Earticle

방과후활동을 선택하는 부모와 학생 즉, 의사결정권자는 인 네트워크를 통해 정보를 수집하고 교환하는데 이 과정 에서 정보연쇄효과가 일어날 수 있다. 정보연쇄효과는 방과후활동의 선택을 한 결정요인을 변화시킬 수 있으며, 나아가서는 방과후활동을 변경하게 한다. 본 논문에서는, 기계학습 장소의 공공 데이터 집합을 활용하여, 정보연쇄효과에 근거한 방과후활동에 한 결정요인에 하여 연구한다. 우리는 정보연쇄효과가 발생한 경 우에 방과후활동을 선택하는데 어떤 향을 주는지 알기 해 CEAS를 제안하고 그것을 통해 실험한다. CEAS는 학교 활동의 선택에 한 결정요인이 어떤 과정을 통해 변화하는지 보여으로써 반인 교육정책 수립에 도움을 것으로 기한다.

Parents and students, who are the decision-makers in the process of selecting after-school activities, collect information through their personal networks. Information cascade can occur in this process. Information cascade can change the determinants for selection, and furthermore it makes changes in after-school activities. In this paper, we study the determinants of after-school activities based on information cascade using the public data sets of Machine Learning Repository. We also propose CEAS as a tool to understand the effects of information cascade on the selection process of after-school activities. The CEAS shows the process of how the determinants for selecting after- school activities change during information cascade. Therefore, this study will be helpful for policy-makers in establishing education policies.

현재 야외공연장의 민원으로 인한 소음에 대한 문제점 해결의 필요성이 대두되기에 본 연구를 시작하였다. 상용 프로그램 Cadna-A를 활용하여 야외 공연장 소음지도 작성을 하였고 실제 야외 공연장 2 곳에서 소음을 측정 하였다. 실측값과 예측값의 비교를 통하여 컴퓨터 시뮬레이션의 신뢰성을 검증하였다. 음원의 지향성의 따른 영향을 컴퓨터 시뮬레이션과 측정을 통해 분석하였다. 지향성 음원과 무 지향성 음원을 비교한 결과 0 .4~13 .4 dB의 차이가 발생하였다. 지향각도에 따른 음원의 영향을 기준각도 (0°)와 각 지향각도 45°, 90°, 135°, 180°를 비교한 결과 예측값(측정값)의 차이가 0.​​7(0.2) -20.0(16.2)dB 이었다. 이는 음원의 지향성이 야외공연장의 성능을 제어하는​​데 큰 영향을 가지고 있음을 발견하였다

The purpose of this study was to investigate the manufacture of noise map and the influence on the characteristics of sound source at outdoor performance hall. By utilizing a commercially available program Cadna-A, noise map creation of the outdoor performance hall did and measured the noise at actual outdoor performance hall 2 places. Through the comparing to the measured actual value and the predicted value of the noise, the reliability of computer simulation was verified. The influence of the directivity of the sound source was analyzed by computer simulation and the measurement. As a result, the noise difference comparing the directional sound source and the non-directional sound source was 0.4-13.4dB. And a result of comparison of the sound source in accordance with the directivity angle (0 °), the directivity angle 45 °, 90 °, 135 °, 180 °, the difference of predicted noise (measured noise) was 0.7(0.2)-20.0(16.2)dB. It was found that the directivity of sound source has large impact to control the noise of outdoor performance hall.

Unlike the western music nor the other Korean traditional music, Pansori has its own distinctive performing features. This means that there is a need for an exclusive Pansori theatre. In this basis, an optimal acoustical design process and its final design are presented in the paper. Acoustical target in this study was proposed in a previous research, which was described in terms of three acoustic parameters, reverberation time, clarity and the distribution of sound pressure level. According to the result of acoustic simulation, despite a dry condition, reverberation time of 0.7 to 0.8 seconds, the final design has quite an adaptable distribution of sound pressure levels all around the audience seats. This is accomplished by the deliberately arranged reflectors installed above the stage and in front of Gosu(the drummer). General acoustic designing scheme is absorptive ceiling, rear wall and rear side lateral wall and reflective/diffusive front lateral walls for some lateral early reflections.

An acoustic design was undertaken to a small sized multi-purpose hall. Two different sound sources were taken into account to analyze the acoustics of the hall; natural source and speaker source. Computer simulations were carried out to find appropriate acoustic design facotrs of the hall. Acoustic criteria including SPL, RT, C80, D50, RASTI were analized and presented in a visualized form. Finally, It was shown that the acoustical purpose of the multi-purpose hall was acquired. the current process of the acoustic design would be a model of building the multi-purpose hall in a small size town.

우주공간은 우주의 팽창을 가속화 시키는 것으로 생각되고 있는 암흑에너지, 중력과 물질 생성에 관여하고 있는 것으로 추정되고 있는 암흑물질, 그리고 수소와 헬륨이 분포해 있다. 사람이 인지하여 관측할 수 있는 우주 공간중의 입자의 영역에서, 대부분의 은하 중심인 블랙홀을 공전하고 있는 항성과 그 주위를 공전하는 위성들의 공전을 설명하기 위한 방법으로 뉴튼의 만유인력의 법칙(law of universal gravity)이나, 아인슈타인의 일반 상대성 이론(theory of relativity)이 있다. 우리은하에 속해있는 태양계에서 태양을 타원궤도로 공전하는 수성의 세차운동은 태양과 행성들 사이에서 작용하는 중력과 뉴튼의 중력방정식으로 많을 부분이 설명되지만, 수성의 근일점이 바뀌는 현상인 타원궤도의 축이 100년에 약 43초씩 이동하는 현상을 설명하지 못했다. 아인슈타인은 이를 공간의 왜곡이라는 사실로 풀어냈다. 원뿔 내 구체의 움직임을 해석하는 것은 왜곡된 공간을 운행하는 천체들의 운동을 해석하기 좋은 모델이다. 본 논문에서는 상대성이론 근거하여 천체들의 질량으로 왜곡된 우주공간에서 항성주위를 공전하는 행성의 괘도운동을 원뿔 내 구체의 움직임으로 해석하도록 구현되어 있는 시뮬레이션 프로그램을 이용하는 방법을 보인다. 오픈소스물리학 사이트에서 제공하는 API와 자바의 Swing, 3D 패키지에 있는 API가 시뮬레이션을 위해 사용되었다. 원뿔 내를 운행하는 천체의 다양한 자취추적을 위하여 타원의 근지점, 원지점, 원뿔의 각도, 그리고 두 구체의 거리를 변수로 시뮬레이션 하였으며, 태양계에 속한 다양한 행성들의 운행궤도를 시뮬레이션 할 수 있었다.

The full extent of damage depend greatly on the quick and rational decision making by the incident commander soon after the disaster. The decision that everybody should wait by the captain, not to enter into the ship by the first dispatched incident commander, broadcasting failure have brought about a huge loss of life at Sewol cruise ship incident. Thus this study reviews the training and education system supporting the rational crisis decision making performed by the incident commander to cut off the expansion of disaster which is caused by the failure of the incident situation awareness and the decision making described above.

EQPS (Effluent Quality Predication System)로 간헐 주입 SBR (Sequencing Batch Reactor) 운전 성과를 파악하였다. EQPS는 질산화에 대한 pH 영향을 파악할 수 있는 관계로 질산화를 통해 발생된 산을 중화시키기 위한 가성 소다 필요량 을 파악할 수 있다. SBR 후단에 설치된 화학적 인 제거 시설이 인과 고형물을 제거하는 관계로 질소제거가 간헐 주입 SBR 의 주 목적이다. 동일한 유기물량을 1, 2, 3, 3, 4, 5회로 나누어 주입시키는 경우 3회로 나누어 주입하는 경우 질소제거 효 율은 93.1%로 가장 높고, 5회로 나누어 주입시키는 경우는 77.9%로 가장 낮은 것으로 니타났다. 시뮬레이션은 간헐 주입 횟 수가 증가할수록 MLSS농도가 낮아지는 것을 보여주어 간헐 주입을 사용하는 경우, 최적의 질소제거를 위해서는 질산 화에 대한 평가가 선행되어야 한다. 간헐 주입 SBR에서 유입수 분할 횟수는 시뮬레이션을 통해 파악되어야 한다.

The performance of intermittent feed SBR (Sequencing Batch Reactor) was evaluated by simulator called as EQPS (Effluent Quality Predication System). Since the EQPS can simulate the effect of pH on nitrification, the required amount of caustic soda to neutralize acids produced from nitrification can be estimated. Also, chemical phosphorus removal can be simulated. Since the phosphorus and particulate are removed at chemical phosphorus removal unit followed by SBR, the main objective of intermittent feed SBR is nitrogen removal. Five feeding schedule such as 1, 2, 3, 4, and 5 divided feeds with same organic load were studied and the simulation revealed that the 3 divided feed showed the highest percentage of nitrogen removal as 93.1 %, in contrast that the 5 divided feed showed the lowest percentage of nitrogen removal as 77.9 %. Also, simulation revealed that the higher division of feed, the lower the concentration of MLSS (Mixed Liquor Suspended Solid) in SBR. Since the MLSS concentration is inversely proportional to the number of feed, the nitrification that is prerequisite of denitrification has to be carefully evaluated when influent to SBR is divided. Before considering the division of influent to maximize nitrogen removal, the number of division has to be determined by simulation before implementing.

새로운 미디어의 부상과 발전은 새로운 정보 혁명을 형성하고 교육 분야로 스며들었고, 이것은 축구 교습이 엄청난 도전에 직면하게 만든다. 축구 교육에서 합리적이고 효과적인 교수법을 선택하는 것은 학생들이 "행복한 스포츠" 분위기 에서 축구 지식과 기술을 배우게 할 뿐만 아니라, 스포츠에 대한 학생들의 관심을 자극하고 평생 체육에 대한 학생들의 의식을 길러줄 수 있다. 현재의 전통적인 교수법과 비교해서 멀티미디어 교수법은 텍스트, 오디오, 그래픽, 애니메이션 및 기타 정보 제공자를 결합하여 교실 분위기를 활성화시키고, 학생들의 학습에 대한 관심을 크게 향상시키며, 교육 내용 을 확대할 수 있다. 강의실 강의는 더 이상 시간과 공간 제한의 대상이 되지 않으며, 이는 강의 효과 등을 향상시킨다. 동시 에, 멀티미디어 교육 방법은 축구 실외 교실의 큰 환경, 체육 교사의 실제 운영 수준 및 기타 요인에 의해 제한된다. 따라서, 본 연구는 MAYA프로그램을 통해 캐릭터와 축구의 움직임을 시뮬레이션하기 위해 멀티미디어 교육 방법의 컴퓨터 시뮬 레이션 기술을 실험 연구를 위한 축구 교단에 적용한다. 멀티미디어 교습에 의해, 운동 재등장이 실현되어, 축구 교습에서 컴퓨터 운동 시뮬레이션의 가치를 검증한다. 이 논문은 MAYA를 통해 수치와 축구 동작을 시뮬레이션하고, 멀티미디어 교육을 통해 동작 반복을 달성하며, 이는 축구 교습에서 컴퓨터 운동 시뮬레이션의 적용을 검증한다.

The rise and development of new media have formed a new information revolution and permeated into the field of education, which makes football teaching face enormous challenges. In football teaching, choosing reasonable and effective teaching metods can not only make students learn football knowledge and skills in the atmosphere of "happy sports", but also stimulate students' interest in sports and cultivate students' consciousness of lifelong physical education. Compared with the current traditional teaching methods, the multimedia teaching method combines text, audio, graphics, animation and other information carriers, enlivens the classroom atmosphere, greatly improves the students' interest in learning, and can expand the teaching content. Classroom Teaching is no longer subject to time and space restriction, which enhances the teaching effect and so on. At the same time, the multimedia teaching method is limited by the big environment of football outdoor classroom, physical education teachers' actual operation level and other factors. Therefore, this study applies the computer simulation technology in the multimedia teaching method to the football teaching for experimental study, in order to discuss the feasibility and timeliness of the teaching method in football teaching; simulates the characters and the football movements through MAYA. By means of multimedia teaching, the movement reappearance is realized, which verifies the value of computer motion simulation in football teaching. Through MAYA, this paper simulates the figures and football actions and achieves the action repetition through multimedia teaching, which verifies the application of Computer Motion Simulation in football teaching.

본 연구는 화재 발생 시 스마트폰 네비게이션 어플리케이션을 이용한 화재 대피 유도 서비스 시스템이 화재대피 시간에 어떤 영향을 미치는지 살펴보고자 하는 연구이다. 컴퓨터 시나리오 시뮬레이션에서 네비게이션 어플리케이션을 사용하였을 때 대피시간이 22초 단축되었고 실증시뮬 레이션 또한 네비게이션 어플리케이션을 사용하였을 때 대피시간이 40초 감소되어 화재 발생 시 피난 시간 단축에 효과적이라는 점을 알 수 있다. 실증 시나리오 시뮬레이션을 한 결과는 피난유도를 실시한 경우가 실시하지 않은 경우보다 피난 종료까지 시간이 39초 더 빠르게 나타났다. 실증 시나리오 시뮬레이션은 피난 경로에 병목현상이 발 생하지 않았고 이로인해 컴퓨터 시나리오 시뮬레이션과 실증 시나리오 시뮬레이션의 대피 완료 소요시간의 차이가 발생하였다. 추후 시나리오 시뮬레이션에 학생실습 연구에 기여할 것이다.

This study examined how the fire evacuation induction service system using a smartphone navigation application in the event of a fire affects the fire evacuation time, and the following conclusions were drawn. 1. The evacuation time was reduced by 22 seconds when the navigation application was used in computer scenario simulation. Even in the demonstration simulation, the evacuation time was reduced by 40 seconds when the navigation application was used. This indicates that the navigation application is effective in shortening the evacuation time in case of fire. 2. As a result of the demonstration scenario simulation, the time until the end of evacuation was 39 seconds faster in the case of evacuation guidance than in the case where it was not conducted. 3. No bottlenecks occurred in the evacuation route during the demonstration scenario simulation. As a result, there was a difference in the time required to complete the evacuation between the computer scenario simulation and the demonstration scenario simulation.

Hydro-forming technology is a technology that will replace the existing press-forming technology and is used in various industry range from automotive parts to electronic products. The advantage of this technology is that it has dramatically changed the existing processing method, and it can be said that the process reduction due to the reduction of parts, cost reduction, and high precision are mentioned. In this study, it is intended to present a design process using computer simulation by changing the sub-frame for automotive parts produced with the existing press forming technology to the hide-forming method. To this end, it is intended to use it as part design data by comparatively analyzing the cross-sectional shape and thickness reduction, which are the major factors necessary to determine the successful development of the developed parts.

As screen printing is changed by automation recently, could print more exactly. However, must suffer great many trial and error to have still gotten perfect result. By the way, at this step, fair time and money should be invested. Therefore, if search for optimum condition in early time visualizing screen printing process using simulator program before progress printing, is judged that may be correct and gets printing result efficiently. In this paper, searched optimum printing speed and ink viscosity using FLOW-3D program. Also, the result could confirm truth that is agreeing almost with experiment contents. Through this, is thought that may expect extension of screen printing wide application that vivify advantage of screen print if use simulation program.

In gravure printing, the amount of ink fill into the cells has a great effect on the qualities of final printed products. And printability of final products is determined by every kinds of variables. Ink transfer process is not verified scientifically because gravure cell is small and printing speed is rapid. In order to understand the ink transfer mechanism of conventional gravure, this study is performed using the Computational Fluid Dynamics Evaluation. Flow-3D simulation software is used for considering of Newtonian flow. Among the various factors, this study have dealt with gravure cell types used computer simulation in order to define distinctive features in ink flow in the cell. The results of simulation, it defined the distribution of pressure, speed, stream function, viscosity, shear rate, surface tension during the gravure printing. It is founded out the difficulties and characteristics according to the printing speed and viscosity of Gravure ink.

In gravure printing, the amount of ink from cells has a great effect on the qualities of final printed products. And printability of final products is determined by every kinds variables. Ink transfer process is not verified scientifically because gravure cell is of small size and print speed is rapid. Therefore in order to study of ink transfer mechanism, this study is using the Computational Fluid Dynamics Evaluation. Polyflow 3-10 simulation software is used for considering of non-Newtonian flow. Among the various factors, this study have dealt with gravure cell types used computer simulation in order to define distinctive features in ink flow and transfer. The results of simulation, it defined the distribution of pressure, speed, stream function, viscosity, shear rate during the gravure printing. It is fined out the difficulties and characteristics according to the shape of cell types. Through this study, the condition of gravure printing is depending on the print condition and characteristic of cells.

In gravure printing, all of the ink in the gravure cells does not leave the cell onto the substrate. The ink transfer from plate to paper in the gravure printing was simulated by computer. A few studies have dealt with cell withdrawal with simplified Newtonian flow models however, this work was performed with the non-Newtonian inks with different simulation software.

포장된 복합비타민의 보관수명을 예측하기 위한 수학모델을 수치해석의 방법 중 finite difference method을 이용한 컴퓨터 프로그램을 개발하였다. 이 컴퓨터 프로그램에는 포장재료의 수분확산계수와 용해도를 비롯한 식품의 수분확산계수 등 다양한 인자들을 포함하고 있다. 포장재료를 통과하는 수분의 물질전달은 G.A.B water sorption isotherm을 기본으로 했다. 본 연구에서는 비정상상태에서의 물질전달로 기본 수학모델링을 구하였다. 본 수학모델과 프로그램의 결과는 실험치와 비교하지 않았고 대신 특정한 경우를 가상하여 이에 존재하는 analytical solutions를 실제로 구하여 본 수학모델과 컴퓨터 프로그램의 신뢰도 측정을 하였다.

The computer simulation is presented of gravure ink transferring behavior and penetration to the paper when an gravure roller is used to transfer a printing ink onto a substrate. The three dimensional unsteady ink motion is simulated by Polyflow package software and experimented by IGT gravure printing test machine. The simulation is performed where the flow domain is bounded above by a stress free surface and bounded below by a moving substrate. Specific predictions are made for particular pattern of cells and substrates. Cell size and ink rheological properties are found to be the principal determination of transferring behavior. Simulation is currently restricted to the flow domain beneath the receding meniscus. Both Newtonian and shear thinning inks are considered.

With the development of many display technologies currently applied to them in the field of printed electronics, there have been many researches that high resolution printing for thin and uniform pattern. In this paper, printing ink flow properties in the reverse offset mechanism were simulated. The aim of this research is to expect the ink flow behavior between cliches to make fine pattern by a printing technique which is a reverse offset. The simulation results show that almost the same as the experiments and the flow behavior according to the ink film thickness and printing pressure changes could be expected.

Gravure printing is the most useful printing process than any other engraving printing method. According to the cell which is variable size and depth, ink is transferred substrates. So, the amount of ink from cells has a great effect on the qualities of final printed products. The variables effect on the printability of final products are proportion of the width and length, the rhelogical properties, roll speed etc. However the mechanism of gravure is difficult to study scientifically because of high speed and excessively small size of the cell. To approach the mechanism we experimented the real test by using gravure printability. The condition of variables of IGT is pressure and velocity. By using Polyflow 3. 10. 0 simulation software, we built up the theoretical model under the constant variables. Then, we compared the real test with the simulation results. Therefore, it is studied the mechanism of gravure scientifically and it can be analysed the effect of the variable conditions.