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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.

Selected topics in video coding and computer vision

Dai, Congxia. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains xi, 100 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 91-100).

Realistic texture in simulated thermal infrared imagery /

Ward, Jason T. January 2008 (has links)
Thesis (Ph.D.)--Rochester Institute of Technology, 2008. / Typescript. Includes bibliographical references (p. 155-160).

Thermal evaluation of an integrated circuit chip using infrared imaging and finite element techniques /

Lerch, Terence. January 1991 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1991. / Typescript. Includes bibliographical references.

Temperature, pressure, and infrared image survey of an axisymmetric heated exhaust plume /

Nelson, Edward L. January 1994 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 170-176). Also available via the Internet.

Validation of DIRSIG, an infrared synthetic scene generation model /

Rankin, Donna D. January 1993 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1993. / "February 1992." Typescript. Includes bibliographical references (leaves 94-95).

Radiometric modeling of mechanical draft cooling towers to assist in the extraction of their absolute temperature from remote thermal imagery /

Montanaro, Matthew. January 2009 (has links)
Thesis (Ph.D.)--Rochester Institute of Technology, 2009. / Typescript. Includes bibliographical references (p. 171-175).

Heat transfer in DIRSIG : an infrared synthetic scene generation model /

Sirianni, Joseph D. January 1994 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1994. / Typescript. Includes bibliographical references (leaves 52-53).

Infrared thermography (IRT) for the assessment of microvascular skin blood flow in a specialist connective tissue disease unit

Howell, Kevin J. January 2009 (has links)
Aim. To establish standardised infrared thermography (IRT) within a specialist connective tissue disease unit, assessing its utility: • for the evaluation of Raynaud’s Phenomenon (RP) in clinical rheumatology and research • for the detection of active localised scleroderma (LS) lesions in paediatric patients and to develop improvements in IRT quality assurance for these medical applications. Methods. For the evaluation of RP, a protocol for cold challenge of the feet was developed and validated. IRT was applied with hand cold challenge for the assessment of response to oral vasodilator therapies in two large randomised pilot studies. An infrared thermometer technique was developed, validated against IRT, and subsequently used for the assessment of peripheral vasospasm in a twin study into the heritability of RP. The utility of inspection of thermograms for detecting clinically active LS lesions was established. A protocol was developed incorporating photography, IRT and laser Doppler flowmetry (LDF) for LS assessment, and the normal range of temperature and LD blood flow across several body sites was established in adults and children. The utility of the protocol for assessing LS activity in children was investigated. To develop quality assurance of thermography, the author contributed to the specification and validation of blackbody medical temperature reference sources, and published guidelines for procuring and commissioning a medical thermal imager. Results. Healthy controls had a higher mean toe temperature than RP patients (at baseline 29.2 ± 1.5oC v 24.8 ± 1.5oC [mean ± SD], p < 0.01; t-test). IRT demonstrated improved finger rewarming 10 minutes after cold challenge in primary RP patients 11 treated with fluoxetine compared with those treated with nifedipine (58.8% v 43.1%, p=0.03; t-test). IRT showed no such improvement in finger rewarming over nifedipine in patients treated with losartan. In a hospital setting, an infrared thermometer technique performed similarly to IRT with cold challenge for the detection of RP: the sensitivity of IRT was 83%, whereas for the infrared thermometer it was 89%. The specificity of both instruments was 84%. In a population setting using the infrared thermometer both baseline finger temperature and rewarming after ten minutes were significantly lower for RP subjects than for controls (for baseline: 28.3oC v 30.0oC, p < 0.01, t-test; for rewarming: 4.6oC v 5.3oC, p < 0.05, t-test). Infrared thermometer measurements in monozygotic and dizygotic twin pairs revealed a heritability of 65% for baseline finger temperature, 35% for fall after cold challenge, and 24% for rewarming over ten minutes. In the larger of two published studies on the inspection of thermograms for detecting clinically active LS, sensitivity was 92%, and specificity was 68%. In lesions imaged within 2 years of onset, sensitivity was 81% and specificity 88%. Validation of a protocol combining IRT and LDF measurements revealed that, in adult controls, the mean temperature difference between the two sides of the body was less than 0.5oC at all body regions. Mean differences in contralateral LD flux were less than 40% at all body sites. Variability in LD and IRT readings due to experimental factors was acceptably small in comparison to the physiological differences recorded. Applying the protocol in children with LS, the median relative increase in LD blood flow in clinically active lesions (compared with blood flow in contralateral unaffected skin) was 89% (range -69% to +449%), whereas the median flow increase in clinically inactive lesions was 11% (range -46% to +302%), p < 0.001. Using IRT, the median temperature difference between clinically active lesions and contralateral unaffected skin was 0.5°C (range -0.1°C to +4.1°C), whereas the median temperature difference for clinically inactive plaques was 0.3oC (range -1.9°C to +2.7°C), p=0.024. 12 In hand cold challenge measurements made at the Royal Free Hospital, application of the medical blackbody temperature reference sources reduced the overall uncertainty in temperature readings by a factor of about 4, from typically ±2°C to ±0.5°C. Conclusion. IRT or infrared thermometer data on skin temperature before and after cold challenge affords RP studies an important element of objectivity. RP detected in a population setting exhibits milder vasospasm than RP recruited from hospital patients, and thus the results of research performed at specialist centres may not be translatable to community settings. Inspection of thermograms is an effective method for the detection of clinically active LS, although LDF performed better than IRT using a protocol reliant on objective measurements from small regions of interest. IRT and infrared thermometry were generally less effective at discriminating between healthy and diseased subjects in situations where the temperature difference between groups was small (<2°C). The introduction of temperature reference sources, which reduce uncertainty in radiometric measurements to the order of 0.5°C, would increase the utility of IRT in settings where the temperature change associated with disease is small.

Method of physical and enzymatic concentration of extraneous materials in wheat flour to enable near infrared chemical imaging

Nickoley, Tyler R. January 1900 (has links)
Master of Science / Food Science Institute / David L. Wetzel / Grain processing and handling requires quality determinations to ensure wholesome products that meet or surpass legal standards and specifications required by the end consumer. Near infrared spectroscopy has proven to be a useful and versatile tool to enable grain processers to make adjustments as needed. Near infrared chemical imaging also provides spatial information within the image and relative composition of chemically distinct components within the product. The potential use of chemical imaging to determine extraneous material in bread baking quality flour was addressed. A specimen preparation technique was developed. Insect fragment spiked specimens were imaged to determine their imaging effectiveness for application near the allowable limit of insect fragment concentration. Imaging was achieved using indium antimonide array detection of diffusely reflected radiation. The detector array of 81,920 pixels collected radiation from an area of 30.72 mm by 38.4 mm with a pixel size of 120 µm². Spectra were collected simultaneously from each pixel without moving parts by scanning with a liquid crystal tunable filter. Partial least squares analysis of each pixel within the sample allowed a summation of the insect quantity. The chemical structural distinction of chitin in the high protein matrix of the insect residue was in contrast to the non-digested carbohydrate residue in the lesser protein matrix of the flour. The method developed provided a linear response for a concentration range from approximately half the allowable limit to twice the limit for two insects that commonly contaminate flour. For the two insects studied the slopes are comparable with a slight off-set over a practical working range, so that insect concentration can be determined independently of species recognition.

Active and Passive Thermography for the Detection of Defects in Green-State Powdermetallic Compacts

Benzerrouk, Souheil 20 September 2011 (has links)
"Despite its maturity, the powder metallurgy (PM) fabrication process continues to rely heavily on indirect methods to determine and predict the quality of its compacts early in the manufacturing line. Currently, the most comprehensive testing is performed on sintered parts, resulting in higher cost and increased waste. This dissertation addresses the need of early inspection by developing a novel approach whereby PM compacts are tested in the green-state without intrusion and with minimal cost per compact tested. The method is based on an infrared detection scheme with two fundamental embodiments. For high resolution applications, or offline testing, an active thermography approach is adopted; electric energy is deposited into the compact in a contact-less fashion to evaluate all parts for cracks, inclusions, or delaminations. As an alternative, for lower resolution high-yield applications, a system based on a passive thermography approach is developed. This system relies on residual heating emanating from the process. Thermal data is then collected and analyzed in an effort to yield part integrity and process stability information. In this dissertation we will discuss our design approach, theoretical modeling aspects, and a proof-of-concept instrument with associated data processing software. We will first describe the underlying physical principles, followed by predictions from the modeling formulation, including a solution of the heat equation. As part of our experimental data processing, we will present results that are collected both in a laboratory setting and in an industrial manufacturing line. The integrity of the compacts is carried out with the aid of a specialized software package."

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