• Journal of Positioning, Navigation, and Timing
• /
• 제12권3호
• /
• pp.281-288
• /
• 2023

The International Maritime Organization (IMO) states that the recommended horizontal accuracy for coastal and offshore areas is 10 m, the Alert Limit (AL) is 25 m, the time to alert is 10 seconds, and the integrity risk (IR) is 10^-5 per three hours. For operations requiring high accuracy, such as tugs and pushers, icebreakers, and automated docking, the IMO dictates that a high level of positioning accuracy of less than one meter and a protection level of 0.25 meters (for automated docking) to 2.5 meters should be achieved. In this paper, we analyze a method of calculating the user-side protection level of the centimeter-level precision Global Navigation Satellite System (GNSS) that is being studied to provide augmentation information for the precision Positioning, Navigation and Timing (PNT) service. In addition, we analyze standardized integrity forms based on RTCM SC-134 to propose an integrity information form and generate a centimeter-level precise PNT service plan.

• 산업공학
• /
• 제24권2호
• /
• pp.164-172
• /
• 2011

H maritime company in Korea had a long history of difficulty in obtaining enough empty containers to transport its commodities. Despite efforts to resolve the problem, the repositioning of empty containers between depots was still planned manually, which consumed much worker time. To automate the generation of reposition plans, we developed a planning system to optimize the company's reposition of empty containers between global depots with a linear programming model functioning as a key decision engine in the system. The model determines the route, volume and mode of transportation for repositioning empty containers from depots with surplus containers to those requiring containers, as well as the empty space of ships generated from the unloading or loading of full and empty containers. The system has been in operation in the company's global network since March 2008.

• 한국정밀공학회지
• /
• 제17권11호
• /
• pp.101-107
• /
• 2000

A design of the global optimal sliding mode control is presented to control the second order uncertain time varying system with torque limit. With specified ranges of parametric uncertainties and torque limit, the minimum arrival time to reference inputs can be calculated. The proposed control scheme is applied to the motor system carrying loads. The merit of the proposed control scheme is that the arriving time at the reference input, which is the revolution angle, and the maximum allowable acceleration are expressed in a closed form solution. The superior performance of the proposed control scheme is validated by the computer simulation and experiments comparing with other sliding mode controllers.

• 해양환경안전학회:학술대회논문집
• /
• 해양환경안전학회 2017년도 공동학술발표회
• /
• pp.85-85
• /
• 2017

• 한국항해항만학회지
• /
• 제46권3호
• /
• pp.216-226
• /
• 2022

세계 주요 글로벌 해운·항만의 산업 트랜드는 COVID-19 바이러스 확산, 글로벌 기업들의 GVC 재편, IMO의 환경규제 강화 등으로 인해 급속도로 변화하고 있다. 이러한 환경변화 속에서 부산항은 2013년 글로벌 컨테이너 항만순위 5위였으나 2014년 닝보-저우산에 밀려 세계 6위로 떨어졌다. 그리고 COVID-19 바이러스가 발생한 이후 2020년 부산항의 글로벌 컨테이너 항만순위는 Qingdao항에 밀려 7위로 떨어졌다. 포스트 코로나 시대 부산항이 글로벌 컨테이너 항만들과 경쟁하여 항만 경쟁우위를 점하기 위해서는 부산항의 경쟁력 요인을 정확하게 파악하고 종합적인 정책을 수립할 필요가 있다. 이에 본 연구는 2005년에 진행된 1차 연구와 비교하여 현재 글로벌 선사들이 항만을 선택하는데 있어 부산항의 경쟁력 요인이 어떻게 변화하였는지 분석하고자 하였다. 또한, 향후 기항빈도와 성장가능성에 영향을 주는 요인을 단계적 다중회귀분석으로 파악하여 종합적인 정책방안을 수립하였다. 분석결과 포스트 코로나 시대 부산항의 기항선호도와 성장가능성에 가장 큰 영향을 주는 요인은 '항만시설'로 나타났으며, 향후 기항빈도는 '지정학적 위치' 요인에 가장 큰 영향을 받는 것으로 나타났다.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2021년도 추계학술대회
• /
• pp.119-120
• /
• 2021

국내 어선의 해상업무용 무선설비 및 항해 장비는 IEC 60945를 준용한 KN60945_60533의 성능기준을 따르도록 규정하고 있다. LTE-M 송수신기는 해상업무용 무선설비에 포함되지 않아 기존 선박용 장비들과 동일한 기준을 적용받지 않기 때문에, 방사 방출 또는 전도 방출에 의한 간섭으로 기존 해상업무용 무선설비에 가청 소음을 발생하는 원인이 되고 있다. 본 논문에서는 초고속해상무선통신망 무선설비를 소형선으로 확대보급하기 위해 선결 사항으로 위와 같은 간섭 영향의 원인을 분석하고 관련 대책을 검증 제안한다.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2015년도 춘계학술대회
• /
• pp.203-204
• /
• 2015

This study examines the view of global trends in the Arctic Shipping. It is also provides a framework for understanding how participated in Arctic. The trends that had made it a centre of global attention. Surge of interest in its economy and politics has increased. That surge was driven by three things. Political and business agreements in the Arctic and with Arctic states, a trend that is likely to continue as the Arctic warms.

• 해양환경안전학회지
• /
• 제28권3호
• /
• pp.430-440
• /
• 2022

Shipping companies are key components of the logistics industry, which is extremely significant in enhancing the country's comprehensive national power and promoting global trade development. In the context of the implementation of the new development pattern strategy in China and the impact of the global novel coronavirus (COVID-19), this paper takes 22 Chinese shipping listed companies as the research object and analyses the operational efficiency of them from 2011 to 2020 based on the Super-SBM DEA Model and Window DEA Model. Factors affecting the efficiency are further analyzed with the Tobit model. The research conclude that the operational efficiency of Chinese shipping companies as a whole shows a steady increase from 2011 to 2020. Although most of them are in a relatively ef ective operation state, fewer are absolutely effective companies. Besides efficiency among companies differs obviously, which indicates the potential of further improvement and promotion. What's more, factors such as current economic development level, enterprise size, human resources quality and enterprise turnover speed have significant positive correlation to the operation efficiency of Chinese shipping listed companies, which is significant to improve the operation efficiency of Chinese shipping companies.

• Strategy21
• /
• 통권30호
• /
• pp.200-235
• /
• 2012

Over the past few years, due to the climate change of the earth, the Arctic's sea ice cover is undergoing a historic transformation - thinning, extent reduction in all seasons, and mitigation in the area of multi-year ice in the central Arctic Ocean. These changes allow for increases in maritime access throughout the Arctic Ocean and for potential longer seasons of navigation and possibly transarctic voyage in the summer. These changes also allow more exploration for oil, gas, and other minerals. The Arctic is now an archetype of the complex, multi-dimensional global problems of the twenty-first century. Military security, environmental security, and economic security interact. The potentially enormous economic stakes, sufficient to change the strategic balance among the states of the region, set off competitive pressures for national advantage. Korea, which is heavily dependent upon the sea lane in terms of transportation of its exports and imports, is very much interested in the Arctic sea routes. Korea believes that the Artic sea route, particularly the Northern Sea Route (NSR), could serve as a new useful sea lane, which will enable shorter times between East Asia and Europe, thus resulting in substantial cost saving for ship operators. In addition to shipping, Korea is interested in other Arctic-related maritime industries. Korea, as a leading shipbuilder in the global market, is interested in building ice breakers, drill ships, and other vessels which can contribute to safe operation in Arctic resource development and exploration. Korea, as one of the future stakeholders in Arctic maritime activities, should be ready to foster international cooperation in the region.

• 전자통신동향분석
• /
• 제27권2호
• /
• pp.51-58
• /
• 2012

1990년대 말부터 IMO(International Maritime Organization)의 SOLAS(Safety of Life at Sea) 조약에 따라 300톤 이상의 모든 선박에 GMDSS(Global Maritime Distress & Safety System)를 탑재함으로써 전 세계 어디에서나 선박의 조난 및 안전 통신을 위한 육 해상 통합시스템의 기틀이 마련되었다. 최근에는 GMDSS의 현대화와 e-Navigation 개발전략에 따라 해상통신 기술의 디지털화와 음성에서 데이터 통신으로의 큰 변화가 예상된다. 이에 GMDSS 중심의 해상통신 기술현황을 위성, MF(Medium Frequency), HF(High Frequency), VHF(Very High Frequency) 등 다양한 통신 기술에 따라 설명하고 e-Navigation 개발전략에 따라 해상통신 기술의 발전 방향을 살펴보도록 한다.