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91.
Transport of resources is a major feature of Oldowan hominin technological adaptations. Comparisons between different Oldowan localities often employ measures of transport that are based on artefact attributes as proxies for the intensity of raw material utilization. The Technological Flake Category system [Toth, N., 1985. Oldowan reassessed: a close look at early stone artifacts, Journal of Archaeological Science 12, pp. 101–120] has been used extensively to infer the relative intensity of lithic reduction within Oldowan assemblages. Here we use a large experimental sample to test the relationship between a flake's stage in a reduction sequence and various quantitative attributes. We demonstrate how many previously described attributes are affected by initial core size. We then develop a multiple linear regression model that incorporates several variables to predict the placement of a flake within a generalized reduction sequence. The model is then applied to Oldowan assemblages in the Koobi Fora Formation which explores the strengths and weaknesses of different methods of investigating reduction intensity on an assemblage level.  相似文献   
92.
Between the Upper Palaeolithic and the spread of metallurgy stone-tipped projectiles were of great importance both for subsistence and as weapons. Whilst finds of embedded projectile points in human and animal bone are not uncommon, identifications of such wounds in the absence of embedded points are rare. Previous experimentation involving archaic projectiles has not examined the effects of stone-tipped projectiles on bone. This paper presents the results of experiments in which samples of animal bone were impacted with flint-tipped arrows. The results demonstrate that positive identifications can be made, both grossly and microscopically, of bony trauma caused by flint projectiles. In addition, flint projectiles are shown to often leave small embedded fragments, which can also be identified microscopically. These results compare well with archaeological examples of suspected ‘arrow wounds’ and the article demonstrates the practical application of this data in identifying such injuries. By facilitating the recognition of projectile trauma these findings will have significance both for the investigation of hunting strategies and levels of conflict amongst early human societies.  相似文献   
93.
The morphology of Acheulean handaxes continues to be a subject of debate amongst Lower Palaeolithic archaeologists, with some arguing that many handaxes are over-engineered for a subsistence function alone. This study aims to provide an empirical foundation for these debates by testing the relationship between a range of morphological variables, including symmetry, and the effectiveness of handaxes for butchery. Sixty handaxes were used to butcher 30 fallow deer by both a professional and a non-professional butcher. Regression analysis on the resultant data set indicates that while frontal symmetry may explain a small amount of variance in the effectiveness of handaxes for butchery, a large percentage of variance remains unexplained by symmetry or any of the other morphological variables under consideration.  相似文献   
94.
This study examines the seismic behavior of the minaret of the well-known historical structure “Sultan Ahmed Mosque” under strong earthquake motion. Despite their slenderness and height, minarets are towers with well-established earthquake resistance. In general, these structures were constructed adjacent to the main structure and/or its components. Hence, it is expected that the dynamic behavior of the minarets is influenced by the dynamic characteristics of the adjacent structures as well as the contact conditions. In the presented study, the dynamic behavior of the M6 minaret of the Sultan Ahmed Mosque, which is in contact with the portico that surrounds the courtyard of the mosque, is considered. Ambient vibration tests were conducted on site in order to identify the individual and coupled vibration modes of the minaret and the portico. A finite/discrete model was developed and seismic analysis was carried out. The comparative study reveals considerable differences in responses of different models under strong and very strong earthquake motion.  相似文献   
95.
This paper explores the relationship between standing vegetation and dung from hay-fed cattle and sheep. In an experimental study, hay is retrieved from a known hay field, surrounded by a semi-open landscape of hedgerows, forests and heather fields. The hay is fed to cattle and sheep, after which the dung is collected and from which the botanical remains are analysed, according to archaeobotanical standards. The results from the macro-remains are compared to vegetation relevés from the hay field. The pollen analysis is compared to both the hay field and the surrounding vegetation. Results from the plant macro remains provide an excellent representation of the vegetation in the field itself on the presence/absence level. Pollen analysis reflects the regional vegetation very well and are comparable with ‘surface samples’.  相似文献   
96.
97.
Urban heat island (UHI) effect is an important impact factor of the regional climate and ecological environment. How to observe and analyse the spatial distribution of UHI has become an important issue of urban environmental research. In this paper, the near‐surface air temperature of Beijing was derived based on the Landsat/TM satellite imagery on 26 July 2011 to study the near‐surface UHI. A statistical model at 195‐m window size was established to estimate the air temperature, using land surface temperature, normalized difference vegetation index, altitude, and surface albedo as independent variables. The mean absolute error (MAE) of the model was 0.87°C, and the R2 was 0.66, indicating that the method can be used to effectively estimate the air temperature. The air temperature distribution obtained from remote sensing revealed that the UHI effect in Beijing was very significant and showed a concentrated pattern. The heat island intensity was stronger in the southern part than in the northern part of the city. In addition, the relationship between the air temperature and impervious surfaces was analysed. The air temperature increased with increasing impervious surface coverage, and the rate of change depended on the impervious surface coverage. When the impervious surface coverage was below 40 per cent, the temperature increased rapidly with increasing impervious surface coverage, and when the impervious surface coverage was above 40 per cent, the temperature increased slowly. This study provides a new approach to monitor near‐surface UHI and reveals its relationship with impervious surface, providing a scientific reference for urban planning and environmental assessment.  相似文献   
98.
Here we present a database of responses by South African agate and chalcedony to heat treatment. This will assist analyses of heated stone tools not only in South African archaeological sites, but wherever heated agate and chalcedony pieces were knapped. The minerals are abundant worldwide. To replicate potential heating methods during the Stone Age we placed some minerals in a wood fire, some under coals, and others were buried in sediments beneath fires. Thermal responses include lustrous flaked surfaces, pot lid fractures, semi-circular internal fractures, rough internal surfaces, and crazing. Aerobic heating is implied by pot lid fractures. To explain the thermal responses we analyzed the minerals using X-ray fluorescence, Raman spectroscopy, and carbon and sulfur analyses. Our chalcedony contains more water and impurities than agate, making it more vulnerable to thermal damage. Our method of combining field experiments with chemical analyses has global applications even though we expect that mineral components of agate and chalcedony will vary slightly in different parts of the world.  相似文献   
99.
甘肃省博物馆文物保护部对灵台八十件青铜器进行了科学的保护与修复。在工作中,首次应用了在六偏磷酸钠稀溶液中超声波清洗青铜器这一方法;对锌粉转化封闭有害锈方法进行了改进;选用ParaloidB-72材料做为青铜器苯骄三氮唑处理后的封护材料。这些技术方法与其它方法相配合,提高了工作效率,节约了药品,并取得了的显著的保护效果。  相似文献   
100.
Abstract

International heritage doctrine and the Operational Guidelines (OG) for the Implementation of the World Heritage (WH) Convention discourage the reconstruction of cultural heritage. Only ‘exceptional circumstances’ justify this practice, namely armed conflicts and natural disasters. The UNESCO WH Committee recently expressed its support for the reconstruction of damaged WH properties in view of such circumstances and requested the development of new guidance to address this timely issue (Decisions: 39 COM 7 and 40 COM 7). Guidelines will be prepared and provided to the Committee accordingly (Decision: 41 COM 7). We can therefore foresee revisions and additions to Paragraph 86, which is currently the only guideline in the OG, deemed ‘inadequate’ by the Committee. This research paper brings into focus the status of reconstruction in WH policy formulation and takes a normative position. Drawing on document analysis and the most up-to-date studies, I argue that its status should formally shift from exceptional case ruled out a priori to conservation treatment ruled in. I encourage a fruitful international exchange of ideas among a broad interdisciplinary readership to contribute to policy-making. Readers who dispute my position, no less than those who support it, may come to see reconstruction in a different light.  相似文献   
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