• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.10
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• pp.8-17
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• 2008

This paper presents a stable lighting method for HID lamp for ship from initial discharging current limit with discharging voltage control. The output voltage of the proposed control scheme is boosted for ignition, and the charging voltage is decreased by the resistor discharging. The proposed controller fires the initial discharge at the designed discharging voltage to limit the discharge current. After the discharging, constant current controller is used for brightness in steady state. The proposed control scheme can limit the initial discharge current using the starting point control without a complex voltage controller. so it can improve the life-time of HID lamp and get a stable discharge from restricted the initial discharge current. In order to improve the protection of the system, a simple instantaneous error detecting circuit for open state and short state of HID lamp is used. The proposed error detecting of HID lamp can protect the power system of lamp control. The effectiveness of the proposed controller is verified from the experiments of practical 2.5[kW] HID search light for ship.

• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.147-153
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• 2010

Sulgidduk samples containing 1, 2, and 4% Adenophora remotiflora powder and a control were examined for moisture content, gelatinization property, color, textural characteristics, and sensory qualities to determine the optimal ratio of Adenophora remotiflora powder in the formulation. The highest viscosity, lowest viscosity, final viscosity, setback and breakdown decreased as the contents of Adenophora remotiflora powder increased in the gelatinization property of flour blends of rice cake made with Adenophora remotiflora powder. The water content of rice cake with Adenophora remotiflora powder was 40.54~41.30% and there was no significant difference between samples with Adenophora remotiflora powder. L values indicating brightness were highest in the control group and all of the a values displayed green color indicating that they were negative. The b values were lowest in the control group and the values increased as the level of Adenophora remotiflora powder increased. Evaluation of the mechanical characteristics of rice cake with Adenophora remotiflora powder, hardness, cohesion, adhesion and chewiness were all higher in the control group and as its contents were rich, such properties were reduced. In addition, there was no significant difference between adhesion and chewiness. Adhesion and elasticity were low in the control group and as its contents were rich, such properties increased. The results of the sensory test revealed that the, control group containing 1% Adenophora remotiflora powder had the highest color, flavor, taste and overall preference.

• Journal of Power Electronics
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• v.15 no.2
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• pp.555-566
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• 2015

A TRIAC dimming LED driver that can control the brightness of LED arrays for a wide range of source voltage variations is proposed in this paper. Unlike conventional PWM LED drivers, the proposed LED driver adopts a TRIAC switch, which inherently guarantees zero current switching and has been proven to be quite reliable over its long lifetime. Unlike previous TRIAC type LED drivers, the proposed LED driver is composed of an LC input filter and a variable switched capacitance, which is modulated by the TRIAC turn-on timing. Thus, the LED power regulation and dimming control, which are done by a volume resistor in the same way as the conventional TRIAC dimmers, can be simultaneously performed by the TRIAC control circuit. Because the proposed LED driver has high efficiency and a long lifetime with a high power factor (PF) and low total harmonic distortion (THD) characteristics, it is quite adequate for industrial lighting applications such as streets, factories, parking garages, and emergency stairs. A simple step-down capacitive power supply circuit composed of passive components only is also proposed, which is quite useful for providing DC power from an AC source without a bulky and heavy transformer. A prototype 60 W LED driver was implemented by the proposed design procedure and verified by simulation and experimental results, where the efficiency, PF, and THD are 92%, 0.94, and 6.3%, respectively. The LED power variation is well mitigated to below ${\pm}2%$ for 190 V < $V_s$ < 250 V by using the proposed simple control circuit.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1748-1751
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• 1991

Generally, we can't acquire clear boundary or area from an image having obscure boundary like allergy image by using Sobel or Lapalace operator. Also, when the image not uniform in some part of a image in brightness, there are difficulties to use the global operator such as histogram, for the contour line doesn't have the same grey level. In this paper, we will propose an algorithm to improve those difficulties. The main idea of the algorithm is that we divide the image into many rectangular parts like a chess board, calculate the average of each part, and decide the local threshold for each pixel on the calculated value. In experiment, we can get the contour and area by this algorithm which is much like to the contour and area measured by a doctor. Also, This algorithm has many advantages such as short processing time and little influences of noises and can be used in the robot vision, etc..

• Korean journal of food and cookery science
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• v.26 no.5
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• pp.552-558
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• 2010

This study was performed to provide basic data on the use of green laver for jook. To accomplish this, we tested water content, color, brightness, mechanical qualities and sensory qualities in comparison to a control group. Higher concentration of green laver powder decreased water content, lightness, redness, viscosity and pH. Further, higher concentration of green laver resulted in lowered preference regarding appearance. However, better flavor was with the result of a higher amount of green laver. Therefore, green laver seems to have benefits for use in oriental soup. Accordingly, we expect there is potential for use of green laver for jook.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2004.04a
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• pp.56-65
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• 2004

The Asia Pacific papermaking giants are China, Japan and Korea followed by Indonesia. The strong trends in recent years have been the move to alkaline/neutral sizing which has assisted the move from kaolin and talc as the major filler minerals to ground calcium carbonate and precipitated calcium carbonate. Kaolin remains important as a constituent in many coating formulations and Chinese-sourced talc, due to its brightness and price will remain important especially in paper filler minerals. The need for ever increasing printing surface quality and continuing efforts by the paper manufacturers to keep costs under control will ensure minerals in papermaking will continue to be a dynamic subject in the years ahead.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.2
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• pp.68-73
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• 2001

This experiment was executed to clarify the optimum condition of reductive bleaching for 100% color papers. The reductive bleaching of the color paper was desirable to be done under such conditions as high temperature over $60^{\circ}C$ and high consistency within possibly short time. The FAS bleaching like the sodium hydrosulfite required oxygen-free condition. Especially, as the mixture between pulps and chemicals was favored in case of the high consistency, it was actively recommended. Therefore, it is desirable to control the dosage with the type of the dyes, the nature, the dye content, the paper compositions, and the targeting initial and final brightness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.5
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• pp.55-59
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• 2011

Atmospheric plasma technology was utilized in order to modify surface characteristics of base paper for coating. Argon(Ar) and oxygen(O2) gases were used. It was found that contact angle of a water droplet was decreased with increasing voltage during plasma treatment, meaning that the hydrophilicity of paper surface was increased. On the other hand, the physical properties like roughness and optical properties such as gloss, brightness and opacity were not influenced by the plasma treatment. In conclusion, atmospheric plasma technology can be utilized to control hydrophilicity of paper surface without affecting physical properties of the paper.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.418-420
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• 2017

전광판을 통해 이미지를 표시할 때 이미지를 구성하는 각 화소에 대응하는 도트들 별로, 모두 일정한 밝기로 색상을 출력하기 때문에 이미지 내에 다양한 색상이 포함되어 있는 경우, 상대적으로 밝은 색상이 어두운 색상보다 더 밝게 보이는 문제를 가지고 있다. 또한 기존의 전광판들은 전광판을 통해 글자를 표시할 때 글자의 크기에 관계없이 모두 일정한 밝기로 글자를 표시하기 때문에 상대적으로 작은 글자가 큰 글자에 비해 잘 보이지 않는 문제가 있다. 우리는 전광판을 통해 이미지를 표시할 때, 해당 이미지 내의 다양한 색상들에 따라 부분적으로 전광판의 각 도트들의 휘도를 서로 다르게 출력하고, 전광판을 통해 글자를 표시할 때, 글자의 크기 별로 휘도를 서로 다르게 출력함으로써, 전광판을 통해 표시되는 정보에 대한 가독성을 향상시킬 수 있는 RICS 시스템을 설계한다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.31-34
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• 2001

Changing to a 24-hour urbanistic life style, a night time activities constituted for a major portion. Important of a beautiful exterior lighting as well as safety, and security concerns become increasingly. However, the removal or control of the excessive lighting is considered more important then increasing the brightness of the lamps to achieve bother safety and security. Representing a cheerful and leisure environment from the exterior lighting can also harmonize two aspects of energy saving and sustaining green environment. Designing of exterior lighting at the ＯＯ Agricultural & Fishery Circulation center symbolizes the suitability, convenience and production. It's design and analysis represent the optimum urban night time environment.