• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.1
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• pp.58-70
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• 2020

Detour behavior on the expressway means that the driver uses the local road by passing the part of the expressway which is stagnant at the time of the traffic demand such as holidays. Since the detour rate was estimated through the survey at toll gate in the past, there was a difficulty in estimating the actual detour rate due to the small sample of the survey. In this study, we use DSRC-based route travel data to conduct empirical studies on detour patterns such as the estimation of actual detour rate, the improvement of travel time using detour road, and the correlation between traffic conditions on the expressway and detour rate. On the day of Chuseok and the day before Chuseok, the analysis of Giheung-DongtanIC→OsanIC and Seopyeongtaek IC→Walgott JC showed that the use of detour roads increased gradually during the congestion of the main line and travel time reduced when using detour roads, However, when the traffic congestion of the main line is not severe, the travel time increases when using the detour roads. The correlation between the traffic condition of the expressway and the actual detour rate has a negative correlation, which is consistent with the congestion pattern of the main line. The results of this study can be used to overcome limitations of detour pattern research based on surveys in the past and to establish a detour strategy for expressway sections where traffic demand is concentrated.

• Kyungpook Mathematical Journal
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• v.61 no.1
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• pp.205-212
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• 2021

We show that the forbidden detour move, essentially introduced by Kanenobu and Nelson, is an unknotting operation for virtual knots. Then we define the forbidden detour number of a virtual knot to be the minimal number of forbidden detour moves necessary to transform a diagram of the virtual knot into the trivial knot diagram. Some upper and lower bounds on the forbidden detour number are given in terms of the minimal number of real crossings or the coefficients of the affine index polynomial of the virtual knot.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.3
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• pp.41-50
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• 2010

This paper presents an investigation result that is made to determine dominant influencing factors and their specific impacts on motorist detour makings for VMS placements on freeway. This was necessary to provide engineers with a tool for evaluating VMS cost-effectiveness and its feasibility. This research found that additional travel time delay is the most influential variable in determining motorist detour makings. Also, more than 70% freeway motorists recognize the adjacent national roads as their detour routes, and both AADT and the distance to the entering point of the detour path are found to be dominating factors. Motorist detour ratio model by VMS placement on freeway is developed based on the Stated Preference. In model validation, actual detour making behaviors observed by the Revealed Preference values verify the detour ratio on the Stated Preference. These research findings should be useful for cost-effective placements of VMS on freeway, and it is recommended that the results be tested by practicing engineers in the ITS sector.

• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.247-250
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• 2002

It is predicted that the existing backbone network has encountered its limit due to massive growth in data traffic. Perhaps new WDM methods utilizing optical fibers are desirable. Also to assure reliance of the network detour routes fur collision recovery must be considered. But due to the redundancy occurred by allocating bandwidths to the detour route, the efficiency of the link my decline. In this paper, we designed a detour route to minimize the redundancy.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.3
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• pp.655-659
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• 2016

In this paper, we propose new detection and detour methods against packet drop attacks for availability in the Internet of Things (IoT) based on the IEEE 802.15.4e and RPL protocol standards that employ IPv6. We consider the rank value of RPL and the consecutive packet drops to improve the detection metrics, and also take into account the use of both sibling and child nodes on a RPL routing path to construct the detour method. Our simulation results show that the proposed detection method is faster than the previous result, and the detour method improves the detour success rate.

• Journal of Communications and Networks
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• v.11 no.4
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• pp.327-336
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• 2009

Geographic routing has been considered as an attractive approach in wireless sensor networks, since it routes data packets by using location information rather than global topology information. In geographic routing schemes, packets are usually sent along the boundary of a hole by face routing to detour the hole. As result, all data flows which need to detour the hole are concentrated on the boundary of the hole. This hole detour scheme results in much more energy consumption for nodes at the hole boundary, and the energy exhaustion of hole boundary nodes enlarges the holes. This is referred to as a hole diffusion problem. The perimeter mode may also lead to data collisions on the hole boundary nodes if multiple data flows need to bypass a hole simultaneously. In this paper, we propose a hole modeling and detour scheme for geographic routing in wire-less sensor networks. Our hole modeling and detour scheme can efficiently prevent hole diffusion, avoid the local minimum problem faced by geographic routing protocols, and reduce data collisions on the hole boundary nodes. Simulation results show that the proposed scheme is superior to the other protocols in terms of control overhead, average delivery delay and energy consumption.

• International Journal of Highway Engineering
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• v.17 no.6
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• pp.97-104
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• 2015

PURPOSES : Expressways experience chronic and recurring congestion, especially during weekends and holidays, because of the increased demands for leisure-related travel. The alternatives to solve chronic and recurring congestion may be three-fold: (1) physical expansion of expressway capacities, (2) road pricing, and (3) temporal and spatial distribution of traffic demands. Among these, the third alternative may be the most cost-effective method for the Korea Expressway Corporation (KEC) that can be achieved by using the existing ITS infrastructure. METHODS : KEC initiated a pilot study in which the traffic on congested expressways was managed by providing traffic condition information (i.e., travel times) of neighboring national highways for taking detours via variable message signs (VMS). This study aimed to estimate the detour rate, and the two pilot studies on Seohaean and Yeongdong expressways yielded many benefits. RESULTS : It was revealed that the total length of congestion segments decreased by 7.8 km, and the average travel speed increased by 5.3 km/h. CONCLUSIONS : Based on these findings, it was concluded that the propagation of detour information via VMSs during congestion hours can help reduce congestion on expressways and increase the benefits of the entire network.

• Journal of Korean Society of Transportation
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• v.33 no.3
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• pp.304-314
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• 2015

Detour of metro (subway) in metropolitan area has been regarded as one of inherent elements that make entire metro system less competitive than passenger cars. However, factors affecting detour of metro line is not specified clearly when a new subway system is planned or an existing system is improved. Previous detour-related studies was reviewed for developing 'distance efficeincy evaluation model' for metro as well as its counterpart (i.e. road). Metro line 3 (orange line) of Seoul metropolitan area was applied as a case study. As a results, the most detoured OD segment is Daechi - Apgujeong and its detour factor is 1.93 which means that the distance of the metro is 1.93 times longer distance compared to the distance of the road. The metro line 3 has averagely 20% longer distance compared to road for the identical O/D pairs.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.3
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• pp.321-325
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• 2008

Void areas(holes) as an inevitable phenomenon exist in geographic routing of wireless sensor networks, because the unpredictable and harsh nature application environment or uneven energy consumption. Most of the existing schemes for the issue tend to construct a static detour path to bypass a hole. The static detour path may lead to uneven energy consumption of the nodes on the perimeter of the hole; thus it may enlarge the hole. At the same time, traffic would concentrate on the peripheral node of the hole; thus the nodes on the perimeter of the hole tend to be depleted quietly. In previous work, we have proposed a hole geometric model to reduce the energy consumption and packet collisions of the nodes on the hole boundary. This scheme, however, still has the static detour path problem. Therefore, we extend the previous work by constructing a dynamic detour path hole geometric model for wireless sensor networks in this paper. The location of hole detour anchors is dynamically shifted according to Gaussian function, just generating dynamic hole detour paths.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.167-176
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• 2011

This study's purpose is to analyse factors of determination about detouring for makinga standard model in regard of unfavorableness and uncertainty when unspecified individual recipients make a decision at the time of course detour. In order to achieve this, we surveyed SP investigation whether making a detour or not for drivers as a target who take a high way and National highway. Based on this result, we analysed detour determination factors of drivers, establishing a combination model of Decision Tree and Neural Network model. The result demonstrates the effected factors on drivers' detour determination are in ordering of the recognition of alternative routevs, reliable and frequency of using traffic information, frequency of transition routes and age. Moreover, from the outcome in comparison with an existing model and prediction through undistributed data, the rate of combination model 8.7% illustrates the most predictable way in contrast with logit model 12.8%, and Individual Model of Decision Tree 13.8% which are existed. This reveals that the analysis of drivers' detour determination factors is valid to apply. Hence, overall study considers as a practical foundation to make effective detour strategies for increasing the utility of route networking and dispersion in the volume of traffic from now on.