• Journal of the Korean Wood Science and Technology
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• 제42권3호
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• pp.258-265
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• 2014

목구조물 접합부에 기존 드리프트핀(Drift pin)을 대체하고자 단판이나 합판을 유리섬유강화플라스틱(GFRP: Glass fiber reinforced plastic)과 복합 적층시킨 GFRP보강적층목재핀을 제작하였다. 더불어 GFRP보강적층목재핀을 사용하여 집성재 접합부의 인장형 전단내력 시험을 실시하였다. GFRP 배열에 따른 보강적층목재핀의 휨강도 시험결과 GFRP를 각층에 1장씩 삽입한 시험편(Type-A)이 가장 양호한 성능을 발휘하였다. 또한 압체압력 $1.96N/mm^2$, 온도 $150^{\circ}C$에서 한 시간 열압하여 고밀화한 시험편이 고밀화하지 않은 시험편과 비교하여 휨강도 성능이 1.57배 향상됨을 확인하였으며, 하중방향에 따라 Edgewise가 Flatwise보다 3.51배 높은 성능을 발휘하였다. 시험을 통해 가장 양호한 성능을 보인 Type-A 보강적층목재핀을 이용하여 전단내력 시험을 실시하였다. 접합구의 종류와 접합판의 종류를 달리하여 시험한 결과 드리프트핀과 강판을 적용한 시험체(Type-DS)와 비교하여 GFRP보강적층목재핀과 GFRP보강목재적층판을 적용한 시험체(Type-WL)가 1.12배 높은 전단내력이 측정되었으며 최대하중 이후에도 매우 양호한 인성이 관찰되었다.

• 한국기계가공학회지
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• 제12권3호
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• pp.54-60
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• 2013

Numerical analysis of the radiant heat characteristic around heatsink according to arrangement and shape of fin on 60W-LED lamp is conducted in this study. In the case of top blow blowing from upper side on LED lamp, there is just little difference in cooling characteristics according to the height of fin. On the other hand, the fin arranged side by side has the advantage of heat transfer enhancement by comparing with zig-zag type because it leads to more loss of flow. In case of making fin round to increase the amount of heat transfer, designing arrangement with the minimized loss of flow has the advantage of characteristic.

• 도서관문화
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• 제45권5호통권348호
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• pp.24-29
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• 2004

학교 교사의 끝, 길고 좁은 골마루의 끝부분, 보일러실의 옆, 1층이라고 하지만 반 지하, 굳게 잠겨 있는 자물쇠, 출입문을 열면 학교도서관(교실 두 칸 정도 규모의 도서실이지만 학교도서관이라고 통칭하자.)은 모습을 드러낸다. 코를 자극하는 오랜 된 책 냄새, 잔뜩 쌓인 먼지, 여기저기 흩어져 있는 책, 훼손된 책, 여름 장맛비에 잠겼다가 말라서 부풀어 오른 책, 곰팡이 핀 책, 어떻게 분류해 놓은 것인지 도저히 알 수 없는 서가배열, 어디서부터 손을 대어야 좋은지 모를 곳, 이런 곳이 학교도서관의 주소였다. 그런 학교도서관을 새 단장하는 일이 대부분 비정규직 사서교사의 몫이다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.130-130
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• 2005

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2408-2413
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• 2007

Since the heat generation in a chip increases as the components are miniaturized and the computing speed becomes faster, suitable heat dissipation has become one of the primary limiting factors to ensure the reliable operation of the electronic devices. A pin-fin array could be used as an alterative cooling system of the electronic equipment. In this study, convective heat transfer through the pin-fin array is analyzed experimentally based on porous medium approach. The influence of the structure of the pin-fin array including the pin-fin spacing, the pin diameter and plate length on heat transfer characteristics is investigated and compared with the previous analytical results and existing correlation equations. Nowadays, electronic and mechanical devices become smaller and smaller. In this sense, the main purpose of this study is to decide the optimum pin-fin arrangement to get similar heat transfer performance when the length of the existing cooling system is reduced as a half.

• 융복합기술연구소 논문집
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• 제5권1호
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• pp.27-31
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• 2015

A Pin-fin array is widely used to enhance the heat transfer in the internal cooling passage. The heat transfer distribution around the pin-fin is varied by the horseshoe vortex and flow separation. The difference of heat transfer coefficient induces the large thermal stress, which is one of the major reasons to break of hot components. So, it is required to enhance the heat transfer on the back side of pin-fin to solve the thermal stress problem. This study suggests the pin-fin with inclined jet hole and complex pin-fin/dimple array to enhance the heat transfer on the back side of pin-fin. The heat transfer coefficient is predicted by the numerical analysis, which is performed by CFX 14.0. The numerical results are obtained at Reynolds number, 10,000. The results show that the heat transfer on the back side of pin-fin is increased in both cases. Beside, the wake, which comes from dimple and jet, helps to develop the horseshoe vortex and increase the heat transfer on the next row pin-fin.

• 설비공학논문집
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• 제18권6호
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• pp.459-467
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• 2006

Rapid development of electronic technology requires small size, high density packaging and high power in the electronic devices, which results in more heat generation. Suitable heat dissipation is required to ensure the guaranteed performance and reliable operation of the current state-of-the-art electronic equipment. The aim of the present study is to find out the forced-convective thermal-hydraulic characteristics of a pin-fin heat exchanger as a candidate for cooling system of the electronic devices through the analysis and experiment. Various configuration of the pin-fin array is selected in order to find out the effect of spacing and diameter of the pin-fin on the heat transfer and pressure drop characteristics. Experimental results are compared with the analyses and correlations of several researchers. Finally, the design guide are provided for the required pressure drop and/or the heat transfer characteristics of the heat exchanger.

• 한국전자파학회논문지
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• 제26권1호
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• pp.54-62
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• 2015

본 논문은 기생소자와 핀 다이오드 스위치를 이용한 전자식 전술 항법 장비(Tactical Air Navigation) 안테나에 대하여 설계 및 구현을 설명한다. 모터를 이용하여 기계적으로 안테나가 회전하는 대신 전자적으로 안테나를 회전시키기 위하여 기생소자를 원형 배열 형태로 배치하고, 핀 다이오드 스위치를 사용하였다. 방위정보를 포함하는 심장모양 패턴과 9개의 로브 패턴을 생성하기 위한 안테나의 구조적 특성과 설계 특징을 설명하고, 시뮬레이션을 수행하였다. 측정된 결과는 시뮬레이션과 일치하고, MIL-STD-291C 규격을 만족한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.1051-1054
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• 2005

On this study, we optimized minimizing the characteristic function for mixed result of the structural contact analysis and the buckling analysis according to the pin jig initial model's level change using mixed the table of orthogonal away and ANOM, Pin jig's weight is reduced up to 20 percent considering constraint conditions. Also we optimized reducing 20 percent weight of pin jig model using topology optimization.

• 설비공학논문집
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• 제19권5호
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• pp.418-425
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• 2007

The power consumption and heat generation in a chip increase as the components are miniaturized and the computing speed becomes faster. Therefore, suitable heat dissipation has become one of the primary limiting factors to ensure the guaranteed performance and reliable operation of the electronic devices. A pin-fin array which may be considered as a porous medium could be used as an alterative cooling system of the electronic equipment. The aim of the present study is to investigate the forced-convective heat transfer characteristics of pin-fin heat exchangers. Convective heat transfer through the pin~fin array is analyzed experimentally based on porous medium approach. The influence of the structure of the pin-fin array including the pin-fin spacing, the pin diameter and plate length on heat transfer characteristic is investigated and compared with the Previous analytical results and existing correlation equations. Nowadays, electronic and mechanical devices become smaller and smaller. In this sense, the main purpose of this study is to decide the optimum pin-fin arrangement to get similar heat transfer performance when the length of the existing cooling system is reduced as a half.