• Journal of Ocean Engineering and Technology
• /
• v.27 no.1
• /
• pp.80-84
• /
• 2013

This study is to develop the simplified formulae for added mass coefficient of a 2-D floating body with a semi-circle section in a finite water depth. The semi-circle floating body may represent a simplified midship section transformed by Lewis form, which can be used for the ship motion analysis by strip theory. Since the added mass coefficient varies with motion frequencies and sea bottom effect, the correction factor representing the effect of water depth and frequencies is developed for accurate prediction of added mass. Using a two-dimensional numerical wave tank (NWT) technique based on the boundary element method (BEM) including sea bottom boundary the reference values of added mass are calculated to develop the correction factor. For verification and effectiveness of the formulae, the predicted added mass coefficients for various frequencies and water depth ratios are compared with the calculated values from NWT technique.

• Journal of Korean Academy of Nursing
• /
• v.38 no.4
• /
• pp.629-638
• /
• 2008

Purpose: This was a methodological research to develop an instrument to assess the emotional response of family members of physically restrained patients. Methods: A primary instrument with 68 questions was developed based on literature review and semi-structured interviews with family members. A group of experts revised individual questions and removed 4 irrelevant questions. This secondary instrument, then, was tested with 199 family members of physically restrained patients in intensive care units of a university hospital. The validity and reliability of the instrument were tested by factor analysis. Results: After item analysis, 3 questions with a correlation coefficient under .30 were discarded and the questions with a factor loading under .45 on Varimax Rotation were also removed. After factor analysis on the final 37 questions, 7 factors were identified; avoidance, shock, helplessness, grudge, depression, anxiousness, and acceptance. The total variance explained was 55.63%. The reliability of this instrument was 0.93 of Cronbach's alpha. Conclusion: This instrument was statistically reliable and valid to measure family's emotional response to physical restraints of the patients. This instrument can be useful in assessing the effects of nursing interventions for family members of restrained patients.

• Journal of Families and Better Life
• /
• v.28 no.5
• /
• pp.89-100
• /
• 2010

The purpose of this study was to develop a "Korean Childcare Teacher's Job Satisfaction Scale"(KCTJSS) and to evaluate its reliability and validity. KCTJSS was 72 items and 6 point Likert scale. Participants consisted of 211 childcare teachers by purposive sampling. Results were as follows: First, Exploratory factor analysis resulted in 40 items composed of 6 factors : The principal's childcare center operation system, working environments and welfare, social recognition, amount of work and time management, relationships with co-workers, relationships with parents. Second, the confirmatory factor analysis supported a 6 factor structure. Third, Criterion-related validity was confirmed by significant correlations of the present scale with Early Childhood Job Satisfaction Survey(Jorde-Bloom, 1989). Fourth, the reliability of factors using Cronbach's ${\alpha}$ appeared high, ranging from .83 to .93.

• BMB Reports
• /
• v.48 no.9
• /
• pp.525-530
• /
• 2015

Activation of the Wnt/β-catenin pathway plays a pathogenic role in age-related macular degeneration (AMD) and is thus a potential target for the development of therapeutics for this disease. Here, we demonstrated that Wnt5a antagonized β-catenin response transcription (CRT) induced with Wnt3a by promoting β-catenin phosphorylation at Ser33/Ser37/Thr41 and its subsequent degradation in human retinal pigment epithelial (RPE) cells. Wnt5a decreased the levels of vascular endothelial growth factor (VEGF), tumor necrosis factor-α(TNF-α), and nuclear factor-κB (NF-κB), which was up-regulated by Wnt3a. Furthermore, Wnt5a increased E-cadherin expression and decreased cell migration by down-regulating Snail expression, thereby abrogating the Wnt3a-induced epithelial-mesenchymal transition (EMT) in human RPE cells. Our findings suggest that Wnt5a suppresses the pathogenic effects of canonical Wnt signaling in human RPE cells by promoting β-catenin phosphorylation and degradation. Therefore, Wnt5a has significant therapeutic potential for the treatment of AMD. [BMB Reports 2015; 48(9): 525-530]

• BMB Reports
• /
• v.51 no.2
• /
• pp.73-78
• /
• 2018

Vascular endothelial growth factor and its receptor (VEGF-VEGFR) system play a critical role in the regulation of angiogenesis and lymphangiogenesis in vertebrates. Each of the VEGF has specific receptors, which it activates by binding to the extracellular domain of the receptors, and, thus, regulates the angiogenic balance in the early embryonic and adult stages. However, de-regulation of the VEGF-VEGFR implicates directly in various diseases, particularly cancer. Moreover, tumor growth needs a dedicated blood supply to provide oxygen and other essential nutrients. Tumor metastasis requires blood vessels to carry tumors to distant sites, where they can implant and begin the growth of secondary tumors. Thus, investigation of signaling systems related to the human disease, such as VEGF-VEGFR, will facilitate the development of treatments for such illnesses.

• BMB Reports
• /
• v.51 no.2
• /
• pp.57-58
• /
• 2018

An accurate diagnostic marker for detecting early-stage hepatocellular carcinoma (eHCC) is clinically important, since early detection of HCC remarkably improves patient survival. From the integrative analysis of the transcriptome and clinicopathologic data of human multi-stage HCC tissues, we were able to identify barrier-to-autointegration factor 1 (BANF1), procollagen-lysine, 2-oxoglutarate 5-dioxygenase 3 (PLOD3) and splicing factor 3b subunit 4 (SF3B4) as early HCC biomarkers which could be detected in precancerous lesions of HCC, with superior capabilities to diagnose eHCC compared to the currently popular HCC diagnostic biomarkers: GPC3, GS, and HSP70. We then showed that SF3B4 knockdown caused G1/S cell cycle arrest by recovering $p27^{kip1}$ and simultaneously suppressing cyclins, and CDKs in liver cancer cells. Notably, we demonstrated that aberrant SF3B4 overexpression altered the progress of splicing progress of the tumor suppressor gene, kruppel like factor 4 (KLF4), and resulted in non-functional skipped exon transcripts. This contributes to liver tumorigenesis via transcriptional inactivation of $p27^{kip1}$ and simultaneous activation of Slug genes. Our results suggest that SF3B4 indicates early-stage HCC in precancerous lesions, and also functions as an early-stage driver in the development of liver cancer.

• Journal of Environmental Science International
• /
• v.26 no.12
• /
• pp.1333-1339
• /
• 2017

Coal-fired power plants emit various Particulate Matter(PM) at coal storage pile and ash landfill as well as the stack, and affect the surrounding environment. Field Emission Scanning Electron Microscopy and Energy Dispersive X-ray analyzer(FE-SEM/EDX) were used to develop identification factor and the physico-chemical analysis of PM emitted from a power plant. In this study, three samples of pulverized coal, bottom ash, and fly ash were analyzed. The pulverized coal was spherical particles in shape and the chemical composition of C-O-Si-Al and C/Si and C/Al ratios were 200~300 on average. The bottom ash was spherical or non-spherical particles in shape, chemical composition was O-C-Si-Al-Fe-Ca and C/Si and C/Al ratios were $4.3{\pm}4.6$ and $8.8{\pm}10.0$. The fly ash was spherical particles in shape, chemical composition was O-Si-Ai-C-Fe-Ca and C/Si and C/Al ratios were $0.5{\pm}0.2$ and $0.8{\pm}0.5$.

• Journal of the Korean housing association
• /
• v.28 no.1
• /
• pp.19-26
• /
• 2017

The purpose of study developing Development evaluation methods of light environment for indoor of middle school based on 'Biophilia'. This study is mainly based on literary review and survey research. To construct structural questionnaire based on 'Light and Space' of Biophilic Design for well being lighting environmental evaluation. We construct structural questionnaire that have 10 evaluation factors and 60 detail evaluation items to evaluate lighting environment for indoor of middle school based on biophilia theory. To survey students' subjective evaluation, the participant of study has been selected with the total number of 232 middle school students. The data were analyzed using Multiple Regression Analysis by IBM SPSS statistics 21. The result of pearson correlation analysis between satisfaction of indoor light environment and school life satisfaction, satisfaction of the whole indoor light environment was found showing positive relationship with school life satisfaction. The results of light environmental evaluation were factor 3,6,8,9 was lower than others. This study was designed to suggesting an evaluation method of light environment of the school. Biophilia theory said when 10 evaluation factor are in harmony, light environment can be well-being. So, factor 3,6,8,9 that are important elements to increase the satisfaction of lighting environment are consider carefully for the plan of indoor lighting environment.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.1250-1251
• /
• 2008

In this study, the dielectric ceramics with low loss were investigated for high frequency application. All sample of the $Ba_5M_4O_{15}$ (M=Ta, Nb) ceramics were prepared by the conventional mixed oxide method and sintered at $1325{\sim}1575^{\circ}C$. The bulk density and dielectric constant of the $Ba_5Ta_4O_{15}$ ceramics were increased continuously with increasing of sintering temperature. The quality factor was increased in the sintering temperature of $1375{\sim}1475^{\circ}C$ but decreased at the temperature above 1475$^{\circ}C$. In the case of $Ba_5Nb_4O_{15}$ ceramics, the bulk density, dielectric constant and quality factor were increased with sintering temperature but decreased above temperature of 1400$^{\circ}C$. The dielectric constant, quality factor and temperature coefficient of the resonant frequency (TCRF) of the $Ba_5Ta_4O_{15}$ and $Ba_5Nb_4O_{15}$ ceramics, sintered at 1475$^{\circ}C$ and 1400$^{\circ}C$, were 25.15, 53105 GHz, -3.06 ppm/$^{\circ}C$ and 39.55, 28052 GHz, 5.7 ppm/$^{\circ}C$, respectively.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.942-943
• /
• 2008

The boost converter is usually used in power factor correction. The dynamic losses of its output diode are produced during the reverse recovery time. The power efficiency is decreased due to the losses and also it generates the noise. These disadvantages have been remarkably improved by ZCS and ZVS techniques of power factor improvement circuit. Some benefits lead to the achievement of higher power density and the development cost can be decreased. In this paper work, the reverse recovery suppression(RS) PFC method is used. A inductor and a diode are added into the conventional circuit. The switching device, MOSFET is turned off after the reverse recovery current has come to the zero level. The Zero Current Switching(ZCS) is implemented at that time. This power conversion technique improves the efficiency to about 1% and reduces the noise obviously. And the additional inductor can be designed using an original filter core in the circuit. The converter size is reduced effectively.