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Los Naranjos is one of the most important pre-Columbian human settlements of Honduras related to the south-easternmost border of the Mayan civilization. Although the archaeological site mostly spans from 850 BC to 1250 AD, the present obsidian study was only focused on the Preclassic and Early Classic periods (Jaral, 800–400 BC and Edén, 400 BC–550 AD) where undamaged blades and/or retouched obsidian flakes are rare. In this way, the INAA analyses of 17 obsidian samples, compared with major-trace elements data of Honduran and Guatemalan obsidian sources, are mostly representative of waste flakes. Lithic artifacts of Los Naranjos such as sandstones, basalts, and quartzites come from local geological outcrops; whereas, obsidian provenance has to be searched from sources which are located within a radius up to 300 km far away. San Luis, La Esperanza, and Güinope obsidian sources are located in Honduras while the three most exploited Highland Guatemalan obsidian outcrops, which have been dominating long-distance trade in the Maya area mostly for the Classic-Postclassic periods, are San Martin de Jilotepeque, El Chayal, and Ixtepeque. An Ixtepeque provenance, for all the investigated obsidian samples of Preclassic and Early Classic periods found in the Los Naranjos Archaeological Park, was established, thus emphasizing a long-distance source (180 km). This also confirms that Ixtepeque represents the most important provenance of the obsidian artifacts found in archaeological sites of Western and Central-Western Honduras. The possible role played by some of the most important rivers of Guatemala and Honduras as waterway networks of transport was finally pointed out. New INAA chemical data from the Honduran obsidian source of La Esperanza (“Los Hoyos”, 4 samples) are also reported in this paper.  相似文献   
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Documentation of maritime heritage is essential for its protection, and for reference in restoration and renovation processes. These functions become problematic in the case of historical ships and boats that lack lines drawings. The purpose of this paper is to describe a procedure for creation of lines drawings based on the shape analysis of surviving historical boats or their small-scale models with the help of reverse engineering (RE) techniques. The paper describes how digital photogrammetry and the iterative method were used to analyze the shape of three historical boats: Tomahawk, Refola and Nada. The application of the proposed procedure produced the lines drawings of the boats as its result. The accuracy of the 3D CAD model obtained with the photogrammetric technique was verified by comparing it against a more accurate 3D model produced with the help of a RE laser scanner. The examination of the resulting lines drawings proves that the digital photogrammetry process and the proposed iterative method are adequate tools for developing lines plans of boat models. The research offers the methodological basis for the creation of an archive of lines drawings of historical boats. Such an archive would provide reference for philologically correct restorations, and permit definition and classification of distinctive elements of various types of historical boats, particularly those produced in the Campania Region.  相似文献   
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This paper presents, for the first time, a detailed study, from an archaeological perspective, of the morphological characteristics of the starch grains within the kernels of selected native wild grasses found in the Central Pampas of Argentina. We compared native wild grasses to maize starch grains, which can be distinguished from each other based on their size, shape and other attributes. The majority of the studied grains did not share morphological characteristics with maize starch grains. Considering this, it can be said that, if irregular and polyhedral grains with transverse or radial fissures dominate the starch assemblage, maize identification may be done on the basis of both morphology and size. Additionally, this research contributes to the characterization of the starch grains of the Panicoideae subfamily, which includes maize. Several classes of simple and compound starch grains are described and defined for native species of Pooideae, Chloridoideae, Arundinoideae, and Panicoideae subfamilies. The results obtained may constitute a baseline for the future determination of maize and wild grass use in archaeological contexts belonging to Middle/Late Holocene hunter–gatherers in the Pampas of Argentina and neighboring areas.  相似文献   
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Timber structures can be degraded during their life both by structural problems and by biological degradation factors like fungi and insects. The occurrence of those biodegradation agents could lead to a loss of their structural integrity, in the absence of appropriate maintenance. An early assessment of the decay is even more important when the wooden structures are part of historical buildings, in the interest of conservation of cultural heritage.

This article presents an application of microwave reflectometry for the in situ evaluation of timber structures. The measurement system allows detecting anomalies inside the material in a non-destructive and non-invasive manner.

The reflection coefficient is measured by means of a vector network analyzer (VNA) using a double-ridge antenna which transmits the continuous-wave (CW) microwave signal and receives the signal reflected by the material under investigation.

Measurements on laboratory models demonstrated the feasibility of the method. Results obtained on timber beam sections, compared with the findings of traditional investigation methodologies, demonstrate the potentiality of microwave reflectometry, suggesting its possible usefulness during the diagnostic phase as a non-invasive tool for preliminary screening.  相似文献   

6.
In this article we calculate an indicator of social and economic development using the DP2 distance method to measure the disparities in Objective-1 regions of southern European countries for 2006. In addition to per capita income, socio-economic components such as health, education, employment, scientific and technological development and infrastructure provision have been incorporated into the index. We examine the issue of whether the Europe Union regions included in the Convergence Objective achieved a lower level of development than the regions no longer covered in this objective for the 2007–2013 programming period by establishing a territorial classification based on the value yielded by the variables of the DP2. Our indicator constitutes a novel contribution insofar as it was constructed using a large number of variables. In essence, we show that not all the regions of the Convergence Objective presented a lower level of economic and social development than those that lost this consideration between 2007 and 2013 and the opposite.  相似文献   
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This paper examines the return to infrastructure in the European Union regions in a spatial framework. It innovates on the earlier literature on infrastructure and growth by a combination of regional focus, disaggregation of infrastructure types and consideration of spatial dependence. Different types of infrastructure capital are considered as determinants of economic performance at the Nomenclature des Unités Territoriales Statistiques level. To account for growth spillovers among regions, a spatial Durbin model is estimated. The results confirm the important role of infrastructure and identify the highest rates of return as associated with telecommunication, quality and accessibility of transportation networks, with a positive impact of roads and railways.  相似文献   
8.
This paper examines how the practices of heritage tourism reproduce identities in and of Fredericksburg, Virginia. In particular, we focus on the everyday practices of tourism workers who are essential in the representation and reproduction of this heritage space. In so doing, we want to move away from research in geography that theorizes representation and embodiment as distinct realms of experience and inquiry. Instead, we argue that representation is work and within this very material process, city workers weave memory with history as they guide visitors through ‘America’s Most Historic City'. Through an examination of three of Fredericksburg's tourism work environments we show how representations succeed in reproducing heritage tourism spaces precisely because representation is work.  相似文献   
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In Italian classical archaeology, the definitive adoption of the stratigraphic excavation method occurred later than in other European countries. This methodological shift took place in Italy in the 1970s. We aim to scrutinize some points of the established historiographical reconstruction. We focus on three scholars regarded as “key figures” in the birth of Italian stratigraphic archaeology, yet all of the first half of the twentieth century, Giacomo Boni, Nino Lamboglia, and Luigi Bernabò Brea. We examine the origin of their stratigraphic approach and thus their relationship with prehistoric research. This is also an opportunity to reflect upon the conceptual and methodological transfer from one type of archaeology to another. In general, through comparison of these scholars, we aim to highlight some key factors in the establishment of a stratigraphic method in the history of archaeology.  相似文献   
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