• Geophysics and Geophysical Exploration
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• v.12 no.1
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• pp.33-40
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• 2009

In field surveys using the dipole-dipole electrical resistivity method, we often encounter negative apparent resistivity. The term 'negative apparent resistivity' refers to apparent resistivity values with the opposite sign to surrounding data in a pseudosection. Because these negative apparent resistivity values have been regarded as measurement errors, we have discarded the negative apparent resistivity data. Some people have even used negative apparent resistivity data in an inversion process, by taking absolute values of the data. Our field experiments lead us to believe that the main cause for negative apparent resistivity is neither measurement errors nor the influence of self potentials. Furthermore, we also believe that it is not caused by the effects of induced polarization. One possible cause for negative apparent resistivity is the subsurface geological structure. In this study, we provide some numerical examples showing that negative apparent resistivity can arise from geological structures. In numerical examples, we simulate field data using a 3D numerical modelling algorithm, and then extract 2D sections. Our numerical experiments demonstrate that the negative apparent resistivity can be caused by geological structures modelled by U-shaped and crescent-shaped conductive models. Negative apparent resistivity usually occurs when potentials increase with distance from the current electrodes. By plotting the voltage-electrode position curves, we could confirm that when the voltage curves intersect each other, negative apparent resistivity appears. These numerical examples suggest that when we observe negative apparent resistivity in field surveys, we should consider the possibility that the negative apparent resistivity has been caused by geological structure.

• Journal of Korean Ophthalmic Optics Society
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• v.2 no.1
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• pp.61-76
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• 1997

In this paper, we found out the objective refractive errors, the full corrective refractive powers, and the prescriptions for 64 males and 36 females aged 18 to 26 years. To increase the unaided visual acuity 0.1 to the aided visual acuity 1.0 with the glasses, we needed the spherical equivalent refractive power of -3.00D for male and -2.91D for female respectively. To increase the unaided visual acuity 0.5 to the aided visual acuity 1.0 with the glasses, we needed the spherical equivalent refractive power of -0.5D for male and -1.38D for female respectively. Comparing unaided visual acuity and corrective refractive power, the more one has refractive error the less one has unaided visual acuity but these are not linear relationships. Comparing objective refractive error figures, full corrective refractive power figures and prescriptions, objective refractive error figures are the hightest, followed by full corrective refractive power figures. Prescriptions compared with the other two are lower. The cylindrical refractive powers are less than -2.50D. In this study, with the rule astigmatism is dominant over against the rule astigmatism and oblique astigmatism. The accommodation measured by push up method is 6.75D~10.04D for male and 7.50D~9.60D for female respectively.

• 한국노년학
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• v.30 no.3
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• pp.843-853
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• 2010

The purpose of this study is to find out the characteristics of elderly pedestrian accidents and to suggest policy implications to enhance the level of elderly pedestrian safety. Although much efforts has made to enhance traffic safety environment, pedestrian traffic accidents among elderly population are not significantly decreased. This is mainly because current traffic safety measures do not much consider the characteristics of elderly pedestrians in the aspects of physical and psychological conditions. Main findings from vehicle-pedestrian traffic accident data and survey are as follows. First elderly pedestrians have high probability of traffic accident near crosswalks or cross streets rather than on crosswalk or cross streets. Second they need more green light time for crossing the streets. Third, they feel motor cycles running on the side walk and parked vehicles on the side walk are the most dangerous factors. Forth, general drivers do not have reasonable understanding for the walking behaviors of elderly pedestrians. Fifth, elderly pedestrians frequently need to rest while walking. Sixth, elderly people do not see clearly or understand traffic signs. Finally, many elderly pedestrians experience accidents or inconvenience while walking on the sidewalk.

• Proceedings of the KAIS Fall Conference
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• 2012.05a
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• pp.300-303
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• 2012

기존의 디지털미디어에 관한 논의들이 지나치게 디지털기술의 생산성과 효율성에만 주목하면서 긍정적인 면도 많지만 역으로 디지털 치매 등과 같은 문제점을 내포하고 있다. 다시 말해 스마트 폰 등에 저장되어 있는 전화번호 및 메모 등이 우리에게 편리함이라는 혜택을 주고는 있지만 반대로 조그마한 것이라도 쉽게 기억해 내지 못하는 역효과가 사회적 이슈로 대두되고 있다. 이를 위해 본 논문에서는 디지털미디어 이용자들의 위험성과 문제점 및 해결방안에 대한 의견 등 최근 가장 주목받는 미디어로서 대부분 디지털매체를 포괄하는 융합미디어이기 때문에 다양한 위험요인들이 집결되어있는 특징을 여러 디지털기기사용자를 분석대상으로 삼아 이러한 유형들에 대한 사례들 그리고 이러한 유형들에 대한 예방 및 사후대응방안에 대한 의견을 확인하고 이를 해결하기 위한 방안을 제시하고자 한다.

• Proceedings of the Korea Society for Simulation Conference
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• 2002.11a
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• pp.109-113
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• 2002

본 연구에서는 서로 다른 형태의 VR 디스플레이 장비인 가상워크벤치와 프로젝션 월을 연동한 이종협업 가상환경을 구축하고 이러한 환경에서 단일 빌딩을 모델링 하는 전과정을 입체적으로 시뮬레이션 할 수 있는 어플리케이션에 대하여 소개한다. 수평 형태의 가상워크벤치 상에서는 건축가와 일반 사용자 혹은 견습 디자이너가 함께 참여하여 빌딩의 형태 및 색상, 재질 등을 인터랙티브하게 변화시키면서 디자인 된 모델을 단계별로 입체 시뮬레이션 할 수 있도록 하였다. 대형의 스크린을 기반으로 하는 수직형 프로젝션 월에서는 디자인 된 빌딩의 입면도를 시뮬레이션하고 빌딩의 외부 및 주변 환경을 네비게이션 할 수 있도록 하여 동일한 모델을 서로 다른 시점에서 관찰하고 의견을 교환하여 이를 모델링에 반영할 수 있도록 하였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.3
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• pp.34-41
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• 2009

Recently, information-Ievel of the people has been increased with growing IT cutting-edge technology. There is a trend to combine these achievements with information-technology, ubiquitous technology, and mobile technology in the field of transportation. Along with this trend, a PDA-based traffic accident investigation device was developed. This paper established the evaluation method of feasibility test on the PDA device, and performed qualitative and quantitative evaluation as compared with the current practice (manual investigation). Test results showed that traffic accident investigation using the PDA device was faster and more convenient than manual investigation. It is expected that the reliability of accident investigation will be improved by applying this tool with minor modifications.

• The Korean Journal of Zoology
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• v.32 no.1
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• pp.22-33
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• 1989

Comparison of morphological characters and development of eggs and larvae of two bitterlings, Acheilognathus limbata and A. signifer from Korea were observed and discussed taxonomically. A. signifer differs from A. limbata by the color pattern of dorsal and anal fin ray of male, egg form and the length of ovipositor of female. Although two species are overlapping each other in some morphometric characters, there is a great difference between the two in the multivariate analysis of 15 morphological characters of five comparative populations. These results indicate that A. limbata and A. signifer are two independent allopatric sibling species in Korea.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.560-565
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• 2006

Sprinkler system is the most effective fire suppression with high confidence among active fire extinguishing systems. According to the installation of the related system on buildings, more separation area of fire protection can be considered to the fire protection design, and also lower differential pressure (12.5 Pascal) is permitted on lobby of fire escape stairs and emergency elevator (25 Pascal shall be considered for none sprinkler system) with economic factor. More details will be handled on the related studies.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.947-948
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• 2009

국가정보화사업 투자효율성 향상을 위해 투자관리 체계구축의 필요성이 증가하고 있다. 세계 경제상황 악화와 새 정부의 IT 패러다임 변화도 이런 요인의 하나로 작용하고 있다. 제한된 예산 범위 내에서 다양한 정보화 수요를 적절하게 충족시키기 위해서는 성과관리를 기반으로 한 미래지향적 정보화 투자가 요구된다. 공공부문 정보화 추진 시에 예산 사업 평가관리가 일체화 되지 못해 투자관리가 효율적이지 못한 면도 있다. 본고에서는 이러한 상황을 고려해 미국의 정보화투자관리체계(CPIC) 등 국내 외의 현황을 분석해 보고 한국의 실정에 맞는 투자관리 체계를 제시하고자 한다. 아울러 국가정보화사업의 현황분석을 통해서 현장의 업무 절차를 기초로 한 투자관리 프레임워크를 제시하고자 한다. 이 프레임워크를 활용하기 위해 필요한 제도개선 등 향후과제도 살피고자 한다. 이 결과는 공공부문에서 최적화된 정보화 재원 배분을 통해 정보화 효율성 및 투자 성과 제고를 지원하기 위한 틀로 활용될 수 있다. 국가 정보화 계획 집행 평가의 전 과정을 연계하는 추진체계 및 제도 확충으로 정보화사업의 유기적 성과관리 실현에도 기여할 것으로 기대한다.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.296-302
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• 2014

The foliage of variegated Solomon's seal is excellent in cut flower arrangements. However, it has a restricted marketing period because the harvesting is limited in spring and summer. The increased interest requires the year-round production, thus techniques for dormancy breaking and forcing without low temperature treatment is needed. Therefore, experiments were conducted to d etermine whether gibberellic acid (GA) could break dormancy in variegated Solomon's seal. Thes prouting of dormant bud did not occur throughout the experiment when $GA_3$ $400mg{\cdot}L^{-1}$ was applied to dormant rhizomes as a soil drench. However, when plants were treated with a GA drench after scratch with razor blade or were given direct injection of GA, percent sprouting was increased up to 100 or 83.3%, respectively. However, because treatments with razor or syringe may damage internal organs, we tested another method, scarifying the rhizomes with sodium hypochlorite (NaOCl). Rhizome scarification with 4% NaOCl for 6 or 24 hours followed by drench of $GA_3$ $400mg{\cdot}L^{-1}$ increased the dormancy breaking percentage to 70 or 86.7%, respectively. Moreover, scarified and GA-treated rhizomes produced more leaves than untreated or GA-soil drenched plants in the glasshouse. These results showed the possibility of year-round production of variegated Solomon's seal foliage with rhizome scarification and GA treatments.