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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.
71

Optical Design Of A Thermal Infrared Imager For A Micro-satelite

Salcin, Esen 01 July 2006 (has links) (PDF)
Space-based infrared Earth observation systems provide a unique opportunity for the detection of thermal variations on Earth&amp / #8217 / s surface or atmosphere. The objective of this study is to propose an optical design of a thermal imager that is suitable for flight on a micro-satellite platform at an altitude of 650 km, providing the necessary resolution requirements under the considerations of physical boundaries of the given platform. Before the optical design, the parameters which would strictly bound the optical system such as the infrared source, atmospheric transmission, the detector and optical materials for infrared as well as the working conditions for the microsatellite were examined. Simulations and further optimization efforts resulted with a high performance optical system design.
72

Medical Electro-thermal Imaging

Carlak, Hamza Feza 01 February 2012 (has links) (PDF)
Breast cancer is the most crucial cancer type among all other cancer types. There are many imaging techniques used to screen breast carcinoma. These are mammography, ultrasound, computed tomography, magnetic resonance imaging, infrared imaging, positron emission tomography and electrical impedance tomography. However, there is no gold standard in breast carcinoma diagnosis. The object of this study is to create a hybrid system that uses thermal and electrical imaging methods together for breast cancer diagnosis. Body tissues have different electrical conductivity values depending on their state of health and types. Consequently, one can get information about the anatomy of the human body and tissue&rsquo / s health by imaging tissue conductivity distribution. Due to metabolic heat generation values and thermal characteristics that differ from tissue to tissue, thermal imaging has started to play an important role in medical diagnosis. To increase the temperature contrast in thermal images, the characteristics of the two imaging modalities can be combined. This is achieved by implementing thermal imaging applying electrical currents from the body surface within safety limits (i.e., thermal imaging in active mode). Electrical conductivity of tissues changes with frequency, so it is possible to obtain more than one thermal image for the same body. Combining these images, more detailed information about the tumor tissue can be acquired. This may increase the accuracy in diagnosis while tumor can be detected at deeper locations. Feasibility of the proposed technique is investigated with analytical and numerical simulations and experimental studies. 2-D and 3-D numerical models of the female breast are developed and feasibility work is implemented in the frequency range of 10 kHz and 800 MHz. Temporal and spatial temperature distributions are obtained at desired depths. Thermal body-phantoms are developed to simulate the healthy breast and tumor tissues in experimental studies. Thermograms of these phantoms are obtained using two different infrared cameras (microbolometer uncooled and cooled Quantum Well Infrared Photodetectors). Single and dual tumor tissues are determined using the ratio of uniform (healthy) and inhomogeneous (tumor) images. Single tumor (1 cm away from boundary) causes 55 &deg / mC temperature increase and dual tumor (2 cm away from boundary) leads to 50 &deg / mC temperature contrast. With multi-frequency current application (in the range of 10 kHz-800 MHz), the temperature contrast generated by 3.4 mm3 tumor at 9 mm depth can be detected with the state-of-the-art thermal imagers.
73

Use of digital infrared thermal imaging (DITI) for early detection of mastitis and to assess mammary function and lameness in dairy cattle

Schmidt, Stephanie Jean. January 2008 (has links)
Thesis (M.S.)--Mississippi State University. Department of Animal and Dairy Sciences. / Title from title screen. Includes bibliographical references.
74

Seedlet Technology for anomaly detection

Patton, Michael Dean. January 2002 (has links)
Thesis (Ph. D.)--Mississippi State University. Department of Electrical and Computer Engineering. / Includes bibliographical references.
75

Rainfall estimation from satellite infrared imagery using artificial neural networks

Hsu, Kuo-lin,1961- January 1996 (has links)
Infrared (IR) imagery collected by geostationary satellites provides useful information about the dirunal evolution of cloud systems. These JR images can be analyzed to indicate the location of clouds as well as the pattern of cloud top temperatures (Tbs). During the past several decades, a number of different approaches for estimation of rainfall rate (RR) from Tb have been explored and concluded that the Tb-RR relationship is (1) highly nonlinear, and (2) seasonally and regionally dependent. Therefore, to properly model the relationship, the model must be able to: (1) detect and identify a non-linear mapping of the Tb-RR relationship; (2) Incorporate information about various cloud properties extracted from IR image; (3) Use feedback obtained from RR observations to adaptively adjust to seasonal and regional variations; and (4) Effectively and efficiently process large amounts of satellite image data in real-time. In this study, a kind of artificial neural network (ANN), called Modified Counter Propagation Network (MCPN), that incorporates these features, has been developed. The model was calibrated using the data around the Japanese Islands provided by the Global Precipitation Climatology Project (GPCP) First Algorithm Intercompari son Project (AIP-I). Validation results over the Japanese Islands and Florida peninsula show that by providing limited ground-truth observation, the MCPN model is effective in monthly and hourly rainfall estimation. Comparison of results from MCPN model and GOES Precipitation Index (GPI) approach is also provided in the study.
76

Design and fabrication of a continuous flow mixer for investigating protein folding kinetics using focal plane array Fourier transform infrared spectroscopy

Haq, Moeed. January 2008 (has links)
This thesis presents the design, fabrication, and testing of a micromixing device intended for use in investigating protein dynamics on a microsecond timescale by Fourier transform infrared (FTIR) spectroscopy. Numerical modeling of flow was implemented to predict the influence of flow rates and geometric variations on mixing performance in three passive mixers. The simulation models were validated by experimental measurements using optical and infrared detection. The optimum level of mixing was observed in a multi-lamination mixer that combined thin filaments of differing fluids in an alternating manner. The multi-laminates were transferred onto polished calcium fluoride infrared-transparent optical windows by lithographic processing of an Epon-based polymer, SU-8. A rigid seal between two microchannels was accomplished through thermal bonding of an unexposed resist layer, which acted as a thermal epoxy under the influence of temperature. The multi-lamination mixer was used to study the changes in the secondary structure of beta-Lactoglobulin in deuterated phosphate buffer under varying physicochemical conditions by time-resolved FTIR spectroscopy using focal plane array detection. Upon a pH jump from pH 2 to neutral pH, a gradual loss of alpha-helical content, accompanied by an increase in random coils and turns was observed within 2 ms of mixing. In a second kinetic experiment, mixing of a neutral-pH solution of beta-Lactoglobulin with a 60% trifluoroethanol solution resulted in the formation of an alpha-helical intermediate with an accompanying increase in intramolecular beta-sheet structure within 500 mus of mixing. These results indicate that the multi-lamination mixer designed and fabricated in this study is well suited for investigations of protein dynamics on the micro- to millisecond timescale by time-resolved FTIR spectroscopy.
77

Techniques for evaluation of visual performance in terrain assessment and three-dimensional material manipulation operations

McWhorter, Shane William 12 1900 (has links)
No description available.
78

Focal plane array-Fourier transform-infrared (FPA-FTIR) spectroscopy as a tool in the simple and rapid classification of common environmental and food spoilage fungi

Pinchuk, Orley R. (Orley Rachel), 1980- January 2008 (has links)
Environmental and food spoilage fungi cause billions of dollars in damage in North America alone each year, in the form of rotted wood and crops, spoiled food, and human and animal illness. Each of these threats could be drastically reduced if early and more rapid detection processes are developed to replace the serological methods that are currently in practice. The current North American protocol for establishing identification of contaminating fungi both in environment and food have a time frame of approximately one week to twenty-two days. The use of a Fourier transform infrared (FTIR) spectrometer, coupled with a focal-plan-array (FPA) detector, can theoretically shorten the time (analysis within minutes after obtaining a pure culture) it takes to identify and classify a fungal cell. FPA-FTIR spectroscopy is advantageous as little to no sample preparation is required and results are obtained in less than one minute per sample. The fungal subset chosen for this study includes representatives from five phyla, including Zygomycota (Mucor heimalis), Ascomycota (Neurospora crassa, Ophiostoma minor, Chaetomium globosporum, Alternaria brassicicola), Basidiomycota (Schizophyllum commune, Chaetomium globosporum), Deutromycota (Aspergillus niger, Penicillium notatum, Aureobasidium pullulans) and the Mycetozoa (dictyostelium discoideum, physarum polycephalum). Different variables were tested and evaluated, including variability in growth parameters, wet deposition of fungi versus dry smearing of fungi, optimal absorbance range, and spectral processing parameters as well as discrepancies from one instrument to another, as well as spectral reproducibility from one instrument to another. By following the experimental protocol developed, reproducible spectra were attained, and differentiation of the fungi within the set selected for this study was achieved. The results of this work demonstrate that FPA-FTIR spectroscopy can potentially be employed for the accurate identification of environmental and food spoilage fungi.
79

Real Time Image Processing For Medical Infrared Imaging

Kiziloz, Cemil 01 December 2005 (has links) (PDF)
This thesis focuses on Medical Infrared Imaging. It deals with the implementation of an infrared imaging system that can be used as a thermograph. A user interface program is also signed in order to control the imaging system. The system is implemented using Very High Speed Integrated Circuit Description Language (VHDL). Digitizing the data is implemented by Field Programmable Gate Array. Non-uniformities at the detector data are corrected by the two-point correction algorithm. To obtain absolute temperature readings, another system calibration process is also performed. Real-time histogram equalization algorithm and a realtime convolution operation are implemented using the VHDL. Tests of these implementations are performed by comparing the results with the numerical values. A user interface program is developed to allow the operator select any filter type and measure the temperature of any point in the object. Previous studies showed that an infrared system should detect a temperature difference of 500&deg / mK if it is to be used for biomedical applications. Using a black body system with a precise temperature control, it is shown that this specification is satisfied. Clinical evaluations for a few patients reveal that the implemented medical infrared system can be used for biomedical applications.
80

Quantitative analysis of infrared images for early breast cancer detection /

Koay, Jessica Phaik Sun, January 1900 (has links)
Thesis (M. App. Sc.)--Carleton University, 2005. / Includes bibliographical references (p. 102-116). Also available in electronic format on the Internet.

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