• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.15-15
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• 2009

In many applications for display with LED, the thermal behavior of LED is most important issue in view of thermal management. The optical requirements of the displays for various applications make the designer to drive the LED at or over their on-design condition to achieve performances requested by users. In practical cases of large-sized TV with LED back light unit (BLU), the problem of increasing LED temperature can affect the reliability of LED itself and the optical performances of BLU as an assembly of LED. In this paper, the thermal management design of LED back light unit(BLU) for large-sized TV was performed

• 한국분무공학회지
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• 제13권4호
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• pp.193-199
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• 2008

Spray coating is a versatile surface modification technology in which coating is built-up based on the successive deposition of micron-scaled particles. Depending on the coating materials, the coatings can meet the required mechanical properties, corrosion resistance, and other properties of base materials. Spraying processes are mainly classified into thermal and kinetic spraying according to their bonding mechanism and deposition characteristics. Specifically, thermal spraying process can be further classified into many categories based on the design and mechanism of the process, such as frame spraying, arc spraying, atmospheric plasma spraying (APS), and high velocity oxygen-fuel (HVOF) spraying, etc. Kinetic spraying or cold gas dynamic spraying is a newly emerging coating technique which is low-temperature and high-pressure coating process. In this paper, overall view of thermal and kinetic spray coating technologies is discussed in terms of fundamentals and industrial applications. The technological characteristics and bonding mechanism of each process are introduced. Deposition behavior and properties of technologically remarkable materials are reviewed. Furthermore, industrial applications of spray coating technology and its potentials are prospected.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 전력전자학술대회
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• pp.435-436
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• 2017

This papaer is study on thermal analysis of the active-front-end(AFE) rectifier for solid-state-transformer(SST) applications. finite element analysis simulation model is combined by switching component model, power diode and heat-sink model. thermal model is calculated by computer program and feedback the result. using simulation result analysis switching loss and compare to thermal diffusion of the heat in the model for steady-state operation.

• 한국기계가공학회지
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• 제17권5호
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• pp.111-116
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• 2018

Thermal fusion bonding is a method to enclose open microchannels fabricated on polymer chips for use in lab-on-a-chip (LOC) devices. Polymethyl methacrylate (PMMA) is utilized in various biomedical-microelectromechanical systems (bio-MEMS) applications, such as medical diagnostic kits, biosensors, and drug delivery systems. These applications utilize PMMAs biochemical compatibility, optical transparency, and mold characteristics. In this paper, we elucidate both the conformational entanglement of PMMA molecules at the contact interfacial regime, and the qualitative nature of the thermal fusion bonding phenomena through systematic molecular dynamics simulations.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.67-68
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• 2023

This paper reports on the synthesis of paraffin-based phase change materials (PCMs) designed for use in solar reflective paint (SRP) as a thermal energy storage (TES) medium. These PCMs are prepared using the sol-gel process and are encapsulated in silica. The focus of this research is to evaluate the suitability of these synthesized PCMs for efficient thermal energy storage within SRP applications. The obtained PCMs have nanometric dimensions, which make them well-suited for integration into paint formulations. The study also includes a thorough analysis of the chemical, thermal, and structural stabilities of these materials, confirming their applicability in solar reflective paint.

• 한국재료학회지
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• 제10권5호
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• pp.354-659
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• 2000

자동차, 항공기 및 기타 산업에서 복합재료의 사용은 증가되어 왔고 활발한 연구가 진행되고 있다. 이러한 복합재료중의 하나인 carbon-epoxy 복합재료의 열 특성에 관하여 알아보았다. 반복적인 냉각과 가열이 부가된 후 복합재료의 탄성계수의 변화를 관찰하여 봄으로써 복합재료가 가지고 있는 여러 열 특성에 관하여 여러 열 특성에 관하여 연구하였다. 이 연구에서는 G(sub)13값은 약한 감소하기는 하였으나 별다른 변화를 보이지 않았으며 열충격의 경우가 열피로의 경우보다 변화량이 작았다. $E_1$값은 가해진 온도와 가열 횟수에 따라하여 조금씩 증가하였고,$ E_2$, G(sub)23값은 열피로의 경우 처음에는 어느 정도 그 값이 감소하나 가해진 횟수에는 큰 영향을 받지 않았으며 열충격의 경우에는 온도에 따라 다른 현상을 보였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.78-78
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• 2012

In this presentation I will review the expanding thermal plasma chemical vapour deposition (ETP-CVD) technology, a deposition technology capable of reaching ultrahigh deposition rates. High rate deposition of a-Si:H, ${\mu}c$-Si:H, a-SiNx:H and silicon nanocrystals will be discussed and their various applications, mainly for photovoltaic applications demonstrated. An important aspect over the years has been the fundamental investigation of the growth mechanism of these films. The various in situ (plasma) and thin film diagnostics, such as Langmuir probes, retarding field analyzer, (appearance potential) mass spectrometry and cavity ring absorption spectroscopy, spectroscopic ellipsometry to name a few, which were successfully applied to measure radical and ion density, their temperature and kinetic energy and their reactivity with the growth surface. The insights gained in the growth mechanism provided routes to novel applications of the ETP-CVD technology, such as the ultrahigh high growth rate of silicon nanorystals and surface passivation of c-Si surfaces.

• The Korean Journal of Ceramics
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• 제2권4호
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• pp.177-180
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• 1996

Considerable progress in the development of CVD techniques for the deposition of diamond films has been achieved recently. Despite the polycrystalline structure of this material, its physical properties are now approaching those of natural type IIa diamond crystals. This paper will given some insight into the current status of CVD diamond thechnology with emphasis on optical and thermal applications. The role of process gas impurities like nitrogen will be discussed.

• 한국압력기기공학회 논문집
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• 제14권1호
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• pp.8-14
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• 2018

Printed circuit heat exchangers (PCHEs) are widely used with an increasing demand for industrial applications. PCHEs are capable of operating at high temperatures and pressure. We consider a PCHE as a candidate intermediate heat exchanger type for a high temperature gas-cooled reactor (HTGR). For conventional application using stainless steels, design and manufacturing of PCHEs are well established. For applications to HTGR, knowledge of longitudinal conduction and deformation of channel is required to estimate design margin. This paper analyzes the effects of longitudinal conduction and deformation of channel on thermal performance using a code internally developed for design and analysis of PCHEs. The code has a capability of two dimensional simulations. Longitudinal conduction is estimated using the code. In HTGR operating condition, about ten percent of design margin is required to compensate thermal performance. The cross-sectional images of PCHE channels are obtained using an optical microscope. The images are processed with computer image process technique. We quantify the deformation of channel with dimensional parameters. It is found that the deformation has negative effect on structural integrity. The deformation enhances thermal performance when the shape of channel is straight in laminar flow regime. It reduces thermal performance in cases of a zigzag channel and turbulent flow regime.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.494-494
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• 2013

Atmospheric pressure non-thermal plasma of the needle-typed interaction with aqueous solutions has received increasing attention for their biomedical applications [1]. In this context, surface discharges at bio-solutions were investigated experimentally. We have generated the non-thermal plasma jet bombarding the bio-solution surface by using an Ar gas flow and investigated the emission lines by OES (optical emission spectroscopy) [2]. Moreover, The non-thermal plasma interaction with bio-solutions has received increasing attention for their biomedical applications. So we researched, the OH radical density of various biological solutions in the surface by non-thermal plasma were investigated by Ar gases. The OH radical density of DI water; deionized water, DMEM Dulbecco's modified eagle medium, and PBS; 1x phosphate buffered saline by non-thermal plasma jet. It is noted that the OH radical density of DI water and DMEM are measured to be about $4.33{\times}1016cm-3$ and $2.18{\times}1016cm-3$, respectively, under Ar gas flow 250 sccm (standard cubic centimeter per minute) in this experiment. The OH radical density of buffer solution such as PBS has also been investigated and measured to be value of about $2.18{\times}1016cm-3$ by the ultraviolet optical absorption spectroscopy.