• Clean Technology
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• v.11 no.2
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• pp.83-90
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• 2005

This paper is about a new method of synthesis organic tanning agent (polymer, polyphenol, polyresin) and discusses their tanning property. It was found that properties of the leather manufactured with application of organic tanning agent were similar to those applied with conventional chrome tanning agent and reducing effects of Cr, T-N, COD, SS concentrations in the effluent.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.1-12
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• 2008

The aim of this study is to investigate the sensitivity evaluation of human beings in reacting to the correlated color temperature of the optical properties of white LED lighting. For the sake of this study, white light-emitting diode modules have been fabricated their correlated color temperature have been measured, test cabinets for the sensitivity evaluation have been constructed with the white LED modules, and their sensitivity reactions on the test cabinets have been evaluated and analyzed. The sensitivity reaction has been evaluated by the semantic differential method with 15 selected questions, and the reliability and the content validity of their lighting have been analyzed to 3 factors which foe the activity as the first factor, the stability as the second one, the potency as the third one, respectively. For the data analysis on the sensitivity reaction, the dependent variable is the score of the sensitivity evaluation and the independent one is the correlated color temperature of the test module. The results of this study is as follows: In the case of the sensitive evaluation on the activity and the potency in the white LED lighting compared with the fluorescent lamp, the subjects have made higher mark on $MA_3$ with 8,300[K], and in the factor of the stability, they have made higher mark on $MA_1$ with 3,800[K].

• Science of Emotion and Sensibility
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• v.9 no.4
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• pp.353-366
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• 2006

The aim of this study is to characterize the optical properties of white light-emitting diodes lighting modules and then to evaluate the sensitivity of students and teachers in reacting to the optical properties of these modules. For the sake of this study, each of 5 lighting modules was introduced to the 5 test cabinets. The 5 test cabinets were evaluated and analyzed the student and teacher's sensitivity reaction. We have selected If questions on sensitivity of the lighting and evaluated these questions with semantic differential method. To verify the reliability and objectivity of the questions, the feasibility survey was carried out by a preliminary test. As a result of the test, the sensitivities on the test cabinets were classified the 4 factors, namely, activity as the first factor, stability as the second one , potency as the third one and sensitive image as the fourth one respectively. By the evaluation of student and teacher's sensitivity on the correlated color temperature, they preferred the cabinet with the higher color temperature in view of the activity and potency. And they preferred the cabinet with the lower color temperature in view of the stability factor. In the sensitive image, they preferred the 5800K, bluish white lighting regardless of the color temperature. By the evaluation on the color rendering index, they preferred the cabinet with the higher color rendering index in view of the activity, stability and sensitive image. In the potency factor, they preferred the white lighting with the middle color rendering index.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2907-2910
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• 2003

시각장애인의 보행을 보조할 목적으로 설치된 점자보도블록은 보행방향과 정지 정보를 제공하지만, 현재 위치에 대한 정보는 제공 할 수 없어서 보행 보조물로써의 기능이 매우 제한되어 있다. 본 연구에서는 최근 IT 기술중 하나인 RFID(Radio Frequency Identification)를 내장한 새로운 개념의 점자보도블록과 이를 활용하여 보행을 유도할 수 있는 시스템을 제안하고자 한다. 점자보도블록에는 RFID 태그와 안테나를 삽입하여 현재 위치에 대한 정보를 저장하며, 백색지팡이에는 이 정보를 읽어 들이기 위한 리더기를 설치한다. 현재위치에 대한 정보는 PDA로 전송되어 해당되는 음성정보를 시각장애인에게 전달하게 된다. 제안된 시스템을 통해 시각장애인은 타인의 도움 없이 현재 자신이 위치한 곳에 대한 정보를 얻고, 올바른 곳으로 보행중인지를 판단할 수 있게 되므로, 시각장애인의 보행권과 사회활동권등 복지 증진에 효과가 있을 것이다.

• Journal of Sensor Science and Technology
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• v.8 no.1
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• pp.69-79
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• 1999

The research and implementation was preformed on high-resolution CCTV camera with CCD exclusive DSP conventional analog signal processor CCTV camera has its limit on auto exposure(AE), auto white balance(AWB), back light compensation(BLC) processing, severe distortion and noise of image, manual control parameter setting, etc. In our study, to resolve the problems in conventional CCTV camera, we made it possible to control AE, AWB, BLC automatically by the use of the DSP, which are used exclusively in the CCD camera produced domestically, and the microcontroller. And we utilized the function of screen display of microcontroller for the user-friendly interface to control CCD camera. And the electronic variable resister(EVR) was used to avoid setting parameters manually in the level of manufacturing process. As the result, It became possible to control parameters of the camera by program. And the cost-down effect was accomplished by improving the reliability of parameter values and reducing the efforts in setting parameters.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1C
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• pp.15-20
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• 2009

For perpendicular magnetic recording (PMR) channels, noise-predictive maximum likelihood (NPML) detection method has been used. But, it is hard to expect improving the performance when the bit density is increased. Hence, we exploit the coding methods which has good performance. In this paper, we show the performance of the recursive systematic convolutional (RSC) codes with turbo-equalization method with different channel bit densities. The noise model is 80% jitter noise and 20% AWGN.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1044-1053
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• 2010

Transmitting correct train control information is important in a train control system which demands safety. The train control information includes the maximum speed of trains, position of preceding trains, incline of tracks and curve sections etc. A radio frequency-communication based train control system is influenced by the noise and interference because the train control information is transmitted by wireless between a on-board system and wayside system. The radio frequency-communication based train control system is a mobile communication system due to moving trains. The inter symbol interference(ISI) occurs by the multipath fading in the mobile ommunication system. As signal-to-noise ratio(SNR) is decreased by the ISI, the train control information is not received correctly. In case of tunnel section, numerous reflected waves exist. Therefore, the power density of receiver is decreased by difference among the received times, magnitudes, phases through the multipath. So, the train suddenly is stopped by the fail-safe operation in the train control system on account of decreasing the power density of receiver. In this paper, a line of sight model-(Additive White Gaussian noise(AWGN) channel), rayleigh and rician fading model are presented. Probability density functions which are related to the SNR are derived from the models. The fading phenomenon severely occurs as a result of analyzing the probability density functions. So, the space diversity method is used in order to reduce the fading effect and it is demonstrated by using Matlab program.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.1
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• pp.85-93
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• 2007

In case that multichannel blind deconvolution (MBD) applies to signals of which autocorrelation has a high level, separated signals are temporally whitened by diagonal elements of a separation filter matrix. In order to reduce this distortion, the algorithms, which are based on either constraining diagonal elements of a separation filter matrix or estimating a separation filter matrix by using linear prediction residual signals, are presented. Still, some problems are generated in these methods, when we separate reverberation of signals themselves or interference signals from mixed signals. To solve these problems, this paper proposes the multichannel blind deconvolution method which divides processing procedure into the stage to separate interference signals and the stage to eliminate a reverberation of signals themselves. In simulation results, we confirm that the proposed algorithm can solve the problems.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.405-409
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• 2009

In this paper, the effects of LLR (Log-Likelihood Ratio) approximation on LDPC (Low-Density Parity-Check) decoder performance are analyzed, and optimal design conditions of LDPC decoder are derived. The min-sum LDPC decoding algorithm which is based on an approximation of LLR sum-product algorithm is modeled and simulated by MATLAB, and it is analyzed that the effects of LLR approximation bit-width and maximum iteration cycles on the bit error rate (BER) performance of LDCP decoder. The parity check matrix for IEEE 802.11n standard which has block length of 1,944 bits and code rate of 1/2 is used, and AWGN channel with QPSK modulation is assumed. The simulation results show that optimal BER performance is achieved for 7 iteration cycles and LLR bit-width of (7,5).

• Food Engineering Progress
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• v.14 no.3
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• pp.193-201
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• 2010

The aim of this study was to analyse the quality of Yukwa puffed by using a vacuum puffing machine and compare to deep-fried Yukwa. The effect of vacuum puffing condition including heating temperature(100-${160^{\circ}C}$), preheating time(0-8 min) and vacuum puffing time(5-20 min) on physical and microstructure characteristics of the Yukwa was investigated. Vacuum puffed Yukwa at ${100^{\circ}C}$ heating temperature, 6 min preheating time and 10 min puffing time had highest value in volumetric expansion ratio(10.04) and lowest value in bulk density(0.15 g/$cm^{3}$). The breaking strength showed the lowest value of 140 g/$cm^{3}$ in vacuum puffing Yukwa at ${100^{\circ}C}$ heating temperature, 6 min preheating time and 15 min puffing time. The Yukwa puffed with the vacuum puffing machine at ${100^{\circ}C}$ heating temperature, 6 min preheating time and 15 min puffing time had the higher value of bulk density and the lower value of volumetric expansion ratio than those of deep-fried Yukwa. Increasing preheating time and vacuum puffing time caused an increase in white and an decrease in yellowness. The vacuum-puffed Yukwa exhibited smaller and uniform cell structure, while deep-fried Yukwa exhibited apparently in larger pores inside and smaller pores near the surface layer. The optimum condition of vacuum puffing machine for the production of vacuum-puffing Yukwa was ${120^{\circ}C}$ heating temperature, 4 min preheating time and 5 min puffing time.