• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 14
  • 7
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 34
  • 34
  • 7
  • 6
  • 5
  • 5
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 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

Real-time measurement of on-road fine particulate matter in Atlanta

Papier, Mark Elliot 01 April 2008 (has links)
Particulate matter is increasingly linked to health effects not only for what was previously thought to be just a respiratory problem, but also for the cardiovascular system. Literature not only supports that high particulate matter over long periods of time is correlated to morbidity and mortality due to both cardiovascular and respiratory means, but that high levels of particulate matter, even in short bursts of high concentrations, may be the triggering mechanism for the onset of such problems. Due to automobiles being a prime source of particulate matter, roadway concentrations are often higher than those measured at off-road measurement sites run by various parts of the United States Government. Furthermore, the government run sites are averaged over timescales at a minimum of an hour and at a maximum of a running three-day twenty-four hour length. These are both so long that mesoscale information about the particulate matter, such as short duration high intensity bursts, would be completely removed from the dataset. This study utilizes a real-time portable instrumentation package, which can effectively measure particulate matter concentrations on the roadways of metro Atlanta. Measurements are taken both inside the cabin of a vehicle, which does have an in-cabin filtration system, and on a bicycle ridden along the streets without any form of filtration. These instruments, specifically calibrated handheld particle counters, did indeed find some spikes of particulates above the government s one-hour averages inside the cabin of a vehicle. Arguably more importantly, while riding a bicycle these handheld particle counters also found spikes of particulates approaching six times the amount monitored by the government sites, and several roadway averages that were higher than the off-road averages for the same time.
32

Development and Testing of a Second Generation Hand-held Optical Imager

Gonzalez, Jean 22 March 2012 (has links)
Hand-held optical imagers are developed towards clinical breast cancer imaging. Herein, a Gen-2 hand-held optical imager has been developed with unique features: (i) image curved breast tissues with ~86% surface contact, and (ii) perform reflectance and transillumination imaging using the novel forked probe heads. Extensive phantom studies were performed using 1% Liposyn solution (background, ~ 300 ml and 1000 ml volumes) and 0.45 cc India Ink (absorption) targets, under different target:background contrast ratios and target depths. Two-dimensional surface images detected target(s) up to 2.5 cm deep via reflectance imaging, and up to 5 cm deep via transillumination imaging. Preliminary studies on gel-based breast phantoms (~700 ml) detected targets via reflectance and transillumination imaging. Preliminary in-vivo reflectance studies on normal and cancerous breast tissues also detected targets, although with artifacts. In future, the portable Gen-2 imager has potential for clinical breast imaging via reflectance and transillumination approach after extensive in-vivo studies.
33

Using multi-modal bio-digital technologies to support the assessment of cognitive abilities of children with physical and neurological impairments

Gan, Hock Chye January 2015 (has links)
Current studies done using a learning test for children have problems as they only make evaluations of Physically and Neurologically Impaired (PNI) children who can succeed in the test and can be considered as a PASS/FAIL test. This pilot study takes a holistic view of cognitive testing of PNI children using a user-test-device triad model and provides a framework using non-PNI children and adults as controls. Comparisons using adapted off-the-shelf novel interfaces to the computer, in particular, an Electroencephalograph (EEG) head-set, an eye-tracker and a head-tracker and a common mouse were carried out. In addition, two novel multi-modal technologies were developed based on the use of brain-waves and eye-tracking as well as head-tracking technologies to support the study. The devices were used on three tests with increasing cognitive complexity. A self-developed measure based on success streaks (consecutive outcomes) was introduced to improve evaluations of PNI children. A theoretical model regarding a fit of ability to devices was initially setup and finally modified to fit the view of the empirical model that emerged from the outcomes of the study. Results suggest that while multi-modal technologies can address weaknesses of the individual component modes, a compromise is made between the user’s ability for multi-tasking between the modes and the benefits of a multi-modal device but the sample size is very small. Results also show children failing a test with a mouse but passing it subsequently when direct communication is used suggesting that a device can affect a test for children who are of a developing age. This study provides a framework for a more meaningful conversation between educational psychologists as well as other professionals and PNI parents because it provides more discrimination of outcomes in cognitive tests for PNI children. The framework provides a vehicle that addresses scientifically the concerns of parents and schools.
34

Univerzální testovací zařízení pro ověření komunikačních parametrů technologie Narrowband IoT / Universal Tester of Radio Conditions for Narrowband IoT Communication Technology

Možný, Radek January 2019 (has links)
Technology Narrowband IoT is a representative LPWA (Low Power Wide Area) tech-nology that due to its promising features aims for demands of the Internet of Thingsapplications for autonomous data sending from sensors in areas of poor mobile coverage.For such applications, it is beneficial to firstly map properties of communication technol-ogy in areas of intended use and evaluate whether or not is this technology applicable.This Master thesis deals with the design of the hand-held measuring device for evaluationof Narrowband IoT properties. The output of this thesis is firstly comparison of LPWAtechnologies secondly, design of the mentioned device and verification of its functional-ity. And in last part description of measurement of transmission delay for delay-tolerantapplications. Transmission delay is a critical parameter for delay-tolerant applications.Such an application can be, for example, smart electrometers for which there is definedmaximal allowed transmission delay of 10 seconds and therefore it is desirable to evalu-ate whether or not is the deployment of the communication technology Narrowband IoTsuitable in the intended area for delay-tolerant or even for delay-intolerant applications.

Page generated in 0.0521 seconds