• Journal of Advanced Research in Ocean Engineering
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• v.2 no.1
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• pp.40-47
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• 2016

This paper describes the design and performance of a hovering AUV constructed at KMOU (Korea Maritime and Ocean University). Before the field test, we analyzed the dynamic performance of the AUV using a simulation program made by Matlab & Simulink. Also, a PID controller was designed to control the thrusters. Using 4 thrusters (2 vertical and 2 horizontal), the AUV could be controlled using dynamic motion with 4-DOF. A simulation and field test were conducted with way-point tracking, maintaining the desired depth. To perform way-point tracking, the AUV can be fine-tuned to the desired heading angle through the LOS (Line Of Sight) method. This paper shows the results of simulation and field tests.

• Journal of the Korean Society for Marine Environment & Energy
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• v.2 no.1
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• pp.90-101
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• 1999

This paper is concerned with the design of automatic ship maneuvering system including automatic path tracking controller and automatic berthing controller. The optimal control technique is employed to design the automatic path tracking controller, which is based on the linearized equations of ship motion. The numerical example shows that the automatic path tracking controller is capable of tracking the line between way points which are determined by pilot a priori. The decentralized control technique is employed to design the automatic berthing controller. In addition to the automatic path tracking controller, the fuzzy logic controller is used to control the forward speed. The numerical example shows that the automatic berthing controller can be successfully implemented.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.316-321
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• 2007

This paper is proposed a novel method to approximate the maximum power for a photovoltaic inverter system and tracking method. It is designed for power systems application and utilities. The proposed Maximum Power Point Tracking(MPPT) control has the advantage to provide a new simple way to approximate the optimal or rated voltage, the optimal or rated current and maximum power rating produced by a solar panel and the photovoltaic inverter. And this straightforward method will be named linear reoriented coordinates method(LRCM) with the advantage that Pmax and $V_{op}$ can be approximated using the satre variable as the dynamic model without using complicate approximations or Taylor series. Furthermore tracking method is improved over 50% photovoltaic efficiency. This paper is proposed MPPT using LRMC and tracking method using weather condition of domestic moderate program technique. This paper is proposed the experimental results to verify the effectiveness of the new methods.

• Journal of Korea Multimedia Society
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• v.24 no.6
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• pp.796-804
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• 2021

In computer vision, visual tracking method addresses the problem of localizing an specific object in video sequence according to the bounding box. In this paper, we propose a tracking method by introducing the feature correlation comparison into the siamese network to increase its matching identification. We propose a way to compute location of object to improve matching performance by a correlation operation, which locates parts for solving the searching problem. The higher layer in the network can extract a lot of object information. The lower layer has many location information. To reduce error rate of the object center point, we built a siamese network that extracts the distribution and location information of target objects. As a result of the experiment, the average center error rate was less than 25%.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.4
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• pp.363-368
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• 2005

This paper proposes an LOS(line-of-sight) guidance system of a ship for path following. From the viewpoint of a control configuration, guidance is a special type of compensation algorithm that is placed in front of the controller to accomplish navigational objects. A guidance system generates a reference trajectory for trajectory tracking or path control and decides the desired velocity, position and heading angle. A control system executes commands based on a reliable guidance law during navigation. An LOS vector from the vessel to a point on the path between two way-points in straight-line navigation or a point among turning circle in turning navigation is selected, and then a heading angle is calculated to converge the desired path based on the LOS vector. The LOS guidance law is defined for the straight-line and the turning circle, respectively. The effectiveness of the suggested LOS guidance system is assured through computer simulation.

• International Journal of Control, Automation, and Systems
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• v.5 no.3
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• pp.283-294
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• 2007

In this paper, a nonlinear controller based on adaptive sliding-mode method which has a sliding surface vector including new boundizing function is proposed and applied to a two-wheeled welding mobile robot (WMR). This controller makes the welding point of WMR achieve tracking a reference point which is moving on a smooth curved welding path with a desired constant velocity. The mobile robot is considered in view of a kinematic model and a dynamic model in Cartesian coordinates. The proposed controller can overcome uncertainties and external disturbances by adaptive sliding-mode technique. To design the controller, the tracking error vector is defined, and then the sliding surface vector including new boundizing function and the adaptation laws are chosen to guarantee that the error vector converges to zero asymptotically. The stability of the dynamic system is shown through the Lyapunov method. In addition, a simple way of measuring the errors by potentiometers is introduced. The simulations and experimental results are shown to prove the effectiveness of the proposed controller.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.1
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• pp.106-111
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• 2007

In this study, we designed a digital fuzzy logic controller based on FPGA and microprocessor for MPPT of the sofar power generation system. A fuzzy algorithm to control the power tracking function of a boost converter has been built into the FPGA, and applied to the small scaled solar power generation system. The embodied controller showed a stable operation characteristic with the small output voltage ripple for the intensity change of solar radiation. This result proves that the implementation of the power tracking controller using FPGA is an effective way compared to the existing one using microprocessor.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.2
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• pp.171-177
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• 2002

The Photovoltaic systems with solar cell way Provide electrical energy to the utility/consumers, which are becoming one of the promising energy substitutes. The photovoltaic system can be classified into two types : One is the stand-alone type, and the other utility interactive one. The latter can return the generated power to the utility, but the former can't. The utility interactive systems are so valuable for peak power cut in summer season. In the photovoltaic systems the maximum power point tracking (MPPT) has been studied for the increase of the generating energy of the photovoltaic system. There are many control methods of MPPT, but a new MPPT algorithm is proposed to overcome the disadvantages of the conventional ones, and as a result the proposed method enables to improve both tracking ability and generating efficiency of photo voltaic system without DC chopper.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.11
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• pp.827-833
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• 2011

In this study, fecal nonpoint pollutant sources tracking were conducted on Ansan stream. Multiple Antibiotic Resistance Analysis (MARA) method used in this study is based on the premise that fecal bacteria derived from intestine of human or animal has each different resistance for antibiotics. First of all, a database for known sources should be established to use the method and then, an unknown sample was applied on the database to find unknown sources by statistical analysis. The Ansan stream was considered with divided condition into three parts: upper (livestock farming area), mid (old section of the city), and downstream (new section of the city) to search an environmental influence of the stream basin. As results of the statistical analysis, it could be estimated that the upper stream area was influenced by animals due to the nature of influence for the livestock farms located in this area because livestock were classified as percentages of 45.8% in 3-way method divided into livestock, pet and human. In case of midstream and downstream, the human influence was remarkable as percentage of 60% and 80%, respectively. From these results, it could be judged that the MARA method is useful in source tracking the non-point pollutant sources because the MARA results correspond to which predictable non-point pollutant sources by a field study. Also, it is expected that a more effective source tracking will be possible as establishing database of each area.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.10-18
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• 2016

The cognitive ability of humans depends much on the vision. 'Vision' refers to the sense that receives stimulus of light through eyes. 'Gaze' refers to a function of a straight line that connects the central point of the pupil and a viewpoint in the external world, and, in general, it means a straight line that connects an object that is viewed and the eyes. There are active studies on the gaze in various academic circles including 'psychology' and 'cognitive linguistics.' As a method to objectively analyze the gaze, studies on 'eye tracking' are revitalized. A device for studies on eye tracking is an 'eye tracker.' As the fields of the study expand from development and analysis of Web pages to analysis of stores, methods of traffic signal processing, transport equipment, analysis of user experiences on image contents, and marketing analysis, there occurs a greater demand for a glasses eye-tracking than that for a fixed eye tracker. This study identifies the overview and characteristics of eye tracking and presents a way for spreading studies on eye tracking.