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This paper presents an analysis of networks among small and medium-sized enterprises in the Irish biotech sector. The study applies social network analysis to determine the structure of networks of company directors and inventors in the biotech sector. In addition, on the basis of interviews, this article analyses the extent of actual knowledge flow through these industry networks. The paper makes both a theoretical and methodological contribution to innovation network research. In relation to theory, the findings of the social network analysis indicate that the extent and path of knowledge flow are influenced by both the type of knowledge in question and whether the network is of a formal or informal nature. Methodologically, the results of this paper raise questions about the application of social network analysis in innovation studies. 相似文献
123.
John Stachel 《Revue de synthèse / Centre international de synthèse》2005,126(2):353-365
As the sobriquet «Zweistein» suggests, within the theoretical physics community Wolfgang Pauli came to be regarded as second in eminence only to Albert Einstein. Over a period of thirty-five years, they interacted both intellectually and personally. This paper focuses on four interrelated topics of their discussions. 1) The theory of relativity: at the age of twenty, Pauli prepared the definitive survey of relativity, a survey which he revised near the end of his life and which remains invaluable to physicists and historians of physics. 2) Unified field theories: although initially sympathetic to Einstein's search for a unified theory of electromagnetism and gravitation, and having made important contributions to the subject, Pauli came to regard such efforts as fruitless. 3) Foundations of quantum mechanics: Pauli's negative evaluation of Einstein's program grew out of their sharply differing evaluations of the role that quantum mechanics would play in the future, development of theoretical physics. 4) Quantum gravity: Pauli recognized that, until the achievement of a successful reconciliation of quantum mechanics and general relativity — an achievement that still eludes us — Einstein's challenge to quantum mechanics could not be laid to rest. 相似文献
124.
The extent to which North Atlantic Holocene climatic perturbations influenced past human societies is an area of considerable uncertainty and fierce debate. Ireland is ideally placed to help resolve this issue, being occupied for over 9000 yr and located on the eastern Atlantic seaboard, a region dominated by westerly airflow. Irish bog and lake tree populations provide unambiguous evidence of major shifts in surface moisture through the Holocene similar to cycles recorded in the marine realm of the North Atlantic, indicating significant changes in the latitude and intensity of zonal atmospheric circulation across the region. To test for human response to these cycles we summed the probabilities of 465 radiocarbon ages obtained from Irish archaeological contexts and observe enhanced archaeological visibility during periods of sustained wet conditions. These results suggest either increasing density of human populations in key, often defensive locations, and/or the development of subsistence strategies to overcome changing conditions, the latter recently proposed as a significant factor in avoiding societal collapse. Regardless, we demonstrate environmental change is a significantly more important factor in influencing human activity in the landscape than has hitherto been acknowledged. 相似文献
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126.
This paper examines the dynamics of the computer hardware industry in Ireland and Scotland in a global context, from its inception in the late 1950s to the present. It provides a detailed account of plant openings and closures in both the system assembly and the component manufacturing segment. It describes the development of the computer hardware industry from mainframe assembly, through minicomputer assembly to microcomputer assembly and the shift of system assembly and component production activity to the Far East and Eastern Europe since the mid-1990s. The developments are analysed in terms of Schoenberger's (1997) model of concentrated deconcentration in the context of time-based-competition. It is shown that the model, with substantial qualification, fits the developments since the 1980s. 相似文献
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129.
John Kantner 《Journal of Archaeological Research》2008,16(1):37-81
In the 1970s and 1980s, regional analysis was an influential part of archaeological research, providing a discrete set of
geographical tools inspired by a processual epistemological and interpretive perspective. With the advent of new technologies,
new methods, and new paradigms, archaeological research on regional space has undergone significant changes. This article
reviews the state of regional archaeology, beginning with a consideration of its history and a discussion of the fundamental
issues facing regional investigations before focusing on developments over the last several years. On one hand, the diversification
of archaeological theory has created new paradigms for thinking about human relationships with one another and with the physical
environment across regional space; in this regard, historical ecology, landscape archaeology, and evolutionary theory have
been particularly influential in recent years. This has led to a corresponding diversification of the traditional methods
of regional analysis. Most notably, the advent of powerful digital technologies has introduced new tools, especially those
from the geographic information sciences, that build on the quantitative methods of past approaches. The investigation of
regional data is no longer based on a discrete toolkit of simple mathematical and graphical procedures for representing spatial
relationships. Instead, regional archaeology has matured into a diversity of multiscalar spatial and geostatistical techniques
that inform many areas of archaeological inquiry. 相似文献
130.
Yaroslav V. Kuzmin 《Journal of Archaeological Research》2008,16(2):163-221
This article focuses on the presence of humans in Siberia and the Russian Far East at the coldest time of the Late Pleistocene,
called the Last Glacial Maximum (LGM) and dated to c. 20,000–18,000 rcbp. Reconstruction of the LGM environment of Siberia,
based on the latest models and compilations, provides a background for human existence in this region. Most of Siberia and
the Russian Far East at c. 20,000–18,000 rcbp was covered by tundra and cool steppe, with some forest formations in the river
valleys. Climate was much colder and drier than it is today. Eighteen Upper Paleolithic sites in Siberia are radiocarbon dated
strictly to the LGM, and at least six of them, located in southern parts of western and eastern Siberia and the Russian Far
East, have solid evidence of occupation during that time span. It seems clear that southern Siberia was populated by humans
even at the height of the LGM, and that there was no dramatic decline or complete disappearance of humans in Siberia at that
time. The degree of human adaptation to periglacial landscapes in the mid-Upper Paleolithic of northern Eurasia was quite
high; humans coped with the cold and dry environmental conditions using microblade technology, artificial shelters, tailored
clothes, and megafaunal bones as fuel.
An erratum to this article can be found at 相似文献