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141.
Microzonation is widely used in seismic risk evaluations to define the predominant period values, which are usually associated with extended areas of a few hundred meters. However, the representative values corresponding to these areas are obtained from few measurements in each area. Thereby, results are accurate only in the case of depth-dependent soils. However, not detected narrow and sharp lateral changes in soil are potentially the cause of imprecision and could be a source of specific errors. This article aims to present several tests conducted in order to emphasise the importance of accurate selection of points, to underscore the necessity of more precise and detailed evaluations, and to suggest a possible methodology to select the most appropriate data acquisition points. Results highlight the need to divide microzonation areas into smaller zones for a precise evaluation in locations where sudden changes in soil characteristics exist. Therefore, in such sites the requirement of nanozonation appears; defining zones with the same soil response. Distance between vibration measurements could be the main problem for nanozonation; data acquisition in areas with irregular geology can be time consuming when a precise analysis is required. In the most complicated environments or in dense cities, it could even be unfeasible. Consequently, it is necessary to establish a functional methodology to adequately distribute the measurement points throughout the area. On this occasion, three sites in Barcelona city were studied. This city is surrounded by mountains at NW, W, and S, and by the Mediterranean Sea at N and E. As a consequence, the shallow geology is characterized by many paleochannels and streams that are currently buried. These geological structures most likely affect the soil response. Several tests were carried out to determine this dependence. The tests were based on Ground Penetrating Radar (GPR) surveys to define the paleochannels position and on vibration measurements in order to define properly the soil response. The results from both methods were compared to the known geology to accurately define the effect of the shallow geological structures in the predominant period and in the GPR images. Areas with the same geological unit but different materials were identified in the GPR images, allowing the selection of the most appropriate distance between vibration measurements in each place. As a final result, predominant periods that were measured over the same geological unit but over different material showed changes higher than the 40% in short distances. This procedure could improve the soil response maps, including nanozonation.  相似文献   
142.
Traditional timber frame walls are constructive elements representative of different timber frame buildings, well known as efficient seismic-resistant structures. They were adopted as a seismic-resistant solution in Lisbon’s reconstruction after the 1755 earthquake. To preserve these structures, a better knowledge of their seismic behavior is important and can give indications about possible retrofitting techniques. This article provides a study on possible retrofitting techniques adopting traditional solutions (bolts and steel plates). Static cyclic tests were performed on retrofitted traditional timber frame walls. The experimental results showed the overall good seismic performance of steel plates and the more ductile behavior of bolts retrofitting.  相似文献   
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This paper provides a new, interpretive gazetteer and chronology of Hadramawt’s highland monuments based on results from archaeological survey and test excavations by the RASA‐AHSD (Roots of Agriculture in southern Arabia‐Arabian Human Social Dynamics) Project. With the exception of a few incidental sightings and an unpublished pipeline survey, the prehistoric record of southern Yemen’s highland plateau has been largely unknown. There are few settlements, so that understanding human landscape history must begin with the numerous small‐scale stone monuments left by mobile people. With examples representing monuments from the fifth, fourth, third and first millennia BC, the corpus of small excavations and radiocarbon dates reported here provides the first guide to the monument types of South Arabian highlands. Monument building began under more moist conditions and appears to have commemorated animal sacrifices long before commemorating mortuary rites and interment. There appears to be a temporal break of 1000 years before the widespread and varied practices of Bronze Age tomb construction, which lasted through the third millennium BC. After another break in monument construction, tombs were reused in the first millennium BC, sometimes with successive ritual visits. The data presented offer new material for the interpretation of the lives and activities of prehistoric pastoralists throughout the Holocene.  相似文献   
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Many models have been proposed to explain both the rapidity of China's fertility decline after the 1960s and the differential timing of the decline in different places. In particular, scholars argue over whether deliberate policies of fertility control, institutional changes, or general modernization factors contribute most to changes in fertility behavior. Here the authors adopt an ethnographically grounded behavioral-institutional approach to analyze qualitative and quantitative data from three different rural settings: Xiaoshan County in Zhejiang (East China), Ci County in Hebei, (North China), and Yingde County in Guangdong (South China). The authors show that no one set of factors explain differential timing by a combination of differences in social-cultural environments (e.g. spread of education, reproductive ideologies, and gender relations) and politico-economic conditions (e.g. economic development, birth planning campaigns, and collective systems of labor organization) during the early phases of the fertility decline.  相似文献   
147.
During the 2013 fieldwork of the French archaeological mission along the shores of the Arabian Sea, mancala games were discovered on the seashore of Salalah at the site of Ad‐Dahariz. They are cup‐hole carvings made directly into rock slabs and distributed in six distinct zones of the site. They usually consist of fourteen cup‐holes aligned in two lines of seven, two supplementary holes being sometimes present on each side. They are the first of their kind in South Arabia and can be compared to similar configurations of carved games elsewhere in Arabia, such as at Jebel al‐Jassasiya, Qatar. This paper presents the potential origins of this game in the region, as well as a plausible dating of their use.  相似文献   
148.
Material from the Jindingshan Formation (Tsanglangpu stage) at Jindingshan, Guizhou province, China, confirms that Agastrocyathus grandis Yuan & Zhang is a massive compound archaeocyath with chaetetide architecture. A new genus Zunyicyathus includes this species and Z. pianovskajae from Central Asia.  相似文献   
149.
The site of U?urlu on the island of Gökçeada (Imbros) is the earliest known Neolithic settlement within the Aegean Islands (c.6800–4500 cal. BC). In total, 37 pits, associated with a rich variety of artefacts as well as human and animal bones were excavated in the Late Neolithic and Early Chalcolithic levels of the site (c.5900–4500 BC). The pits belonging to the early sixth millennium BC levels of U?urlu were small and located within the houses that seem to have gone through multiple episodes of house destruction and renovation rituals. During the late sixth millennium BC, this area became the focus of extensive pit‐digging activity, when large pits involving rich variety of artefacts were set within the courtyard of a special building (Building 4). Among the pits, a collective human burial pit (P188) incorporating the remains of 11 individuals and another pit (P52) involving a partial human skeleton were also found. From a comparative point of view, the construction techniques of these pits, their spatio‐temporal relations as well as their associated archaeological artefacts resemble the Anatolian and Near Eastern Neolithic practices of house destruction and renovation cycles, which are activities related to the ancestor cults of the region. We argue that all of these practices reflect public events during which social relations were negotiated through the agency of place. The differences observed during the sixth millennium BC at U?urlu reflect the changing concepts of place and society in the immediate aftermath of the Neolithic Process, when interactions with the Balkans as well as the Aegean intensified in this region.  相似文献   
150.
Josephine Baker and Anna May Wong are two exceptions to white hegemony in early show business. They became the first Afro-American and Chinese-American stars in the 1920s and reached international stardom in spite of their ethnicity but also because of it. Their careers and success were based on their exoticization. Baker and Wong's exoticism has much to do with ethnicity, but also with sex and gender. Their exotic dances on stage or on screen can be considered to be forms of erotic shows. This article shows how sex, gender, and race are entangled in their movies and burlesque shows. It also discusses the ways in which the agency and the audience of the performer should be taken into account, and analyzes how these performances were both rooted in Western imaginative geographies and connected to symbolic and material spaces.  相似文献   
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