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1.
A procedure for deformation-controlled, or displacement-based, seismic design of multistorey RC buildings is proposed, implemented and applied for the full design of a four-storey RC structure. It is integrated into the overall structural design, along with the design for the non-seismic actions and consists of a ULS verification against the conventional strain limits for a frequent “serviceability” earthquake and of proportioning the compression reinforcement and the transverse reinforcement of critical regions of members to meet the member peak inelastic chord rotation demands under the “life-safety” seismic action. Quantitative rules and expressions are proposed for the estimation of (a) mean and upper-characteristic peak inelastic chord rotation demands, through appropriate linear-elastic analyses, and (b) mean and lower-characteristic values of member ultimate chord rotations, in terms of member geometric and material data.  相似文献   
2.
This article attempts to shed some light on the origins of Ptolemy’s map of the world, which remains a mystery. The premise is that Ptolemy and other ancient geographers largely drew on the same or a similar pool of sources and common beliefs. Similarities between them can, therefore, give us a key to understanding the prehistory of Ptolemy’s map. Comparison of distances on his map with those given by other sources leads to the conclusion that a large area of the map, approximately from the Bosporus to the Indus, reproduced Eratosthenes’ geographical system, with linear distances converted to angular degrees according to Eratosthenes’ own scale. It is argued that this area represents a remnant of an earlier version of Ptolemy’s map. Analysis of latitude and longitude reveals notable differences between Ptolemy’s map and Eratosthenes’ ideas concerning the latitude of Babylon and the Alexandrian prime meridian, and the impact this seems to have had on the shape of neighbouring regions is noted.  相似文献   
3.
Post‐mortem distortion resulting from the pressure of overlying sediments (i.e. grave backfill) is one of the taphonomic factors capable of altering the geometry of buried and subsequently recovered skeletal remains. If pressure distortion is a frequent occurrence, it could systematically flaw the outcome of an anthropological examination. To study the patterns of post‐mortem distortion in buried crania and shape alterations associated with a specimen's in situ position, 46 male crania recovered from an Old Slavic graveyard (Pohansko, Czech Republic) were analysed together with control specimens from four modern European osteological collections (N = 207) using geometric morphometrics. The results indicate a common pattern of shape change in buried skulls associated with their in situ orientation. However, as the overall shape variation between the Old Slavic crania (which, with their tendency towards longer, narrower shapes differed markedly from the modern Czech crania) oriented in situ on their back and side reflects the duality of dolichocranial and brachycranial forms, it seems likely that the in situ positioning of the crania stemmed from their original morphology. The lack of substantial effect of the in situ orientation on the cranial morphology is associated with a larger cranial size and a tendency for sturdiness in the Old Slavic subsample. Both of these characteristics are likely to be contributing to the resistance of these crania to taphonomic alterations. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
4.
Following the Malta Convention/Valletta Treaty the preferable way for the physical protection of archaeological sites is in situ preservation. When planning in situ preservation, in addition to other issues, it is also necessary to consider changes in physical environment and their impact on in situ preserved remains. This is especially important when human interaction takes place. Recently, an increase in construction on the top of archaeological sites has occurred, thus the effects of heavy equipment compaction need to be studied in more detail.

This paper presents research on the effects of the use of heavy equipment (e.g. rammers and rollers) compaction on archaeological remains. For the purpose of our research, laboratory testing has been performed. In a custom-made steel box, artificial archaeological sites were created using layers of sandy silt and gravel. A variety of archaeological and modern artefacts were placed in these created environments. Some of them were equipped with strain gauges for deformation recording. Through a series of tests a servo-hydraulic piston was used, which simulated the dynamic loading of the artificial sites. Humidity and temperature were recorded before, during, and after each test. Since layers and artefacts were three-dimensionally recorded before and after each test, compaction of layers and movements of artefacts could be studied. With attached strain gauges and visual inspection following each test, deformations and thus damage to artefacts during different stages of loadings was recorded.

The goals of our laboratory tests were the development of a new methodological approach to study the effects of heavy equipment compaction to the archaeological sites, getting an insight into the problems of such tests, and the estimation of the applicability of their results. With the presented results, our research has been a step towards better understanding the effects of heavy equipment compaction on archaeological remains and thus to the preservation of archaeological sites in situ.  相似文献   
5.
A coated Roman iron coin from Villa Loig in Salzburg, Austria was investigated. The coating is a copper alloy consisting of Cu, Pb, Sn, Zn and negligible amounts of Ag, a variant of gunmetal known as ‘leaded red brass’. The numismatic term for such a coin is subferratus (Latin). From an archaeometallurgical point of view, information about the chemical composition, the microstructure and the manufacturing technique are of interest. To achieve these objectives, different analytical techniques and metallographic examinations were applied. Droplet‐shaped iron inclusions were observed in the red brass coating, while at the grain boundaries, inside the iron core, copper and lead were detected (liquid metal embrittlement). The dendritic microstructure of the coating, the spheroidal‐shaped iron inclusions in the coating and the liquid metal embrittlement show that the iron coin was plated by immersing it in a molten copper alloy. The iron core is a low‐carbon steel with slag stringers, both of which are characteristic of a bloomery iron. Deformation twins (Neumann lines) were observed in the microstructure of the iron core and indicate that the coining was performed after the flan was cooled.  相似文献   
6.
Comparison of mass transfer patterns, geometry and microstructures developed within and around veins allows the interpretation of processes of fluid flow during deformation, metamorphism and mineralization. A classification of vein types based on the degree of interaction with wallrock (using petrological, geochemical or isotopic indicators) can be used to identify a range of processes, from closed system behaviour in which the vein mass is derived from local wallrock, through to open system behaviour in which the vein mass is derived externally. Microstructural characteristics, such as wallrock selvages, multiple growth events recorded by vein seams and vein crystal morphology, also help to constrain mass transfer patterns during vein formation. We present a range of processes for vein formation, including: (i) the formation of closed system fibrous veins by dissolution–precipitation creep, including varieties in which tensile failure is not required; (ii) pressure‐ or kinetically dependent closed system segregation veins in which transfer of soluble components from wallrock to vein leaves behind a residual selvage; (iii) similar vein–selvage patterning, but with mass imbalances between vein and wallrock requiring fluid advection through both interconnected fracture networks and in the surrounding permeable rock; and (iv) the proposed formation of veins by fluid ascent in mobile hydrofractures, in which isotopic or chemical disequilibrium within and around the vein suggests that the crack and fluid within it moved essentially as one. The postulate of rapid fluid and mass transfer via such mobile hydrofractures has implications for the release of volatiles from metamorphic terrains. Also, consideration of a broad range of possible vein‐forming mechanisms is highly desirable when dealing with mineral deposits found in deformed, metamorphosed rocks, because closed system veining may produce patterns that, if erroneously recognized as being open systems, could lead to false interpretations of the role of tectonic fracturing in ore genesis.  相似文献   
7.
If RC structural walls are properly designed and proportioned, these walls can behave in a ductile manner. To achieve this goal, the designer should provide adequate strength and deformation capacity of structural walls corresponding to each performance level (e.g. immediate occupancy, life safety and collapse prevention). This study investigates the drift and ductility capacities of T-shaped structural walls on the basis of results from experimental tests and sectional analyses. To determine proper deformation capacities for T-shaped structural walls, structural performances of T-shaped walls were evaluated with several parameters such as longitudinal reinforcement ratio, distribution of longi-tudinal reinforcement, lateral confinement ratio, and axial load ratio. Based on these results, the level of deformation capacity specified in current design provisions (ICBO, UBC 1997), which were expressed as both strain-based damage limit and interstorey drift ratio, were evaluated.  相似文献   
8.
An oil‐bearing sandstone unit within the Monterey Formation is exposed in the Los Angeles Basin along the Newport‐Inglewood fault zone in southern California. The unit preserves structures, some original fluids, and cements that record the local history of deformation, fluid flow, and cementation. The structures include two types of deformation bands, which are cut by later bitumen veins and sandstone dikes. The bands formed by dilation and by shear. Both types strike on average parallel to the Newport‐Inglewood fault zone (317°–332°) and show variable dip angles and directions. Generally the older deformation bands are shallow, and the younger bands are steep. The earlier set includes a type of deformation band not previously described in other field examples. These are thin, planar zones of oil 1–2 mm thick sandwiched between parallel, carbonate‐cemented, positively weathering ribs. All other deformation bands appear to be oil‐free. The undeformed sandstone matrix also contains some hydrocarbons. The oil‐cored bands formed largely in opening mode, similar to dilation bands. The oil‐cored bands differ from previously described dilation bands in the degree of carbonate cementation (up to 36% by volume) and in that some exhibit evidence for plane‐parallel shear during formation. Given the mostly oil‐free bands and oil‐rich matrix, deformation bands must have formed largely before the bulk of petroleum migration and acted as semi‐permeable baffles. Oil‐cored bands provide field evidence for early migration of oil into a potential reservoir rock. We infer a hydrofracture mechanism, probably from petroleum leaking out of a stratigraphically lower overpressured reservoir. The deformation bands described here provide a potential field example of a mechanism inferred for petroleum migration in modern systems such as in the Gulf of Mexico.  相似文献   
9.
This paper explores bioarchaeological evidence for cultural cranial modification (CCM; a.k.a. headshaping) in early Neolithic Near East and at Tepe Abdul Hosein (TAH), Iran, in particular. Skeletal remains from 12 Neolithic individuals (n  = 12) recovered from eight mortuary contexts were analysed for evidence of intentional CCM. The TAH remains are among the earliest Neolithic human skeletal remains in the world, dated to around 10 000 years ago. Five adult individuals have sufficient cranial remains to allow assessment of CCM. Of the remaining seven individuals, three are foetuses or perinates, for which no in vivo CCM was expected to be observed, two are subadults with no assessible cranial remains, and two adults have no associated cranial remains. Of the five adult individuals, which could be assessed for CCM, four display circumferential CCM, instigated by the use of two bands. Three are male, while the sex of the fourth cannot be estimated. The fifth individual displays no modification and is female. While all the modified individuals that can be sexed at TAH are male, the sample size is too small to draw extensive inferences as to the potential connection of CCM with any gendered sociocultural practices. Other possible motivations for CCM at TAH include elaboration of status differentiation or group affinity, the former of which can most likely be ruled out based on current understandings of early Neolithic societies in the region. The extent of the two‐band circumferential modification at TAH is significantly more pronounced than at Ganj Dareh, a contemporaneous site located within the same watershed. The discovery of different extents of headshaping within the same watershed, in relatively close proximity to each other, has a bearing on the understanding of the first sedentary Neolithic communities in southwest Asia and the elaboration of bodily difference and identity. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
10.
This study explores the changes in sinus and meningeal vessel patterns caused by various types of artificial cranial deformation. Endocranial casts were prepared from six crania exhibiting one of three types of deformation (lambdoid, parallelo-fronto-occipital and fronto-vertico-occipital), as well as from 15 undeformed crania. Vessel and sulcus patterns of each cranium were analysed and these patterns included depth of impressions, size and number of vessels, and directional pathways of vessels. Comparisons were made within and between the different deformation types. The results indicated that deformation has an effect upon the pattern, shape and depth of vessel impressions. Vessels tended to be flattened in the areas directly affected by cranial deformation, and there was often compensatory enlargement of other vessels. Further, three of the six artificially deformed crania exhibited enlarged occipital/marginal sinuses, suggesting that this trait is developmentally plastic and greatly influenced by environmental factors.  相似文献   
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