• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.1
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• pp.83-92
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• 2010

Emergence of high-resolution digital aerial cameras and airborne laser scanners have made innovative progress in photogrammetry and spatial information technology. The purpose of this study is to generate true orthoimage by recovering occlusion areas. The orthoimages were generated patch-based transformation. The occlusion areas were mutually corrected by using multiple aerial images. This study proposed a novel method of building roof based orthoimage generation and an effective method of occlusion area detection and recovery. The proposed methods could be efficient to generate true orthoimages in urban areas where occlusion areas are problematic.

• Korean Journal of Computational Design and Engineering
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• v.21 no.1
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• pp.9-19
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• 2016

Applying human engineering simulation to analyzing work capability and movements of operators during manufacturing is highly demanded. However, difficulty in modeling digital human required for simulation makes engineers to be reluctant to utilize human simulation for their tasks. This paper addresses such problem on human engineering simulation by developing the technology to automatize human modeling with multiple Kinects at different depths. The Kinects enable us to acquire the movements of digital human which are essential data for implementing human engineering simulation. In this paper, we present a system for modeling automation of digital human. Especially, the system provides a way of generating the digital model of workers' movement and position using multiple Kinects which cannot be generated by single Kinect. Lastly, we verify the effects of the developed system in terms of modeling time and accuracy by applying the system to four different scenarios. In conclusion, the proposed system makes it possible to generate the digital human model easily and reduce costs and time for human engineering simulation.

• IEIE Transactions on Smart Processing and Computing
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• v.1 no.1
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• pp.8-16
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• 2012

An image obtained from a low light environment results in a low-exposure problem caused by non-ideal camera settings, i.e. aperture size and shutter speed. Of particular note, the multiple color-filter aperture (MCA) system inherently suffers from low-exposure problems and performance degradation in its image classification and registration processes due to its finite size of the apertures. In this context, this paper presents a novel method for the color enhancement of low-exposure images and its application to color shift model-based MCA system for image refocusing. Although various histogram equalization (HE) approaches have been proposed, they tend to distort the color information of the processed image due to the range limits of the histogram. The proposed color enhancement algorithm enhances the global brightness by analyzing the basic cause of the low-exposure phenomenon, and then compensates for the contrast degradation artifacts by using an adaptive histogram specification. We also apply the proposed algorithm to the preprocessing step of the refocusing technique in the MCA system to enhance the color image. The experimental results confirm that the proposed method can enhance the contrast of any low-exposure color image acquired by a conventional camera, and is suitable for commercial low-cost, high-quality imaging devices, such as consumer-grade camcorders, real-time 3D reconstruction systems, digital, and computational cameras.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.6 no.1
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• pp.13-24
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• 1988

The determination of three-dimensional positions on a circular or cylindrical surface covers a variety of applications. As an example, consider the monitoring of structures, which is an important topic in the broad category of deformation analysis. The use of convergent photography in determination of these positions has the many advantages over survey based procedures. This paper illustrates results from bundle adjustments derived from convergent photography of a cylindrical object, with both metric and non-metric cameras utilized in the test. In addition to standard error comparisons resulting from the error analysis provided by the bundle adjustments, object space coordinates resulting from metric and non-metric camera network geometries will also be compared.

• Journal of the Korea Safety Management & Science
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• v.12 no.4
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• pp.81-86
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• 2010

Despite the importance of cycling postures during cycling performances, there has been a very little research investigating cycling postures and pedaling rate for particularly concerning domestic cyclists. The aim of this study was to analyze correlations and effects between cycling postures and pedaling rate in track cycling. Twelve male racing cyclists (six racing and university cyclists) participated in this research. For this study, seven infrared cameras (Qualisys ProReflex MCU-240s) were used for collecting data and these were processed via QTM (Qualisys Tracker Manager) software. It appeared that pedaling rate had correlations with regard to a shoulder angle (R=-.601) and displacement between shoulder joints(R= -.637), but a knee (R=-.601) and ankle angle (R=.667). Moreover, two multiple regression equations of pedaling rate for cycling postures were significant and R2 of the first order equation y (pedaling rate) = 0.039x (knee angle) - 1.068 was less than the second order equation y = 0.006x2 - 1.287x + 69.674. In conclusion, cycling postures affected the pedaling rate. Further study should be researched on postures in relation to air resistance in a wind tunnel.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.12C
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• pp.1175-1180
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• 2005

We present a vision-based hand gesture detection and tracking system. Most conventional hand gesture recognition systems utilize a simpler method for hand detection such as background subtractions with assumed static observation conditions and those methods are not robust against camera motions, illumination changes, and so on. Therefore, we propose a statistical method to recognize and detect hand regions in images using geometrical structures. Also, Our hand tracking system employs multiple cameras to reduce occlusion problems and non-synchronous multiple observations enhance system scalability. In this experiment, the proposed method has recognition rate of $99.28\%$ that shows more improved $3.91\%$ than the conventional appearance method.

• Journal of Hydrogen and New Energy
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• v.17 no.2
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• pp.193-203
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• 2006

A high-speed and initial helium jet flow has been analyzed by a developed four-dimensional digital speckle tomography. Multiple high-speed cameras have been used to capture movements of speckles in multiple angles of view simultaneously because a shape of a nozzle for the jet flow is asymmetric and the initial jet flow is fast and unsteady. The speckle movements between no flow and helium jet flow from the asymmetric nozzle controlled by a solenoid valve have been obtained by a cross-correlation tracking method so that those distances can be transferred to deflection angles of laser rays for density gradients. The four-dimensional density fields for the high-speed helium jet flow have been reconstructed from the deflection angles by a developed real-time tomography method.

• The Research Journal of the Costume Culture
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• v.22 no.4
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• pp.632-639
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• 2014

The purpose of this study was to verify the effect of drive swing on multiple functional wear wearing in golf. The subjects were 6 men ($22.67{\pm}0.82$ yrs, $175.42{\pm}3.42cm$, $78.75{\pm}4.78kg$), who had career each with at least 8 yers golf experience with right-hander. For kinemetical analysis, this study used equipments with 7 motion capture cameras (300Hz) and analysis program (Nexus1.5). The total time of the club head, displacement magnitude of the COM and swing plane were compared of according to functional wear wearing and non-weraing during golf drive swing. The results of the study are as follows. The total time of the club on wearing ($2.18{\pm}0.06sec$) was faster than non-wearing ($2.52{\pm}0.15sec$). Displacement magnitude of the COM on wearing ($4.06{\pm}0.67cm$) was shorter than non-wearing ($5.79{\pm}0.72cm$). Also, swing plane was found to be significantly different of 3 phase excepted BST-DS (back swing top-down swing) phase. AD-BST (address-back swing top) phase on wearing ($13.86{\pm}3.08cm$) decrease more than non-wearing ($20.82{\pm}3.99cm$), DS-IP (down swing-impact) phase on wearing ($6.25{\pm}1.35cm$) decrease more than non-wearing ($7.18{\pm}1.52cm$) and IP-FT (impact-follow though) phase on wearing ($7.93{\pm}2.09cm$) decrease more than non-wearing($9.68{\pm}2.02cm$). The multiple functional wear wearing was contribution to come close for one-plane, a long with consistency and accuracy on golf drive swing.

• Journal of Digital Contents Society
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• v.18 no.6
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• pp.1009-1015
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• 2017

Recently, video surveillance is becoming more and more common as many camera are installed due to crime, terrorism, traffic and security. And systems that control cameras are becoming increasingly general. Video input from the installed camera is monitored by the multiscreen at the central control center, it is essential to simultaneously monitor multiscreen in real-time to quickly respond to situations or dangers. However, monitoring of multiscreen in a mobile environment such as a smart phone is not applied to hardware specifications or network bandwidth problems. For resolving these problems, in this paper, we propose a system that can monitor multiscreen in real-time in mobile-phone environment. We reconstruct the desired multiscreen through transcoding, it is possible to monitor continuously video streaming of multiple cameras, and to have the advantage of being mobile in mobile-phone environment.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1344-1368
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• 2007

The Advanced countries including Japan, USA and European countries are adopting automatic system(e.g., auto-measurement using CCD camera) for measuring pantograph sliding plate and wheel abrasion to minimize manpower for E.M.U(Electric Multiple Unit) inspection and maintenance as part of management rationalization of railroad Corporation since late 1980's. In Korea, as part of scheme of business rationalization, automatic system for measuring pantograph sliding plate and wheel abrasion started to draw industry attention since late 1990s, and the system started to be installed in newly built depots of Korea Railroad Corporation since 2002. This study hopefully provides the base for realizing business rationalization and applying the advanced technology developed by Korea, the country of powerful IT basis, to overseas railroad organizations by examining automatic system for measuring pantograph sliding plate abrasion using existing CCD cameras produced domestically and in foreign countries to study cases(organizations in Korea) for improvement of measurement, management and inspection of pantograph sliding plate abrasion using CCD cameras with new cutting-edge technology; and by applying the study result to railroad organizations in metropolitan areas in Korea.