The interaction of quantity and quality performance in a factory is clearly of great economic importance. However, there is very little quantitative analytical literature in this area. This thesis is an essential early research step in analyzing how production system design, quality, and productivity are inter-related in transfer lines. We develop a new Markov process model for machines with both quality and operational failures, and we identify important differences between types of quality failures. We present analytic models, solution techniques, performance evaluations, and validation of twomachine systems as well as longer transfer lines. Through numerical studies, we have investigated some of the conventional wisdom on this interaction, and we have found that the wisdom holds only under specific conditions, and we show that the conventional wisdom is wrong under other conditions. We therefore anticipate that more such research will have a dramatic effect on the performance of factories, and we propose promising research directions.
This paper presents approximation methods for the performance analysis of long manufacturing lines, i.e. lines with more than two machines and one buffer, that have both quality and operational failures. We describe three different versions of long flow lines that differ in the locations of the inspection stations and in the sets of machines that each inspection station monitors. We explain a transformation method that approximates long manufacturing lines that have quality and operational failures with long lines that only have operational failures. Such lines can be evaluated by decomposition methods. We introduce other approximations to quantify the effects of the separation of inspections from operations. Comparison with simulation shows that the solution methods provide reliable performance estimates.
The interaction of quantity and quality performance in a factory is clearly of great economic importance. However, there is very little quantitative analytical literature in this area. This thesis is an essential early research step in analyzing how production system design, quality, and productivity are inter-related in transfer lines. We develop a new Markov process model for machines with both quality and operational failures, and we identify important differences between types of quality failures. We present analytic models, solution techniques, performance evaluations, and validation of twomachine systems as well as longer transfer lines. Through numerical studies, we have investigated some of the conventional wisdom on this interaction, and we have found that the wisdom holds only under specific conditions, and we show that the conventional wisdom is wrong under other conditions. We therefore anticipate that more such research will have a dramatic effect on the performance of factories, and we propose promising research directions.
Autophagy, a main degradation pathway for maintaining cellular homeostasis, and redox homeostasis have recently been considered to play protective roles in neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis. Increased levels of reactive oxygen species (ROS) in neurons can induce mitochondrial damage and protein aggregation, thereby resulting in neurodegeneration. Oxidative stress is one of the major activation signals for the induction of autophagy. Upon activation, autophagy can remove ROS, damaged mitochondria, and aggregated proteins from the cells. Thus, autophagy can be an effective strategy to maintain redox homeostasis in the brain. However, the interaction between redox homeostasis and autophagy is not clearly elucidated. In this review, we discuss recent studies on the relationship between redox homeostasis and autophagy associated with neurodegenerative diseases and propose that autophagy induction through pharmacological intervention or genetic activation might be a promising strategy to treat these disorders.
The eGFR correlates with the VTL, and the eGFR cutoff value can predict a subtherapeutic vancomycin level. eGFR is a reliable and efficient alternative to mGFR for identifying ARC. .
We report a method of broadening the reflection bandwidth of polymer-stabilized cholesteric liquid crystal (PSCLC). The top substrate was consecutively coated with a polyimide (PI) and a reactive mesogen (RM) layer, while the bottom substrate was coated with only PI. We exposed the top substrate with the RM coating to UV light. The reflection bandwidth of the PSCLC samples where the top substrate was over-coated with RM was significantly broader than the samples where both substrates were coated with PI. In addition to the effect of the UV intensity gradient, the RM-coated top substrate has a chemical affinity to bulk RM, promoting formation of the pitch gradient and broadening the reflection bandwidth in the sample.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.