the horizontal- to-vertical component ratio of ambient noise. Inferences
from microtremor measurements are compared with results from synthetic accelerograms and response spectra computed at all
drillings available for this area. Such method is particularly suitable in urban areas where the nature of the outcropping
geological units is masked by city growth and anthropic intervention on the surface geology. The microtremor H/V spectral
ratios evaluated at soft sites located within the downtown profile tend to be smaller than that usually reported in the literature
for such soils. A tendency for amplifications to peaks near 2 Hz is observed only in some sites located on recent alluvial
deposits. Evidences for amplifications of site effects (frequency range 4–8 Hz) were observed in the sampling sites located
on the fault, with a rapid decrease of spectral amplitude just a few tenths of metres away from the discontinuity. Numerical
simulations evidenced the importance of geolithological features at depth levels even greater than 20–30 m. Besides this,
the results strongly confirm the importance of the subsurface geological conditions, in the estimate of seismic hazard at
urban scale. 相似文献
66.
Poverty, vulnerability and the impact of flooding
in the Limpopo Province, South Africa 总被引:1,自引:0,他引:1
The article evaluates household vulnerability after the 2000 flood in two poor communities of the Limpopo Province, South
Africa. The study analyses the forms of vulnerability which disasters such as floods present. Using data gathered from a survey
of households, the study presents the impacts, coping and adapting strategies of households after the 2000 flood. The article
argues that beyond the concern over socio-economic circumstances as the major determinant of household vulnerability, the
management of the disaster can serve to perpetuate vulnerability. 相似文献
67.
Assessment of sand encroachment in Kuwait using Geographical Information System (GIS) technology has been formulated as a
Multi-Criteria Decision Making problem. The Delphi method and Analytical Hierarchy Process were adopted as evaluating techniques,
in which experts’ judgments were analyzed for objectively estimating and weighting control factors. Seven triggering factors,
depicted in the form of maps, were identified and ordered according to their priority. These factors are (1) wind energy;
(2) surface sediment; (3) vegetation density; (4) land use; (5) drainage density; (6) topographic change and (7) vegetation
type. The factor maps were digitized, converted to raster data and overlaid to determine their possible spatial relationships.
Applying a susceptibility model, a map of sand encroachment susceptibility in Kuwait was developed. The map showed that the
areas of very high and high sand encroachment susceptibility are located within the main corridor of sand pathway that coincides
with the northwesterly dominant wind direction. 相似文献
68.
Planning for source water protection in Ontario 总被引:2,自引:0,他引:2
Ontario began developing a drinking water source protection planning process in 2000, after a rural community's water supply was contaminated by pathogens from agricultural runoff. An expert committee report has recommended legislating a new source protection “sphere of jurisdiction” for municipalities; however, no specific new municipal tools or authorities have been proposed as yet. This paper reports findings from an evaluation of the extent to which existing institutional arrangements for land use planning and water management facilitate or constrain source protection by municipalities. A case study of the Regional Municipality of Waterloo suggests there is the potential to link land use planning more strongly to water management through creative use of existing tools, forgoing the need for major institutional changes. 相似文献
69.
Libby Porter 《The Australian geographer》2006,37(3):355-374
Aboriginal cultural heritage protection, and the legislative regimes that underpin it, constitute important mechanisms for Aboriginal people to assert their rights and responsibilities. This is especially so in Victoria, where legislation vests wide-ranging powers and control of cultural heritage with Aboriginal communities. However, the politics of cultural heritage, including its institutionalisation as a scientific body of knowledge within the state, can also result in a powerful limiting of Aboriginal rights and responsibilities. This paper examines the politics of cultural heritage through a case study of a small forest in north-west Victoria. Here, a dispute about logging has pivoted around differing conceptualisations of Aboriginal cultural heritage values and their management. Cultural heritage, in this case, is both a powerful tool for the assertion of Aboriginal rights and interests, but simultaneously a set of boundaries within which the state operates to limit and manage the challenge those assertions pose. The paper will argue that Aboriginal cultural heritage is a politically contested and shifting domain structured around Aboriginal law and politics, Australian statute and the legacy of colonial history. 相似文献
70.
Lionel F. Villarroel Jerry R. Miller Paul J. Lechler Dru Germanoski 《Environmental Geology》2006,51(2):283-299
An intense, but localized rainfall event in February 2003, led to the severe erosion and failure of a tailings disposal impoundment at the Abarόa Antimony Mine in southern Bolivia. The failure released approximately 5,500 m3 of contaminated tailings into the Rio Chilco-Rio Tupiza drainage system. The impacts of the event on sediment quality are examined and compared to contamination resulting from historic mining operations in the headwaters of the basin. Of primary concern are contaminated floodplain soils located along downstream reaches of the Rio Tupiza which were found to contain lead (Pb), zinc (Zn), and antimony (Sb) concentrations that locally exceed Canadian, German, and Dutch guidelines for agricultural use. Spatial patterns in sediment-borne trace metal concentrations, combined with Pb isotopic data, indicate that Pb, Zn, and Sb are derived from three tributary basins draining the Abarόa, Chilcobija, and Tatasi-Portugalete mining districts. Downstream of each tributary, geographical patterns in trace metal concentrations reflect local geomorphic changes throughout the drainage system. Trace metal concentrations within the Rio Chilco decrease rapidly downstream as a result of dilution by uncontaminated sediments and storage of metal enriched particles (e.g., sulfide minerals) in the channel bed as a result of ongoing aggradation. Storage in the floodplains is limited. These processes significantly reduced the dispersal and, thus, the relative environmental affects of tailings eroded from the Abarόa Mine during the 2003 flood. In contrast, storage of Pb, Zn, and Sb in floodplains along the Rio Tupiza is significant, the majority of which is derived from historic mining operations, particularly mining within the Tatasi-Portugalete district. 相似文献