• 한국항해학회지
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• 제25권1호
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• pp.77-91
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• 2001

본 연구의 목적은 통일신라시대의 해상왕 장보고의 해상항로를 추정하기 위하여 우리나라 고대부터 통일신라시대까지의 해상활동, 그리고 당시의 중국과 일본의 해상활동을 우리나라와 중국의 고대 문헌, 그리고 9세기 초 아랍의 지리학자인 Ibn Khurdahbih와 Al-Biruni, Al-Idrisi의 문헌 등을 고찰하고, 이를 근거로 하여 통일신라시대의 해상왕 장보고의 해상항로를 추정하는데 있다. 연구의 결과 해상왕 장보고는 우리나라 고대부터 축적된 조선술과 항해술을 이용하여 노철산 항로, 황해 횡단항로, 동지나 횡단항로, 황해와 남지나해를 연결하는 해상항로, 황해$\longrightarrow$남해$\longrightarrow$대마도를 연결하는 대마도 항로, 신라$\longrightarrow$울릉도 가느이 동해 항로, 발해와 일본을 연결하는 동해 직항로, 그리고 중국의 주산군도를 기점으로 하여 북쪽을 향하는 해상항로와 남쪽으로 가는 해상항로를 이용하여 중국, 일본 등과 교류를 하였고, 당나라의 연안을 따라 광주$\longrightarrow$남지나해$\longrightarrow$베트남$\longrightarrow$싱가포르 해협$\longrightarrow$말라가 해협$\longrightarrow$스리랑카$\longrightarrow$인도$\longrightarrow$인도양$\longrightarrow$페르시아만의 아랍국가$\longrightarrow$아프리카 동쪽 해안을 연결하는 서방 해상항로, 그리고 당나라의 광주$\longrightarrow$유구$\longrightarrow$통일신라$\longrightarrow$통일신라를 연결하는 해상항로를 이용하여 중국, 일본뿐만 아니라 베트남, 인도네시아, 말레이시아, 스리랑카, 인도, 페르시아만의 아랍-이슬람 제국과도 해상항로를 개설하여 활발한 해상활동을 하였던 것으로 추정이 된다.

• 한국항만경제학회지
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• 제38권1호
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• pp.113-127
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• 2022

본 연구는 DEA Window 모형을 활용하여 국내 내항여객운송항로 90개 항로를 의사결정단위(DMU: Decision Making Unit)하여 효율성을 분석하는 것을 목적으로 하였다. 2015~2019년 데이터를 원도우 3기로 구분하고, 선박의 운항횟수, 선박총톤수 및 운항거리를 투입변수로, 일반인 및 도서민 운송실적을 산출변수로 하여 효율성을 분석하였다. 분석결과 상대적 효율성이 낮은 항로에 대해서는 개선사항을 도출하여 제시하였다. 특히 수익항로로 민간사업자가 선박을 운항하고 있는 일반항로와 비수익항로로 국가가 지원하고 있는 보조항로에 대해 효율성 평가를 하였다. 아울러 CCR모형의 기술효율성(technical efficiency: TE)과 BCC모형의 순수기술 효율성(pure technical efficiency: PTE) 값을 활용하여 규모효율성(scale efficiency: SE)을 도출하였다. 항로의 비효율성은 규모효율성(SE)보다 순수기술 효율성(PTE)에 의한 것임을 알 수 있었다. 본 연구의 분석결과에 나타난 각 항로에 대한 개선사항을 고려하여 내항여객운송항로 정책 수립시 고려할 필요가 있을 것이다.

• Journal of Electrical Engineering and Technology
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• 제10권4호
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• pp.1836-1842
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• 2015

On road networks, the clustering of moving objects is important for traffic monitoring and routes recommendation. The existing schemes find out density route by considering the number of vehicles in a road segment. Since they don’t consider the features of each road segment such as width, length, and directions in a road network, the results are not correct in some real road networks. To overcome such problems, we propose a clustering method for congested routes discovering from the trajectories of moving objects on road networks. The proposed scheme can be divided into three steps. First, it divides each road network into segments with different width, length, and directions. Second, the congested road segments are detected through analyzing the trajectories of moving objects on the road network. The saturation degree of each road segment and the average moving speed of vehicles in a road segment are computed to detect the congested road segments. Finally, we compute the final congested routes by using a clustering scheme. The experimental results showed that the proposed scheme can efficiently discover the congested routes in different directions of the roads.

• ETRI Journal
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• 제40권5호
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• pp.613-623
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• 2018

The instability of operational channels on cognitive radio networks (CRNs), which is due to the stochastic behavior of primary users (PUs), has increased the complexity of the design of the optimal routing criterion (ORC) in CRNs. The exploitation of available opportunities in CRNs, such as the channel diversity, as well as alternative routes provided by the intermediate nodes belonging to routes (internal backup routes) in the route-cost (or weight) determination, complicate the ORC design. In this paper, to cover the channel diversity, the CRN is modeled as a multigraph in which the weight of each edge is determined according to the behavior of PU senders and the protection of PU receivers. Then, an ORC for CRNs, which is referred to as the stability probability of communication between the source node and the destination node (SPC_SD), is proposed. SPC_SD, which is based on the obtained model, internal backup routes, and probability theory, calculates the precise probability of communication stability between the source and destination. The performance evaluation is conducted using simulations, and the results show that the end-to-end performance improved significantly.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제26권1호
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• pp.7-15
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• 2020

Purpose: Emergency room(ER) is the first place to enter a hospital where patients who might have been infected with contagious disease. Therefore, ER should be designed with infection control in mind. Researchers examined hospital ER layouts to identify layout design that support infection control. Methods: This study analyzed the hospital ER layout of Korean and other hospitals abroad. Researchers focused on route of incoming patients who potentially have infectious disease. Crossing of this route with other routes such as for imaging and testing should be avoided for infection control. Results: There were certain hospital ERs with better control of infection related incidents. ER floor plan layout is analyzed about allocation of key functions with movement routes for each role such as patients and medical staff in mind. To identify layout strategies for ER functions researchers simplified the routes in ER into diagrams. Layout options show that bypassing infection suspected routes over other routes is possible. Implications: Hospitals can control infection easier when they adopt strategic ER layout identified in this study.

• 기술사
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• 제41권2호
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• pp.51-58
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• 2008

In this paper is described "the water resources policy, a new paradigm of water resources control. the characteristic of rainfall in Korea and the compatibility of a new water routes opening in natural river". Also the construction of the Korean grand waterway in the view of disaster prevention, flood control, irrigation and environment-friendly transportation is needed eventually. And I detail a routes of Korean grand waterway, using of a flood gate, supply of irrigation water. cruse duration, activating under developed region and economic efficiency.

• 대한산업공학회지
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• 제16권2호
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• pp.71-79
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• 1990

In this paper, the Double Shortest Arborescence & Merging method is presented as an efficient heuristic algorithm for the Public Vehicle Routing Problem which is to find the minimum total cost routes of M or less vehicles to traverse the required arcs(demand streets) at least once and return to their starting depot on a directed network. Double Shortest Arborescence which consists of forward shortest aborescence and backward one informs M or less shortest routes to traverse all required arcs. The number of these routes is reduced to M or less by merging routes. The computational experiment based on randomly generated networks reports that this algorithm is efficient.

• 대한산업공학회지
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• 제28권1호
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• pp.25-35
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• 2002

This paper presents a heuristic algorithm that a mobile robot avoids obstacles using optical flow. Using optical flow, the mobile robot can easily avoid static obstacles without a prior position information as well as moving obstacles with unknown trajectories. The mobile robot in this paper is able to recognize the locations or routes of obstacles, which can be detected by obtaining 2-dimensional optical flow information from a CCD camera. It predicts the possibilities of crash with obstacles based on the comparison between planned routes and the obstacle routes. Then it modifies its driving route if necessary. Driving acceleration and angular velocity of mobile robot are applied as controlling variables of avoidance. The corresponding simulation test is performed to verify the effectiveness of these factors. The results of simulation show that the mobile robot can reach the goal with avoiding obstacles which have variable routes and speed.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(A)
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• pp.278-281
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• 2011

Mobile devices equipped with various sensors have the potential of providing context-aware services. Location is one of the most common forms of context, which can be applied to diverse applications. In this paper, we present methods for learning and predicting users' routes between significant locations, e.g., home and workplaces, based on personal GPS data. A user's significant locations and routes between them are learned by a set of rules as well as clustering. When the user is moving, our methods can predict which of the learned routes is being taken now. After the route prediction, the user's next location can also be inferred. Our methods have been applied to the real GPS datasets from four subjects. For the next location prediction task, the achieved accuracy was 84.8%.

• 한국경영과학회지
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• 제6권1호
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• pp.5-13
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• 1981

This paper considers a facility moving along a route of straight line to serve several facilities in xy plane. A route is obtained which minimizes the objective function expressed in terms of average rectilinear distance between the service facility and facilities to he served. The forms of the objective functions can be classified into several cases according to the initial and end points of the routes. In some cases, as in the problem of optimal location of new facility, the cordinates of the optimal routes are median of the cordinates of facilities to be served. In others, the optimal routes are obtained after examining the values of objective functions on the boundaries of slopes and intercepts. An overall optimal route is obtained by comparing these routes. The entire procedure has been programmed in BASIC language, and several case examples are given.