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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.
171

Integrated circuit outlier identification by multiple parameter correlation

Sabade, Sagar Suresh 30 September 2004 (has links)
Semiconductor manufacturers must ensure that chips conform to their specifications before they are shipped to customers. This is achieved by testing various parameters of a chip to determine whether it is defective or not. Separating defective chips from fault-free ones is relatively straightforward for functional or other Boolean tests that produce a go/no-go type of result. However, making this distinction is extremely challenging for parametric tests. Owing to continuous distributions of parameters, any pass/fail threshold results in yield loss and/or test escapes. The continuous advances in process technology, increased process variations and inaccurate fault models all make this even worse. The pass/fail thresholds for such tests are usually set using prior experience or by a combination of visual inspection and engineering judgment. Many chips have parameters that exceed certain thresholds but pass Boolean tests. Owing to the imperfect nature of tests, to determine whether these chips (called "outliers") are indeed defective is nontrivial. To avoid wasted investment in packaging or further testing it is important to screen defective chips early in a test flow. Moreover, if seemingly strange behavior of outlier chips can be explained with the help of certain process parameters or by correlating additional test data, such chips can be retained in the test flow before they are proved to be fatally flawed. In this research, we investigate several methods to identify true outliers (defective chips, or chips that lead to functional failure) from apparent outliers (seemingly defective, but fault-free chips). The outlier identification methods in this research primarily rely on wafer-level spatial correlation, but also use additional test parameters. These methods are evaluated and validated using industrial test data. The potential of these methods to reduce burn-in is discussed.
172

Correlation between Simulation and Measurement of Microwave Resonator Power Handling

Li, Qian January 2013 (has links)
In modern mobile wireless communication, Base Stations (BS) are the most important equipment to build up the mobile network. One of the key elements in BS is the RF filter, which plays a key role to secure the coverage and reliability of the BS. Especially, at Transmitter (Tx) side, the filter must have a high capability to handle the power sent from Power Amplifier (PA) to antenna in any circumstances to ensure the coverage demand. Otherwise, the breakdown will be encountered, setting the power flow in the BS system in an abnormal manner that, finally can lead to the shut down of BS or destroy the system permanently. In this project, three methods using two simulation tools to predict the power handling capability of the RF/microwave resonator which is the elementary component in the BS’s filter are proposed. Power handling tests of selected configurations corresponding to the simulations are implemented as well. In the next stage, the results from the prediction and measurement are compared. Finally, the conclusions of correlation between the prediction and measurement of microwave resonator power handling will be derived.
173

Three Dimensional Deformation of Orthodontic Brackets

Melenka, Garrett W. Unknown Date
No description available.
174

BROADBAND SEISMIC ANALYSES OF THE CRUST AND NOISE SOURCES IN ALBERTA, C ANADA

Shen, Luyi Unknown Date
No description available.
175

Is uncorrelating the residuals worth it?

Ward, Laurel Lorraine January 1973 (has links)
No description available.
176

Familial aggregation of childhood health and the socioeconomic gradient of disease: a longitudinal population-based sibling analysis

Hiebert, Brett 12 September 2011 (has links)
This study explores the relationships that emerge between socioeconomic status (SES) and the prevalence of several health outcomes in children of different ages utilizing administrative data housed at The Manitoba Centre for Health Policy (MCHP). This research also determines the effect that family has on a child developing (or not developing) a specific health outcome. Finally, the relationship between prevalence and familial aggregation are examined. The Johns Hopkins ACG(r) Case-Mix System grouped various physician and hospital diagnosis codes into 32 Aggregated Diagnostic Groups (ADGs). Eight of these ADGs were assessed at four age groups (0-3, 4-8, 9-13 & 14-18) for each member of the final study population. Each member was assigned to one of six SES groups, five income quintile groups and one social assistance group. Familial aggregation was determined for eight selected ADGs using an intraclass correlation coefficient (ICC). Statistical contrasts were made for SA vs. Q1-Q5 and an overall linear trend (SA – lowest; Q5 – highest) to establish the SES differences for the prevalence and familial aggregation of a particular condition. Many of the conditions across SES had statistically significant (p<0.05) linear and SA vs. Q1-Q5 contrasts for 3 both ICCs and prevalence at all age groups. Of the eight ADGs that familial aggregation was calculated, chronic conditions related to the eye had the highest ICCs at all age groups. Injury ADGs had consistently lower ICCs for all age groups. Factors that affected the results of ICC estimation for binary outcomes include the number of bootstrap selections, the width of the age group and the event rate for the outcome of interest. Suggested future research includes a validity review of ICC estimates for binary outcomes, exploring the variables that may reduce or eliminate the SES gradient for ICCs and exploring the aggregation for different study samples within Manitoba.
177

Automation of Unloading Graincars using “Grain-o-bot”

Lokhamoorthi, Aravind Mohan 16 January 2012 (has links)
Large quantities of bulk grain are moved using graincars in Canada and other parts of the world. Automation has not progressed significantly in the grain industry probably because the market is limited for automated systems. A prototype of a robot (“Grain-o-bot”) using machine vision to automatically open and close graincar hopper gates and detect the contents of the graincar was built and studied. The “Grain-o-bot” was a Cartesian robot equipped with two cameras and an opening tool as the end-effector. One camera acted as the eye to determine the sprocket location, and guided the end-effector to the sprocket opening. For most applications, machine vision solutions based on pattern recognition were developed using images acquired in a laboratory setting. Major constraints with these solutions occurred when implementing them in real world applications. So the first step for this automation was to correctly identify the hopper gate sprocket on the grain car. Algorithms were developed to detect and identify the sprocket under proper lighting conditions with 100% accuracy. The performance of the algorithms was also evaluated for the identification of the sprocket on a grain car exposed to different lighting conditions, which are expected to occur in typical grain unloading facilities. Monochrome images of the sprocket from a model system were acquired using different light. Correlation and pattern recognition techniques using a template image combined with shape detection were used for sprocket identification. The images were pre-processed using image processing techniques, prior to template matching. The template image developed from the light source that was similar to the light source used to acquire ii images was more successful in identifying the sprocket than the template image developed using different light sources. A sample of the graincar content was taken by slightly opening and immediately closing the hopper gates. The sample was identified by taking an image using the second camera and performing feature matching. An accuracy of 99% was achieved in identifying Canada Western Red Spring (CWRS) wheat and 100% for identifying barley and canola.
178

Computerized evaluations of the relative abilities of parametric methods to correlate and extrapolate long-time creep-rupture data

Raut, Pravin Kamalakar 05 1900 (has links)
No description available.
179

A Study of Southern Spectroscopic Binaries

Thompson, Vincent Brent January 2009 (has links)
The study of spectroscopic binaries is by no means a new area of study. The Doppler shifting of spectral lines as the stars orbit around each other is now able to be measured very precisely. Binary stars give a reliable means of determining stellar parameters such as the mass. A star's mass is one of the most dominant factors in determining its evolution. Stars for study in this thesis were selected from SB9 (the ninth catalogue of spectroscopic binaries). They were chosen on criteria such as apparent visual magnitude, orbital period, orbital solution grade, equatorial velocity and position. Only stars with poor to average orbital solutions were chosen as it is these orbits which need the most work done. In total 6 spectroscopic binary systems were chosen for study in this thesis. Four single lined spectroscopic binaries (HD 70958, HD 110318, HD 122223 and HD 141544) and two double line spectroscopic binaries (HD 110317 and HD 148704). Unfortunate observing conditions meant that adequate phase coverage of HD 110317 and HD 110318 was not achieved. Adequate phase coverage of the star HD 122223 was also not achieved but this is likely a result of the period being about three years and not about 207 days as quoted in the catalogue. Observations were carried out with the HERCULES spectrograph and the 1-metre McLellan telescope at the Mt John University Observatory from December 2007 until September 2008. Radial velocities were than measured from these spectra with HRSP3 and then orbital solutions were derived. Orbital solutions have been derived for the single-lined systems HD 141544 and HD 70958. The precision of HD 141544 was much better than HD 70598. This is because HD 70958 is complicated by differential rotation and possible chromospheric activity. The orbital solution of the double lined system HD 148704 was obtained by using CARTopt and not TODCOR as is common, with good results. HD 122223 is included even though only six spectra were obtained as it will be evident that the current orbital solution should be rejected in favour of the previous solution obtained in 1936 by Christie. Although the amount of data was not as large as was hoped, significant improvements of the orbital solutions were obtained. The secondary component of HD 148704 had only previously being detected in a very few spectra but now has a good orbital solution. Errors on all parameters have been decreased and tighter limits have been placed on the secondary components of the single lined systems. The mass ratio of the components of HD 148704 was also determined very accurately and calculation of the inclination from photometry may allow accurate masses to be determined.
180

Familial aggregation of childhood health and the socioeconomic gradient of disease: a longitudinal population-based sibling analysis

Hiebert, Brett 12 September 2011 (has links)
This study explores the relationships that emerge between socioeconomic status (SES) and the prevalence of several health outcomes in children of different ages utilizing administrative data housed at The Manitoba Centre for Health Policy (MCHP). This research also determines the effect that family has on a child developing (or not developing) a specific health outcome. Finally, the relationship between prevalence and familial aggregation are examined. The Johns Hopkins ACG(r) Case-Mix System grouped various physician and hospital diagnosis codes into 32 Aggregated Diagnostic Groups (ADGs). Eight of these ADGs were assessed at four age groups (0-3, 4-8, 9-13 & 14-18) for each member of the final study population. Each member was assigned to one of six SES groups, five income quintile groups and one social assistance group. Familial aggregation was determined for eight selected ADGs using an intraclass correlation coefficient (ICC). Statistical contrasts were made for SA vs. Q1-Q5 and an overall linear trend (SA – lowest; Q5 – highest) to establish the SES differences for the prevalence and familial aggregation of a particular condition. Many of the conditions across SES had statistically significant (p<0.05) linear and SA vs. Q1-Q5 contrasts for 3 both ICCs and prevalence at all age groups. Of the eight ADGs that familial aggregation was calculated, chronic conditions related to the eye had the highest ICCs at all age groups. Injury ADGs had consistently lower ICCs for all age groups. Factors that affected the results of ICC estimation for binary outcomes include the number of bootstrap selections, the width of the age group and the event rate for the outcome of interest. Suggested future research includes a validity review of ICC estimates for binary outcomes, exploring the variables that may reduce or eliminate the SES gradient for ICCs and exploring the aggregation for different study samples within Manitoba.

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