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991.
992.
M. S. Tite 《Journal of Archaeological Method and Theory》1999,6(3):181-233
The study of the life cycle of pottery, from the selection of raw materials and the production stage through distribution and use to ultimate discard, can make a valuable contribution to archaeological research. The aim of the present paper is to provide a summary and critical assessment of the particular contribution of the physical sciences to the reconstruction and interpretation of this life cycle, in large part through the presentation of selected case studies. The topics covered include the reconstruction of the technology used in pottery production, through a combination of microscopy, radiography, and chemical analysis; the investigation of the extent of craft specialization and the organization of pottery production; the reconstruction of pottery distribution from its production center, using thin-section petrography and chemical analysis, and the interpretation of these data in terms of exchange and trade; the reconstruction of the consumption stage or uses to which pottery was put, from the study of surface wear, organic residues, and performance characteristics; and a discussion of the reasons for the introduction of pottery and for the different technological choices made in pottery production. Throughout, the importance of considering the overall environmental, technological, economic, sociopolitical, cultural–ideological and historical context in which the pottery was produced, distributed, and consumed is emphasized. The paper is concerned, almost-exclusively, with unglazed earthenware spanning prehistory through to circa 1500 AD. 相似文献
993.
994.
Jinmium rock shelter is famous for the claims made by Fullagar et al. (1996) for the early human colonization and ancient rock art of northern Australia. These claims were based on thermo-luminescence ages obtained for the artefact-bearing quartz sediments that form the floor deposit at the site. In this paper, we outline the background to the optical dating programme at Jinmium, and describe the experimental design and statistical methods used to obtain optical ages from single grains of quartz sand. The results, interpretations, and implications of this dating programme are reported in a companion paper (Roberts et al. 7999, this volume). 相似文献
995.
996.
In this article it is argued that conventional agro-ecological and organizational concepts used in pastoral development are strongly biased towards the formulation and enforcement of norms. This leads development experts to attempts to control pastoralists and their herds. The policies and development interventions based on these assumptions have been largely unsuccessful. As a consequence attention for dryland areas and pastoral development has declined among researchers and development agencies. An important reason for this failure is the fundamental misfit between these normative concepts and the reality of dryland ecosystems and pastoral society. In order to show this, an alternative view on rangeland ecology and pastoral society is presented, supported by a case study of Fulbe pastoral society in dryland Central Mali. The authors argue that approaches to pastoral development must be revised in the direction of the dynamics inherent in the pastoral way of life. 相似文献
997.
Richard L. Francis Timothy J. Lowe Gerard Rushton M. Brenda Rayco 《Geographical analysis》1999,31(1):67-87
When solving a location problem using aggregated units to represent demand, it is well known that the process of aggregation introduces error. Research has focussed on individual components of error, with little work on identifying and controlling total error. We provide a focussed review of some of this literature and suggest a strategy for controlling total error. Consideration of alternative criteria for evaluating aggregation schemes shows that the method selected should be compatible with the objectives of the analyses in which it is used. Experiments are described that show that two different measures of error are related in a nonlinear way to the number of aggregate demand points (q), for any value of the number of facilities (p). We focus on the parameter q/p and show that it is critical for determining the expected severity of the error. Many practical implementations of location algorithms operate within the range of q/p where the rate of change of error with respect to q/p is highest. 相似文献
998.
M.L.R. Smith 《International affairs》1999,75(1):77-97
One of the most enduring ideas about the Northern Ireland conflict is that it has been rigorously studied. This is a myth. The stark absence of analysis of its military and international dimensions makes the conflict one of the least understood of modern times. Scholarly studies of Northern Ireland have been insulated from influences in the wider academic world by the dominance of hitherto unchallenged images about the crisis. These images support a dominant orthodoxy that has confined intellectual investigation of the 'Troubles' to Northern Ireland itself, sustaining a view that little of value can be gained from studying the military nature of the conflict. This orthodoxy is one to which, depressingly, the international relations community has been only too willing to contribute to justify its fear and neglect. Not only does this reflect poorly on academic practice but it has also helped to engender a dangerously distorted image of the conflict that bodes ill for the future. 相似文献
999.
Ralph M. Braid 《Journal of regional science》1999,39(1):125-148
In this paper I examine the profit-maximizing locations of entrants. Suppose that firms practice spatial price discrimination and consumer locations are discrete, such as five equally spaced towns on a roadway. With completely inelastic consumer demand an entrant between two existing firms is often indifferent between the symmetric (central) location and a continuum of asymmetric (noncentral) locations. However, downward-sloping consumer demand often causes the entrant to strictly prefer either of two asymmetric locations to any other location. These results are very different from those found in mill-pricing (free-on-board or f.o.b.-pricing) models. 相似文献
1000.
Frederick M. Hess 《政策研究杂志》1999,27(3):459-473
Amid the torrent of reform activity in urban school systems, some proposals fare better than others. The traditional technocratic presumption is that reforms are chosen for their educational merit. I suggest that, to the contrary, institutional incentives encourage urban policymakers to emphasize symbolic appeal. Data from a 1995 study of 57 urban districts are used to compare the fate of two school reforms. The more symbolically attractive reform was supported, proposed, and enacted much more widely, although neither research nor observer responses suggested its superiority. 相似文献