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The aim of this paper is to present a reliability modeling and analysis of a two-unit system of a continuous casting (CC) plant. Real maintenance data of a steel production plant have been used for the purpose. Three types of failures were noted: repairable, replaceable and reconditioning/reinstallation. The two-unit system is operating in parallel, on full-reduced installed capacity. Upon the unit failure, an inspection is carried out to decide the type of maintenance task to be performed. Optimized reliability indices of the plant such as mean time to system failure, availability, expected busy periods of the repairman for various maintenance tasks, expected number of visits by the repairman, expected number of repairs, replacements and reconditioning/reinstallation are obtained. Semi-Markov processes and regenerative point techniques are used for the analysis. Profit incurred to the CC plant is also evaluated and related graphs are plotted to demonstrate the results.  相似文献   
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To study oxidative stress in systemic lupus erythematosus (SLE) by estimating serum oxidised LDL (OxLDL), 8-hydroxy-2′-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and total anti-oxidant status and to correlate with SLE disease activity and disease damage. Eighty SLE patients satisfying the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) 2012 criteria and 80 healthy controls were studied. Exclusion criteria were infections, renal insufficiency, other connective tissue diseases, drug-induced lupus, smoking, alcohol consumption. Disease activity was measured by SLE disease activity index-2 K (SLEDAI), disease damage was quantified by SLICC-Damage Index (SDI). Sera was tested for OxLDL, 8-OHdG, and total antioxidant status (TAS) by double-antibody sandwich ELISA; MDA measured by Colorimetric assay. Oxidative stress markers were compared between group1- controls, group 2-mildly active SLE (SLEDAI ≤ 5), group 3- moderate to highly active SLE (SLEDAI ≥ 6). SLE patients had significantly higher MDA, 8-OHdG and lower TAS when compared to healthy controls, while OxLDL was similar in the three groups. MDA, 8-OHdG were significantly higher, TAS lower in group 3 compared to group 2. MDA had positive correlation with SLEDAI, TAS negatively correlated with SLEDAI. SLE with neuropsychiatric manifestations, vasculitis, anti-sdDNA antibodies had higher MDA, MDA/TAS ratio. SLE patients with thrombocytopenia, and vasculitis had higher OxLDL. Only OxLDL was significantly higher in those patients who have SDI > 1. SLE patients have increased oxidative stress measured by increases in MDA, 8-OHdG, and lower total antioxidant status that was associated with disease activity and some disease manifestations. However only OxLDL was associated with damage.  相似文献   
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Early Childhood Education Journal - Active engagement in music has numerous academic and social benefits for young children and music-making is included in many early childhood standards and...  相似文献   
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In this hyper-competitive era, patents are an essential input to realizing sustainable competitive advantage. However, individual differences exist in patenting filing behavior and behaviors related to commercialization of patents. This study explores these behaviors in the context of three demographic variables. The demographic variables are patenting and commercialization experiences of inventors, age and sector. Further, aspirations of these inventors are assessed using external motivators of wealth, fame, and concern for societal welfare, and internal motivators such as pragmatism. The findings of this empirical study (n = 116) suggest that sector and age determine differences in personal internal motivators more than patent commercialization experience. Implications of the study are discussed.  相似文献   
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This study investigated the influence of informational complexity and working memory capacity on problem-solving efficiency. We examined two predictions of thesituational efficiency hypothesis, which states that the efficiency of problem solving varies as a function of situational constraints. One prediction is that informational complexity affects problem-solving efficiency. A second prediction is that working memory capacity affects problem-solving efficiency. Students completed a working memory task and solved abstract and concrete syllogisms. Participants solved abstract syllogisms more accurately than concrete syllogisms and spent more time solving abstract syllogisms. Thus participants demonstrated greater problem-solving efficiency when solving concrete syllogisms. Results indicate that there is a trade-off between problem-solving accuracy and problem-solving time when information differs with respect to informational complexity, a phenomenon we refer to as theefficiency paradox. Working memory capacity did not affect accuracy or efficiency. The results support the conclusion that problem-solving efficiency is situational and a function of the complexity of information. Educational implications and directions for future research are suggested.  相似文献   
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One of the fastest growing, most discussed, and most expensive technology initiatives over the last decade has been one-to-one (1:1) computing initiatives. The purpose of this study was to examine key factors that influenced implementing and sustaining 1:1 computing initiatives from the perspective of school superintendents. Nine superintendents of established 1:1 programs were interviewed, and findings identified five themes for successful implementation and sustainability of 1:1 initiatives. (Keywords: 1:1 schools, school technology leadership, 1:1 implementation)  相似文献   
8.
In November 2012, 300 students came together in the Media School at Bournemouth University in the UK to report the US Presidential Election. Over the course of 10 days, students published 176 articles on a rolling news website, garnering more than 20,000 hits. On election night itself, students produced 10 h of live coverage on both TV and radio, airing 30 pre-recorded video packages and 35 pre-recorded radio packages. This experiential project adopted a so-called ‘live case’ methodology that encapsulated a high degree of application and a certain level of structure, which allowed for the ‘variety and uncertainty’ or reality to intervene. It also empowered and enabled students to reflect on and evaluate their individual experiences in light of their own learning styles. This paper will discuss the challenges and successes experienced during this experiential project, and will provide a nine-step guide on how others could replicate a similar project.  相似文献   
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The study compared the agreement, internal consistency, and measurement stability of the GE iDXA, BOD POD, and InBody 720. Body composition of 43 men and 37 women (31.4 ± 10.7 years; 90% Caucasian and 10% other) was assessed in triplicate using each method over two different days. Mean percent body fat (% BF) of the participants was different for all three machines (27.6 ± 10.0% [GE iDXA)] 25.6 ± 10.4% [BOD POD], and 21.3 ± 10.6% [InBody 720]; p < .05). The coefficient of variation for same day repeated measures was 1.06% (GE iDXA), 3.29% (BOD POD), and 2.97% (InBody 720). The coefficient of variation for 2-day repeated measures was 1.81% (GE iDXA), 4.61% (BOD POD), and 4.24% (InBody 720). The difference between the GE iDXA and BOD POD was within acceptable variability, while the InBody 720 significantly underestimated % BF. The internal consistency was highest for the GE iDXA, followed by the InBody 720, and then the BOD POD.  相似文献   
10.
The literature on trolling has viewed trolling as discrete instances of transgression undertaken by antagonistic individuals. We identify three main issues with current theorizations: diffuse definitions of “trolling,” blurred boundaries between trolling and other online anti-social behaviors, and the context dependency of trolling. To address these unresolved issues, we adopt a practice-based theoretical approach. Informed by this approach, we analyze trolling behaviors not as products of individuals' attitudes, values, and decisions, but rather as behaviors embedded within and occurring as part of social practices. Specifically, we conduct a practice-based theoretical analysis in a multi-site exploratory study involving online archival research and in-depth interviews with online community members. Based on this analysis, we propose that trolling be conceived as a constellation of three social practices: learning, assimilating, and transgressing. Also, we find that practices of trolling transgression can have a dual pro-social and anti-social impact in online communities.  相似文献   
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