• The Journal of Korean Association of Computer Education
• /
• v.12 no.6
• /
• pp.11-19
• /
• 2009

In the knowledge-information-oriented society, it is difficult for students to solve lots of problems or adapt themselves to society just by using simple knowledge. Students have to develop individual problem solving ability and creative, logical thinking ability. They can develope these abilities by learning computer programming. This thesis studies the influences of a flow-chart learning on the logical thinking ability in Scratch using programming learning. The findings identify that the making algorithm by using flow-chart is more effective in developing logical thinking ability then the making algorithm by using pseudo-code.

• Journal of Korean Society of Transportation
• /
• v.34 no.4
• /
• pp.354-372
• /
• 2016

This study identified factors affecting the crash severity at freeway work zones. A nice feature of this study was to take into account the characteristics of work zone traffic management in analyzing traffic safety concerns. In addition to crash records, vehicle detection systems (VDS) data and work zone historical data were used for establishing a dataset to be used for statistical analyses based on an ordered probit model. A total of six safety improvement strategies for freeway work zones, including traffic merging method, guidance information provision, speed management, warning information systems, traffic safety facility, and monitoring of effectiveness for countermeasures, were also proposed.

• Journal of The Korean Association For Science Education
• /
• v.29 no.1
• /
• pp.10-21
• /
• 2009

The purpose of this research was to investigate science teachers' thoughts about hypotheses and rules related to the contents of ninth grade 'Construction of Matter' and 'Rules of Matter Change' chapters. The changes of their thoughts through experience of the abduction viewpoint were also analyzed. Twenty-two science teachers in the masters course took lessons and discussions related to the abduction viewpoint in the course of three weeks. The changes in thought of four teachers selected among them were investigated through individual interviews and their reports. From the investigation, it was found that the two teachers who had not recognized the problems of textbook content order could distinguish rules and hypotheses after the lessons and discussions. The two teachers who had recognized the problems before the lessons gained the abduction viewpoint through the lessons. They also recognized new opinions related to teaching styles for students and the meaning of the abduction viewpoint on education.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.18 no.2
• /
• pp.12-28
• /
• 2019

Road geometry is one of the many factors that cause crashes, but the effect on traffic accident depends on weather conditions even under the same road geometry. This study identifies the variables affecting the crash severity by matching the highway accident data and weather data for 14 years from 2001 to 2014. A hierarchical ordered Logit model is used to reflect the effects of road geometry and weather condition interactions on crash severity, as well as the correlation between individual crashes in a region. Among the hierarchical models, we apply a random intercept model including interaction variables between road geometry and weather condition and a random coefficient model including regional weather characteristics as upper-level variables. As a result, it is confirmed that the effects of toll, ramp, downhill slope of 3% or more, and concrete barrier on the crash severity vary depending on weather conditions. It also shows that the combined effects of road geometry and weather conditions may not be linear depending on rainfall or snowfall levels. Finally, we suggest safety improvement measures based on the results of this study, which are expected to reduce the severity of traffic accidents in the future.

• Journal of Korean Society of Transportation
• /
• v.30 no.2
• /
• pp.127-136
• /
• 2012

Multi-car rear-end collision accidents have three categories: sequential collision from the rear which is commonly referred to as chain reaction collision, sequential collision from the front, and mixed-order collision. This paper suggests several effective methods of reconstruction analysis for multi-car rear-end collision accidents. First, by incorporating the traditional empirical method which uses vehicle damage caused by brake dive and passenger injuries, with results of theoretical analysis made within mechanics of rigid body, it is made possible for the method to be put to immediate practical use. A methodology to precisely analyze multi-car rear-end collision accidents was suggested using a simulation program simultaneously with a video event data recorder which is starting to be widely used in domestic vehicles. To go beyond the simple intuitive analysis of the video event data recorder, the simulation analysis based on the results of video analysis was executed to acquire various information, so that the causes and responsibility could be clearly stated.

• The Journal of Korean Association of Computer Education
• /
• v.11 no.4
• /
• pp.1-12
• /
• 2008

This paper proposes basic algorithmic thinking based problem models applicable immediately without additional learnings and it problems basic problems and evaluation methods using material factors in an elementary course of mathematics For these purposes, an algorithmic thinking based problem model and it's basic problem models are proposed based on flowchart design methods with 5 degrees of difficulties. And algorithmic thinking based basic problems are developed by applying the proposed basic problem models into material domain in an elementary course of mathematics. And this paper proves the validity of developed basic problems in defining then as algorithmic thinking based basic problems through experiments and statistical analyses. The experimental results are analyzed in views of variety and effectiveness evaluation of answer algorithms and suitability of allocating 5 degrees of difficulties to the developed basic problems.

• Journal of Korean Society of Transportation
• /
• v.30 no.3
• /
• pp.57-70
• /
• 2012

Variable speed limit(VSL) is a useful speed management tool for alleviating traffic congestion and enhancing traffic safety. The purpose of this study is to identify promising freeway segments for safety enhancement through VSL operations. An ordered probit model was adopted to capture factors affecting freeway crash severity that can be used to support decision making for selecting the promising segments. Pseudo elasticity and marginal effects, which are outcomes of the ordered probit analysis, were used to determine priority of promising segments for traffic safety. The results of this study would be useful in installing VSL systems and developing traffic control and operations strategies in practice.

• Nuclear Engineering and Technology
• /
• v.24 no.3
• /
• pp.243-251
• /
• 1992

Behavior of loop seal formation and clearing during small break loss of coolant accident is investigated using the RELAP5/MOD 2 and /MOD3 codes with the test of SB-CL-18 of the LSIF (Large Scale Test Facility）. The present study examines the thermal-hydraulic mechanisms responsible for early core uncovery including the manometric effect due to an asymmetric coolant holdup in the steam generator upflow and downflow side. The analysis with the RELAP5/MOD2 demonstrates the main phenomena occuring in the depressurization transient including the loop seal formation and clearing with sufficient accuracy. Nevertheless, several differences regarding the evolution of phenomena and their timing have been pointed out in かe base calculations. The RELAP5/MOD3 predicts overall phenomena, particularly the steam generator liquid holdup better than the RELAP5/MOD2. The nodalization study in the components of the steam generator U-tubes and the cross-over legs wiか the RELAP5/MOD3 results in good prediction of the loop seal clearing phenomena and their timing.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2012.01a
• /
• pp.119-122
• /
• 2012

정보화시대에 요구하는 인재는 문제를 인식하고 이런 문제를 풀기 위해 다양한 전문가들과 함께 창의적인 사고를 통해 해결책을 제시하는 인물이다. 정보영재교육의 목표 역시 창의적 인재를 기르는 데 있으나, 프로그래밍과 알고리즘 교육은 특정 프로그래밍 언어의 사용법이나 문법 위주의 교육, 정렬 및 탐색과 같은 알고리즘 그 자체에 치중함으로서 이러한 목표에 도달하고 있지 못하다는 지적이 많다. 이에 본 논문에서는 창의적인 알고리즘을 설계하고 개발하는데 필요한 사고력, 즉 사고 과정에 대해 안내하고 생각하는 알고리즘적 사고력을 기르기 위한 방안으로 실생활 주제의 이야기 쓰기를 활용하는 교수 학습 프로그램을 제안하였다. 반성적 사고와 창의성을 기르는 데 효과적인 것으로 알려진 이야기 쓰기 활동에서 출발하여 사건 요소 추출과 시간적 질서 분석하기, 순서도로 알고리즘 표현하기, 동료 학습자와 토의하기 등의 과정을 통해 알고리즘적 사고력을 향상시킬 수 있도록 하였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.5 no.2 s.10
• /
• pp.61-71
• /
• 2006

The main purpose of this study is to search a method for reducing traffic accident at signalized intersections. One of the important factors for this is the Left-turn phase sequence. In 1985, the operational principle of Left-turn phase Sequence was changed from Lagging left-turn to Leading left-turn in Korea. Then there was a resonable motive-no exclusive left turn-lane and narrow intersection. So, it is necessary to evaluate the performance difference between Leading and Lagging left -turn phase Sequence. The process of this study is as follows: $\cdot$ First, all the intersection was divided three parts for analysis the traffic safety: Inside part of an Intersection, Crosswalk, Intersection approach and exit. $\cdot$ Second, a safety analysis was performed by using the concepts of 'Effective interphase Period(EIP)' and 'Conflict method' The Study result is that the benefit of of phase Sequence changes from Leading to Lagging phase were significant. For an example the Accident cost will reduced about 41.8 billion won per year in korea.