• Development and Reproduction
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• v.21 no.2
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• pp.223-228
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• 2017

This study investigated the effect of different photoperiods (14L: 10D, 12L:12D and 10L:14D) on the gonadal development and GtH mRNA expression in the pituitary of damselfish. The results showed that gonadosomatic index (GSI) was significantly lower in shot photoperiod (10L:14D), in comparison with other photoperiodic group during the spawning season. After 60 days treatment, histological analysis of gonad tissue showed that the gonad of 10L:14D and 12L: 12D treatment groups were resting phase with spermatogonia and perinucleolus stage oocytes but the gonad of 14L:10D treatment group was still ripe phase with spermatozoa and mature stage oocyte. The $FSH{\beta}$ and $LH{\beta}$ mRNA expression in pituitary drastically decreased shot photoperiod treatment from July (spawning period). These results suggest that photoperiod is considered to be the most effective environmental factor in controlling the reproductive cycle of damselfish.

• The Korean Journal of Health Service Management
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• v.4 no.2
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• pp.23-31
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• 2010

This study analyzed whether the patients' visits to oriental medicine hospitals were influenced by the Euclidean distance from patients' residence to oriental medicine hospitals. Patient who visited two oriental medicine hospitals in a metropolitan area were selected for study sample. The number of patient from each Dong (which is the smallest administrative district) to two hospitals was calculated based on claims data in 2008. ArcGIS was used to calculate the distance. Distance variable was not statistically significant in regression analysis after controlling the difference of socio-economic status of people in each Dong. It seems that distance factor did not play an important role in deciding whether to use the services of oriental medicine hospitals in a metropolitan area.

• Journal of Energy Engineering
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• v.12 no.2
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• pp.101-108
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• 2003

The purpose of this study is to develop an entrainment model of the Pressurized Water Reactor (PWR) U-tube Steam Generator (SG) for Main Steam Line Break (MSLB) analyses. Generally, the temperature of the inside containment vessel at MSLB is decreased by introducing the liquid entrainment effect. This effect makes a profit on the aspect of integrity evaluation for Equipment Environmental Qualification (EEQ) in the containment. However, the target plant, Kori unit 1 does not have the entrainment data. Therefore, this study has been performed. RETRAN-3D and LOFTRAN computer programs are used for the model development. There are several parameters that are used for the initial benchmark, such as Combustion Engineerings (CE) experimental data and the RETRAN-3D model which describes the test leg. A sensitivity study is then performed with this model in which the model parameters are varied until the calculated results provide reasonable agreement with the measured results for the entire test set. Finally, a multiplication factor has been obtained from the 95/95 values of the calculated (best-estimate) quality data relative to the measured quality data. With this new methodology, an additional temperature margin of about 40$^{\circ}C$ can be obtained. So, the new methodology is found to have an explicit advantage to EQ analyses.

• Journal of Power System Engineering
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• v.18 no.5
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• pp.11-15
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• 2014

Currently, there are active researches being conducted on a new combustion technology that can reduce emission quantity while enhancing vehicle performance as well as Improving fuel quality. In a gasoline engine that uses petroleum, high volatility makes it easy to jump spark ignition and prevent knocking phenomenon that occurs inside an engine. In a diesel engine that uses diesel fuel, high volatility reduces combustion residues and toxic gas and is therefore good for protecting the environment. Therefore, for fuel used in a vehicle, volatility is an important factor that influences not only engine performance but also environmental protection. This research conducted a distillation experiment using gasoline and diesel fuel for vehicles produced by domestic oil companies. The test was conducted in accordance with the method of distillation experiment described in KS M ISO3405. In addition, it used the result of analysis from the experiment to examine visual distillation characteristics of each fuel and developed a formula based on distillation temperature.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.2
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• pp.83-89
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• 2005

This study aims to compare a self-reported and expert-observed method on ergonomic risk factors of Work-related Musculoskeletal Disorders (WMSDs). The checklist was developed based on the results of previous studies, and the symptoms of WMSDs were obtained using a self-reported questionnaire from 1,029 shipyard workers. The risk factors were assessed through the self-report by workers and video analysis by ergonomists. The symptom prevalence at the low back (59.2%), shoulders (50.8 %), and knees (49.7%) were relatively higher than those at other body parts. Odds ratios (ORs) by body parts were 2.48 to 2.90 for the risk job, and the ORs were significantly different from those of the low risk job. The risk factor scores by body parts between workers and ergonomist were very high correlation(r=0.82 to 0.92). The rates of self-report from risk job were 54.0% (elbow and arm) to 72.1 % (low back), but sometimes overestimated(105.7 to 122.6%) than those by ergonomists. The checklist, developed in this study, will be an efficient tool for the evaluation of risk jobs using self-report by workers.

• Computers and Concrete
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• v.26 no.5
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• pp.439-450
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• 2020

In this research, bending and buckling analyses of porous functionally graded (FG) plate under mechanical load are presented. The properties of the FG plate vary gradually across the thickness according to power-law and exponential functions. The material imperfection is considered to vary depending to a logarithmic function. The plate is modeled by a refined trigonometric shear deformation theory where the use of the shear correction factor is unnecessary. The governing equations of the FG plate are derived via virtual work principle and resolved via Navier solutions. The accuracy of the present model is checked by comparing the obtained results with those found in the literature. The various effects influencing the stresses, displacements and critical buckling loads of the plate are also examined and discussed in detail.

• BMB Reports
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• v.44 no.3
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• pp.211-216
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• 2011

Vitamin C (VC) is an important antioxidant and enzyme co-factor that works by stimulating the immune system and protecting against infections. It is well known that melanoma cells are more susceptible to VC than any other tumor cells. However, the role of VC in the treatment of colon cancer has not been studied. Cisplatin (CDDP) is a DNA damaging agent and is widely used for treating cancer, while the role of p53 in CDDP-induced cell death has been stressed. Using cell growth assays, morphological methods, Western blotting, flow cytometry, and DNA fragmentation analysis, we measured the expression of p53 level involved in the effect of VC on CDDP-induced apoptosis of HCT116, a human colon cancer cell line. CDDP plus VC treatment resulted in significantly increased apoptosis along with upregulation of p53 compared to untreated cells and/or CDDP-treated cells. These results suggest that VC enhanced CDDP sensitivity and apoptosis via upregulation of p53.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.3
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• pp.85-90
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• 1988

A probabilistic model for the failure in a homogeneous soil slope is presented. The Safety of the slope is measured through its probability of failure rather than the customary factor of safety. The safety margin of slope failure is assumed to follow a normal distribution. Sources of uncertainties affecting characterization of soil property in a homogeneous soil layer include inherent spatial variability., estimation error from insufficient samples, and measurement errors. Uncertainties of the shear strength-along potential failure surface are expressed by one-dimensional random field models. The rupture surface, created at toe of a soil slope, has been considered to propagate towards the boundary along a path following an exponential (log-spiral) law. Having derived the statistical characteristics of the rupture surface and of the forces which act along it, the probability of failure of the slope was found. Finally the developed procedure has been applied in a case study to yield the reliability of a soil slope.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1165-1171
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• 2013

The oversea construction contract amount has sharply increased since 2003. The contractor's capability for EPC and project management is a key factor for a successful industrial construction project. Construction performance measurement and evaluation is needed to improve contractor's project management capability. Therefore, this paper proposes the construction performance benchmarking program for oversea industrial projects. Performance metrics consists of project cost, schedule, quality, and safety. Data from 10 oversea industrial projects were collected and analyzed. Also, this paper describes the process for development of the benchmarking program and lessons learned from industry are summarized. Finally, this paper recommends how sustainable benchmarking program should be established and implemented.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.4
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• pp.197-203
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• 2020

This study investigates graduate competencies that can improve the uptake of higher education graduate outcomes in the working environment in Indonesia. This research was conducted by collecting data through sending questionnaires directly by the research team, via courier, or via postal service to respondents. A survey with questionnaire is carried out on April 2019, and the data from 117 respondents was analyzed. The sample population was all private higher education in the area of the I-XIV Higher Education Service Institution in Indonesia. This study employs factor analysis and structural equation modelling. The results show that the Graduates' competencies had a significant direct effect on the uptake of higher education graduates in the job market. The indirect effect of a Diploma Supplement and networking as mediation has a level of influence that is higher than the direct effect of graduate competence on the uptake of higher education graduate outcomes in the job market. The findings suggest that the Diploma Supplement and networking can increase the uptake of higher education graduates in Indonesia as expected by stakeholders and be able to compete in the global or international scale of environmental working. The professionalism of lecturers has a significant influence on the quality of learning.