• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.6
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• pp.1033-1041
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• 2017

Path travel time based on departure time (PTTDP) is key information in advanced traveler information systems (ATIS). Despite the necessity, forecasting PTTDP is still one of challenges which should be successfully conquered in the forecasting area of intelligent transportation systems (ITS). To address this problem effectively, a methodology to dynamically predict PTTDP between motorway interchanges is proposed in this paper. The method was developed based on the relationships between traffic demands at motorway tollgates and PTTDPs between TGs in the motorway network. Two different data were used as the input of the model: traffic demand data and path travel time data are collected by toll collection system (TCS) and dedicated short range communication (DSRC), respectively. The proposed model was developed based on k-nearest neighbor, one of data mining techniques, in order for the real applications of motorway information systems. In a feasible test with real-world data, the proposed method performed effectively by means of prediction reliability and computational running time to the level of real application of current ATIS.

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.23-31
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• 2019

In this study, we collected data through online travel notes from January to December 2018 and analyzed the seasonal travel characteristics of individual visiting Chinese by utilizing social network analysis. The analysis showed that Seoul is a hub for Chinese travel to Korea and the main destinations for individual visiting Chinese are concentrated in Seoul, Busan, Jeju Island, Gyeongju and Gangneung, with wide differences in seasons. The research results can be used as basic data for the development of tourism courses for individual Chinese tourists to Korea, provision of tourism services and optimization of tourism facility layout. Future research can consider continuing to use network travel notes to study the tourist destination and the mode of transportation between tourist nodes, which can provide reference for the development of tourist market and the planning and design of tourist traffic.

• Journal of Korean Society of Transportation
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• v.33 no.1
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• pp.50-60
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• 2015

Pedestrians not only walk along roads, but also pass through buildings or across open spaces. This study defines these unusual walk routes as social path. Social path is an informal pedestrian route that is not considered in a pedestrian network, even though it should be regarded as pedestrian route considering the fact that many people actually use this path. In response, current study related to travel behavior cannot evaluate properly due to lack of consideration for realistic travel behavior such as social path. In order to deal with this situation, this study analyzes the effect of social path at two complex centers in Seoul. Evaluation indices are service area analysis and urban network analysis which is one of the spatial network analysis. In particular, we subdivide the network into three steps by the level of network building and analyze each step. As a result, it is revealed that step three which includes social path shows the greatest improvement in pedestrian accessibility. In this regard, we confirm that social path should be considered when evaluating pedestrian accessibility in further studies. Furthermore, a lot of undervalued facilities will be re-appraised in the field of travel behavior.

• Agricultural and Biosystems Engineering
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• v.2 no.2
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• pp.50-58
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• 2001

Chemical application is very hazardous in confined spaces under the canopy ceiling in Korean vineyard. For a small orchard sprayer adaptable to such a working condition, a low-cost autonomous steering control system was developed using two ultrasonic sensors, two electrically-operated cylinders and 80196kc microprocessor. A distance ranging system timed the round-trip for each ultrasonic wave to travel against parallel targets, placed every 1.5m spacing along both sides of a desired path. A steering control algorithm of the autonomous operation began with ranging left and right targets and the heading was decided using difference between the distances. Electrically-operated cylinders actuated steering clutches to guide the sprayer. Evaluation tests showed that the orchard sprayer could travel within RMS value of 5cm along the desired path. Ground speed did not affect the performance of the autonomous guidance system at the speed ranges of 0.29~0.52m/sec.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.5
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• pp.592-598
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• 2008

This paper presents collision prediction and avoidance method for AGVS (Automatic Guide Vehicle System). Also, we propose the PO(Right of Path Occupying) with decentralized delay time for collision avoidance. Classified essential element of AGV's working environment is modeled in this paper. Using this model, we propose a new shortest path algorithm using A* search algorithm and obtain the information on AGVs travel time, coordinates and rotation vector. Finally, we use the AGVs information data as input for simulation program. The simulation practice is used in order to evaluate a collision prediction and avoidance, and it has been presented to demonstrate the applicability of the minimize delay time.

• The Korean Journal of Applied Statistics
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• v.20 no.3
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• pp.459-473
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• 2007

In this paper, we suggest a spatial regression model to predict AADT. Although Euclidian distances between one monitoring site and its neighboring sites were usually used in the many analysis, we consider the shortest travel path between monitoring sites to predict AADT for unmonitoring site using spatial regression model. We used universal Kriging method for prediction and found that the overall predictive capability of the spatial regression model based on shortest travel path is better than that of the model based on multiple regression by cross validation.

• Journal of Industrial Technology
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• v.21 no.A
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• pp.241-249
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• 2001

The objective of this paper is to develop the optimal path algorithm for dynamic route guidance system in advanced traveler information system (ATIS). The travel time is forecasted in each path between network nodes. Floyd-Warshall algorithm is used to find the optimal route based on this forecasted travel time in dynamic traffic network. This algorithm is modified to apply the real traffic network that has left-turn restriction, U-turn, and P-turn. A big value is assigned to one of arcs in turn restriction and a virtual node is used to consider U-turn and P-turn for Floyd-Warshall algorithm.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.479-483
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• 2015

In case of the big city, choosing the adequate root of which we can reach the destination can affect the driver's condition and driving time. so it is quite important to find the optimal routes for arriving the destination as considering the factors, such as driving conditions or travel time and so on. In this paper, we develop route choice model with considering driving conditions and travel time, and it can search the optimal path which make drivers reduce their fatigues using genetic algorithm.

• Journal of the Korea Convergence Society
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• v.10 no.4
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• pp.39-43
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• 2019

The gantry of surface mount equipment (SMD) is responsible for transferring parts from the feeder to the PCB. At this time, the moving time of the gantry affects the yield. Therefore, in this paper, we propose the fastest path from the suction to the mounting to reduce the gantry travel time. This path is a case where the velocity in front of the camera is 2m/sec due to the nature of the gantry. Therefore, the trajectory graph of this case was created through simulation and the travel time was calculated. As a result, we can see that the moving time of the moving-motion method proposed in this paper is 20% shorter than the current stop-motion method.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.3 s.8
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• pp.9-22
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• 2005

Route travel cost in transportation networks consists of actual route travel cost and route perception cost. Since the route perception cost is differently perceived according to each origin and each destination, route search has limitation to reflect the note perception cost due to route enumeration problem. Thus, currently employed advanced traveller information systems (ATIS) have considered only actual route travel cost for providing route information. This study proposes an optimal and a K-route searching algorithm which are able to reflect the route perception cost but encompass route enumeration problem. For this purpose, this research defines the minimum nit of route as a link by adopting the link label technique in route searching, therefore the comparison of two adjacent links which can be finally expanded the comparison of two routes. In order to reflect the characteristics of route perception in real situation, an optimal shortest cost path algorithm that both the forward search from the origin and the backward search from the destination can be simultaneously processed is proposed. The proposed algorithm is applied for finding K number of shortest routes with an entire-path-deletion-type of K shortest route algorithm.