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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.
381

Visual Inspection Of Pharmaceutical Color Tablets

Akturk, Deniz 01 May 2006 (has links) (PDF)
In this work a machine vision system for inspecting pharmaceutical color tablets is presented and implemented. Nonparametric clustering based segmentation is faster and thus more appropriate for real-time applications. Two nonparametric clustering based methods, Nearest Neighbor algorithm and MaxShift algorithm are worked in RGB and HSV color spaces as the segmentation step. The implemented algorithm allows the system to detect the missing and broken tablets, tablet fragments, and the color, size, and shape of individual tablets in pharmaceutical blisters, in real-time. System has two operation modes called &amp / #8216 / &amp / #8216 / training&amp / #8217 / &amp / #8217 / and &amp / #8216 / &amp / #8216 / inspection&amp / #8217 / &amp / #8217 / mode, respectively. Operator selects one point on any tablet in a defect-free training captured image in the &amp / #8216 / &amp / #8216 / training&amp / #8217 / &amp / #8217 / mode. In the correction step an optimization algorithm is required, for which Powell and Downhill Simplex methods are used. Captured image is then corrected for spatial color nonuniformity, segmented, and the position, size, shape, and color of each tablet are extracted in the training mode. The correction and segmentation models / the extracted features generated in the training mode is saved with the user defined values to form the model. Each acquired image in the inspection mode is corrected and segmented according to the blister model and then the blisters are classified as &amp / #8216 / &amp / #8216 / good&amp / #8217 / &amp / #8217 / or &amp / #8216 / &amp / #8216 / bad&amp / #8217 / &amp / #8217 / by comparing the extracted feature values with the user defined tolerances stored in the blister model.
382

車検制度が世帯の自動車取り替え更新行動に及ぼす影響の分析

YAMAMOTO, Toshiyuki, 北村, 隆一, KITAMURA, Ryuichi, 藤井, 宏明, FUJII, Hiroaki, 山本, 俊行 01 1900 (has links)
No description available.
383

Estimation of Spalling Stress in Thermal Barrier Coatings Using Hard Synchrotron X-Rays

SUZUKI, Kenji, TANAKA, Keisuke, AKINIWA, Yoshiaki 07 1900 (has links)
No description available.
384

Effect of specimen geometry on ultrasound diffusion in cement-based aggregates

Sengupta, Anandraj 31 March 2008 (has links)
Following Carslaw [1] and as discussed by Becker et al [2], the diffusion of ultrasonic energy in cement-based aggregates follow the heat diffusion equation. However, due to the finite size of the discs used in experiments by Becker, ultrasound energy is contained within the body for a longer period of time, as compared to [2]. Though the energy content of the disc in reality would eventually decay to zero, due to leaks and other mechanisms, a theoretical study of perfectly adiabatic case is useful to compare the residual energy values to material properties. As a particular example, the input energy sees multiple phenomena inside the material during propagation. The residual energy is this a combined effect of the multiple scattering, dissipative and diffusive processes. This objective of this thesis is to study the relationship between the residual spectral density and specimen geometry. The effort further aims to attribute the difference in the residual spectral energy density values in materials of similar geometry to the varying material properties of the heterogeneous materials. Finally, a study of the error propagation in the estimation is presented, along-with an analytical relationship showing the value of spectral energy density for discs of finite radius and height. Ref: 1. H. S. Carslaw, J.C.J., Conduction of Heat in Solids. 2nd ed ed. 1986: Oxford University Press, USA. 520 2. Becker, J., L.J. Jacobs, and J. Qu, Characterization of cement-based materials using diffuse ultrasound. Journal of Engineering Mechanics, 2003. 129(12): p. 1478-1484.
385

Study of algorithms for analysis of xrf spectra to automate inspection of carpets

Mahuteau, Laurent 25 August 2008 (has links)
The objective of this thesis is to categorize carpet types according to their XRF spectra and verify if further classification of carpets is possible for use of an XRF analysis system in the carpet manufacturing line. This thesis consists of (1) implementing and studying effective algorithms for automated analysis of X-ray spectra, (2) comparing known algorithms for X-ray spectra analysis, and (3) implementing our own algorithm for classification of carpets spectra obtained for further fluorine online analysis of XRF inspected carpets. This research is intended for quick and accurate automated analysis of raw XRF spectra and matching analysis results to a database of XRF spectra of raw carpets. The research uses spectrum signal processing and spectrum analysis regarding efficacy of combined methods for XRF inspected carpets. X-Ray Fluorescence is a key technology for detection of chemical elements. Fluorine is a key element for carpet's quality. XRF has been chosen to be a potential candidate to measure fluorine since it is a versatile tool for low concentration element detection. Due to specific XRF background spectrum for each different carpet type, carpet samples may need specific calibrations for further computation of carpet fluorine concentration. Automating the detection of the carpet type is intended to help in automating the XRF calibration.
386

Development of automated method of optimizing strength of signal received by laser interferometer

Randolph, Tyler W. 12 June 2009 (has links)
The long-term goal of this research is to assist in the development of a fast, accurate, and low-cost nondestructive inspection prototype for solder joints in integrated circuits (IC). The goal of the work described in this thesis is to develop a fully automated system to maintain the signal strength of the vibrometer that would reduce the testing time while maintaining or improving the quality of the defect detection results. The ability to perform the inspections in an automated manner is very important in order to demonstrate the ability of the defect detection system to be used for online inspection without the need of an operator. The system was able to find the maximum signal strength (at a single point on the surface of a flip chip) nearly five times faster than Polytec's commercial system with a search time of approximately 2.1 sec. When integrated into the nondestructive inspection prototype, the system described in this work was found to approximately reduce the data acquisition time per test location by four times, with a minimum data acquisition time of 8.5 sec and an average time of 15.4 sec, while maintaining the same level of quality of results obtained by a skilled operator when manually maintaining the signal strength of the vibrometer. Hardware was developed that retrofitted a vibrometer's focusing head at the end of a fiber optic cable to a motorized linear stage. This stage controlled the standoff distance between the focusing head and the IC's surface with a fixed focal length, which allowed the spot size of the laser to be adjusted while searching for a desired signal strength. Numerous tests were conducted to determine the search parameters, which led to a search time of approximately 2.1 sec. This time was found to be dependent on the surface finish of the IC being inspected. It was also found that to achieve a desired signal intensity strength, not only does the standoff height of the focusing head, which determines the laser spot size, need to be controlled, but also the exact location on which the laser is reflecting off the IC.
387

Three essays in program evaluation: the case of Atlanta inspection and maintenance program

Supnithadnaporn, Anupit 17 June 2009 (has links)
The Atlanta Inspection and Maintenance program ultimately aims to reduce on-road vehicular emission, a major source of air pollution. The program enforces eligible vehicles to be inspected and repaired, if necessary, before the annual registration renewal. However, various factors can influence the program implementation with respect to the motorists, inspectors, and testing technology. This research explores some of these factors by using empirical data from the Continuous Atlanta Fleet Evaluation project, the inspection transaction records, the Atlanta Household Travel Survey, and the U.S. Census Bureau. The study discusses policy implications of findings from the three essays and offers related recommendations. The first essay examines whether the higher income of a vehicle owner decreases the odds of the vehicle failing the first inspection. Findings show that vehicles owned by low-income households are more likely to fail the first inspection of the annual test cycle. However, after controlling for the vehicle characteristics, the odds of failing the first inspection are similar across households. This suggests that the maintenance behaviors are approximately the same for high- and low-income households. The second essay explains the motorists' decisions in selecting their inspection stations using a random utility model. The study finds that motorists are likely to choose the inspection stations that are located near their houses, charge lower fees, and can serve a large number of customers. Motorists are less likely to choose the stations with a relatively high failure ratio especially in an area of low station density. Moreover, motorists do not travel an extra mile to the stations with lower failure ratio. Understanding choices of vehicle owners can shed some light on the performance of inspection stations. The third essay investigates the validity and reliability of the on-board diagnostic generation II (OBD II) test, a new testing technology required for 1966 and newer model year vehicles. The study compares the inspection results with the observed on-road emission using the remote sensing device (RSD) of the same vehicles. This research finds that the agreement between the RSD measurement and the OBD II test is lower for the relatively older or higher use vehicle fleets
388

Immunosensor methods for drug residue control of food : assay design and sample matrix effects /

Johansson, M. Annette, January 2004 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2004. / Härtill 4 uppsatser.
389

'Waiter! There's a fly in my soup - or is that a cockroach?': the moral panic of dirty restaurants in the city of Toronto, Canada /

Leung, Cherie January 1900 (has links)
Thesis (M.A.) - Carleton University, 2005. / Includes bibliographical references (p. 68-74). Also available in electronic format on the Internet.
390

Comparison of screening, evaluation, rehabilitation and design provisions for wood-framed structures /

Baxter, Preston. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2004. / Printout. Includes bibliographical references (leaves 155-158). Also available on the World Wide Web.

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