• Journal of Drive and Control
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• v.20 no.1
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• pp.8-15
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• 2023

With the recent trend of intelligence and automation of construction work, a double-blade road cutter is being developed that automatically enables cutting along the cutting line marked on the road using a vision system. The road cutter can recognize the cutting line through the camera and correct the driving route in real-time, and it detects the load of the cutting blade in real-time to control the driving speed in case of overload to protect workers and cutting blades. In this study, a vision system mounted on a double-blade road cutter was developed. A cutting route recognition technology was developed to stably recognize cutting lines displayed on non-uniform road surfaces, and performance was verified in similar environments. In addition, a vision sensor protection module was developed to prevent foreign substances (dust, water, etc.) generated during cutting from being attached to the camera.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10b
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• pp.997-1000
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• 2000

무선 인터넷 서비스에 대한 요구가 무선기술의 발전과 더불어 증가되고 있다. 하지만 현재의 인터넷 프로토콜인 IPv4에서는 IP의 이동 환경을 지원하지 못한다. 이에 여러 연구가 진행되고 있으며, IETF의 Mobile IP Working Group에서는 기존의 IPv4를 사용하면서도 이동환경을 지원하기 위한 이동 IP에 대한 연구를 진행하고 있다. 이에 본 논문에서는 인터넷에서 계층적이며 효율적인 이동성 지원을 위하여 영역과 도메인, 인터 도메인으로 세분화된 환경에서의 이동성 지원을 위한 기법을 제안한다. 본 논문에서는 하나의 이동 호스트가 특정 멀티캐스트 주소로 인식되어 멀티캐스트 라우팅 프로토콜에 의한 데이터 전송 서비스를 받는다. 이에 지속적인 이동성을 가진 이동 호스트에게 절단점 없는 서비스를 제공하기 위하여 동적 멀티캐스트 경로를 재설정 함으로서 경로 설정에 의한 오버헤드와 데이터전송의 지연을 최소화한다. 이러한 방법은 영역과 도메인, 인터 도메인의 계층적인 이동성을 지원함으로서 핸드오프 지연을 감소시키며. 홈 에이전트와 대응 노드에 부가되는 부하를 줄 일 수 있다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.1
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• pp.53-59
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• 2013

Since 1990s, the major recycling methods for mechanical recycling of FRP(Fiber Reinforced Plastics)boats has involved shredding and grinding of the scrap FRP in a new recycled product. But still it leads to secondary problem such as air pollution, unacceptable shredding noise level and few limited applications. This study is to propose a newly advanced method which is more efficient and environment friendly waste FRP regenerating system. As extracting FRP layer and making the recycled fiber for recycled-fiber reinforced concrete(RFRC) from waste FRP, the recycling process has some merits in a sense of the recycling energy and the environmental effects. In this study, for those tasks, spectro-chemical differentiation method and coloring water-soluble dye treatment makes the roving layer more distinguishable photophysically. Also that has remarkably reduced safety hazards and energy. Using the mechanical properties of polymers and composite, FRP with the orthotropic and laminated plastic structure has been easily separated in the new extracting system. Also the new method has introduced five kind of separating manuals for the some different compositions of FRP boats. The roving fiber of laminated glass-fiber layer is as good as the polyvinyl fiber which is cost-high commercial fiber to increasing strength of concrete products. The early study has shown the effectiveness of laminated glass-fiber layer which also is chemical-resistant due to the resin coating. These results imply that more efficient and environment friendly recycled glass fiber can be better applied to the fiber reinforced concrete(FRC) substitute and this study also has shown wide concrete applications with RFRC from the waste FRP boat.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.1-7
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• 2013

During meiosis, genetic recombinants are formed by homologous recombination accompanying with the programmed double-strand breaks (DSBs) and strand exchanges between homologous chromosomes. The mechanism is generated by recombination intermediates such as single-end invasions (SEIs) and double-Holliday junctions (dHJs), and followed by crossover (CO) or non-crossover (NCO) products. Our study was focused on the analysis of meiotic recombination intermediates (DSBs, SEIs, and dHJs) and final recombination products (CO and NCO). We identified these meiotic recombination intermediates using DNA physical analysis under HIS4LEU2 "hot spot" system in budding yeast, Saccharomyces cerevisiae. For DNA physical analysis, when the hot spot locus is recognized by restriction enzyme from synchronous meiotic cells, the fragmented DNA that are forming recombination intermediates can be detected and quantified through Southern hybridization analysis. Our study suggests that this system can analyze the structural change of recombination intermediates during DSB-SEI transition, double-Holiday junctions and crossover/non-crossover products in meiosis.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.4
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• pp.53-62
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• 2022

Animal companionship is gaining popularity in Korea, and interest in dog walking is also increasing as a strategy to maintain the physical and mental health of dogs and dog owners. The purpose of this study was to investigate the perception and satisfaction of dog owners with the neighborhood environments for dog walking and to examine the willingness to pay (WTP) for an off-leash dog park. Of a total of 249 online survey respondents, 47.8% said they take a walk at least once a day and mainly walk around nearby neighborhoods or parks. Respondents showed a high attachment to their dogs and recognized that dog walks help increase physical activity and maintain the health of owners and their dogs. The satisfaction with neighborhood environments, such as attractive views and the connection of walking trails, was low, and there was a high demand for off-leash dog parks. The truncated mean WTP was estimated to be 85,618 Korean Won, and the result of regression analysis and t-test revealed that walking frequency and the satisfaction with dog walking facilities were statistically significant in the WTP. In order to encourage dog walking to promote physical activity and health, more attention needs to be devoted to improving neighborhood environments for dog walking.

• Restorative Dentistry and Endodontics
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• v.29 no.1
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• pp.30-35
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• 2004

치아 미백술은 치아의 심미성을 향상시키는 가장 보존적인 방법의 하나로 인식되어져 왔으며 최근의 심미치과에 대한 관심의 증가와 함께 그 빈도가 급격히 증가하고 있는 술식의 하나이다. 일반적으로 치아 미백술 후 바로 접착수복을 할 경우 결합력이 감소하는 것으로 알려져 있으며 이를 해소하기 위해 일정시간 경과 후 접착수복 술식을 시행할 것을 권장 하고 있다. 자가산부식형 (self-etching primer system) 접착제는 기존의 접착제와 다른 성분으로 인해 치아미백제에 의한 영향에 대해 잘 알려져 있지 않은 상태이다. 이에 본 실험에서는 미백술을 시행한 법랑질 상에서 서로 다른 세 가지의 접착 시스템을 이용하여 미백술 후의 지연 시간이 결합력에 미치는 영향을 비교하고자 하였다. 발거한 대구치 68개를 물기가 있는 상태에서 근원심으로 절단하고 치관부를 자가중합 레진에 식립하여 시편을 제작하였다. 세 가지 접착제로 $One-step^{\circledR}$, Clearfil SE Bond $primer^{\circledR}$, One-up Bond $F^{\circledR}$를 이용하였다. 각 접착제를 미백을 시행하지 않는 대조군과 미백 시행 후 바로 접착한 즉시 접착군, 그리고 2주간 생리식염수에 보관한 후에 접착한 지연군으로 나누어 총 9개의 실험군으로 나누었다. 접착제를 처리한 면에 Clearfil $AP-X^{\circledR}$ 복합레진을 2mm충전하고, 40초간 광중합을 시행하였다. 24시간 후 전단접착강도를 측정하였으며, 그 결과는 다음과 같이 나타났다. $One-step^{\circledR}$의 경우, 즉시 접착군에서 지연 접착군보다 유의성 있게 낮은 접착강도를 나타내었다. Clearfil SE $Bond^{\circledR}$의 경우, 즉시 접착군과 미백을 시행하지 않은 군간에는 접착 강도에 유의한 차가 없었으나,지연접착군에서는 낮은 강도를 나타내었다. One-Up Bond F$^{\circledR}$의 경우, 즉시 접착군에서 유의성 있게 낮은 전단접착강도를 나타내었고, 전반적인 접착 강도가 다른 두 접착제에 비해서 유의성 있게 낮은 값을 보였다. $One-step^{\circledR}$을 사용할 경우 지연접착을 하는 것이 추천되며, Clearfil SE Bond$^{\circledR}$의 경우에는 즉시 접착을 시행하더라도 영향을 적게 받는 것으로 나타났으며, One-Up Bond $F^{\circledR}$의 경우 미백술 후 접착수복 과정에 사용에 제한이 있는 것으로 나타났다.

• Korean Journal of Social Welfare Studies
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• v.41 no.3
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• pp.349-378
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• 2010

The Life-Course perspective is a theoretical orientation that views the life-course as the age structure embedded in social institutions and history and understands the life-course of individual and group in the contextual perspective. The life-course perspective studies were developed in Germany and North America. They study social and historical effects and the effect of institutions and the state on the life-course, the pathway of the work career and differences of labour outcomes, and the inequality that is developed in the life-course. In Korea, the life-course perspective studies were tried in various fields and cumulated. However, it didn't established as a theoretical orientation. For applying the life-course perspective to connect the individual life-course with social and historical event, I describe the historical location of individuals born between 1930 and 1979 and analyse the change of their transitions to adulthood exploratorily. On results, the extension of education made the structural change of their life-course, and in young cohort the timing of leaving school, entering workforce, marriage and childbirth was delayed and transitions were made in narrower spread. It means the standardization of the life-course as appears in modern society. The 1970s birth cohort has the differenciated life-course pattern, however I cannot verify that change because of the right censoring.