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61.
Domestic tourism is a neglected theme within tourism scholarship about the global South. This article addresses informal sector domestic tourism and is anchored upon the typology of tourism by Gladstone (2005) in which distinctions are drawn between international and domestic tourism and formal and informal sector tourism. The specific focus is informal sector business tourism, the nature of which challenges Western definitions of business tourism. The study reports findings from 52 interviews conducted with informal business tourists and accommodation providers in Maseru, Lesotho’s capital city. It is revealed the nature of low-income informal sector business tourism in the global South is radically different to that of conventional business tourism in terms of its organisation, characteristics of business tourists, and impacts. Arguably, informal sector business tourism is inherently pro-poor in its local impacts. Further comparative research work is required concerning these forms of ‘invisible’ tourists in African cities. 相似文献
62.
Private Finance Initiative (PFI) has been used on many projects in the UK in the delivery of public services. Cost, time and risk performance in public projects was anticipated to be improved by the superior skills of the private sector. So far, there are limited empirical studies on the life cycle performance of PFI projects, especially performance comparison between different sectors. This study investigated and compared variations in costs, time, and client requirements tracking it through the strategic business case stage to the operational phase in healthcare and transport sectors. It explored the influence of sector-specific factors, project size and maturity of the PFI on these variations. It used documentary analysis of full business cases of five PFI projects and a questionnaire survey of 44 PFI projects in the UK. The findings reveal that there are still considerable cost and time overruns and requirement changes in PFI projects in both sectors over the development of the project and its early use. The health sector was better than the transport sector for time overruns but was worse on costs. Smaller-value projects outperformed larger projects on cost variations but underperformed on time. 相似文献
63.
Amalie Gunner Siamak Rahimi Ardkapan Alireza Afshari Niels Christian Bergsoe 《土木工程与建筑:英文版》2014,(4):389-394
An emerging issue in Denmark is passive smoking in residential buildings where non-smokers are exposed to smoke from their neighbours. There are various ways that smoke is transferred from one flat to another. The air transfer rate between two flats in a multi-storey building depends on its construction, tightness and age. This paper presents results of a study on the transfer of ultrafine particles and tracer gas in an older multi-storey building in Copenhagen. The aim of the study was to quantify the transfer ofultrafine particles and gases from one flat to another fiat before and after sealing the floor. A new floor-sealing method was applied to seal the floor between the two flats. The sealing method was developed by a firm specialising in sealing. Indoor ultrafine particle concentrations and tracer gas were measured continuously in the two fiats during the measuring periods. In the unoccupied fiat, the gas source was N20 and the particle source was burning cigarettes. Reduction of the concentration of ultrafine particles and tracer gas by sealing the floor with polyethylene and joint filler made of bitumen was studied. It was evaluated how the sealing performed with regard to decreasing the amount of ultrafine particles and a tracer gas transferred between two fiats separated by a floor. When the floor between the flats was not sealed, the results showed that about 4% of the ultraflne particles and 14% of the tracer gas were transferred. After sealing, the amount transferred was reduced to 1.6% and 5%, respectively. 相似文献
64.
South Africa’s experience with spatial economic interventions has had a chequered history with the Industrial Development Zone programme most recently failing to generate anticipated development. Current policy has shifted to the imminent launch of Special Economic Zones (SEZs) as tools for national (re)industrial development and supporting underdeveloped regions. This paper reflects on recent South African experience with spatial economic interventions and international experience with SEZs paying particular attention to their strengths, weakness and key establishment considerations. It is argued that unfolding South African SEZ planning can be strengthened by learning from the ‘good’ and ‘bad practice’ of international SEZs. 相似文献
65.
66.
Maren Schubert Christoph Dauberschmidt Christian Eltschig Dirk Nechvatal Markus Rapolder Tobias Schedl 《Beton- und Stahlbetonbau》2016,111(9):564-575
Research of production and maintenance costs for alternative concepts to ensure the durability of parking buildings There is currently an intense discussion about how to ensure the durability of parking buildings. Without having carried out a comprehensive cost analysis for the alternatives for durability concepts costs are nevertheless used as an argument for or against a certain execution. In this publication the costs of various execution concepts are compared on the basis of a virtual two‐storey underground garage with standard dimensions for the two major components of ”suspended ceiling“ and ”baseplate“. For instance the cost analysis includes the production costs for the minimum reinforcement in dependence of the examined surface protection or of the waterproofing system respectively. Furthermore the costs for maintenance, inspection and repair among other aspects are compared in dependence of the surface protecting system for a service life of 50 years. This cost approach takes into account consists of market fluctuations as well as scheduled maintenance cycles by considering medium, minimum and maximum costs. For the suspended ceiling the following coating or waterproofing systems respectively are examined: surface protection system ”OS 11“; ”mastic asphalt (single/double layer) with asphalt sheeting ”; ”mastic asphalt (single/double layer) with surface protection systems OS 10“ and ”PMMA“ protecting surface system. For the base plate two load cases are investigated: ”water exchange zone“ (WW) and ”water pressure“ (WD) in combination with the following surface protection systems: ”OS 11“, ”mastic asphalt (single/double layer) with asphalt sheeting“ and ”OS 8 with accompanying crack treatment“. For the ongoing maintenance costs, engineering values are chosen in accordance to the current state of knowledge. It is expected that current research projects are going to provide scientific results in the near future allowing an update of this cost analysis. 相似文献
67.
Thorsten Helbig Kay Unterer Christian Kulas Sergej Rempel Josef Hegger 《Beton- und Stahlbetonbau》2016,111(10):676-685
Pedestrian bridge made from carbon‐concrete in Albstadt‐Ebingen – First entirely carbon‐reinforced concrete bridge worldwide The bridge erected in Albstadt‐Ebingen in October 2015 is realized without any steel reinforcement or pre‐tensioning, making it the world's first entirely carbon‐reinforced concrete bicycle and pedestrian‐bridge. The trough section with material thicknesses of 70 mm (trough walls) and 90 mm (slab) respectively has been fabricated as monolithic pre‐cast element. With a span length of 15 m and a width of 3 m, the bridge‐deck requires no further coating and has a total weight of just 14 tons (approximately 310 kg/m2); this is about 50 % of comparable conventional reinforced concrete bridge‐decks. Besides material and weight savings, an exceptionally long service life with minimal maintenance can be expected, as the steel corrosion that is typical in reinforced concrete structures can be entirely avoided. Since the use of carbon‐reinforced concrete (carbon concrete) is not yet approved in Germany, the client had to obtain approval based on individual cases (ZiE). 相似文献
68.
69.
Time series of satellite data, generated by the AVHRR (1981-1999), CZCS (1979-1985) and SeaWiFS (1998-2002), have been used to assess trends and interactions of physical and bio-geo-chemical features in the Adriatic Sea. The images were processed to estimate Sea Surface Temperature (SST) and Chlorophyll-like Pigment Concentration (CPC). Long-term composites and climatologies were derived, using fixed geographical grids and projections. The AVHRR data show an apparent warming trend, when plotting the sequence of seasonal cycles (monthly mean SST, averaged over the whole basin) against time, due to a steady rise of summer values. Considering 3 regions (north, central and south), split into east and west sections, the northern Adriatic shows high SST fluctuations (possibly associated with the cycle of winter cooling and summer warming, typical of the relatively shallow sub-basin), while the southern Adriatic exhibits a lower variability (possibly influenced by the periodic water incoming from, and outflowing to the Ionian Sea). During summer, an east-west gradient prevails, while during winter only a general north-south gradient can be found. The SeaWiFS-derived CPC values, distributions and trends appear to be consistent with the historical CZCS record. Persistent differences in the quantitative assessment of CPC for coastal waters is due to the use of improved algorithms, less influenced by the presence of dissolved organics and suspended sediments in the water column, for the processing of SeaWiFS data. Apparent incongruities of the space and time patterns in the SeaWiFS record with respect to the reference climatology, obtained by CZCS more than a decade before, occur chiefly when considering the spring bloom in the southern Adriatic and the summer development of the north Adriatic front. The comparison of the long-term times series of satellite data shows that there is a high correlation between patterns in the thermal field and in the colour field. This suggests that different surface waters, identified by the SST index, are also traced by different ecological features, identified by the CPC index. Both indices also show a high correlation with the classical cyclonic circulation scheme of the Adriatic Sea, proposing once again an intimate relationship between the water dynamics and its bio-geo-chemistry. 相似文献
70.
Christian Richters 《中国建筑装饰装修》2012,(1):42-45
不论内外,这座建筑都透着动感,令你感受到那种亮丽完美,建筑师们所谓的"天堂制造"的效果。这座建筑浑身上下,都吸引着人们的眼球。为了在视觉上和空间上达到一种流动性的通畅空间效果,建筑师引入了一个公共的空虚空间,将光线投射到地板上,同时从视觉上将不同楼层相连接。为了内外空间之间的衔接,建筑外立面的一侧设计了一个只有12层高的纵深空隙空间,而不是一个与建筑一样纵深的空间。该空间成为建筑内部连接整个建筑的部 相似文献