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91.
92.
Abstract

This article aims to highlight the mechanisms through which institutional arrangements influence the morphology of residential development. By comparing the Netherlands, Flanders and North Rhine-Westphalia, which have quite similar socio-economic and landscape characteristics, it investigates how differences in national institutional environments have contributed to differences in the urban morphology of residential areas. This article fits within a broader institutional “turn” in planning research. While most of these studies focus on how institutions affect the behaviour of actors in the process of planning and development, this article focuses on the physical outcomes of these processes. The institutional analysis of physical outcomes suggests that urban morphology is not only linked to planning systems—the subject of this special issue—but also to housing cultures and property regimes.  相似文献   
93.
Ancient mortars played a crucial role in the construction of historical architectures due to their physical and chemical compatibility with traditional building materials such as stones and bricks. Therefore, the analysis and optimization of the ancient mortar formula are significant in the restoration and preservation of historical sites. In this work, 20 mortar samples selected from five ancient stone pagodas in Zhejiang Province, China, were analyzed. The results showed that mud, lime-soil mortar, lime-sand mortar, and lime-gypsum mortar were used as binders in these pagodas. The Ca(OH)2/aggregate ratio ranging from 0.3 to 2.7 was usually used to prepare lime mortar. Protein and polysaccharide were also found in some samples.  相似文献   
94.
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   
95.
Smoking bans have recently expanded to private vehicles in which children are present. This study considers the place of children's rights and children's voices in this policy initiative, with respect to the Canadian context, where vehicular smoking bans have been widely adopted. First, we examine print media reports, finding children's right to health was acknowledged less frequently than an array of competing adult rights. Children's voices were largely absent from the record. Second, we report on focus groups involving 23 young people in Edmonton, Alberta, highlighting participants' strong support for bans, based on their knowledge of health harms, aversion to smoke, and awareness that children have limited ability to contest adult authority in vehicles. We conclude that vehicular smoking bans may address the situation whereby children are forced to share an unhealthy environment, in breach of their rights.  相似文献   
96.
This paper presents a review of services sector development in China. It is found that China’s services have recently emerged as the dominant contributor to economic growth and job creation. Trade in services has also increased dramatically, although China maintains a huge deficit. In comparison with economies at a similar stage of development, however, China’s services sector is lagging behind. Both GDP and employment shares of the services sector are relatively small. Services trade also accounts for a relatively small share of China’s total trade. In particular, China’s new services are underdeveloped. As per capita income rises and resultant urbanization accelerates, the country’s services sector is expected to expand further and hence play a key role in rebalancing China’s economy away from its over-reliance on manufacturing and exporting. To reach this goal, further reforms and prudent government policies are needed.  相似文献   
97.
The long established distinction between civic nationalism and ethnonationalism is useful heuristically to understand different dimensions of nationalism and perhaps track a movement from ethnic forms to civic allegiances, though some have challenged its empirical veracity and others question the normative implications of such a distinction. This paper demonstrates the ways in which the two are elided in everyday discourses about migrants in Australia. We argue suspicion of cultural difference, identified more than three decades ago as the new racism, has given way to talk of the need for migrants to ‘follow the law’. This serves rhetorically to reinforce the notion that migrants, often implied to overlap with the category ‘Muslims’, are insisting on breaking the law and/or changing it and are therefore culturally incompatible with a modern liberal democracy. We argue that since ethnic nationalism, like racism, is out of favour normatively, ethnic nationalist arguments are now superficially concealed beneath the acceptable language of civic nationalism. The manner in which this occurs is mapped discursively using data from a corpus of twenty seven focus groups conducted around Australia.  相似文献   
98.
CO2 injected into rock formations for deep geological storage must not leak to surface, since this would be economically and environmentally unfavourable, and could present a human health hazard. In Italy natural CO2 degassing to the surface via seeps is widespread, providing an insight into the various styles of subsurface ‘plumbing’ as well as surface expression of CO2 fluids. Here we investigate surface controls on the distribution of CO2 seep characteristics (type, flux and temperature) using a large geographical and historical data set. When the locations of documented seeps are compared to a synthetic statistically random data set, we find that the nature of the CO2 seeps is most strongly governed by the flow properties of the outcropping rocks, and local topography. Where low‐permeability rocks outcrop, numerous dry seeps occur and have a range of fluxes. Aqueous fluid flow will be limited in these low‐permeability rocks, and so relative permeability effects may enable preferential CO2 flow. CO2 vents typically occur along faults in rocks that are located above the water table or are low permeability. Diffuse seeps develop where CO2 (laterally supplied by these faults) emerges from the vadose zone and where CO2 degassing from groundwater follows a different flow path due to flow differences for water and CO2 gas. Bubbling water seeps (characterized by water bubbling with CO2) arise where CO2 supply enters the phreatic zone or an aquifer. CO2‐rich springs often emerge where valleys erode into CO2 aquifers, and these are typically high flux seeps. Seep type is known to influence human health risk at CO2 seeps in Italy, as well as the topography surrounding the seep which affects the rate of gas dispersion by wind. Identifying the physical controls on potential seep locations and seep type above engineered CO2 storage operations is therefore crucial to targeted site monitoring strategy and risk assessment. The surface geology and topography above a CO2 store must therefore be characterized in order to design the most effective monitoring strategy.  相似文献   
99.
In the fourth millennium BP, there were major environmental and cultural changes on the Andean altiplano of South America, but the chronology remains vague. A recent synthesis describes a slow, gradual transition from hunting and gathering to agropastoralism. This proposal is tested by refining the date of the onset of more humid and stable conditions, around 3550 cal BP, based on a Bayesian model of 26 dates from Lake Wiñaymarka and an updated calculation of the lacustrine offset. This is compared to Bayesian models of 191 dates from 20 archaeological sites, which incorporate a number of recently processed radiocarbon dates. A synthesis is presented of 15 full coverage surveys, a summed probability distribution, and a Bayesian model of the transition to ceramics, which together support a scenario of a very rapid demographic increase. Fourteen models from archaeological sites are cross-referenced in a composite model, which identifies a brief, altiplano-wide emergence of agropastoralism with starting and ending boundaries of 3540 and 3120 cal BP, respectively. This starting boundary correlates strongly with the onset of improving environmental conditions, indicating synchronous cultural and environmental change. The suite of accelerating cultural changes included a marked reduction in mobility, a demographic surge, increased subsistence diversity, the adoption of ceramics, farming and the integration of camelid herding into a remarkably resilient economic strategy still in use today. This is a highly relevant but yet to be used comparative case study for the variable tempos of ‘big histories’, and ecocultural interactions that generate rapid, emergent episodes of wide-spread and enduring cultural change.  相似文献   
100.
宋广波 《安徽史学》2015,(6):163-168
本文考证了胡适致任鸿隽、胡近仁两封信的写作时间,纠正了以往的误判。将信件的内容置于广阔的历史背景下加以考察,并与相关史料参考互证,不仅有助于考察信件的写作时间,且有助于理解信函的真实含义。  相似文献   
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