• 대한기계학회논문집B
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• 제30권12호
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• pp.1147-1154
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• 2006

An experimental investigation was conducted to enhance the heat/mass transfer for impingement/effusion cooling system when the initial crossflow was formed. For the improvement of heat transfer, the circular guide is installed on the injection hole. At the fixed jet Reynolds number of 10,000, the measurements were carried out for blowing ratios ranging from 0.5 to 1.5. The local heat/mass transfer coefficients on the effusion plate are measured using a naphthalene sublimation method. The result presents that the circular guide protects the injected jet from the initial crossflow, increasing the heat/mass transfer. The heat transfer of stagnation region is hardly changed regardless of the blowing ratio. The secondary peak is obviously formed by flow transition to turbulent flow. At high blowing ratio of 1.5, the circular guide produces $26{\sim}30%$ augmentation on the averaged heat/mass transfer while the case without circular guide leads to the low and non-uniform heat/mass transfer. With the increased heat/mass transfer, the installation of circular guide is accompanied by the increase of pressure loss in the channel. However, the pressure drop caused by the circular guide is lower than that for other cooling technique with the circular pin fin.

• 한국신뢰성학회지:신뢰성응용연구
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• 제17권2호
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• pp.143-149
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• 2017

Purpose: In recent years, weight reduction for improving fuel efficiency of the vehicle and cost reduction have been developed. The structure of suspension link is widely used as a single plate press structure which can reduce process and weight compared to existing pipe welding method. However, it was found that the lifetime of a single plate press structure is determined by initial defects that occurred during initial manufacturing rather than fatigue damage caused by driving. Methods: I research the mechanism of failure phenomenon of the single plate press assist arm of rear wheel. In addition, I investigate durability effect parameters to determine the link lifetime in inserting bush into single plate press process through durability test. Conclusion: I discover significant durability effect parameter in inserting bush into single plate press process. It is expected that the durability can be improved by suggesting a bush inserting process inspection guide for similar suspension link like single plate press structure.

• 한국기계가공학회지
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• 제19권4호
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• pp.30-35
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• 2020

The light guide plate (LGP) provides a surface light source on the back of the liquid crystal display (LCD), which is not self-emitting; thus, it is an essential component of display units requiring sufficient brightness. To maximize the light-emitting effect of an LGP, enough incident light, from the light source, should enter into its side. However, the current trend in LCD panels is represented by larger and thinner screens and this smaller thickness prevents the accordingly thin LGPs from providing sufficient brightness. This paper proposes a process for manufacturing wedge-type LGPs, which might increase the amount of incident light and, consequently the surface light emission, for applications in large LCDs. The proposed method was validated by building a dedicated manufacturing machine and performing illuminance experiments on the fabricated LGP.

• 플랜트 저널
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• 제9권3호
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• pp.48-52
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• 2013

본 연구에서는 전산유체해석(CFD)을 통하여 SCR 탈질설비 내부의 유동장 흐름을 전산모사하였다. 또한 유동장의 균일도를 분석하기 위해 기존 설비에 대한 해석을 수행하였으며 이를 통해 문제점을 도출하고 개선하였다. 개선방안으로는 곡관에 guide vane을 설치하여 곡관상에 기류를 균일하게 안내해 주었으며, baffle을 설치하여 SCR설비로 초기 유입된 기류의 균일한 공간 분포를 도출하였다. 마지막으로 porous plate를 baffle 하단에 설치하여 균일류 형성의 최적화 모델을 도출하였다.

• 한국해양공학회지
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• 제33권2호
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• pp.146-152
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• 2019

A design system was developed for the doubler plate of a ship structure simultaneously subjected to in-plane loads and lateral pressure based on general dimensions and those of a representative ship structure. An equivalent design equation that considers various structural design parameters was derived by introducing the equivalent plate thickness theory, and the design of the doubler plate reinforcement of the ship structure was developed. A hybrid structural design system was established for a doubler plate simultaneously subjected to in-plane loads and lateral pressure consisting of two modules: an optimized design module and a double plate strength & design review module. The practical application of this design system was illustrated to show its usability. It was found that the design safety of the doubler plate was ensured, and this system could be used as an initial design guide to review the double plate reinforcement for a dent or corrosion of the ship plate members. Using the developed design system would make it possible to obtain a more reasonable doubler plate structure that considers the rational reinforcement of plate members of ship structures. In addition, a more reliable structural analysis using a strength evaluation process can be performed to verify the efficiency of the optimum structural design for the doubler plate structure.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1062-1065
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• 2004

We have analyzed the cause of black "mura" and measured it in prism light guide plate(LGP). Properties of components used in a backlight uint(BLU) have changed by simulation tool. We get major factor of black "mura" for improvement in prism LGP. For the improvement of black "mura", removal of brightness "mura" at input light part must precede preferentially because of reflection characteristic of the prism LGP. Removal of brightness "mura" is improved by hanging of input light part in LGP and dispersion treatment.

• 대한기계학회논문집B
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• 제27권11호
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• pp.1604-1611
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• 2003

The experimental investigation of a coal splitter used in the 500㎿(e) boilers of fossil power plant is carried out to validate the design criteria. To predict air flow and the amount of particles at the exit, velocity and the weight of particles are measured on test planes using the coal splitter model with two-dimensional phase doppler particle analyzer and the glass fiber filter. It is found that the position of guide plate influences significantly both flow rates of gas and particle at the exit. Gas flow rate was a linear function of the guide plate, whereas particle flow rate was a exponential function of it.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.165-168
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• 2004

We have analyzed the cause of black "mura" and measured it in prism light-guide plate (LGP). Properties of components used in a back light. unit (BLU) have changed by Simulation Tool. We get major factor of black "mura" for improvement in prism LGP. For the improvement of black "mura", removal of brightness "mura" at input light part must precede preferentially because of reflection characteristics of the prism LGP. Removal of brightness "mura" is improved by changing of input light part in LGP and dispersion treatment.

• Transactions on Electrical and Electronic Materials
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• 제8권4호
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• pp.178-181
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• 2007

We have designed high performance prism light-guide plate (LGP) in 17 inch TFT-LCD. In test result to embody high brightness BLU in case of LGP of base and upper surface with 17 inch, thickness 8 mm adding prism construct, it is superior brightness improvement than previous that of printing form about some 20% and in this course to embody actual material it succeeded prism LGP production by 17 inch injection form process.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.51-54
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• 2005

Light Guide Plate (LGP) of LCD-BLU(Back Light Unit) is manufactured by forming optical pattern with $5\~100um$ in diameter on the LGP by means of sand blasting or etching method. However, in order to improve the luminance of LCD-LGP, the design of optical pattern has introduced UV inclined-exposure process in this study. This micro-optical pattern, which has asymmetric elliptical column shaped pattern, can change low viewing-angle to high viewing-angle, as well as it contribute to diffusion of light. As a result, this type of micro-optical pattern can introduce the highly luminance. The PR structure obtained in the stage of lithography has asymmetric elliptical column shape and it is processed into a micro-optical pattern. Optical design with this kind of micro-optical pattern, mold fabrication by electroplating and LGP molding with injection molding are under way.