• 대한전자공학회논문지TC
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• 제42권6호
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• pp.9-16
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• 2005

본 논문에서는 액세스 망 인터페이스로 EPON 정합을 기본으로 하는 홈 네트워크에서 방송 서비스와 IP 데이터 서비스를 융합하는 것에 초점을 두고자 한다. 본 논문에서는 액세스 망에서는 오버레이 전송 방법을 이용하고 홈 네트워크에서는 멀티캐스트 그룹 관리 프로토콜인 IGMP와 IGMP 스누핑 기능을 이용함으로써 액세스 망에서뿐만 아니라 댁내에서도 방송 서비스와 데이터 서비스를 융합시킬 수 있는 새로운 구조를 제안한다. 또한, 홈 게이트웨이를 통해 댁내 방송 서비스를 지원하기 위한 일련의 방법 및 절차에 대하여 설명한다. 본 논문에서 제안하고자 하는 방법은 다음의 3 가지로 구성되어 있다. I) 방송신호와 인터넷 데이터의 오버레이 전송 모델, ii) 다중 튜너 시스템을 이용하는 튜너/변화 모듈에서 특정 방송 채널을 선택하고 선택된 방송 스트림을 IP 멀티캐스트 패킷으로의 변환, iii) 변환된 IP 멀티캐스트 패킷을 L2 이더넷 홈 게이트웨이의 코어 모듈인 L2 이더넷 스위치로 보내고 IGMP 스누핑 기능을 이용하여 L2 멀티캐스트 처리 방법에 의하여 목적지 포트로의 전송.

• 농업과학연구
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• 제43권2호
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• pp.215-220
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• 2016

The global cultivation area of genetically modified crops (GM crops) has been increasing every year. Cultivation of GM crops is not only beneficial to the economy but also has positive effects on the environment in decreasing the use of agrochemicals, chemical fertilizers, and agricultural machinery. However, there have been controversies about the admixture of GM crops and non-GM crops and the unintentional release of GM crops to the environment. Especially in Korea, where consumption of agricultural products is import-dependent, the economic importance of GM crops has been a significant issue. The Act on import and distribution of GM crops was established in 2001 to start the management of GM crops in Korea. Recently, the imported amount of GM crops to Korea has reached over 10 million tons and is increasing very rapidly; consequently, the potential environmental impact of GM crops is becoming a big issue in Korea. In Japan, the discovery of imported GM canola plants around ports in 2005 raised awareness of the unintentional release of GM crops. In Korea, GM maize plants were also found in port and feed factory surroundings from 2005 to 2007. It is now necessary to monitor imported GM crops by tracing distribution, transport process for practical environmental risk assessment. Possible gene transfer from GM crops to non-GM crops should also be investigated in the cultivation area and the surroundings as well.

• 산업경영시스템학회지
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• 제39권2호
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• pp.19-27
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• 2016

Maritime transport is now regarded as one of the main contributors to global climate change by virtue of its $CO_2$ emissions. Meanwhile, slow steaming, i.e., slower ship speed, has become a common practice in the maritime industry so as to lower $CO_2$ emissions and reduce bunker fuel consumption. The practice raised various operational decision issues in terms of shipping companies: how much ship speed is, how much to bunker the fuel, and at which port to bunker. In this context, this study addresses an operation problem in a shipping companies, which is the problem of determining the ship speed, bunkering ports, and bunkering amount at the ports over a given ship route to minimize the bunker fuel and ship time costs as well as the carbon tax which is a regulatory measure aiming at reducing $CO_2$ emissions. The ship time cost is included in the problem because slow steaming increases transit times, which implies increased in-transit inventory costs in terms of shippers. We formulate the problem as a nonlinear lot-sizing model and suggest a Lagrangian heuristic to solve the problem. The performance of the heuristic algorithm is evaluated using the data obtained from reliable sources. Although the problem is an operational problem, the heuristic algorithm is used to address various strategic issues facing shipping companies, including the effects of bunker prices, carbon taxes, and ship time costs on the ship speed, bunkering amount and number of bunkering ports. For this, we conduct sensitivity analyses of these factors and finally discuss study findings.

• 한국통신학회논문지
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• 제37권6B호
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• pp.433-442
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• 2012

We have proposed a solution to multicast services and an advanced quality of service (QoS) mechanism on a packet transport system (PTS) based on PBB-TE. The point-to-multipoint (PtMP) connection in the PBB-TE system have been realized by grouping point-to-point (PtP) PTL trunks and mapping a BSI onto the PtP PTL trunks using a multicast backbone destination address. To provide end-to-end QoS of the PtMP services, the hierarchical QoS scheme for backbone service instances and connection-oriented paths has been implemented in the PTS. For providing different capabilities for service selection and priority selection, the PTS offers to customers three basic types of the port-based, C-tagged, and S-tagged service interface defined by the IEEE 802.1ah. To offer to customers different capabilities of the layer 3 applications and services, moreover, an IP-flow service interface have been added. In order to evaluate traffic performance for PtMP services in the PTS, the PtMP throughputs for the link capacity of 1 Gbps at the four service interfaces were measured in the leaves of the ingress edge node, the transit node, and the egress edge node. The throughputs were about 96 % because the B-MAC overhead of 22 bytes occupies 4% of the 512-byte packet. The QoS performance is ability to guarantee an application or a user a required bandwidth, and could be evaluated by the accuracy of policing or shaping. The accuracy of the policing scheme and the accuracy of the shaping scheme were 99% and 99.3% respectively.

• 대한교통학회지
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• 제24권4호
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• pp.67-79
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• 2006

철도소화물사업은 도로발달, 택배사업 활성화로 1990년 2,520만개를 정점으로 취급물량이 최근 10년간 연평균 10%이상 급속히 감소하였으며. 취급역도 '73년 421개역에서 현재 90개역만 남아있는 상황이다. 경영성적 측면에서 보면 '88년 이후부터 위탁수수료 지급이 운송수입보다 많아 $'99{\sim}'03$년 동안 연평균 52억원의 적자('04년 49억)를 기록하였으며, 인건비, 유지관리비 등을 포함하는 원가기준으로는 2004년도에 464억원의 적자를 기록한 바 있다. 이에 따라, 2005년 1월 1일 철도청의 공사화 이후 효율성 제고 차원에서 철도소화물사업의 축소 폐지가 제기되고 있어 본 사업에 대한 깊이 있는 연구가 시급한 실정이다. 본 연구에서는 철도소화물사업의 문제점과 택배와의 경쟁력분석을 통한 철도소화물사업의 장래전망을 수행하였으며, 본 사업의 폐지방안과 폐지효과를 제시하였다.

• 수산해양교육연구
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• 제9권1호
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• pp.49-56
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• 1997

It is the developing policy of fishing village of korea that the fishermen are not to leave their fishing village by the construction of abandant and rich fishing village in the social, cultural and economic side of view. The government has promoted the project to improve the fishing and agrarian village from 1992 year, but it is not so helpful to solve the problem of the island and fishing village. Therefore, it has to improve the structure of fishing village and to develope the vital and lively fishing village, Japan had enacted the special law for the promotion of out-island which was called the law for the promotion of Ri-do isalnd, and commenced to develop the Ri-do island. The law for the promotion of Ri-do island is limited to 10 years, but it was amended 10 times and Japanese government has invested as many as budget to Ri-do isalnd during 30 years. Korean government also had enacted and enforced the special law for the promotion of out-isalnd developement referring to Japanese system. However, it is neccessary at first to improve the system that the fishing village is able to develope the fishing port in order to make higher the efficiency of investment. Moverover, the earning differentials bewteen the city and the fishing village has to decrease by the developement of transport convenience and pavement of the road of the out-isalnd and remote fishing village. Otherwise, it is requested rapidily to set up the welfare policy for the aged people because the inhabitants of fishing village become to great age, and inhabitants could be at least diagnose one time every week in the good medical facilities. The ministry of marine and fisheries has to permit the sports fishing business by the small fishing vessel in order to increase the income of inhabitants of fishing village and put a lot of the fishing reefs which are constructed to 2-3 story into the sea. And then the sports fishing business will be flourish by the small fishing vessel.

• 디지털융복합연구
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• 제10권11호
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• pp.197-202
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• 2012

내륙물류의 생산성 향상 및 친환경적 체계 구축을 위해 많은 국가에서 블록 트레인 서비스(Block Train Service) 연구가 활발히 진행되고 있다. 하지만 철도부문의 정부 독점 운영 상황과 대부분의 물류정보가 기업의 영업기밀에 속하는 물류산업의 특성 등으로 인해 BT 서비스에 대한 일반의 이해와 연구적 접근이 쉽지 않다. 이에 본 연구에서는 BT 운용에 필요한 학습 및 전략적 판단을 지원하는 BTS 시뮬레이터를 개발하였다. 이를 위해 국내 대표 BT 운영사인 K사의 실무자들을 대상으로 심층 인터뷰와 관련 자료의 분석을 진행하였다. 본 시뮬레이터는 K사의 부산신항-의왕 구간 사례를 참조하였으며, BT 운영에 관한 시나리오 생성 및 분석 기능을 지원한다. 본 연구는 새로운 형태의 BT운영 학습 및 전략 분석 지원 기술을 연구하였다는 데 의의가 있다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.273-273
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• 2002

Masan barber was situated in S.Korean southern central coast. And it is contributing greatly in S.korea's economy development to international trading port of Heaven's blessing that possess natural, geographical situation. Also, because there are Masan free tax area and chanwon heavy industrial complex, sachon air industrial complex etc. on back, it is important permanency in our country. Specially, because inland transport routes such as southern highway, Guma highway and national road system are developed well, the importance is very high. Masan harbor 1899.05.01 be that opened, the 1st and 2nd (central pier) was build 1938∼1944 year, and the 3rd pier was 1973∼1978 year. the 4th pier was 1974∼1983 year, 5th pier was 1984∼1988, 6th pier (west pier) was 1985∼1992 year. it was developed over 100 years. But, it did great many harbor and bay development of last 100 yens but research about coastline change and seashore reclamation is insufficient. Therefore, this research executed research about coastline change of Masan bay of last 100 years, In this study, we analyzed aerial photographs and tide data for the past 100 years using digital aerial photo analysis and GIS techniques for each 3-year interval. We abstracted beach DEM (digital elevation model) and ortho aerial photographs, and conducted a space analysis. As a result, we were able to identify changes in the area As a result, we drew 10 years cycle coastline change of Masan bay. and we can detect bay coastal line change and calculate refill rate.

• 한국컴퓨터정보학회논문지
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• 제20권1호
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• pp.237-246
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• 2015

본 논문에서는 컨테이너터미널에서 탠덤 리프트 안벽크레인과 고생산성 컨테이너 이송차량 Alternative ship-to-yard vehicles를 고려한 시뮬레이션을 활용하여 컨테이너터미널의 생산성 향상 모델을 제안한다. 이 방법의 특징은 탠덤 리프트 안벽크레인과 고생산성 컨테이너 이송차량의 데이터를 도출하고, 회귀분석 함으로써 탠덤 리프트 안벽크레인의 생산성 모델을 추정한다. 탠덤 리프트 안벽크레인은 한 사이클 당 20ft 컨테이너 4개, 40ft 컨테이너 2개를 동시에 취급함으로서 기존의 싱글 안벽크레인보다 이론상 약 2배의 컨테이너 생산성을 증가시키는 장비이고 Alternative ship-to-yard vehicles는 기존의 야드 트랙터보다 더 많은 최대 4TEU의 컨테이너를 운반시킬 수 있는 장비이다. 본 논문에서는 신기술 안벽장비인 탠덤 리프트 안벽크레인과 신기술 이송장비인 Alternative ship-to-yard vehicles를 적용한 시뮬레이션을 통하여 생산성에 관한 데이터를 도출하고 통계 기법인 회귀분석을 통하여 컨테이너 터미널의 생산성의 추정모델을 구해보고자 한다.

• 전기전자학회논문지
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• 제26권3호
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• pp.396-400
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• 2022

본 연구에서는 해저에서 발견한 인체를 해수면까지 운반하는 인양백을 기반으로 수중구조를 위한 ICT 기반 수중통신 모니터링 장치를 구현한다. 인양백은 에어를 주입하는 리프트백, 사이드백, CO₂ 카트리지 등으로 패키지화 되어 있다. 모니터링 시스템은 휴대하기 용이한 구조로 모바일 방식으로 개발한다. 수중 초음파 센서 신호는 USB 포트를 사용하여 공급되며, O/S는 리눅스로 구성한다. 수중통신동시험은 동해안에서 수심 6m~40m까지 실시간으로 측정 시험을 진행한다. 초음파 음향센서는 2,400bps로 변환되어 2원화에 따라 전송오차를 검증한다. 센서에서 모니터링까지 통신속도는 115,200bps, 제어기에서 수신부까지 통신속도는 2,400bps를 사용한다. 리프팅 장치의 상용화 단계에서 로우엔드 타입 개발이 용이하고 호환성이 넓도록 한다.