• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.10
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• pp.783-789
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• 2020

This paper proposes a new method for vision-based navigation using semantically segmented aerial images. Vision-based navigation can reinforce the vulnerability of the GPS/INS integrated navigation system. However, due to the visual and temporal difference between the aerial image and the database image, the existing image matching algorithms have difficulties being applied to aerial navigation problems. For this reason, this paper proposes a suitable matching method for the flight composed of navigational feature extraction through semantic segmentation followed by template matching. The proposed method shows excellent performance in simulation and even flight situations.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.53-59
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• 2007

A navigation system for virtual environments using low-qualify HMD(head mounted display) must quantize images when the system presents true-color image with restricted number of colors. Such navigation system quantizes an image by using fixed palette. If the system represents an image by using a variable palette which is made considering a region around the viewpoint then user can perceive a virtual environments more vividly because human visual system is sensitive to the colors variation in the region around the viewpoint. In this paper we propose a color quantization algorithm that quantize a region around the viewpoint more finely than other regions at each variation of viewpoint for virtual environments navigation system and compose virtual environments navigation system using proposed algorithm. The system quantizes an image at each variation of viewpoint and shows a quantized image to user through HMD. We tested user preferences for our proposed system and the results show that users preferred our system.

• Journal of Navigation and Port Research
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• v.28 no.9
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• pp.791-798
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• 2004

Since world container throughput continues to grow, the main issues facing decision-makers at port container terminals are how to expand the existing container terminals and construct new container terminals. Simulations can be used in the decision making process tools due to its ease and ability to reflect the real world system. The object-oriented approach provides for both reusability and modularity that best fits these requirements. In this paper, the object-oriented approach to modeling and simulating general container terminals is presented. Simulation tools based on Visual C++ provide a user-friendly input and output environment through the use of an object class-library. This paper also presents the case study of a simulation of a real container terminal i. Pusan, Korea

• Journal of Advanced Navigation Technology
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• v.15 no.3
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• pp.471-477
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• 2011

A wide distribution of CCTV cameras in many public areas can be used not only for video surveillance systems but also for preserving fire occurrence. A proposed approach is based on visual information through a static camera. Video sequences are analyzed to find fire candidates and then spatial analyses procedure for detected fire-like color foreground is carried out. If spatial and temporal variances changes rapidly and close to fire motion, fire candidate is considered as fire.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.06a
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• pp.93-105
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• 2000

This paper describes prototype Virtual Reality Ship Simulator (VRSS) that we have recently developed next-generation training equipment based on the virtual reality (VR) technology. The inherent defects of conventional ship simulators are enormous costs and difficult system upgrade due to the system construction, such as large mock-up bridge system, wide visual presentations, In this paper, to cope with those problems, we explored VR technology that can give realistic environments in a virtual world. Then we constructed prototype VRSS system, which is, consists of PC-based human sensors, and Databases set having 3D object models and coefficients of Head Related Transfer Functions (HRTFs). 3D-WEBMASTER authoring tool was used as Virtual Reality Modeling Language (VRML). Using the VRSS system, we constructed Port an Passage Simulator for the harbor of INCHON in Korea, and Ship and Sea State Simulator for an arbitrary given sea environmental states by user. Through many simulation tests, we testified the efficiency of developed prototype VRSS by subject assessment with five participants. Then, we present results on the simulation experiments and conclude with discussion of evaluation results.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.08a
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• pp.77-86
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• 2004

Since world container throughput continues to grow, the main issues facing decision-makers at port container terminals are how to expand the existing container terminals and construct new container terminals. Simulations can be used in the decision making process tools due to its ease and ability to reflect the real world system. The object-oriented approach provides for both reusability and modularity that best fits these requirements. In this paper, the object-oriented approach to modeling and simulating general container terminals is presented. Simulation tools based on Visual C++ provide a user-friendly input and output environment through the use of an object class-library. This paper also presents the case study of a simulation of a real container terminal in Pusan, Korea.

• Journal of the Korean Institute of Navigation
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• v.6 no.1
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• pp.61-72
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• 1982

As it is well-known, in recent years the Kalman filter has been extensively used in the engineering field. The authors tried to apply the extended Kalman filter for optimal estimation of ship's positiion which is fixed by simultaneous visual (or radio) bearings to two known locations. In practical piloting, bearings are generally measured intermittently, so in this case the original Kalman filter can not be applied because of the long sampling time. In this paper, the extended Kalman filter is revised in order to be used in such an unfavorable case, adn the Digital simulation is conducted by using the revised extended Kalman filter under various noise conditiions. Good results have been obtaiend and effectiveness of the proposed filter has been confirmed.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.948-950
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• 1999

In this paper, a monitoring system is desigend for a GPS/INS integration system. The function of the monitoring system is to acquire real-time data from system and displayed them. The monitoring system supervises the operation of navigation system. Visual C++ was used in the implementation. The performance of the monitoring system was verified through a real-time test for a GPS/INS Integration system which is composed of a GPS Receiver. IMU(Inertial Measurement Unit), NCU (Navigation Computer Unit)

• Journal of Advanced Navigation Technology
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• v.13 no.6
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• pp.1011-1016
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• 2009

In this paper, we propose the method of fire detection. A wide distribution of CCTV cameras (Closed Circuit Television) in many public areas can be used not only for video surveillance systems but also for detecting fire occurrence. A proposed approach is based on visual information through a static camera. Video sequences are analyzed to find fire candidates and then spatial analyses procedure for detected fire-like color foreground is carried out. From the simulation results, our method showed the best performance when spatial and temporal fire candidates changes rapidly and close to fire motion.

• Journal of Navigation and Port Research
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• v.26 no.4
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• pp.449-453
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• 2002

Recently a ship manoeuvring simulator has been developed by Korea Maritime University. We are desiring to apply the movement of wave to the visual scene of sea state in the simulator. This paper discussed the calculation method and visualization simulation of three dimensional sea state using OpenGL API, and the possibility to apply calculation result to the simulator.