Study of convective phenomena inside cavities coupled with heat and mass transfers through porous media—application to vertical hollow bricks—a first approach

Building structures often contain cavities or strips of air. Because of this, it is difficult to describe the transfer phenomena that are in fact heat transfers (conductive, convective and radiative), as well as mass transfers through porous media. Numerous studies have dealt with each of these transfers separately but few have managed to describe the interrelation between them. This paper represents an initial approach to the problem, by attempting to describe the influence of the moisture level on heat transfers occuring through hollow vertical terra-cotta bricks. A theoretical modeling of exchanges has been carried out in order to determine radiative and convective exchanges coefficients. A mass exchange coefficient has then been deduced. The results obtained show a high sensitivity of the heat flux to the moisture level of the surroundings.     

Numerical simulation of the ‘pull-in’ operation in submarine pipelines

‘Pull-in’ operations consist in the deflection of a pipeline, resting on the seabed, until it is ready to be connected to a subsea oil production structure. This work presents the numerical methods and strategies employed in the development of a computational system for the simulation and analysis of such operations, involving severe geometric nonlinear effects due to large displacements. The following aspects are addressed: representation of the pipeline; anisotropic friction in the soil-pipeline interaction; three-dimensional behaviour, and representation of the chain-buoy assembly in ‘off-bottom’ operations; and the adequate representation of the pull-in cable. The study of the final connection to the subsea structure is also addressed. The quality of the numerical simulation obtained from the application of this computational system is assessed in an illustrative example, where the results are compared with those obtained from an experimental small-scale model test.     

Evaluation of natural illumination and thermal comfort conditions in the Ribeirao Preto’s Technological Village

The results of post-occupancy surveys of the 11 different construction systems used in the dwellings of the Technological Village of Ribeirao Preto are analyzed. The analyses focus on evaluating the natural illumination and thermal comfort conditions in selected habitation units after 2 years of use. All systems were devised to provide living conditions to low-income families with low purchasing power and, most importantly, to disseminate construction technologies adapted to, and appropriate for, this specific region of the country. The results indicate that the methodology employed is not appropriate using only classical factors to assess the illumination conditions, i.e. illuminance level and daylight factor, for a direct quantification of the illumination. The isolated use of these factors can result in distortions. The evaluation of the environmental conditions is relevant to observe that there can be differences between theoretical thermo-physical properties and actual features of the materials and construction systems analyzed.     

A combined experimental and simulation method for appraising the energy performance of green roofs in Ningbo’s Chinese climate

A passive means of lowering the energy demand of buildings is the application of green roofs. The complexity between heat and moisture exchanges in green roof layers and the large variations of green roof types make the need for experimental or simulation assessments necessary for quantifying the energy benefits from green roofs. The current treatment of green roofs in simulation programs is either over-simplistic, for example by ignoring heat and moisture exchanges such as evapotranspiration, or the more advanced models have limitations and require inputs that are rarely available in practice. In this paper a combination of experimental and modelling techniques are used to assess the potential heating and cooling load reductions from the application of green roofs in the subtropical climate of Ningbo in China. The method provides a generalised energy performance assessment of green roofs in Ningbo by overcoming the limitations of existing green roof simulation models.     

Numerical simulations of the failure process of anaclinal slope physical model and control mechanism of negative Poisson’s ratio cable

Bulletin of Engineering Geology and the Environment - Occurrence of toppling failure has been prominent due to the increasing of infrastructure construction, such as road slopes, dams, and...     

Shaping Seoul’s memories: the co-evolution of memorials,national identity,democracy and urban space in South Korea’s capital city

This paper examines the evolving subjects, forms, symbolism, and spatial constellation of the diverse memorials erected in Seoul since 1953. It explores how these memorials have expressed shifts in national identity towards democracy since the end of dictatorship in 1987. It illustrates how commemorative intentions in this massive, rapidly-changing metropolis have intersected with other urban design aims and pressures. The analysis reveals an evolutionary progression in memorial themes, from heroic statues that re-establish roots of Korean national identity and independence, to marginal grassroots memorials and wider themed precincts that present more inclusive, democratic, complex narratives of identity and history.     

Growth and degradation in the Orient’s ‘Las Vegas’: issues of environment in Macau

This paper argues that the rapid growth of gambling‐related tourism and urban construction in Macau has given rise to serious environmental degradation. The major environmental issues include air quality, water supply, solid waste disposal, noise prevention, heritage conservation and environmental management. The author suggests that the government in Macau should refocus this city’s development direction and commit itself to sustainable development. At the policy‐making level, there are such urgent issues as integration of environmental, economic and urban planning with community participation in decision‐making; enhancement of environmental legislation and institutions; implementing vital measures to control of the numbers of visitors; developing a mass transport system; and protecting the city’s cultural heritage.     

Contribution and challenges of the private sector’s participation in housing in Nigeria: case study of Akure,Ondo state

Housing inadequacy in Nigeria’s rapidly growing urban centres is manifested in qualitative and quantitative terms. Government’s efforts at mass delivery of houses have failed to achieve the desired result, hence the collaboration between the public and private sector to bridge the wide housing gap. A study into the public–private partnered initiatives at mass delivery of housing in Akure, Nigeria was undertaken. Seven housing schemes of this sort were identified and studied, taking their contributions to bridging the housing gap in the city into account. The achievement is meagre though progressive strides are discernable. The macroeconomic environment, continued dominance of the public sector, bureaucratic bottlenecks, and socio-cultural issues presented serious challenges to active private-sector participation. Affordability is elusive; execution of the projects had some problems while political manoeuvrings impacted on the projects negatively. It is affirmed that participation of the private sector has potential for improving housing delivery; however, the present operation needs to be fine-tuned for future success.     

Virtual enclosure,ecosystem services,landscape’s character and the ‘rewilding’ of the commons: the ‘Lake District’ case

Abstract

It is paradoxical that, while there is a generally increasing recognition of the scientific and cultural importance of conserving ‘semi-natural’ pastoral environments, and the negative effects of their widespread abandonment and overgrowth, British ‘rewilding’ activists and environmental managers are effectively advocating policies that will have a similar negative effect on the character of the semi-natural pastoral commons of places like England’s iconic Lake District. This situation, it will be argued, owes to the mindset of ‘virtual enclosure’ whereby the character of landscape is pre-defined by an assumed, behind-the-scenes, Euclidean/Ptolemaic spatial logic that leads to the comprehension of nature as a bounded scenic property; an (e)state of nature with its own economic system and services. This mindset is antithetical to both the practice of pastoral commoning and much contemporary natural science and conservation policy. It fits well, however, with older teleological ideas of nature, as well as modern ideas of privatisation, private property and management control.     

Courtyard in conflict: the transformation of Beijing’s Siheyuan during revolution and gentrification

After Liang Sicheng’s effort to preserve ‘Old Beijing’ failed, vast areas of traditional hutong neighbourhoods were cleared to make way for socialist monuments and work-units. From the 1950s onwards collectivisation that forced siheyuan dwellers to share their homes with ‘comrade tenants’, especially after the Cultural Revolution when courtyard owners were persecuted, remaining siheyuan houses had been dirty and crowded, known as dazayuan, mostly occupied by working-class families, until recently, when the ‘socialist market economy’ rendered such neglected residences profitable. Wealthy property developers evicted the local population, often not without forced relocation and government cooperation, and refurbished these courtyard houses as ‘new siheyuan’ for sale to the emerging business elites and celebrities.

This article explores the transformations of Beijing’s siheyuan against the turbulent history of China since the mid-twentieth century. It illustrates the ways in which architecture was reconfigured to channel and contribute to the broader social and ideological missions of the CCP. Whilst the construction of monuments propagated a positive image of the regime through grand ceremonial events, the tragic experiences of the courtyards’ inhabitants during both revolution and gentrification embodied the penetrating depth and far-reaching consequence of the Party’s social and ideological engagement in the daily life of the common people. The former operates on the symbolic level with landmarks, satisfying growing nationalism with the promise of a powerful country of which to be proud, and the latter on the practical level with day-to-day dwellings, first accommodating the urban proletarians as a product of the revolution then satisfying the emerging commercial elites in a society of growing capitalism. The control of domestic space became an important part of Chinese governance, for which the reshaping of people’s lives through architecture served as a crucial measure to legitimate the regime in ideology and to provide support for its changing political agenda.     

Satisfaction Levels and the Community’s Attitudes Towards Urban Renewal in Alexandra, Johannesburg

In South Africa, the spatial legacy of Apartheid has resulted in township areas that can be recognised as intense concentrations of poverty. Variations in the types of housing, often dominated by informal structures and overcrowded conditions, are characteristic of these areas. As such, they are generally perceived as areas of limited economic potential. In response to these conditions and in an attempt to alleviate the associated problems, the African National Congress government has initiated an Urban Renewal Programme in eight nodes in six urban areas in the country. Alexandra in Johannesburg is one of these nodes. The programme and service delivery in this township is a controversial issue that reached boiling point during instances of civil unrest in 2011. The renewal programme entails the demolition of housing units, the relocation of the inhabitants, as well as the expropriation of properties for redevelopment by the developers. This perception study on the success rate of the renewal programme was conducted in four sectors of Alexandra, namely East Bank, River Park, Tsutsumani and Tswe??tla, each with its own housing and socio-economic characteristics. This paper evaluates the effectiveness of the Urban Renewal Programme as perceived by the inhabitants in the delivery of public services such as sanitation, water supply and electricity, and the provision of housing, health facilities, educational and recreational facilities. On the visual front, the programme appears to be meeting with success, particularly in terms of the provision of housing. The beneficiaries, however, are generally of the opinion that management and/or the government is not making enough of an effort to meet their expectations.     

The effects of Seoul’s greenbelt on the spatial distribution of population and employment, and on the real estate market

This paper examines the effects of Seoul’s greenbelt on the distribution of population and employment, and on the real estate market, under the assumption of the complete relaxation of the greenbelt using the random utility-based metropolitan input–output model with an endogenous land market for the Seoul metropolitan area. Simulation results show two important consequences of the greenbelt release. First, the greenbelt release would attract more residents and jobs into greenbelt zones and reduce the population and number of firms in both the central city and outer sides of the greenbelt, thereby implying the reduction of inner city densification and of development beyond the greenbelt. Second, both residential and nonresidential space rents would have declined for the whole metropolitan area from 0.4 to 13.7% had the greenbelt been completely released in 2006, thereby indicating that Seoul’s greenbelt made a contribution to raising space rents by limiting land supply.     

Fully Stressed Piles and Beams in a Winkler’s Medium,End-loaded by an Orthogonal Force,and with Optimum Length

A simplified method of designing fully stressed piles and beams with optimum length in a Winkler’s medium,end-loaded by an orthogonal force and without any point constraint,is proposed. A numerical algorithm distributing the mass by means of the Fully Stressed Design ( FSD) method and updating the moment by finite elements has been first implemented. The use of the FSD method is in general quite simple,and allows to obtain optimum,or close to the optimum,solutions. After having distributed the mass through ...     

What’s in a (Migrant) House? Changing Domestic Spaces,the Negotiation of Belonging and Home-making in Ecuadorian Migration

Migrants’ constructions of their domestic spaces, and their struggle to feel at home in both receiving and sending societies, are an emerging focus of research in migration studies. Housing issues are also a privileged observatory on their transnational social engagement, as well as on the changing boundaries of their membership and belonging. This article addresses the everyday bases of their home-making and house-building practices, drawing on a multi-sited ethnography of Ecuadorian migration to Italy. What can be inferred from the ways in which migrants inhabit their houses “here”, while typically investing in better housing arrangements “there”, as to their alignment towards either society? What do their housing-related practises suggest about the potential to feel locally and transnationally at home, given the structural constraints they are subject to? By tracing the meanings, enactments and locations of migrants’ home, I aim to advance the debate on home and migration in two respects: the persistent materiality which underlies the home experience, and the significance of migrants’ houses, particularly in sending societies, as a window on the mixed social consequences of migration.