Elastic stability analysis of loosely fitted thin liners – A proposed simplified procedure and evaluation of existing solutions

The paper reports the results of an extensive numerical simulation to estimate the elastic buckling pressure and the corresponding thrust and bending moment induced in loosely fitted thin liners. The study is conducted numerically using a two-dimensional (2D) non-linear finite element model that accounts for the effects of large deformations on the stability of loosely fitted liners. The finite element results together with a non-linear multi-variant regression analysis are used to develop simplified non-dimensional formulae that provide the critical pressure, thrust and bending moments, at buckling, based on the liner’s geometry and material properties.In addition, several other analytical and numerical solutions for the same problem are revisited and critically reviewed. For comparison purposes, two of such methods are extended to allow for the calculation of the thrust and bending moment developed at the most heavily stressed point in the loosely fitted liners at the onset of buckling. In general, the comparison reveals the appropriateness of the proposed regression models in predicting the critical pressure and the associated thrust and bending moment induced in imperfect loosely fitted liners. Developed formulae provide designers with a simple and reliable means for ensuring stability and safety of such special type of structures.     

The impact of Germany's Energiewende on the transport sector – Unsolved problems and conflicts

Politically-driven climate protection targets call for decarbonization and a massive reduction of total energy consumption by 2050. A comprehensive transformation of existing transport systems and individual mobility is needed to achieve this. There will be no energy transition (“Energiewende”) without a transport transition. Electromobility provides great savings compared to fossil-fueled transport. In addition information and communication technologies (ICT) have become a key factor of innovation and inter- and multimodality. With all structural changes (e.g. industrial restructuring or social change), converting existing organizational forms and mobility evokes conflicts. For example, competing spatial requirements of the energy sector and mobility as well as the exclusion of certain categories of persons are to be expected. Indeed, the transformation process is slowed down by shortcomings in the combination of energy and transport technologies, organizational culture and regulations. A number of questions still remain unanswered.     

Assessing the impact of international development policies on the process of civil society participation in urban development in the countries of the South: the case of Syria, 2005–2010

This paper seeks to explore the effect of the international development policies promoted by the United Nations Development Programme on civil society participation in urban development process in the countries of the South. More specifically, the case of Syria during the period 2005–2010 was examined. An institutional analysis was conducted in order to investigate the question of whether development institutions in particular contexts, in terms of both the mental models and the organizational forms of development, permitted the space needed to apply this principle in practice. In this, the paper argues the need to promote a proactive approach to enable civil society participation in the countries of the South rather than a normative internationally accepted approach developed in isolation from the given political and institutional context.     

How should urban water be priced? – An empirical analysis for the city of Mekelle,Ethiopia

Urban water utilities have focused on setting water prices to cover average costs, usually using increasing block rate designs. In an attempt to contribute to the use of efficient, equitable, and revenue-sufficient pricing, this paper estimates the long-run marginal and average social costs of water supply in Mekelle city using a multi-product translog cost function that incorporates the shadow price of natural water. Findings show that the marginal social costs of providing one m³ of residential and non-residential water are Birr 5.33 and 7.71 (Birr = Ethiopian currency: 1 Euro ≈ 23 Birr), respectively, while the average current prices are Birr 4.46 and 6.10/m³. On the other hand, the average social costs of residential and non-residential water are estimated at Birr 14.34 and 16.36/m³, respectively, implying that marginal social cost-based prices would still lead to a revenue deficit of approximately Birr 9/m³.     

The impact of immigration on interregional migrations: an input–output analysis with an application for Spain

Developed countries in general, Spain in particular, have experienced a dramatic rise in the reception of foreign workers in the last decade. Among all the economic and social effects originated by the arrivals of immigrants, the literature has paid some attention to the potential effect that this immigration can produce on the internal migration patterns (the so-called “displacement effect”). This paper proposes the use of a multi-region input–output model of migrations for measuring how the reception of immigrants in one region displaces population among all the regions included in the model. From some basic assumptions, the input–output methodology proposed describes how the arrival of one immigrant in one region i, by the dissemination of internal population from i, generates indirect effects on other region j. To illustrate the methodology proposed in the paper, an empirical application for Spain is also included.     

Dematerialising Money? Observations on the Flow of Wealth from Housing to Other Things

This paper examines the extent and relevance of mortgage equity withdrawal (MEW) in the UK. MEW has, of late, been of most interest as a mechanism transmitting the wealth effects of housing into whole economies. Its implications for housing and social policy are less well documented. To redress the balance, the paper first offers a critique of data resources, before drawing from five substantial surveys to document the growing significance and changing style of MEW among British home buyers. The analysis focuses particularly on the under-explored question of what secured loans are spent on, identifying a trend away from reinvestment into housing, towards the consumption of other things. The study concludes by arguing that ‘wealth effects’ might usefully be recast as ‘equity leakage’ if the aim is to safeguard the quality of the stock and appreciate the limits to housing wealth as an asset base for welfare.     

Is the price of water for residential use related to provider ownership? Empirical evidence from Spain

This paper assesses the relationship between provider ownership and the price of water for residential use set by 386 Southern Spanish municipalities. Our main contribution to the previous literature is that we go much further than merely distinguishing between private and public ownership. First, we find that prices are lower when the urban water service is directly provided by town councils. Second, when water services are contracted out to external companies, the prices set by public utilities are higher than the prices of private utilities due to larger fixed quotas. Finally, water prices are also higher when the provision of the service has been privatised to an institutionalised public-private partnership compared to contractual public-private partnerships.     

Effect of chemical additives on the consolidation behaviours of mini-PVD unit cells –from macro to micro

The mechanism of adding NaCl, CaCl₂ and small amounts of cement/lime (1–4% by dry weight) into clay slurry for mitigating the effect of apparent clogging around PVDs during vacuum consolidation was investigated by mini-PVD unit cell consolidation tests as well as microstructure observations via scanning electron microscopy (SEM) imaging. The consolidation test results indicated that for the specimens with CaCl₂, cement and lime additives the rate of consolidation increased considerably, while the effect of the NaCl additive was limited. The SEM images show that for the specimen without additive, there were obvious localized deformation-induced microstructure anisotropies. For specimens with CaCl₂ and cement/lime additives, the microstructures of the soils tended to be isotropic. The additives tested reduced the thickness of the diffusive double layer around the clay particles and promoted the formation of a more stable flocculated microstructure, therefore mitigating the effect of apparent clogging.     

Use of green roofs to solve storm water issues at the basin scale – Study in the Hauts-de-Seine County (France)

At the building scale, green roof has demonstrated a positive impact on urban runoff (decrease in the peak discharge and runoff volume). This work aims to study if similar impacts can be observed at a basin scale. It is particularly focused on the possibility to solve some operational issues caused by storm water.

For this purpose, a methodology has been proposed. It combines: a method to estimate the maximum roof area that can be covered by green roof, called green roofing potential, and an urban rainfall-runoff model able to simulate the hydrological behaviour of green roof.

This methodology was applied to two urban catchments, one affected by flooding and the other one by combined sewage overflow. The results show that green roof can reduce the frequency and the magnitude of such problems depending on the covered roof surface. Combined with other infrastructures, they represent an interesting solution for urban water management.     

The effect of weak interlayer on the failure pattern of rock mass around tunnel – Scaled model tests and numerical analysis

Weak interlayer is one of unfavorable geological discontinuities often encountered in underground engineering. Many failures of underground openings were reported to be closely related to the existence of weak interlayer nearby. For the purpose of exploring the effect of weak interlayer on failure pattern of rock mass around tunnel, both physical model tests and numerical analysis were carried out to simulate tunnel excavation near an interlayer. In the model tests, by comparison of the failure patterns between homogenous ground and ground with a weak interlayer, it was found that the weak interlayer affected the stability of tunnel by increasing the failure zones and causing asymmetrical stress distribution. The results of model tests were then verified by numerical analysis. Furthermore, based on the numerical analysis results, the location, dip and thickness of the interlayer as well as the distance from the interlayer to the tunnel were proved to be important factors influencing tunnel stability, and the relationships of the induced damage zones with these parameters of the weak interlayer were established. These results can provide a useful guidance for support design and safe excavation of tunnel near or crossing through a weak interlayer.     

The importance of specification uncertainty and intolerance to measurement error in a study of the impact of dentine lead on childrens’ IQs

Needleman et al. concluded that, on average, an increase in the dentine lead of children from <6 ppm to >24 ppm was associated with a 4‐point IQ decrement. Recently, a spate of papers has conjectured that the reports of Needleman et al. and others could be spurious because of measurement error and omitted variable bias. In this Bayesian analysis of the reconstituted Needleman et al. data set, we replace such conjectures by empirical tests. Even though we structure the tests to provide very favourable opportunities for the conjectures to acquire support, the possibility is seen to be remote that omitted variable bias significantly alters the estimated influence of lead exposures upon childrens’ psychometric intelligence. Similarly, the Bayesian analysis demonstrates that other included covariates are likely to affect the estimated influence of lead exposures only if they are quite poorly measured.     

Does the triad of fungi,bacteria and exposure to moisture have an impact on chronic hyperplastic sinusitis?

Here we evaluated a possible relationship between chronic hyperplastic sinusitis (CHS) and moisture exposure and secondly a seasonal variation of fungal and bacterial findings in the healthy nose. In 28 CHS patients sinus mucus was collected during endoscopic sinus surgery. Samples from the nasal cavities of 19 healthy volunteers were collected by nasal lavage (NAL) in January and in September. Bacterial culture and fungal staining and culture were carried out. Histological samples from the sinus mucosa were obtained. Patients' medical history and environmental factors were enquired. Mold odor or moisture problems in the home or work environment were reported by 46% of the CHS patients. Patients who reported moisture exposure did not differ significantly from those who had not been exposed with regards to microbiological findings, tissue eosinophilia, and earlier operations. Cladosporium (16%) and Alternaria (11%) were found in NAL fluid collected in the autumn from the control subjects. No fungi were isolated from samples taken during the winter. An association between CHS or fungal sinusitis and moisture damage was not apparent in the present study. The fungal findings in the nasal cavity reflect the environmental exposure. This should be taken into account when NAL is used for microbiological studies. PRACTICAL IMPLICATIONS: Living in a moldy house or working in a similar environment may increase the risk of respiratory symptoms and infections. However, our results suggest that chronic hyperplastic sinusitis and fungal sinusitis are not associated with moisture exposure. The nose is a good collector of particles in the air. Especially samples taken by the nasal lavage method reflect the environmental exposure. This should be taken into account when this method is used for microbiological studies.     

Mirror of the state or independent image? – Conceptual perspectives on the question of a legitimacy shift to the output dimension in local democracy

This contribution discusses the theoretical and conceptual implications of asking about the legitimacy of local democracy and the relevance of discussing ‘performance legitimacy’. The role of local government in generating or undermining democratic legitimacy is ambivalent. It is questionable whether there can be something like a genuine legitimacy of local government at all, considering its subordinate and functionalised role in the modern (welfare) state. In the first part of the article, the complexity and controversial status of political legitimacy in general and local government in particular is exposed. It is argued that the effective interplay of justification (giving acceptable reasons for policies) and demonstration (performing successfully by fulfilling promises), which is at the core of generating legitimacy, cannot be deduced from general concepts and fixed in a general model. Generating a self-reinforcing dynamic of public support and linking different dimensions of legitimacy (input, throughput, output) is a matter of reflexive institutionalisation. Being part of a democratic welfare state has provided local governments in Western democracies with a stabilised focus of legitimacy. At the same time, local governments are particularly under pressure to adapt, to innovate and to modernise. Four broader narratives of changing democratic legitimacy sources with respect to local government are discussed. The shift to ‘performance legitimacy’ has to be seen in a wider context of redefining the meaning of (local) democracy as mapped out by the four narratives.     

Development and verification of a soil–water coupled finite deformation analysis based on u–w–p formulation with fluid convective nonlinearity

Most soil–water coupled analyses of saturated soil are based on the u–p formulation, where a set of equations is reduced by assuming that the acceleration of the fluid phase relative to that of the solid phase is less than that of the solid phase. Therefore, this analysis cannot be used for a coupled analysis with dynamic water flow in highly permeable soil. This study aims to present a soil–water coupled finite deformation analysis method based on full formulation, or u–w–p formulation. This method differs from conventional methods in the following ways: (1) the governing equations explicitly include the equation of motion for the fluid phase, (2) a relative convective term is used to describe a change in the relative configuration between the two phases, and (3) the moving/inclined discharge boundary is directly implemented to the discretized governing equations. Herein, one/two dimensional seepage and plane-strain deformation analysis results are reported. In the seepage analysis, accelerating permeation of pore water is obtained and the undrained constraint condition is verified. In the deformation analysis, dynamic migration in a high permeable soil specimen, i.e., wave propagation and rotational flow of pore water, is observed.     

Application of statistical power analysis – How to determine the right sample size in human health,comfort and productivity research

The minimum size of subjects required for the research on human health, thermal comfort and productivity is a frequently asked question. In this paper the idea of power analysis, which helps to determine required sample size as well as to interpret research results, is introduced in order to promote good practice of power analysis in the context of human and building environment relationship research. How to calculate effect size from published article or experimental data is presented with plenty of examples. The effect sizes of several physiological and psychological measurements indicating the effect of indoor environment quality on human health, thermal comfort and productivity are presented, which could be worked as references when researchers planning their own studies. How to determine required sample size when planning a study and how to interpret the research results with power analysis are also illustrated step by step with samples. Finally how to make decisions when evaluating the study results is summarized. It is expected that these examples and the summary could help researchers to better apply power analysis in indoor environment quality (IEQ) studies. Some statistical terms used in this paper, such as power analysis, effect size, and t-test, etc., are explained in detail in the Appendix.     

The impact of abandoned/disused marble quarries on avifauna in the anticline of Estremoz,Portugal: does quarrying add to landscape biodiversity?

Although the extractive operations of quarrying are often considered environmental threats, there is some evidence that abandoned quarries may have a significant positive impact on biodiversity by enhancing habitat quality for several species. In Estremoz Anticlinal, SE Portugal, many of the existing marble quarries have been inactive for decades and were abandoned without any restoration project in progress. The impact of quarry abandonment on avifauna diversity was assessed relative to reference conditions using adjacent rural fields as control areas. No significant differences were found in within-community diversity (alpha diversity) between abandoned quarries and reference sites. However, several dissimilarity indices showed a clear divergence in species composition between abandoned quarries and reference sites. Furthermore, statistically significant differences in species compositions were found between quarries abandoned for different periods. Over time, species composition becomes more similar to that observed in reference sites, reflecting ecological succession and landscape resilience to quarrying. Nevertheless, the studied quarrying landscape exhibited higher gamma and beta diversity than the former traditional landscape; thus, our results suggest that abandoned quarries, rather than damaging and destroying niches, can promote new ecological niches and significantly diversify rural landscapes.     

Rethinking tourism narratives on the cultural landscapes of Asturias (Northern Spain) from the perspective of Landscape Archaeology: do archaeologists have anything to say?

As in other rural areas in Spain, the Asturian countryside suffers from a profound demographic and economic crisis. Since tourism emerged as one of the main hopes for the reactivation of rural economy, the regional government has made a particular effort in promoting rural tourism. This paper intends to assess the effects that naturalistic and atemporal narratives of Asturian landscapes exert on the rural farming communities, which define the ‘tourism imaginaries’ as they become established as identity referents not only for visitors, but for the inhabitants of the region themselves. Archaeology can enhance the local communities’ agency through the appreciation of cultural values attached to these landscapes. To this end, the diachronic depth of the social and productive processes which shaped the Asturian landscapes is emphasised by relying on Landscape Archaeology. The relevant role played by farmers and herders in these activities merits their involvement in actively designing future policies.     

Scenario analysis of rainwater harvesting and use on a large scale – assessment of runoff,storage and economic performance for the case study Amsterdam Airport Schiphol

Research on rainwater harvesting mainly focuses on a building scale. Scant information is available about its performance on a large scale. This study aims to determine the potential for, and economic viability of meeting non-potable water demand by rainwater harvesting for a large scale case (21.5 km²): Amsterdam Airport Schiphol. A dynamic model was developed to analyse scenarios of varying rainfall, catchment surfaces and storage capacity. Four potential system configurations of catchments and non-potable uses were analysed for their economic performance with different water prices and storage options. This study found that, given sufficient storage and catchment size, all non-potable water demand of Schiphol can be supplied, reducing drinking water demand by up to 58%. Diminishing returns for adding storage and catchment to the system make full supply inefficient. Current water charges make most large scale system configurations not viable due to high investment costs for supply networks and storage infrastructure.     

Effects of experimental frost–thaw cycles on sandstones with different weathering degrees: a case from the Bingling Temple Grottoes,China

Numerous ancient sandstone grottoes remain in northwest and central China, and weathering issues have significantly influenced their preservation conditions. The dramatic naturally cyclic changes in water content and temperature in the environment have been considered to be the main drivers of the physical weathering that commonly occurs at these archaeological sites. Therefore, comparing and understanding the behaviors of sandstone with different weathering degrees under variable environmental conditions would be helpful for further study on predicting the type, location and extent of deterioration of sandstone relics in a small region (such as the surrounding rock of grottoes). This study examines Cretaceous sandstones with two weathering degrees from Bingling Temple Grottoes, China. Standard thin section photomicrographs provide petrographic and mineralogical data and show that the sandstones have identical lithologies. Three types of specifically designed frost weathering tests are then conducted on the samples. After every six weathering cycles, the weathering processes are suspended, and the corresponding parameters, such as dry weight loss, dry density, effective porosity, porosity, P wave velocity, surface hardness and drilling resistance, are measured. At the end of the weathering cycles, the sample variations in grain size distributions are compared, and statistical tests are performed to show the statistical significance of the results. The results indicate that similar deterioration patterns occur on the samples with two weathering degrees under the same weathering tests. The increase in effective porosity surpasses that of the porosity only when the weathering effect is large enough. Furthermore, sandstone with a high degree of weathering might be more susceptible to changes in the internal pores due to its greater initial interconnectivity. In an open system, physical weathering (frost–thaw and dry–wet cycles) would cause the superficial grain size distributions of different rocks to become relatively uniform. Finally, when exposed to the same weathering process, the decreases in the overall mechanical strength in the two sandstones do not differ significantly, but the loss of superficial strength may be different.