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101.
The seismic vulnerability of housing stock in El Salvador was demonstrated during the recent 2001 earthquakes. Relative to other types of common residential construction, confined masonry dwellings performed well. A coordinated pilot study was conducted with the objective of improving the seismic resistance of this form of construction while reducing associated costs and greenhouse gas emissions. Laboratory tests examined brick strength in relation to firing temperature and duration. Analytical studies examined the potential for voided bricks to improve seismic performance, the reduction in demands associated with stiffening the roof diaphragm, and demands imposed on the roof bracing system. This pilot study identifies the potential for voided bricks to reduce construction costs and greenhouse gas emissions with negligible effects on performance. The addition of end-bay diagonal bracing at the roof level resulted in significant performance enhancements.  相似文献   
102.
As social constructions, heritage properties require the participation of all their stakeholders, especially in the case of UNESCO World Heritage Sites. The Atapuerca (Burgos, Spain) World Heritage Site is used as a test case for assessing the fulfilment of the local community’s development expectations, perceptions, and values. This paper is the first formal attempt to ascertain the opinions of residents in the surrounding villages — Ibeas de Juarros and Atapuerca — regarding the initiatives taken by the authorities, and the changes produced, since the site was included in the World Heritage List. The results show that many improvements can be made with the aim of democratizing the decision-making process, ensuring the involvement of the local community and improving their quality of life, in order to fulfil the spirit and recommendations of UNESCO.  相似文献   
103.
Cheia (early 5th millennium cal BC) is a prehistoric village in the Dobrodgea province in Romania. Its occupation is attributed to the Early Eneolithic period or Hamangia III phase. The exploitation of animal resources is heavily dominated by husbandry. Although cattle are dominant, they were complemented by caprines, mainly sheep, exploited for tender meat (as highlighted by a 6–12 months age class peak in the mortality profile). Sheep reproduction patterns were investigated through stable isotope analyses in order to characterize the annual rhythms of slaughtering for tender meat acquisition while informing a more general picture on sheep demographical management and animal husbandry at the settlement. Results from δ18O analysis on second and third molar enamel were modeled and compared with modern reference populations. Sheep births took place over less than four months, from late winter to early summer. From this it could be concluded that tender meat could be provided most of the year, excepted over short period in early summer. Finally, comparison of datasets obtained on the M2 and M3 suggests that the M2 presents a more accurate representation of birth seasonality due to lower inter-individual variability in the chronology of tooth growth.  相似文献   
104.
A new microdomatid gastropod, Eopagodea sevillana gen. and sp. nov., is described from the Late Ordovician (pre-Hirnantian Ashgill) limestones of Seville, Ossa Morena Zone, Spain. Palaeozoic microdomatids lived in shallow-water environments and were restricted to warm-water regions. Occurrence of microdomatid gastropods in the pre-Hirnantian Ashgill limestones of the Cerrón del Hornillo syncline (Ossa Morena Zone, Spain) is interpreted as an example of an influx of warm-water faunal elements into the otherwise cool to cold climate of the Mediterranean region during a short-termed, pre-Hirnantian increase of palaeotemperatures. The Late Ordovician microdomatid genus Daidia Wilson, 1951, is revised and two new Late Ordovician (Ashgill) subspecies of Daidia cerithioides (Salter, 1859) are described: Daidia cerithioides sewardensis n. subsp. from the Don River area of the York Mountains, Seward Peninsula, western Alaska, and Daidia cerithioides wilsonae n. subsp. from the Little East Lake Formation of northwestern Maine.  相似文献   
105.
Interaction between hominins and carnivores has been common and constant through human evolution and generated mutual pressures similar to those present in worldwide modern human-carnivore conflicts. This current interaction is sometimes violent and can be reflected in permanent skeletal pathologies and other bone modifications. In the present paper, we carry out a survey of 124 forensic cases of dangerous human-carnivore encounters. The objective is to infer direct hominin-carnivore confrontation during the Pleistocene, which is important to understand behavioral changes during human evolution. In addition, the case of Neanderthals is analyzed in order to find evidence of past attacks using forensic observations. The results obtained pose that Neanderthals could potentially have been involved in dangerous encounters during the Pleistocene, validating our methodology to approach past attacks from a forensic perspective.  相似文献   
106.
This paper seeks to contribute to the development and improvement of displacement-based design procedures, proposing improved ductility-equivalent viscous damping relationships for steel moment-resisting framed structures with dissipative beam-to-column partial-strength joints. These relationships can be used directly in procedures like the Direct Displacement-Based Seismic Design (DDBD) that uses effective stiffness, ductility-equivalent viscous damping relationships, and period-displacement relationships in a performance-based design approach. To this end, a finite element model of a steel beam-to-column sub-assemblage, characterized by an extended end-plate, is developed in ABAQUS. The model, which is validated against monotonic and cyclic experimental data obtained in previous research, is employed to carry out non-linear time-history (NLTH) analyses, using real records scaled to target several levels of ductility demand. A procedure is then proposed and applied to determine the ductility-equivalent viscous damping relationships of the sub-assemblages. The equivalent linearization technique is applied to the non-linear responses obtained in the NLTH analyses, using an elastic single degree of freedom structure and the elastic displacement spectra. The influence of joints mechanisms and of the dynamic characteristics of the structure in the equivalent viscous damping is investigated, and an expression for ductility-equivalent viscous damping is proposed. The proposed expression represents a clear improvement in relation to the existing expressions available in literature.  相似文献   
107.
Risk communication programs (RCPs) can contribute to the improvement of community health in marginalized settlements by improving health-related information and practices. Yet, there is a need to include young people's concerns in the design and implementation of RCPs. This study analyses young peoples’ risk perceptions in the city of San Luis Potosí, Mexico, using visual methods such as drawings and photography. Research was conducted with 74 students from two deprived urban neighborhoods. Results indicate that the use of visual techniques enabled them to identify environmental health risks such as unhealthy sedentary habits and the exposure to hazardous items. We conclude that visual methods may help young people to critically reflect on everyday elements in their environment that affect their well-being. By giving them a voice in a reflexive way, visual methods may engage young people as key multipliers in the awareness raising process, and promote their sense of everyday agency.  相似文献   
108.
In the course of an archaeological project in the southern Chad Basin of Nigeria, excavations were conducted at several deeply stratified mound sites that date from the Late Neolithic to the Late Iron Age. As a way to complement the ceramic sequence obtained so far and to link it with today's pottery tradition, a small excavation was conducted at a site that dates to the turn of the nineteenth to the twentieth century A.D. A pottery assemblage was discovered that shows obvious links to today's tradition but notable breaks with those of the nineteenth century and earlier. This break in decoration style and technique is interpreted as an archaeologically visible expression of changing ethnic identity. This ethnic change and the associated spread of the ceramic tradition can be linked with the expansion of the sphere of power of the Kanem-Borno Empire into the area south of Lake Chad after the sixteenth century A.D.  相似文献   
109.
Portable X-ray fluorescence (pXRF) geochemical analysis on obsidian from five Formative period (1200 BCE to AC 100) sites from Tlaxcala, Mexico, has revealed that most of the material had similar values to those found in the closest obsidian source, named El Paredón, Puebla. Nevertheless, initial analyses did not resolve whether these materials came from the same caldera or from a specific obsidian deposit. Here we present a methodology that allows the identification of obsidian subsources. The results reveal that Tlaxcalan populations took advantage of a specific obsidian deposit called Tres Cabezas, Puebla, providing valuable new data to identify associated regional exchange networks.  相似文献   
110.
Carlos Serrano 《对极》2023,55(2):599-619
This article focuses on how educational institutions are crucial sites for understanding how racial capitalism and anti-Black violence are reproduced. Centring Chapel Hill, home of the University of North Carolina (UNC), and its neighbouring town of Carrboro as a university town built by racial capitalist and anti-Black practices, I analyse how the university functions as a social reproductive force that structures the town and its local public education system. Building on my ethnographic research, Black studies literature, and Black geographic thought, I argue that the university partakes in the political, economic, and ideological restructuring of a community that enables hierarchical differences to be produced in schools in terms of how success is rooted with liberal notions of the individual and proximity to whiteness. Paying attention to these relationships challenges us to think about the need for the total eradication of oppression in all forms to truly have liberated educational spaces.  相似文献   
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