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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.
551

An Analysis Of Accreditation Processes, Quality Control Criteria, Historical Events, And Student Performance

Burris, Robert 01 January 2008 (has links)
The purpose of this study was to determine to what extent student performance has been influenced by historical events, legislative mandates, and accreditation processes. This study consists of comparing the Southern Association of Colleges and Schools accreditation processes with those of the Association of Christian Schools International. In completing this qualitative study, the following procedures were implemented: Related research was used to provide a background of the role that historical events, legislation, and accreditation processes have on student performance; data were collected to establish time line shifts in an historical perspective. The data collected included assessment, accountability, high school drop out rates, high school graduation rates, academic readiness for higher education, standardized testing, grade inflation, acceleration of dual enrollment and advanced placement courses, and national SAT and ACT averages. Data were also collected from historical record of accreditation processes, which included standards, teacher certification requirements, committee responsibilities, visiting team responsibilities, and self-study materials. As a result of content analysis, the researcher decided to focus on three key areas that were integral to the study. The three categories identified in the review of literature were used to analyze the content of these events and processes. The categories were: (a) Student Performance, (b) Historical Events, and (c) SACS and ACSI Accreditation Processes. The following results were obtained from this research. Findings indicated that a criterion-based accreditation process potentially results in more consistent student performance outcomes than an open-ended process.
552

Control charts based on residuals for monitoring processes with correlated observations

Lu, Chao-Wen 10 November 2005 (has links)
In statistical process control, it is usually assumed that observations on the process output at different times are lID. However, for many processes the observations are correlated and control charts for monitoring these processes have recently received much attention. For monitoring the process level, this study evaluates the properties of control charts, such as the EWMA chart and the CUSUM chart, based on the residuals from the forecast values of an ARMA model. It is assumed that the process mean is a ftrst order autoregressive (AR(l)) model and the observations are the mean plus a random error. Properties of these charts are evaluated using a Markov chain approach or an integral equation approach. The performance of control charts based on the residuals is compared to the performance of control charts based on the original observations. A combined chart using forecasts and residuals as the control statistics as well as a combined chart using the EWMA of observations and the EWMA of residuals as the control statistics are also studied by simulation. It is found that no universally "good" chart exists among all the charts investigated in this study. In addition, for monitoring the process variance, two kinds of EWMA chart based on residuals are studied and compared. / Ph. D.
553

Defect prediction on production line

Khalfaoui, S., Manouvrier, E., Briot, A., Delaux, D., Butel, S., Ibrahim, Jesutofunmi, Kanyere, Tatenda, Orimogunje, Bola, Abdullatif, Amr A.A., Neagu, Daniel 29 March 2022 (has links)
Yes / Quality control has long been one of the most challenging fields of manufacturing. The development of advanced sensors and the easier collection of high amounts of data designate the machine learning techniques as a timely natural step forward to leverage quality decision support and manufacturing challenges. This paper introduces an original dataset provided by the automotive supplier company VALEO, coming from a production line, and hosted by the École Normale Supérieure (ENS) Data Challenge to predict defects using non-anonymised features, without access to final test results, to validate the part status (defective or not). We propose in this paper a complete workflow from data exploration to the modelling phase while addressing at each stage challenges and techniques to solve them, as a benchmark reference. The proposed workflow is validated in series of experiments that demonstrate the benefits, challenges and impact of data science adoption in manufacturing.
554

Quantifying Appearance for Opaque Surfaces Using Spectral Bidirectional Reflectivity

Brooks, Christopher Richard 01 June 2019 (has links)
Quantifying the appearance of a surface is an important aspect in quality control. Becauseobjects at room temperature emit negligible amounts of radiation into the visible spectrum, aspectsof their appearance may be quantified using reflected light. Therefore, the appearance of opaquesurfaces may be quantified using measurements of the spectral, bidirectional reflectivity. However,measuring the spectral, bidirectional reflectivity of even one point at every set of incident andreflected directions is a time intensive process that is infeasible for quality control.The objective of this work was to determine whether a limited number of spectral, bidirectionalreflectance measurements may be used to characterize the appearance of an opaque surfaceat room temperatures. The results presented in this thesis demonstrate that measurements of thespectral bidirectional reflectivity in the visible spectrum at four sets of specular reflections - 20°,45°, 60°, and 85° - with a resolution of 5 nm may be used to quantify the appearance of an opaquesurface at room temperature. These measurements are converted into parameters called the bidirectionalreflectance appearance parameters (BRAPs). These BRAPs include L*, a*, b* (whichdefine the color of the surface), G20, G60, G85 (which define the gloss of the surface), and H(which describes the haze of the surface). It is shown that surfaces which appear similar havesimilar BRAPs and surfaces which appear different have different BRAPs.
555

Reliability of Electronics

Wickstrom, Larry E. 12 1900 (has links)
The purpose of this research is not to research new technology but how to improve existing technology and understand how the manufacturing process works. Reliability Engineering fall under the category of Quality Control and uses predictions through statistical measurements and life testing to figure out if a specific manufacturing technique will meet customer satisfaction. The research also answers choice of materials and choice of manufacturing process to provide a device that will not only meet but exceed customer demand. Reliability Engineering is one of the final testing phases of any new product development or redesign.
556

Field application of the PM Device and assessment of early age behaviors of cement stabilized pavement layers

Sullivan, William Griffin 30 April 2021 (has links)
Cement stabilized material used for subbase or base pavement layers has been a widely accepted practice by many state Departments of Transportation (DOTs); particularly, for DOTs with limited access to quality crushed aggregates for pavement construction. Despite over 100 years of use, construction specifications governing cement stabilized pavement layers have largely remained the same and are primarily method based specifications (i.e. individual components evaluated and construction methods prescribed) rather than evaluating or testing mechanical properties of the end product. With the recent emergence of the Plastic Mold compaction Device (PM Device), multiple agencies are looking to depart from method based soil-cement specifications by implementing the PM Device for design and construction quality control and quality assurance (QC/QA) testing. Prior to this dissertation, PM Device protocols have been validated under lab conditions but only limited field validation had been performed. Additionally, time delay between initial mixing and compaction of cement stabilized soils is a known issue, which can affect compaction of PM Device specimens as well as construction target density values determined through AASHTO T134 Proctor testing. The main objectives of this dissertation are to investigate time delay effects on cement stabilized soil compactability during Proctor testing, develop a nationally recognized Standard Practice for PM Device specimen fabrication, and perform PM Device field evaluations for QC/QA testing. Lab experiments were conducted to investigate time delay effects and finalize PM Device Standard Practice protocols. Five field projects were evaluated to validate PM Device QC/QA applications and Standard Practice protocols in a construction environment. Time delay was observed to have a notable detrimental influence on compactability during AASHTO T134 Proctor testing and PM Device specimen fabrication. Recommended guidance was provided to characterize compaction delay effects. AASHTO PP92-19 was developed and published by AASHTO's Committee on Materials and Pavements to standardize specimen fabrication for the 3x6 inch and 4x8 inch versions of the PM Device. The PM Device fared well for construction activities when benchmarked relative to density, strength, and modulus of cores taken from constructed cement stabilized pavement layers. The PM Device was recommended for implementation consideration by state DOTs and other agencies.
557

Multivariate Extensions of CUSUM Procedure

Hongcheng, Li 27 July 2007 (has links)
No description available.
558

Rapid Compositional Assessment of Tomato Fruit by Using Portable Mid-Infrared Spectroscopy.

Landers, Emilee Kathleen January 2014 (has links)
No description available.
559

Characterization of the <i>in vitro</i> and <i>in vivo</i> specificity of <i>trans</i>-editing proteins and interacting aminoacyl-tRNA synthetases

Liu, Ziwei January 2014 (has links)
No description available.
560

AN ABET ASSESSMENT MODEL USING SIX SIGMA METHODOLOGY

LALOVIC, MIRA January 2002 (has links)
No description available.

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