1,370 research outputs found
Designing-in of Quality Through Axiomatic Design
Decisions made during the design
stage of product & process development profoundly affect product
quality and process productivity. To aid in design decision making,
a theoretical framework is advanced: the axiomatic approach
to design. Axiomatic design consists of: 1) domains in the design
world, 2) mapping between these domains, 3) characterization of
a design by a vector in each domain, 4) decomposition of the
characteristic vectors into hierarchies through a process of zigzagging
between the domains, and 5) the design axioms, viz, Independence
& Information Axioms. Statistical process control
(SE) and other methodologies to improve quality are valid only
when they are consistent with the Independence & Information Axioms.
This paper presents several criteria that govern the design
& manufacture of quality products, To be able to control the quality
of products, a design must satisfy the Independence Axiom. Based
on this axiom and some theorems, several design criteria are
derived & discussed. These criteria provide the bounds for the
validity of some of the SPC techniques being used. When there is
more than one acceptable design of a product or process, the Information
Axiom must be used to select the best design(s)
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The Power of Contextual Talking: On Stimulation, Incorporation, and Situational Motivation that Lead to Communicational Chain
A Study of Initialization in Linux and OpenBSD
The code that initializes a system can be notoriously difficult to understand. In secure systems, initialization is critical for establishing a starting state that is secure. This paper explores two architectures used for bringing an operating system to its initial state, once the operating system gains control from the boot loader. Specifically, the
ways in which the OpenBSD and Linux operating systems handle initialization are dissected
The Effects of Consumption Value and Ethical Fashion Consumption Awareness on Ethical Fashion Consumption Behavior
This study addresses the research gap by exploring relationship between consumption value and ethical fashion consumption by its category
Experimental study on pressure distribution and flow coefficient of globe valve
In this study, the pressure distribution and flow coefficient of a globe valve are investigated with a series of experiments conducted in a flow test loop. The experiments are performed on a three-inch model test valve from an eight-inch ANSI (American National Standards Institute) B16.11-Class 2500# prototype globe valve with various pump speeds and full range of valve openings. Both inherent and installed flow characteristics are measured, and the results show that the flow coefficient depends not only on the valve geometry and valve opening but also on the Reynolds number. When the Reynolds number exceeds a certain value, the flow coefficients are stable. In addition, the pressures at different positions in the upstream and the downstream of the valve are measured and compared with recommendation per ANSI/ISA-75.01 standard. The results show that, in single-phase flow, the discrepancies in pressure between different measurement locations within close range of 10 nominal diameter from the valve are inconsiderable
An Ecological Momentary assessment Study to Examine Covariates and Effects of Concurrent and Simultaneous Use of Electronic Cigarettes and Marijuana among College Students
INTRODUCTION: The prevalence of concurrent and simultaneous use of e-cigarette and marijuana among college students is high. Yet, the literature was mainly based on cross-sectional surveys with emphasis on the smoking route. This is the first ecological momentary assessment (EMA) study that examined the vaping route of nicotine-marijuana co-use and the associated short-term psychological effects.
METHODS: This study recruited 686 college student e-cigarette users to participate in an on-line survey and 7-day EMA. Frequent marijuana users (247) - using marijuana weekly or daily - were compared with infrequent/non-users (439) on academic performance, e-cigarette use patterns, and dependence and respiratory symptoms. EMA data from the frequent users were used to study the association between marijuana vaping and e-cigarette consumption and the short-term psychological effects of e-cigarette and marijuana use.
RESULTS: The results show that e-cigarette users who frequently used marijuana tended to have lower academic performance, be involved in higher-risk use patterns, and have higher levels of e-cigarette dependence, marijuana problems, and respiratory symptoms, compared to infrequent/non-users. Marijuana vaping was associated with a higher level of e-cigarette consumption. E-cigarette use and marijuana use were both associated with higher levels of positive affect, physiological sensation, and craving for e-cigarettes. While marijuana use was linked to a lower level of negative affect, e-cigarette use did not have a significant effect. Further, none of the interaction effects between e-cigarette and marijuana use on psychological states were significant.
CONCLUSIONS: The results showed additive effects of e-cigarette and marijuana use although the hypothesized synergistic effects were not supported
Green Tea Consumption and Stomach Cancer Risk: A Meta-Analysis
OBJECTIVES: Green tea has been suggested to have a chemopreventive effect against various cancers including stomach cancer. The aim of this study is to elucidate the relationship between green tea consumption and stomach cancer risk by meta-analysis.
METHODS: Eighteen observational studies were identified using MEDLINE, THE COCHRANE LIBRARY, RISS, and a manual search. Summary relative risks/odds ratios (RR/ORs) for the highest versus non/lowest green tea consumption levels were calculated on the basis of fixed and random effect models. Subgroup analyses were used to examine heterogeneity across the studies.
RESULTS: The combined results indicate a reduced risk of stomach cancer with intake of green tea (RR/OR=0.86, 95% CI=0.74-1.00). Subgroup analysis with six studies that reported differences between the highest and lowest consumption levels equal to or greater than five cups/day revealed a statistically significant protective effect (RR/OR=0.68, 95% CI=0.53-0.87).
CONCLUSION: Green tea appears to play a protective role against the development of stomach cancer. The results also suggest that a higher level of green tea consumption might be needed for a clear preventive effect to appear. This conclusion, however, should be interpreted with caution because various biases can affect the results of a meta-analysis.ope
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