• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.7
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• pp.693-700
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• 2016

It is important that we can calculate the order of non-supersingular elliptic curves with large prime factors over the finite field GF(q) to guarantee the security of public key cryptosystems based on discrete logarithm problem(DLP). Schoof algorithm, however, which is used to calculate the order of the non-supersingular elliptic curves currently is so complicated that many papers are appeared recently to update the algorithm. To avoid Schoof algorithm, in this paper, we propose an algorithm to calculate orders of elliptic curves over finite composite fields of the forms $GF(2^m)=GF(2^{rs})=GF((2^r)^s)$ using Weil's theorem. Implementing the program based on the proposed algorithm, we find a efficient non-supersingular elliptic curve over the finite composite field $GF(2^5)^{31})$ of the order larger than $10^{40}$ with prime factor larger than $10^{40}$ using the elliptic curve $E(GF(2^5))$ of the order 36.

• Proceedings of the Korean Society for the Gifted Conference
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• 2003.11a
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• pp.165-166
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• 2003

2002년 3월부터 영재교육법 시행령이 적용됨에 따라 과학기술부에서는 교육인적자원부, 부산광역시 교육청과의 협약을 통하여 부산과학고등학교를 과학영재학교로 지정하였으며 2003년 3월 신입생 입학 이후 현재까지 운영되고 있다. 과학영재를 조기에 발굴하여 맞춤식 교육을 체계적으로 실천함으로써 지식기반 사회를 선도할 수 있는 창의적인 과학영재를 육성하려는 과학영재학교의 설립목적에 부합되도록 계획, 운영, 평가되기 위해서 현재 진행되고 있는 운영 전반에 대하여 점검 및 분석이 이루어질 필요가 있다. 이에 과학영재학교 운영상의 주요 측면인 교육과정 운영 분야에 대하여 그 실태와 학생 반응을 분석하는데 본 연구의 목적이 있다. 과학영재학교의 교육과정 기본 방침은 과학 분야에 대한 깊은 이해와 논리적, 비판적, 창의적 사고력과 태도를 통하여 지식을 창출하는 자기 주도적 탐구자의 양성을 전제로 하고 있으며 교육과정 편제는 교과, 자율연구, 위탁교육 및 특별활동으로 구성되어있다. 교과에는 국어, 사회, 외국어, 예체능을 포함하는 보통교과와 수학, 과학, 정보과학을 포함하는 전공교과가 있다(과학영재학교 교수요목안내서, 2003). 본 연구에서 교육과정 편제, R&E, 교수학습 및 평가의 하위 영역별로 그 실태와 각 영역별 학생 설문 결과를 분석한 결과는 다음과 같다. 첫째, 영재학교 교육과정 편제 및 운영에 대한 학생들의 인식을 조사한 결과, 심화 선택과목의 학점 비중을 더 높여야한다는 의견과 보통교과의 학점을 줄이고 전공교과의 학점을 늘려야 한다는 의견이 상대적으로 높게 나타났다. 이러한 결과는 대상 학생들이 과학영재학교 선발과정에서 수학, 과학 각 분야별 우수자로 선발된 경우가 많아 학생 개인적으로 자신감을 가지는 과목만 집중적으로 학습하고자 하는 의도의 반영으로 볼 수 있다. 이와 관련하여 영재교육과정의 운영지침(이상천, 2002)에 의하면, 대학 수준의 내용을 그대로 도입하는 속진보다 창의성과 사고력 계발에 보다 충실할 수 있도록 내용의 폭을 넓히고 접근방법을 달리하는 심화 중심으로 교육과정을 구성하고 운영한다고 하였다. 그러나 현재 개발된 교육과정 편성과 운영은 창의성 교육의 구현보다는 압축형 속진 교육과정의 특성이 강하여, 이와 같은 운영지침을 실현하기 어려운 것이 현실이므로 교육과정 편제의 개선이나 운영지침에 적합한 교육내용의 개발이 시급히 이루어져야 할 것이다. 둘째, R&E(Research ＆ Education)는‘연구를 통한 교육’,‘교육을 통한 연구’를 의미하며 과학영재교육과정의 가장 큰 특징이라 할 수 있는 자율연구와 위탁교육을 위한 프로그램이다.

• Journal of Yeungnam Medical Science
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• v.24 no.2
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• pp.148-153
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• 2007

Background : Computer- and web-based simulation methods help students develop problem solving and decision making skills. In addition, they provide reality based learning to the student clinical experience with immediate medical feedback as well as repetitive training, on-site reviews and case closure. Materials and Methods : Seventy-five third-year medical students participated in a two-week simulation program. The students selected four modules from eight modules as follows: airway and breathing 1, cardiac arrest 1, cardiac arrhythmia 1, and chest pain 1, and then selected the first case within each of the modules. After 2 weeks, a pass score was obtained and the data analyzed. The average pass score of over 70% was considered a passing grade for each module. If the student did not pass each module, there was no score (i.e., pass score was zero). In addition, when at least one of the four modules was zero, the student was not included in this study. Results : Seventy-five students participated in the simulation program. Nineteen students were excluded based on their performance. The final number of students studied was 56 students (74.7%). The average scores for each module 1 to 4 were 86.7%, 85.3%, 84.0%, and 84.0%, and the average obtained pass score was 88.6 for the four modules in all 56 students. Conclusion : Medical simulation enabled students to experience realistic patient situations as part of medical learning. However, it has not been incorporated into traditional educational methodology. Here we describe the introduction and the development of various simulation modules and technologies for medical education.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.194-202
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• 2019

This study examined the emotional intelligence and social support in relation to resilience in order to identify the factors influencing resilience in student nurses. The participants were 228 student nurses from two colleges in B City. The data were analyzed using a t-test, ANOVA, Pearson correlation coefficient, Scheffe test and multiple regression analysis by SPSS ver. 21.0. The mean score for emotional intelligence, social support, and resilience level was 5.36 out of 7 points, 4.13 out of 5 point, and 2.68 out of 4 points, respectively. Resilience was positively correlated with emotional intelligence (r=.665, p<.001) and social support (r=.495, p<.001). The results of this research suggest that social support is an important variable affecting resilience in student nurses. The factors affecting resilience were social support (${\beta}=.464$, p<.001), emotional intelligence (${\beta}=.169$, p=.004), and aptitude (${\beta}=.162$, p=.006). Resilience explained 50.4% of the variance in social support, emotional support, and aptitude. To increase the resilience of student nurses, managers need to develop resilience programs and training for managing social support, emotional intelligence, and aptitude.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.669-676
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• 2020

The purpose of this study was to analyze the changes in the values of Hounsfield Unit (HU) according to the changes in monoenergy (keV) and dilution ratio of the contrast agent, using the spectral CT. Spectral CT was used as the testing device, while 20 cc syringe phantom was used to set a total of six dilution ratios of the contrast agent: 8:2, 7:3, 6:4, 5:5, 4:6, and 3:7. Here, the non-ionic iodine solution (350 mg/ml) was used as a contrast agent. The syringe axial image was reconstructed by adjusting the obtained data on nine MonoE levels; 40 keV, 45 keV, 50 keV, 55 keV, 60 keV, 65 keV, 70 keV, 75 keV, and 80 keV. The HU values were measured at the three points of the reconstructed syringe axial image. The measurements were taken 1,620 times in total. In the analysis of the HU values according to the changes in keV and dilution ratio of the contrast agent, the highest and lowest HU values were obtained from dilution ratio 8:2 and dilution ratio 3:7, respectively, across every MonoE in the comparison of HU according to dilution ratio per MonoE (p<0.05), while the highest and lowest HU values were obtained from 40 keV and 80 keV, respectively, across all dilution ratios in the comparison of HU according to MonoE per dilution ratio (p<0.05). For the correlation per each parameter, a negative correlation of -15.014 ± 0.298 was found for HU per keV (R²=0.519) and a negative correlation of -61.372 ± 3.608 was found for HU per dilution ratio (R²=0.152) (p<0.05). To conclude, an increase in keV or dilution ratio of the contrast agent was shown to decrease the HU, and the findings in this study are anticipated to serve as the basic data in the research of HU-related parameters in Spectral CT.

• Journal of the Korean Society for Railway
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• v.16 no.5
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• pp.386-393
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• 2013

In this study, the so-called repeated plate load bearing test (RPBT) used to get $E_{v2}$ values in order to check the degree of compaction of subgrade, and to get design parameters for determining the thickness of the trackbed foundation, is investigated. The test procedure of the RPBT method is scrutinized in detail. $E_{v2}$ values obtained from the field were verified in order to check the reliability of the test data. The $E_{v2}$ values obtained from high-speed rail construction sites were compared to converted modulus values obtained from resonant column (RC) test results. For these tests, medium-size samples composed of the same soils from the field were used after analyzing stress and strain levels existing in the soil below the repeated loading plates. Finite element analyses, using the PLAXIS and ABAQUS programs, were performed in order to investigate the impact of the strain influence coefficient. This was done by getting newly computed $I_z$ to get the precise strain level predicted on the subgrade surface in the full track structure; under wheel loading. It was verified that it is necessary to use precise loading steps to construct nonlinear load-settlement curves from RPBT in order to get correct $E_{v2}$ values at the proper strain levels.

• Journal of Korea Water Resources Association
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• v.53 no.3
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• pp.155-166
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• 2020

In this study, we applied the Radar-AWS Rainrates (RAR), weather radar-based quantitative precipitation estimations (QPEs), to the Yongdam study watershed in order to perform the flood runoff simulation and calculate the inflow of the dam during flood events using hydrologic model. Since the Yongdam study watershed is a representative area of the mountainous terrain in South Korea and has a relatively large number of monitoring stations (water level/flow) and data compared to other dam watershed, an accurate analysis of the time and space variability of radar rainfall in the mountainous dam watershed can be examined in the flood modeling. HEC-HMS, which is a relatively simple model for adopting spatially distributed rainfall, was applied to the hydrological simulations using HEC-GeoHMS and ModClark method with a total of eight independent flood events that occurred during the last five years (2014 to 2018). In addition, two NCL and Python script programs are developed to process the radar-based precipitation data for the use of hydrological modeling. The results demonstrate that the RAR QPEs shows rather underestimate trends in larger values for validation against gauged observations (R² 0.86), but is an adequate input to apply flood runoff simulation efficiently for a dam watershed, showing relatively good model performance (E_NS 0.86, R² 0.87, and PBIAS 7.49%) with less requirements for the calibration of transform and routing parameters than the spatially averaged model simulations in HEC-HMS.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.529-536
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• 2016

The purpose of this research is to evaluate the quality of Differential Police Response strategy. Although it has been approximately three years since these new police response systems were introduced, there is no research to evaluate them empirically. Using two types of statistical quality control techniques, Xbar-R control charts for variables data and P charts for attributes data, this study analyzes approximately 3,000 calls reported throughout the year 2012 to the 112 Integrated Dispatch Center in Ik-san police station. The Xbar-R control charts revealed that the police did not consistently respond to an emergency call for service (i.e., code one case) within 3 minutes. The P control chart also identified that there was a significant variation in the portion/number of defective calls where police failed to respond to non-emergency calls for service within 5 minutes. The results from this study suggest the police may need to review the target response time for code 1 and code 2 respectively.

• Korean Journal of Optics and Photonics
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• v.19 no.6
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• pp.394-399
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• 2008

An integral imaging system enabling enhanced depth of field by incorporating a pair of liquid-crystal (LC) lens arrays was proposed and demonstrated. The lens arrays exhibit two different refractive indexes depending on the light polarization. The proposed LC lens array I and II were implemented by depositing a ZLI-4119 LC and an E-7 LC, respectively, on top of a lens-array substrate in glass. When the two LC lens arrays were aligned appropriately, a birefringence was obtained for a specific light polarization in such a way that the incoming light sees different refractive indexes for them. As a result, the focal length associated with the imaging system utilizing the LC lens arrays was adaptively varied, thereby enhancing the depth of field for the image reconstruction. We have theoretically analyzed the proposed integral imaging system with the $LightTools^{(R)}$ to confirm that the focal length could be adjusted with the help of the birefringent lens array. Finally the proposed imaging system successfully reconstructed the objects. The birefringent lens array employing the ZLI-4119 LC produced a real image with the focal length of 680 mm, while the other using the E-7 LC yielded a virtual image with the focal length of -29 mm.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.2C
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• pp.71-79
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• 2009

This study is to develope the resilient modulus prediction model, which is the function of mean effective principal stress and axial strain, for three types of railroad trackbed materials such as crushed stone, weathered granite soil, and crushed-rock soil mixture. The model consists of the maximum Young's modulus and nonlinear values for higher strain, analogous to dynamic shear modulus. The maximum value is modeled by model parameters, $A_E$ and the power of mean effective principal stress, $n_E$. The nonlinear portion is represented by modified hyperbolic model, with the model parameters of reference strain, ${\varepsilon}_r$ and curvature coefficient, a. To assess the performance of the prediction models proposed herein, the elastic response of a test trackbed near PyeongTaek, Korea, was evaluated using a 3-D elastic multilayer computer program (GEOTRACK). The results were compared with measured elastic vertical displacement during the passages of freight and passenger trains at two locations, whose sub-ballasts were crushed stone and weathered granite soil, respectively. The calculated vertical displacements of the sub-ballasts are within the order of 0.6mm, and agree well with measured values. The prediction models are thus concluded to work properly in the preliminary investigation.