• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.2
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• pp.186-192
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• 2014

In this paper, we analysed vessel traffic volume and patterns of traffic flow for ships using areas where included wind farm site and adjacent waters of Daejeong Offshore Wind Farm, and estimated traffic volume by classified navigational routes according to suggestion of rational routeing measures on the basis of classified patterns after installation of offshore wind facilities. Also, we assessed vessel traffic safety for each designed routeing measures on the basis of estimated traffic volume and proposed requisite countermeasures for the safe navigation of ships. With a result of analysing patterns of traffic flow, the current traffic flow was classified by 8 patterns and the annual traffic volume was predicted to 8,975 ships. On the basis of these, expected the vessel traffic volume according to designed four routeing mesaures after installation of wind farm. As result of assessing vessel traffic safety by using powered-vessel collision model of SSPA on the basis of the estimated traffic volume, the value of collision probability was less than safe criteria $10^{-4}$. Thereby we made sure usability of the designed routeing measures for the safe navigation of ships.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.2
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• pp.36-46
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• 2020

This study is designed to help customers use more comfortable airports by predicting congestion and congestion times by identifying the traffic routes of passengers in the airport building by day of the week and time by using Wi-Fi sensor collectors, one of the IoT technologies. Analysis of passenger traffic analysis data showed that the most congested time zones were from noon. to 2p.m. for all facilities, which could be used to improve major facilities. Regression analysis of factors affecting congestion found that self-check-in reduces congestion and check-in counters increases congestion. These findings will provide important implications for operations, including congestion management at airports.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.9 no.1
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• pp.31-44
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• 2001

This paper addresses legislation status of air route design standard of Korea. Korea Ministry of Construction and Transportation's Order Number 300 (March 28, 2001) prescribes that firstly, the design of air routes in Korea should be in accord with International Civil Aviation Organization(ICAO)'s recommendations published in Annex 11: Air Traffic Service and Procedures for Air Navigation Services: Aircraft Operations (ICAO Doc 8168-OPS, 1986), and secondly, United States Federal Aviation Administration(FAA)'s Terminal Instrument Procedures (FAA, 1976). An investigation on the current air route specifications of Korea reveals that they are in accord with neither ICAO's recommendations nor FAA's standards in that the width of Korea's air routes are narrower that the international recommendations and standards. As a member state of ICAO, it is imperative for Korea to follow the international standards. In that purposes, Korea should legislate and regulate the detail standard for air route design. For the legislation, FAA regulations are to be followed because FAA rules contains more detail specifications while ICAO recommendations includes allows a range of policy decisions, which may result in a confusion in practice.

• Journal of the Korean Society for Railway
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• v.10 no.2 s.39
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• pp.179-185
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• 2007

In large station with high density traffic, trains can be hardly controlled by CTC but by station dispatcher because CTC has difficulties in monitoring all states of affairs happening within each station such as departures, arrivals of many trains from different lines and shunting of trains to move between yards and platforms, etc. Therefore the station's dispatcher has to make quick decision about how to reschedule the times and routes for all the trains scheduled within a specific time window. And such decision becomes harder when an unexpected delay occurs because a delay occurring in a train propagates other trains as time goes on. Generally, it is called the conflict detection and resolution to adjust beforehand the distorted schedule due to a delay to original schedule. Our research is different from the state of the arts in that ours determines simultaneously the routes and the times of arrival and departure of trains, although others do only the arrival and departure time of the trains without considering the alternative routes and shunting of the station. This study suggests a mathematical approach for how to detect in advance and resolve efficiently the conflicts occurring within a station and it will be shown how to reduce delay using our approach by means of analysing the schedule of ChyungRyangRi station.

• Journal of Korean Society of Transportation
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• v.27 no.1
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• pp.63-71
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• 2009

The purpose of this paper is to identify unreliable routes in the view of users. After headway error ratio per route and travel time error ratio per route were calculated by using BMS data, reliability which incorporated two indicators each route was calculated through data envelopment analysis. Reliability among routes and among traffic zones was compared through the results, the needs to improve severely unreliable routes and to show passengers adjusted bus schedule information considering current reliability were suggested. As a future study, reliability evaluation framework of each route needs to be developed considering operation environment by analyzing bus card data (passengers and operation speed etc.) and pooly unreliable route should be managed strictly and reformed.

• Journal of Korean Port Research
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• v.12 no.2
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• pp.233-242
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• 1998

The Inchon port has been heavily congested due to the tidal restriction in passing the lock and the shortage of berths or warehouses. The current congestion is predicted to become worse by the induced traffics near the lock entrance after completion of North harbour expansion and of Kyung-In canal construction. It is also expected that the newly developed configuration of the Inchon port will result in increasing the rate of marine accidents around the lock entrance because of the over-utilization of the limited capacity of the junction from the North harbour and the Kyung-In canal. This study adopts a systematic approach in analysing the physical distribution system of the inner-lock area in order to figure out alternative routes which are designed to improve the port efficiency. Ship maneuvering simulation is also attempted to propose a new approaching route to the canal as an alternative path in order to avoid the traffic accidents caused by the extreme congestion. The result of the ship maneuvering simulation demonstrates that the alternative routes by way of Buk-Sudo, Janbong-Sudo, north of Si-Do and Sin-Do is recommended routes which can satisfy the safety requirements of approaching to the canal entrance.

• Proceedings of the KOR-KST Conference
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• 2000.02a
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• pp.25-47
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• 2000

In route guidance systems fastest-path routing has typically been adopted because of its simplicity. However, empirical studies on route choice behavior have shown that drivers use numerous criteria in choosing a route. The objective of this study is to develop computationally efficient algorithms for identifying a manageable subset of the nondominated (i.e. Pareto optimal) paths for real-time vehicle routing which reflect the drivers' preferences and route choice behaviors. We propose two pruning algorithms that reduce the search area based on a context-dependent linear utility function and thus reduce the computation time. The basic notion of the proposed approach is that ⅰ) enumerating all nondominated paths is computationally too expensive, ⅱ) obtaining a stable mathematical representation of the drivers' utility function is theoretically difficult and impractical, and ⅲ) obtaining optimal path given a nonlinear utility function is a NP-hard problem. Consequently, a heuristic two-stage strategy which identifies multiple routes and then select the near-optimal path may be effective and practical. As the first stage, we utilize the relaxation based pruning technique based on an entropy model to recognize and discard most of the nondominated paths that do not reflect the drivers' preference and/or the context-dependency of the preference. In addition, to make sure that paths identified are dissimilar in terms of links used, the number of shared links between routes is limited. We test the proposed algorithms in a large real-life traffic network and show that the algorithms reduce CPU time significantly compared with conventional multi-criteria shortest path algorithms while the attributes of the routes identified reflect drivers' preferences and generic route choice behaviors well.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.4
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• pp.126-132
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• 2023

During the COVID-19 pandemic, there have been many changes in the aviation industry as a whole. Passenger traffic has decreased, but on the contrary, the international transport demand for cargo planes has never been higher. Due to their geopolitical location when flying to major cities around the world, Korea's international pilots are bound to have relatively more jet lag-causing routes than their American or European-based pilots. Through this study, we tried to analyze the degree of fatigue and fatigue weighting factors according to operating conditions for domestic pilots. As a result of the study, the following conclusions were drawn. Despite the variety of models, routes, and fatigue between individuals, it was found that the 3 Pilot operation route was concentrated as a representative fatigue route. Most of the individual fatigue improvement request sections showed higher fatigue as the night flight section was longer among the 3Pilot routes for more than 12 hours, and 43 out of 90 participants (Korean Air pilots) focused on 3Pilot (two captains and one pilot) as fatigue-intensive operating conditions. Therefore, it proposes an improvement in the system of applying 12-hour unification standards according to Korea's geopolitical international operating conditions and time difference standards.

• Journal of Korean Society of Transportation
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• v.29 no.6
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• pp.129-136
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• 2011

Variable Message Signs have been used for providing information on the current traffic conditions. However, it is considered more important to achieve optimal traffic allocation among the alternative routes by strategic VMS information provision. Fuzzy control is very effective and efficient to deal with such systems that are too complex and uncertain to build mathematical models. In this paper, a fuzzy feedback controller for VMS is proposed, whose goal is to achieve the travel time equilibrium between the two alternative routes. The performance of the suggested controller is implemented and examined using MATLAB/Simulink. More robust controller applicable to a real highway network is suggested for the further research.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.582-585
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• 2018

As traffic volume increases and road networks become more complicated, identifying for accurate traffic flow and driving smooth traffic flow are a concern of many countries. There are various analytical techniques and studies which desire to study about effective traffic flow. However, the necessary activity is finding the traffic flow pattern through data visualization including location information. In this paper aim to study a real-world urban traffic trajectory and visualize a pattern of traffic flow with a simulation tool. Our experiment is installing the sensor module in 40 taxis and our dataset is generated along 24 hours and unscheduled routes. After pre-processing data, we improved an open source traffic visualize tools to suitable for our experiment. Then we simulate our vehicle trajectory data with a dots animation over a period of time, which allows clearly view a traffic flow simulation and a understand the direction of movement of the vehicle or route pattern. In addition we further propose some novel timelines to show spatial-temporal features to improve an urban environment due to the traffic flow.