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81.
An optimization method based on uniform damage distribution is used to find optimum design load distribution for seismic design of regular and irregular shear-buildings to achieve minimum structural damage. By using 75 synthetic spectrum-compatible earthquakes, optimum design load distributions are obtained for different performance targets, dynamic characteristics, and site soil classifications. For the same structural weight, optimum designed buildings experience up to 40% less global damage compared to code-based designed buildings. A new general load distribution equation is presented for optimum performance-based seismic design of structures which leads to a more efficient use of structural materials and better seismic performance. 相似文献
82.
为综合研究出土玉器的风化机理,正确评估玉器的保存状况,本研究采用物相、成分和电镜等方法对2016年广州重要考古发现——增城墨依山玉器进行了材质和结构分析,确认了墨依山玉器材质为透闪石。在此基础上,对玉器周边土壤进行了物相、成分、结构和酸碱度等分析,并结合玉器本体和遗址气候条件,综合探讨了强酸性环境下墨依山玉器的受沁过程。本研究有助于丰富对玉器风化机理的认识,有利于科学制定玉器的保护措施。 相似文献
83.
R. M. Prothero 《Scottish Geographical Journal》2013,129(1):44-54
The relevance to Political Geography, and the nature of the recent electoral emergence of Welsh and Scottish nationalism are examined. Contrasts in geographical conditions associated with the performances of the Welsh and Scottish parties are found to be related to their ideological and cultural characters. The Scottish National Party appears primarily a vehicle for protest, whereas Plaid Cymru is more an expression of a threatened culture. 相似文献
84.
Early maps of Scotland at a national scale provide historical geographers with an important source of data. One of the most important of these maps but still relatively unexploited and poorly understood is the Military Survey of Scotland or Roy Map. Examination is made here of its two versions, the Protracted Copy and the Fair Copy, to check the veracity of the draughtsmen who produced the latter and most commonly consulted version. An examination is made by focussing on two areas of Fife. 相似文献
85.
T.P. Taylor 《Journal of archaeological science》1979,6(1):93-100
The fate of artifacts incorporated into the ploughsoil as a result of plough damage is considered in terms of two soil mark sites near Winchester, Hampshire. Ploughsoil and subsoil analyses indicate that dispersal of soil material, as a result of ploughing, is limited at the present time and under mould board ploughing techniques. The origin of soil marks underlain only by bedrock is also considered and evidence indicates that such soil marks may appear as groundsurface expressions of ditches which have been removed by plough damage where dispersal of ploughsoil is minimal. Such soil marks may be only short lived if plough depth continues to increase. 相似文献
86.
V. Bartůněk K. Dobrovolný M. Švecová P. Matějka P. Šída P. Pokorný M. Kuchař E. Černá 《Archaeometry》2017,59(2):346-355
In this study, we present a novel, safe method for how to remove inorganic components from soil samples studied for archaeological purposes, in order to improve studies of the distribution of black carbon in the sedimentary record. As the depositional history of this material depends on the interaction between humans and the natural environment, this method can be widely used in archaeology, landscape archaeology, palaeoecology, environmental geology and sedimentology. Our method does not require the use of dangerous hydrofluoric acid, which is commonly used for the removal of silicon oxide from such samples; therefore, this procedure allows even less chemically trained scientists to analyse soil samples with an increased level of work safety. 相似文献
87.
S. P. Maslin 《Environmental Archaeology》2018,23(2):137-151
Palaeoecological and geoarchaeological investigations which cover the Anglo-Saxon period are rare, particularly in chalk downland landscapes which are considered to have limited palaeoenvironmental potential. The present study explores a sequence which can be directly related to the occupation history of the major Anglo-Saxon settlement at Lyminge, Kent. This work demonstrated a sequence of palaeochannels and organic deposits associated with the latter part of an archaeological sequence which spans the 5th to the 11th centuries AD. A range of evidence for the environment and economic activity is presented which suggests landscape continuity, possibly stretching back as far as the Romano-British period. The sequence revealed worked wood and evidence for livestock management and cereal cultivation, some of which is contemporary with the final phases of occupation of a 7th century ‘great hall complex’ and its subsequent transformation into a royal monastery. Agricultural activity following the abandonment of the pre-monastic settlement area caused this stream margin to become gradually buried by ploughwash which displaced the channel over time and sealed the organic deposits. It is incredibly rare to find such organic preservation in direct association with an Anglo-Saxon downland rural settlement and this is the first time that such a sequence has been analysed in association with the latter phases of a known Anglo-Saxon royal and monastic centre. 相似文献
88.
Liangcai He Tarek Abdoun Akio Abe Ricardo Dobry Masanori Hamada 《Journal of Earthquake Engineering》2013,17(7):916-938
One-g shake-table experiments are conducted to explore the response of single piles due to liquefaction-induced lateral soil flow. The piles are embedded in saturated Medium Relative Density (Dr) sand strata 1.7–5.0 m in thickness. Peak lateral pile displacements and bending moments are recorded and analyzed by uniform and triangular pressure distributions. On this basis, the observed levels of pile bending moment upon liquefaction suggest a hydrostatic lateral pressure approximately equal to that due to the total overburden stress. Using the experimental data, comparisons with current recommendations are made, and the Showa Bridge case history is briefly assessed. 相似文献
89.
Phosphorus analysis of earthen and plaster floors has been used in Mesoamerica to locate and identify activities at ancient sites. This study uses phosphorus analysis to discern if the inhabitants of two Late Classic coeval and proximal sites located in the El Paraíso Valley of Honduras were different culturally from each other. The buried earthen and plaster surfaces of both sites were systematically sampled and analyzed for phosphorus remains. The patterns of elevated phosphorus from these open spaces were subsequently compared to determine if differences in the habitual use and treatment of open spaces could be discerned. These differences are evaluated as a function of behavioral norms, functional responses, and cultural dispositions in order to evaluate the extent to which these two populations were indeed different from each other. 相似文献
90.
The absolute chronology of the agricultural soil from organic matter has always been difficult to measure due to several reasons. In our work on the Prehispanic agriculture in the Calchaqui Valley – Argentina, however, an absolute chronology is necessary to distinguish the Inca prevalence of the previous agricultural structure. Instead of looking for a new dating methodology, we have used the 14C method trying to eliminate the error sources typical of soils. Thus, we have dated new types of agricultural structures, with the assumption that they would have worked as archaeological “seals”. In the present paper we show that the dating of the beginning of the use of the Prehispanic agricultural systems has been successful. 相似文献