• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.5
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• pp.533-541
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• 2021

Retaining walls have been used to prevent slope failure through resistance of earth pressure in railway, road, nuclear power plant, dam, and river infrastructure. To calculate dynamic earth pressure and determine the characteristics for seismic behavior, many researchers have analyzed the nonlinear response of ground and structure based on various numerical analyses (FLAC, PLAXIS, ABAQUS etc). In addition, seismic fragility evaluation is performed to ensure safety against earthquakes for structures. In this study, we used the FLAC2D program to understand the seismic response of the inverted T-type wall with a backfill slope, and evaluated seismic fragility based on relative horizontal displacements of the wall. Nonlinear site response analysis was performed for each site (S2 and S4) using the seven ground motions to calculate various seismic loadings reflecting site characteristics. The numerical model was validated based on other numerical models, experiment results, and generalized formula for dynamic active earth pressure. We also determined the damage state and damage index based on the height of retaining wall, and developed the seismic fragility curves. The damage probabilities of the retaining wall for the S4 site were computed to be larger than those for the S2 site.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.1
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• pp.31-41
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• 2021

The aim of this retrospective study was to evaluate the correlation between the midpalatal suture maturation and skeletal maturation in growing children aged 7 - 15 years and predict the maturational stages of the midpalatal suture corresponding to skeletal maturity assessed by the skeletal maturation indicators (SMI) and middle phalanx of the third finger (MP3) stages. The group of this retrospective study was consisted of randomly selected 132 male and 135 female in age from 7 - 15 years. The maturation of the midpalatal suture was evaluated by using images from cone-beam computed tomography (CBCT) while the skeletal age was assessed by hand-wrist radiography. CBCT images and hand-wrist radiographs used in this study were obtained from all subjects for orthodontic diagnosis before orthodontic treatment. The maturational stages of the midpalatal suture showed strong correlations with both SMI and MP3 stages. The correlation between the midpalatal suture maturation and SMI (Spearman's correlation coefficient, ϒ_S = 0.905, p < 0.05) was slightly greater than that of MP3 stages (ϒ_S = 0.830, p < 0.05). There was a positive significant correlation between the midpalatal suture maturation and chronological age (ϒ_S = 0.868,p < 0.05). CBCT for evaluation of the midpalatal suture maturational stages may be unnecessary in every pediatric patients because SMI and MP3 stages were both replaceable useful methods for assessing maturation of the midpalatal suture before orthopedic treatment. In this retrospective study, the diagnostic reliability of the SMI method for estimating midpalatal suture maturation showed better reliability than the MP3 method.

• Korean Journal of Labor Studies
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• v.24 no.2
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• pp.29-59
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• 2018

This paper examines the achievements and limitations of the Moon Jae-In administration's first-year policies on non-standard employment in the public sector of Korea. The most remarkable achievement was that the transition rate of non-standard to standard positions reached the highest historical level of 42.1 percent, mainly by including for the first time temporary agency workers as a target of those policies. There also have been many steps taken to relax the qualification for transition, reduce the number of exception clauses, and expand union participation. In contrast, policy measures to address problems of low wages and inequality were very limited and not significantly different from those of previous administrations. As a result, the success of the policy paradigm shift pursued by Moon's administration will be determined by how aggressive measures are being taken in the next policy steps to improve such problems of low wages and inequality.

• Journal of vocational education research
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• v.36 no.4
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• pp.1-20
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• 2017

The purpose of this study is to identify the cognitive and psychological precedence factors of career preparation behaviors of university students and to clarify the structural relationships between the variables. First, the effects of reflective learning on university students' career preparation behaviors were examined and the mediating effect of grit between reflective learning and career preparation behavior was verified. The research analyzed 307 university students in the 3rd and 4th year. The results of the study have shown that the reflective learning had a significant positive relationship with all variables of grit and career preparation behavior, but non-reflective learning have an insignificance relationship with all the main variables. In addition, reflective learning has a direct positive effect on career preparation behavior, and grit has a mediating effect on the relationship between reflective learning and career preparation behavior. The results of this study indicate that the more original variables are further identified and extended to improve career preparation behaviors of university students. It is significant that they are provided with the basic data for the development of career and job preparation education programs that can be applied in the university education field. In addition, it has been confirmed that it is important for university students to improve their ability to critically reflect on themselves, their surroundings and circumstances in order to keep them engaged and to maintain their interests. Moreover, higher education institutions should provide fundamental and extensible method of practice and educational environment.

• Pediatric Infection and Vaccine
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• v.25 no.3
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• pp.141-147
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• 2018

Purpose: Despite effectiveness and safety of maternal tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccination, Tdap vaccination coverage during pregnancy remains quite low. We assessed the knowledge, attitude and practice on maternal Tdap vaccination among pregnant women. Methods: This study was a cross-sectional survey of pregnant women who visited tertiary obstetrics and gynecologic units in Seoul and Gyeonggi province of Korea. Individual questionnaires were administered to assess knowledge, attitude and practice on maternal immunization with Tdap. Results: The questionnaires were completed by 184 pregnant women; 158 (86%) had not received information from doctors about pertussis and Tdap, and 166 (90%) did not know the need for Tdap vaccination. Only 7% of pregnant women unlikely to receive Tdap vaccine during current pregnancy answered 3 or more of the 5 knowledge-based questions correctly. By logistic regression analysis, recommendation by doctor (adjusted odd ratio [OR], 236.2; 95% confidence interval [CI], 12.6-4,432), belief that the vaccine is effective (adjusted OR, 40.21; 95% CI, 2.35-687.7), and belief that the vaccine is safe (adjusted OR, 19.83; 95% CI, 1.54-255.9) were significantly important factors to respondents' intention to be vaccinated. Conclusions: Most pregnant women seem to be neither recommended nor adequately informed about Tdap vaccination. Information given by health care professionals is very important to increase Tdap coverage among pregnant women.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.3
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• pp.27-38
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• 2019

Recently, domestic universities have emphasized career path to start-up through entrepreneurial self-efficacy (ESE) and entrepreneurship. The purpose of this study is to investigate the effect of ESE on entrepreneurship of university students. Also we examine the moderating effects of entrepreneurial education and career uncertainty between ESE and entrepreneurship. Research sample consisted of 236 university students in Cheonan city. The results of this research is as follows: First, ESE showed a positive effects on entrepreneurship. Second, the moderating effect of entrepreneurial education was significant on the relationship between ESE and entrepreneurship. In other words, university students with a higher entrepreneurial education showed higher entrepreneurship when ESE was lower. But students with a lower entrepreneurial education showed higher entrepreneurship when ESE was higher. Finally, the interaction effects of career uncertainty was confirmed in relationship between ESE and entrepreneurship. In other words, university students with a higher career uncertainty showed higher entrepreneurship when ESE was higher. But students with a lower career uncertainty showed higher entrepreneurship when ESE was lower. In order to improve the entrepreneurship of the pre-founders, it is necessary to strengthen the behavior control of university students by enhancing the ESE. Also, the improvement of entrepreneurship of pre-founders should strengthen the ESE of university students, and should complement systematic and effective entrepreneurship education. In particular, we should provide the stability for career decision by eliminating uncertainty about the career path of university students.

• Fire Science and Engineering
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• v.33 no.2
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• pp.114-123
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• 2019

The paper relates to a study on the changes in performance of insulation sheath resulting from accelerated degradation of IV and HIV insulated wire. To assume insulation degradation of IV and HIV insulated wire, accelerated life tests using Arrhenius equation were conducted among accelerated life test models, and experimental samples of 0 year, 10 years, 20 years, 30 years, and 40 years in equivalent life were produced. Whereas the maximum tensile load were increased as accelerated degradation of IV and HIV insulated wire progressed, elongation percentage, rupture time, and flexibility of insulated wires were found to be gradually reduced. According to the additional surface analysis results for the insulated wires per equivalent life using a scanning electron microscope, mechanical properties of the insulator were observed to be reduced as insulation degradation resulting from aging progressed since phenomena such as formation of crystalline structures and perforation, etc. occurred on the sample surface with progression of accelerated degradation. Consequently, institutional replacement of insulated wires and preparation of repair times considering performance degradation of the insulator installed inside buildings are considered necessary in order to prevent in advance the risks of electrical fire resulting from degradation in insulation performance.

• Journal of Veterinary Clinics
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• v.36 no.1
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• pp.7-14
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• 2019

In South Korea, six large outbreaks of highly pathogenic avian influenza (HPAI) have occurred since the first confirmation in 2003 from chickens. For the past 15 years, HPAI outbreaks have become an annual phenomenon throughout the country and has extended to wider regions, across rural and urban environments. An understanding of the spatial epidemiology of HPAI occurrence is essential in assessing and managing the risk of the infection; however, local spatial variations of relationship between HPAI incidences in Korea and related risk factors have rarely been derived. This study examined whether spatial heterogeneity exists in this relationship, using a geographically weighted Poisson regression (GWPR) model. The outcome variable was the number of HPAI-positive farms at 252 Si-Gun-Gu (administrative boundaries in Korea) level notified to government authority during the period from January 2014 to April 2016. This response variable was regressed to a set of sociodemographic and topographic predictors, including the number of wild birds infected with HPAI virus, the number of wintering birds and their species migrated into Korea, the movement frequency of vehicles carrying animals, the volume of manure treated per day, the number of livestock farms, and mean elevation. Both global and local modeling techniques were employed to fit the model. From 2014 to 2016, a total of 403 HPAI-positive farms were reported with high incidence especially in western coastal regions, ranging from 0 to 74. The results of this study show that local model (adjusted R-square = 0.801, AIC = 954.5) has great advantages over corresponding global model (adjusted R-square = 0.408, AIC = 2323.1) in terms of model fitting and performance. The relationship between HPAI incidence in Korea and seven predictors under consideration were significantly spatially non-stationary, contrary to assumptions in the global model. The comparison between global Poisson and GWPR results indicated that a place-specific spatial analysis not only fit the data better, but also provided insights into understanding the non-stationarity of the associations between the HPAI and associated determinants. We demonstrated that an empirically derived GWPR model has the potential to serve as a useful tool for assessing spatially varying characteristics of HPAI incidences for a given local area and predicting the risk area of HPAI occurrence. Considering the prominent burden of HPAI this study provides more insights into spatial targeting of enhanced surveillance and control strategies in high-risk regions against HPAI outbreaks.

• Journal of Energy Engineering
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• v.27 no.4
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• pp.27-35
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• 2018

The passive containment cooling system (PCCS) has been designed to remove the released decay heat during the accident by means of the condensation heat transfer phenomenon to guarantee the safety of the nuclear power plant. The heat removal performance of the PCCS is mainly governed by the condensation heat transfer of the steam-air mixture. In this study, the heat removal performance of the PCCS was evaluated by using the MARS-KS code with a new empirical correlation for steam condensation in the presence of a noncondensable gas. A new empirical correlation implemented into the MARS-KS code was developed as a function of parameters that affect the condensation heat transfer coefficient, such as the pressure, the wall subcooling, the noncondensable gas mass fraction and the aspect ratio of the condenser tube. The empirical correlation was applied to the MARS-KS code to replace the default Colburn-Hougen model. The various thermal-hydraulic parameters during the operation of the PCCS follonwing a large-break loss-of-coolant-accident were analyzed. The transient pressure behavior inside the containment from the MARS-KS with the empirical correlation was compared with calculated with the Colburn-Hougen model.

• Journal of Life Science
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• v.28 no.11
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• pp.1379-1385
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• 2018

Glycans are attached to proteins as in glycoproteins and proteoglycans. They are found on the exterior surface of cells. O- and N-linked glycans are very common in eukaryotic cells but may also be found in prokaryotes. The interaction of cell surface glycans with complementary glycan binding proteins located on neighboring cells, other cell types, pathogens like virus, or bacteria is crucial in biologically and biomedically important processes like pathogen recognition, cell migration, cell-cell adhesion, development, and infection. Their implication in pathological condition, suggests an important role for glycans as disease markers. In addition, a great amount of research has been shown that appropriate glycosylation of a recombinant therapeutic protein is critical for product solubility, stability, pharmacokinetics and pharmacodynamics, bioactivity, and safety. Besides, cancer-associated glycosylation changes often involve sialic acid in glycan branch which play important roles in cell-cell interaction, recognition and immunological response. This review aims at giving a comprehensive overview of the glycan's biological function and describing the relevance among the glycosylation, disease diagnosis and treatment methods. Furthermore, the high-throughput analytic methods available to measure the profile changing patterns of glycan in the blood serum as well as possible underlying biochemical mechanisms.