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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.
281

Nodal Resistance Measurement System

Putta, Sunil Kumar 05 1900 (has links)
The latest development in the measurement techniques has resulted in fast improvements in the instruments used for measurement of various electrical quantities. A common problem in such instruments is the automation of acquiring, retrieving and controlling the measurements by a computer or a laptop. In this study, nodal resistance measurement (NRM) system is developed to solve the above problem. The purpose of this study is to design and develop a compact electronic board, which measures electrical resistance, and a computer or a laptop controls the board. For the above purpose, surface nodal points are created on the surface of the sample electrically conductive material. The nodal points are connected to the compact electronic board and this board is connected to the computer. The user selects the nodal points, from the computer, between which the NRM system measures the electrical resistance and displays the measured quantity on the computer.
282

Avaliação in vivo da precisão de localizadores foraminais preservando o coto periodontal /

Cury, Marina Tolomei Sandoval. January 2019 (has links)
Orientador: Eloi Dezan Junior / Banca: Gustavo Sivieri de Araújo / Banca: Rodrigo Ricci Vivan / Resumo: O objetivo deste trabalho foi avaliar in vivo a precisão dos localizadores foraminais Root ZXII, E-PEX e FIND ao alcançarem o limite da constrição apical, preservando o coto periodontal ou atingindo o forame apical em biopulpectomia. Para o estudo foram selecionados 90 dentes unirradiculados indicados para exodontia de pacientes que consentiram com a pesquisa. Após teste de sensibilidade pulpar positivo, foi realizado o acesso à câmara pulpar e a exploração com uma lima K#15, sob isolamento absoluto. Seguido do preparo cervical e médio com Reciproc R25, uma lima #15 foi utilizada como instrumento padrão para a odontometria, introduzida no canal, formando 2 grupos: inserção da lima até o limite da constrição apical (marca 0.5); e inserção da lima até o forame (marca 0.0) e recuar até a constrição (marca 0.5), sem remover a lima do canal. A lima foi estabilizada pelo preenchimento do canal com resina tipo flow e após fotopolimerização teve sua haste metálica cortada. Após a exodontia, os dentes foram imersos em hipoclorito de sódio 5,25% por 10 minutos para remoção de tecidos orgânicos remanescentes e então armazenados em solução fisiológica. Os dentes foram escaneados em microtomógrafo SkyScan 1272, com o auxilio do software CTAN, e realizada medida da ponta da lima ao centro da constrição e do forame apical, fornecendo dados para análise comparativa. Houve diferença estatística em detectar a constrição, após alcançar o forame, onde RootZX II mostrou maior precisão (P<0.05). C... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Abstract: This research evaluated, in vivo, the accuracy of Root ZXII, E-PEX and FIND foramen locators at the apical constriction limit, preserving the periodontal stump or until the apical foramen in biopulpectomy. For this study, 90 single-rooted teeth with extraction indication and patients' consent were selected. After positive pulpal cold sensitivity test, pulp chamber access was performed and a hand file K#15 was used to explore orifice entrance, under rubber dam. After cervical and middle instrumentation with Reciproc R25, the K#15 file was used as a standard instrument to determine working length, introduced in the root canal, forming 2 groups: insertion of the instrument until the apical constriction limit (mark 0.5); and insertion of the instrument until the foramen (mark 0.0) and repositioning at constriction (mark 0.5), without removing the file from the canal. The hand file was stabilized inside the canal with a light-cured flow resin and, after polymerization, the metal handle was cut. After extraction, teeth were immersed in 5.25% sodium hypochlorite for 10 minutes to remove remaining organic tissues and then stored in saline. The samples were analyzed through microCT SkyScan 1272, with CTAN software, which evaluated the proximity between the tip of the file to the apical constriction, providing data for comparative analysis. There was a statistical difference in detecting the constriction after reaching the foramen, where Root ZX II showed elevated accuracy (P... (Complete abstract click electronic access below) / Mestre
283

Extended-Use ECG Monitor

Soski, Daniel Aaron 01 June 2018 (has links)
In this thesis, a prototype ECG monitor was developed that is integrated into an elastic shirt and takes a 3-lead ECG for over 5 days. The high-quality measurements can be used to identify markers indicative of various detrimental heart conditions. Measurements recorded by the device are encrypted and stored onto a micro-SD card. Current Holter monitors are expensive and have functional lives less than 48 hours; however, extended duration monitoring has been proven more useful in diagnosis. The device designed demonstrates that ECG measurements can be taken over longer durations without sacrificing quality, comfort, or device cost.
284

Stationary Exercise Bicycle Instrumentation and Verification of OpenSim Pelvic Residual Loads in Seated Cycling

Wash, Bradley Robert 01 June 2019 (has links)
The study of cycling biomechanics typically requires measurement of pedal loads through force transducer instrumentation. However, analysis of seated cycling often necessitates the additional measurement of the loads exerted on the rider by the seat and handlebars. A stationary exercise bicycle was instrumented with two commercial six-axis force transducers at both the seat and handlebar locations via a custom designed mounting system. The system was tested by applying known forces and moments to the fixtures and proved capable of accurately measuring the loads. Additional data collected from cycling tests were compared to values from the literature to add supporting evidence to the validity of the system. The instrumented stationary bicycle was further used to study the accuracy of modeling seated cycling in OpenSim. Five participants cycled at a moderate resistance level for three trials. Force and moment data were collected by seat, handlebar, and pedal load cells, while kinematic data were collected by an optical motion capture system. Participant data were analyzed with the OpenSim residual reduction algorithm (RRA) tool excluding seat and handlebar loads. The RRA pelvic residual was then compared to an experimentally determined handlebar and seat equivalent (HBSE) calculated from respective load cell data. Graphical comparisons of the RRA and HBSE results showed strong correlations in Anterior-Posterior (A-P) and Superior-Inferior (S-I) force directions and to a lesser degree, Medial-Lateral (M-L) force and S-I moment directions. M-L and A-P moment plots showed the least correlation between RRA and HBSE. Statistical comparisons showed RRA errors likely within 5.2% body weight (BW) for forces and 2.4% BW*height for moments. Considering the average participant height and weight of 167.7 cm and 63.6 kg, respectively, recommended error ranges for RRA are roughly ±4.0% BW for forces and ±7.2% BW*height for moments. This indicates that the OpenSim RRA tool can be used for cycling analysis.
285

An In Vitro comparison of three different techniques to create a glide path prior to nickel titanium rotary instrumentation

Cassim, Imran January 2013 (has links)
The preparation of a glide path prior to the use of rotary nickel titanium instrumentation reduces torsional stress and the risk of rotary nickel titanium instrument separation. The objective of this in vitro study was to evaluate 3 different glide path preparation techniques in respect of:  Percentage change of curvature from original canal anatomy; and  The occurrence of aberrations in canal anatomy (ledging, zipping and elbows). One hundred and twenty S-shaped Endo-Training-Blocks were selected. The canals were injected with India ink dye. The blocks were indexed with 3 bur marks and placed into a template before pre-instrumentation images were acquired digitally. The blocks were randomly divided into four groups of thirty each. Glide paths were prepared by a single operator with stainless steel hand K-files only, up to ISO size 20 (group 1, control), stainless steel hand K-files in the M4 reciprocating hand-piece up to ISO size 20 (group 2), hand K-files to ISO size 10 then NiTi rotary PathFiles (group 3) and hand K-files to ISO size 10 then NiTi rotary X-Plorer files (group 4). After glide path preparation the blocks were replaced into the template and post-instrumentation images were digitally acquired. Percentage change of curvature from original canal anatomy: Pre-instrumentation and post-instrumentation images were imported into Rhinoceros software to determine the end points of the canal curves and calculate the percentage change of canal curvature for the radii of apical and coronal curves. The data was collected and tabulated. Differences in canal curvature modification were statistically analysed with respect to logarithmic transformed change from baseline using ANCOVA (p<0.001) with logarithmic transformed pre-instrumentation values as covariate. After establishing preparation differences, both for change from baseline (pre-instrumentation) for apical and coronal curves, specific differences were tested using Fisher’s LSD for pairwise comparisons. Prepared groups differed significantly (p<0.001) and in particular, group 1 (Hand K-files) (control) and group 2 xiii (Hand K-files in M4 Safety reciprocating hand piece) differed significantly from all the other groups while group 3 (Hand K-files and PathFiles) and group 4 (Hand K-files and X-Plorer files) did not differ significantly. Group 3 (Hand K-files and PathFiles) and group4 (Hand K-files and X-Plorer files) were also superior to group1 (Hand K-files) (control) and group2 (Hand K-files in M4 Safety reciprocating hand piece). The occurrence of aberrations in canal anatomy (ledging, zipping and elbows): Pre-instrumentation and post-instrumentation images were superimposed using Adobe Photoshop software. The images were imported into a PowerPoint presentation and examined by three different blinded clinicians independently, for the presence of aberrations. There were no differences between the examiners in their assessment of the images. The data was collected and tabulated. The incidence of canal aberrations was analysed using Fisher’s exact test (p<0.05). The groups differed significantly regarding the number of aberrations (p=0.005). In particular, group 1 (control) (Hand K-files) and group 2 (Hand K-files in the M4 reciprocating hand piece) did not differ statistically (p=0.254; 20% and 6.67%). However group 2 (hand K-files in the M4 reciprocating hand piece) also did not differ significantly from group 3 (Hand K-files and PathFiles) and Group 4 (Hand K-files and X-Plorer files) (p=0.326). There were no aberrations detected in the rotary NiTi groups (group 3 and group 4). / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Odontology / unrestricted
286

Assessment of Access Methods for Mobile Maps for Individuals Who are Blind or Visually Impaired

Parker, David 01 January 2019 (has links)
When people go to a mall, museums, or other such locations they tend to rely on maps to find their way around. However, for people who are blind or visually impaired (BVI) maps are not easily accessible and they depend on other means, such as a guide, to get around. Research has only just begun to investigate providing maps for people who are BVI on touch screen devices. Many different types of feedback have been used: audio (sound), tactile (touch), audio-tactile, and multitouch. Some research has been conducted on the benefit of using multiple fingers (multitouch) and has found conflicting results. Yet, no known research has been conducted on the comparison of using audio feedback to that of tactile feedback. In this study, we look to try and answer two questions. 1.) Is audio equal to or better than tactile? As well as: 2.) Does multiple fingers help? Participants were asked to use seven different methods (4 audio, 3 tactile) to explore an overview map and an individual map and answer questions about them. Results showed that overall, audio cues are similar or better than tactile cues which is beneficial since it requires less battery to generate audio cues than tactile cues. It was also shown that the use of multiple fingers was more beneficial in tasks that are spatially demanding. While those who have tactile experience benefited when using two fingers with each finger represented by a different instrument played to separated ears.
287

4. Workshop "Measurement techniques for stationary and transient multiphase flows", Rossendorf, November 16 - 17, 2000

Prasser, Horst-Michael January 2001 (has links)
In November 2000, the 4th Workshop on Measurement Techniques for Stationary and Transient Multiphase Flows took place in Rossendorf. Three previous workshops of this series were national meetings; this time participants from different countries took part. The programme comprised 14 oral presentations, 9 of which are included in these proceedings in full length. A special highlight of the meeting was the main lecture "Ultrasonic doppler method for bubbly flow measurement" of Professor Masanori Aritomi, Dr. Hiroshige Kikura and Dr. Yumiko Suzuki, which was read by Dr. Hiroshige Kikura. The workshop again dealt with high-resolution phase distribution and phase velocity measurement techniques based on electrical conductivity, ultrasound, laser light and high-speed cinematography. A number of presentations were dedicated to the application of wire-mesh sensors developed by FZR for different applications used by the Technical Universities of Delft and Munich and the Tokyo Institute of Technology. The presentations were in particular: M. Aritomi, H. Kikura, Y. Suzuki (Tokyo Institute of Technology): Ultrasonic doppler method for bubbly flow measurement V. V. Kontelev, V. I. Melnikov (TU Nishny Novgorod): An ultrasonic mesh sensor for two-phase flow visualisation A. V. Duncev (TU Nishny Novgorod): Waveguide ultrasonic liquid level transducers for power generating equipment H.-M. Prasser, E. Krepper, D. Lucas, J. Zschau (FZR), D. Peters, G. Pietzsch, W. Taubert, M. Trepte (Teletronic Ingenieurbüro GmbH), Fast wire-mesh sensors for gas-liquid flows and decomposition of gas fraction profiles according to bubble size classes D. Scholz, C. Zippe (FZR): Validation of bubble size measurements with wire-mesh sensors by high-speed video observation A. Manera, H. Hartmann, W.J.M. de Kruijf, T.H.J.J. van der Hagen, R.F. Mudde, (TU Delft, IRI): Low-pressure dynamics of a natural-circulation two-phase flow loop H. Schmidt, O. Herbst, W. Kastner, W. Köhler (Siemens AG KWU): Measuring methods for the investigation of the flow phenomena during external pressure vessel cooling of the boiling water reactor SWR1000 A. Traichel, W. Kästner, S. Schefter, V. Schneider, S. Fleischer, T. Gocht, R. Hampel (HTWS Zittau/Görlitz - IPM): Verification of simulation results of mixture level transients and evaporation processes in level measurement systems using needle-shaped probes S. Richter, M. Aritomi (Tokyo Institute of Technology): Methods for studies on bubbly flow characteristics applying a new electrode-mesh tomograph
288

The Klezmer Influence in Paul Schoenfield’s Klezmer Rondos

Trimble, Mark 12 1900 (has links)
Paul Schoenfield’s Klezmer Rondos is a work for flute, male vocalist, and orchestra revised in 1994 according to the score given to me by the composer. A review of current research in klezmer heritage music is the starting point to place Klezmer Rondos in the context of art music infused with klezmer flavor. Klezmer music can be defined as the instrumental folk music of Eastern European Jews, however because of its adaptability and quality of assimilating other cultures within it, this heritage music is constantly in flux. By looking at the research in this field, I describe how the sound of klezmer music has evolved and how popular notions have been formed. The body of this research explores the main musical aspects of Klezmer Rondos that can be tied to the klezmer tradition: scales and thematic materials, improvisatory elements, ornamentation, and instrumentation. Klezmer Rondos moves beyond a simple arrangement of vernacular music for orchestra; it is a fusion of contemporary art music with the elements of klezmer style.
289

Designing an Instrument Based nn Native Fluorescence to Determine Soil Microbial Content at a Mars Analog Site

Smith, Heather D. 01 December 2009 (has links)
For this research project we designed an instrument to detect bacteria via biomolecular fluorescence. We introduce the current understanding of astrobiology, our knowledge of life beyond Earth, and the commonality of Earth life as it pertains to the search for life on Mars. We proposed a novel technique for searching for direct evidence of life on the surface of Mars using fluorescence. We use the arid region of the Mojave Desert as an analog of Mars. Results indicate the fluorescence of the biotic component of desert soils is approximately as strong as the fluorescence of the mineral component. Fluorescence laboratory measurements using the portable instrument reveal microbial concentration in the Mojave Desert soil is 107 bacteria per gram of soil. Soil microbial concentrations over a 50 meter area in the Mojave Desert, determined in situ via fluorescence, show that the number varies from 104 to 107 cells per gram of soil. We then designed an instrument for detection of biomolecular fluorescence, and considered also fluorescence from polycyclic aromatic hydrocarbons and minerals on the Martian surface. The majority of the instrument is designed from Mars surface operation flight qualified components, drastically reducing development costs. The basic design adapts the ChemCam instrument package on-board Mars Science Laboratory rover Curiosity to detect organics via fluorescence. By placing frequency multipliers in front of the 1064 nm laser, wavelengths suitable for fluorescence excitation (266 nm, 355 nm, and 532 nm) will be achieved. The emission system is modified by the addition of band pass filters in front of the existing spectrometers to block out the excitation energy. Biomolecules and polycyclic aromatic hydrocarbons are highly fluorescent at wavelengths in the ultra violet (266 nm, 355 nm), but not as much in the visible 532 nm range. Preliminary results show minerals discovered, such as perchlorate, fluoresce highest when excited by 355 nm. Overall, we conclude the fluorescent instrument described is suitable to detect soil microbes, organics, biomolecules, and some minerals via fluorescence, offering a high scientific return for minimal cost with non-contact applications in extreme environments on Earth and on future missions to Mars.
290

Adequacy of the cold chain used for the storage of heat-sensitive pharmaceuticals in a department of anaesthesiology

Boy, Graham Anthony January 2019 (has links)
A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Medicine in the branch of Anaesthesiology Johannesburg, 2019 / Background Anaesthesia frequently involves administration of refrigerated intravenous drugs to patients. Often overlooked, maintenance of the cold chain forms a key component of pharmacovigilance for anaesthetists. However the South African national Department of Health guidelines on: “Cold Chain and Immunisation Operations Manual”, does not detail specific requirements for medically validated cold boxes. Consequently the risk of iatrogenic harm to patients from heat-sensitive pharmaceuticals in inappropriately temperature regulated cold boxes exists. Methods The research design was that of a descriptive, prospective and contextual study. Part I study population comprised the ambient air temperatures of the refrigerator and cold boxes used for storage of heat-sensitive pharmaceuticals in theatre at CHBAH taken at one minute intervals over eight hours. Part II study population was newly purchased cold boxes and cold packs for the purpose of assessing individual cold box thermal performance over eight hours. Results In Part I, only a single cold box (polystyrene box number 19) was able to maintain the recommended temperature range of 2 − 8°C for the eight hour period (4.35%). The refrigerator temperature time plot showed a significant deviation of temperature at approximately 30 minutes. In Part II, only fabric and polystyrene cold boxes with three cold packs in situ were able to maintain the recommended temperature of 2 − 8°C. Conclusion This study highlighted the failure of non-medically validated cold boxes to reliably maintain the temperature of heat-sensitive pharmaceuticals. / E.K. 2019

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