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51.
A prototype diesel generator equipped with a vibration isolation system consisting of restrained isolators (denoted as I/system) is quasi-statically and dynamically tested. Sequentially, the seismic simulation tests are conducted to further investigate the effectiveness of additional snubbers incorporated into the vibration isolation system (denoted as I/R system). Comparing the test results to the static design demands specified in ASCE 7-10, the recommended component amplification factor could represent the horizontal acceleration amplification phenomenon of the generator equipped with I/R system; however, the seismic force demands for static design of I/R system might not be appropriate and conservative enough.  相似文献   
52.
The Middle Paleolithic industry of the Sibiryachikha facies is described on the basis of two stratified sites in the Altai – Okladnikov Cave (formerly Sibiryachikha) and Chagyrskaya Cave. Stratigrtraphic, environmental, and chronological aspects are discussed. The structure of two cave sites is analyzed. Petrographic properties of raw material are described and the typology and technology of the lithic industry are compared with those of other local Middle Paleolithic traditions. The Sibiryachikha facies of the Altai Middle Paleolithic represented by two sites was clearly associated with a small group of Neanderthals who migrated from western Central Asia. Eventually the Middle Paleolithic industry evolved into a local variant of the Upper Paleolithic.  相似文献   
53.
Between about 500 a.d. and the late nineteenth century, clay cooking pots associated with the Thule culture were produced in the Arctic region. Ethnographic and archaeological records indicate that these vessels were typically underfired (often even unfired), highly porous, and easily broken. Despite these characteristics, the evidence indicates that they were used to heat water over open fires. In this paper, we examine how Arctic potters were able to produce unsintered vessels capable of holding liquids without disintegrating. We conclude that the application of seal oil and seal blood to the pot’s surface was the key to their success.
Karen G. HarryEmail:
  相似文献   
54.
The identification of projectile impact traces on archaeological faunal remains is an important issue for understanding prehistoric hunting behavior, especially in the Paleolithic and Mesolithic. From the beginning of the Upper Paleolithic in Europe, and earlier in Africa, projectiles tipped with osseous points were of great importance for subsistence; but thus far, no specific experimental reference has been developed to help identify the traces left by these points. In 2003 and 2004 two series of projectile experiments with antler points of Magdalenian design were organized, involving two ox calves and two female fallow deer as targets for bow and spearthrower shooting. The subsequent study demonstrates that positive identifications of impact traces left by osseous points can be made. The observation of 127 impact traces allowed us to distinguish three main types of traces: notches, punctures and perforations. The relationships between the nature of the impact traces and the (i) target species, (ii) characteristics of the impacted bones, and (iii) type of weapon are presented. Synthesized results are then discussed within the context of the European Upper Paleolithic and Mesolithic.  相似文献   
55.
Conditions in which thermal fractures occur are explored experimentally, and the results are used to assess heat treatment strategies. We conclude that no single ‘critical temperature’ for thermal fracturing or heat treatment can be specified for any particular raw material, as has so often been attempted, because threshold temperatures exist in relationship to specimen sizes. Our experiments show that smaller specimens are resilient to greater ranges of temperature fluctuations than larger ones, and that by manufacturing/selecting specimens of smaller sizes there is more potential to heat them rapidly and to higher temperatures without producing thermal fractures. We hypothesize a continuum of heat treating strategies between a ‘slow and steady’ strategy, which has overwhelmingly dominated past experimental designs, and a ‘fast’ strategy, which has received much less attention. The paper discusses the economic and technological contexts to which different heat treating strategies might be suited.  相似文献   
56.
For many decades the use of backed pieces from the Howiesons Poort, between about 70 ka and 55 ka ago, in South Africa has been a point of discussion. Recently direct evidence has been provided to associate these tools with Middle Stone Age hunting strategies. Yet, whether they were used to tip hunting weapons or as barbs remained an open question. In this paper we introduce a set of pilot experiments designed to test the effectiveness of Howiesons Poort segments, the type fossils of the industry, hafted in four different configurations as tips for hunting weapons. It is shown that the morphological type can be used successfully in this way. We present the results of a macrofracture analysis conducted on the experimental tools and compare these to results obtained from three Howiesons Poort backed tool samples. By correlating experimental outcomes, macrofracture data and the interpretation of micro-residue distribution patterns, we provide some insight into the functional variables that might be associated with Howiesons Poort segments.  相似文献   
57.
丁秀萍 《攀登》2008,27(5):96-99
农村新型合作医疗制度,是由政府组织、引导和支持农民自愿参加,由个人、集体和政府多方筹资并以大病统筹为主的农民医疗互助共济制度。为了更加有效地解决农民“看病难、看病贵”问题,西宁市政府应积极履行社会管理和公共服务职能,切实建立农村新型合作医疗科学高效的筹资机制、运行机制、监督机制和规范机制。  相似文献   
58.
This paper presents the results of a microscopic analysis conducted on supposedly retouched glass fragments that were likely used as tools. The pieces were recovered in a series of excavations performed at the historical site of Fortlet Miñana (1860–1869), a military settlement used during the war against the Indians on the southern border of Buenos Aires province, Argentina. The use of glass as raw material in archaeological sites of the historic period has frequently been reported in the Pampas and Patagonian regions. In this paper we present a review of ethnohistoric and ethnographic sources concerning the use of glass side scrapers, end scrapers, and arrowheads by aboriginal groups throughout the world. In order to perform the analysis, the glass fragments from Fortlet Miñana were compared to a series of experimental pieces on which traces of deliberate use on two kinds of raw material, wood and hide, were identified. The experimental approach and the microscopic analysis demonstrate that the retouched glass fragments recovered at Fortlet Miñana were not used as tools. Therefore, we conclude that microscopic analysis is of significant use to all researchers working with materials of this kind.  相似文献   
59.
Significant amounts of opercular bones from Cyprinus carpio, used to manufacture circular pearls for adornments, were found from the Romanian Eneolithic, associated with the Gumelnita culture. The origins of this raw material are local: the carp was an important food resource for the communities located close to the River Danube. An experimental program was undertaken to obtain replicas of pearls of C. carpio, to compare with the archaeological pieces, in order to identify an a chain of manufacture resulting in the finished pieces. The study of the adornments represents an inexhaustible source of reflection because, through them we can identify aspects of the human groups' symbolical behaviour, and socio-economical aspects of these communities' evolution. In this case they suggest that the aquatic world, with its resources, had an important position in the spiritual life of these communities.  相似文献   
60.
T. J. Booth 《Archaeometry》2016,58(3):484-499
A central problem in funerary archaeology is interpreting how the corpse was manipulated in the immediate post mortem period. The extent of bacterial bioerosion to the internal bone microstructure has been proposed as a means to infer the early post mortem history of a corpse, as it has been suggested that this form of bone diagenesis is produced by an organism's putrefactive gut bacteria. Under this model, different forms of funerary treatment would be expected to leave characteristic signatures of bioerosion in archaeological bone. Here, we tested the extent to which bacterial bioerosion of ancient human bones reflected funerary treatment, through histological analysis of 301 archaeological human bone thin sections from 25 European archaeological sites. We found that bioerosion was significantly influenced by whether a bone originated from a neonatal individual or an anoxic context. When these remains were excluded, bioerosion was controlled by archaeological phase in a manner consistent with known early post mortem treatment and forensic models of bodily decomposition. These findings suggest that microscopic analyses of bone have useful applications in reconstructions of funerary processes and provide some insight into factors that may control the persistence of organic biomolecules and fossilization.  相似文献   
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