• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.240-240
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• 2015

As Simpson et al. (1990) emphasized the importance of the straining process in the stratification and mixing in the estuarine circulation process, various researches have investigated on the relative contribution of each process to the overall potential energy anomaly dynamics. However, many numerical works have done only for two dimensional modeling along channel or the short distance cross sectional three dimensional simulations as Burchard et al. (2008) and the estuarine channel was not simulated so far. But, in the study on the physics of shallow coastal seas, spatial dimension in the three dimensional way affects significantly on results of a particular numerical model. Therefore, the comparison of two and three dimensional models is important to understand the real physics of mixing and stratification in an estuary. Also, as Geyer and MacCready (2013) pointed out that the lateral process seems to be important in determining the periodic stratifications, to study such process the three dimensional modeling must be required. The present study uses a numerical model to show the signification roles of each term of the time-dependent dynamic equation for the potential energy anomaly (PEA) in controlling along and lateral channel flows and different stratification structures. Moreover, we present the relationships between the ${\Phi}$-advection, the depth mean straining, vertical mixing and vertical advection can explain well how water level, salinity distribution and across velocity 2D model are slightly different from 3D.

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.1
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• pp.55-70
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• 2019

The phase properties of ground acceleration records from Mw 5.5~6.5 earthquakes are analyzed. The interrelationships between phase properties and significant durations, as well as PGA, are clarified through both of theoretical and empirical approaches. The probabilistic characteristics of phase information is also discussed based on previous studies and it is shown that circular normal distribution is the most appropriate probability distribution for the phase angle and phase difference. Whereas those variates can be modeled by Gaussian random variables. From the survey results on the frequency dependency of the phase statistics, a simple model is introduced, which is possible to express the frequency dependency of phase information. It is also shown that the significant duration can be controlled by appropriately chosen standard deviation of phase difference for 4~8Hz frequency band and additional consideration of phase scattering in higher frequency band through a series of Monte Carlo simulations. The source of phase scattering effect is also pointed out and discussed.

• Journal of Species Research
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• v.8 no.3
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• pp.259-267
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• 2019

Five free-living nematode species belonging to the order of Rhabditida are described for the first time in Korea. Two unrecorded species of Rhabditidae, Cruznema tripartitum (Linston, 1906) Zullini, 1982, and Poikilolaimus oxycerca de Man, 1895, and one species of Peloderidae, Pelodera strongyloides Schneider, 1860, were collected in Korea. C. tripartitum has nine pairs of genital papillae arranged in 2+2+1+4 differently from similar species of C. scarabaeum which has ten genital papillae arranged in 2+1+4+3. Poikilolaimus oxycerca has shorter tail (shorter than anal body diameter) compared to similar species of P. regenfussi which has longer tail(longer than anal body diameter). Pelodera strongyloides has shorter tail(1-1.5 times anal body diameters long) than P. punctata (4 anal body diameters long). Two unrecorded species of Panagrolaimidae, Panagrolaimus apicatus Schuurmans Stekhoven & Teunissen, 1938 and Panagrolaimus rigidus (Schneider, 1866) Thorne, 1937 were collected in Korea. P. apicatus has rounded and lower lip compared to similar species, P. margaretae Massey, 1964 which has finely pointed lip. P. rigidus has slender tail and lips rounded and flat barely separated when compared to similar species, P. subelongatus(Cobb, 1914) Thorne, 1937 which has plumper tail and lips are well separated.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.4
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• pp.532-548
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• 2019

This study examines Geumgwan Gaya's headgear, belt, and footwear. The relics excavated from tombs were examined first, then earthenware and clay figurines, followed by the visual data of related neighboring countries. The results are as follows. The headgear of Geumgwan Gaya, identified in the relics, is daegwan (帶輪式立飾冠) and lip (笠). Daegwan is a diadem with branch-shaped ornaments. It has an organic cap with fabric and leather as well as ties the strings to both ends of the diadem. Lip can be seen in the mounted figure of the earthenware. In neighboring countries, the top of lip is round or straight, but Geumgwan Gaya's lip is pointed and curved slightly backward. In addition, from neighboring countries' data, it is considered that the conical hat and gun (巾) are worn in Geumgwan Gaya. The belt is made of cloth or leather. Geumgwan Gaya also uses a belt with an animal-shaped hook and Jin style belt. Jin style belt shows the association with three-Yan culture of the Seonbi people in patterns and forms. Footwear of Geumgwan Gaya is li (履) and boots. Li included leather shoes, lacquer shoes, straw shoes and wooden shoes. In addition, there are leather boots decorated with round ornaments.

• Structural Engineering and Mechanics
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• v.78 no.5
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• pp.623-635
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• 2021

Previous studies have suggested the maximum experimental story shear force of beam-column joint frame does not reach its theoretical value due to beam-column joint failure when the column-to-beam moment capacity ratio was close to 1.0. It was also pointed out that under a certain amount of axial force, an axial collapse and a sudden decrease of lateral load-carrying capacity may occur at the joint. Although increasing joint transverse reinforcement could improve the lateral load-carrying capacity and axial load-carrying capacity of beam-column joint frame, the conditions considering varying axial force were still not well investigated. For this purpose, 7 full-scale specimens with no-axial force and 14 half-scale specimens with varying axial force are designed and subjected to static loading tests. Comparing the experimental results of the two types of specimens, it has indicated that introducing the varying axial force leads to a reduction of the required joint transverse reinforcement ratio which can avoid the beam-column joint failure. For specimens with varying axial force, to prevent beam-column joint failure and axial collapse, the lower limit of joint transverse reinforcement ratio is acquired when given a column-to-beam moment capacity ratio.

• Geomechanics and Engineering
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• v.24 no.3
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• pp.281-293
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• 2021

Uncertainties in geomechanical input parameters which mainly related to inappropriate data acquisition and estimation due to lack of sufficient calibration information, have led wellbore instability not yet to be fully understood or addressed. This paper demonstrates a workflow of employing Quantitative Risk Assessment technique, considering these uncertainties in terms of rock properties, pore pressure and in-situ stresses to makes it possible to survey not just the likelihood of accomplishing a desired level of wellbore stability at a specific mud pressure, but also the influence of the uncertainty in each input parameter on the wellbore stability. This probabilistic methodology in conjunction with Monte Carlo numerical modeling techniques was applied to a case study of a well. The response surfaces analysis provides a measure of the effects of uncertainties in each input parameter on the predicted mud pressure from three widely used failure criteria, thereby provides a key measurement for data acquisition in the future wells to reduce the uncertainty. The results pointed out that the mud pressure is tremendously sensitive to UCS and SHmax which emphasize the significance of reliable determinations of these two parameters for safe drilling. On the other hand, the predicted safe mud window from Mogi-Coulomb is the widest while the Hoek-Brown is the narrowest and comparing the anticipated collapse failures from the failure criteria and breakouts observations from caliper data, indicates that Hoek-Brown overestimate the minimum mud weight to avoid breakouts while Mogi-Coulomb criterion give better forecast according to real observations.

• Journal of Urban Science
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• v.11 no.1
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• pp.37-47
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• 2022

Even if Korea has established various legal guidelines as well as plans for the purpose of systematic management of urban citycapes, various problems have been pointed out, such as a decrease in operational efficiency because the legal framework is not clearly defined and the guidelines do not fully reflect regional characteristics. In the midst of this, Singapore is being mentioned as a representative example of enhancing international competitiveness by forming an outstanding urban cityscape through successful urban planning and operating system. Therefore, this study aims to suggest a direction for the improvement of Korea's urban planning and design guidelines by investigating and analyzing the characteristics of Singapore's urban planning system and design guidelines. As a result of the research and analysis, it was concluded that Singapore's urban planning system was based on the unified planning and management system. In particular, the Singapore Urban Design Guidelines provide differentiated guidelines to maintain and strengthen regional characteristics based on linkage with higher-level plans as detailed practical guidelines, and were operated as flexible guidelines reflecting the changes of the times and the needs of members of society. It also provides a direction for the improvement of the Korean urban design system, such as to increase the executionablity of the plan and the efficiency of operation by utilizing various guidance and support policies, rational and simplified deliberation procedures, and allow a platform that enhances the accessibility and convenience of related information.

• Health Policy and Management
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• v.33 no.4
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• pp.379-388
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• 2023

This study aims to propose the implementation of innovative payment models in Korea in order to promote the financial sustainability of the national health insurance system by reviewing the current status of the payment system in Korea and examining other countries' experiences with various innovative payment models. Korea primarily uses a fee-for-service payment system and additionally uses various payment systems such as case payment, per diem, and pay-for-performance. However, each payment system has its limitations. Many OECD (Organization for Economic Cooperation and Development) countries have pointed out the limitations of existing payment systems and have been attempting various innovative payment models (e.g., add-on payment, bundled payment, and population-based payment). Therefore, it is essential for Korea to consider innovative payment models, such as a mixed payment model that takes into account the strengths and weaknesses of each payment system, and to design and pilot these models. This process requires stakeholders to work together to build a social consensus on the implementation of innovative payment systems and to refine legal and systematic aspects, develop an integrated health information system, and establish dedicated organizations and committees. These efforts towards innovative payment models will contribute to developing a sustainable health insurance system that ensures the public's health and well-being in Korea.

• Asia pacific journal of information systems
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• v.32 no.3
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• pp.656-683
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• 2022

The COVID-19 pandemic has profoundly affected the world, inflicting nationwide lockdowns interrupting conventional schooling through schools, colleges and universities. Educational institutions are struggling to maintain learning continuity through remote learning solutions. Still, the students' perception of this 'new normal' mode and pace of learning needs to be examined to ensure the success of these efforts. This study aimed at examining the perception of higher education students in India and Croatia especially with respect to the association between cultural orientation and the e-learning. The period considered for the data collection was from March 2020 to September 2020. Correspondence analysis was attempted to create spatial maps to depict the respondent choices. Students from both the regions agreed to the high-power distance that existed in their cultures and considered the role of device and content to be an important dimension of e-learning for it to be effective, but the results also pointed out some differences in their choices on other culture dimensions as well as factors affecting e-learning which make this study unique and suggest in-depth future research for conclusive results.

• Journal of the Korean Dietetic Association
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• v.18 no.1
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• pp.43-58
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• 2012

This study was designed to investigate the impact of a 12-week nutrition education program on 32 male industrial workers (average age: $44.5{\pm}3.8$ yrs, work duration period: $20.1{\pm}5.6$ yrs) diagnosed as having dyslipidemia in a medical checkup at their workplace. This program was implemented with a conceptual framework on strengthening self-efficacy for the improvement of the health conditions of the workers. Most of all, the study exhibited benefits in the industrial workers by ameliorating the risk factors associated with dyslipidemia via changes in dietary behaviors, nutritional knowledge, and attitudes, as well as anthropometric and biochemical parameters. After the nutrition education, overall lifestyle, including the ratios of smoking (P<0.05) and drinking (P<0.01), significantly improved. Exactly 65.6% of the subjects reported that their dietary habits changed. Body weight, BMI, percentage of body fat, and waist circumference all significantly decreased (P<0.001). The systolic (P<0.01) as well as diastolic blood pressures (P<0.001) decreased. Moreover, the degree of increase in serum HDL-cholesterol was appreciable (P<0.001), and the atherogenic index also decreased (P<0.01). Further, risk factors related to metabolic syndrome in subjects significantly decreased (P<0.001). The average scores for nutrition knowledge increased from 9.3 to 17.7 points (P<0.001). All of the participants agreed on the need for a nutrition education program at their workplace. Further, it should be pointed out that the participants strongly indicated the need for continuing nutrition intervention.