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1.
Environmental stewardship—a concept that describes the relationships between humans and the environment—is gaining increased attention as an approach that can address planetary sustainability issues. In-depth empirical investigations of local environmental stewardship are needed to understand how social-ecological context influences stewardship, as well as the arrangement of conceptual elements in applied settings. This study addresses these needs by conducting an in-depth exploration of environmental stewardship in the Niagara Region of Canada. A single embedded case study design is employed, with environmental stewardship initiatives constituting the individual units of analysis with the case. Analysis of the spatial arrangement of a total of 89 initiatives indicated that initiatives tended to cluster closer to the Niagara River and in more populous municipalities. The significance of collaboration, tensions between the environment and economic development, and concerns about political impacts emerged as themes across contextual factors. The configuration of stewardship elements reveals interesting discrepancies between initiatives and previous stewardship research focused on larger scales, individuals, and organizations. Further analysis is encouraged to illuminate environmental stewardship in other settings as well as advance relational understanding of conceptual elements.  相似文献   
2.
孙小龙  林璧属  郜捷 《人文地理》2018,33(1):143-151
旅游体验是游客情感价值的累积。旅游体验质量评价是对游客心理累积情感的测度,科学、准确的核算游客体验质量是旅游景区、旅游企业等可持续发展及竞争力提升的重要保障。本文通过对1980-2015年发表于国内外旅游及管理领域重要期刊文献的梳理,从服务质量研究的历史、科学视角及与旅游融合的角度对旅游体验质量评价的研究进展、理论基础等进行系统的回顾,并从体验质量评价的理论视角、思路、特征、类型与准确性、可操作性、应用范围等中观层面,对所梳理出的4类国外主流质量评价范式进行旅游体验哲学视角下的解读、比较分析和总评,最后对该领域未来研究重点进行展望。  相似文献   
3.
Accurate simulation of multiphase flow in fractured porous media remains a challenge. An important problem is the representation of the discontinuous or near discontinuous behaviour of saturation in real geological formations. In the classical continuum approach, a refined mesh is required at the interface between fracture and porous media to capture the steep gradients in saturation and saturation‐dependent transport properties. This dramatically increases the computational load when large numbers of fractures are present in the numerical model. A discontinuous finite element method is reported here to model flow in fractured porous media. The governing multiphase porous media flow equations are solved in the adaptive mesh computational fluid dynamics code IC‐FERST on unstructured meshes. The method is based on a mixed control volume – discontinuous finite element formulation. This is combined with the PN+1DG‐PNDG element pair, which has discontinuous (order N+1) representation for velocity and discontinuous (order N) representation for pressure. A number of test cases are used to evaluate the method's ability to model fracture flow. The first is used to verify the performance of the element pair on structured and unstructured meshes of different resolution. Multiphase flow is then modelled in a range of idealised and simple fracture patterns. Solutions with sharp saturation fronts and computational economy in terms of mesh size are illustrated.  相似文献   
4.
The restoration of destroyed connections of epistyles joined together by means of metallic connectors is among the most difficult problems encountered by scientists working for the conservation/restoration of monuments made of marble. The complexity of the geometry and the interaction of three completely different materials (metal-filling material-marble) constituting the connection render the study (either experimental or analytic) extremely complicated. In this direction a numerical analysis is presented here in order to deeply understand the response of a typical ancient connection subjected to axial loads as well as to quantify the influence of some geometric parameters on its response. The parameters studied include the length of the connector, the width of its flanges, the depth of the groove (mortise), the existence or not of relieving space and the filling material’s volume. The numerical model was calibrated and validated according to the results of an earlier experimental study realized on the worksite of the Parthenon Temple. It was concluded that the interventions required to relieve the stress field by changing the size of the connector are disproportional to the respective positive effect on the response of the connection. Moreover it was proved that the most beneficial parameter is the relieving space.  相似文献   
5.
This article aims at presenting and discussing the strategies for updating the finite element numerical modeling of stone masonry arch bridges using operational modal analysis. The study comprehended three bridges: two old ones, the St. Lázaro and the Lagoncinha bridges, and a recently constructed bridge in Vila Fria, Portugal. Updating of the bridge models is performed by comparing the numerical and experimental modal parameters. Three-dimensional detailed numerical models are used to perform modal analysis of the bridges. Experimental modal identification of the bridges is based on the measurement of their acceleration responses during normal operation. The assigned material properties are also based on available results obtained from in situ and laboratory tests and on the results of visual inspection and historical research carried out for both old bridges.  相似文献   
6.
大营子冶炼遗址位于赤峰市翁牛特旗五分地镇大营子村南侧的大山的北坡上,包含东西两区冶炼遗存。东区冶炼遗存年代较早,至迟在公元前1 400年已开始冶炼活动。铅同位素、微量元素示踪研究显示大营子冶炼遗址东西两区均使用了来自林西县大井古铜矿的多金属共生矿石,直接冶炼铜砷锡三元青铜合金。大营子冶炼遗址东区冶炼遗存的年代测定,获得了迄今为止最早的夏家店上层文化年代测定结果,为探讨辽西地区青铜时代考古学文化的演变提供了新的科学证据。  相似文献   
7.
The mensuration of multi‐elemental concentrations from assorted archaeological materials has always required great care and attention to detail to ensure good‐quality data and their ensuing interpretations. Although most suspect data were generated before the wide use of computers, error‐free data are not still a certainty. This paper presents the geochemical rationale for a proposed chemical data‐assessment process, using a globally dispersed collection of ceramic, sediment and lithic data. It is argued that this process can allow archaeologists and archaeometrists to investigate systematically older and current data sets and, if need be, alter them to the reliable values they were originally intended to include.  相似文献   
8.
朱定秀 《安徽史学》2007,4(3):13-16
国家恐怖主义是由政府实施的恐怖主义,法西斯主义则是国家恐怖主义发展到登峰造极的产物.国家恐怖主义具有制度化、公开性和社会化的特点,并具有独裁政治,庞大的镇压机器,镇压性的特务机关,非人道的人身迫害,非战争状态下对大量人口的集体收监、屠杀或迫使其流亡,针对社会知名人士的暴力行为等构成要素.  相似文献   
9.
The generation of computational meshes of complex geological objects is a challenge: their shape needs to be retained, resolution has to adapt to local detail, and variations of material properties in the objects have to be represented. Also mesh refinement and adaptation must be sufficient to resolve variations in the computed variable(s). Here, we present an unstructured hybrid finite element, node‐centred finite‐volume discretization suitable for solving fluid flow, reactive transport, and mechanical partial differential equations on a complex geometry with inhomogeneous material domains. We show that resulting meshes accurately capture free‐form material interfaces as defined by non‐uniform rational B‐spline curves and surfaces. The mesh discretization error is analysed for the elliptic pressure equation and an error metric is introduced to guide mesh refinement. Finite elements and finite volumes are represented in parametric space and integrations are conducted numerically. Subsequently, integral properties are mapped to physical space using Jacobian transformations. This method even retains its validity when the mesh is deformed. The resulting generic formulation is demonstrated for a transport calculation performed on a complex discrete fracture model.  相似文献   
10.
The remains of the fragmented skeleton of a mature male individual from a Neolithic mass burial (ca. 5000 years BP) are presented. The lesions consist of osteoblastic proliferation and replacement of previously normal haematopoietic tissue. The most affected area seems to have been the iliac blade. So-called ‘seeding’ of tumour tissue has been found in different loci in the femoral neck, sacrum, L4 and scapula. Differential diagnosis points to metastatic carcinoma, most likely from the prostrate gland. In order to support the observations, radiological and histological analyses have been performed. Trace element analyses of tumour and control samples have shown the limited contribution of these data to ascertain the aetiology of secondary neoplasias in buried material.  相似文献   
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