• Journal of Mechanical Science and Technology
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• v.20 no.8
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• pp.1309-1320
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• 2006

The linear instability of reacting shear flow is analyzed with special emphasis on the effects of the heat release and variable transport properties. Both analytic profiles and laminar solutions of the boundary-layer equations are used as base flows. The growth rates of the instabilities are sensitive to the laminar profiles, differing by more than a factor of 2 according to which profile is used. Thus, it is important to base the analysis on accurate laminar profiles. Accounting for variable transport properties also changes the mean profiles considerably, and so including them in the computation of the laminar profiles is equally important. At larger heat release, two modes that are stronger in the outer part of the shear layer have the highest growth rates; they also have shorter wavelengths than the center mode.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.13 no.1
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• pp.48-63
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• 1984

Standard Building Operation Conditions(SBOC) is to describe typical conditions under which a building would operate during the coulee of a day In order to develop SBOC profiles for office building, we surveyed the operating conditions of randomly selected 20 existing office buildings in Seoul by means of enquetes, and made SBOC profiles. SBOC profiles consist of human occupancy profile, light ins usage profile, system schedule and domestic hot water profile etc. SBOC profiles will be used as input data of DOE-2 computer program to estimate DER(Design Energy Requirements) and to develop EBL (Energy Budget Level), SBOC profiles are not meant to be exact description of how a building will actually be used by its respective users. Rather they are intended to be reasonable typical project ions of how buildings might be used.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1250-1264
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• 2023

This paper presents approximate in-depth residual stress and plastic strain profiles for laser-peened alloy 600 surface via FE analysis. In approximations, effects of the initial welding residual stress and the number of shots are quantified. Based on FE analysis results, residual stress profiles are quantified by two variables; the maximum difference in stress before and after LSP, and the depth up to which the compressive residual stress exists. Plastic strain profiles are quantified by one variable, the maximum equivalent plastic strain at the surface. The proposed profiles are validated by comparing with published LSP experimental results for welded plates. Effects of the initial welding residual stress and the number of shots on these variables are discussed. The proposed profile can be directly applied to predict the mitigation effect of LSP on PWSCC and to efficiently perform structural integrity assessment of laser peened nuclear components.

• Educational Technology International
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• v.18 no.1
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• pp.27-47
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• 2017

Smart devices have a variety of affordances to foster meaningful learning in elementary school. For the design of smart learning environments, more research is needed to understand students' smart device usage and their perception of learning with smart devices. In order to capture smart device usage profiles among elementary school students in South Korea, this study carried out Latent Profile Analysis with three constructs: information search, communication, and study. Participants (n=253), who ranged from the fourth to the sixth grade students, were classified into three profiles of smart device usage: low-activity, communication, and high-activity groups. The smart device usage profiles varied depending on smartphone usage experience, and the profiles were significantly related with smart device addiction, not with smart device usage ability. Perceptions of smart education were also significantly associated with the profiles. The high-activity group showed more positive attitudes toward smart education than the others, but no significant difference was found in regard to negative attitudes. Based on the findings, this study discussed implications for the use of smart devices in elementary school.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.2
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• pp.136-142
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• 2015

The shell and tube heat exchanger is an essential part of a power plant for recovering transfer heat between the feed water of a boiler and the wasted heat. The baffles are also an important element inside the heat exchanger. Internal materials influence the flow pattern in the bed. The influence of baffles in the velocity profiles was observed using a three-dimensional PIV (Particle Image Velocimetry) around baffles in a horizontal circular tube. The velocity of the particles was measured before the baffle and between them in the test tube. Results show that the velocity vectors near the front baffle flow along the vertical wall, and then concentrate on the upper opening of the front baffle. The velocity profiles circulate in the front and rear baffle. These profiles are related to the Reynolds number (Re) or the flow intensity. Velocity profiles at lower Re number showed complicated mixing to obtain the velocities and concentrate on the lower opening of the rear baffle as front wall. Numerical simulations were performed to investigate the effects of the baffle and obtain the velocity profiles between the two baffles. In this study, a commercial CFD package, Fluent 6.3.21 with the turbulent flow modeling, k-${\epsilon}$ are adopted. The path line and local axial velocities are calculated between two baffles using this program.

• Korean Journal of Child Studies
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• v.31 no.5
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• pp.193-210
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• 2010

This study explored the common response profiles in the narrative stories of typically developing 5 year-old Korean Children. Fourteen story stems from the MacArthur Story Stem Battery (MSSB, Bretherton, Oppenheim, & the MacArthur Story Stem Network, 1990) were administered to 156(85 boys and 71 girls) children recruited from 8 Kindergartens in the Seoul and Gyung-gi areas. The children's responses were aggregated into 5 dimensions, based on content themes and performance scores which included emotions expressed and narrative coherence using the MacArthur Narrative Coding System (Robinson, Mantz-Simmions, Macfie, & MacArthur Narrative Working Group, 2004). Data were analyzed by means of cluster analysis. 5 response profiles emerged over the course of this research : Prosocial, Anxiety, Dysregulated aggression, Anxious/Avoidance, and Avoidance profiles. When 14 story stems were grouped into 3 story contexts (stories included interpersonal conflicts, moral conflicts, and empathy) and were analyzed separately according to the story contexts, 3 common profiles (a Prosocial profile, a Constrained profile and an Anxiety profile) emerged across the story contexts, however, there were additional, unique profiles for each of the story contexts.

• Mass Spectrometry Letters
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• v.1 no.1
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• pp.13-16
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• 2010

The active components in a plant extract can be represented as mass profiles. We introduce here a new, multi-compound discovery method known as Scaling of Correlations between Activity and Mass Profiles (SCAMP). In this method, a correlation coefficient is used to quantify similarities between the extract activity and mass profiles. The method was evaluated by first measuring the anti-oxidation activity of eleven fractions of an Astragali Radix extract using DPPH assays. Next, 15 T Fouriertransform ion cyclotron resonance (FT-ICR) MS was employed to generate mass profiles of the eleven fractions. A comparison of correlation coefficients indicated two compounds at m/z 285.076 and 286.076 that were strong antioxidants. Principal component analyses of these profiles yielded the same result. FT-ICR MS, which offers a mass resolving power of 500,000, was used to discern isotopic fine structures and indicated that the molecular formula corresponding to the peak at m/z 285.076 was $C_{16}H_{13}O_5$. SCAMP in combination with high-resolution MS can be applied to any type of mixture to study pharmacological activity and is a powerful tool for active compound discovery in plant extract studies.

• Human Ecology Research
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• v.61 no.3
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• pp.335-348
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• 2023

The purpose of this study was to identify: (a) the latent profiles of the difficulties associated with the schoolto-work transition (decline in confidence, mood swings, family disagreements, the burdens of familial expectations, economic hardship, and a lack of support) made by university students, (b) predictors (gender, age, grade, university location, co-residence with parents on weekdays, monthly household income, and parental educational attainment) of these profiles, and (c) how the profiles were associated with mental wellbeing. The participants of this study were 311 senior or above students (164 males and 147 females) under the age of 29, who were unmarried and preparing for employment. The findings of this study were as follows. First, the latent profile analysis revealed three distinct profiles: the "low overall difficulties" type (25.4%), the "moderate overall difficulties" type (49.9%), and the "high overall difficulties" type (24.7%). Second, the factors that predicted each profile included gender, age, co-residence with parents on weekdays, monthly household income, and parental educational attainment. Third, the "low overall difficulties" type demonstrated the highest level of mental well-being (emotional, social, and psychological well-being). This study was significant for examining the latent profiles of the difficulties associated with the school-to-work transition made by university students preparing for employment, while also exploring their mental well-being. Based on the results of this study, practical implications, limitations, and suggestions for further study were discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1481-1492
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• 2012

The interaction of the genes involved in intestinal development is the molecular basis of the regulatory mechanisms of intestinal development. The objective of this study was to identify the significant pathways and key genes that regulate intestinal development in Landrace piglets, and elucidate their rules of operation. The differential expression of genes related to intestinal development during suckling time was investigated using a porcine genome array. Time sequence profiles were analyzed for the differentially expressed genes to obtain significant expression profiles. Subsequently, the most significant profiles were assayed using Gene Ontology categories, pathway analysis, network analysis, and analysis of gene co-expression to unveil the main biological processes, the significant pathways, and the effective genes, respectively. In addition, quantitative real-time PCR was carried out to verify the reliability of the results of the analysis of the array. The results showed that more than 8000 differential expression transcripts were identified using microarray technology. Among the 30 significant obtained model profiles, profiles 66 and 13 were the most significant. Analysis of profiles 66 and 13 indicated that they were mainly involved in immunity, metabolism, and cell division or proliferation. Among the most effective genes in these two profiles, CN161469, which is similar to methylcrotonoyl-Coenzyme A carboxylase 2 (beta), and U89949.1, which encodes a folate binding protein, had a crucial influence on the co-expression network.

• Nutrition Research and Practice
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• v.9 no.1
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• pp.49-56
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• 2015

BACKGROUND/OBJECTIVES: Glutathione S-transferase (GST) forms a multigene family of phase II detoxification enzymes which are involved in the detoxification of reactive oxygen species. This study examines whether daily supplementation of kale juice can modulate blood pressure (BP), levels of lipid profiles, and blood glucose, and whether this modulation could be affected by the GSTM1 and GSTT1 polymorphisms. SUBJECTS/METHODS: 84 subclinical hypertensive patients showing systolic BP over 130 mmHg or diastolic BP over 85 mmHg received 300 ml/day of kale juice for 6 weeks, and blood samples were collected on 0-week and 6-week in order to evaluate plasma lipid profiles (total cholesterol, triglyceride, HDL-cholesterol, and LDL-cholesterol) and blood glucose. RESULTS: Systolic and diastolic blood pressure was significantly decreased in all patients regardless of their GSTM1 or GSTT1 polymorphisms after kale juice supplementation. Blood glucose level was decreased only in the GSTM1-present genotype, and plasma lipid profiles showed no difference in both the GSTM1-null and GSTM1-present genotypes. In the case of GSTT1, on the other hand, plasma HDL-C was increased and LDL-C was decreased only in the GSTT1-present type, while blood glucose was decreased only in the GSTT1-null genotype. CONCLUSIONS: These findings suggest that the supplementation of kale juice affected blood pressure, lipid profiles, and blood glucose in subclinical hypertensive patients depending on their GST genetic polymorphisms, and the improvement of lipid profiles was mainly greater in the GSTT1-present genotype and the decrease of blood glucose was greater in the GSTM1-present or GSTT1-null genotypes.