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Portable distributed system software for microcomputers.January 1987 (has links)
by Kwan Kar Kin, Karl. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1987. / Bibliography: leaves 77-79. / Library's copy:Disk for circulation (3.5 in.)
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Integration of Bluetooth-enabled sensors into E-health application for home healthcare and monitoringGarcía Pérez, Agustín January 2008 (has links)
ABSTRACTnformation and telecommunication technologies have been used for medical applications for almost a century: the radio, the phone and the television have been used to provide medical assistance to remote areas like boats located in the sea, oil rigs and other isolated locations. This new use of ICT was given the name of Telemedicine. ISince the 90`s, health care systems have been looking for new ways and alternatives to provide health care than the traditional hospital centers. Information technologies and communication systems have been developed, especially with the deployment of Internet access to most of residential areas, and have brought health care to the electronic age; Carving a new term E-Health.Nowadays Telemedicine is used in several E-health applications for teleconsultation, telediagnosis, telemonitoring and has been successfully tested in teleradiology, telecardiology, teledermatology, telepsychiatry, etc. This technology is used in rural areas, health areas, prisons, home cares, emergencies, wars, etc.This project implements two different parts. The first one is an user application to measure weight and blood pressure from the patient using two Bluetooth-enable measurement devices: the UC-321PBT Precision Health Scale and UA-767PBT Blood Pressure Monitor. The second one implements a web server to store all patients reports with updated information in real time. This information can be consulted through a web page for medical staff in HL7 patient’s report format. / Uppsatsnivå: D
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Hand-portable Capillary Liquid Chromatography InstrumentationSharma, Sonika 01 December 2015 (has links)
This dissertation focuses on the development of hand-portable capillary liquid chromatography (LC) instrumentation. In this work, battery-operable nano-flow pumping systems (isocratic and gradient) were developed and integrated with portable UV-absorption detectors for capillary LC. The systems were reduced in size to acceptable weights and power usage for field operation. A major advantage of the pumps is that they do not employ a splitter, since they were specifically designed for capillary column use, thereby greatly reducing solvent consumption and waste generation. UV-absorption detectors were specifically designed and optimized for on-column detection to minimize extra-column band broadening. Initially, an isocratic nano-flow pumping system with a stop-flow injector was integrated with an on-column UV-absorption detector (254 nm). The pumping system gave excellent flow rate accuracy (<99.94%) and low percent injection carry-over (RSD 0.31%) suitable for quantitative analysis. Using sodium anthraquinone-2-sulfonate, the detector gave an LOD (S/N = 3) of 0.13 µM, which was 12 times lower than a commercial UV-absorption detector. Reversed-phase separations of a homologous series of alkyl benzenes was demonstrated. Further miniaturization of UV-absorption detection was accomplished using a 260 nm deep UV LED. The detector was small in size and weighed only 85 g (without electronics). No optical reference was included due to the low drift in the signal. Two ball lenses, one of which was integrated with the LED, were used to increase light throughput through the capillary column. Stray light was minimized by the use of a band-pass filter and an adjustable slit. Signals down to the ppb level (nM) were easily detected with a short-term noise level of 4.4 µAU, confirming a low limit of detection and low noise. The detection limit for adenosine-5'-monophosphate was 230 times lower than any previously reported values. Isocratic separations of phenolic compounds were performed using a poly(ethylene glycol) diacrylate monolithic capillary column. Finally, a novel nano-flow gradient generator integrated with a stop-flow injector was developed. Gradient performance was found to be excellent for gradient step accuracy (RSD < 1.2%, n = 4) and linear gradient reproducibility (RSD < 1.42%, n = 4). Separations of five phenols were demonstrated using the nano-flow gradient system. Efforts to develop a 405 nm laser diode-based UV-absorption detector for hemoglobin analysis were described.
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Development of a portable aerosol collector and spectrometer (PACS)Cai, Changjie 01 May 2018 (has links)
The overall goal of this doctoral dissertation is to develop a prototype instrument, a Portable Aerosol Collector and Spectrometer (PACS), that can continuously measure aerosol size distributions by number, surface area and mass concentrations over a wide size range (from 10 nm to 10 µm) while also collecting particles with impactor and diffusion stages for post-sampling chemical analyses.
To achieve the goal, in the first study, we designed, built and tested the PACS hardware. The PACS consists of a six-stage particle size selector, a valve system, a water condensation particle counter to measure number concentrations and a photometer to measure mass concentrations. The valve system diverts airflow to pass sequentially through upstream stages of the selector to the detectors. The stages of the selector include three impactor and two diffusion stages, which resolve particles by size and collect particles for chemical analysis. Particle penetration by size was measured through each stage to determine actual performance and account for particle losses. The measured d50 of each stage (aerodynamic diameter for impactor stages and geometric diameter for diffusion stages) was similar to the design. The pressure drop of each stage was sufficiently low to permit its operation with portable air pumps.
In the second study, we developed a multi-modal log-normal (MMLN) fitting algorithm to leverage the multi-metric, low-resolution data from one sequence of PACS measurements to estimate aerosol size distributions of number, surface area, and mass concentration in near-real-time. The algorithm uses a grid-search process and a constrained linear least-square (CLLS) solver to find a tri-mode (ultrafine, fine, and coarse), log-normal distribution that best fits the input data. We refined the algorithm to obtain accurate and precise size distributions for four aerosols typical of diverse environments: clean background, urban and freeway, coal power plant, and marine surface. Sensitivity studies were conducted to explore the influence of unknown particle density and shape factor on algorithm output. An adaptive process that refined the ranges and step sizes of the grid-search reduced the computation time to fit a single size distribution in near-real-time. Assuming standard density spheres, the aerosol size distributions fit well with the normalized mean bias (NMB) of -4.9% to 3.5%, normalized mean error (NME) of 3.3% to 27.6%, and R2 values of 0.90 to 1.00. The fitted number and mass concentration biases were within ± 10% regardless of uncertainties in density and shape. With this algorithm, the PACS is able to estimate aerosol size distributions by number, surface area, and mass concentrations from 10 nm to 10 µm in near-real-time.
In the third study, we developed a new algorithm–the mass distribution by composition and size (MDCS) algorithm–to estimate the mass size distribution of various particle compositions. Then we compared the PACS for measuring multi-mode aerosols to three reference instruments, including a scanning mobility particle sizer (SMPS), an aerodynamic particle sizer (APS) and a nano micro-orifice uniform deposit impactor (nanoMOUDI). We used inductively coupled plasma mass spectrometry to measure the mass of collected particles on PACS and nanoMOUDI stages by element. For the three-mode aerosol, the aerosol size distributions in three metrics measured with the PACS agreed well with those measured with the SMPS/APS: number concentration, bias = 9.4% and R2 = 0.96; surface area, bias = 17.8%, R2 = 0.77; mass, bias = -2.2%, R2 = 0.94. Agreement was considerably poorer for the two-mode aerosol, especially for surface area and mass concentrations. Comparing to the nanoMOUDI, for the three-mode aerosol, the PACS estimated the mass median diameters (MMDs) of the coarse mode well, but overestimated the MMDs for ultrafine and fine modes. The PACS overestimated the mass concentrations of ultrafine and fine mode, but underestimated the coarse mode. This work provides insight into a novel way to simultaneously assess airborne aerosol size, composition, and concentration by number, surface area and mass using cost-effective handheld technologies.
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Strength Performance Assessment in a Simulated Men’s Gymnastics Still Rings CrossDunlavy, Jennifer K., Sands, William A., McNeal, Jeni R., Stone, Michael H., Smith, Sarah L., Jemni, Monem, Haff, G. Gregory 01 March 2007 (has links)
Athletes in sports such as the gymnastics who perform the still rings cross position are disadvantaged due to a lack of objective and convenient measurement methods. The gymnastics “cross ”is a held isometric strength position considered fundamental to all still rings athletes. The purpose of this investigation was to determine if two small force platforms (FPs) placed on supports to simulate a cross position could demonstrate the fidelity necessary to differentiate between athletes who could perform a cross from those who could not. Ten gymnasts (5 USA Gymnastics, Senior National Team, and 5 Age Group Level Gymnasts) agreed to participate. The five Senior National Team athletes were grouped as cross Performers; the Age Group Gymnasts could not successfully perform the cross position and were grouped as cross Non- Performers. The two small FPs were first tested for reliability and validity and were then used to obtain a force-time record of a simulated cross position. The simulated cross test consisted of standing between two small force platforms placed on top of large solid gymnastics spotting blocks. The gymnasts attempted to perform a cross position by placing their hands at the center of the FPs and pressing downward with sufficient force that they could remove the support of their feet from the floor. Force-time curves (100 Hz) were obtained and analyzed for the sum of peak and mean arm ground reaction forces. The summed arm forces, mean and peak, were compared to body weight to determine how close the gymnasts came to achieving forces equal to body weight and thus the ability to perform the cross. The mean and peak summed arm forces were able to statistically differentiate between athletes who could perform the cross from those who could not (p < 0.05). The force-time curves and small FPs showed sufficient fidelity to differentiate between Performer and Non- Performer groups. This experiment showed that small and inexpensive force platforms may serve as useful adjuncts to athlete performance measurement such as the gymnastics still rings cross.
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The Reliability of Accelerometry to Measure Weightlifting PerformanceSato, Kimitake, Sands, William A., Stone, Michael H. 01 November 2012 (has links)
The purposes of the study were to track weightlifters' barbell acceleration with a portable accelerometer over three training sessions to examine test–retest reliability and to compare peak barbell acceleration at different training intensities. Twelve nationally ranked weightlifters volunteered for this study. The portable accelerometer was attached to the right side of the barbell to measure barbell resultant acceleration during the snatch lift at a sampling frequency of 100 Hz. The data were collected over three training sessions at intensity levels of 80%, 85%, and 90% of one repetition maximum. The data were analyzed using intra-class correlation coefficients (ICCs) for the three training sessions and one-way repeated measure ANOVA to compare the difference in peak barbell acceleration at three intensities. Results showed that the device was highly reliable with an ICC of 0.88 and 95% confidence interval of 0.81–0.93. There were significant differences in peak barbell acceleration at various lifting intensities, indicating a decline of the acceleration as the mass of the barbell became heavier. The portable accelerometer seems useful in measuring barbell acceleration data, which can be analyzed in future studies to monitor a weightlifter's performance in a practical setting instead of testing at a laboratory.
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Sports Content Viewership Motivations Across Digital DevicesHenry, Mark 01 January 2016 (has links)
U.S. advertisers spent over $2 billion on sporting events in 2014 directing advertisements towards consumers through digital devices used such as televisions, computers, smartphones, and tablets. The purpose of this cross-sectional study was to identify motivation factors that predict the intention to view sports content on digital devices. Knowing such factors is important for advertisers to prioritize distribution channels. Uses and gratification theory formed the theoretical framework for the study. The methodology adapted a survey that encapsulated 9 motives. The research questions examined what motives influenced sports viewership, what motives predicted the intention to view specific sports content, and the differences in viewing intention across sports content types. Data were collected through a survey administered to a qualified random sample of U.S. respondents with 525 responses received. Data were analyzed using exploratory factor analysis to group the questions into motivation factors, multiple linear regression to determine the significance of these factors in predicting viewership intent, and nonparametric Friedman testing to determine what demographics influenced viewership. Findings included: (a) 8 factors explained 76% of the variance; (b) 8 motives were significant in predicting viewership intention, with Escape (β = .714) ranking the highest; and (c) younger viewers had a greater intent to consume content on digital devices other than television, with smartphones (M = .73) ranking the highest. Social change benefits include: (a) sports content providers and advertisers could target the right content and advertisement to maximize viewership retention and revenue, and (b) users could view their desired sports content on their chosen device.
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Development of the portable satellite laser ranging systemBroomhall, Mark Anthony January 2003 (has links)
The Portable Satellite Laser Ranger (PSLR) is a light weight, highly portable satellite laser ranging system which employs many of the techniques and equipment types of larger fixed systems. It has a primary telescope aperture of 62 cm and uses a 150 ps pulse of 130 mJ at the second harmonic wavelength of 532 nm. The system is designed to use as little ancillary equipment as possible and only requires one small instrument rack and one PC based control computer. All of the control features of the system are based or installed in the control computer.The PSLR project at Curtin University was concerned with repairing and u p grading the PSLR to return the system to operational capacity. This involved the replacement of missing control components, repair of some hardware, modifications to the control program, and several calibration and operational tests. These tests showed that the PSLR system was capable of a ranging accuracy to fixed targets of 8.5 mm with an average accuracy of 23 mm. They showed that the PSLR was capable, in selective conditions, to track star ephemerides to less than 54. The mount error (standard deviation) over several orientations was shown to be 0.253° in elevation and 0.337° in azimuth.This dissertation will discuss; i) the operation of the equipment used with the PSLR and similar systems, the steps taken to repair or replace the necessary equipment, ii) the tests required to calibrate or evaluate various sub-systems of the PSLR and, iii) the results and conclusions drawn as a result.
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Design of an integrated voltage regulator / Design av en integrerad spänningsregulatorKomark, Stina January 2003 (has links)
<p>Many analog systems need a stable power supply voltage that does not vary with temperature and time in order to operate properly. In a battery operated system the battery voltage is not stable, e.g. it decreases with decreasing temperature and with ageing. In that case a voltage regulator must be used, that regulates the battery voltage and generates a stable supply voltage to power other circuitry. </p><p>In this thesis a voltage regulator to be used in a battery operated system has been designed which meets the given specification of stability and power capabilities. A voltage reference, which is a commonly used devise in analog circuits, was also designed. The role of a reference voltage in an electrical system is the same as for a tuning fork in a musical ensemble; to set a standard to which other voltages are compared. </p><p>A functionality to detect when the lifetime of the battery is about to run out was also developed.</p>
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Portable capillary electrophoresis system with LED-absorbance photometric and LED-induced fluorescence detection : Design, characterisation and testingStjernlöf, Anna January 2008 (has links)
<p>Capillary electrophoresis (CE) has a wide range of applications in the field of analytical chemistry. In general the most expensive part in a CE system is the detector due to the fact that the detector must have a high sensitivity for small detection volumes and low concentrations. Building portable instruments is one way to make the instruments cheaper and has the advantage that they can be used virtually everywhere. However, downscaling of CE instruments puts some extra demands on the detector. This report describes the design and building of two homemade light-emitting diode (LED) based detectors; a LEDabsorbance photometric detector (LED-AP) and a LED-induced fluorescence (LED-IF) detector. The main goal was to install them inside a portable CE and make a simple separation. The performance of the two detectors had to be evaluated before the main goal could be achieved. p-Nitrophenol was used to create a sensitivity graph for the LED-AP detector, calculating the upper linearity to 5.6 mM when the sensitivity had dropped 10 % caused by non-linearity. The sensitivity graph also showed that the detector had an effective pathlength of 74.2 µm and a stray light of 4.5 % for a 75 µm i.d fused-silica capillary. The LED-IF detector was evaluated by determining the limit of detection (LOD) for fluorescein, at a signal to noise ratio of 3. The LOD was 0.72 µM ± 0.01 µM when immersion oil was used to limit the light scattering from the optic fibres in to the capillary and 0.58 µM ±0.02 µM when silicone oil was used. Without doing any improvements only the LED-AP detector could be used in the portable CE. As a common application area for portable CE instruments is environmental analysis, indirect detection using p-nitrophenol as a probe for separating anions was done to test the system. All analytes were eluted in less than 4 minutes.</p>
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