• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.4
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• pp.364-375
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• 2020

Objectives: The purpose of this study is to suggest a direction for consumer-oriented curriculum development by analyzing the priorities of subjects and their preference for educational methods. Methods: The participants included 773 management supervisors and education practitioners in the workplace, and a survey was conducted from April 17 to August 30, 2019. Frequency analysis, t-test, Borich's Needs Analysis, and Locus for Focus Model analysis were performed using Microsoft Excel 2019 and IBM SPSS 21.0. Results: The highest perceived priorities for education subjects were as follows: ① 'CPR and First Aid Practice' and 'Occupational Disaster Prevention and First Aid Basics' in the manufacturing industry; and ② 'Emotional Labor and Job Stress Prevention', 'Occupational Disaster Prevention and First Aid basics, and 'Musculoskeletal Disorder Prevention' in the service industry. 'Collective education' was the most preferred method of education. 'School-type' was preferred for the seating arrangement, and the proper number of trainees was considered to be about 30. Respondents said the contents of the education was a top priority when they applied for education, and curriculum and appropriate textbooks should be considered in calculating the cost of education. Conclusions: Practical subjects and subjects related to major hazards by industry were required for management supervisor education. It was proposed in this study that the contents and operating methods of education be changed so that workers can easily comprehend essential subjects such as the Occupational Safety and Health Act. In conclusion, it is necessary to design the curriculum and apply educational methods suitable for each subject's characteristics in consideration of the priorities for subjects reflected in the needs of trainees.

• Steel and Composite Structures
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• v.39 no.5
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• pp.631-643
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• 2021

The aim of this work is to study the hygro-thermo-mechanical bending responses of simply supported FG plate resting on a Winkler-Pasternak elastic foundation. The effect transverse shear strains is taken into account in which the zero transverse shear stress condition on the top and bottom surfaces of the plate is ensured without using any shear correction factors. The developed model contains only four unknowns variable which is reduced compared to other HSDTs models. The material properties of FG-plate are supposed to vary across the thickness of the plate according to power-law mixture. The differential governing equations are derived based on the virtual working principle. Numerical outcomes of bending analysis of FG plates under hygro-thermo-mechanical loads are performed and compared with those available in the literature. The effects of the temperature, moisture concentration, elastic foundation parameters, shear deformation, geometrical parameters, and power-law-index on the dimensionless deflections, axial and transverse shear stresses of the FG-plate are presented and discussed.

• The Journal of Internal Korean Medicine
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• v.42 no.2
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• pp.175-183
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• 2021

Diabetes mellitus, commonly known as diabetes, comprises a group of metabolic disorders characterized by a high blood sugar level over a prolonged period of time. Diabetes is classified into type 1 diabetes and type 2 diabetes, and the incidence and prevalence of diabetes, mostly type 2, have increased remarkably in recent decades. A diagnosis of type 2 diabetes is greatly influenced by heredity, and it is important to prevent diabetes in people with a family history by improving lifestyle and environmental factors. Controlling overeating, obesity, lack of exercise, and stress is effective to prevent diabetes. The patient in this case report had impaired fasting glucose and mild hyperlipidemia. The patient experienced improvements in these sequelae after the administration of herbal medicine (Yangkyuksanwha-tang) for 12 weeks and the implementation of a plant-based diet. The complete blood count, XXXX, fasting blood sugar, HbA1c, insulin, and C-peptide levels were measured, and the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and HOMA-β were calculated according to the FBS and fasting insulin levels. Total cholesterol, triglyceride, FBS, and HbA1c levels all decreased after 12 weeks compared with baseline measures. There was no change in the insulin secretory ability; the C-peptide level did not change as a result of β-cell function; and the HOMA-β level reflected an improved insulin secretory ability.

• Korean journal of aerospace and environmental medicine
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• v.30 no.3
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• pp.83-85
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• 2020

In commemoration of Vol. 30, Issue 3, our journal prepared five review articles and one original paper. The global outbreak of COVID-19 in 2020 has impacted our society, and especially the aviation and travel industries have been severely damaged. Kwon presented the aviation medical examination regulations related to COVID-19 announced by the Ministry of Land, Infrastructure, and Transport of the Republic of Korea. Lim summarized various efforts of airlines to overcome the crisis in the aviation industry. He also discussed the management of these aircraft as the number of airplanes landing for long periods increased. Finally, he suggested various quarantine guidelines at airports and onboard aircraft. COVID-19 has had a profound impact on mental health as well as physical effects. Kim investigated the impact of COVID-19 on mental health and suggested ways to manage the stress caused by it. The Internet of Things (IoT) refers to a technology in which devices communicate with each other through wired or wireless communication. Hyun explained the current state of the technology of the IoT and how it could be used, especially in the aviation field. In the area of airline service, various situations arise between passengers and crew. Therefore, role-playing is useful in performing education to prepare and respond to passengers' different needs appropriately. Ra introduced the conceptual background and general concepts of role-playing and presented the actual role-play's preparation process, implementation, evaluation, and feedback process. For a fighter to fly for a long time and perform a rapid air attack, air refueling is essential, which serves refueling from the air rather than from the aircraft base. Koo developed a questionnaire based on the HFACS (Human Factors Analysis and Classification System) model and used it to conduct a fighter pilot survey and analyze the results.

• Journal of the Korean Geotechnical Society
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• v.24 no.10
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• pp.25-32
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• 2008

Based on recent studies, the side resistance of rock socketed drilled shafts was affected by unconfined compressive strength of rock, socket roughness, rock types and joints, and initial normal stress. Especially, the socket roughness was affected by rock types and joints, drilling methods, and diameters of pile. In this study, a new roughness measurement system (BKS-LRPS, Backyoung-KyungSung Laser Roughness Profiling System) usable in water was developed. Based on the laboratory model tests, an EMD (Effective Measurement Distances) according to various turbidity was proposed as $EMD=1149.2{\times}T_{b}^{-0.64}$.

• Journal of the Korean Geotechnical Society
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• v.23 no.8
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• pp.69-76
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• 2007

Axial behavior of tapered piles is affected by taper angle, stress state of soils, soil frictional angle and pile-soil interface friction angle. In this paper, a series of model pile load tests were performed using a calibration chamber in order to investigate the effect of taper angle on the axial response of cast-in-place tapered piles in sand. According to results of the tests, as taper angle of piles increased, the shaft load capacity of piles increased but its base load capacity decreased. The unit base load capacity of piles increased with increasing taper angle for medium sand but decreased for dense sand. The ratio of shaft to total load capacity increased with increasing taper angle and with decreasing relative density of soils. The test results also showed that total load capacity per unit pile volume increased with increasing taper angle for medium sand, but it decreased for dense sand. Therefore, it can be stated that tapered piles are economically more beneficial for medium sand than for dense sand.

• Coupled systems mechanics
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• v.12 no.3
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• pp.199-220
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• 2023

This article presents a new analytical model to study the effect of porosity on the shear correction factors (SCFs) of functionally graded porous beams (FGPB). For this analysis, uneven and logarithmic-uneven porosity functions are adopted to be distributed through the thickness of the FGP beams. Critical to the application of this theory is a determination of the correction factor, which appears as a coefficient in the expression for the transverse shear stress resultant; to compensate for the assumption that the shear strain is uniform through the depth of the cross-section. Using the energy equivalence principle, a general expression is derived from the static SCFs in FGPB. The resulting expression is consistent with the variationally derived results of Reissner's analysis when the latter are reduced from the two-dimensional case (plate) to the one-dimensional one (beam). A convenient algebraic form of the solution is presented and new study cases are given to illustrate the applicability of the present formulation. Numerical results are presented to illustrate the effect of the porosity distribution on the (SCFs) for various FGPBs. Further, the law of changing the mechanical properties of FG beams without porosity and the SCFare numerically validated by comparison with some available results.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4A
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• pp.611-622
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• 2008

Nonlinear analyses have been carried out for both bridge piers and a bridge structure being repaired using a repair element in order to assess the post-repair seismic response of such structures. For this purpose, a simplified CFRP stress-strain model has been proposed. The analytical predictions incorporating the current developments correlate reasonably well with experimental results in terms of strength and stiffness. In addition, nonlinear dynamaic analyses have also been conducted for a bridge structure in terms of the created multiple earthquake sets to evaluate the effect of pier repair on the response of a whole bridge structure. In these analyses, potential plastic hinge zones of piers are virtually repaired by CFRP and steel jacketing. Comparative results prove the virtual necessity of performing nonlinear post-repair analyses under multiple earthquakes, particularly when the post-repair response features are required. In all, the present approaches are expected to provide salient information regarding a healthy seismic repair intervention of a damaged strcuture.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3A
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• pp.523-532
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• 2006

It is thought that the suggestion of efficient and rational design guideline based on the behavior evaluation of bridge structure system the included cross beam is necessary for the construction efficiency of two-I girder steel bridges. Therefore, in this study, the effects of influence parameters are investigated by the behavior analyses of the bridges, in which the influence parameters are location, spacing and rigidity of the cross beam. For this study, the existed two-I girder steel bridges firstly were selected with the model of case study and the FE analyses for some case models were performed to estimate the action of the cross beam in the bridge. From the analyses, it was estimated that if it consider local stress and load distribution of a floor system, shell and solid elements are compatible to modeling of the cross beams. Also, the efficient design guideline for the cross beam of two-I girder steel bridge was suggested from parameter studies used location, spacing and rigidity of the cross beam.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4C
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• pp.137-144
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• 2009

In this research, the ground with smeared zone was reconstructed using the large consolidation test apparatus. And the reconstituted kaolinite samples at different locations were retrieved for the oedometer test. From the oedometer test results the permeability- void ratio-effective stress behavior was investigated. Based on the experimental analysis, spatial differences of permeability according to the drainage distance by both smear and radial drainage consolidation reduced as the consolidation proceeds and eventually disappeared in normally consolidated region. And the spatial variation of permeability by radial drainage consolidation showed larger differences in smaller extent than the spatial variation of permeability by smear.