151,268 research outputs found

    Current economic and sensitivity analysis for ID slicing of 4 inch and 6 inch diameter silicon ingots for photovoltaic applications

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    The economics and sensitivities of slicing large diameter silicon ingots for photovoltaic applications were examined. Current economics and slicing add on cost sensitivities are calculated using variable parameters for blade life, slicing yield, and slice cutting speed. It is indicated that cutting speed has the biggest impact on slicing add on cost, followed by slicing yield, and by blade life as the blade life increases

    Two systems developed for purifying inert atmospheres

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    Two systems, one for helium and one for argon, are used for purifying inert atmospheres. The helium system uses an activated charcoal bed at liquid nitrogen temperature to remove oxygen and nitrogen. The argon system uses heated titanium sponge to remove nitrogen and copper wool beds to remove oxygen. Both use molecular sieves to remove water vapor

    A Fluid Dynamics Calculation of Sputtering from a Cylindrical Thermal Spike

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    The sputtering yield, Y, from a cylindrical thermal spike is calculated using a two dimensional fluid dynamics model which includes the transport of energy, momentum and mass. The results show that the high pressure built-up within the spike causes the hot core to perform a rapid expansion both laterally and upwards. This expansion appears to play a significant role in the sputtering process. It is responsible for the ejection of mass from the surface and causes fast cooling of the cascade. The competition between these effects accounts for the nearly linear dependence of YY with the deposited energy per unit depth that was observed in recent Molecular Dynamics simulations. Based on this we describe the conditions for attaining a linear yield at high excitation densities and give a simple model for this yield.Comment: 10 pages, 9 pages (including 9 figures), submitted to PR

    Speaker-normalized sound representations in the human auditory cortex

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    The acoustic dimensions that distinguish speech sounds (like the vowel differences in ā€œbootā€ and ā€œboatā€) also differentiate speakersā€™ voices. Therefore, listeners must normalize across speakers without losing linguistic information. Past behavioral work suggests an important role for auditory contrast enhancement in normalization: preceding context affects listenersā€™ perception of subsequent speech sounds. Here, using intracranial electrocorticography in humans, we investigate whether and how such context effects arise in auditory cortex. Participants identified speech sounds that were preceded by phrases from two different speakers whose voices differed along the same acoustic dimension as target words (the lowest resonance of the vocal tract). In every participant, target vowels evoke a speaker-dependent neural response that is consistent with the listenerā€™s perception, and which follows from a contrast enhancement model. Auditory cortex processing thus displays a critical feature of normalization, allowing listeners to extract meaningful content from the voices of diverse speakers

    A study of the social expectations and desires of psychiatric patients.

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    Includes 7 figures and 25 tables. Thesis (M.S.)--Boston Universit

    Some Post-Pliocene Buried Soils of Central United States

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    The conversation: developing confidence to provide end of life care in Salford nursing homes

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    The study was funded by the Burdett Trust for Nursing and partly by Salford Primary Care Trust. A realistic evaluation design was used to collect data using a range of approaches, from before and after surveys of confidence in delivering end of life care, to participant observation and interviews. A total of 43 people were interviewed involving both staff, residents and relatives. Key Messages a) Significant resources are needed to engage staff, residents and relatives/carers with the idea of advance care planning b) Care home staff are optimistic about involving residents and relatives in planning care at the end of life and some relatives become very involved in care c) Clearly registered nurses and other care home workers such as care assistants have different roles, but the overlap between these and the appropriate boundaries would benefit from further work d) Talking to residents and relatives about their feelings and wishes for care at the end of life remains especially difficult, but education and training in key skills and knowledge can engender both ability and motivation e) Care homes need strong and well-informed leadership in order to implement the Gold Standards Framework f) Placing a relative in a care home involves strain and an ability to compromise ā€˜thereā€™s no perfect placeā€™ g) Advance care planning can reduce the distress and the number of inappropriate hospital admissions, but is challenging in the face of staff rotation and out of hours medical staff being unpredictable h) The principles of the Gold Standards Framework are widely seen as sensible, but clinical challenges include diagnosing and predicting dying trajectories, especially in heart failure, chronic pulmonary disease and dementia i) A particular concern of staff is how to approach nutrition and hydration as frailty and death approach j) Communicating about diagnosis and especially prognosis with residents who lack capacity is an increasing problem k) Natural justice suggests that resources should be allocated to the general standardisation of a good quality of care at the end of life in ALL care homes whatever their Care Quality Commission ratin
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