157 resultados para thick ethical concept


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Boundary layer transition estimation and modelling is essential for the design of many engineering products across many industries. In this paper, the Reynolds-averaged Navier–Stokes are solved in conjunction with three additional transport equations to model and predict boundary layer transition. The transition model (referred to as the kTkT–kLkL–ωω model) is based on the kk–ωω framework with an additional transport equation to incorporate the effects low-frequency flow oscillations in the form of a laminar kinetic energy (kLkL). Firstly, a number of rectifications are made to the original kTkT–kLkL–ωω framework in order to ensure an appropriate response to the free-stream turbulence level and to improve near wall predictions. Additionally, the model is extended to incorporate the capability to model transition due to surface irregularities in the form of backward-facing steps with maximum non-dimensional step sizes of approximately 1.5 times the local displacement thickness of the boundary layer where the irregularity is located (i.e k/δ∗⪅1.5k/δ∗⪅1.5) at upstream turbulence intensities in the range 0.01<Tu(%)<0.80.01<Tu(%)<0.8. A novel function is proposed to incorporate transition sensitivity due to aft-facing steps. This paper details the rationale behind the development of this new function and demonstrates its suitability for transition onset estimation on a flat plate at zero pressure gradient.

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The REsearch on a CRuiser Enabled Air Transport Environment (RECREATE) project is considers the introduction and airworthiness of cruiser-feeder operations for civil aircraft. Cruiser-feeder operations are investigated as a promising pioneering idea for the air transport of the future. The soundness of the concept of cruiser-feeder operations for civil aircraft can be understood, taking air-to-air refueling operations as an example. For this example, a comprehensive estimate of the benefits can be made, which shows a fuel burn reduction potential and a CO2 emission reduction of 31% for a typical 6000 nautical miles flight with a payload of 250 passengers. This reduction potential is known to be large by any standard. The top level objective of the RECREATE project is to demonstrate on a preliminary design level that cruiser-feeder operations (as a concept to reduce fuel burn and CO2 emission levels) can be shown to comply with the airworthiness requirements for civil aircraft. The underlying Scientific and Technological (S&T) objectives are to determine and study airworthy operational concepts for cruiser-feeder operations, and to derive and quantify benefits in terms of CO2 emission reduction but also other benefits.

Work Package (WP) 3 has the objective to substantiate the assumed benefits of the cruiser/feeder operations through refined analysis and simulation. In this report, initial benefits evaluation of the initial RECREATE cruiser/feeder concepts is presented. The benefits analysis is conducted in delta mode, i.e. comparison is made with a baseline system. Since comparing different aircraft and air transport systems is never a trivial task, appropriate measures and metrics are defined and selected first. Non-dimensional parameters are defined and values for the baseline system derived.

The impact of cruiser/feeder operations such as air-to-air refueling are studied with respect to fuel-burn (or carbon-dioxide), noise and congestion. For this purpose, traffic simulations have been conducted.
Cruiser/feeder operations will have an impact on dispatch reliability as well. An initial assessment of the effect on dispatch reliability has been made and is reported.

Finally, a considerable effort has been made to create the infrastructure for economic delta analysis of the cruiser/feeder concept of operation. First results of the cost analysis have been obtained.

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The project REsearch on a CRuiser Enabled Air Transport Environment (RECREATE) is about the introduction and airworthiness of cruiser-feeder operations for civil aircraft. Cruiser-feeder operations are investigated as a promising pioneering idea for the air transport of the future.
The top level objective of the project is to demonstrate on a preliminary design level that cruiser-feeder operations (as a concept to reduce fuel burn and CO2 emission levels) can be shown to comply with the airworthiness requirements for civil aircraft. The project is funded through the Seventh Framework Programme of the European Commission. Work Package (WP) 1 has the objective to substantiate that viable and acceptable concepts for cruiser/feeder operations exist. In this deliverable the initial operational concept of the RECREATE cruiser/feeder is presented.

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Laser accelerated proton beams have been proposed to be used in different research fields. A great interest has risen for the potential replacement of conventional accelerating machines with laser-based accelerators, and in particular for the development of new concepts of more compact and cheaper hadrontherapy centers. In this context the ELIMED (ELI MEDical applications) research project has been launched by INFN-LNS and ASCR-FZU researchers within the pan-European ELI-Beamlines facility framework. The ELIMED project aims to demonstrate the potential clinical applicability of optically accelerated proton beams and to realize a laser-accelerated ion transport beamline for multi-disciplinary user applications. In this framework the eye melanoma, as for instance the uveal melanoma normally treated with 62 MeV proton beams produced by standard accelerators, will be considered as a model system to demonstrate the potential clinical use of laser-driven protons in hadrontherapy, especially because of the limited constraints in terms of proton energy and irradiation geometry for this particular tumour treatment. Several challenges, starting from laser-target interaction and beam transport development up to dosimetry and radiobiology, need to be overcome in order to reach the ELIMED final goals. A crucial role will be played by the final design and realization of a transport beamline capable to provide ion beams with proper characteristics in terms of energy spectrum and angular distribution which will allow performing dosimetric tests and biological cell irradiation. A first prototype of the transport beamline has been already designed and other transport elements are under construction in order to perform a first experimental test with the TARANIS laser system by the end of 2013. A wide international collaboration among specialists of different disciplines like Physics, Biology, Chemistry, Medicine and medical doctors coming from Europe, Japan, and the US is growing up around the ELIMED project with the aim to work on the conceptual design, technical and experimental realization of this core beamline of the ELI Beamlines facility. © 2013 SPIE.

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This study aims to report the analysis of the concept of vulnerability. Literature searches were conducted as well as a manual library search from article reference lists. Retrieved literature was analysed using the Walker & Advant (2005) concept analysis framework. The study concludes that inclusion of the concept of vulnerability within both pre- and post-registration training programmes would facilitate awareness of the issues surrounding perioperative vulnerability and the need to plan individualised care accordingly. It is hoped that this analysis will inspire further research and theoretical underpinning of perioperative practice, facilitating the development of new ways to manage vulnerability.

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Objective. To create, implement, and evaluate debate as a method of teaching pharmacy undergraduate students about ethical issues.

Design. Debate workshops with 5 hours of contact with student peers and facilitators and 5 hours of self-study were developed for second-year pharmacy students. Student development of various skills and understanding of the topic were assessed by staff members and student peers.

Assessment. One hundred fifty students completed the workshops. The mean score for debating was 25.9 out of 30, with scores ranging from 23.2 to 28.7. Seventy percent of students agreed that the debates were a useful teaching method in the degree program.

Conclusion. A series of workshops using debates effectively delivered course content on ethical issues and resulted in pharmacy students developing skills such as teamwork, peer assessment, communication, and critical evaluation. These findings suggest that pharmacy students respond favorably to a program using debates as a teaching tool.

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n 1953, noting a remarkable consistency between the agents causing mutations and those associated with cancer, Carl Nordling, a Finnish-born architect, proposed that cancer results from an accumulation of genetic mutations. It is now generally accepted that inherited mutations and environmental carcinogens can lead to the development of premalignant clones. After further mutations, one cell reaches a critical state which confers a survival or growth advantage over normal cells. Such cells have the ability to initiate a malignant tumour. They share many of the features of normal stem cells, including the capacity for self-renewal and differentiation, and are widely termed cancer stem cells (CSCs). Although CSCs have been well characterized in hematological malignancies, their existence in some other tissues has been questioned. Here, we review recent work in which stem cells and stem cell-like cells have been used to investigate the pathogenesis of cancer and potential anticancer treatment strategies, in the context of both hematological and somatic tissue disease.

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In this article, we propose a new way of approaching the topic of ethics for management and organization theory. We build on recent developments within critical organization studies that focus on the question of what kind of ethics is possible in organizational contexts that are inevitably beset by difference. Addressing this ‘ethics of difference’, we propose a turn to feminist theory, in which the topic has long been debated but which has been underutilized in organization theory until very recently. Specifically, we draw on the work of Bracha Ettinger to re-think and extend existing understandings. Inspired by gender studies, psychoanalysis, philosophy and art, Ettinger’s work has been celebrated for its revolutionary re-theorization of subjectivity. Drawing on a feminist ethics of the body inspired by psychoanalysis, she presents a concept of ‘trans-subjectivity’. In this, subjectivity is defined by connectedness, co-existence and compassion towards the other, and is grounded in what Ettinger terms the ‘matrixial borderspace’. An ethics of organization derived from the concept of the matrixial suggests that a different kind of ethical relation with the Other is possible. In this article, we demonstrate this through examining the issue of gender in the workplace. We conclude by outlining the implications of this perspective for rethinking ethics, embodiment and gender, and in particular for the development of a corporeal ethics for organization studies.