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The successful demonstration of the “Aerostatic Seal” in a half scale rotating facility is described in this paper. The Aerostatic seal is a novel dynamic clearance seal specifically designed for steam turbine secondary gas path applications. The seal responds to radial rotor excursions, so a reduced clearance can be maintained compared to conventional labyrinth seal without damage to the seal. This enables increased turbine performance through reduced leakage and increased tolerance of turbine transient events typically found during start up. The seal is an extension of the existing retractable seal design already deployed in commercial steam turbines. The seal was tested in the Durham Rotating Seals Rig, which was developed specifically to test this device. The rig featured a rotor designed to run with large eccentricities to model high speed radial rotor excursions, and the seal was instrumented to measure the real time seal response to the rotor. The experimental campaign has conclusively demonstrated the ability of the seal to dynamically respond to the rotor position. The key result is that the seal is able to track the rotor position at high speed, and hence maintain a mean seal clearance that is lower than the rotor eccentricity. Overall this work marks a key milestone in the development of the Aerostatic Seal, and leads the way to testing in a steam environment and application in steam turbine plant.

The Good Practice Guidelines for the Assessment and Treatment of Adults with Gender Dysphoria is a publication of the Intercollegiate Committee of the Royal College of Psychiatrists. The overall goal of the Good Practice Guidelines is to provide clinical guidance for health professionals to assist transsexual, transgender, and gender nonconforming people with safe and effective pathways to achieving lasting personal comfort with their gendered selves, in order to maximize their overall health, psychological well-being, and self-fulfillment. This assistance may include primary care, gynaecologic and urologic care, reproductive options, voice and communication therapy, mental health services (e.g., assessment, counselling, psychotherapy), and hormonal and surgical treatments. The Good Practice Guidelines are based on the best available science and expert professional consensus. The Good Practice Guidelines articulate standards of care while acknowledging the role of making informed choices and the value of ...

This paper presents a series of experiments on the Aerostatic Seal, a dynamic clearance seal for steam turbine application first described at the 2015 ASME Turbo Expo (Paper Number GT2015-43471). This dynamic clearance seal moves with rotor excursions and so has the potential to deliver a smaller clearance than traditional seals. The concept is an extension of the retractable seal design which is widely used in existing steam turbines. The experimental program was carried out in a low cost static test facility using an aerostatic seal design. The seal exhibited a dynamic clearance response and will therefore respond to rotor excursions. 3D CFD was also used to aid the understanding of flow features not captured by the analytical design tool. Adjustments to both the design process and to future seal designs are proposed in the body of the paper. This paper therefore describes an experimental proof of concept for the aerostatic seal and paves the way for future development in rotating facilities.

Effective sealing in turbomachinery reduces the leakage flow bypassing the turbine blades and also reduces the losses where the leakage flow mixes with the primary flow. In general the clearance should be as small as possible but is limited by thermal and mechanical effects which vary with load. In recent years intermittent energy sources, particularly wind and solar, have appeared in greater numbers on the power network. As a consequence conventional power plants need to become more flexible to accommodate renewable energy generation. A sealing technology which can accommodate rapid changes in load and maintain seal performance would be a valuable development.This paper presents a novel seal design for steam turbines. The seal is designed to be capable of maintaining a smaller clearance than that of conventional labyrinth seals whilst allowing for dynamic movement with the rotor. The paper describes the seal concept and the analytic al work undertaken to demonstrate the concept. The seal design has also been tested in test facilities at Durham and the initial experimental results are included. They show that the concept works as intended.Copyright © 2015 by ASME and Alstom Technologie AG

This paper describes the design and optimization of an ‘air-curtain’ type seal using a fluidic jet to reduce tip leakage losses on a small high-speed single stage axial turbine device. The application will essentially demonstrate proof of concept for turbomachinery applications, opening the door for the development of future designs for applications in all scales of turbomachine. CFD is used to develop and optimize the seal design. The performance benefit from applying the new seal is predicted. These calculations illustrate the importance of accurately accounting for the effects of the sealing jet on shroud shear forces, in addition to leakage flow reduction, when determining the overall gain in turbine output power from the improved sealing. It is planned to validate the new seal design in full-scale turbine tests, during the next phase of the work.

Recommender systems gather user profile data either explicitly (users enter it) or implicitly (online behavior tracking).Surprisingly, given the prevalence of social media forums, which contain a rich set of user comments, there have been very few attempts to analyze the content of these comments to build up a user profile. In this paper, we compare and contrast a number of strategies for using text analysis to automatically gather profile data from user comments on news articles. We use this data to prototype a news recommender system based on the Guardian newspaper's 'Comment is Free' forum. The paper shows the feasibility of the approach: in a user study with fifty participants, our recommender outperforms a commercial 'best-in-class' system. Furthermore, we show that user comments allow recommender systems to track an evolving conversation related to a news article and can thus provide recommendations that better match the topics of conversation in comments, which maybe quite different from those in the original news article.

Our objective was to develop clinical practice guidance for the evaluation of hirsutism in premenopausal women. The Skin Academy is led by an international interdisciplinary team of experts, and aims to use the latest scientific and clinical data in selected dermatological diseases, to promote awareness, education and best clinical practice, thus improving patient care. The Skin Academy is an international platform designed to drive and develop education and awareness programmes, and to transfer scientific knowledge in dermatology across Europe and wider geographical areas. Consensus was guided by systematic review and discussion of current clinical practice across Europe during several group meetings of The Skin Academy, supported by conference calls, and e-mail communications. The outcome of the discussions was an evaluation form to be used by the clinician to help evaluate a patient presenting with excessive hair growth. This round-table expert opinion consensus paper, and the Diagnostic Evaluation Form it contains, is presented for discussion by the wider dermatology community.