• Journal of Educational Research in Mathematics
• /
• v.24 no.2
• /
• pp.205-225
• /
• 2014

This study analyzed how two sixth graders recognized, generalized, and represented functional relationships in exploring geometric growing patterns. The results showed that at first the students had a tendency to solve the given problem using the picture in it, but later attempted to generalize the functional relationships in exploring subsequent items. The students also represented the patterns with their own methods, which in turn had an impact on the process of generalizing and applying the patterns to a related context. Given these results, this paper includes issues and implications on how to foster functional thinking ability at the elementary school.

• Journal of Korean Society of Transportation
• /
• v.27 no.5
• /
• pp.97-111
• /
• 2009

Image-based traffic information collection systems have entered widespread adoption and use in many countries since these systems are not only capable of replacing existing loop-based detectors which have limitations in management and administration, but are also capable of providing and managing a wide variety of traffic related information. In addition, these systems are expanding rapidly in terms of purpose and scope of use. Currently, the utilization of image processing technology in the field of traffic accident management is limited to installing surveillance cameras on locations where traffic accidents are expected to occur and digitalizing of recorded data. Accurately recording the sequence of situations around a traffic accident in a signal intersection and then objectively and clearly analyzing how such accident occurred is more urgent and important than anything else in resolving a traffic accident. Therefore, in this research, we intend to present a technology capable of overcoming problems in which advanced existing technologies exhibited limitations in handling real-time due to large data capacity such as object separation of vehicles and tracking, which pose difficulties due to environmental diversities and changes at a signal intersection with complex traffic situations, as pointed out by many past researches while presenting and implementing an active and environmentally adaptive methodology capable of effectively reducing false detection situations which frequently occur even with the Gaussian complex model analytical method which has been considered the best among well-known environmental obstacle reduction methods. To prove that the technology developed by this research has performance advantage over existing automatic traffic accident recording systems, a test was performed by entering image data from an actually operating crossroad online in real-time. The test results were compared with the performance of other existing technologies.

• 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.

• Journal of Digital Convergence
• /
• v.14 no.8
• /
• pp.407-413
• /
• 2016

This research is aimed to discuss for Korean cultural contents; symbol structure of Minwha painting which not only expresses openness, flexible expression and methods of communication of our ancestors but also possibly passes down as precious cultural heritage to modern society with new developed mediums. From this perspectives, as a method of research, modern jewelry design is created through digital process with linguistics analysis of its symbol structure that contains universal wishes of people. As a result, this research showed jewelry design and design process, titled "Blossom" and "Big Smile" grafting modern technology of 3D digital tool onto universal meaning symbolized by Peony flower, wealth and honor, and also grafted modern manufacturing methods of 3D printing and laser cut onto openness and flexible thinking in symbol structure in Minwha.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2016.05a
• /
• pp.78-78
• /
• 2016

다이옥산, 페놀 등의 오염물질 유출로 인한 수질오염사고 발생시 사건 유형에 따라 단수로 인하여 국민들이 불편 겪거나 및 유해물질에 노출되는 등 안전성에 대한 우려가 있다. 본 연구는 수질 오염사고 발생시 댐 추가방류를 통해 위와 같은 문제를 해소하는데 기여하여 단수 등으로 인해 소비자들이 겪을 수 있는 불편을 방지하여 소비자효용의 감소를 줄이고, 안전성측면에서 수자원에 대한 소비자효용을 증가시키는 편익을 추정하고자 한다. 본 연구는 제주도 제외 전국 1,000 가구를 대상으로 한 일대일 개별면접 방식의 설문조사 수행하여 자료를 얻었고, 이 자료를 바탕으로 가구당 WTP의 대푯값을 추정하기 위해 KDI의 CVM 분석지침(2012)을 적용하였다. 수질오염사고 발생시 댐 추가방류에 대한 대푯값 WTP는 2,132.7(원/년/가구)로 추정되었다. 또한 추정결과 상수항 및 제시금액 항의 추정계수는 1.1451(t-값 5.83)와 -0.7286(t-값-5.54)로 모두 유의수준 1%에서 통계적으로 유의하여 설문조사가 제대로 수행되었음을 확인하였다. 국내에는 수질개선과 관련된 다양한 연구들이 존재하지만 댐 추가방류를 통한 수질오염사고 해소 편익 등과 특정사안에 대한 연구들은 존재하고 있지 않다. 따라서 본 연구의 분석결과는 수질 오염 사고로 인한 댐 추가방류의 가치에 대한 선제적인 연구로서 방법론적인 지침과 향후 수자원 개발 및 활용을 위한 정량적인 정보로 활용될 수 있을 것이다.

• 한국공간정보시스템학회:학술대회논문집
• /
• 2007.06a
• /
• pp.194-199
• /
• 2007

최근 차량증가에 따라 교통사고가 날로 증가하고 있고, 안전운전을 위한 보조장치 개발의 필요성이 증대되고 있다. 특히 교통사고 원인중 운전자의 졸음으로 인한 사고가 30%에 달하고 있어 졸음운전 예방장치의 개발이 시급한 실정이다. 이에 본 연구에서는 졸음운전예방을 위한 효율적인 졸음경보 장치시스템을 제안한다. 제안하는 방법은 HRV와 안구활동 신호를 BP(역전파알고리즘)을 이용 보다 더 정확한 측정 및 판단을 행하여 운전자에게 음성경고를 보내주는 방식이다. 제안된 방식은 기존의 연구된 피부전기활동, 영상처리를 이용한 졸음운전 감지 시스템, 심박변동신호 분석 방법보다 훨씬 효율적인 졸음경보를 할 수 있을 것으로 기대된다.

• Proceedings of the KAIS Fall Conference
• /
• 2012.05b
• /
• pp.541-544
• /
• 2012

화석연료 고갈로 인해 전기자동차의 발전이 이루어지면서 현재 무선충전용 급집전 시스템 개발을 통하여 이 시스템의 확산 및 보급에 필요한 기반시설 및 구축의 경제성확보가 중요한 실정이다. 이에 무선전력전달의 운용방식의 발전에 따라 차량의 급전부 및 전기설비 구축이 중요한 요소로 대두되고 있다. 하지만 수변전부에서 급전부까지의 전력공급 및 전기설비에 대한 협조체계가 없어, 이에 본 논문에서는 급전부에 전력전달시 발생되는 전압강하를 분석하고 무선 전력전달방식에서 고압측에서 발생되는 각종 지락사고 및 단락사고를 해석하여 문제점분석을 통해 안정적인 전력전달방식을 구축하고자 한다.

• Proceedings of the KAIS Fall Conference
• /
• 2008.11a
• /
• pp.25-28
• /
• 2008

최근 인터넷과 같은 통신 기술 및 컴퓨터의 계산 능력이 급속도로 발전함에 따라, 많은 업무들이 온라인을 통해서 이루어지고 있다. 온라인 서비스의 편리함 이면에는, 전자 금융의 보안 허점을 노린 해킹시도가 끊이지 않고 있으며 금전적인 이득을 노린 금융 보안 사고들이 자주 발생하고 있다. 이러한 보안 사고를 막기 위해서 사용되는 기존의 인증 방식을 확인하고 인증 방식의 문제점을 분석한다. 본 논문에서 새로운 3-factor 인증 방식을 제안함으로써 기존의 인증 방식의 문제점을 해결하고, 기존 인증 방식보다 보안성이 강화된 인증 체계의 구현과 다양한 보안 서비스 제공, 안전한 금융 서비스 제공이 가능할 것으로 기대 된다.

• Journal of Korean Society of Transportation
• /
• v.29 no.4
• /
• pp.53-62
• /
• 2011

This study discusses the effectiveness of safety management programs resulted from examining crash data collected during the period of implementation of the programs by a commercial transport company. For the analysis, two tye of comparison approaches are adopted: 1) a study comparing before-after of the implementation of a safety program, and 2) a study comparing a traffic accident index for various target groups. Technically, the effect of the safety management program is derived by eliminating both the 'regression to the mean' and the changing trend in the traffic accident index. The results show that safety management programs are effective to prevent traffic accidents, whereas company type appears irrelevant. The results also show that the effectiveness is significantly different depending on the intensity of safety management program and company size. In addition, a reciprocal effect is very likely to existamong the combination of these variables. This indicates that in order to improve the accident reduction effectiveness of such programs, the development and application of safety management programs based on both safety management strength and company size are required.

• Journal of Elementary Mathematics Education in Korea
• /
• v.1 no.1
• /
• pp.123-140
• /
• 1997

Researchers have insisted that mathematics should be learned not as a product but as a process. Nevertheless school mathematics has chosen ‘top-down’ method and has usually instilled into the mind of students the mathematical concepts in the form of product. Consequently school mathematics has been teamed by students without the process of inquiring and mathematical thinking. According to Freudenthal, it is a major source of all problems of mathematics education. He suggested mathematising as the method for 'teaching to think mathematically' 'Teaching to think mathematically' through the process of mathematization, interpreting and analysing mathematics as an activity, is a means to embody the purpose of mathematics education.