• Journal of Korean Society of Transportation
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• v.31 no.6
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• pp.22-33
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• 2013

Currently average daily traffic using Hi-pass has increased over 3 times that of 2008 and more than half of highway traffic now uses High-pass. At this juncture, reassessment on the overall operation of Hi-pass is required to improve the safety aspect of toll booths and the flow of traffic. Although existing Hi-pass operation manual presents the methods of alignment, they do not reflect actual forms of vehicles and do not properly take the safety of toll booth and flow of the traffic into consideration. In order to compensate these problems, this study classifies highway tollbooths into two categories of mainline type and interchange type, and establishes the standard of lane alignment by traffic conflict analysis based on the types divided according to geometric structure or environment around the tollbooths. In addition, traffic flows around the tollbooths were reflected with the stage to arrange Hi-pass lanes according to the volume of traffic on the lanes for Hi-pass.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.11
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• pp.1041-1049
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• 2012

The transactional memory was proposed to solve the problems of the conventional lock-based synchronization methods in the shared memory multiprocessor system. Various implementation methods for putting the high performance transactional memory to practical use have been continuously studied. However, these studies focus only on the commercialization and performance enhancement of the transactional memory. Besides, there have been few studies to analyze the system overhead of the transactional memory according to the conflict management policy. Thus this paper classifies hardware transactional memory, which is one kind of transactional memories, into four types according to the conflict management policy, and then compares and analyzes their performance and system bus traffic through their modeling and simulation. In addition, the most effective conflict management policy for the hardware transactional memory is presented through these comparison and analysis.

• Journal of information and communication convergence engineering
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• v.9 no.4
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• pp.405-410
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• 2011

In this paper, a conflict-avoided resource reservation scheme for UWB (Ultra Wide Band) WPAN (Wireless Personal Area Network) with D-MAC (Distributed Medium Access Control) is proposed. Since distributed characteristic of the WiMedia D-MAC supporting DRP (Distributed Reservation Protocol) scheme may cause lots of conflicts, overall performances of the WiMedia D-MAC can be deteriorated. In addition, once a DRP conflict occurs, only one of the DRP reservations involved in that DRP conflict maintains the reserved MASs, while the other DRP reservation must be terminated and DRP negotiations for them have to be re-started. Such DRP termination and renegotiation time delays due to the DRP conflicts can be a critical problem to the mobile devices transceiving real-time QoS traffic streams. Therefore, we propose a mechanism to avoid DRP conflicts by providing a kind of path diversity using relay transmission scheme and demonstrate its performance improvements via simulation results.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2736-2739
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• 2002

This paper is a study on the railway traffic conflict resolution(RTCR) using genetic algorithm(GA). Using GA, many complicated problems can be expressed in the easy way, and good solutions can be found in a reasonably short time. Due to the above merits, we focus to GA first of all. We express the sample RTCR problem and algorithm of Korean railroad using GA. From the Mark Ho's[2,3] results, we introduce a chromosome scheme in addition.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.190-203
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• 2003

열차경합의 사전검지 및 해소 시스템(Railway Conflict Detection and Resolution System, RDCRS)은 열차운행관리 시스템(Railway Traffic Management System, RTMS)의 최상위 의사결정지원 모듈이다. 본 논문에서는 한국철도에서 RCDRS의 필요성과 국외 적용현황 및 기존 연구현황을 분석한다. 또 RCDRS를 한국철도에 적용하기 위한 전반적인 방안을 한국철도 주요 노선별 열차운영 여건을 고려하여 제시한다. 또, 철도청에서 실시하는 '사령실 통합 신호설비 시설' 사업에 관한 RCDRS의 1단계 적용방안을 제시한다.

• 한국ITS학회:학술대회논문집
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• 2010.05a
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• pp.163-167
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• 2010

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.48-53
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• 2006

Noise mapping is performed in the city of Cheongju which has 626,614 inhabitants on a $153.41km^2$ area. This city has 71,387 buildings and 969,274m roads. Many database sets like information of roads, topography and buildings are required for making the noise map of large area. These database sets are provided by the various departments of the regional administration in Cheongju city. Using the given database sets, 3-dimensional model of topography and buildings are made to consider the multi-reflections and diffractions. A predicted noise level is compared with measured noise level of the road traffic noise. As the tool of management and decision of urban noise policy, noise map is combined into the map of land use to make the conflict noise map. This conflict noise map is useful to assess the present urban noise and to make the better life in complicated urban life.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.8
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• pp.739-747
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• 2015

With rapid growth in the technologies and demand of Remotely Piloted Aircraft Systems (RPASs), integration of such systems into the existing airspace system is becoming an issue in many countries. RPAS have different flight performances, communication characteristics, separation assurance mechanisms, and human machine interfaces from manned aircraft. To establish rules and regulations for RPAS integration, it is important to understand the impacts of RPASs on the airspace system. A simulation system that integrates manned aircraft, air traffic control, and RPASs is developed in Inha University to investigate these impacts through Human-in-The-Loop (HiTL) simulations. Three conflict resolution scenarios between a manned aircraft and a Remotely Piloted Aircraft (RPA) were constructed and tested. Human factors such as the response times of pilots and controllers were measured and analyzed as well as the risk of each maneuver.

• Journal of the Ergonomics Society of Korea
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• v.18 no.1
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• pp.133-147
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• 1999

Traffic signs without a cognitive consideration in their design may cause information-processing problem that could result in a mental confusion among drivers often lead to a serious traffic accident. Therefore, in this study, several traffic signs currently used in Seoul Metropolitan area have been sampled and analyzed to identify design problems that usually caused by neglecting drivers cognitive ability. To classify the practical design problems, five major information-processing problems have been suggested: indistinguishable information, information conflict, missing information, sign-load mismatch, and information overload. In order to solve these cognitive problems, new traffic signs have been suggested in this study. An experiment was also performed to validate the new traffic sign. Twenty-four healthy subjects participated in the experiment. They were asked to answer the Question after observing the traffic signs continuously displayed on computer screen. The result indicated that subjects improved the accuracy in understanding the signs by 1.4 times when they used the suggested traffic sign compared to the old one. Based upon the results, a cognitive guideline was suggested for correct and speedy reading of traffic signs by improving information processing and reducing of human error. In conclusion, the traffic sign may well be applied to design an intelligent traffic sign system to increase the safety and comfort of drivers, especially in complex load condition.

• Journal of Korean Society of Transportation
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• v.36 no.1
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• pp.38-50
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• 2018

Emerging automated driving environments will lead to a mixed traffic flow depending on the interaction between automated vehicles (AVs) and manually driven vehicles (MVs) because the market penetration rate (MPR) of AVs will gradually increase over time. Understanding the characteristics of mixed traffic conditions, and developing a method to control both AV and MV maneuverings smoothly is a backbone of the traffic management in the era of automated driving. To facilitate smooth vehicle interactions, the maneuvering of AVs should be properly determined by various traffic and road conditions, which motivates this study. This study investigated whether the aggressiveness of AV maneuvering, defined as automated driving aggressiveness (ADA), affect the performance of mixed traffic flow. VISSIM microscopic simulation experiments were conducted to derive proper ADAs for satisfying both the traffic safety and the operational efficiency. Traffic conflict rates and average travel speeds were used as indicators for the performance of safety and operations. While conducting simulations, level of service(LOS) and market penetration rate(MPR) of AVs were also taken into considerations. Results implies that an effective guideline to manage the ADA under various traffic and road conditions needs to be developed from the perspective of traffic operations to optimize traffic performances.