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991.
We analyze whether efficiency wages operate in urban labor markets, within the framework proposed by Ross and Zenou, in which shirking at work and leisure are assumed to be substitutes. We use unique data from the American Time Use Survey (ATUS) that allow us to analyze the relationships between leisure, shirking, commuting, employment, and earnings. We confirm that shirking and leisure are substitutes, and present an estimate of this relationship, representing the only empirical test of the relationship between a worker's time endowment and shirking at work. Our findings point to the existence of efficiency wages in labor markets.  相似文献   
992.
Pigments appearing on ninth–twelfth-century AD-carved stucco, wall painting, and terracotta friezes excavated at Nishapur in north-eastern Iran were investigated by optical reflectance spectroscopy, micro X-ray fluorescence spectrometry (μ-XRF), X-ray diffractometry (XRD), micro-Raman spectroscopy (μ-Raman), and scanning electron microscopy (SEM). Many of the pigments identified including vermilion, red lead, hematite, limonite, carbon black, atacamite, calcite, and gypsum have been identified in previous studies of pigments used in later Islamic periods. However, a series of unusual pigments such as wulfenite, pyromorphite, phoenicochroite, and jarosite were also found in the present study. The association of kaolinite and alunite with limonite and other Fe-bearing yellow pigments points to a local provenance for these pigments. In addition, the presence of orpiment in the vermilion may be indicative that the vermilion was artificially manufactured. These findings suggest that pigment use and manufacturing during the ninth to eleventh centuries in Nishapur was still in a trial-and-error stage and the palette known from the twelfth century onwards had not yet been systematized.  相似文献   
993.
Traditional taphonomic analyses do not consider the emergent properties resulting from the relationship of variables. Several of these emergent properties are expressed spatially. Here, we present a spatial taphonomic approach to the understanding of post-depositional processes affecting experimental assemblages modified by fluvial currents. Spatial statistical methods are a great tool to understand how different taphonomic variables relate at a spatial scale. The results of the application of this method to bone assemblages affected by low- and high-energy flows show the loss or modification of most of the original spatial taphonomic relationships. It also shows the degree of bone loss according to element, anatomical section and bone structure, and shape types. Anisotropy is identified in both experimental contexts. These results add new criteria to assess the impact of water flows in bone assemblages and contribute to define the properties of lag assemblages.  相似文献   
994.
Compound-specific amino acid carbon-isotope compositions have shown particular promise for elucidating dietary behaviors in complex environmental contexts, and may also be able to mitigate the effect of many of the limitations inherent to palaeodietary reconstructions. Here, we investigate the efficacy of compound-specific amino acid isotopic proxies in characterizing the consumption of different dietary protein sources using amino acid carbon-isotope compositions for humans and fauna from Rössberga (Early to Middle Neolithic), Köpingsvik (Mesolithic and Middle Neolithic), and Visby (Medieval Period), Sweden. We also assess the explanatory capabilities of an isotopic mixing model when used with essential amino acid carbon-isotope compositions of humans and local fauna. All three isotopic proxies distinguished among humans from the three sites consistently and informatively, and were able to enhance the broad interpretations made using bulk isotopic compositions. The mixing model palaeodietary reconstruction revealed considerable diversity in relative protein source contributions among individuals at both Köpingsvik and Visby. Comparing the mixing model for bulk carbon- and nitrogen-isotope compositions to the model for essential amino acid isotopic compositions further demonstrated the likelihood of underestimation and overestimation of marine protein consumption for both aquatic-dominant and mixed marine-terrestrial diets when using bulk isotopic compositions.  相似文献   
995.
This paper examines an alternative approach to previously proposed models of prehistoric exchange such as the law of monotonic decrement or the down-the-line exchange model developed by Renfrew (Proceedings of the Prehistoric Society 34: 319–331, 1968, Renfrew 1977) to explain the distribution of obsidian across the Near East during the Neolithic period. Renfrew’s down-the-line model, which results in a very regular and clustered network, does not permit the circulation of obsidian to regions of the Near East that are further than 300 km from the source zones, as is shown in the archaeological data available. Obsidian exchange is a complex system where multiple factors interact and evolve in time and space. We therefore explore Agent-Based Modelling (ABM) so as to get a better understanding of complex networks. ABM simulations of an exchange network where some agents (villages) are allowed to attain long-distance exchange partners through correlated random walks are carried out. These simulations show what variables (population density, degree of collaboration between villages…) are relevant for the transfer of obsidian over long distances. Moreover, they show that a type of small-world exchange network could explain the breadth of obsidian distribution (up to 800 km from source) during the Near Eastern Neolithic.  相似文献   
996.
Abstract

The last material evidence of the former Palace of Brussels, the Coudenberg archaeological site, is situated at the heart of the city, constitutes a remarkable part of its heritage, and has been listed as a legally protected monument. Following the redevelopment of the Royal Quarter in the eighteenth century, the successive archaeological discoveries of the last twenty-five years, and the progressive growth of the areas accessible to the public, the various components of the site have not all been preserved in the same condition. The work involved in developing such a complex has already necessitated considerable resources, and still requires more today. The owners, the City of Brussels and the Brussels-Capital Region, as well as the site’s managers, the not-for-profit association ‘Palais de Charles Quint’, are continuing their programme of developing, promoting, and preserving the remains in order to hand down this important historical evidence to future generations.  相似文献   
997.
998.
Abstract

The objective of this article is to determine the number of combatants in the Mixtón War (1541–42), one of the most important military confrontations of the early years of the vice-royalty in Western Mexico, by analysing the Peñol de Nochistlán. To this end, information provided by historians has been compared with the population estimates established from the density of settlements known from archaeological evidence in order to define the area occupied by the armies involved in the conflict. This exercise resulted in a shifting array of spaces that could have been used by the combatants during confrontations. However, it will enable more intense archaeological prospecting in the area around the site of El Tuiche — the place identified as the Peñol of Nochistlán — revealing new evidence of the events that occurred on this battlefield.  相似文献   
999.
The aim of this paper is to identify the determinants of the geographical mobility of skilled individuals, such as inventors, across European regions. Among a large number of variables, we focus on the role of social proximity between inventors’ communities. We use a control function approach to address the endogenous nature of networks, and zero‐inflated negative binomial models to accommodate our estimations to the count nature of the dependent variable and the high number of zeros it contains. Our results highlight the importance of physical proximity, job opportunities, social networks, as well as other relational variables in mediating this phenomenon.  相似文献   
1000.
The Augustan Roman temple at Barcino has been a key element during the last 60 years in the research of the colony's urban development. Its peculiar elongated and narrow plan, first proposed in 1835, and its location at the highest point of the ancient city have dictated our understanding of the urban layout of Barcino by conditioning the shape of the city's forum and affecting the interpretation of the archaeological excavations carried out in the area since then. This paper proposes an alternative plan of the temple, based on data drawn from recent archaeological excavations, topographical analysis, typological comparisons, and the study of written sources. Our alternative hypothesis for the temple permits an in‐depth reinterpretation of the plan of the forum and the evolution of the urban plan.  相似文献   
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