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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

How effective are primary care pharmacists at running dyspepsia clinics for patients prescribed PPIs?

Petty, Duncan R., Allan, J., Dawson, R., Silcock, Jonathan 10 October 2018 (has links)
Yes / Introduction As a consequence of the low cost and perceived safety, proton pump inhibitors (PPIs) are widely prescribed but they can cause longterm adverse effects and are often overprescribed. For most patients PPIs should not be continued long-term as patients can become dependent on PPIs and they are rarely stepped down/off treatment. We aimed to measure whether a dyspepsia review service could help patients on PPIs to step down/off treatment whilst still keeping them symptom free. Methods Pharmacists were provided with training on dyspepsia management. Four general practices were selected. Patients taking a PPI for more than two months were included. A list of exclusion criteria (e.g. active ulcers, newly initiated) was applied. Between six and eight dyspepsia review clinics were run at each site. Patients were booked into a 15-minute consultation. A concordance style consultation was held with clinicians providing information on dyspepsia management and exploring the patients’ ideas, concerns and expectations about stepping down or stepping off treatment. A follow-up audit was performed at four months to determine if patients had remained stepped down/off. An economic evaluation of clinic costs and drugs savings was performed. Results A total of 508 patients were invited to a review; 136 did not attend and 58 were excluded due to not meeting the inclusion criteria, leaving 314 patients reviewed for step-down/step-off. Successful step down/step off was achieved in 257 people (82% of those reviewed). The total cost savings of PPIs was £7,100. The additional cost of alginates was £1,207 giving a net saving on medicines of £5,893 per annum. Set-up costs were £1,194 and staff costs £3,524 to £5,156 giving total running costs, which vary dependent on the Agenda for Change (AfC) grade of pharmacist involved, of £4,720 - £6,351. Conclusion A dyspepsia review clinic is cost-neutral to run but, given that many patients are on polypharmacy, PPI step down might best be considered as part of a holistic medication review clinic. / Reckitt Benckiser, National Institute for Health Research, Health Education England
122

The Control of Multiple Actuators using Single IEHEC Pump/Motor

Bekele, Teshale, Åman, Rafael, Handroos, Heikki 28 April 2016 (has links) (PDF)
The awareness and concern of our environment together with legislation have set more and more tightening demands for energy efficiency of non-road mobile machinery(NRMM). Integrated electro- hydraulic energy converter (IEHEC) has been developed in Lappeenranta University of Technology (LUT) /1/. The elimination of resistance flow, and the recuperation of energy makes it very efficient alternative. The difficulties of IEHEC machine to step to the market has been the requirement of one IEHEC machine per one actuator. The idea is to switch IEHEC between two actuators of log crane using fast on/off valves. The control system architecture is introduced. The system has been simulated in co-simulation using Simulink/Mevea. The simulated responses of pumpcontrolled system is compared to the responses of the conventional valve-controlled system.
123

A Lumped Parameter Approach for GEROTOR Pumps: Model Formulation and Experimental Validation

Pellegri, Matteo, Vacca, Andrea, Devendran, Ram S., Dautry, Etienne, Ginsberg, Benjamin 28 April 2016 (has links) (PDF)
This paper describes a high fidelity simulation model for GEROTOR pumps. The simulation approach is based on the coupling of different models: a geometric model used to evaluate the instantaneous volumes and flow areas inside the unit, a lumped parameter fluid dynamic model for the evaluation of the displacing action inside the unit and mechanical models for the evaluation of the internal micro-motions of the rotors axes. This paper particularly details the geometrical approach, which takes into account the actual geometry of the rotors, given as input as CAD files. This model can take into account the actual location of the points of contact between the rotors as well for the actual clearances between the rotors. The potentials of the model are shown by considering a particular GEROTOR design. A specific test set-up was developed within this research for the model validation, and comparisons in terms of steady-state pressure versus flow curves and instantaneous pressure ripples are shown for the reference pump.
124

Thermally driven natural circulation water pump

Hobbs, Kyle 03 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The water utilized by passive air-conditioning systems in buildings is typically required at higher elevations. The thermally driven natural circulation water pump (TDNCWP) is a passively driven pumping system for delivering water from ground level against gravity to a higher elevation. It consists of a humid air closed duct loop to which a temperature difference is applied, resulting in a density gradient driven flow. A hot water evaporation tray inside the loop at ground level introduces water vapour to the loop air flow, and a cold condensation plate inside the loop at the elevated level removes this water vapour for passive airconditioning usage. In this thesis, a one-dimensional theoretical and numerical simulation model is developed. Experiments were conducted on two experimental TDNCWP set-ups of different cross sectional areas to evaluate the pump design and the theoretical model. It is shown in this thesis that the TDNCWP can provide water at varied elevations using non-mechanical, passive means. A temperature difference of 9 to 12.5 °C induced an average velocity of 0.4 to 0.6 m/s for a duct cross section of 100 mm2. For a larger cross section of 400 mm2, a temperature difference of 2 to 5 °C induced an average velocity of 0.25 to 0.3 m/s. An asymmetrical velocity profile was observed which varied at different points in the loop. A water delivery rate of 1.2 to 7.5 L/day was experimentally determined which compares well to the passive air-conditioning water requirements of a small building. The theoretical model over-predicted the delivery rate at increased duct cross sectional areas but fared well when compared to the smaller experimental model results. Further refinement of the numerical model and the TDNCWP design is required, and recommendations were made regarding this. It is clear however that the TDNCWP provides an alternative to a conventional water pump for low-volume water pumping requirements. / AFRIKAANSE OPSOMMING: Die water wat gebruik word deur passiewe lugversorgingstelsels in geboue word tipies benodig op hoër vlakte. Die termies gedrewe natuurlike sirkulasie waterpomp (TDNCWP) is ʼn passiewe gedrewe pomp stelsel vir die lewering van water vanaf die grondvlak teen swaartekrag na ʼn hoër vlak. Dit bestaan uit 'n vogtige geslote lug geut siklus waarop ʼn temperatuur verskil toegepas word, dit lei tot vloei gedrewe deur ʼn digtheids gradiënt. ʼn Warm water verdampings-pan binne die geut op grondvlak stel waterdamp aan die geut lugvloei toe, en ʼn koue kondensasie plaat binne die geut op die verhoogde vlak verwyder hierdie waterdamp vir passiewe lugversorgings gebruik. In hierdie tesis word ʼn eendimensionele teoretiese en numeriese simulasie model ontwikkel. Eksperimente is uitgevoer op twee eksperimentele TDNCWP stelsels van verskillende deursnee grootes om die pomp ontwerp en die teoretiese model te evalueer. Die tesis dui aan dat die TDNCWP water kan voorsien teen verskillende hoogtes op ʼn nie-meganiese, passiewe wyse. ʼn Temperatuur verskil van 9 tot 12.5 °C veroorsaak ʼn gemiddelde snelheid van 0.4 tot 0.6 m/s vir ʼn geut deursnit van 100 mm2.Vir ʼn groter deursnit van 400 mm2, het ʼn temperatuur verskil van 2 tot 5 °C ʼn gemiddelde snelheid van 0.25 tot 0.3 m/s veroorsaak. ʼn Asimmetriese snelheidsprofiel was waargeneem wat gewissel het op verskillende punte in die siklus. ʼn Water voorsienings tempo van 1.2 tot 7.5 L / dag was eksperimenteel waargeneem wat goed vergelyk met die passiewe water lugversorging vereistes van 'n klein gebou. Die teoretiese model het ʼn groter voorsienings tempo voorspel vir die groot deursneë, maar het goed gevaar in vergelyking met die kleiner eksperimentele model. Verdere verfyning van die numeriese model en die TDNCWP ontwerp word vereis, en aanbevelings is gemaak ten opsigte van hiervan. Dit is egter duidelik dat die TDNCWP ʼn alternatief is vir konvensionele lae-volume water pomp applikasies. / National Research Foundation (NRF)
125

A technical and economic feasibility study for the integration of GSHP technology in the Christchurch rebuild

Bustard, Samuel Kent January 2014 (has links)
Mr Wayne Tobeck, Director of Southrim Group (SRG), sponsored this 2013 MEM Project titled; A Technical and Economic Feasibility Study for the Integration of GSHP Technology in the Christchurch Rebuild. Following the recent Christchurch earthquakes, a significant amount of land has become too unstable to support traditional building foundations. This creates an opportunity to implement new and unique foundation designs previously unconsidered due to high costs compared to traditional methods. One such design proposes that an Injection Micro-Piling technique could be used. This can also be coupled with HVAC technology to create a Ground Source Heat Pump (GSHP) arrangement in both new buildings and as retrofits for building requiring foundation repair. The purpose of this study was to complete a feasibility study on the merits of SRG pursuing this proposed product. A significant market for such a product was found to exist, while the product was also found to be technically and legally feasible. However, the proposed product was found to not be economically feasible with respect to Air Source Heat Pumps due to the significantly higher capital and installation costs required. Further analysis suggests GSHPs may become more economically attractive in operating temperatures lower than -9oC, though the existence of markets with this climate in NZ has not been studied. It is therefore suggested that SRG do not proceed with plans to develop a GSHP coupled foundation solution for the Christchurch rebuild.
126

Development of Components for a Heat Recycling Shower System

Cox, Astrid January 2016 (has links)
Given the unstable state of the environment, there is an undeniable need for the development of sustainable technologies. This need affects all areas of everyday life, even the shower. Modern shower systems result in energy waste in the form of heat, which can be minimized through the implementation of a heat exchanger. In cooperation with Consat SES this project developed a system to implement a heat exchanger using an in-shower water transportation pipe. A fitting non-electrical pump and motor were also chosen. To develop these elements a general design methodology of defining the problem, identifying the solution space, developing concepts, testing concepts and proposing a design, was used with adaptations for the component at hand. By following this strategy for each component and then reviewing the system as a whole, a new shower system was developed with a trapezoidal water transport pipe, a wing pump, and a turgo turbine.
127

Development of a computer program for general use in the design of solar powered water pumping systems

Denny, Ernest Edward 05 1900 (has links)
M. Tech. (Electrical Engineering, Faculty of Engineering) Vaal University of Technology) / Water is one of the basic necessities of life. In addition to being essential for the maintenance of life, this basic resource is a crucial requirement for combating poverty, hunger and disease in South African communities. In excess of twenty-nine percent of South African households do not have water in either their dwellings, or on site (source: 2005 RSA census data). This study documents an engineering solution to the problem of water pumping, utilising renewable energy (solar power) and readily available pumping hardware, configured via a structured design process. Resultant from the research, a software application has been developed that facilitates the design of solar (photovoltaic) powered water pumping applications. The selected design configuration of a nontracking, stand-alone, directly coupled system provides for the most robust and least complex design possible, making it imminently suitable for application in rural African conditions. Operation of the program is via a simple graphical user interface, with full and context sensitive help provided. It is tailored for use in Southern Africa and is provided with comprehensive databases of location dependant design information such as solar radiation, meteorology and magnetic declination data, together with expandable databases of pre-configured pump and solar panel hardware specification data. The program is manufacturer and component independent, with no affiliations in the choice of hardware. Design methodologies, together with a component matching strategy. Optimisation is achieved by a quantitative and efficiency 'best fit' analysis of the selected hardware components within the design context. Design output predictions are tabulated and graphed by month for a period of one year, allowing design visualisation. The application has been named 'South African Stand-alone Solar (PV) Water Pumping Design Aid', abbreviated as 'SAS-SWP' in its run-time form. The SASSWP application is illustrated in the functional overview provided in Figure 1. / VUT
128

Design and Development of a Lubrication Pump for a Horizontally Mounted Air-Conditioning Compressor.

Gilbert, Kenneth T. 01 December 2003 (has links)
Horizontally mounted compressors offer the advantage of reduced height in central air-conditioning units but prove difficult to produce economically due to costs associated with the manufacture of acceptable lubrication systems for the compressors. This study develops an effective, affordable oil pump for use on a horizontal compressor. Concepts are proven through testing of prototype assemblies. Test results drive modifications for future prototypes, and prototypes demonstrating adequate performance are modified for ease of manufacture. Research in this study proves that the most suitable design results from a modification of a rotating vane pump. The pump’s modifications enable it to pump oil in the same direction, regardless of the direction of shaft rotation and to prime itself when totally dry of oil. However, extensive use of horizontal compressors hinges upon the development of a satisfactory suspension system.
129

The insulin pump for you(th)

Lind, Jenny, Hedlund, Niclas, Löfberg, Jeanette January 2006 (has links)
<p>Detta projekt är ett examensarbete på 15 poäng inom Innovations och Designingenjörsprogrammet på Karlstads Universitet, utfört under våren 2006.</p><p>Målsättningen med projektet var att hitta en form på insulinpumpen som tilltalar unga användare och dessutom minskar känslan av medicinskt hjälpmedel. Vi bestämde oss för att ge den ett utseende som mer liknar annan teknisk utrustning som finns på markanden idag. Detta som en väg att försöka höja ungdomars motivering till att övervaka och behandla sin diabetes.</p><p>Vid intervjuerna framkom det att många unga hade problem med bärandet av pumpen. Dagens pump upplevs för stor och klumpig eftersom de ofta vill gömma den i/under kläderna. Som ett resultat av denna information så valde vi att dela pumpen i två mindre enheter. Pumpenheten, som är kopplad till kroppen, kan liknas vid en MP3-spelare, och fjärrkontrollen, som innehåller den mesta intelligensen, både ser ut som och fungerar som en armbandsklocka.</p><p>Klockan har också inbyggd kontinuerlig övervakning av blodsockervärdet utan stick. Vilket var ett av de vikigaste önskemålen från användarna.</p><p>Med detta koncept kan ungdomarna välja om de vill dölja pumpen, eftersom den är så pass liten, eller om de vill ha den synlig, eftersom den ser ut som annan teknisk utrustning som bärs på kroppen.</p> / <p>This project is an examination project for 15 points at the Innovation and design engineering program, carried out at Karlstad University during spring 2006.</p><p>The purpose of this project is to find a shape that addresses young people and to minimize the medical aid stamp of the pump. We decided to give the pump an appearance more similar to other electronic devices on the market today in order to increase the motivation of treating and monitoring your diabetes.</p><p>During the interviews we found out that, youngsters hade problems related to the pump carrying. The pump of today is a bit too big and clumsy for young people who often want to hide it. As a result of this information we divided the pump into two smaller units. The pump unit that is connected to the body looks a bit like an MP3 player, and the remote control, where the intelligence lies, both looks and works like a watch.</p><p>The remote also has integrated glucose monitoring that is non-invasive. This was one of the top priorities on the wish list of the users.</p><p>With this concept the youngsters can choose whether they want to hide it, since it is small enough to hide in the pocket, or to show it off for their friends, as it could pass for a portable device.</p>
130

Enhancing geothermal heat pump systems with parametric performance analyses

Self, Stuart 01 April 2010 (has links)
Parametric performance analyses and comparison of a basic geothermal heat pump, a heat pump cycle with motor cooling/refrigerant preheating, and a heat pump cycle utilizing an economizer with respect to first law is conducted through simulation. Changing compressor, pump, and motor efficiency, along with condenser pressure, evaporator pressure, degree of subcooling at the condenser exit and degree of superheating at the evaporator exit is investigated. Economizer arrangements yield the highest coefficient of performance and resilience to change in COP with variation in evaporator pressure, and degree of superheating and subcooling. The basic vapor compression and motor cooling/refrigerant preheating systems have the lowest COP throughout and greatest resilience to variation in compressor efficiency, motor efficiency and condenser pressure. Motor cooling/refrigerant preheating and economizers have advantages over basic vapor compression cycles. Motor cooling reduces ground loop heat exchanger length with similar COP, and economizers allow for an increase in COP compared to the basic cycle. / UOIT

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