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1.
Recent fieldwork has considerably increased our knowledge of early Holocene settlement in Southwest Arabia. Neolithic settlement occurred within an environmental context of increased monsoonal moisture that continued during the mid-Holocene. A now well-attested Bronze Age exemplified by village- and town-scale settlements occupied by sedentary farmers developed toward the end of the mid-Holocene moist interval. The high plateau of Yemen was an early focus for the development of Bronze Age complex society, the economy of which relied upon terraced rain-fed and runoff agriculture. On the fringes of the Arabian desert, the precursors of the Sabaean literate civilization have been traced back to between 3600 and 2800 B.P., and even earlier, so that a virtually continuous archaeological record can now be described for parts of Yemen. In contrast to the highlands these societies relied upon food production from large-scale irrigation systems dependent upon capricious wadi floods. Bronze Age settlement, while showing some links with the southern Levant, now shows equal or stronger linkages with the Horn of Africa across the Red Sea. Although some regions of Yemen show breaks in occupation, others show continuity into the Sabaean period when a series of major towns grew up in response to the incense trade with the north. It is now clear that these civilizations grew up on the foundations of earlier Bronze Age complex societies.  相似文献   
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明代中后期,闵行镇凭借其便利的交通条件与繁荣的棉花种植业,成为上海县重要的商业市镇。近代以来,随着上海城市的发展,闵行镇与上海城区间经济联系不断密切,政治地位也日趋重要。新中国成立初期,优先发展重工业的国家政策与华东沿海地区的战略地位,使得民国时期奠定重工业基础的闵行镇备受各方重视。在国家政策、经济体制、地方利益等因素的综合作用下,闵行镇最终由江苏省上海县划归上海市。  相似文献   
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苏小东 《安徽史学》2007,(1):99-105
刘铭传以武将而跻身于封疆大吏之列,其一生之建树重在“事功”而非“理论”。正因为如此,他虽然也曾就海防及其相关问题有过全面系统的论说,但其认识水平显然不及同时代之佼佼者。关于台湾在中国海防中的战略地位,他也是在领导抗法保台、建台的过程中逐步加深认识的,并以首任台湾巡抚之地位不遗余力地将其思想主张付诸实践,开创了包括海防在内的台湾近代化新局面。刘铭传加速台湾建设、加强台湾海防的初衷是为了抵御日本的侵略,不料数年之后,台湾竞因北洋海防的崩溃而落入日本之手。这绝不是刘铭传个人的悲哀,实乃国家民族之大悲剧。  相似文献   
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The Hui-style residence is an important architectural heritage of China. The hollow wall structures are widely used to build its exterior wall system. However, the thermal performance of the hollow wall is no longer able to meet the new energy-saving and environmental requirement. This article describes a laboratory study of the development of foamed mortar (FM), with the potential for use in thermal upgrading of the Hui-style hollow wall system without dramatically changing its traditional structure. The key early age, physical, mechanical and thermal properties were systematically measured. Two extended models were respectively developed to calculate compressive strength and thermal conductivity, as a function of porosity. Environment chamber test was also employed to investigate the effectiveness of this novel thermal upgrading approach and the results show that filling the voids with FM can effectively improve the overall thermal resistance of the hollow wall system by 44%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system. In addition, the combination of these two methods yielded an overall thermal resistance of 0.701 m2·K/W, which is even higher than 0.67 m2·K/W for the code required in the hot summer/cold winter climate zone.  相似文献   
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In this paper, we argue that place mapping is useful for approaching children's conception of place and that this is of relevance when designing physical activity interventions. We contend that socio-material factors influence children's perception and use of places, and are crucial to understand in relation to their use of local neighbourhoods for physical activity. A place mapping of children's understandings and everyday use of their local neighbourhood in suburban Copenhagen was conducted with a fifth grade elementary school class. The mapping and subsequent analysis resulted in three categories of relevance to children's conceptions of place; located social experiences, experiences of the unknown, and children's contested spaces. We argue that such knowledge can provide useful information in the development and evaluation of activities that promote physical activity in urban spaces.  相似文献   
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In 2000, a well‐preserved, c.21 m‐long shipwreck, Doel 1, was found upside‐down in a silted‐up creek near the river Scheldt (Belgium). An interdisciplinary research project was initiated, including 3D registration of all timbers, wood species identification, dendrochronology and archaeobotanical analysis of the caulking material. Doel 1, of which 70% is preserved, displays the construction features of a cog. Unseasoned wood was used and dated by dendrochronology to AD 1325/26. Remarkable features include the symmetrical layout of the bottom planks, the atypical arrangement of the frames to the fore, and evidence of partial dissassembly of the ship after intensive use.  相似文献   
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Metallurgical analyses and chemical characterizations were carried out on historical cannonballs from the Fortress of San Juan de Ulúa, Veracruz, México. Cannonballs dating from the 18th and 19th centuries share metallurgical characteristics similar to those of material coming from a shipment of ammunition found in the wreck of a sunken French ship from the battle of Trafalgar. The analyses show that the base material is grey cast iron with a carbon equivalent of 4.94 and a ferritic–perlitic matrix, in which the high phosphorus content has led to the formation of iron phosphide compounds in conjunction with a homogeneous distribution of carbon graphite flakes of Type C. In addition, corrosion products from samples revealed the presence of various crystalline iron compounds (X‐ray diffraction), mostly highly chlorinated iron compounds identified as akaganeite. X‐ray fluorescence identified various characteristics of the corrosion products as a function of the sampling depth. FT–IR spectroscopy revealed that the main difference between the corrosion products (internal and external) is determined by the number of organic species. Differential scanning calorimetry corroborated that these corrosion products are thermally stable compounds at elevated temperatures.  相似文献   
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This paper investigates the context of student learning in study abroad programs, drawing on ethnographic research on a semester long study abroad program in South India. We show how students use multiple constructions of time and space as a framework for understanding cultural differences and for understanding what it means for them to “experience” India. We argue that students' conceptualization of space and time in the study abroad location also impacts what kinds of activities they consider to count as valuable forms of learning. Students' ideas about India shape their expectations of what the pace, workload, and activities of the study abroad program in India should entail. Their concepts of Indian time and space lead them to privilege “experience”-based learning over classroom-based or scholarship-based learning. In conclusion, we show how these insights have implications for study abroad pedagogy. Here, we suggest that student learning that is entirely based on “experience” outside the classroom is inherently limited and that students need to contextualize their field-based learning experiences with insights from critical, historical and social science research.  相似文献   
10.
The advertising of unhealthy food and beverages forms an important component of obesogenic environments. Such marketing to children is a key health determinant because of its impact on dietary preference and food purchasing behaviour. The location of outdoor advertising is important in exploring obesogenic environments and children's neighbourhoods. The aim of this study is to explore issues involved in the use of Google Street View to examine outdoor food and beverage advertising. The implications for using Google Street View in the context of neighbourhood built environment research and grass‐roots advocacy are discussed. The study was conducted within walkable distances from 19 primary and intermediate schools in Auckland, New Zealand, where “walkable” was defined as limited by 800 m road network boundaries, which are equivalent to school buffer boundaries. Google Street View allows for centrality of data collection, coding, and storage. However, challenges exist with the method because 727 (29.4%) of a total of 2,474 outdoor advertisements that were identified were not able to be categorised because images were unclear, not in English, blocked, or at angles where detail cannot be deciphered. Specific to outdoor advertising for food and beverages, the results presented here show that children are exposed to a significantly greater number of unhealthy advertising than other advertising, P=0.001, eta‐squared statistic (0.45) indicates a large effect size. Overall, the results show promise for the use of Google Street View in the study of obesogenic environments.  相似文献   
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