Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Begovic, Miroslav; Committee Member: Hampton, Nigel; Committee Member: Harley, Ronald; Committee Member: Michaels, Thomas; Committee Member: Vidakovic, Brani. Part of the SMARTech Electronic Thesis and Dissertation Collection.

This paper examined the inter-rater reliability of psychological assessments in practical field with 42 inmates’ PCL-R scores. As results, this study showed similar ICC and SEM values to those from PCL-manual. Concerning PCL-R structure, factor 2 showed higher ICC value than factor 1, and facet 4 showed higher ICC value than facet 1, 2, or 3. Especially, facet 2 showed low ICC value. Those are consistent with previous studies. However, ICC yielded by factor 2 only and both factor 1 and 2 showed similar ICC values. Considering theoretical and clinical aspects, it was recommendable to use PCL-R total score as risk assessment, though interpreting facet 2 requires cautions. Concerning to rater’s characteristics, the most influential factor to keep the PCL-R reliability was conducting it on regular basis, rather than licensed status. It was difficult to examine whether or not singed-off contribute to maintain sufficient reliability due to small sample size. In regression model, all rater related variables were not significantly correlated to PCL-R score change between two assessment occasions. PCL-R scores at Time 1 was moderately and negatively correlated to PCL-R score change. This indicated natural regression toward the mean. It is desirable to conduct additional study after obtaining more sample and rater related information, such as clinical experience. Additionally, it requires a consideration to apply findings in this study to female psychopathic subjects. As a policy implication, it is recommendable for personnel division to have psychologists to remain in their psychological work.

M.Phil (Engineering Management) / The importance of an effective maintenance programme cannot be over-emphasized because such a programme plays such an important role in the effectiveness of lean manufacturing. Maintenance may be considered the health care of any engineering equipment and its equipment. It is required to reduce waste effectively, and to run an efficient, continuous locomotive operation within a business or service operation. The cost of regular maintenance is very small when it is compared to the cost of a major breakdown at which time production is held up. The main purpose of regular maintenance is to ensure that all equipment required for production is operating at 100% efficiency at all times. Through short daily inspections, cleaning, lubricating, and making of minor adjustments, minor problems can be detected and corrected before they become major problems that can shut down a production line. A good maintenance programme requires company-wide participation and support by everyone from top executives to shop floor personnel (Dale, 2008) The function of reliability engineering is to develop the reliability requirements for a product, establish an adequate reliability programme, and perform appropriate analyses and tasks to ensure that the product meets its requirements. These tasks are managed by a reliability engineer who usually holds an accredited engineering degree and has additional reliability-specific education and training. Reliability engineering is closely associated with maintainability engineering and logistics engineering. Many problems from other fields can also be tackled using reliability engineering techniques (O’Connor 2010). Reliability is defined as the probability that a device will perform its required function under stated conditions for a specific period of time, and quality can be defined as how the recipient of the product or service views the product (Barringer, 2006). Therefore the two cannot be viewed differently as they both have the same focus which is the end result of the product’s performance. The findings reveal that customers should form part of reliability management systems; the development of ways to identify possible failure before it actually happens is key in achieving reliability targets; and training of key personnel on engineering and quality department as well as resource planning and utilization is a key towards eliminating reliability challenges.

This study describes the reliability reporting practices in empirical studies using eight adolescent alcohol screening tools and characterizes and explores variability in internal consistency estimates across samples. Of 119 observed administrations of these instruments, 40 (34%) reported usable reliability information. The Personal Experience Screening QuestionnaireProblem Severity scale generated average reliability estimates exceeding 0.90 (95% CI=0.90-0.96) and the Adolescent Alcohol Involvement Scale generated average score reliability estimates below 0.80 (95% CI=0.67-0.85). Average reliability estimates of the remaining instruments were distributed between these extremes. Sample characteristics were identified as potentially important predictors of variability in the reliability estimates of all the instruments and all instruments under evaluation generated more reliable scores in clinical settings (M=0.89) as opposed to nonclinical settings (M=0.82; r effect size (38)=0.29, p.10). Clinicians facing instrument selection decisions can use these data to guide their choices and researchers evaluating the performance of these instruments can use these data to inform their future studies.

Meta-analytic methods provide a framework around which an inquiry into MAST and SMAST score reliability was completed. Of the 470 measurement opportunities observed between 1971 and 2005, 62 (13.2%) were coupled with accurate reliability information. Weighted reliability estimates centered on.80 suggesting that the MAST and SMAST generally produce scores of similar and adequate reliability for most research purposes. However, the variability of internal consistency estimates shows that at times these tools will not produce reliable scores, particularly among female and nonclinical respondents. Multiple regression equations provide practical guidelines to improve reliability estimates for the future use of these instruments.

The reliability analysis and reliability-based optimization of laminated circular cylinders under axial buckling instability are studied. Structural reliability is measured in terms of Hasofer-Lind reliability index. The response surface models are used in both the calculation of the reliability index and the reliability-based optimization. In reliability analysis, both deterministic and probabilistic sensitivity factors are investigated; the results show that the reliability index is most sensitive to the applied load and Young's modulus of the material. Two cases are considered in the optimization study. In the first case, the cylinder weight is minimized subject to a reliability constraint whereas in the second case, cylinder reliability is maximized subject to a weight constraint. In addition, two different optimization techniques are studied. In the first technique, a global response surface model of the buckling response based on 3000 Monte Carlo simulations is used for the design optimization whereas in the second technique, multiple local regression models, with each based on approximately 20 simulations, are used in sequential search of an optimum design. An optimum design is found. The results based on sequential application of multiple local regression models are close to those from global optimization while the former is much more efficient in terms of computational cost.

No description available.

The steady downscaling of CMOS technology has led to the development of devices with nanometer dimensions. Contemporaneously, maturity in technologies such as chemical self-assembly and DNA scaffolding has influenced the rapid development of non-CMOS nanodevices including vertical carbon nanotube (CNT) transistors and molecular switches. One main problem in manufacturing defect-free nanodevices, both CMOS and non-CMOS, is the inherent variability in nanoscale fabrication processes. Compared to current CMOS devices, nanodevices are also more susceptible to signal noise and thermal perturbations. One approach for developing robust digital systems from such unreliable nanodevices is to introduce defect- and fault-tolerance at the architecture level. Structurally redundant architectures, reconfigurable architectures and architectures that are a hybrid of the previous two have been proposed as potential defect- and fault-tolerant nanoscale architectures. Hence, the design of reliable nanoscale digital systems will require detailed architectural exploration. In this dissertation, we develop probabilistic methodologies and CAD tools to expedite the exploration of defect- and fault-tolerant architectures. These methodologies and tools will provide nanoscale system designers with the capability to carry out trade-off analysis in terms of area, delay, redundancy and reliability. During execution, the next state of a digital system is only dependent on the present state and the digital signals propagate in discrete time. Hence, we have used Markov processes to analyze the reliability of nanoscale digital architectures. Discrete Time Markov Chains (DTMCs) have been used to analyze logic architectures and Markov Decision processes (MDPs) have been used to analyze memory architectures. Since structurally redundant and reconfigurable nanoarchitectures may consist of millions of nanodevices, we have applied state space partitioning techniques and Belief propagation to scale these techniques. We have developed three toolsets based on these Markovian techniques. One of these toolsets has been specifically developed for the architectural exploration of molecular logic systems. The toolset can generate defect maps for isolating defective nanodevices and provide capabilities to organize structurally redundant fault-tolerant architectures with the non-defective devices. Design trade-offs for each of these architectures can be computed in terms of signal delay, area, redundancy and reliability. Another tool called HMAN (Hybrid Memory Analyzer) has been developed for analyzing molecular memory systems. Besides analyzing reliability-redundancy trade-offs using MDPs, HMAN provides a very accurate redundancy-delay trade-off analysis using HSPICE. SETRA (Scalable, Extensible Tool for Reliability Analysis) has been specifically designed for analyzing nanoscale CMOS logic architectures with DTMCs. SETRA also integrates well with current industry-standard CAD tools. It has been shown that multimodal computational models capture the operation of emerging nanoscale devices such as vertical CNT transistors, instead of the bimodal Boolean computational model that has been used to understand the operation of current electronic devices. We have extended an existing multimodal computational model based on Markov Random Fields (MRFs) for analyzing structurally redundant and reconfigurable architectures. Hence, this dissertation develops multiple probabilistic methodologies and tools for performing nanoscale architectural exploration. It also looks at different defect- and fault-tolerant architectures and explores different nanotechnologies. / Ph. D.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

The thesis considers several connected problems in the study of reliability of systems with unreliable components. Initially it reviews the dichotomic case introducing a new characterization which clarifies the importance of the k-out-of-n structures. This characterization is applied to two problems, failure to operate and to idle and stress-strength modelling. Whilst most previous work has concerned itself with coherent structures, being thought of as reasonable systems, the latter section of the chapter considers the case of non-coherent structures. The following chapter moves from the dichotomic models to multilevel models, considering possible . extensions and producing a hierarchy within the possible definitions. Chapter 3 considers the stochastic properties of such systems, again attension is paid to the k-out-of-n structures and non-coherent models. The final two chapters consider component performance. In chapter 4 the system is assumed to be hierarchical,, so that a component is part of a subsystem, and it is assumed the whole subsystem may be replaced. The effect on the component is examined. The final chapter considers optimal age replacement of a component considering 3 possible alternative criteria.