• International Journal of Fuzzy Logic and Intelligent Systems
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• 제6권4호
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• pp.314-320
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• 2006

Navigation in environments that are densely cluttered with obstacles is still a challenge for Autonomous Ground Vehicles (AGVs), especially when the configuration of obstacles is not known a priori. Reactive local navigation schemes that tightly couple the robot actions to the sensor information have proved to be effective in these environments, and because of the environmental uncertainties, STSF(Space and Time Sensor Fusion)-based fuzzy behavior systems have been proposed. Realization of autonomous behavior in mobile robots, using STSF control based on spatial data fusion, requires formulation of rules which are collectively responsible for necessary levels of intelligence. This collection of rules can be conveniently decomposed and efficiently implemented as a hierarchy of fuzzy-behaviors. This paper describes how this can be done using a behavior-based architecture. The approach is motivated by ethological models which suggest hierarchical organizations of behavior. Experimental results show that the proposed method can smoothly and effectively guide a robot through cluttered environments such as dense forests.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2012년도 추계학술대회
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• pp.311-312
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• 2012

부산광역시라는 대도심 속의 어촌마을로 자리하고 있는 기장지역은 예로부터 해양문화와 친밀하게 발전하여 왔다. 하지만 다른 한편 역사적인 연유로 위축 상실된 우리나라의 해양성은 필요 이상으로 비하되고 천대받아온 건 또한 해양에 관련한 전반적인 인식이다. 따라서, 과거 2003년 부터 추진되어온 이 지역의 이색적인 등대 개발을 통해 지역문화를 활성화 하고 해양문화를 창출시키는 수단으로서 등대의 관광자원화를 논하고자 한다.

• Journal of Mechanical Science and Technology
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• 제17권11호
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• pp.1693-1703
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• 2003

This paper presents a new local obstacle avoidance method for indoor mobile robots. The method uses a new directional approach called the Lane Method. The Lane Method is combined with a velocity space method i.e., the Curvature-Velocity Method to form the Lane-Curvature Method (LCM). The Lane Method divides the work area into lanes, and then chooses the best lane to follow to optimize travel along a desired goal heading. A local heading is then calculated for entering and following the best lane, and CVM uses this local heading to determine the optimal translational and rotational velocities, considering some physical limitations and environmental constraint. By combining both the directional and velocity space methods, LCM yields safe collision-free motion as well as smooth motion taking the physical limitations of the robot motion into account.

• 한국군사과학기술학회지
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• 제14권3호
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• pp.327-334
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• 2011

It is necessary that UGV(Unmanned Ground Vehicle) should generate a real-time travesability index map by analyzing raw terrain information to travel autonomously tough terrain which has various slope and roughness values. In this paper, we propose a local path planning method, $MA^*$(Modified $A^*$) algorithm, using DVGM (Directional Velocity Grid Map) for unmanned ground vehicle. We also present a path optimization algorithm and a path smoothing algorithm which regenerate a pre-planned local path by $MA^*$ algorithm into the reasonable local path considering the mobility of UGV. Field test is conducted with UGV in order to verify the performance of local path planning method using DVGM. The local path planned by $MA^*$ is compared with the result of $A^*$ to verify the safety and optimality of proposed algorithm.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 Asia Navigation Conference
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• pp.203-212
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• 2006

The purpose of this research is to suggest the activation plan of Busan port. In the past years, Busan port enjoyed the golden days because of the China's rapid economic growth. But China's continuous development of ports, the trend of increasing container ship size and increasing direct call to China are coming threats to Busan port. So Korea needs to revise the 'Northeast Logistics Hub' strategy because it is considered that Korea ports continuously will handle China's transshipment cargoes. But now China's transshipment cargo share has decreased by direct call to China ports. It means that China has a lot of its local cargoes, so many ship companies change liner service route to handle China cargoes except Bussan ports although Busan port is included in the main trunk route. In the future, Bussan port will not be able to compete again about throughput with China ports if Busan port's transshipment cargo share decreases. So we must find out and develop Busan port's strength which is the competitive edge. By good luck, Busan port has a few opportunities such as the developed feeder network service and geographical advantages. Busan port has many feeder network service like spider's web in any northeast countries so we can suggest that if Japanese shippers use Busan port to distribute their cargoes to Japanese local areas, its transport costs are cheaper than when they use Japan's main ports. In this paper analyzed side of cost when they use Bussan port like hub to distribute their cargo to their local areas. Because most companies tried to reduce the total cost about logistics. Finally, this paper suggests when northeast shippers(China, Japan) use Bussan port which is more economical than their local main ports.

• 한국항해항만학회지
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• 제36권8호
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• pp.691-698
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• 2012

국내 국제물류주선업체가 직면한 수익성 악화, 고용 불안 및 포화 상태에 있는 국내 물류시장에 대하여 알아보고 글로벌 시장 진출을 위한 블루오션 전략으로 유엔 조달시장 현황, 참가 방법, 성공적인 진출 방안, 글로벌 진출 활성화 지원책들을 연구한다. 현재 유엔 조달물류시장에 대한 국내의 연구 자료가 없지만, 저자가 조달 물류서비스 입찰에 참여한 경험으로 유엔 조달 물류시장 진출 방안은 유엔 벤더로 등록한 물류기업에 대한 정부의 해외진출사업 지원 확대, KOTRA "P300 프로젝트"에 선정된 물류 선도 기업들에 제공되는 유엔 조달 지역 입찰 정보를 활용한 경쟁력 제고, 유엔 조달 물류 특성상 오지 지역 운송에 대한 글로벌 네트워크 구축, 정부의 기존 해외인턴제도와 연계한 전문 인력양성 교육 프로그램 개발이 필요하다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.231-231
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• 2017

• 한국통신학회논문지
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• 제38A권10호
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• pp.845-849
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• 2013

본 논문에서는 Galileo 시스템에 사용할 이진 옵셋 반송파 (binary offset carrier: BOC) 신호의 자기상관함수가 갖는 주변 첨두를 제거하기 위해 국소신호를 설계한다. 구체적으로는 BOC 신호를 분석하여 기존 기법의 국소신호가 사인 혹은 코사인 위상의 BOC 신호에만 적용되는 것을 밝히고, 사인과 코사인 위상 BOC 신호에 모두 적용 가능한 국소신호를 설계한다. 이후 설계한 국소신호와 수신 BOC 신호를 상관하고 상관한 부상관함수를 조합함으로써 주변 첨두가 제거된 상관함수를 생성한다. 모의실험을 통해 설계한 국소신호를 이용하여 생성한 상관함수는 주변 첨두가 모두 제거될 뿐만 아니라 설계한 국소신호는 사인과 코사인 위상 BOC 신호에 모두 적용되는 것을 확인한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1606-1611
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• 2005

The goal of this paper is to develop a self localization of mobile robot using UHF RFID landmark. We present landmark, a location sensing archetype system that uses UHF Radio Frequency Identification (UHF RFID) technology for locating objects inside buildings. The major advantage of landmark is that it improves the overall accuracy of locating objects by utilizing the concept of reference tags. Based on experimental analysis, we demonstrate that passive UHF RFID is a viable and cost-effective candidate for indoor location sensing. We conduct a series of experiments to evaluate performance of the positioning of the landmark System. In the standard setup, we place RF Reader which has two antennas and 25 tags in our lab. This research uses the assumption-based coordinates (ABC) algorithm[3] for determining the localization of robot. Also, we show how Radio Frequency Identification (UHF RFID) can be used in robot-assisted indoor navigation for the visually impaired. The experiments illustrate that passive UHF RFID tags can act as reliable landmark that trigger local navigation behaviors to achieve global navigation objectives.

• Journal of Astronomy and Space Sciences
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• 제35권3호
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• pp.119-131
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• 2018

In spite of a short history of only 30 years in space development, Korea has achieved outstanding space development capabilities, and became the $11^{th}$ member of the "Space Club" in 2013 by launching its own satellites with its own launch vehicle from a local space center. With the successful development and operation of more than 10 earth-orbiting satellites since 1999, Korea is now rapidly expanding its own aspirations to outer space exploration. Unlike earth-orbiting missions, planetary missions are more demanding of well-rounded technological capabilities, specifically trajectory design, analysis, and navigation. Because of the importance of relevant technologies, the Korean astronautical society devoted significant efforts to secure these basic technologies from the early 2000s. This paper revisits the numerous efforts conducted to date, specifically regarding flight dynamics and navigation technology, to prepare for future upcoming planetary missions in Korea. However, sustained efforts are still required to realize such challenging planetary missions, and efforts to date will significantly advance the relevant Korean technological capabilities.