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61.
A reliability-based methodology to estimate strength amplification factors for structures with asymmetric yielding is proposed. The approach is based on structural demand hazard analyses. Nonlinear time-history analyses of tridimensional simplified systems are carried out. The effects of two orthogonal components of the seismic ground motions and soil-structure interaction, are considered. Results show that the expected ductility demand of systems with asymmetric yielding may be much higher than those of symmetric systems. A simplified mathematical expression (which is function of the ratio between the fundamental vibration period of the system and that of the soil, ductility demand, and level of asymmetric yielding) is proposed to estimate the amplification factors. The expression is applied successfully to a 9-story reinforced concrete building exhibiting asymmetric yielding produced by tilting.  相似文献   
62.
The question of the Anthropocene has gained increased notoriety among archaeologists recently. Precisely because of that, it is in need of thorough critique. The aim of this article is not to rule out the concept of Anthropocene, but to point out some of its problems: the relationship of Anthropocenic discourses with the emergence of an all-embracing biopolitical science; the inadequacies of the term, which blames all humans equally for a specific effect of modernity and capitalism; its failure to accept a diversity of origins (but also the problem of accepting overly deep origins), and the shortcomings of adopting a geological framework for archaeology. I thus suggest that the discipline has to define its own eras – also for the contemporary period – and that the Age of Destruction could be an apt archaeological counterpart for the Anthropocene. One of the benefits of outlining an archaeological era is that it brings modernity and capitalism back to the fore, and with them issues of power and conflict that have been largely lost in recent post-anthropocentric debates.  相似文献   
63.
ABSTRACT

Outbound tour operators are key actors in international mass tourism. However, their contribution to more sustainable and inclusive forms of tourism has been critically questioned. Drawing from new institutional theories in organization studies, and informed by the case of one of the largest Scandinavian tour operators, we examine the corporate social responsibility (CSR) and sustainability work in large tour operators and the challenges faced in being more inclusive. On the basis of in-depth interviews with corporate officers, document analysis and media reports, we show how top-down coercive and normative pressures, coming from the parent company and the host society shape the ability of the daughter corporation to elaborate a more inclusive agenda. However, daughter companies do not merely comply with these institutional pressures and policy is also developed from the ‘bottom-up’. We show how the tour operator's sustainability work is also the result of organizational responses including buffering, bargaining, negotiating and influencing the parent organization. By creating intra and inter-sectoral learning and collaborative industry platforms, MNCs not only exchange and diffuse more inclusive practices among the industry, but also anticipate future normative pressures such as legislation and brand risk. Daughter organizations help shape their institutional arrangements through internal collaborative platforms and by incorporating local events and societal concerns into the multinational CSR policy, especially when flexible policy frameworks operate, and the corporate CSR agenda and organizational field are under formation. However, risks do exist, in the absence of institutional pressures, of perpetuating a superficial adoption of more inclusive practices in the mass tourism industry.  相似文献   
64.
ABSTRACT

Slender masonry structures such as towers, minarets, chimneys, and Pagoda temples can be characterized by their distinguished architectural characteristics, age of construction, and original function, but their comparable geometric and structural ratios yield to the definition of an autonomous structural type. These structures constitute a part of the architectural and cultural heritage. Their protection against earthquakes is of great importance. This concern arises from the strong damage or complete loss suffered by these structures during past earthquakes. Seismic vulnerability assessment is an issue of most importance at present time and is a concept widely used in works related to the protection of buildings. However, there is few research works carried out on developing the seismic vulnerability assessment tools for such structures.

This article presents a new method for assessing the seismic vulnerability of slender masonry structures based on vulnerability index evaluation method. The calculated vulnerability index can then be used to estimate structural damage after a specified intensity of a seismic event. Here, 12 parameters are defined to evaluate the vulnerability index for slender masonry structures. Implementation of this methodology is carried out in different types of slender masonry structures to develop vulnerability curves for these structure types.  相似文献   
65.
66.
Rural settlements growing crops and rearing animals are known as estancias in several South American countries. They played a prevailing role in the political and economic history of Argentina, particularly during the second half of the 19th century and the beginning of the 20th century. At present, many estancias are developing alternative activities, as recreation and tourism, in order to be able to subsist. The main problem lies in the fact that a non‐sustainable activity, frequently focused on the greatest economic yield, leads to the destruction of the heritage, instead of achieving its long‐term conservation. The purpose of this paper is to develop and verify a suitable model for the planning, execution and management of recreational and tourist activities in these rural settlements. As regards the scope of the concept of sustainable development, this methodology aims at achieving a balance between the recreational and tourist operation and the conservation of the rich heritage concerned.  相似文献   
67.
The influence of local geology and soil conditions on the intensity and the amplification of ground shaking are well known. Part of the old city center of Trieste is built on the site of a former salina, placed at a river mouth and is characterized by soft sediments several tens of meters thick. A new accelerometric station has been recently installed in a historical building, in order to analyse earthquake-induced site amplifications. This station has recorded five regional earthquakes and the related records are compared to those obtained at a nearby bedrock-installed accelerometeric station. Fourier and response spectra for all components are computed and both the H/V ratio and the reference station techniques are used to assess site effects. Noise measurements performed in the historical building, where the accelerometer is located, confirm these results. Relevant amplifications are detected in the frequency range of 2–4 Hz, particularly important for the type of buildings present in this part of the city.  相似文献   
68.
In structural analyses, masonry infill walls are commonly considered to be non structural elements. However, the response of reinforced concrete buildings to earthquake loads can be substantially affected by the influence of infill walls. In this article, an improved numerical model for the simulation of the behavior of masonry infill walls subjected to earthquake loads is proposed and analyzed. First, the proposed model is presented. This is an upgrading of the equivalent bi-diagonal compression strut model, commonly used for the nonlinear behavior of infill masonry panels subjected to cyclic loads. Second, the main results of the calibration analyses obtained with two series of experimental tests are presented and discussed: one on a single frame with one story and one bay tested at the LNEC Laboratory; and the second, on a full-scale four story and three-bay frame tested at the ELSA laboratory.  相似文献   
69.
Prehistoric pottery decorated with incisions or impressions filled with white and seldom coloured inlays is well documented in the archaeological literature, but the related in-depth archaeometric studies are sporadic. 43 decorated ceramic shards, dating from the Neolithic to the Bronze Age, and an Iron Age fibula from the archaeological site of Castello di Annone (Piedmont, North-Western Italy) were analysed with FTIR, Raman and XRPD for characterization of the ornamental pigments forming these inlays. Few white components were used as fillers, namely talc and bone ash (hydroxyapatite – Bone White), often as a mixture and seldom accompanied by other pigments (i.e. kaolinite and presumably secondary calcite). Comparison with freshly-heated biogenic hydroxyapatite proved that ancient Bone White pigment was calcined at about 900 °C. Such a process was kept separate from pottery firing as these white mixtures show absence of talc degradation by-products and sporadic presence of kaolinite, implying these ceramics were decorated only after firing in furnace. Actual presence of fluorapatite in bone ash could allow dating with the Fluorine Method, but lack of fluorine detection with SEM-EDS causes such an attempt to be impracticable so far. A pilot comparative study with a restricted but representative group (11) of coeval finds from other sites of Piedmont suggests that while recurrence of talc prevails in Castello di Annone from the Neolithic throughout the Bronze age, massive use of bone ash (Bone White) becomes widespread in the close Iron Age settlements, possibly consequent to a more efficient handling of its production technology.  相似文献   
70.
Four scleractinian coral taxa are described from limestones within a sandstone-shale séquence correlated with the Late Triassic Babulu Formation, Manatuto township, on the northern coast of Timor-Leste (East Timor). The coral fauna consists of three phaceloid taxa, Paravolzeia tìmorìca gen. et sp. nov., Craspedophyll ramosa sp. nov., Margarosmilia confluens (Münster), and a generically indeterminate solitary taxon attributed to the family Margarophylliidae. Ali four corals are related at various taxonomie levels to Carnian faunas from the Dolomites of northern Italy. Previously, only Norian coral faunas were known from the Triassic of Timor. The fauna exhibits both similarities to and differences from Carnian faunas of the Dolomites and helps confirm palaeogeographic affinities with the western Tethys, although during Late Triassic time Timor lay in the distant southeastern portai of the Tethys. Despite isolation from the western Tethys, the presence of two species foundalso in the Dolomites indicates that larvai dispersai occurred between the two areas.  相似文献   
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