• Journal of the Korean Society for Railway
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• v.12 no.6
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• pp.983-988
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• 2009

When the railway vehicle passing through curves & transitions, the running speed must improve by proposing the practical standard about maximum running possibility speed of each section on existing line considering running safety. In this paper, when the railway vehicle passing through curves of actual track conditions (Namsunghyun-Chungdo up & down lines), the effect that has influence on running safety is examined to devise the high speed of vehicle which passing through curves which risk of derailment is high. The running safety analysis is performed that running speed by curve radius improves 5-20% compared with existing speed under actual track conditions. In result of the running safety analysis, in case the speed condition is fewer than 15% compared with existing speed, the derailment coefficient and unloading ratio are within acceptable level. so we could confirm possibility of speed improvement on the whole Namsunghyun-Chungdo up & down lines.

• Journal of the Korean Society for Railway
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• v.14 no.3
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• pp.234-239
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• 2011

Installing the temporary bridge after excavating the railway requires installing movable cross beam, but as it doesn't requires isolating the catenary or cutting the rail, it's applicable to double-track with frequent operation. In this study, a displacement meter was placed on temporary bridge to monitor the displacement pattern in curve section (R400) completed using temporary bridge method, and wheel load, lateral pressure and derailment coefficient were measured to evaluate the load imposed on track and the stability in curve section (R400) for quantitative evaluation of training running safety. As a result of the measurement, when trains passing over a temporary bridge, the maximum value of Wheel load and Lateral Force is analyzed as the 51% and 81% of standard level according to foreign country's performance tests, There is no trouble with stability analysis in Wheel load and Lateral Force occurring. Additionally, Wheel load and Lateral Force considered as the safety standard are tested 49% of limiting value regardless of trains, which the norm value quite well, there is no problem with train running.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.3
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• pp.221-228
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• 2007

Quantitative analysis of distribution characteristics of soils in Jeju Island was conducted by using geographic information system (GIS) technology. Soil series could be classified 5 groups after cluster analysis with proximity ratios among soil series which mean ratios of boundary lengths of other soils to total boundary length. Classification with proximity only was similar to conventional classification system at detailed soil map although conventional system was made from several criteria such as soil color, altitude and chemical characteristics of soils. Altitudinal sequence of soil series was also suggested from representative altitudes of them which could be found from areal distribution curve along altitudes. The sequence was brown forest soils - black soils - very dark brown soils - dark brown soils from the peak of Halla Mt. to the coast on all sides, which maybe related to pedogenesis process in Jeju Island.

• Analyses & Alternatives
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• v.6 no.1
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• pp.7-33
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• 2022

This study analyzes the difference in the awareness of Korean Unification among age groups based on survey data. It is verified by statistical model analyses that the ratio of agreement for Korean Unification increases with the age growth, but after the highest peak at the age group of 44 ~ 53 years, the ratio of agreement gradually decreases. The statistical model shows that the age group of 44 ~ 53 years old has 2.5 times higher odds of agreement than the age group of 24 ~ 33 years old and the odds of female to male is 0.56. Meanwhile, the ratio of increase in the agreement, aligned with the increasing age groups, shows 4.3 times higher for males than females. The difference in the ratio of agreement in the overall age groups is estimated to be contributed the most by the significant difference in the ratio of agreement for Korean Unification between the young male generation (in their 20s and 30s) and the middle-aged male generation (in their 40s and 50s).

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.362-362
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• 2021

섬진강은 하굿둑이 없는 열린 하구로서 하구로부터 약 21km까지 조석의 영향을 받아 강물의 염도가 시간에 따라 변하는 환경이다. 오랫동안 섬진강 하구는 다양한 원인으로부터 바다화로 대표되는 염하구 문제가 지역 현안 사항으로 제기되어 왔다. 상류에서의 용수사용 증가로 인한 하천유하량 감소 또한 그 원인들 중 하나로 판단됨에 따라 실제 하구까지 내려오는 하천유량과 바다로부터 유입되는 해수를 구분하여 정량화하는 연구가 필요한 사안이다. 본 연구의 목적은 섬진강수계 하구에서의 다양한 생태환경을 보전하기 위한 적정 염분유지가 요구됨에 따라 염분과 유하량(하천유량)의 관계 규명과 기준을 마련하고자 한다. 섬진강수계 하류지역 주민의 민원과 갈수기 하천유량 부족으로 적정 하천관리를 위해서 2020년 이후로 섬진강수계 주요 댐에 대한 과거 20년간 용수공급 현황과 빈도별 유입량을 고려한 용수공급기준선과 하천유지용수 개념의 환경대응용수 공급량을 산정하였으며, 댐 용수공급의 안정성이 확보된 상황에서의 환경대응용수를 공급 중이다. 또한, 상류 유하량과 바다 조위에 따른 염도의 상관성을 규명하기 위해서 섬진강 하구의 염도(섬진교, 섬진강대교) 계측기를 설치하여 모니터링을 실시하여 측정된 자료를 이용하여 하천관리방안을 마련하고자 한다. 최종적으로, 최근까지의 실측 모니터링 자료를 이용한 유량-조위-염분 상관관계 분석을 통한 의사결정표(조견표) 산정하고 실제 댐운영('20.4.~현재) 및 하천유량 모니터링('20.4.~현재) 자료를 이용한 하천유량확보 효과 분석을 실시하여 섬진강 하구의 통합관리(수량-수질)를 위한 기준을 설정하여 향 후 섬진강수계 통합물관리 업무와 갈수 및 가뭄시기에 적정한 하천관리를 위한 실증적인 방안을 검토하여 제시하고자 한다.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2002.05a
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• pp.35-39
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• 2002

광고성 메일이 개인 당 하루 평균 10통 내외로 오며, 그 제목만으로는 광고메일을 효율적으로 제거하기 어려운 현실이다. 이러한 어려움은 주로 광고 제목을 교묘히 인사말이나 답신처럼 변경하는 데에서 오는 것이며, 이처럼 제목으로 광고를 삭제할 수 없도록 은폐하는 노력은 계속될 추세이다. 그래서 제목을 통한 변화에 적응하면서, 제목뿐만 아니라 내용에 대한 의미 파악을 자동으로 수행하여 스팸 메일을 차단하는 방법이 필요하다. 본 연구에서는 정상 메일과 스팸 메일의 범주화(classification) 방식으로 접근하였다. 이러한 범주화 방식에 대한 기준을 자동으로 알기 위해서는 사람처럼 문장 해독을 통한 의미파악이 필요하지만, 기계가 문장 해독을 통해서 의미파악을 하는 비용이 막대하므로, 의미파악을 단어수준 등에서 효율적으로 대신하는 text mining과 web contents mining 기법들에 대한 적용 및 비교 연구를 수행하였다. 약 500 통에 달하는 광고메일을 표본으로 하였으며, 정상적인 편지군(500 통)에 대해서 동일한 기법을 적용시켜 false alarm도 측정하였다. 비교 연구 결과에 의하면, 메일 패턴의 가변성이 너무 커서 wrapper generation 방법으로는 해결하기 힘들었고, association rule analysis와 link analysis 기법이 보다 우수한 것으로 평가되었다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.461-464
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• 2008

This study is compactability and Passing ability to get to know the flowing characteristic of high flowing self-compacting concrete with mixing steel fiber of various size and diameter. After flowing test, size and diameter are getting longer, flowing performance is getting lower. It meets the standard of combined high flowing self-compacting concrete of JSCE 2 grade and passing performance from ASTM C 1621. Through this study, it can be possible to be applied in site of HSCC with mixing steel fiber.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.273-276
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• 2003

본 논문에서는 한쪽이 단락된 스트립선로(Stripline)와 Loading 캐패시턴스(Capacitance)로 구성된 새로운 형태의 1/4파장 스트립선로 공진기를 제안하였으며, 이 공진기를 이용해서 5.2 GHz 대역 무선 LAN용 적층 대역통과 여파기를 설계, 제작 하였다. 제안한 공진기의 전파지연효과(Slow-wave Effect) 때문에, 기존의 공진기에 비해서 길이가 축소되며, 기준 공진주파수(Fundamental Resonant Frequency)에 대한, 첫 번째 기생공진주파수(First Spurious Resonant Frequency) 값이 커지기 때문에, 넓은 상향저지대역(Wide Upper Stopband)을 갖는 초소형의 대역통과 여파기의 설계가 가능하다. 설계한 여파기를 LTCC 적층 공정 기술을 이용하여 제작하였으며 그 크기는 $3.2mm{\times}1.6mm{\times}0.8mm$ 이다.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.2
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• pp.75-111
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• 2020

The civilian drone world has evolved in recent years from one dominated by hobbyists to growing involvement by companies seeking to profit from unmanned flight in everything from infrastructure inspections to drone deliveries that are already subject to regulations. Drone flight under the property right relation with the land owner would be deemed legal on the condition that expeditious and innocent passage of drone flight over the land be assured. The United Nations Convention on the Law of the Sea (UNCLOS) enshrines the concept of innocent passage through a coastal state's territorial sea. Passage is innocent so long as it is not prejudicial to the peace, good order or security of the coastal state. A vessel in innocent passage may traverse the coastal state's territorial sea continuously and expeditiously, not stopping or anchoring except in force majeure situations. However, the disturbances caused by drone flight may be removed, which is defined as infringement against the constitutional interest of personal rights. For example, aggressive infringement against privacy and personal freedom may be committed by drone more easily than ever before, and than other means. The cost-benefit analysis, however, has been recognjzed as effective criteria regarding the removal of disturbances or injunction decision. Applying that analysis, the civil action against such infringement may not find suitable basis for making a good case. Because the removal of such infringement through civil actions may result in only the deletion of journal article. The injunction of drone flight before taking the information would not be obtainable through civil action, Therefore, more detailed and meticulous regulation and criteria in public law domain may be preferable than civil action, at present time. It may be suitable for legal stability and drone industry to set up the detailed public regulations restricting the free flight of drone capable of acquiring visual information amounting to the infrigement against the right of personal information security.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1258-1263
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• 2011

This study was conducted to reclassify Asan series based on the second edition of Soil Taxonomy and to discuss the formation of Asan series distributed on the rolling to hilly areas. Morphological properties of typifying pedon of Asan series were investigated and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon of Asan series has dark yellowish brown (10YR 4/4) gravelly loam Ap horizon (0-18 cm), strong brown (7.5YR 5/6) gravelly clay loam BA horizon (18-30 cm), red (2.5YR 4/6) gravelly clay loam Bt1 horizon (30-52 cm), red (2.5YR 4/8) gravelly clay loam Bt2 horizon (52-98 cm), and red (2.5YR 4/8) gravelly clay loam C horizon (98-160 cm). The typifying pedon has an argillic horizon from a depth of 30 to 98 cm and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. It can be classified as Ultisol, not as Inceptisol. It has udic soil moisture regime, and can be classified as Udult. Also that meets the requirements of Typic Hapludults. It has 18-35% clay at the particle-size control section, and has mesic soil temperature regime. Therefore Asan series can be classified as fine loamy, mesic family of Typic Hapludults, not as fine loamy, mesic family of Typic Dystrudepts. Asan series occur on rolling to hilly areas in residual materials derived from granite gneiss, schist, and gneiss rocks. They are developed as Ultisols with clay mineral weathering, translocation of clays to accumulate in an argillic horizon, and leaching of base-forming cations from the profile for relatively long periods under humid and temperate climates in Korea.