• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.1011-1012
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• 2008

Image quality analysis has been carried out for both monochrome and colour print images obtained by a calibrated low-end scanner. The analysis method is based upon ISO13660 for monochrome images and additional criteria for colour quality that we have defined. We have compared performance of the calibrated scanner with that of a high-end spectrophotometer in terms of several aspects such as line and large area. They have provided similar results without significant discrepancy.

• Korean Journal of Remote Sensing
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• v.27 no.5
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• pp.573-586
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• 2011

The MTF(modulation transfer function) is one of parameters to evaluate the performance of imaging systems. Also, it can be used to restore information that is lost by a harsh space environment (radioactivity, extreme cold/heat condition and electromagnetic field etc.), atmospheric effects and falloff of system performance etc. This paper evaluated the MTF values of images taken by DubaiSat-1 satellite which was launched in 2009 by EIAST(Emirates Institute for Advanced Science and Technology) and Satrec Initiative. Generally, the MTF was assessed using various methods such as a point source method and a knife-edge method. This paper used the slanted-edge method. The slantededge method is the ISO 12233 standard for the MTF measurement of electronic still-picture cameras. The method is adapted to estimate the MTF values of line-scanning telescopes. After assessing the MTF, we performed the MTF compensation by generating a MTF convolution kernel based on the PSF(point spread function) with image denoising to enhance the image quality.

• Journal of the Institute of Convergence Signal Processing
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• v.7 no.1
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• pp.17-23
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• 2006

In recent years, RFID has received much attention because of spread usage in industrial applications including factory, material flow, logistics and defense areas. However, there is only CRC-16 for error detection in ISO/IEC 18000-6 Protocols prepared for 860-960 MHz RFID, high error rates are expected in cases of high level of security and noisy envirionment. In this paper, we propose a usage of convolution code as a method for satisfying the high level of security requirement and system error performance.'1'he signal control function is implemented in a microprocessor with RF modulation and the convolutional encoding and Viterbi decoding are implemented in an FPGA chip.'The frame error rates are measured with and without convolution coding under the channel conditions of line-of- sight and non line-of-sight, respectively.

• Communications for Statistical Applications and Methods
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• v.11 no.1
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• pp.21-30
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• 2004

Often the accuracy is not adequate as a performance measure of classifiers when costs are different for different prediction errors. ROC and cost graphs can be used in such case to compare and identify cost-sensitive classifiers. We extend ROC and cost graphs so that they can be used when more general cost matrix is given, where not only misclassifications but correct classifications also incur penalties.

• Journal of Digital Convergence
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• v.13 no.5
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• pp.169-176
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• 2015

Virtual Private Network is a method which can use as a private network using private line. The quality of security of virtual private network is influenced by security auditability, cryptographic support, user data protection, access control, etc., and efficiency is influenced by throughput, latency, the number of cession, etc. In this paper, we constructed a evaluation model based on CC(ISO/IEC 15408) and the quality evaluation standard ISO/IEC 25000 series to evaluate the quality level about efficiency with security performance of virtual private network. We think that this study will contribute to construct the system which can evaluate the quality of virtual private network based on CC and ISO quality evaluation standard.

• Journal of Digital Convergence
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• v.11 no.7
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• pp.201-207
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• 2013

The chirp signaling has been mainly used in radar systems due to its good correlation characteristics, and nowadays it is applied to real time locating system(RTLS). The RTLS with chirp signaling was chosen as a standard such as ISO/IEC 24730-5 and IEEE 802.15.4a. In this paper, the performance of a real time locating system with chirp signaling was evaluated and simulated with relative distance error rates. We considered three cases of S/I = -30[dB], -20[dB], and -10[dB] with Rician factor K=10 and K=20. The performance was enhanced with K factor improvement by 25%, 27% and 50% for respective three cases of S/I. As results, in case of S/I < -20[dB], the minimum signal power is required for performance improvement even though the line of sight component is helpful. And also, in case of S/I ${\geq}$ -20[dB], as the line of sight component is stronger the better performance is obtained.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.2A
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• pp.119-127
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• 2012

In this paper a super-resolution time delay estimation algorithm is developed for real-time locating systems (RTLSs) that employ a direct-sequence spread spectrum technique, along with its performance analysis in multipath environments. The classical correlation method provides relatively good performance in line-of-sight (LOS) environments but its performance seriously degrades in multipath environments, especially when signals are spaced closer than a PN chip. Therefore we shall develop a super-resolution time delay estimation algorithm that may estimate the time delays of multipath signals even in closely spaced multipath environments using the MUSIC algorithm for direction-of-arrival estimation and analyze its performance by applying the algorithm to the ISO/IEC 24730-2.1 RTLS system. 

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.9
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• pp.2209-2215
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• 2014

This paper presents, a deinterlacing method by improving the Direction-Oriented Interpolation (DOI) technique. The technique is considered to be a very strong tool for intrafield-based deinterlacing. However, DOI has some problems such as long processing time, wrong edge detection in periodic pattern. To remedy this problem, we replace the full search in DOI by a two-step search to reduce processing time and introduces two additional processes to improve image quality. In the proposed method, the spatial direction vectors (SDVs) misread data are reconsidered to prevent them utilizing in the next interpolation step, resulting in an accurate deinterlacing method. We conduct experiments with ISO experimental images to compare the proposed method with the existing methods including line evarage (LA), edge-based line averaging (ELA), DOI, selective deinterlacing algorithm (SDA). Experimental results show the proposed method gives better performance in objective and subjective quality than existing deinterlacing methods.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.9-17
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• 1994

In this study, a shifting algorithm of CVT was suggested for the two(2) driving modes : (1) power mode and (2) economy mode. Shifting algorithm must be obtained to make the engine run on the optimum operating line for the desired performance of the vehicle. Optimum operating lines of the engine were obtained by connecting the shortest way of the iso-power lines for the power mode and by connecting the shortest way of the BSFC curves for the economy mode. Also dynamic model of CVT vehicle was derived considering the throttle and the brake operation. By using the shifting algorithm and the CVT vehicle model, numerical simulations were performed to estimate the performance of CVT. Simulation results showed that comparing the performance of the conventional 4-speed automatic transmission, acceleration performance of the CVT vehicle was almost same with the AT vehicle for the power mode and the fuel economy of CVT was 14% superior than that of AT for the economy mode.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.9
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• pp.9-17
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• 1993

There are multiple controllers (PLC. LOOP Controller ) which are operating in product line and fabrication line. In those lines, it is necessary to connect various multilple controllers with integrity and coordination. The ways to connect those devices are specified by ISO network standard. In this paper, real time network is designed and implemented for factory automation at lowest possible cost that meets the small and middle size MINI-MAP specifications. Network performance is evaluated by simulation method on data link layer implemented interfacing modules has efficiency in throughput by reducing processing time. The system designed in this paper can be also applied to the field of distributed systems for real time processing.