• Journal of the Korean Wood Science and Technology
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• v.21 no.2
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• pp.57-65
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• 1993

The aim of this research was to manufacture sludge-particle board using paper sludge with wood particle and to investigate physical and mechanical properties of various sludge-particle boards, fabricated with ratios of sludge to particle of 10 to 90, 20 to 80, 30 to 70, 40 to 60 and 50 to 50(oven dry weight based). Sludge-particle boards were manufactured by urea-formaldehyde resin, 0.8 target specific gravity, and 10mm thickness. It was possible to manufacture sludge-particle board as the same processing in the present particleboard manufacturing system. This sludge-particle board have different properties as composition ratios of sludge and particle. And sludge-particle board made from 10 percent to 20 percent of sludge mixing ratio have similar mechanical properties compared with control particleboard. Especially, the sludge-particle board made from 10 percent to 40 percent mixing ratios of sludge have superior to control particleboard in internal bond, screw withdrawal holding strength and modulus of elasticity. In the case of dimensional stability, water absorption was increased and thickness swelling was decreased as increased with sludge mixing proportion. The sludge-particle board made of different mixing ratios of our laboratory design was able to concluded that there is possibility of partial substitution of wood particle materials.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.41 no.1
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• pp.25-32
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• 2004

Nowadays image processing is very useful for some field of traffic applications. The one reason is we can construct the system in a low price, the other is the improvement of hardware processing power, it can be more fast to processing the data. In traffic field, the development of image using system is interesting issue. Because it has the advantage of price of installation and it does not obstruct traffic during the installation. In this study, 1 propose the traffic monitoring system that implement on the embedded system environment. The whole system consists of two main part, one is host controller board, the other is image processing board. The part of host controller board take charge of control the total system interface of external environment, and OSD(On screen display). The part of image processing board takes charge of image input and output using video encoder and decoder, Image classification and memory control of using FPGA, control of mouse signal. And finally, for stable operation of host controller board, uC/OS-II operating system is ported on the board.

• Journal of Sensor Science and Technology
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• v.20 no.4
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• pp.272-278
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• 2011

Recently, the performance of binaural hearing aids is rapidly improved with the technology advancement of wireless communication, digital signal processing, and integrated circuit design. However, the previous hearing aids developer platforms can't be applied to binaural hearing aids developing, because it has no consideration for wireless communication and binaural hearing control. Also, the previous developer platforms are not easy to use for the algorithm development, because programming languages are limited. In this paper, we designed and implemented the open platform board for binaural hearing aids developing. The designed board can be programmed by general programming language and can be used wireless communication module. In order to verify the designed open platform board, we used the volume control algorithm using two open platform board. As a result of experiment, we verified the performance of designed and implemented open platform board that was successfully operated the binaural hearing control and the wireless communication.

• The Journal of Fisheries Business Administration
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• v.35 no.2
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• pp.1-29
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• 2004

This paper aims to understand the points which the Board of Directors of the National Federation of Fisheries Cooperatives System has proposed, and to find some improvement. This Fisheries Cooperatives previously had a single board system operating two small board rooms which became independent within the two sectors of credit and .provision in addition to the existing board of directors. This is a very unique board of directors system which is not found in cooperatives in our country nor in the business world. This change of the board of directors of the Fisheries Cooperatives is ascribed to the reorganization of the system into a completely independent division system, which operates business separately based on each sector as opposed to the previous multiple cooperatives system. However, a plural board of directors system does contribute to the improvement of managerial efficiency by strengthening the self-control of each independent business section, but deepens conflicts between its internal organizations, and brings about a reverse function which might deteriorate both the controlling power of a systematic organization and the coordinating power between sectors. This paper made an analysis of acceptors' attitudes toward the board of directors of the fisheries cooperatives system by regulating all the staff directly related to the operation of the board of directors of the fisheries cooperatives system as a group of acceptors and by selecting one hundred and fifty persons among the staff as a sample. The inquiry into acceptors' attitudes was made using questionaries, and the data for this investigation was processed and analyzed using a statistical method. The contents of this paper are composed of I. an introduction, II. the findings of the questionary investigation, III. the overall opinion for the improvement of the board of directors system, and IV. a summary and conclusion.

• Journal of the Korean Society of Safety
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• v.33 no.5
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• pp.21-27
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• 2018

The purpose of this study is to develop a SOP (Standard Operating Procedure) for a distribution board that can monitor the leakage current of a load distribution line in real time. The developed distribution board was fabricated by applying IEC 61439-1. It consists of the distribution board and an alarm device. The work process for making the distribution board was compliant with the KEMC (Korea Electrical Manufacturers Cooperative) regulations. And the AC distribution board range is 1,000 V. In addition, the voltage in DC is less than 1500 V. The distribution board receives a 3-phases and 4-wires power supply system and can supply power to the load of a maximum of 32 single or three phase distribution circuits. Also, leakage current measured on the power distribution board was used by sensors installed. The SOP of the developed distribution board consists of the installation standards for the short circuit alarm device and sensor, the surge protection device, switches and indication lamps, and other devices. The operation procedure was prepared so that each manufacturing step of the distribution board must be confirmed by the persons in charge of preparation, production, quality control and approval before moving forward to the next step.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.3
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• pp.384-393
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• 2012

Railroad signaling systems perform controlling the distance and routes between trains. Signaling methods on the wayside are to control passively the train speed by using signal flags which are installed on the wayside. ATS(Automatic Train Stop) device is used as the signaling method on the wayside in Korea. The ATS device is assistance equipment of engineers. Signal information is transmitted by combining mutual inductance between the wayside transmitter and on-board receiver. The wayside transmitter performs changing oscillation frequency according to the signal information. The on-board receiver performs controlling the train by receiving the frequency. Currently, the oscillation frequency on the on-board receiver is 78[kHz] in case of normal state. When the on-board receiver is over the wayside transmitter, the oscillation frequency is changed by capacitors of the wayside transmitter according to signal flags. In case of changing the oscillation frequency, the waveform is modified in the wayside transmitter and on-board receiver. This phenomenon is that other signals or communication frequency are included. In this paper, electric model between the wayside transmitter and on-board receiver is suggested and frequency response in the wayside transmitter and on-board receiver including other signals is estimated by the coupling coefficient. Also, the value of coupling coefficient is proposed to exclude other signals and demonstrated by using Matlab and PSpice program.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.861-872
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• 2021

This study examines the relationship between board characteristics and capital structure. Data was collected from the annual reports of listed companies in the Stock Exchange of Thailand, from 2015 to 2017, which totaled 1,264 firm-year observations. The study uses multiple regression analysis to analyses the data by using independent variables, including board size, outside directors, managerial ownership, CEO duality, frequency of board meetings, board experience, and gender to measure board characteristics and the total debt ratio for capital structure. Research findings show that the more independent the directors are, the lower the cost of debt financing is, as they control the management team more strictly about debt financing than directors with less independence do. Additionally, the results reveal that the higher the percentage of managerial ownership, the higher the level of leverage and debt financing, whereas board size and board meetings have a negative relationship to capital structure. Further research showed that firm size, growth opportunities and corporate governance rating all had a positive significant impact on capital structure. The findings of this study suggest that the presence of proper corporate governance leads to better funding mechanisms as it ensures that the company is in a better position to obtain external funding.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.473-474
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• 2010

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.6
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• pp.342-350
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• 2003

In this paper, a levitation controller for a magnetic levitation(MagLev) system is designed and implemented. The target to be controlled is PEM(permanent and electromagnet) type with 4-corners levitation which is open-loop unstable, highly non-linear and time-varying system. The digital control system consists of a VME-based CPU board, AD board, PU board, 4-Quadrant chopper, and gap sensor, accelerometer as feedback sensors. In order to estimate the velocity of the magnet, we used 2nd-order state observer with acceleration and gap signal as input and output, respectively. Using the estimated states, a state feedback control law for the plant is designed and the feedback gains are selected by using the pole-placement method. The designed controller is experimentally validated by step-type gap reference change and force disturbance test.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.11
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• pp.494-502
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• 2002

In this paper, a suspension control of a magnetic levitation(MagLev) system with flexible rail is designed and presented. The numerical modelling for the electromagnetic system to be controlled as a target plant is carried out. And dome kinds of the hardware system including CPU board, AD board, DA board, sensors, and switching power amplifier are described. Using the derived model, the stabilizing controllers, such as PID and $H_{\infty}$ controller, for the MagLev system are designed using the MATLAB toolbox. The designed controllers are validated by some experimental results as well as numerical simulations. So it is shown that $H_{\infty}$ controller can give the better performance for the plant with flexible modes than PID controller.