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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.
31

Perkutane transluminale Angioplastie komplexer infrapoplitealer Gefässläsionen bei kritischer chronischer Extremitätenischämie: Restenoserate und klinische Ergebnisse

Winkler, Bert 04 August 2014 (has links) (PDF)
Perkutane transluminale Angioplastie komplexer infrapoplitealer Gefässläsionen bei kritischer chronischer Extremitätenischämie: Restenoserate und klinische Ergebnisse
32

Optical Pointing System For Stratospheric Balloon-Borne Multi-Slit OSIRIS-DM

2015 January 1900 (has links)
The Optical Spectrograph and InfraRed Imaging System (OSIRIS) satellite instrument spearheaded by a team of researchers at the University of Saskatchewan has provided scientists with 13 years of information about the state of the atmosphere. The success of the mission has motivated further development of the technology in a next generation instrument called the Canadian Atmospheric Tomography System (CATS) to provide better spatial and spectral resolution through a successive satellite mission. This work details the development of a proof-of-concept prototype built to test the validity of the CATS optical design. This thesis project utilized the developmental model built for the OSIRIS mission. The major modification made to the instrument replaced the optical element that defines the instrument’s field of view. This new development transformed the original single line of sight utilized by the satellite based OSIRIS instrument into three separate fields of view, which increased the imaging capabilities of the instrument. The new system has improved spatial resolution by collecting spectral information from three separate regions in the atmosphere in a single exposure, as opposed to the single region imaged by the original system. The newly developed prototype was tested on the platform of a stratospheric balloon. This test platform offered the capabilities to make limb scattered measurements similar to those that are made by a satellite based instrument. However, from the balloon geometry, the instrument required an additional pointing system to redirect the line of sight over stratospheric tangent altitudes. The design and test of this pointing system is also detailed in this work.
33

The Upgrade, Calibration and Evaluation of the Multi-Slit OSIRIS-DM for Stratospheric Balloon Flight

2015 January 1900 (has links)
The development of remote sensing satellite-borne instrumentation for the study of the Earth’s atmosphere has provided an immense increase in our understanding of atmospheric trends and processes. The Canadian built OSIRIS satellite instrument uses the limb scatter technique to measure scattered sunlight for the retrieval of vertical profiles of atmospheric species such as ozone. Recently, the next generation instrument, CATS, based on the OSIRIS design, is under development to continue OSIRIS measurements into the future. One key optical design change for CATS is the ability to measure simultaneously over multiple fields of view. However, this new optical design concept needs to be tested and evaluated. To achieve this, a prototype slit plate was installed into the preflight developmental version of OSIRIS, called OSIRIS-DM, for testing in the laboratory and on a stratospheric balloon. In this thesis work, an evaluation of the performance of this multi-slit instrument was undertaken through laboratory calibrations and limb scatter measurement collection. The calibration process includes a wavelength registration, a spectral point spread function analysis, a relative calibration and an absolute calibration, all performed with laboratory equipment. Along with laboratory calibrations, this thesis work involved preparation for the stratospheric balloon mission including the development of a flight ready electronic control and communication system to operate OSIRIS-DM during the mission. The upgraded instrument was launched on September 19, 2014, and ascended to a stable float altitude of 36.5 km. The collected flight measurements were used to evaluate the calibrations and general instrument performance. Overall, the laboratory calibrations proved to be sufficiently accurate and the measurement collection produced multiple spectra that may be used for atmospheric analysis in the future. These results show that the multi-slit design of the slit plate produces an instrument that can be reliably calibrated and implemented for limb scatter measurement collection.
34

Perceptions of coronary artery disease and compliance in percutaneous transluminal coronary angioplasty patients

Nesler, Donna W. January 1988 (has links)
Thesis (M.S.)--University of Wisconsin-Madison, 1988. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves: 28-32).
35

The knowledge of critical care nurses regarding intra-aortic balloonpump counterpulsation therapy

Oosthuizen, Phillippus Johannes 01 1900 (has links)
Intra-aortic balloonpump (IABP) counterpulsation therapy is a volume displacement device designed to provide partial assistance to the left ventricle of the heart. Critical care nurses are expected to manage IABP therapy. It is therefore important that the critical care nurse has the knowledge to manage IABP therapy in a safe and therapeutic manner. The question arises: does the critical care nurse have the knowledge to manage IABP therapy? The purpose of this research study is to explore and describe the knowledge of the critical care nurse regarding the management of IABP therapy. The design of this research study is a quantitative, descriptive and contextual study, in which a sample survey was performed, using a questionnaire (based on a literature study) under controlled conditions. The knowledge of the majority of critical care nurses tested was found to be insufficient. Safe management guidelines and in-service training have been proposed to improve the situation. / lntra-aortiese ballonpomp (IABP) teenpulsasie terapie is 'n volume verplasings apparaat, antwerp om gedeeltelike ondersteuning aan die linker ventrikel van die hart te bied. Kritiekesorgverpleegkundiges is verantwoordelik vir die hantering van rASP terapie. Die vraag ontstaan: beskik die kritiekesorgverpleegkundige oor voldoende kennis rakende die hantering van IABP terapie? Die doel van hierdie studie is om die kennis van kritiekesorgverpleegkundiges te ondersoek en te beskryf rakende die hantering van IABP terapie. Die resultate van hierdie navorsingstudie dui daarop dat die meerderheid kritiekesorgverpleegkundiges wat getoets was oor onvoldoende kennis beskik ten opsigte van IABP terapie. Formulering van riglyne en indiensopleiding is aanbeveel om hierdie situasie te verbeter. Die navorsingsontwerp is kwantitatief, beskrywend en kontekstueel van aard, waartydens 'n gerieflikheidsteekproeftrekking gedoen is, met gebruik van 'n vraelys (gebasseer op 'n literatuurstudie) onder gekontrolleerde toestande. / Health Studies / M.A. (Nursing Science)
36

An Investigation of the Effectiveness of Polymer Based Materials for Radiation Shielding of Flight Vehicles

Driouche, Bouteina 11 August 2017 (has links)
The Earth’s upper atmosphere is suffused by radiation caused primarily by a bombardment of Cosmic Rays, as a result of which it is hazardous for human beings as well as sensitive electronic equipment on board flight vehicles. A series of ground based as well as airborne experiments were performed using Polylactic Acid (PLA), Acrylonitrile-Butadiene-Styrene (ABS) and High Impact Polystyrene (HIPS), in order to investigate the applicability of polymers that can meet today’s needs for lightweight, multifunctional, and cost efficiency in radiation shielding of electronic equipment. It was found that PLA at 8 mm thickness has an effectiveness of 66% against gamma radiation (i.e., it blocked 66% of the gamma radiation). Therefore, it was decided to proceed with a high altitude balloon experiment with an 8 mm thickness of PLA. The shield was demonstrated to be reasonably effective in attenuating radiation from cosmic rays.
37

A Design For A High Altitude Flight Test System

Wahlers, Kristen Erin 13 May 2006 (has links)
Small UAV?s and flight vehicles in other atmospheres such as Mars are characterized by low Reynolds numbers. Low Reynolds number airfoil testing has been difficult to achieve and there are few centers that can accomplish this task. This study is an effort to develop a flight test system that will enable low Reynolds number tests to be performed with a simple glider design. The concept is to develop a high altitude glider that will be transported to altitudes reaching 100,000 feet or more by a helium filled balloon. At altitude, the glider will be released and will perform flight experiments as it descends. This region of Earth?s atmosphere, ?near space? has the conditions desired for low Reynolds number testing as well as similar properties to the surface of Mars. With the knowledge gained from this experiment, a better understanding of accomplishing flight on Mars may be attained.
38

A Novel Device for Delivering Combined Partial Breast Irradiation and Partial Breast Hyperthermia

White, Todd A. 16 May 2012 (has links)
No description available.
39

Methods of interventional pediatric cardiology in treatment of congenital heart diseases: immediate and long-term results / Intervencinės pediatrinės kardiologijos metodai įgimtų širdies ydų gydymui: ankstyvieji ir vėlyvieji rezultatai

Čibiras, Sigitas Vladas 04 February 2010 (has links)
Objective - to assess possibilities and specific characteristics of pediatric cardiology in treatment of congenital heart diseases (CHD), to evaluate efficacy of curative per-catheter procedures by means of analysis of immediate and long-term results. Retrospective study. The data of 422 patients who underwent 467 CHD palliative-curative procedures during the period since 1971 till 2007 were analyzed. It was postulated that balloon atrial septostomy resulted in statistically significant increase of atrial septal defect, increase of arterial blood oxygen saturation and decrease of interatrial preasure gradient (PG). Balloon pulmonary valvulotomy (BPV) is one of the most common curative procedures; this procedure has an effect of marked decrease of pressure gradient between the right ventricle and right atrium; development of pulmonary artery valve insufficiency is the most common complication of this procedure. The long - term results of BPV are less positive when higher PG prior the procedure is present and residual PG after the procedure is 36mmHg and higher. It was postulated, that closure of small (less than 3 mm) persistent ductus arteriosus using Cook coils may compete with surgical treatment successfully. It was stated, that the efficacy of balloon angioplasties of aorta, caval veins and pulmonary artery branches is transient; treatment using stents is more effective. It was postulated, that closure of congenital and postsurgical anomalies connections using coils is... [to full text] / Disertacijos objektas yra nustatyti intervencinės pediatrinės kardiologijos galimybes ir ypatumus, gydant įgimtas širdies ydas (ĮŠY), įvertinti gydomųjų perkateterinių procedūrų efektingumą, remiantis ankstyvųjų ir vėlyvųjų rezultatų analize. Tai retrospektyvus tyrimas. Analizuoti 422 ligonių duomenys, kuriems 1971 - 2007 m. buvo atliekamos 467 įgimtų širdies ydų paliatyvinės - gydomosios procedūros. Nustatyta, kad po balioninės tarpprieširdinės pertvaros septostomijos, statistiškai reikšmingai padidėja prieširdžių pertvaros defektas, didėja arterinio kraujo įsotinimas deguonimi ir mažėja spaudimų skirtumas (SS) tarp prieširdžių. Balioninė plaučių arterijos valvuloplastika (BPV) yra viena iš dažniausiai taikomų gydomųjų procedūrų, jos efektas – ryškus SS tarp dešiniojo skilvelio ir plaučių arterijos (PA) sumažėjimas, o pagrindinė komplikacija – PA vožtuvo nesandarumo vystymasis. BPV vėlyvieji rezultatai blogesni, kai yra didelis SS prieš procedūrą, o po procedūros liekamasis SS ≥ 36mmHg. Nustatyta, kad mažų iki 3mm AAL kimšimas Cook spiralėmis gali sėkmingai konkuruoti su operaciniu gydymu. Rasta, kad aortos, tuščiųjų venų ir plaučių arterijos šakų balioninės plastikos efektas trumpalaikis, o gydymas stentais daug sėkmingesnis. Nustatyta, kad anomalinių įgimtų ir pooperacinių kraujagyslinių jungčių užkimšimas spiralėmis yra saugus ir efektyvus gydymo metodas.
40

Preliminary design of a modular high altitude balloon power distribution system

Nordqvist, Emil January 2020 (has links)
This thesis conducts research into different rechargeable battery technologies and their applicability to the high altitude balloon flights conducted at Esrange space center. The research focuses on the possible use of lithium ion batteries’, sodium ion batteries, nickel metal hydrate, and Metal hydridelithiumion batteries. Resulting in lithium ion batteries in 18650 cells being recommended. The thesis continues with a modular power distribution system architecture design. The system architecture is established with solarcharging capabilities, up to 1500W peak output power, over 600W continuous output power, multiple output voltages, more than six output channels, remote output power switching, and monitoring of power consumption. A prototype is built from this architecture on which limited testing is performed.The testing shines light on future improvements and displays proof of concept for some parts.

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