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51.
The aim of this study was to image buried remains and appoint buried Hellenistic street system, and identify minerals and rock types of the ancient city of Nysa, one of the most important historical sites of Turkey. This study used polarized microscope and confocal Raman spectroscopy (CRS) ground penetrating radar (GPR) method, to identify the buried remains, rock types and minerals.  相似文献   
52.
Abstract

The rock-cut monuments in the ancient city of Petra in Jordan form an outstanding tangible heritage site. Unfortunately, this important part of the world's cultural heritage is gradually being diminished due to weathering and erosion problems. In this research, an approach combining in situ surveying and laboratory analysis is applied in order to provide sufficient and comprehensive data regarding the documentation and evaluation of the status of the Al-Deir monument in Petra. The purpose was not only to quantify the damage, but also to make a first step towards creating a 3D monitoring programme of the deterioration rate. The approach presents a correlation study between the environmental condition and the surface weathering damage, using 2D mapping of the weathering form and accurate 3D realistic modelling from laser scanning and digital photogrammetry. The 2D mapping provides detailed weathering damage information for the entire stone surface of the monument, whereas the 3D modelling provides information on the spatial distribution and texture of the damage. Additionally, the 3D digital model can provide reference data as an exact guide to the restoration needed. In order to support the visual presentation of 3D surface details, a hybrid approach combining data from laser scanning and digital imagery was developed.

Studies of stone texture and spatial distribution of soluble salts were carried out at the monument in order to explain the mechanism of the weathering problem. Relative humidity, temperature, and wind are the main factors in the salt damage process. In order to study the effect of these conditions in the salt crystallization process a series of fieldwork investigations and laboratory work were undertaken. The results show that visible zoning of weathering damage is correlated to different salt concentrations.  相似文献   
53.
Abstract

Digital technology has changed our approaches to cultural heritage documentation radically and promises to continue to bring rapid changes. Photographic and non-photographic (graphic) documentation tools are merging in one process, in which digital photographic technology is the main base. Due to digital technology, there is an increasing gap between specialist technicians and non-technical users involved in heritage documentation. 3D approaches are still not popular among users in cultural heritage. However, in order to build a bridge between the specialist and non-technical users, a dialogue between them needs to be developed, not only to discuss issues of data precision and 3D accuracy, but also visualization production systems, which can now easily be achieved by modern digital photographic technology.

This paper presents a comparative evaluation and synthesis of cultural heritage documentation methods and survey techniques currently available, focusing on the needs and requirements of non-technical users of heritage documentation. It attempts to clarify some new aspects in cultural heritage documentation and to assess the impact of current technology. The paper undertakes a comparative evaluation of the potential application of digital methods in documentation — and examines issues such as quality, accuracy, time, costs and specific skills required — from pre-electronic techniques (hand measurement) to 3D laser scanning, which today represents the most advanced technology available for measuring and documenting objects, structures and landscapes.  相似文献   
54.
烫样是研究清代皇家建筑的珍贵文物,为配合文物信息数字化工作的开展,针对烫样数据的采集和处理方法进行了深入研究。在综合考虑多种数据采集方法的特点及烫样数字化记录的难点后,选择使用手持式三维扫描仪与多视角三维重建技术相结合的方式来进行烫样的基础数据采集,并通过实践总结出了一套完整的数据采集和处理工作流程。与此同时,针对成果可能的应用方式做了些许尝试,且为数据的后期维护与进一步利用拟定了数据管理系统的建设方案。  相似文献   
55.
Expanded border enforcement has made unauthorised migration to the US more risky, costly, and prone to failure. Research on the material consequences of border enforcement for migrant‐sending households in Central America reveals that the economic hardships enforcement exacts on migrants at times diminishes enforcement's desired deterrent power. Heightened risks have driven up the cost of migration and pushed many to fund their trips through loans. Consequently, migrant detention, deportation, or death can result in poverty and privation for indebted households and the seizure of loan collateral, typically homes and land, in turn prompting crises in household reproduction. With a US wage the most viable means to ameliorate economic hardships, enforcement outcomes push some to return migration. Our findings suggest that US border enforcement efforts at times perpetuate the very unauthorised migration they seek to impede, while also helping to reproduce the border itself by deepening the marginalisation that drives migration decisions.  相似文献   
56.
Japhy Wilson  Manuel Bayón 《对极》2018,50(1):233-254
This paper explores the entanglement of ideology and materiality in the production of the spaces of 21st century socialism. “Millennium Cities” are currently being constructed for indigenous communities throughout the Ecuadorian Amazon, with revenues derived from petroleum extracted within their territories. As iconic spatial symbols of the “Citizens’ Revolution”, the Millennium Cities would appear to embody “the original accumulation of 21st century socialism”—a utopian state ideology promising the collective appropriation of natural resources without the dispossession of the peasantry. Drawing on extensive field research, we argue that they are better understood as a simulation of urban modernity that is symptomatic of the predominance of ground rent in South American capitalism, and which conceals the violent repression of an autonomous indigenous project of petroleum‐based modernization. The original accumulation of 21st century socialism can therefore be interpreted as a “fantasy of origins”, which functions to reproduce the primitive accumulation of capital.  相似文献   
57.
ABSTRACT

Historical masonry structures are often located in earthquake-prone regions and the majority of them are considered to be seismically vulnerable and unsafe. Historical masonry towers are slender structures that exhibit unique architectural features and may present many inadequacies in terms of seismic performance. The seismic protection of such typologies of structures and the design of effective retrofitting interventions require a deep understanding of their behavior under horizontal loads. This paper presents the results of the seismic performance evaluation of historical masonry towers located in Northern Italy. A large set of case studies is considered, comprising a significant number of towers with high slenderness and marked inclination. First, a preliminary assessment of the dynamic behavior of the different towers is carried out through eigenfrequency analyses. Then, non-linear dynamic simulations are performed using a real accelerogram with different peak ground accelerations. A damage plasticity material model, exhibiting softening in both tension and compression, is adopted for masonry. The huge amount of results obtained from the non-linear dynamic simulations allows a comparative analysis of the towers to be performed in order to assess their seismic vulnerability and to show the dependence of their structural behavior on some geometrical characteristics, such as slenderness, inclination, and presence of openings and belfry. The evaluation of different response parameters and the examination of tensile damage distributions show the high vulnerability of historical masonry towers under horizontal loads, mainly in the presence of marked inclination and high slenderness. Some general trends of the seismic behavior of the towers are deduced as a function of the main typological features.  相似文献   
58.
This article investigates the determinants of political cleavages composing the structure of political attitudes in Jordan, Tunisia, and Yemen following the Arab Spring. Further, it tests whether political cleavages carry predictive weight on ordinary citizens’ electoral choices in general elections. Using the Sixth Wave of the World Values Survey, discriminant analysis was conducted to generate the dimensionality, type, and structure of political attitudes in the three nations. Findings suggest that the structure of political attitudes in Jordan, Tunisia, and Yemen is multidimensional: the Islamic‐Secular division, a conflict along economic policy visions and an emerging divisive dimension concerning political reform. Evidence indicates that political cleavages do not possess significant predictive power in determining voters’ choice at elections booths. This research also points to the significance of social transformation processes such as modernization and globalization in causing a shift in values among ordinary citizens in the Arab World. This research argues that in countries where the effects of modernization and globalization are higher, a weakening of the Islamic‐Secular division is witnessed. This research is important since it paves the way for further empirical analysis on political ideology in the Middle East. It shatters conjectures concluding that Arab polities are only divided by a single hierarchical dimension: Islamic‐Secular. It contributes to comparative research on the dimensionality of political ideology by showing that the Arab World is similar to the industrialized world in the dimensionality, nature, and structuration of political ideology.  相似文献   
59.
The article examines the legislative and judicial tasks of Islamic jurists and how they carried it out in constitutional or general legal structure. While the Pakistani experiment was inspired by the Iranian model of jurists' involvement in legislatures, Egypt took a different path by not recognizing any official role for Islamic jurists with ambiguous recognition of Islamic jurisprudence. The legislative role could take the form of incorporating Islamic jurists into the legislature, establishing a committee partially made up of Islamic jurists, or handing over some legislative task to an Islamic jurisprudential institution. Despite the fact that Islamization was intended to respond to the people's requests, it employed autocratic and authoritarian mechanisms. The project attempted to replace the typical class of socially recognized jurists with appointed committees entrusted with Islamic codification. The experiment was challenged for its operation and its Islamicity but never introduced Shari'a courts or Islamic clerical legislation.  相似文献   
60.
R. Chen  G. Tian  W. Zhao  Y. Wang  Q. Yang 《Archaeometry》2018,60(5):1122-1134
The study aims at providing the spatial distribution and potential structure of the burial mounds at the Sifangling site, Hepu Han Tombs, in southern China. We implemented an electrical resistivity tomography (ERT) technique to obtain high‐resolution imaging of archaeological targets, considering the challenging environment and the depth of the burials. Three ERT profiles were tested above a small ancient mound previously detected by exhaustive archaeological drillings, following which 18 ERT profiles with angular separation were performed on the largest mound at the test site, without any a priori archaeological evidence below the surface. Then, a series of two‐dimensional (2D) profiles were combined as a ‘pseudo‐3D’ volume, which allowed a detailed characterization of the burial mound, and iso‐resistivity surfaces were also calculated to emphasize the location and spatial extent of the target. The results gave an effective identification of the funeral chamber and its structural details, and allowed detailed pre‐excavation planning.  相似文献   
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