• The Journal of Korea Robotics Society
• /
• v.15 no.1
• /
• pp.55-61
• /
• 2020

Getting on and off an elevator is one of the most important parts for multi-floor navigation of a mobile robot. In this study, we proposed the method for the pose recognition of elevator doors, safe path planning, and motion estimation of a robot using RGB-D sensors in order to safely get on and off the elevator. The accurate pose of the elevator doors is recognized using a particle filter algorithm. After the elevator door is open, the robot builds an occupancy grid map including the internal environments of the elevator to generate a safe path. The safe path prevents collision with obstacles in the elevator. While the robot gets on and off the elevator, the robot uses the optical flow algorithm of the floor image to detect the state that the robot cannot move due to an elevator door sill. The experimental results in various experiments show that the proposed method enables the robot to get on and off the elevator safely.

• Journal of Advanced Navigation Technology
• /
• v.13 no.5
• /
• pp.773-780
• /
• 2009

This study proposed a face region detection algorithm using fuzzy inference of pixel hue and intensity. The proposed algorithm is composed of light compensate and face detection. The light compensation process performs calibration for the change of light. The face detection process evaluates similarity by generating membership functions using as feature parameters hue and intensity calculated from 20 skin color models. From the extracted face region candidate, the eyes were detected with element C of color model CMY, and the mouth was detected with element Q of color model YIQ, the face region was detected based on the knowledge of an ordinary face. The result of experiment are conducted with frontal face color images of face as input images, the method detected the face region regardless of the position and size of face images.

• Journal of Advanced Navigation Technology
• /
• v.16 no.3
• /
• pp.518-525
• /
• 2012

The modulation transfer function is generally used as a method to estimate the characteristics of this kind of optical system because it cannot reappear or implement image of the object perfect. By the way, it is difficult to assess the optical system with existing MTF method since the reaction between diffraction and aberration of aperture is very complicate if the aberration is very small. The MTF has to be calculated considering the numerical aperture, defocusing, OPD and phase difference. We validate its feasibility using bessel function as an estimating method, and then realize it through illustration in this paper.

• Journal of Advanced Navigation Technology
• /
• v.13 no.1
• /
• pp.62-67
• /
• 2009

The demand for high performance computer grows to solve large linear systems of equations in such engineering fields - circuit simulation for VLSI design, image processing, structural engineering, aerodynamics, etc. Many various parallel processing systems have been proposed and manufactured to satisfy the demand. The properties of linear system determine what algorithm is proper to solve the problem. Direct methods or iterative methods can be used for solving the problem. In this paper, an intelligent parallel iterative method for solving linear systems of equations with large sparse matrices is proposed and its efficiency is proved through simulation.

• Journal of Advanced Navigation Technology
• /
• v.13 no.1
• /
• pp.142-150
• /
• 2009

It is very important to generate a simplified model from a complex 3D character in computer game. We propose a new method of extracting feature lines from a 3D game character. Given an unstructured 3D character model containing texture information, we use model feature map (MFM), which is a 2D map that abstracts the variation of texture and curvature in the 3D character model. The MFM is created from both a texture map and a curvature map, which are produced separately by edge-detection to locate line features. The MFM can be edited interactively using standard image-processing tools. We demonstrate the technique on several data sets, including, but not limited to facial character.

• Journal of Advanced Navigation Technology
• /
• v.18 no.3
• /
• pp.242-247
• /
• 2014

The advancement of touch user interface technology is mostly due to the debut and success of the new user experience (UX), the iPhone. The introduction of Apple's iPhone especially made possible for the user experience to break away from the traditional input device of the mouse and keyboard. It is advancing from the current 3rd generation touch interface technology into the 4th generation non-touch user interface technology. This paper will present a non-touch interaction technology that allows interaction in a three dimensional setting through 3-D space touch. It will analyze current technologies and future emerging technologies.

• Journal of Navigation and Port Research
• /
• v.44 no.2
• /
• pp.110-118
• /
• 2020

With the expansion of the shipping and port logistics industry in the 21st century, the traffic density is continuously increased because of the increase in volumes of world sea freight and fleets, as well as the increase in the causes of potential marine accidents, such as ship collisions and stranding. Accordingly, the International Maritime Organization (IMO) has requested that the installation and operation of VTS should be applied in areas with high risk of marine traffic, and the request should be included as one of the Safety of Life at Sea (SOLAS) regulations. In this paper, the fundamental requirements of the radar system for vessel traffic services were analyzed and the analyzing factors were based on the IALA guideline.s This paper also includes results for the requirement and recommendation analysis on detection distance, target separation, and the target position accuracy of X-band radar. Also, to check if it satisfies the requirement of detection distance, range and azimuth separation of small point targets, and target position accuracy from the IALA guidelines, the test was conducted through the radar image acquired at the VTS center, and hence, the validity of the technical performance requirements was confirmed.

• Journal of Advanced Navigation Technology
• /
• v.16 no.2
• /
• pp.375-385
• /
• 2012

The fingerprint is the identity authentication method which is representative uses biometrics. Compared with password methods there is a feature where the dangerousness of embezzling or lossing is few. With like these features using the fingerprint in OTP creations. In this paper, we introduce the developed prototype of OTP system using fingerprint. And the overcome method of OTP system's demerit using fingerprint which extracts few minutiae points into a whole fingerprint image is proposed. A few minutiae points wasn't generated many encryption key for OTP session. The proposed method is overlaid the same fingerprint simply and added many minutiae points as biased overlaid fingerprints. Hence the security of OTP using fingerprint and the randomness over password-guessing are strengthened.

• Journal of Advanced Navigation Technology
• /
• v.18 no.4
• /
• pp.387-392
• /
• 2014

Recently, various research for intelligent video surveillance system have been proposed, but the existing monitoring systems are inefficient because all of situational awareness is judged by the human. In this paper, shadow removal based moving object tracking method is proposed using the chromaticity and entropy image. The background subtraction model, effective in the context awareness environment, has been applied for moving object detection. After detecting the region of moving object, the shadow candidate region has been estimated and removed by RGB based chromaticity and minimum cross entropy images. For the validity of the proposed method, the highway video is used to experiment. Some experiments are conducted so as to verify the proposed method, and as a result, shadow removal and moving object tracking are well performed.

• Journal of Navigation and Port Research
• /
• v.34 no.6
• /
• pp.429-434
• /
• 2010

The experimental study of the hull surface roughness on a developing turbulent boundary layer which exposed to a variety of operating environments were investigated by performing particle image velocimetry(PIV) in a circulating water channel. The Reynolds number based on the width of roughness was about Re=1000. the roughness elements used were periodically arranged two-dimensionally. the flow visualization, time-mean velocity fields and vorticity fields to measure the flow characteristics were obtained. The investigation shows that the vortex generation and its progress inside the walls. And the center of the vortex was located at the middle of the height of the surface roughness.