• Explosives and Blasting
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• v.39 no.2
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• pp.27-36
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• 2021

Recently, the demand for demolition for the unnecessary steel frame structure is increasing due to deterioration and unsatisfactory functional conditions and the major highlights of demolition issues. This execution case was intended to describe an application of the felling method as one about the suggested method for explosive demolition method of ore bin and coke bin facilities, which were steel frame structures. And we used the charging container for blast cutting of the steel frame structure. As a result of the explosive demolition, the ore bin and coke bin had collapsed precisely according to the estimated direction. And the explosive demolition was completed without causing any damage to surrounding facilities.

• Journal of Biosystems Engineering
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• v.33 no.3
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• pp.167-172
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• 2008

The objective of this study was to investigate the adequate storage method that was able to maintain the high quality of rough rice according to storage methods and period. The quality change of the rough rice during the storage period was evaluated by storage method such as cooling bin using winter cold air, ordinary temperature bin, freezing, refrigeration and indoor storage. Moisture content, brown rice whiteness, hardness, crack ratio and germination ratio were measured in this study. Moisture content of rough rice stored in cooling bin using winter cold air and ordinary temperature bin were decreased by 0.07% and 0.42%, respectively, which were lower than the other storage method. The hardness of brown rice increased in order of storage method such as winter cooling bin, normal bin, freezing storage, refrigeration storage and indoor storage. Crack ratio by indoor and ordinary temperature bin storage were increased by 2.68% and 3.63%, respectively, whereas cooling bin using winter cold air, refrigeration and freezing storage showed below 1.0%. The highest germination rate was found in cooling bin using winter cold air. As a result, cooling bin using winter cold air can be evaluated for the adequate storage method of rough rice.

• Current Optics and Photonics
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• v.1 no.2
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• pp.157-162
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• 2017

In large liquid crystal displays, the image quality in an oblique viewing direction is a crucial issue. From this perspective, 8-domain polymer-stabilized vertical alignment (PS-VA) mode has been developed to suppress the color shift in oblique viewing directions, compared to that in 4-domain PS-VA mode. To realize the 8-domain PS-VA, the four domains in a pixel are each divided into two regions, such that applying different electric potentials result in different tilt angles in these two regions, while keeping four azimuthal directions in each domain. However, applying different voltages in a pixel causes drawbacks, such as requiring additional processes to construct a capacitor and a transistor, which will further reduce the aperture ratio. Here we propose a different approach to form the 8-domain, by controlling surface polar anchoring energy and the width of patterned electrodes in two regions of a pixel. As a result, the gamma-distortion index (GDI), measured at an azimuthal angle of $0^{\circ}$, is reduced by about 23% and 8%, compared to that of a conventional 4-domain at polar angles of $30^{\circ}$ and $60^{\circ}$ respectively.

• Current Optics and Photonics
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• v.3 no.1
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• pp.66-71
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• 2019

Application of liquid crystal (LC) materials to a flexible device is challenging because the bending of LC displays easily causes change in thickness of the LC layer and orientation of LCs, resulting in deterioration in a displayed image quality. In this work, we demonstrate a prototype device combining a flexible polymer substrate and an optically isotropic LC-polymer composite in which the device consists of interdigitated in-plane switching electrodes deposited on a flexible colorless polyimide substrate and the composite consisting of nano-sized LC droplets in a polymer matrix. The device can keep good electro-optic characteristics even when it is in a bending state because the LC orientation is not disturbed in both voltage-off and -on states. The proposed device shows a high potential to be applicable for future flexible LC devices.

• Journal of Biosystems Engineering
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• v.24 no.4
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• pp.359-364
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• 1999

A theoretical model was developed to evaluate the influence of control variables on the composting performance in a bin composting system. The model was verified using pilot scale composting system. Simulation of the composting temperature according to air flow rate and composting bin size was conducted using the mathematical model. High composting temperature above 55$^{\circ}C$ needed to kill a pathogen was maintained for longer periods as the air flow rate was lower and the bin size was larger. Optimum air flow rate was 0.77L/min/kg.DM for the experimental pilot scale bin system. The size of composting bin should be large enough to maintain the higher composting temperature for required periods.

• Phonetics and Speech Sciences
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• v.6 no.3
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• pp.149-153
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• 2014

In frequency domain ICA, the frequency bin permutation problem falls off the quality of separated signals. In this paper, we propose a new algorithm to solve the frequency bin permutation problem using the covariance of power ratio of separated signals in multi-channel FD-ICA. It makes use of the continuity of the spectrum of speech signals to check if frequency bin permutation occurs in the separated signal using the power ratio of adjacent frequency bins. Experimental results have shown that the proposed method could fix the frequency bin permutation problem in the multi-channel FD-ICA.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1719-1722
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• 2003

Image enhancement를 하기 위한 영상처리 알고리즘 중의 하나인 contrast enhancement 알고리즘은 화면의 flickering 과 같은 부작용과 조절 가능한 contrast enhancement rate 에 대한 구현의 어려움 등으로 실제 TV와 같은 동영상에 적용하기에 어려움이 있었다. 본 논문에서는 Bin Underflow Bin Overflow(BUBO)를 이용하여 동영상에 적용할 경우에도 flickering 등의 부작용이 생기지 않으며 contrast enhancement rate 을 조절할 수 있는 효율적인 알고리즘을 제안한다. 또한 이와 관련하여 영상의 휘도 레벨에 있어서 어두운 영역의 계조와 밝은 영역의 계조를 향상시킬 수 있는 black/white level stretch 알고리즘과 전체 화면의 출력 휘도 레벨에 대한 dynamic range를 유지하면서 brightness를 조절할 수 있는 알고리즘을 제안한다.

• International Journal of Computer Science & Network Security
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• v.21 no.3
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• pp.172-176
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• 2021

This study is conducted with an educational institution to minimize the potential security hazards to an acceptable level where the vulnerabilities and threats are revealed in this institution. The paper provides a general structure for the risk management process in educational institutions, and some recommendation that increases security levels is presented.

• Journal of Biosystems Engineering
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• v.30 no.3 s.110
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• pp.155-160
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• 2005

The objective of this research was to establish a domestically available cooling storage technique by cold-air in winter, using winter cool air ventilation fur determining rough rice cooling method in the storage and dry bin. The rough rice storage characteristics of two test conditions, winter cool-air ventilation storage and ambient temperature storage, were evaluated from January to July 2001, using a storage and dry bin of 300-ton capacity. Results of this research are as follows: Grain temperature was from $-5.1\~-8.5^{\circ}C$ after winter cool-air ventilation, and grain initial temperature for ambient temperature bin storage was $0.3\~1.9^{\circ}C$. Moisture content of rough rice decreased from $0.28\;to\;0.93\%$ and from $1.53\;to\;1.92\%$ to compare with original moisture contents for winter cool-air ventilation, and for ambient temperature bin storage, respectively. Broken ratio of brown rice from winter cool-air ventilation bin increased from $0.16\;to\; 0.92\%$, and brown rice broken ratio was from $2.24\;to\;2.86\%$ for ambient temperature bin storage to compare with initial broken ratio. Hardness of stored rice increased along storage period increase in alt storage methods, and cooling bin storage increased rice hardness of 0.271kgf: this increasing was lower then the other methods from 0.059 to 2.239kgf. Germination rates were decreased approximately 9.03, 3.14 and $3.20\%$ for upper, middle, and bottom of ventilating winter air bin, respectively, and germination rates of 2.70, 3.47 and $4.14\%$ were approximately decreased for upper, middle, and bottom parts of ambient temperature bin storage, respectively.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.11 s.188
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• pp.58-67
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• 2006

Due to the variety of signal processing and complicated mathematical analysis, it is not easy to accomplish 3D bin-picking with non-contact sensor. To solve this difficulties the reliable signal processing algorithm and a good sensing device has been recommended. In this research, 3D laser scanner and CCD camera is applied as a sensing device respectively. With these sensor we develop a two-step bin-picking method and reliable algorithm for the recognition of 3D bin object. In the proposed bin-picking, the problem is reduced to 2D intial recognition with CCD camera at first, and then 3D pose detection with a laser scanner. To get a good movement in the robot base frame, the hand eye calibration between robot's end effector and sensing device should be also carried out. In this paper, we examine auto-calibration technique in the sensor calibration step. A new thinning algorithm and constrained hough transform is also studied for the robustness in the real environment usage. From the experimental results, we could see the robust bin-picking operation under the non-aligned 3D hole object.