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31.
A simplified model useful for assessing economic losses due to moderate seismicity events in urban areas has been developed by studying the behavior of buildings before yielding their structural system, allowing for nonuniform stiffness along their height. In particular, buildings are modeled as cantilever shear beams with uniform mass and parabolic reduction of lateral stiffness. This particular stiffness distribution is relevant, as it could be expected to occur in buildings where earthquake action is a critical structural design criterion. The equation of motion governing the dynamic behavior of the proposed model is solved analytically, finding mode shapes in terms of first and second zero-order Legendre functions. The solution is verified by comparing it with results obtained from fine mesh finite element models. The effect of reducing the lateral stiffness is then studied in the first five modes of vibration. Results include modal periods, mode shapes, modal participation factors, and derivatives of mode shapes. In general, it is found that effects of reduction of lateral stiffness in mode shapes are moderate when the lateral stiffness in the free end is smaller than about seventy percent of the lateral stiffness at the fixed end, but become significant for larger reductions. Effects are particularly important for the derivative of the mode shapes, which could play a significant role in estimating interstory drift demands in buildings. Model usefulness is showcased by analyzing a test case where both acceleration and drift demands are assessed by considering uniform beams and beams with parabolic stiffness variation, finding notable improvements by considering the latter. 相似文献
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Csaba Albert Tóth Attila Rákóczi Sándor Tóth 《Conservation and Management of Archaeological Sites》2018,20(3):113-142
According to the Act of 1996 on nature protection, mounds (kurgans) are natural monuments protected nationally in Hungary. According to the law, all kurgans in Hungary were to be surveyed by 2002, and 1692 were included in the cadastre. Fewer than half of the kurgans remained intact due to numerous anthropogenic impacts. A high number of disturbing artificial buildings together with soil erosion, soil removal, and afforestation have significantly reduced the landscape value of kurgans. In 2002, 51.5% of the surveyed kurgans still represented some kind of a value and thus their protection became one of the most urgent tasks of nature conservation and archaeology. According to a Hungarian ministerial decree, established on the basis of an EU Council decree, the area of kurgans under cultivation must be removed from cultivation. By 2015, in the area of 90% of the kurgans under cultivation this land use, which caused significant erosion, was terminated. 相似文献
36.
Arturo Rodríguez Morató 《International Journal of Cultural Policy》2018,24(5):628-646
ABSTRACTThis article examines cultural policy strategies supporting urban regeneration, focusing on its particular characteristics in the Ibero-American context. We start by developing a systematic contrast between the different circumstances that have led to the emergence of these strategies in the Ibero-American sphere and in other parts of the world. Our examination of the Ibero-American regenerative experience also includes a consideration of the paradigmatic cases that arose initially in the Iberian Peninsula and the typological analysis of subsequent Latin American experiences. The consideration of all these different elements ends up providing a global vision of the specificity of the phenomenon in its Ibero-American context. 相似文献
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Aurora Higueras‐Milena Castellano Antonio M. Sáez Romero 《International Journal of Nautical Archaeology》2018,47(1):81-102
The area of La Caleta, north‐west of Cadiz, is a key location for studies of the relationship between the Phoenician city of Gadir and the ocean. The port channel and the small islets that characterize the area was one the busiest sectors of the city, and there are abundant underwater remains attesting to past commercial activities. The area also had an important religious role: two sanctuaries were located at the western end of the rocky promontories that surround the channel, and many items identified as offerings have been found. This article synthesizes previous research and provides an overview of the results of a recent project (2008–2010), which enables a thorough review of the development of the seascape and its use during the 1st millennium BC. 相似文献
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Diolinda Ramírez-Gutiérrez Heredina Fernández-Betancort Agustín Santana-Talavera 《International Journal of Heritage Studies》2018,24(6):634-648
In the area of cultural heritage, tourists’ experiences emphasise not only the moment and its personal nature but also socio-cultural traits. These experiences when expressed (social communications) are an important gateway to knowledge about tourists’ sense-making processes. This paper reports on the mediation between tourists and heritage sites via comments on a digital platform (TripAdvisor) about two Spanish tourist destinations with opposing characteristics and four heritage sites, which are analysed. The methodology used seeks to transcend the individual and anecdotal aspects of tourists’ comments. Indeed, the results obtained show the relevance of the humanisation and the discursive weight of heritage contexts in emotional/personal stories. Tendencies observed in non-regulated contexts confirm the role of a complex negotiation at cultural heritage sites and highlight the need to explore possible exchanges of sense in tourists’ encounters with such sites. 相似文献
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Pablo Navarro Esteve Santiago Yudici Oliver José Luis Denia Ríos María Teresa Martín Sánchez Jaime Rodríguez Pereña 《International Journal of Architectural Heritage》2018,12(2):169-177
The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire. 相似文献
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Barbara Voorhies Natalia Martínez-Tagüeña 《The Journal of Island and Coastal Archaeology》2018,13(1):43-65
A vibrant artisanal fishery of the brackish water marsh clam (Polymesoda acuta) is located in the lower Río Tempisque, Costa Rica. Fishermen harvest clams from shoals according to tidal and lunar cycles. They take most clams directly to riverside processing stations to be cooked and sold as salted meat, although some cooked clams are dried, and others sold live. Processing activities result in the formation of shellmounds that share significant similarities and some differences with ancient marsh clam shellmounds of coastal Chiapas, Mexico. In this study, procurement and processing activities are described and quantified, revealing the substantial amount of labor and skill involved in the modern fishery. Implications for archaeological preservation and predictions from optimal foraging theory are evaluated. 相似文献