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41.
As deportations from the United States rose to unprecedented levels, a nationwide immigration enforcement program Secure Communities helped identify deportable noncitizens under arrest in county jails. Examining county‐level variation in deportation activity between 2008 and 2013, this paper contributes to immigration policy research by examining how county officials in some locations facilitated exceptionally restrictive deportation outcomes while others exercised the discretion to turn noncitizens over for deportation sparingly. Consistent with a hypothesized “tiered influence” relationship, but contrary to a “racial threat” hypothesis, Hispanic concentration predicts the highest levels of exercised discretion where Hispanic concentration is neither too small nor too large. Noncitizens under arrest seem to have benefited from above‐average Hispanic concentrations, except in counties where Hispanics exceed about 40 percent of the population.  相似文献   
42.
This article discusses the application of new technologies, software coding and computer analysis in the social sciences and humanities, mainly in the field of economic history. In the last two decades, the use of new computer technologies among historians to develop theories and solve questions has fostered a vibrant historiographical debate. However, these new digital tools have largely been used as an end in themselves, rather than as a means to develop hypotheses and answer questions. This has prevented researchers from fully exploiting such technologies in their field. In this article, I discuss how I designed a new multi-relational database using the “Access” package and SQL language to test the “industrious revolution” hypothesis and present the “vicarious consumption” theory as an alternative model for analyzing the eighteenth-century circulation of Chinese goods in the Western Mediterranean region. It presents the cross-referencing method I used to analyze the historical information I collected, mainly from probate inventories and trade records. This method makes it possible to navigate through the data in a way that goes beyond the traditional use of “excel” tables.  相似文献   
43.
44.
In order to assess further the recent claims of ∼3.4 Ma butchery marks on two fossil bones from the site of Dikika (Ethiopia), we broadened the actualistic-interpretive zooarchaeological framework by conducting butchery experiments that utilized naïve butchers and rocks unmodified by human flaking to deflesh chicken and sheep long limb bones. It is claimed that the purported Dikika cut marks present their unexpectedly atypical morphologies because they were produced by early hominins utilizing just such rocks. The composition of the cut mark sample produced in our experiments is quite dissimilar to the sample of linear bone surface modifications preserved on the Dikika fossils. This finding substantiates and expands our earlier conclusion that—considering the morphologies and patterns of the Dikika bone surface modifications and the inferred coarse-grained depositional context of the fossils on which they occur—the Dikika bone damage was caused incidentally by the movement of the fossils on and/or within their depositional substrate(s), and not by early hominin butchery. Thus, contrary to initial claims, the Dikika evidence does not warrant a major shift in our understanding of early hominin behavioral evolution with regard to carcass foraging and meat-eating.  相似文献   
45.
During the long-lasting cultural sequences of the Shurābeh and Sialk archeological mounds (6200–550 BC) the inhabitants encountered numerous diversified crises along a narrow fertile passageway at the edge of the Central Iranian Plateau Great Desert. Some of the threats may be attributed to earthquakes, drastic climatic changes, and man-made environmental deterioration, which possibly led to the settlement withdrawing at different stages toward a more suitable location. Our study identified the occurrence of a large-magnitude earthquake around 3800 BC along the Kāshān fault, which is well-documented by various lines of circumstantial evidence, including: (i) numerous contemporaneous smashed skeletons and artifacts underneath collapsed walls and ceiling debris in several different areas; (ii) tilted and collapsed walls; (iii) nearly N–S oriented fallen large storage jars; and (iv) nearly vertical deep ground fractures cutting walls and floors of the Sialk III5 South Mound settlement. Archeological data also shows additional stratigraphic discontinuities and damages that may be attributed to earthquakes. However, damage features in limited exposed trenches are less conclusive and require additional careful excavations. Apparent ancient paleo-architectural innovative attempts to enhance the coherency/elasticity of the structures and minimize earthquake damage to buildings were also noted, suggesting the indigenous earthquake hazard mitigation endeavor. There seems to be a correlation between some site abandonment dates and possible drastic regional draught/cooling events. The natural and anthropogenic impacts addressed in this study constituted major threats to the sensitive archeological settlements at the fringe of the desert and the vicinity of the Kāshān active fault since antiquity.  相似文献   
46.
Regional Externalities And Growth: Evidence From European Regions*   总被引:1,自引:0,他引:1  
Abstract. This paper models externalities of production across regional economies. Under the assumption that knowledge diffuses without political or administrative barriers, we derive externalities that affect the steady state and the process of growth of each economy. The empirical counterpart of the reduced form equation summarizing the process of growth allows us to test for the presence of regional spillovers and to measure their magnitude. Our results for a sample of European regions show that spillovers are far from negligible, are robust to the consideration of variables within each region, and may cause nondecreasing returns at the spatial aggregate level. The paper also relates previous empirical evidence on spatial dependence in growth studies to the externalities modeled here.  相似文献   
47.
Behavioural issues are a main focus of current Palaeolithic research, especially where the archaeological record of archaic hominids is concerned. Often these issues are approached using archaeological assemblages that are palimpsests defined exclusively by stratigraphic criteria. The aim of this paper is to discuss whether such assemblages are adequate for solving behavioural questions. As a case study, we will present the lithic provisioning strategies documented in level L of the Abric Romaní Middle Palaeolithic site. The results of this study suggest that the number of events and/or the amount of time included in the archaeological assemblages could be relevant when explaining the interassemblage variability, given that palimpsests tend to reduce the behavioural variability. If we want to approach the behavioural domain, we need archaeological assemblages of higher temporal resolution, defined through the identification of single activity events.  相似文献   
48.
The colluvial soils of Galicia (NW Spain) are records of Holocene environmental change. In spite of the omnipresence of charcoal fragments in these soils, the effect of fires on the development of the Galician landscape and the potential role of past societies are poorly understood.  相似文献   
49.
While the excavation of individual sites remains fundamental to the creation of the Palaeolithic archeological record, increasingly the focus of prehistoric research is on human adaptations to and within natural regions. Such a reorientation implies viewing sites and occupations as samples of different suites of activities in various habitats across space and time; it is dependent on the use of radiocarbon to date and relate occupation residues among sites; and it necessitates the application of methods to uncover patterns of human mobility as an integral aspect of subsistence economy, demographic arrangements and social relations. This paper contributes to the regional study of Last Glacial foragers by presenting preliminary aspects of a case study from the Asón River basin in eastern Cantabria. Assembled here are data from several recent and a few older excavations in sites distributed between the present shore of the Bay of Biscay and the uplands of the Cantabrian Cordillera. The main sites are El Otero, La Chora, La Fragua and El Perro near or at the present mouth of the river, the classic cave of El Valle in the mid-valley, and El Mirón and El Horno near the cave art loci of Covalanas, La Haza and Cullalvera in the upper valley. While the highest density of known sites in the whole drainage area occurs during the Magdalenian and Azilian periods (17–10 kya), there is evidence for substantial abandonment of the montane interior during the Mesolithic, when human settlement was concentrated around the estuary of the Asón, after which time the whole valley was repopulated in the Neolithic.  相似文献   
50.
The study of public policy deals with subsystems in which actors cooperate or compete to turn their beliefs into policy solutions. Yet, most studies concern mature subsystems in which the main actors and their allies and enemies can easily be identified. This paper tackles the challenge of studying nascent subsystems, in which actors have begun to engage in politics but are uncertain about other actors’ beliefs. Actors therefore find it relatively difficult to identify their allies and opponents. Focusing on the Advocacy Coalition Framework, we examine three main ways in which actors might agree to support the same policy design before they decide whether or not to form long‐term relationships within advocacy coalitions: they see the issue through the same lenses, they follow leaders, or they know each other from earlier cooperation. We use the case of fracking policy in Switzerland and the UK as a key example, in which actors have begun to agree with each other, but where final policy outputs were not yet defined, and long‐term relationships not yet observable. We find that, when dealing with new issues, actors strongly rely on former contacts rather than shared ideologies or leadership.  相似文献   
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