• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.7
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• pp.1509-1513
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• 2003

The autopilot system of vessel is proposed to take service safety and security, to elevate service efficiency, to decrease labor and to improve working environment. Ultimate purpose of the proposed system is to minimize the number of crew by guaranteeing economical efficiency of shipping service. Recently, the research is being achieved to compensate various nonlinear parameters of vessel and apply it to course keeping control, track keeping control, roll-rudder stabilization, dynamic ship positioning and automatic mooring control etc. using optimizing control technique. Relation between rudder angle controlled by steering machine of vessel and ship-heading angle, and load condition of ship is nonlinear, which affects various parameters of shipping service. The speed and direction of waves, velocity and quantity of wind, which also cause the non-linearity of it. Therefore the autopilot system of ship requires the robust control algorithm can overcome various non-linearity. On this paper, we design the autopilot system of ship, which overcomes nonlinear Parameters and disturbance of it using Fuzzy Algorithm, evaluate the proposed algorithm and its excellence through simulation.

• Journal of Auto-vehicle Safety Association
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• v.9 no.1
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• pp.6-12
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• 2017

Regulation for the testing and operation of automated vehicles on public roadways has been recently developed all over the world. For example, the licensing standards and the evaluation technology for automated vehicles have been proposed in California, Nevada and EU. But specific safety evaluation scenarios for automated vehicles have not been proposed yet. This paper presents safety evaluation scenarios for extraordinary service permission of automated vehicles on highways. A total of seven scenarios are selected in consideration of safety priority and real traffic situation. Six scenarios are relevant with lane keeping and one scenario is relevant with lane change. All scenarios are developed based on existing ADAS evaluation scenarios and repeated simulation of automated vehicle algorithm. Safety evaluation factors as well as scenarios are developed. The safety factors are based on existing ADAS ISO requirements, ADAS safety factors and current traffic regulations. For the scenarios, a hunter vehicle is needed in addition to automated vehicle evaluated. The hunter vehicle performs multiple roles like preceding vehicle, cut-in vehicle and so on. The hunter vehicle is also automated vehicle equipped with high performance GPS, radar and Lidar. All the scenarios can be implemented by driving a lap on a KATRI ITS test track. These scenarios and safety evaluation factors are investigated via both a computer simulation and an experimental vehicle test on the test track. The experimental vehicle test was conducted with two automated vehicles, which are the evaluated vehicle and the hunter vehicle.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.1
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• pp.1-6
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• 2020

Fast service access involves keeping track of the location of mobile users, while they are moving around the mobile network for a satisfactory level of QoS (Quality of Service) in a cost-effective manner. The location databases are used to keep track of Mobile Terminals (MT) so that incoming calls can be directed to requested mobile terminals at all times. MT reporting cell system used in location management is to designate each cell in the network as a reporting cell or a non-reporting cell. Determination of an optimal number of reporting cells (or reporting cell configuration) for a given network is reporting cell planning (RCP) problem. This is a difficult combinatorial optimization problem which has an exponential complexity. We can see that a cell in a network is either a reporting cell or a non-reporting cell. Hence, for a given network with N cells, the number of possible solutions is 2^N. We propose a biogeography based optimization (BBO) for design of mobile station location management system in wireless communication network. The number and locations of reporting cells should be determined to balance the registration for location update and paging operations for search the mobile stations to minimize the cost of system. Experimental results show that our proposed BBO is a fairly effective and competitive approach with respect to solution quality for optimally designing location management system because BBO is suitable for combinatorial optimization and multi-functional problems.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1077-1083
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• 2011

Turnout is one of railroad track components. The turnout is used to change train routes to near other sections when keeping the train speed. There are many accidents in the section including the turnout. The number of accidents and errors is 363 for ten years in the section including the turnout and annual average is 36.3. To ensure safety of the turnout, it is necessary to install monitoring systems. By using the monitoring systems, it is able to accumulate related information, develop maintenance and take a step for accidents in advance. Hence, The number of accidents and errors is decreased in the section including the turnout. So, when new turnout is installed, it is needed to use monitoring systems. Therefore, combined turnout management system is needed in Korea. It is possible to perform efficient maintenance because real-time monitoring system by using sensors and data-base management system. In this paper, accidents in the section including domestic turnout are analyzed and foreign combined turnout management system is presented. Hence, articles for installing the combined turnout management system in Korea are proposed.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.1
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• pp.199-208
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• 2001

In this paper, an automatic route tracking algorithm using the position variables and the yaw angle of a ship is suggested, Since most autopilot systems paly only a role of course-keeping by integrating the gyrocompass output, they cannot cope with position errors between the desired route and real route of the ship resulted from a drifting and disturbances such as wave, wind and currents during navigation. In order for autopilot systems to track the desired route, a method which can reduce such position errors is required and some algorithms have been proposed[1,2]While such were turned out effective methods, they have a shortage that the rudder control actions for reducing the position errors are occurred very frequently. In order to improve this problem it is necessary to convert that error into the corresponding yaw angle and necessary to treat only yaw angle control problem. To do this a command generation algorithm which converts the rudder angle command reducing the current position error into they yaw angle command is suggested. To control the ship under disturbances and nonlinearities of the ship dynamics, the adaptive fuzzy controller is developed. Finally, through computer simulations for two ship models, the effectiveness of the suggested method and the possibility of the automatic route tracking are assured.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.1
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• pp.112-118
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• 2013

Formula race car is generally recognized as a vehicle which is optimally designed for on-road race track with the regulations of race host bodies. Especially, the uprights of suspension system decisively have effects on the performance of cornering and stability of race car's driving performance, which are very important factors in the design of race car. This paper is a study of optimal upright design of F1800 grade formula race car which are normally used in professional race circuit in Korea. To design optimally the front upright of F1800 formula race car, Taguchi's orthogonal array, which is known for more useful method than full factorial design experimental method in cost and time, is used with CAE method such as FEM analysis. And the result of this paper shows that Taguchi's orthogonal array employed for this optimal design is very useful for designing the front upright of race car by minimizing its weight as well as keeping its safety factor as enough as designer wants in the view of quality, cost and delivery at the early design step.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.460-464
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• 2003

The objects which continuously change their locations in the real world are called moving objects. The works on the existing spatial indices have been proposed the retrieval methods. However, keeping track of the terminal location of moving objects is more important than the efficiency of the query processing in the moving object database. Therefore, many pure spatial indices are not applicable to the moving objects database which should maintain the object's current location as precise as possible. This parer proposes a method for reducing the construction time of indexing moving objects. We analyze the characteristics of the method to re-index all the objects after each time period and the method to update immediately the locations on reporting their locations. We also newly propose a selective immediate update method using the properties of moving objects in order to minimize the number of database updates.

• Journal of Convergence Society for SMB
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• v.2 no.1
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• pp.41-50
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• 2012

In this research, we developed a scalable resource monitoring system for large scale scientific computing data centers. Usually, there are limitations and overheads for keeping track of every computing nodes because of the huge number of computing nodes. So, this research proposes a layered summarizing techniques during collection of all system resource information. The technique results in improved scalability by reducing the amount of information at higher layer. Our prototype system which is implemented with web service is applicable with the HTML5 mobile web technology on smart devices.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.4
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• pp.353-358
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• 2012

Human detection is a challenging task in many fields because it is difficult to detect humans due to their variable appearance and posture. Furthermore, it is also hard to track the detected human because of their dynamic and unpredictable behavior. The evaluation speed of method is also important as well as its accuracy. In this paper, we propose unified detection and tracking method for humans using Gaussian-PSO (Gaussian Particle Swarm Optimization) with the HOG (Histograms of Oriented Gradients) features to achieve a fast and accurate performance. Keeping the robustness of HOG features on human detection, we raise the process speed in detection and tracking so that it can be used for real-time applications. These advantages are given by a simple process which needs just one linear-SVM classifier with HOG features and Gaussian-PSO procedure for the both of detection and tracking.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.6
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• pp.1276-1282
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• 2003

The works on the existing spatial indices have been proposed the retrieval methods. However, keeping track of the terminal location of moving objects is more important than the efficiency of the query processing in the moving object database. Therefore, many pure spatial indices are not applicable to the moving objects database which should maintain the object's current location as precise as possible. This paper proposes a method for reducing the construction time of indexing moving objects. We analyze the characteristics of the method to re-index all the objects after each time period and the method to update immediately the locations on reporting their locations. We also newly propose a selective immediate update method using the properties of moving objects in order to minimize the number of database updates.