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21.
    
We compare the industrial dynamics in the core, semi‐periphery and periphery in the Netherlands in terms of firm entry‐exit, size, growth and location patterns. The contribution of our work is to provide the first comprehensive study on spatial differentiation in industrial dynamics for all firm sizes and all sectors, including services. We find that location patterns are largely consistent with the spatial product lifecycle model: traditional Fordist sectors are over‐represented in the periphery, while sectors associated with the ICT paradigm are over‐represented in the core, with the notable exception of science‐based manufacturing. Second, where the industrial dynamics in manufacturing sectors follow the predicted patterns, the industrial dynamics in service sectors largely contradict product lifecycle theory. We conclude that the spatial product lifecycle theory applies well to traditional manufacturing, while more specific theories are required to understand the location and industrial dynamics of science‐based industries and service industries.  相似文献   
22.
African Archaeological Review - A set of beads made of glass, gastropod mollusk shell, and fishbone from a Swahili occupation level on Ibo Island (northern Mozambique) is dated to the eleventh and...  相似文献   
23.
Regional policies across Europe aim at stimulating regional development in non-core regions through fostering entrepreneurship. However, the policies applied in non-core regions and the concepts of entrepreneurship these policies are based on differ. Therefore, the goal of this review is to identify different understandings of entrepreneurship and their role for regional development processes in European non-core regions. To this end, empirical studies investigating entrepreneurship in European non-core regions from 1999 to 2011 were analysed. The results of the analysis are presented along three drivers and outcomes of entrepreneurship identified inductively from the literature: innovation, social capital and institutional change. We made out seven different types of entrepreneurship in European non-core regions. These seven types of entrepreneurship comprise particular mechanisms through which they stimulate regional development. Further research should study the interplay between these different mechanisms of regional development in non-core regions which may induce a more territorial approach to understand entrepreneurship in non-core regions across Europe.  相似文献   
24.
Among the various types of industrial solutions used to store goods and products, the light duty hand loaded shelving rack (SR) typology represents a very popular solution for domestic applications, libraries and for superstores/markets open to the public. Despite the limited cost, an eventual collapse could result in significant damage of stored goods, injuries, and potentially the loss of human life, with the possible consequence of a long suspension of commercial activities. This reflects directly on the great importance of a correct design that, despite the large use of SRs, is nowadays developed with approaches characterized by inadequate levels of reliability.

A research program on SRs is currently in progress in Italy, with the aim of improving the rules for both static and seismic design and this article presents a combined experimental-numerical study. Both component and pushover tests have been carried out, that are shortly summarized. Overall frame response has been simulated by means of advanced finite element software able to capture key features of the nonlinear response of slender frames with mono-symmetric cross-section members.  相似文献   
25.
The question as to whether an extracellular matrix exists between cells in the adult brain has been debated since the end of the last century. In the early years, zones containing neuropil and glial processes were mistakenly believed to represent this substance. But Golgi's discovery of the “perineuronal net” paved the way for future study of the true extracellular matrix. In the 1950s, application of histochemical techniques established the existence of interstitial material between nerve cells. Unfortunately the similarity between the pericellular distribution of this material and Golgi's “pericellular nets” was overlooked. The detection of an extracellular volume fraction in the central nervous system furnished further indirect proof for the existence of an extracellular matrix in the brain. However, the repeated failure of electron microscopy to reveal a substantial space between cell processes undermined the acceptance of the concept of “extracellular matrix” in the central nervous system. Nowadays this concept has, however, been firmly established.  相似文献   
26.
Commonly used in archaeological contexts, micromorphology did not see a parallel advance in the field of experimental archaeology. Drawing from early work conducted in the 1990’s on ethnohistoric sites in the Beagle Channel, we analyze a set of 25 thin sections taken from control features and experimental tests. The control features include animal pathways and environmental contexts (beach samples, forest litter, soils from the proximities of archaeological sites), while the experimental samples comprise anthropic structures, such as hearths, and valves of Mytilus edulis (the most important component of shell middens in the region) heated from 200 °C to 800 °C. Their micromorphological study constitutes a modern analogue to assist archaeologists studying site formation and ethnographical settings in cold climates, with particular emphasis on shell midden contexts.  相似文献   
27.
The study of fabrics, that is, the analysis of the orientation and slope of archaeological and sedimentary materials associated with the Middle Palaeolithic/Upper Palaeolithic (MP/UP) transition at Cova Gran shows substantial differences. Archaeological assemblages are characterised by greater isotropy in the fabrics than the sedimentary levels within which they are located, indicating that these differences may be generated by anthropic processes. One of the anthropogenic processes associated with horizontal and vertical displacement of archaeological artefacts is trampling and circulation caused by later occupations. In order to evaluate the effect of movement on materials, we undertook experiments simulating geological and archaeological conditions at Cova Gran. The results show that human trampling does not cause major isotropy in fabrics, but arranges archaeological assemblages towards planar or linear materials according to surface geometry. We were not able to replicate the fabric pattern of materials from the archaeological levels of Cova Gran, suggesting that they must be associated with the activities of human occupation at each level.  相似文献   
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The full release and circulation of excavation results often takes decades, thus slowing down progress in archaeology to a degree not in keeping with other scientific fields. The nonconformity of released data for digital processing also requires vast and costly data input and adaptation. Archaeology should face the cognitive challenges posed by digital environments, changing in scope and rhythm. We advocate the adoption of a synergy between recording techniques, field analytics, and a collaborative approach to create a new epistemological perspective, one in which research questions are constantly redefined through real-time, collaborative analysis of data as they are collected and/or searched for in an excavation. Since new questions are defined in science discourse after previous results have been disseminated and discussed within the scientific community, sharing evidence in remote with colleagues, both in the process of field collection and subsequent study, will be a key innovative feature, allowing a complex and real-time distant interaction with the scholarly community and leading to more rapid improvements in research agendas and queries.  相似文献   
30.
The aim of this article is to focus on the technology of archeological plasters at Teotihuacan (Central Mexico), from the Classic Period (200–650 A.D.), focusing in the study of Teopancazco, a neighborhood center in the city. Petrographic and chemical analyses by OM, SEM-EDS, and LA-ICP-MS were conducted to characterize samples from different constructive phases and sectors of the neighborhood center, to determine the provenance of the raw materials employed in the manufacturing (e.g., volcanic glass shards) and to assess whether a shift occurred in the manufacturing of plasters and in the procurement strategies of raw materials during the different phases. The results of the analyses show that almost no changes occurred in the making of the plaster during more than four centuries and allow us to consider the presence of a technological style in their manufacture, which is characterized by the making of plaster by mixing lime with volcanic glass shards, which in the case of Teopancazco were derived from the Altotonga (Veracruz) magmatic system. The data at our disposal suggest that this style was developed in Teopancazco and later introduced throughout the city of Teotihuacan in the Early Xolalpan phase (A.D. 350), although we still do not know whether the provenance of the raw materials is the same. The wide distribution of this technological tradition could be due to the technological properties of the materials and/or the influence of the intermediate elite who ruled over Teopancazco. The paper confirms that the study of material culture and technology sheds light on broader cultural aspects of ancient societies.  相似文献   
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