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Abstract. This study implements and tests a mathematical programming model to estimate interregional, interindustry transaction flows in a national system of economic regions based on an interregional accounting framework and initial information of interregional shipments. A national input–output (IO) table, regional data on gross output, value‐added, exports, imports, and final demand at sector level are used as inputs to generate an interregional IO account that reconciles regional economic statistics and interregional transaction data. The model is tested using data from a multiregional global IO database and shows remarkable capacity to discover true interregional trade patterns from highly distorted initial estimates. 相似文献
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Abstract This study examines the indirect effects of military installations on county–level private employment, and specifically the special cases of base closure under the Base Realignment and Closure (BRAC) proceedings of 1988, 1991, 1993, and 1995. Local employment impacts are considered within a partial adjustment construct of the changes model, a specification that facilitates the decomposition of defense personnel changes into their positive, negative, and BRAC–related components. The latter two components are subsequently examined for asymmetric effects attributable to ordinary force drawdown on the one hand, and base closure on the other. Also considered are the specific effects of direct federal assistance as well as facilities conversion and reutilization within BRAC communities. 相似文献
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Kerlijne Romanus Jan Baeten Jeroen Poblome Sabina Accardo Patrick Degryse Pierre Jacobs Dirk De Vos Marc Waelkens 《Journal of archaeological science》2009
Pitch compounds are frequently identified inside archaeological ceramic vessels. As their presence might affect the permeation of oil or wine into the ceramic fabric, experiments were conducted in which the diffusion of lipids or polyphenols into pitched and non-pitched modern vessels was followed by chemical analysis. Results show that the polyphenols of wine can intrude into the ceramics even through a pitch layer. Consequently, the absence of polyphenols in archaeological sherds is not due to their inability to reach the ceramic matrix under the pitch layer. By contrast, a pitch layer is quite effective to avoid oil intrusion into the ceramic matrix. Thus, it seems logical that oil amphorae would have been coated with pitch at the inside prior to use. Experiments in which the pitched ceramic was simultaneously exposed to oil and wine, show that the wine makes the pitch more permeable for the lipid compounds. These experimental data are confronted with residue analysis results obtained on amphorae fragments excavated in Sagalassos, Turkey. Pitch and oil were frequently found together. Based on a polyphenol test, indications for wine storage could only be obtained for two vessels. Against this background, the possible uses of the Sagalassos amphorae are discussed, and the traditional association of pine pitch with wine storage in archaeological amphorae is critically assessed. 相似文献
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Thegn N. Ladefoged Patrick V. Kirch Samuel M. Gon III Oliver A. Chadwick Anthony S. Hartshorn Peter M. Vitousek 《Journal of archaeological science》2009,36(10):2374-2383
Intensive agricultural systems interact strongly and reciprocally with features of the lands they occupy, and with features of the societies that they support. We modeled the distribution of two forms of pre-European contact intensive agriculture – irrigated pondfields and rain-fed dryland systems – across the Hawaiian archipelago using a GIS approach based on climate, hydrology, topography, substrate age, and soil fertility. Model results closely match the archaeological evidence in defined locations. On a broader scale, we calculate that the youngest island, Hawai'i, could have supported 572 km2 of intensive agriculture, 97% as rain-fed dryland field systems, while Kaua'i, the oldest island, could have supported 58 km2, all as irrigated wetland systems. Irrigated systems have higher, more reliable yields and lower labor requirements than rain-fed dryland systems, so the total potential yield from Kaua'i (49k metric tons) was almost half that of Hawai'i (97k metric tons), although Kaua'i systems required only 0.05 of the agricultural labor (8400 workers, versus 165,000 on Hawai'i) to produce the crops. We conclude that environmental constraints to intensive agriculture across the archipelago created asymmetric production efficiencies, and therefore varying potentials for agricultural surplus. The implications both for the emergence of complex sociopolitical formations and for anthropogenic transformation of Hawaiian ecosystems are substantial. 相似文献
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Gang Meng G. Brent Hall Mary E. Thompson Patrick Seliske 《The Canadian geographer》2013,57(2):154-172
This study assesses the overall spatial variations and neighbourhood‐level “hot spots” of low birth weight and preterm birth incidence within three public health units in Ontario, Canada. The analysis uses a stepwise approach of intra‐class correlation analysis, a spatial scan statistic, and multilevel spatial modeling. Results show that neighbourhood level variation accounts for only 2–3 percent of the total variation of adverse birth outcomes in the study area. However, strong spatial autocorrelation is observed at the neighbourhood level, and spatial clusters of relatively high adverse birth outcome rates exist in areas that are associated with environmental risks, including pollution sources and proximity to highways. Thus, although estimated neighbourhood impacts on adverse birth outcomes are small compared with those of individual‐level risks, local high potential environmental risk areas are identifiable. Environmental surveillance and spatial statistical analysis should be conducted regularly by local health authorities to identify and monitor the impact of environmental changes on health in general and on birth outcomes in particular. Specific community‐oriented health interventions may be required to reduce observed local health impacts. 相似文献
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Patrick Ryan 《Folklore》2013,124(3):313-328
This paper looks at the self-representation of contemporary or revival storytellers claiming “Celtic” identity for themselves as storytellers, largely based on imagined traits of generic “Celtic” storytellers and storytelling styles, and content, which are conveyed via commercial images, suppositions about the Romantic era, and other mediated, second-hand or even erroneous sources. At the same time, such representations are compared with the self-representations of three traditional storytellers from Ireland and Scotland. 相似文献
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Else Kragelund Holt 《SJOT: Scandinavian Journal of the Old Testament》2013,27(1):87-103
Abstract Die Wörter in Deut 26,5 werden in der Pæsach Haggada transitiv verstanden. Für unsere gewöhnliche intransitive Lesung gibt es keine klaren Belege vor der Zeit Ibn Ezras. Es ist schwierig, eìne Situation in der Geschichte Israels zu finden, wo die intransitive Lesung verständlich ist Hier prüfe ich, das Problem umzukehren. Von der Hypothese ausgehend, daß die transitive Lesung die primäre ist suche ich die Voraussetzungen für die Entstehung der intransitiven Lesung. 相似文献