X-ray images of defect formation in porcelain ceramics during drying

The drying phase during the manufacture of ceramic pieces is often the point of failure owing to the formation of cracks. In this study, non-destructive microfocus X-ray imaging has been employed to study the onset of cracking in porcelain and correlate it with the moisture content. Samples of moist porcelain paste were extruded through dies of 30 and 50 mm diameter. Sections of the extrudate were placed into an X-ray transparent oven and imaged while drying at constant temperature and low humidity. The time to the onset of cracking was found to be a function of temperature. The mode of failure was consistent across the temperature range 40–120 °C.The higher the drying temperature, the shorter the time to failure and the higher the moisture loss at failure. For a particular paste consistency and sample geometry there was found to be a critical moisture content below which cracking began to occur. This moisture threshold was observed to be weakly temperature dependent; it appears to be more sensitive to sample geometry and paste consistency. A safe drying curve has been constructed which provides a boundary for the process parameters which prevent cracking. The implication is that during the drying of a ceramic piece, different sections may have different safe parameter boundaries and the process must be designed to keep all sections within the safe region.     

Axial stress waves in an elastic–perfectly-plastic bar

A bar, made from an elastic–perfectly plastic material, fixed at one end, suddenly has an axial load applied at the other end. After its sudden application, the load is held constant. If the load is less than half the yield load for the bar, and in the absence of damping, the load causes a stress wave to pass up and down the bar, all behaviour being elastic. At any point within the bar length, the stress varies, in a stepwise fashion, between zero, and twice the stress corresponding to the applied load. This is the classical elastic solution. However, if the load is greater than half the yield load, when the stress wave first hits the fixed end, yielding will occur, and a simple model is proposed in this paper to allow for yielding. The model incorporates two zones separated by the stress wave, as in the elastic solution, together with a third zone, concentrated, and adjacent to the fixed support, in which all plastic straining takes place. The paper describes and verifies the model, and presents the predictions that it gives for various levels of load.     

Including prospective tenants and homeowners in the urban development process in Finland

The twofold purpose of this paper is to establish the prospective inhabitants as a part of the development process, and to provide an overview of participatory planning in the context of Finnish urban residential public?Cprivate partnerships (PPPs). This overview examines how the future inhabitants of new residential developments can contribute to informed decision-making within a PPP framework. Communicative planning theory serves as a framework to compare the urban development process from the point of view of future inhabitants. Finnish case studies are used to compare the traditional public-led processes with processes based on PPPs. This comparison is discussed within the context of PPPs and how they may evolve further and develop into a public?Cprivate-people partnership (4P) model. The examination of the case studies suggests that involving future inhabitants as stakeholders in the urban planning development process would lead to and require new methods of participation. These methods potentially impact the PPP process as a whole and on several levels. In the Finnish examples discussed here, these range from elements of general planning to individual house design. The research, whilst drawing on the broad field of PPP research, is based on Finnish case studies only. However, this research suggests that the 4P approach is a practical model which may fill the gap between international PPP theory and local, practical solutions for the planning of urban development, both in Finland and elsewhere. Future research can look at this model in other PPP jurisdictions and contexts. The 4P model can be used to establish new methods to plan and develop local infrastructure which meets the needs of future inhabitants. The findings of this paper emphasise the crucial role of future inhabitants in the PPP process. The conclusions points out the possibilities for broad and open participation in urban planning and development processes. The 4P model is found to be a potentially valuable theoretical and practical concept for use in PPP urban developments.     

Adaptation: Altering the House to Restore the Home

A research project into the effectiveness of housing adaptations found some high levels of satisfaction but also examples where considerable expenditure had produced ineffective or even harmful outcomes. An analysis of the ethnographic material suggested that failure to take into account the meaning of home to those receiving adaptations was a cause of wasted expenditure. Alterations to the home that produced an unacceptable image of self that did not restore privacy and a sense of primal security, nor respect the respondent's control within their home, all produced unsatisfactory results. There was also evidence that disregard of home as a base for relationships and for childhood and a lack of understanding of the nodal nature of home and the importance of rootedness all had consequences in determining whether investment was efficient. This study lends weight to the case for including ‘meaning of home’ factors routinely in housing research.     

The food-service industry, dietary guidelines and change

This study was aimed at assessing the clinical usefulness of measuring the contrast enhancement (CE) of solitary pulmonary nodules (SPN) in distinguishing benign from malignant lesions. We used spiral CT to study prospectively 35 pulmonary lesions presenting as SPNs < 30 mm phi; we evaluated the CE of the nodules 120 minutes after the administration of 100 mL of nonionic contrast material (= 30 grams of iodine), at 2 mL/s. The final diagnosis of the 35 SPNs was made at surgery (27 cases); positive sputum cytology (2 cases), 12 months' follow-up (5 cases) or fine-needle aspiration biopsy and 6 months' follow-up (1 case). Thus, 25 of 35 SPNs proved malignant (11 adenocarcinomas, 5 squamous cell carcinoma, 2 large cell carcinomas, 2 carcinoids, 1 small cell carcinoma, 2 cases with positive sputum cytology, 2 metastases) and the extant 10 of 35 proved benign. Malignant nodules enhanced markedly more (mean value: 36.8 HU) more than benign lesions (mean value: 18.6 HU). CE exceeded 20 HU in 23/25 malignant nodules and did not in 2/25; it did not exceed 20 HU in 6/10 benign nodules and did in 4/10. With 20 HU as the threshold value for a positive test (malignancy), sensitivity was 92%, specificity 60% and accuracy 83%; positive and negative predictive values were 85% and 75%, respectively. In conclusion, CE evaluation is a sensitive, although not very specific, indicator of malignancy in SPNs.     

Accountability and ecological sustainability challenges under NPM-based public sector-led urban development: four international comparative cases

This paper compares four different public sector-led urban development institutional arrangements within New Public Management (NPM)’s framework. The cases come from three European countries – Sweden, Finland and the Netherlands – and the Australian state of Victoria. These four jurisdictions, though distant, share much in terms of urban development processes and actors’ responsibilities within these processes, as well as legislation concerning urban development. In the comparison, emphasis is placed on addressing public accountability and ecological sustainability. Ecological sustainability is important to the public sector and urban development has a significant role in achieving more ecologically sustainable built environments. It was found out that steering the development projects is relevant to sustainability issues. Accountability needs to be addressed when forming single-purpose organizational arrangements, but the paper concludes that the examined organizations have no flaws in accountability. In examining these cases, it is assumed that all four operate in governance environments dictated by NPM’s methods, and their success is thus evaluated in that framework. There is little evidence so far of international comparative urban development research combining values and results achieved; or comparing cases from different jurisdictions.