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31.
The ground penetrating radar (GPR) technique was used to investigate the subsurface in an urban area located in Mesagne (Italy) to obtain a map of the archaeological features in the ground. The GPR survey was undertaken at selected locations placed near (about 50 m) to a necropolis dating from the Messapian to the Roman imperial age, using a GSSI Sir System 2 incorporating 200 and 500 MHz centre frequency antennae. The selected areas (A and B) were surveyed along parallel 1 m spaced profiles using a 200 MHz antenna in area A and along parallel 0.5 m spaced profiles using a 500 MHz antenna in area B. For the selected areas the processed data were visualised in 3D space not only by means of the standard time slice technique, but also by means of a recently proposed approach, namely by iso-amplitude surfaces of the complex trace amplitude. The immediacy in revealing the spatial positioning of highly reflecting bodies, such as the anomaly interpreted as an old hypogeum room in area A, makes 3D visualisation techniques very attractive in archaeological applications of GPR. Their sensitivity to the signal/noise ratio is, on the other hand, highlighted by the quite poor performance in area B, where the only reliable result provided by all the techniques was the ancient living surface reflection, whereas none of them could effectively enhance the visibility of weak hyperbola reflections noted on 2D sections and probably related to the walls located on the ancient living surface. The performance of the various techniques in these two different situations allowed insights into their main advantages and drawbacks to be gained.  相似文献   
32.
The First Mallorcans: Prehistoric Colonization in the Western Mediterranean   总被引:1,自引:0,他引:1  
The paper aims to elucidate the first human colonization of the western Mediterranean island of Mallorca by answering such questions as: What was the cultural identity of the first archaeologically identifiable human settlers? What was the chronology of colonization? Where did the colonizers originate? And what were their contacts during the initial phase of settlement? It is based on recently acquired chronological data and on a review of the classical sources. A precise chronology for the first colonization event is proposed, supporting the idea that human settlement on Mallorca started within the period 2350–2150 cal BC. The coast of Languedoc, between the rivers Vidourle and Rhône, is the most probable source region. Whether the first settlers were derived from an Early Bronze Age or a Late Copper Age mainland culture remains unresolved. A rapid initial population growth following initial colonization is proposed. The available evidence points to the development of an essentially isolated population on Mallorca, developing an autochthonous culture with only limited contacts to mainland regions.  相似文献   
33.
A 3-D optical scanner was used to obtain precise and complete representations of lithic artifacts. A computer algorithm, which was specially developed for the purpose, was used to position the artifacts in a way which enables the extraction of the standard metric parameters (length, width, width at 1/2 length, etc.). In this way, the ambiguities which affect the traditional manual measurements were eliminated. This new methodology creates accurate and objective databases. Several other parameters (center of mass position, volume, surface area) were also computed. The advantages of our method are illustrated by the analysis of 90 scanned Lower Paleolithic handaxes.  相似文献   
34.
Optically stimulated luminescence (OSL) measurements are reported for single grains of quartz from deposits within Sibudu rock shelter. Such measurements enable rejection of unrepresentative grains and application of the finite mixture and central age models to obtain the most reliable age estimates. Three types of single-grain equivalent dose (De) distributions were observed: one sample represented a single dose population, three samples indicated mixing between Iron Age (IA) and Middle Stone Age (MSA) deposits, and 10 samples (in addition to the three mixed samples) showed scattered distributions. The latter type resulted from differences in the beta dose received by individual grains. For these samples, the beta doses were modelled and adjusted accordingly. Ages for the 14 samples collected from MSA deposits post-dating the Howiesons Poort (HP) resulted in three age clusters, which are stratigraphically consistent with the three informally named cultural phases at Sibudu: namely, the post-HP, late MSA and final MSA. Weighted mean ages of 58.5 ± 1.4 ka, 47.7 ± 1.4 ka and 38.6 ± 1.9 ka were calculated for these phases, respectively. The three phases were separated by two occupational hiatuses with durations of 10.8 ± 1.3 ka and 9.1 ± 3.6 ka. We hypothesise that the punctuated presence of humans at Sibudu was determined by large-scale fluctuations in climate during oxygen isotope stage (OIS) 3, which resulted in alternating wet and dry periods. Phases of occupation correspond to wet periods when fresh water was available in the Tongati River, whereas intervals of site abandonment correspond to dry periods when people were forced to migrate in search of a reliable source of fresh water. Where people migrated to, remains unresolved.  相似文献   
35.
The characterization of a ceremonial bronze axe is described. The axe is assigned to the Santamarian culture of north‐west Argentina, c. 1000–1470 ad, and was selected to increase presently limited knowledge of prehistoric metallurgy in the Andean region of Argentina. The characterization methods used were electron probe microanalysis, gamma radiography, X‐ray diffraction, optical metallography and microhardness testing. The axe was well cast in a bivalve mould, with the only defects in the area of an ancient fracture. The analysis showed that it is made from a tin bronze with a, probably, accidental addition of lead. Arsenic was found as a surface contamination, probably deriving from arsenic in the water of the stream in which the axe was found. The axe shows that Santamarian craftsmen had the skill to decorate the axe in an artistic style with a strong local accent while providing a functional, annealed and cold‐worked cutting edge.  相似文献   
36.
Satellite radio posed a new question for Canadian policy-makers: How to take advantage of a transnational radio service while ensuring cultural identity was not lost within channel offerings that are predominately American. Comparing the initial licensing of satellite radio in Canada (2005) to the merger of the services (2011) and the post-merger license renewal (2012) highlights a shift in the spatial understanding of satellite radio, from being determined by a satellite’s footprint to that of what I call ‘cultural lifelines,’ the various mobile devices and services that enable one to maintain connection to cultural content. Alongside shifting spatial considerations of satellite radio, Canadian content has increasingly been packaged as a brand or genre, catering to fragmented taste preferences and individual, mobile listening practices.  相似文献   
37.
Knowledge of Sicilian biology during the past is very important in understanding the complex processes that characterized the population of the Mediterranean Basin. The problem of the first Greek settlement in Sicily is essential in understanding and reconstructing the indigenous biological tissue of an island that was and still is a fundamental crossroads for migratory strategies. In this research we studied ten Sicilian series chronologically attributed to the second and first millennium BC , using discrete cranial traits. The results show that the first biologically significant Greek presence in eastern Sicily could go back to the Bronze Age, while the cosmopolitan Hellenistic city of Syracuse showed the nature of the biological pattern during the first millennium BC . Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
38.
景德镇御窑遗址出土的15世纪中叶青花方胜纹绣墩,体量较大,器形特殊,出土时破损和缺失严重,修复难度较大。本研究通过分析传统考古修复中石膏作为补配材料的局限性,利用3D扫描打印的优势,设计采用新颖的高强度透明树脂取代传统修复补缺材料,并且结合特制的加固装置完成对大型青花绣墩的考古修复,满足了后期研究与展览的需要。本研究提出了具有一定实践意义的3D打印补配大件异形陶瓷器的修复技术路线。  相似文献   
39.
杜美龄  孙根年 《人文地理》2015,30(2):155-160
经济全球化背景下,国际"贸易-交通-旅游"(3T)互动日益增强。采用1982-2011年时间序列数据,分析国际贸易、交通和旅游总量的发展历程,从进、出口分量视角考察三者相关关系,运用最小二乘法构建回归方程。结果发现:①30年来国际贸易、交通和旅游的发展呈持续增长态势。国际贸易和旅游日益重要。②国际贸易、交通和旅游增长过程具有同步性,表现为波动周期同涨同落。③所构建的回归方程决断系数R2均在0.99以上,国际贸易、交通和旅游存在显著相关性。国际货运与国际贸易,国际客运与国际旅游之间具有确定、直接的因果关系;国际贸易与国际旅游的因果性尚待探究。  相似文献   
40.
In this paper, the characterization of Roman amphorae from the Porto dos Cacos (PC) and Quinta do Rouxinol (QR) workshops, in the Tagus estuary, dating to a period between the 1st and 5th century AD was carried out on the basis of instrumental neutron activation analysis data on 260 amphorae fragments, together with mineralogical compositional studies obtained by X-ray diffraction.  相似文献   
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