• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
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• pp.46-51
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• 2000

Environmental quality regulations are used to establish the maximum permissible concentrations of heavy metals before a site can be deemed to be polluted or contaminated. This paper compares the results obtained by 0.IN HCl extraction and acid extraction method(HNO$_3$+HClO$_4$.HCl). The leaching efficiency of 0.1N HCl extraction is directly proportional to the final pH of leachate, due to the different solubilities of the heavy metals at different pH values, The severe differences between 0.1N HCl-extractable and total metal contents result mainly from the buffering effect of carbonates, present in sediment. samples. Application of sequential extraction experiments to some sediments collected from gully pot in Seoul illustrates a much stronger scavenging effect by Fe and Mn-hydroxides, carbonates and organic phases. As deduced from both sequential extraction and leaching experiments, the relative mobility of heavy metals is found to be: Mn>Zn>>Co>Cd>>Cu>Pb>Cr>Fe, in spite of large differences in heavy metal content and localization. Changes in the physicochemical environments (such as acidification) caused by a traffic accident may result in the severe environmental pollution of heavy metals of surrounding area( surface water and rivers).

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2004년도 춘계학술발표회
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• pp.13-18
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• 2004

최근 우리나라 연안해역은 선박교통 용량의 대형화로 해상교통이 폭주하고 있다. 이러한 교통혼잡은 연안해역에 대해 인명, 재산, 환경오염등의 심각한 해양사고를 야기한다. 본 연구에서는 우리나라 연안의 해양사고를 확률적으로 분석한다. 본 연구의 수행을 위해 해상교통 용량과 기상조건, 해양사고등의 다양한 연관성을 기반으로 원인을 분석하였다. 그리고 해양사고의 형태를 선박의 크기, 선령, 선종등 다양한 관점에서 분류하고 세부적으로 분석하였다.

• 게임&엔터테인먼트 논문지
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• 제2권1호
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• pp.8-16
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• 2006

인터넷에서 게임 트래픽과 같은 대용량 데이터의 부하를 분산하고 안정적인 전송을 위해 멀티캐스트 라우팅 프로토콜을 사용한다. 다양한 멀티캐스트 알고리즘 중 최근 CBT(Core Based Tree) 방식이 널리 사용되고 있으나 코어 라우터로 트래픽 집중되는 병목현상과 코어라우터의 위치에 따라 푸어 코어(Poor core)현상이 발생한다. 본 논문에서는 코어 라우터의 병목현상을 초래하는 링크 레이트(Link Rate)에 따라 코어 라우터의 상태를 SS(Steady State), NS(Normal State), BS(Bottleneck State)로 구분하였으며, 코어 라우터의 과부하에 따라 멀티캐스트 라우팅 전략을 CBT에서 Anycast로 전환하는 방식을 제안하였다. 온라인 게임에서 교환되는 주요 패킷의 크기에 준하여 두 가지 라우팅 방식을 비교하고 트래픽의 증가에 따라 Anycast 라우팅 방식의 성능개선을 보였다.

• Weed & Turfgrass Science
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• 제5권2호
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• pp.88-94
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• 2016

Vehicular traffic on turf results in loss of green cover due to direct tearing of shoots and indirect long-term soil compaction. Protection of turfgrass crowns from wear could increase the ability of turf to recover from heavy traffic. Plastic turfpavers have been installed in trafficked areas to reduce soil compaction and to protect turfgrass crowns from wear. The objectives of this study were to evaluate traffic performance of turfgrasses (Zoysia matrella and Axonopus compressus) and soil mixture (high, medium and low sand mix) combinations on turf-paver complex. The traffic performance of turf and recovery was evaluated based on percent green cover determined by digital image analysis and spectral reflectance responses by NDVI-meter. Bulk density cores indicated significant increase in soil compaction from medium and low sand mixtures compared to high sand mixture. Higher reduction of percent green cover was observed from A. compressus (30-40%) than Z. matrella (10-20%) across soil mixtures. Both turf species displayed higher wear tolerance when established on higher sand (>50% sand) than low sand mixture. Positive turf recovery was also supported by complementary spectral responses. Establishment of Zoysia matrella turf on turfpaver complex using high sand mixture will result in improved wear tolerance.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제2권10호
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• pp.421-426
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• 2013

인터넷을 통해 전송되는 트래픽의 양이 점점 더 많아지고 있고, 이에 따라 트래픽의 양을 알아내는 것이 중요해지고 있다. 트래픽을 측정하는 기법에 대한 많은 연구가 있었으며, 주로 적은 양의 메모리를 사용해서 측정의 정확도를 높이는 방향으로 연구가 진행되고 있다. 이 논문에서는 기존 기법들에서는 제공하지 않는 플로우 라벨링 기법을 제안한다. 이 기법을 통해서 관리자는 특정 값 이상의 트래픽을 생성한 플로우의 라벨을 실시간으로 알아낼 수 있으며, 기존의 기법이 가지는 카운팅의 상한선을 확장시킬 수 있다. 가장 최근에 발표된 CSM (Counter Sharing Method)에 이 기법을 적용하고, CAIDA 데이터셋을 이용해서 성능을 분석해 본다.

• 한국컴퓨터정보학회논문지
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• 제14권10호
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• pp.259-270
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• 2009

본 연구의 목적은 통합도로교통 서비스 체계 구현을 위한 교통정보센터를 구축하는데 있다. 이러한 목적을 달성하기 위하여 기존의 교통정보센터 기능과 운영현황을 분석하고, 통합도로교통정보 서비스를 제공하는 교통정보센터를 개발함으로서 안전지향형 통합도로교통정보센터의 구현사례를 소개한다. 지능형교통체계는 안전지향의 통합도로교통정보 서비스 제공을 통한 교통안전체계를 구현할 뿐 만 아니라 전방의 홍수, 폭설 낙석, 도로유실 붕괴 등과 같은 자연재해 및 긴급상황 발생시 관련 정보를 시의 적절하게 제공함으로써 운전자의 안전한 도로운행을 지원하게 된다. 따라서 통합도로교통정보 서비스체계의 교통정보센터는 국민들에게 편리하게 사용할 수 있는 대국민 교통정보 서비스 제공으로 이용자 친화형 교통관리체계와 통합도로교통정보센터 기능을 실현하는데 일조할 것이다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.222-229
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• 2000

Malty bridges are severely damaged by the overloaded heavy vehicle and tile trend will become more serious because the traffic volume is continuously increasing. Currently, the vehicles with gross weights over 40 tons or axle weight over 10 tons are not allowed on the public road. However, this regulation is not based on a systemetic study on the bridge capacityand assumed to be much too conservative depending on the vehicle types ans bridge types. In this study, the permit weights of heavy vehicles of diverse axle spacings and axle load distribution are calculated considering the structural characteristics of bridge superstructures. In order to consider the various load effects of heavy weight vehicle crossings, three conditions are considered in the calculation of permit vehicle load. From the results, the permit vehicle weights of bridges are calculated and simplified formulas which can be used in the case when only the vehicle dimension are known are presented.

• The Korean Journal of Ecology
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• 제18권2호
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• pp.285-293
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• 1995

The relationships among the contents of Pb, Zn, Cd, Cu and microbial biomass and activity of soil were investigated in Kyongbu, Yongdong, and Chungbu highways. The heavy metal concentrations were the highest in Kyongbu highway with high traffic density. The levels of these metals in soil in three highway sites were much higher than Mt. Kwank as control site. The highest concentrations of heavy metals were found in the upper layer of soil adjacent to the roadside. Dehydrogenase activity (DHA) and adenosine tri-phosphate (ATP) contents were generally lowest at distance of 0.5 m from the roadside. Simple regression analysis indicated that DHA and ATP contents were highly negatively correlated with Pb and Zn concentrations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.70-71
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• 2006

IEC61850 which has comes to international standard for substation automation is designed with a station and process bus communication with Ethernet. In this paper, mentioning difference between official networks and substation networks, authors present the requirements for temperature, humidity and EMI characteristics. The properties which network switch should be satisfied and the technologies which make those requirements possible are also proposed. Additionally, we analysis the traffic pattern of communication services which IEC61850 supports. Based on the pattern, we propose a practical design example of IEC61850 based network for a 154kV substation.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.129-135
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• 2000

Four types of land use were selected for sampling and study with different characteristics of heavy metal contamination during the period from August 1998 to June 2000. A series of studies have been carried out concerning the physicochemical characteristics of the sediments settling down in a gully pot to evaluate the contamination of Pb, Zn, Cd, Co, Cr and Cu. An examination of six elements indicated that Zn, Cu and Pb were the heavy metals severely impacted by anthropogenic input in Seoul. An assessment of 60 volatile organic compounds (VOCs) in urban runoff and ground water was conducted based on samples collected from 31 sites and 12 wells, respectively, in Seoul City. The higher levels of alkyl benzenes in urban runoff indicated that Seoul areas were mainly contaminated through traffic sources.