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The purpose of this paper is to evaluate the thermal and fluid dynamic behaviors of natural convection in a vertical channel‐chimney system heated symmetrically at uniform heat flux in order to detect the different fluid motion structures inside the chimney, such as the cold inflow from the outlet section of the chimney and the reattachment due to the hot jet from the channel, for different extension and expansion ratios of the adiabatic extensions.

The model is constituted by two‐dimensional steady‐state fully elliptic conservation equations which are solved numerically in a composite three‐part computational domain by means of the finite‐volume method.

Stream function and temperature fields in the system are presented in order to detect the different fluid motion structures inside the chimney, for different extension and expansion ratios of the adiabatic extensions. The analysis allows to evaluate the effect of the channel aspect ratio on the thermal and fluid dynamic behaviors on a channel‐chimney system and thermal and geometrical conditions corresponding to a complete downflow. Guidelines to estimate critical conditions related to the beginning of flow separation and complete downflow are given in terms of order of magnitude of Rayleigh and Froude numbers.

The hypotheses on which the present analysis is based are: two‐dimensional, laminar and steady‐state flow, constant thermophysical properties with the Boussinesq approximation. The investigation is carried out in the following ranges: from 100 to 100,000 for the Rayleigh number, from 5.0 to 20 for the aspect ratio, from 1.0 to 4.0 for the expansion ratio and from 1.5 to 4 for the extension ratio.

Thermal design of heating systems in different technical fields, such as in electronic cooling and in building ventilation and houses solar components, evaluation of heat convective coefficients and guidelines to estimate critical conditions related to the beginning of flow separation and complete downflow.

The paper is useful to thermal designers because of its evaluation of the thermal and velocity fields, correlation for the Nusselt number and guidelines criteria in terms of Rayleigh and Froude numbers to evaluate conditions of flow separation and complete downflow in natural convection in air for vertical channels‐chimney systems.

UNDERCARRIAGE design practice has been through several changes in the last few years; these have resulted in very much increased mechanical complication, fortunately accompanied by a decrease in weight, and it is interesting to consider the structural changes implied in these lower weights. (The trend is shown in FIG. 1 for airliner types; for some bomber aircraft it appears even more marked.)

De territorialization - a concept of territory where social, economic, and political space are not necessarily geographical has developed from the radical alterations brought about by rapid globalization. For the first time in history, cultural spaces are developing that have no tangible connection to geographical places. Conventional learning structures, teaching methods, and course content make it difficult for these educational institutions to operate effectively in this climate. To prosper, they must make decisions expeditiously and the development of new programs must take place quickly, seamlessly, and continuously.

More importantly, with the changes demanded by these processes, the classroom must truly become a global entity. In this paper, an argument is proposed that though the forces of globalization have radically changed our conception and use of space, its material manifestation is as important now more then ever to those training to be architects and designers. However, the old lecture hall and studio configuration must make way for a new type of reflexive space that allows disciplinary boundaries to become blurred and more flexible.

If this occurs, universities might again become bastions of critical thought illustrating possible types of alternative spaces and temporalities within our personal and communal lives. By cultivating spaces built on the imperatives of diversity and simultaneity, the monistic onslaught of the global network culture could be translated into a multitude of spaces and temporalities that add richness to the necessary social, political, and cultural aspects of our lives. Within architectural discourse, this call is doubly important because this type of individual will most affect the virtual/material interfaces that are become increasingly common as the effects of economic and technological transformations are felt on a global scale.

Effect of rocket and launcher design parameters on the maximum height obtainable in vertical flight. Comparison of costs for single‐ and two‐stage rockets. If efficiencies of around 100,000 ft./lb. payload/lb. propellent can be realized in practice, small solid propellent rockets should prove economical for routine meterological use.

This study aims to investigate the interrelationships and elasticities between the production of renewable energy (RE) and three key variables: oil prices, gross domestic product (GDP) and carbon dioxide (CO₂) emissions.

The research uses panel data and time-series analyses for 10 developed and 16 emerging countries for the period 1976–2018, to identify panel and country-specific elasticity of RE production and dynamic causal relationships between these variables. The study uses an autoregressive distributed lag model to determine the long- and short-run dynamics between RE production and the three variables in each country.

Results show a long-run elasticity between RE and GDP, and short-run dynamics between RE and oil prices and CO₂ emissions in the developed countries. Whereas in the emerging countries category, there were long-run relationships between RE and GDP, CO₂ emissions and oil prices.

Results of this study are in fact crucial and can be applied in the drafting of resilience policies to tackle energy vulnerability as well as sustainable growth. The study results will inform and guide governments on the right policies to stimulate RE production in their own countries in the interests of both their national security and sustainable development globally.

This paper attempts to contribute to the literature in at least two ways. First, research on identifying common determining factors, including socioeconomic factors, in both emerging and advanced economies is considerably scarce. Most of the previous research in this field has focused only on the absolute value of RE production in a particular geographical area. Second, many studies have focused on RE consumption. This research differs from them by focusing on the production of RE. Thus, the main contribution of this study is to fill these gaps. The study also presents novel empirical evidence to determine RE production elasticity from 26 countries.

Steps take in Brighton Health District, with the help of CASPE Research (Clinical, Accountability, Service Planning and Evaluation), to build and maintain an approach to Quality Assurance (QA) are described. The system is based on co‐ordination of — and assistance to — voluntary peer review by clinicians and other professionals. The joint work has two aspects: first, implementation of microcomputer‐assisted trials of QA in a small number of clinical departments and professional/ non‐medical departments which aim to provide a productive environment for development of new indicators of the quality of care, and systems for their use, that are practical and economic for local use in the NHS. Second, the indicators are provisionally evaluated, and, where successful, related to service planning and resource management in the district. Indicators that are successful in Brighton will also be tested in other districts where CASPE is working.

Over the last decade, Australian organisations have embraced total quality management (TQM) as an effective management philosophy. However, a recent report indicated that there is little evidence of leading Australian researchers working on quality and related areas. Moreover, the perception is that whatever research has been done, it is fragmented and at a low level. In the light of this we conducted an extensive literature search on TQM materials. Our purpose was to provide a systematic analysis of the TQM articles published by the Australian researchers or in the context of Australian organisations. Our analysis led us to conclude that the research has been unbalanced, focusing mainly on case studies and empirical research. Further research is necessary to develop conceptual underpinning and analytical models based on large empirical studies.

Members of an organization that had undergone revolutionary, punctuated equilibrium type change were asked to tell the story of that change. Senior managers tended to make sense of the change as discontinuous, while individual contributors tended to make sense of the change as incremental. Three theories of individual sense‐making; individual agency, personal relevance, and strategic perspective are developed to suggest why individuals made sense of these changes differently.