• Journal of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.86-97
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• 1993

A numerical method is developed for the nonlinear motion of two-dimensional wedges and axisymmetric-forced-heaving motion using Semi-Largrangian scheme under assumption of potential flows. In two-dimensional-problem Cauchy's integral theorem is applied to calculate the complex potential and its time derivative along boundary. In three-dimensional-problem Rankine ring sources are used in a Green's theorem boundary integral formulation to salve the field equation. The solution is stepped forward numerically in time by integrating the exact kinematic and dynamic free-surface boundary condition. Numerical computations are made for the entry of a wedge with a constant velocity and for the forced harmonic heaving motion from rest. The problem of the entry of wedge compared with the calculated results of Champan[4] and Kim[11]. By Fourier transform of forces in time domain, added mass coefficient, damping coefficient, second harmonic forces are obtained and compared with Yamashita's experiment[5].

• Journal of Korea Water Resources Association
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• v.37 no.10
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• pp.823-836
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• 2004

Using the simple geometry for the idealized catchment consisting of two plane surfaces and a stream between them, runoff was analysed for the moving storms based on the kinematic wave equation. The storm velocity applied in this study was 0.25∼2.0 m/s moving up, down and cross direction of catchment. Applied rainfall distribution types are uniform, advanced, delayed, intermediate type. The results indicate that the moving storms of cross direction generate the largest peak runoff, and the smallest runoff appears in the case of up stream direction. The sensitivity of runoff to rainfall distribution types decreases as storm velocity increases. It is clear that faster storm velocity generates faster peak time and becomes thin hydrographs rapidly.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.363-366
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• 2005

Social survey and auditory experiment on residential noises such as floor impact, air-bome, bathroom, drainage and traffic noises were conducted to investigate the effects of sensitivity and background noise levels on subjective response to residential noises. Results of survey showed that multiple questions for sensitivity to noise have a more power for discrimination against subjective response to noise than single question. It was also found that the correlation between sensitivity and annoyance was relatively low, but the differences in annoyance between sensitivity groups were significant. Result of auditory experiment showed that effects of sensitivity on annoyance were different according to noise type and noise level. It was also shown that the difference in annoyance between the lowest sensitive stoup and the highest sensitive group was significant in low noise level. The effects of background noise on subjective responses to noise was also different according to noise source and noise level, and were significant in low noise level of airborne and drainage noise.

• Korean Journal of Hazardous Materials
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• v.6 no.2
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• pp.30-38
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• 2018

This study analyzed the gender factors and priorities that are on the basis for establishing the school safety education policy according to the times when the demand for customized education is increasing. AHP analysis method was used in the paper for systematic and hierarchical analysis. We had checked a safety education specialist group to identify the priorities of important factors to improve the efficiency of analysis. The male group first considered the change of the beneficiary by policy guidelines, and the female group regarded the change of interest and public opinion as important. This has studied the difference in approach between the two groups, although the key elements of the detailed policy are the same. This study suggests that school safety education is effective in improving effective gender safety education response capacity and ensuring substantive policy sustainability.

• Journal of Korea Society of Industrial Information Systems
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• v.26 no.1
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• pp.11-19
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• 2021

The emerging Fifth Generation (5G) network technology brings us a new demand for low latency services. However, it may not be possible for long-distanced cloud computing servers to support users with satisfactory low latency services. For this reason, Multi-access Edge Computing (MEC) technology are gaining attraction since it is designed to provide low latency services to users by placing cloud computing resources to base-stations or mobile switching centers nearby users. Accordingly, it is necessary to verify the deployed containers on the MECs are reliable enough to provide low latency services empirically. For the purpose, we develop a testing tool to verify the reliability as well as network resources status of running MECs by deploying containers on the MECs in a Kubernetes environment.

• Journal of the Korean Chemical Society
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• v.37 no.2
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• pp.183-190
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• 1993

The properties of oxidation reactions of carbon monoxide on ZnO (1010) were studied at the temperature range of 298∼573 K by measuring the capacitance and conductance in the insulating layer of two contacting crystal faces which vary with ZnO-gas interaction mechanisms. Exposure of the sample to CO resulted in an increase in the layer depth at 298∼373 K, while it decreased above 473 K. But the variation of the layer depth was very small in all measurements. When CO was admitted to the sample previously treated with $O_2$ at the same temperature, we observed the different features compared with the case of CO adsorption. From these results we discussed the mechanisms of CO oxidation in connection with the adsorbed oxygen species at each temperature.

• Journal of Yeungnam Medical Science
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• v.4 no.2
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• pp.23-27
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• 1987

Mass electrocardiographic (ECG) examination was performed on 13,801 children (male 7,526 and female 6,275) of elementary and middle school in Taegu from May 1. 1986. to April 30. 1987. We read their ECG according to the "Pediatric Electrocardiography." The results were as following; The Incidence of ECG abnormality was 1.05%(male 1.3% and female 0.75%). Fifty eight children (0.42%) had atrial and ventricular hypertrophy; two right atrial hypertrophy, five left atrial hypertrophy, thirty five fight ventricular hypertrophy and sixteen left ventricular hypertrophy respectively. Ectopic beats occurred in 25 children (0.18%) ; They were atrial in 12 children, ventricular in 8 children and junctional in 5 children. There were 62 children (0.45%) of conduction disturbance ; They were first degree atrioventricular (A-V) block in 21 children, type I second degree A-V block in 1 child, A-V dissociation in 1 child, right bundle branch block in 36 children, left bundle branch block in 1 child and WPW syndrome in 2 children. Nonspecific ST, T changes and sinus tachycardia were found in 3 and one children respectively.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.65-75
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• 2020

This study is a convergence study of 596 high school girls in order to confirm the relationship between the desired number of meat side dishes and preference of fish side dishes in school meals. Data were analyzed by χ²-test, ANOVA-test, and Duncan's test using SPSS 22.0 program. The results of the study were as follows. The scores of the subjects for promoting palatability were highest in the items 'Easy to eat' and 'Without fishy'. The scores of 'Nutrition Education', 'Combined with Preferred Food', 'Without Fishy' and 'Add Preferred Flavor' tended to increase significantly as the desired frequency of meat side dishes increased from 'less than three times a month' to 'more than five times a week'. The findings of the study confirmed the relationship between the desired frequency of meat side dishes and preference of fish side dishes. Therefore, this study is expected to provide high school girls with a way to increase fish preference.

• Journal of Korea Game Society
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• v.16 no.6
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• pp.131-142
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• 2016

Recently, a variety of methodologies based on the use of educational coding robots have been proposed and experimented in newly emerging korean educational coding markets. Due to imprecise movement accuracy of the existing coding robots, however, such robots are mainly used as a toy. Inspired by these observations, we developed a simple adjustment method during robot movements, which is based on the observation results of 6 line-tracking sensors: 3 sensors in the center of a robot and other 3 sensors at the front. These sensors help to determine whether the robot is in the right location and whether it rotates as expected. Through the well-designed experiments, we report the effectiveness of our proposed solution: the average distance error of 1.57cm and the average degree error of 2.38 degree before and after complex movements. In near future, we hope our method to be popularly used in various educational coding robot platforms.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.10a
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• pp.4-4
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• 2010

식물자원은 예로부터 인류의 생활과 긴밀한 관계를 유지하면서 인류에게 삶의 터전을 제공하였으며 쾌적한 환경을 유지시켜 주는 기반이 되었음은 물론 인류의 생존을 위한 많은 재화를 공급하여 왔다. 이러한 식물자원의 가치는 인간생활의 기초적 의 식 주 뿐 만 아니라 질병치료를 위한 재료로도 활용되고 있다. 제주도는 지리적으로 아열대권 생물자원의 확보 및 관리가 용이한 위치에 있어 아열대 자원 및 동북아섬 자원의 보존과 활용을 위한 전진기지로서 최적지이며, 난대, 온대, 한대 및 아고산대에 걸쳐 2,100여종의 식물자원이 분포하는 생태계 보고로 알려져 있다. 특히, 진시황이 불로초를 찾아 신하를 보낸 곳이 제주도라고 전해지고 있는 만큼 이는 제주가 많은 자원식물이 분포하고 있음이 그 옛날에도 알려져 있었다는 증거라 할 수 있다. 제주에 분포하거나 재배되는 식물 중 약용 및 식용 식물자원으로 잠재적 가치를 갖고 있는 식물은 550여 분류군으로서, 양치식물 43종류, 나자식물 6종류, 단자엽식물 31종류, 쌍자엽식물 370종류 등이다. 이러한 자원식물 중 상록성 목본 31종류, 낙엽수 105종류, 만경류가 51종류, 초본류(1년초 또는 다년초)가 358종류이며, 뱀톱, 천남성, 박새 등 독성을 가지는 식물도 43종류가 포함되어 있다. 비록 기존 알려진 약용 및 식용 식물자원이 산업적 중요성을 가지고 있다고는 하나 그 약효나 효능의 검정이 제대로 이루어지고 있지 않은 나머지 자생식물까지 포함하면 상당수의 제주 자생식물이 자원식물로 사용될 수 있는 잠재적 가치를 가지고 있다고 할 수 있다. 최근 생활수준의 향상으로 삶의 질과 건강에 대한 관심이 집중하고 있으며, 자원식물 유래 천연물을 소재로 한 향장품 및 건강기능성 식 의약품을 포함한 기능성 상품은 안전성이 보장되며 우수한 생리활성이 있는 것으로 밝혀지면서, 자원식물을 소재로 한 기능성 상품의 개발에 대한 수요가 증가하고 있는 실정이다. 제주지역도 청정지역 제주에 자생하고 있는 자원식물의 잠재적 가치를 활용하여 미래 제주 창출을 위한 신산업육성을 위한 노력을 기울이고 있다. 특히, 제주 자원식물들의 잠재적 가치를 활용하여 부가가치를 높이기 위해 건강 뷰티 생물산업을 지역전략산업으로 추진하면서 제주 자원식물들의 새로운 잠재적 가치를 조명하고 있어 이에 대한 지역내 추진노력 및 관련 산업현황 등을 정리하여 몇가지 견해를 제기하고자 한다.