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31.
Even as the world’s sole superpower, the United States requires the cooperation of other states to achieve many of its foreign policy objectives. The President of the United States thus often serves as ‘Diplomat in Chief’ in public diplomacy efforts to appeal directly to publics abroad. Given Donald Trump’s antagonistic approach to foreign relations and widespread lack of popularity, what are the implications for support for US policy among publics abroad – particularly among middle power states allied to the US? While previous research on public opinion relying on observational data has found that confidence in the US President is linked to support for American foreign policy goals, the mechanisms at work remain unclear. Using original data from survey-based experiments conducted in Canada and Australia, this article seeks to clarify the effect of ‘presidential framing’ (presenting a policy goal as endorsed or not endorsed by Trump) on attitudes toward key policy issues in the Canada–US and Australia–US relationships. Results point to a negative ‘Trump framing’ effect in Canadians’ and Australians’ trade policy attitudes, but such an effect is not observed in other policy domains (energy policy in Canada, and refugee policy in Australia).  相似文献   
32.
Between 1950 and 1990, housing was the driving force behind the spatial growth of the Randstad. Growth poles (1970s) and later VINEX locations (1990–2010) were the main components of growth management. Transport infrastructure has developed greatly since the 1920s. Since 1990, infrastructure development has increasingly become the structuring force for the spatial dynamics of the Randstad. Schiphol was seen as the mainport for airlines, and Rotterdam-Europoort as the mainport for shipping lines and container transport. The landside infrastructural connections for Schiphol and Europoort had a big impact on the growth in the capacity of continental roads and rail lines. ICT- and energy infrastructure are now developing quickly. Recently, Amsterdam Internet Exchange became the largest ICT node in Europe. Finally, the Delta programme was introduced, strengthening the coastal areas and leaving more room for the rivers. For the future, a combination of housing, infrastructure and water for spatial developments will determine the spatial structure of the Randstad further. A compartmentalized plan of the Randstad between the main dikes is presented, which will increase the resilience of functions of the Randstad in the future when the North Sea level is expected to rise substantially. The analysis presented could be relevant for many urban deltas worldwide.  相似文献   
33.
目前天津经济技术开发区(TEDA)已发展成为天津大都市区的新兴边缘城市。本文以居民问卷调查的第一手资料为基础,分析天津大都市区内各地区居民对TEDA的认知程度与迁居意向以及地域选择性特征,为以TEDA为核心的人口反磁力中心建设为主导的天津大都市区人口调整对策提供科学依据。  相似文献   
34.
An earthquake of magnitude 6.2 (M b ) occurred in west-central part of Colombia on January 25, 1999. This earthquake is officially called Quindio Earthquake from the name of the most affected province. The earthquake caused disastrous damage to a large number of buildings resulting in significant casualties. In Armenia City and its neighbouring villages close to the epicentre over 1000 people were killed by the earthquake and the total monetary loss reached US$ 2 billion. Armenia City, which has an approximate population of 280 000 people, apparently suffered the worst in terms of casualties and damage to the buildings.

The present paper focuses on the causes of damage to houses and buildings in Armenia City. First, the evolution of the urban area of the city was investigated using historical features available maps from each era. Then a correlation between buildings damage and topographical features of the city was studied. The effects of geological features and amplification of ground motion were also investigated.  相似文献   
35.
On October 31 and November 1, 2002, two earthquakes of magnitude 5.4 and 5.3 hit the area at the border between the Molise and Puglia regions in Southern Italy. The damage pattern in the epicentral area qualified the quake as an intensity VII MCS event, although providing a notable exception relevant to the small village of San Giuliano di Puglia. Since the first macroseismic survey, it appeared clear that in S. Giuliano the intensity was two degrees higher with respect to three neighbouring villages located within a radius of 3 km. Soon after the quake, our team started a campaign of microtremor HVSR measurements (Horizontal to Vertical Spectral Ratio), then we installed accelerometers and carried out damage and geological surveys. Finally, we performed a geoelectrical tomography and two profiles of Vs velocity with depth using the NASW technique (Noise Analysis of Surface Waves). The preliminary observations indicate that ground motion amplification is present in S. Giuliano within the frequency band that may affect building. A strong velocity contrast 20 m deep causes the predominant peak. More amplification could be due to more complicated, 2D effects. As regards the damage pattern, it divides S. Giuliano in three zones showing different characteristics and seismic behaviour. A building-by-building survey is still under way to better evaluate vulnerability variations in different zones of the village. However, the acquired data so far is sufficient to propose site amplification as a possible cause of the damage enhancement observed in S. Giuliano.  相似文献   
36.
Acceleration data from local and regional earthquakes is of prime importance in evaluating the seismic hazard. Consequently, strong motion accelerometers are currently installed at more than 60 locations in Israel. We have explored the possibility of site amplification effects at 10 sites where local earthquakes triggered strong motion accelerometers by integrating empirical and analytical estimations. Implementing H/V spectral ratio techniques using 15 accelerograms from nine earthquakes, 105 seismograms shear-wave records of 35 local and regional earthquakes and seismograms of microtremors were used in the empirical evaluations. The subsurface models were constructed by integrating available geological and geophysical information at the analysed site with empirically evaluated site response functions. Amplification effects of factor 3-6 are observed at various frequencies in the 0.8-6.0 Hz band. Through the analysis process it became evident that the instant availability of many useful time windows of microtremors provides systematic estimations of the fundamental resonance frequency of each site and their associated amplification levels, which are similar to those obtained from H/V spectral ratios of seismograms and accelerograms and to those inferred from the subsurface geology. Analytical transfer functions should be reviewed with respect to empirical site response evaluations. Estimations that are based on only one approach may be totally misleading.  相似文献   
37.
Abstract

A non-parametric multidimensional regression method is proposed for the prediction of seismic ground motion parameters. The main features which distinguish the method from standard regression procedures are: (1) The relationship between the input and output variables is not selected a priori by a prediction law, (2) an arbitrary number of input variables Can be taken into account, provided that an appropriate data base exists, and (3) the computational procedure is very simple. The results can be easily updated when new information becomes available. The method has been applied for the derivation of attenuation relations by using a combination of databases compiled by other researchers. In the majority of the cases discussed in this paper, the method was used for the prediction of horizontal peak ground acceleration as a function of magnitude and distance. In some cases, ground conditions were also taken into account. Some results on the attenuation relations of peak ground velocity and displacement, as well as Arias intensity, are also presented.  相似文献   
38.
Stable nitrogen isotopes have been used to reconstruct infant feeding practices as nursing infants have elevated δ15N ratios compared with their mothers. However, infancy is also a time of rapid growth, which may alter nitrogen isotope diet‐to‐tissue spacing. Several studies have documented a decrease in δ15N during growth in tissues with relatively fast accretion rates. This study investigates the effect that the growth of long bones, via collagen accretion, has on δ15N ratios. Long bones from individuals aged seven to nineteen years were obtained from a protohistoric ossuary in Ontario, Canada. Analysis of juveniles and adolescents permitted the examination of growth in a group who were not also nursing. It is concluded that a nitrogen isotope growth effect is not detectable in bone collagen from juveniles and adolescents, because: (1) δ15N ratios are not significantly different among the epiphyses, metaphyses and diaphysis of a growing long bone; (2) δ15N ratios are not significantly different between faster‐growing versus slower‐growing metaphyses; and (3) δ15N ratios are not significantly different between bones (or areas of a bone) that are still undergoing growth, versus bones that have ceased growing. The relatively slow speed of collagen accretion may explain why a growth effect is not manifested. Ultimately this research lends support to the use of nitrogen isotopes from bone collagen for infant feeding reconstructions. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
39.
Dating of fired clay ceramics can be critical in building chronologies of archaeological sites. However, direct dating techniques such as luminescence, archaeomagnetism and radiocarbon dating are not always suitable or even possible. Rehydroxylation dating of fired clays is a developing method that has the potential to provide an alternative/complementary approach. Determination of a second stage, Stage II, mass gain rate in fired/reheated clay ceramics using a time1/4-based model is central to this method. Experiments on modern brick samples demonstrate that the Stage II mass gain is not linear with t1/4 as expected. The non-linearity observed can be taken account of through the introduction of a time-offset that represents the additional time required for mass gain at a specific aging temperature to equate to the additional mass gained above this aging temperature during cooling of the sample post-firing/reheating. Simulations of the mass gain curves expected during post-firing/reheating cooling highlight the significant effect of this mass gained during cooling and provide excellent agreement with experiment. Simulations also suggest that the two-stage structure in the mass gain curves observed might be better explained as largely the result of a single t1/4-based process (Arrhenius in temperature dependence) across both stages; Stage I results from mass gained during cooling with Stage II resulting from mass gained during static temperature conditions. The overall implications for the dating method are that a non-linear Stage II mass gain (as a function of time1/4) is expected and that an improved time-offset model provides a solution while removing issues of subjectivity in isolating the Stage II mass gain rate. This should lead to an improvement in the accuracy of RHX dates produced on archaeological material and further its development as a viable dating technique.  相似文献   
40.
韩晓旭  孙威  樊杰 《人文地理》2011,26(4):17-22
空间布局规划后评价的研究与实践日益受到学术界和政府部门的关注。首先,在界定空间布局规划后评价基本概念的基础上,简要回顾了空间布局规划后评价的发展历程。其次,从评价对象、评价标准、评价内容三个方面对国内外空间布局规划后评价的相关研究成果进行了系统梳理和总结。最后,从时间安排、研究重点两个方面对我国空间布局规划后评价的发展进行了思考与展望。  相似文献   
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