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1.
近年来,随着我国港口资源整合、港区功能调整和港口城市的转型升级,沿海港口与所在城市的关系发展面临新的变化和挑战。本文以我国沿海港口为例,结合定量分析与定性讨论,聚焦我国沿海港口港城关系问题,剖析港城关系的演变及驱动机制。研究发现:我国大部分沿海港口已进入极度协调发展阶段,但发展趋势逐渐放缓,区域分化特征显著,港城协同度差距呈现再扩大的发展趋势。在研究期间,我国城市驱动型港口城市数量显著增加,港口驱动型和港城互驱型港口城市数量减少。建议通过政府政策引导、港产城融合发展和港口转型升级等方式,不断提升我国沿海地区港城关系整体协调发展水平,为新时期我国沿海港口与所在城市的高质量发展提供重要支撑。  相似文献   
2.
The Pacific Coast of North America was occupied by many distinctive groups of coastal hunter-gatherers at the times of early contacts with Europeans. Despite significant cultural diversity, Pacific Coast peoples shared lifeways oriented toward generally similar marine, nearshore, littoral, and estuarine habitats. In this paper, we examine some major issues that guide much of the archaeology done along the Pacific Coast, then discuss some of the theoretical and methodological problems that limit the efficacy of archaeological reconstructions. Most archaeological research conducted on North America's Pacific Coast has been oriented toward the search for the origins and development of a variety of cultural patterns. A comparative review of California and Northwest Coast sequences provides interesting parallels and discrepancies in the approaches taken in studying some of the major issues in Pacific Coast prehistory.  相似文献   
3.
ABSTRACT

Climate change impacts will increase in their frequency and severity in the coming decades, resulting in compromised integrity or destruction of thousands of heritage resources. Efforts are needed to identify, record, and study resources that will be affected. To set research and preservation priorities, the vulnerability of resources to climate change impacts and their importance to scientific research, preservation, and other resource values needs to be understood. We advocate a modelling approach which predicts the location, timing, and severity of climate change impacts; identifies resources at risk, their resource values, and opportunity costs; and prioritises research and preservation options based on these assessments. The need for this approach is illustrated with examples from two coastal areas subject to different impacts and hosting different types of heritage resources: the Atlantic coast of Georgia in the United States and the Wismar Bight along the Baltic Sea in northern Germany.  相似文献   
4.
The seismic vulnerability of city centers is commonly assessed by extending the study methods applied to single buildings to urban aggregations. This approach is not always applicable at territorial scale, as it is uneconomical in terms of time and costs. An innovative method provides reasonable large-scale a priori estimation of parameters not directly evaluable from the exterior of buildings by elaborating values which can be measured from the outside. Those parameters are treated as continuous variables, by assigning them a suitable probability density function. The Bayesian approach is adopted, which allows the update of initial hypotheses by using new data gathered during on-site surveys. In this regard, a rapid survey form for the on-site data collection is proposed. An example of its application to a façade of a building structural unit in Santo Stefano di Sessanio in L’Aquila province (Italy) is proposed, showing promising preliminary results for buildings belonging to Italian historical centers.  相似文献   
5.
This commentary considers an often overlooked contribution to food security in Australia—the labour of working holiday makers. Their ability to act as a flexible and mobile temporary workforce is essential to the maintenance of the Australian agricultural industry. Previously, no tax was payable on income below $18,200, but a 2015 proposal to increase their tax rate sparked a vigorous political debate and so revealed their importance to the agricultural industry. A decline in backpacker numbers would cause agriculture to shrink to cope with smaller workforces. But the effects of climate change are expected to further shrink agricultural areas as extreme events and hotter temperatures impact crops, livestock, and the productivity of agricultural workers. Issues that appear manageable when viewed in isolation, such as increases in the tax rate on working holiday makers, become more problematic when viewed in conjunction with other impacts affecting agriculture. Thus, the ‘backpacker tax’ risks making food security harder to maintain at a time when Australia's agricultural system is already vulnerable to climate change.  相似文献   
6.
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   
7.
Historical towers, in particular medieval towers, are an important part of cultural heritage, and their preservation mandates monitoring and detailed analyses of vulnerability under seismic actions as well as of their long-term performance. Certain aspects of structural nature are linked to the masonry behavior as a unilateral material, and other are aspects related to the interaction with soft soil conditions. This study aims to contribute to the aspects of preservation by exploring the role of the soil-structure interaction in predicting the behavior of the structures, with specific reference to the well-documented case history of the medieval Ghirlandina Tower (Modena, Italy). A significant contribution comes from an experimental identification analysis, performed in the presence of ambient vibration. A novel finding is that the soil structure interaction cannot be neglected, in contrast to most published identification analyses that usually assume the structure to have rigid constraint at base.  相似文献   
8.
一场甲午战争,使东亚海权格局剧变,由此构成中日两国命运变化的历史拐点。战前,中日两国面对西方殖民扩张的相同遭遇,展开了近30年的海军现代化建设,并在互为敌手的竞争中日益凸显于以英国为主导的东亚海权格局之中。然而,不同的战略选择决定了不同的命运,甲午战争用血与火诠释了海权与海防的本质区别及其决定性影响。正因为战败后的中国已完全置身于东亚海权格局之外,再次陷入有海无防的境地,导致海权得以坐大的日本推行"大陆政策"更加有恃无恐,在列强瓜分中国的狂潮中走上独霸东亚之路。  相似文献   
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10.
It is not until the fourteenth century that written records offer a glimpse into the coastal societies of Northern Sweden. Records include references to a social stratum referred to as the birkarlar, who were tradesmen engaged in trading with the Sámi. The origin of the birkarlar, their prominent status and the meaning of the term, is an enigma that has been much disputed among scholars although there is consensus about the economic and fiscal supremacy of birkarlar vis-á-vis the Sámi. However, the paradox of tradesmen employing force against their most important circle of suppliers and customers remains a puzzle. The birkarla institution is analyzed by means of alternative reading of historical records from the perspective of the indigenous Sámi and coastal farming communities. The postulated animosity between Sámi and the birkarlar is critically examined in light of the social and economic context of interior and coastal communities during the Late Iron Age and Early Medieval period, and in relation to historically known Sámi kinship relationships and marriage traditions. Data are analyzed with regard to demography and social structure, and from a landscape perspective including the logistics and practicalities of inter-cultural contact. Analyses corroborate that birkarlar were deeply rooted in the coastal communities and fully involved in the regular subsistence activities. They were representatives given a commission of trust and contacts between the birkarlar and the Sámi were characterized by mutuality and inter-dependence.  相似文献   
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