• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.407-410
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• 2000

In the using of FBG developed in home land, We designed and manufactured three types of FBG sound transducers the first in Korea. Analysizing special character's on FBG transducers manufactured, we made an experiment on respective frequency peculiarities in the water and we made an experiment on multi-point signal detection and direction about optional acoustic underwater. As the experimental result, we made it possible acoustic detection on frequency peculiarities to maximum 18k0z and made certain the system arrary possibilities, from now on we prepared the practical use study possibilities.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.3
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• pp.625-631
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• 2013

Two-phase pressure drop experiments were performed during flow boiling to deionized water in a microchannel having a hydraulic diameter of $500{\mu}m$. Tests were made in the ranges of heat fluxes from 100 to $400kW/m^2$, vapor qualities from 0 to 0.2 and mass fluxes of 200, 400 and $600kg/m^2s$. The frictional pressure drop during flow boiling is predicted by using two models; the homogeneous model that assumes equal phase velocity and the separate flow model that allows a slip velocity between two phases. From the experimental results, it is found that the two phase multiplier decreases with an increase in mass flux. Measured data of pressure drop are compared to a few available correlations proposed for macroscale and mini/microscale. Among the separated flow models, the correlation model suggested by Lee and Garimella predicted the frictional pressure drop within MAE of 47.2%, which is better than other correlations.

• Journal of the Korean Institute of Educational Facilities
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• v.23 no.2
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• pp.19-29
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• 2016

In the context of lifelong education program for an aging society and information age, elementary school facilities are expected to accommodate various people in diverse age group and diverse physical abilities. Introduction of the 'Universal Design' concept seems inevitable in school environment in terms of public infra structure for community. However, in architectural point of view, unlike foreign examples, simply applied barrier-free and safety standards of domestic guidelines based on dimensional data does not function enough to achieve universal design in authentic manner. This study is focused on this issue and suggests the direction of improvement for architectural design guidelines. Through the comparative analysis of foreign and domestic design guidelines, two principles of universal design-'Flexibility in Use', 'Perceptile Information'- are found to be lacking in the domestic design guidelines for elementary school facilities. It is expected for government authority to develop more concrete guidelines to achieve universal design for school as a basic public space in the community.

• Journal of Korean Society on Water Environment
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• v.35 no.6
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• pp.520-538
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• 2019

In this study, it was proposed that a method of setting the target water quality for TOC using the watershed model and the load duration curves to manage non-biodegradable organics in the total water load management system. To simulate runoff and water quality of the watershed, the HSPF model is used which is appropriate for urban and rural areas. Additionally, the load duration curve is used to reflect the variable water quality correlated with various river flow rates in preparing the TMDL plans in the U.S. First, the model was constructed by inputting the loads calculated from the pollutant sources in 2015. After the calibration and verification process, the water quality by flow conditions was analyzed from the BOD and TOC simulation results. When the BOD achieved the target water quality by inputting the target year loads for 2020, the median and average values of TOC were proposed for the target water quality. The provisional method of TOC target water quality for the management of non-biodegradable organics, which is one of the challenges of the total water load management system, was considered. In the future, it is expected to be used as basic data for the conversion of BOD into TOC in the total water load management system.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.3
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• pp.325-331
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• 2018

This paper deals with the dynamical analysis of a vessel that leads to capsize in regular beam seas. The complete investigation of nonlinear behaviors includes sub-harmonic motion, bifurcation, and chaos under variations of control parameters. The vessel rolling motions can exhibit various undesirable nonlinear phenomena. We have employed a linear-plus-cubic type damping term (LPCD) in a nonlinear rolling equation. Using the fourth order Runge-Kutta algorithm with the phase portraits, various dynamical behaviors (limit cycles, bifurcations, and chaos) are presented in beam seas. On increasing the value of control parameter ${\Omega}$, chaotic behavior interspersed with intermittent periodic windows are clearly observed in the numerical simulations. The chaotic region is widely spread according to system parameter ${\Omega}$ in the range of 0.1 to 0.9. When the value of the control parameter is increased beyond the chaotic region, periodic solutions are dominant in the range of frequency ratio ${\Omega}=1.01{\sim}1.6$. In addition, one more important feature is that different types of stable harmonic motions such as periodicity of 2T, 3T, 4T and 5T exist in the range of ${\Omega}=0.34{\sim}0.83$.

• The Journal of the Convergence on Culture Technology
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• v.4 no.2
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• pp.9-16
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• 2018

This study focuses on investigate to the Special Tax of the Seaway Traffic Certificate collected by Tongjeyoung for secure of Gunyangmi and safety of the people and military recruitment for the navy rebuilding carried out by Yi Soon-sin of Jeongyujaeran period. In addition, I examined Yu-Hyeng, Lee Eui-On, Choi Hee-Ryang, and Jung Sa-Joon's brothers who played a major role in helping Yi Soon-sin and rebuilding the navy. Yi Soon-sin is the person to be sown forever as the Holy Hero of the save country that saved Chosun from the aggression of the Japen enemy. In addition to these contents, this study has significance in focusing on the part where Yi Soon-shin went beyond the top commander of the navy army organization and exerted his ability as the administrator for the nation and the people.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.9
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• pp.455-462
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• 2017

The purpose of this study is to analyze heating and cooling load variation due to envelope retrofits in an old school building. In a previous study, envelope retrofit of an old school building resulted in annual energy consumption reduction. However, cooling energy consumption increased with the envelope retrofit. This is because of high internal heat generation rates in school buildings and internal heat cannot escape through windows or walls when the envelope's thermal performance improves. To clarify this assumption, thermal performance changes due to envelope retrofits were analyzed by simulation. Results revealed indoor temperature and inner window surface temperature increased with high insulation level of windows. Indoor heat loss through windows by conduction, convection and radiation decreased and resulted in an increase of cooling load in an old school building. From results of this study, energy saving impact of envelope retrofits in an old school building may not be significant because of high internal heat gain level in school buildings. In case of replacing windows in school buildings, local climate and internal heat gain level should be considered.

• The Journal of Fisheries Business Administration
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• v.46 no.2
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• pp.43-57
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• 2015

The study aims to identify the current status of aquaculture information in Korea and suggests policy directions for its integrated management. Firstly, the study focuses on the identification of the current status of aquaculture information by reviewing how aquaculture information is managed. Secondly, this study identifies problems such as lacks in necessary aquaculture information, inefficiency caused by dispersion and overlapping of information, absence of integrated management system and insufficient sharing of information. After identifying the current status of aquaculture information and its problems, the study suggests three basic directions to systematically integrate and manage the information such as establishment of infrastructure for promoting the integrated management of aquaculture information, generation and systematic management of useful aquaculture information and enhancement of user convenience. Finally, the study suggests detailed strategies such as establishment of a foundation to facilitate integrated management of aquaculture information, organization of organic network, sharing of more information, creation of necessary information through demand survey, creation of systematic management system, provision of a customized total service, and increase in education and PR activities on information use.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.3
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• pp.269-282
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• 2019

The purpose of this study is to investigate the relationship between the spectator experience and satisfaction with a focus on attachment and a sense of community. The survey was given to random spectators who watched KBO (The Korea Baseball Organization) games in 2018. With 189 surveyed participants, this study used exploratory factor analysis and reliability analysis to verify the reliability and validity of the measured variables. The hierarchical multiple regression correlation was employed as a statistical method for the hypotheses of this study. The findings showed that spectators' experiences have influences on satisfaction. Among the experience factors, education and entertainment affect attachment, and education has the only significant influence on a sense of community. In addition, spectators' attachment and a sense of community positively influence satisfaction. Attachment and a sense of community have a relatively mediated effect on spectators' experiences and satisfaction. This study confirmed the need for various spectator experiences at KBO games, and the importance of place attachment or a sense of community.

• International Journal of Advanced Culture Technology
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• v.8 no.1
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• pp.226-235
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• 2020

In this paper, we present to evaluate physiological activity of Robinia pseudo-acacia leaf and its skin penetration using liposome and cell penetrating peptide. After extraction with Robinia pseudo-acacia leaf using the distilled water and supercritical, various physiological activities were examined. In antioxidants experiments, the total concentration of polyphenol compounds was determined to be 56.88 mg/g in hydrothermal extract, 45.07 mg/g in supercritical extract. The DPPH radical scavenging ability at 1,000 ㎍/mL was 33.97% in supercritical extract. The scavenging effect on SOD experiment at 500 ㎍/mL was 76.41% in supercritical extract. In the antimicrobial experiments, the hydrothermal extract had no effect, but supercritical extract represented maximum clear zone of 14.00 mm in Staphylococcus aureus strain. Liposome containing the RSE (Robinia pseudo-acacia leaf supercritical extract) reduced particle size and stabilized zeta potential. In the epidermal permeability experiment, it was confirmed that the permeation of liposome containing the RSE and cell penetrating peptides was remarkable.