• Journal of Information Technology Application
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• v.3 no.3
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• pp.91-106
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• 2001

We propose a software-reliability growth model incoporating the amount of uniform and Weibull testing efforts during the software testing phase in this paper. The time-dependent behavior of testing effort is described by uniform and Weibull curves. Assuming that the error detection rate to the amount of testing effort spent during the testing phase is proportional to the current error content, the model is formulated by a nonhomogeneous Poisson process. Using this model the method the data analysis for software reliability measurement is developed. The optimum release time is determined by considering how the initial reliability R($\chi$ 0) would be. The conditions are ($R\chi$ 0)＞$R_{o}$ , $P_{o}$ ＞R($\chi$ 0)＞ $R_{o}$ $^{d}$ and R($\chi$ 0)＜$R_{o}$ $^{d}$ for uniform testing efforts. deal case is $P_{o}$ ＞($R\chi$ 0)＞ $R_{o}$ $^{d}$ Likewise, it is ($R\chi$ 0)$\geq$$R_{o}$ , $R_{o}$ ＞($R\chi$ 0)＞R(eqation omitted) and ($R\chi$ 0)＜R(eqation omitted)for Weibull testing efforts. Ideal case is $R_{o}$ ＞ R($\chi$ 0)＞ R(eqation omitted).

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.215-219
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• 2020

In this study, nanoporous iron oxide layers were fabricated by the anodization of 304 series stainless steel. K₂HPO₄/glycerol solution was used as an electrolyte for anodization. We investigated the anodization behavior according to various parameters such as electrolyte concentration, reaction temperature, applied voltage, and reaction time. As a result of anodization, we confirmed that the anodic growth rate of oxide layer on 304 series stainless steel increased with increasing the electrolyte temperature and applied potential. In order to form well-ordered porous nanostructures, the electrolyte temperature was at 160 ℃, and the applied potential was at 30 V in 10 wt% K₂HPO₄/glycerol electrolyte.

• Korean Journal of Head & Neck Oncology
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• v.13 no.1
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• pp.74-80
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• 1997

We have experienced 5 cases of unusual well differentiated thyroid carcinoma with insular component during the past 5 years. 4 cases were presented with cervical masses but I case (patient 2.) was initiallty with lung and brain metastasis. The tumors from 4 cases showed invasive growths but that of 1 cases(patient 1.) showed intrathyroidal. Total thyroidectomy and cervical lymphnode dissection(CCND or RND) was performed in 4 cases but only RND was performed in spite of mediastinal metastasis of the tumor in patient 5 under the patient's choice. During the follow-up period, we also performed radical nephrectomy and metastatectomy for the kidney and iliac bone metastasis respectively, in patint 2. Microcsopically, the tumors showed the insular growth patterns, focally(less than 50%) in 3 cases and predominantly(more than 75%) in 2 cases. And the insular componentas were combined with papillary carcinoma in 2 cases and follicular carcinoma in 3 cases. Cervical lymphnode metastases were confirmed in 4 cases. Patient 2 died of disease with metastases to lung, brain, bone and kidney, 52 months after initial therapy. Patient 1, 3 and 4 are alive and have no recurrence and distant metastasis. Patient 5 is also alive with the mediastinal metastasis. In our experience, the well differentiated thyroid carcinomas with insular component showed characteristic histologic features, aggressive behavior in initial presentation and unfavorable prognosis regardless of the percentage of the insular component.

• Journal of Nutrition and Health
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• v.23 no.3
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• pp.179-186
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• 1990

Nitrogen(N) concentrations of human milk in various fractions, such as total, protein, nonprotein, whey protein and casein were determined at 2-3 days, 1, 2, 4, 6 and 12 weeks of postpartum. significant decreases in total N, nonprotein N, protein N, whey protein N and casein N were found with time postpartum. Total nitrogen decreased from 401mg/dl at 2-3 days to 211mg/dl at 12 week. Whey protein nitrogen was found to contribute to the total nitrogen decrease with time. The percentage of nonprotein nitrogen was 13% in colostrum and 17-18% in mature milk. The proportions of whey protein and casein nitrogen were 55:45 at 2-3 days and 34:66 at 12 week postpartum. These determinations will provide the basic information on the variability of nitrogen components as lactation proceed.

• Restorative Dentistry and Endodontics
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• v.40 no.1
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• pp.50-57
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• 2015

Objectives: The usage of medicinal plants as natural antimicrobial agents has grown in many fields including dental medicine. The aim of this in vitro study was three-fold: (i) to determine the chemical compositions of the Ferula gummosa essential oil (FGEO), (ii) to compare the antimicrobial efficacy of the oil with sodium hypochlorite (NaOCl) and chlorhexidine (CHX), (iii) to assess the toxic behavior of FGEO in different concentrations compared to 5% NaOCl and 0.2% CHX. Materials and Methods: Gas chromatography/mass spectrometry (GC/MS) was used to determine the chemical compositions of the oil. The disk diffusion method and a broth micro-dilution susceptibility assay were exploited to assess the antimicrobial efficacy against Enterococcus faecalis, Staphylococcus aureus, Streptococcus mitis, and Candida albicans. The cytocompatibility of the FGEO was assessed on L929 fibroblasts, and compared to that of NaOCl and CHX. Results: Twenty-seven constituents were recognized in FGEO. The major component of the oil was ${\beta}$-pinene (51.83%). All three irrigants significantly inhibited the growth of all examined microorganisms compared to the negative control group. FGEO at $50{\mu}g/mL$ was effective in lower concentration against Enterococcus faecalis than 5% NaOCl and 0.2% CHX, and was also more potent than 0.2% CHX against Candida albicans and Staphylococcus aureus. FGEO was a cytocompatible solution, and had significantly lower toxicity compared to 5% NaOCl and 0.2% CHX. Conclusions: FGEO showed a promising biological potency as a root canal disinfectant. More investigations are required on the effectiveness of this oil on intracanal bacterial biofilms.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.05a
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• pp.604-607
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• 2018

From the last past decade, the Internet of Thing (IoT) area has attracted a lot of attention from researchers. It is said to be a promising technology with great impact in people life, since it redefines the relationship objects have with Human and between themselves. It allows objects to gather data from the real world and communicate with others through the internet. This enabled many opportunities for service providers, companies, factories, environmental monitoring, healthcare, smart cities, and soon. Therefore, today, IoT is densely used in various domains of life, and knows an exponential growth. However, although many advancements have been achieved, several challenges keep causing issues and still need to be overcome. This paper gives an overview on the current trend issues in IoT on which researchers are focusing. It's also explores different proposed frameworks to allow the application of cognitive computing as an integrated process of an Internet of things (IoT) systems, to bring a great advanced in the way machine may communicate with human and their surroundings. This is known as cognitive IoT (CIoT), which allows machines to produce a human-like behavior, then providing enhanced level of capabilities to IoT.

• Women's Health Nursing
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• v.16 no.2
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• pp.157-165
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• 2010

Purpose: The purpose of this study was to identify differences in Health Locus of Control (HLOC), depression, wellbeing, and Health Promoting Lifestyle Profile II (HPLP) between middle aged Korean and Korean-American women. Methods: Data from 80 Korean-American women living in Los Angeles, USA and 82 Korean women living in W-city, Korea, were collected using a self administered questionnaire including items on HLOC, HPLP, a Wellbeing Index and Major Depression Inventory. Results: There were statistically significant differences between the middle aged Koreans and Korean-Americans on mean age, education, religion, and current health insurance. Significant differences were found on HLOC (F= 2.504, p=.033) and Wellbeing (F=2.451, p=.036). The results also showed significant differences on HPLP (total HPLP, F=4.655, p=.001; physical activity, F=2.967, p=.014; nutrition, F=4.250, p=.001; spiritual growth, F=4.398, p=.001; interpersonal relations, F=2.648, p=.025; and stress management, F=5.201, p<.001) using ANCOVA. However, there were no significant differences on depression, or health responsibility in HPLP between the groups. Conclusion: Understanding middle aged women's health adjustments based on their culture will enhance the ability of health professionals to provide culturally congruent care and enable middle aged women to develop healthy lifestyles.

• Women's Health Nursing
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• v.20 no.1
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• pp.14-28
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• 2014

Purpose: This study was to identify relationships of maternal psychosocial factors including mother's mood state, childcare stress, social support and sleep satisfaction with breastfeeding adaptation and immune substances in breast milk, especially secretory immunoglobulin A (sIgA) and transforming growth factor-beta 2 (TGF-${\beta}2$). Methods: Data were collected from 84 mothers who delivered full-term infants by natural childbirth. Structured questionnaires and breast milk were collected at 2~4 days and 6 weeks postpartum. Data were analyzed using descriptive statistics, Pearson's correlation, multiple linear regression, and generalized estimating equation (GEE). Results: Scores for the breastfeeding adaptation scale were significantly related with child care stress, mood state and social support. Mother's anger was positively correlated with the level of sIgA in colostrum (p<.01). Immune substances of breastmilk was significantly influenced by time for milk collection (p<.001) and the type of breastfeeding (sIgA, p<.001, TGF-${\beta}2$, p=.003). Regression analysis showed that breastfeeding adaptation could be explained 59.1% by the type of breastfeeding, childcare stress, the Profile of Mood States, emotional support and sleep quality (F=16.67, p<.001). Conclusion: The findings from this study provide important concepts of breastfeeding adaptation program and explanation of psychosocial factors by immune substances in breast milk. Future research, specially, bio-maker research on breast milk should focus on the ways to improve breastfeeding adaptation.

• Korean Journal of Metals and Materials
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• v.49 no.10
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• pp.818-822
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• 2011

ZnO nanorods were grown on Au-coated Si substrates by vapor phase transport (VPT) at the growth temperature of $600^{\circ}C$ using a mixture of zinc oxide and graphite powders as source material. Au thin films with the thickness of 5 nm were deposited by ion sputtering. Temperature-dependent photoluminescence (PL) was carried out to investigate the optical properties of the ZnO nanorods. Five peaks at 3.363, 3.327, 3.296, 3.228, and 3.143 eV, corresponding to the free exciton (FX), neutral donor bound exciton ($D^{\circ}X$), first order longitudinal optical phonon replica of free exciton (FX-1LO), FX-2LO, and FX-3LO emissions, were obtained at low-temperature (10 K). The intensity of these peaks decreased and their position was red shifted with the increase in the temperature. The FX emission peak energy of the ZnO nanorods exhibited an anomalous behavior (red-blue-red shift) with the increase in temperature. This is also known as an "S-shaped" emission shift. The thermal activation energy for the exciton with increasing temperature in the ZnO nanorods is found to be about 26.6 meV; the values of Varshni's empirical equation fitting parameters are = $5{\times}10^{-4}eV/K$, ${\beta}=350K$, and $E_g(0)=3.364eV$.

• Journal of Biomedical Engineering Research
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• v.40 no.5
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• pp.165-170
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• 2019

Cancer cells are different from normal cells in terms of life cycle, behavior, and growth patterns. Cancer cells can migrate freely in the body through blood vessels and lymph nodes. The cancer cells easily interact with various substrates including extracellular matrix and vessels and they can differentiate in the new environment. However, it is not well known about the adhesion preference of cancer cells on the substrate and the mechanism of their interaction. In this study, we prepared the nano-, micro-patterned substrates using E-beam lithography techniques. MCF-7 cells were tested on the substrates to find out their adhesion preference. The substrates were made by polydimethylsiloxane (PDMS) with specific patterns including pillars with a diameter of 500 nm, 700 nm, $3{\mu}m$ and $5{\mu}m$. MCF-7 cells were seeded on the substrates and incubated for 24 hours. As a result, this study clearly demonstrated that the MCF-7 cells preferred 700 nm patterning.