H₂O/LiBr+HO(CH₂)₃OH계 공냉형 이중효용 흡수식 냉방시스템의 사이클 해석

권오경,문춘근,윤정인,Kwon, Oh-Kyung,Moon, Choon-Geun,Yoon, Jung-In 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.2

A cycle analysis was achieved to predict the characteristics by comprehensive modeling and simulation of an air-cooled, double-effect absorption system using a new $H_2O/LiBr+HO(CH_2)_3OH$ solution. The simulation results showed that the new working fluid may provide the crystallization limit 8% higher than the conventional $H_2O/LiBr$ solution. With a crystallization margin of 3wt%(weight%), the optimal solution distribution ratio was found in the range of 36 to 40%. Variation of cooling air Inlet temperature has a sensitive effect on the cooling COP and corrosion problem. The simulation of heat exchangers with UA value revealed that the absorber and the evaporator are relatively important for an air-cooled system compared with the condenser and the low temperature generator. The effect of cooling air flow rate, circulation weak solution flow rate and chilled water inlet temperature were also examined. The new working fluid may provide the COP approximately 5% higher than the conventional $H_2O/LiBr$ solution.

수직관 흡수기의 물질전달에 미치는 계면활성제의 영향

권오경,윤정인,윤재호,Kwon, Oh-Kyung,Yoon, Jung-In,Yun, Jae-Ho 대한기계학회 2003 大韓機械學會論文集B Vol.27 No.5

This study was concerned with the enhancement of mass transfer by surfactant added to the aqueous solution of LiBr. Different vertical inner tubes were tested with and without an additive of normal octyl alcohol. The test tubes were a bare tube, groove tube, corrugate tube and inserted spring tubes. The additive concentration of normal octyl alcohol as a surfactant is about 0.08mass%. The Sherwood number was measured as a function of film Reynolds number 20~200. The experimental results were compared with those which use no surfactant. The enhancement of mass transfer by Marangoni convection effect which was generated by addition of the surfactant is proved for each testing tube Especially, it is clarified that the tube with the spring has the highest enhancement effect. A correlation of the experimental mass transfer data for the bare, groove, corrugate and insert spring tubes results expressed as the form of Sh=cㆍ Re$_{f}$ $^{n}$ .

반복세탁 및 전단·인정변형에 따른 텐셀직물의 피로도

권오경,이창미,김묘향,박희웅,Kwon, Oh-Kyung,Yi, Chang-Mi,Kim, Myo-Hyang,Park, Hee-Ung 한국의류산업학회 1999 한국의류산업학회지 Vol.1 No.3

This study was conducted to examine the fatigue phenomenon of mechanical properties in tencel fabrics by repeated washing & shear and tensile deformation. The obtained results are as follows. After performing repeated shear tensile deformation, RT of tencel showed higher increase rate than that of cotton and rayon, whereas its WT and EM was a smaller decrease rate than that of them. This means that tencel's resistance to tensile deformation was the greatest. In the repeated washing and shear tensile deformation, tencel's 2HB, 2HG and 2HG5 showed a remarkable increase rate. In terms of deformation frequency, the greatest change rate appeared at the time of 1000 cycles of repeated shear tensile deformation and 15 times of repeated washing. In the hand value and THV, KOSHI showed a higher increase rate for tencel than for cotton and rayon in both repeated washing and shear tensile deformation, and NUMERI showed a higher increase rate. In the THV the change rate of rayon and cotton could be rarely seen but for tencel, it decreased. tencel's change rate of thermal insulation value by materials was 1.08%, and it increased as the washing frequency increased, compared to the grey fabrics, whereas the change rates of cotton and rayon were 0.74% and 0.22%, respectively. The qmax decreased in the order of cotton>tencel>rayon as the washing frequency increased.

샘물의 구조성 발색과 바이오미메틱스 섬유

권오경,고재운,최영희,이상아,Kwon, Oh-Kyung,Kouh, Jae-Oon,Choi, Young-Hee,Lee, Sang-A 한국의류산업학회 2006 한국의류산업학회지 Vol.8 No.2

마직물 및 마혼방직물의 온열특성에 대한 흡습의 영향

권오경,이참미,성우경,Kwon, Oh-Kyung,Yi, Chang-Mi,Sung, Woo-Kyung 한국의류산업학회 1999 한국의류산업학회지 Vol.1 No.2

The thermal properies of the pure linen fabrics available in the market and linen blended woven fabrics were measured at the moisture content of 0%, 20%, 40% and 60% using KES-F7 system (Thermo Iabo II type). The experimental properties were statistically analyzed by the rate of water absorbent. The main results were as follows; There is a positive correlation between the thermal insulation value (TIV) and thickness of pure linen fabrics and linen blended woven fabrics by water absorption. Whereas an negative correlation exists between the TIV and cover factor. There is a high positive correlation among the thermal conductivity (k), thickness and weight of pure linen fabrics and linen blended woven fabrics by water absorption. Wherase a high negative correlation exist between the k and air' permeability (Ap). There is a high positive correlation between the feeling of warmth/coldness and bulk density of pure linen and linen blended woven fabrics by water absorption. Wherase a high negative correlation exists between the feeling of warmth/coldness and porosity. There is a negative correlation between TIV and $q_{max}$ of pure linen fabrics and linen blended woven fabrics. The higher the rate of water absorbent, the lower the TIV. This means that TIV decreases by water absorption. As for the thermal property by rate of water absorbent $q_{max}$ and k increase by water absorption and reach max-value at 60% rate of water absorbent. The TIV decreases by water absorption and has +value at 0% rate of water absorbent, whereas it has -value with a feeling of coldness at 20%, 40%. and 60% rate of water absorbent.

지역난방용 2단 압축 히트펌프에 관한 연구

권오경(Oh Kyung Kwon),차동안(Dong An Cha),박차식(Cha Sik Park),이학수(Hak Soo Lee) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.5

본 연구의 목적은 지역난방 적용을 위해서 25℃ 정도의 폐열을 증발기의 열원수로 활용한 2단 압축 히트펌프의 성능 특성을 실험적으로 조사하였다. 2단 압축 히트펌프는 10RT급으로 설계ㆍ제작하여 실험을 수행하였다. 2단 압축 히트펌프의 난방능력과 COP는 열원수 온도가 증가함에 따라 증가하였지만 과열도가 증가함에 따라서는 다소 감소하는 경향을 보였다. 2단 압축 히트펌프에서 중간압력은 열원수의 온도, 온수유량, 과열도에 따라서 달라짐을 확인하였다. 고온수는 1단/2단 압축기 회전수, 온수유량, 과열도의 조절을 통해서 70℃이상이 생산가능 하였다. The objective of this study is to investigate the main parameters that affect performance of a two-stage compression heat pump using waste water as a heat source for district heating application. To achieve the objectives of this study, the experimental evaluations of the 10RT class two-stage heat pump were carried out. The healing capacity and COP of the 2-stage heat pump increased with increasing heat source temperature, but decreased with increasing degree of superheat. Additionally, each intermediate pressure was able to find by varying heat source temperatures, hot water flow rate and degree of superheat. The hot water over 70℃ was produced by adjusting 1-stage/2-stage compressor speed, hot water flow rale and degree of superheat.

농약사용 지표개발을 위한 과수용 농약사용량 조사분석

권오경(Oh-Kyung Kwon),홍수명(Su-Myeong Hong),최달순(Dal-soon Choi),박찬원(Chan-Won Park),송병훈(Byeong-Hun Song),류갑희(Gap-Hee Ryu),오병렬(Byung-Youl Oh) 한국농약과학회 2001 농약과학회지 Vol.5 No.4

농약사용과 관련하여 환경영향 감소를 위한 농약사용 지표 개발에 활용하고자 사과, 배 등 6종 과수를 대상으로 재배면적별 22지역 70농가를 선정하여 국내 과수재배 환경 중 농약의 사용량을 조사 분석하였다. 과수재배시 용도별 농약 사용경향은 살균제>살충제>제초제 순이었으며 사과의 경우 전체 사용량 증 살균제가 72%로서 해충방제가 우선인 벼재배와는 달리 병해방제 위주의 농약사용을 나타냈다. 살균재 중 주요 사용농약은 Mancozeb, Propineb, Thiophanate-methyl이었으며 살충제의 경우 Propagite, Omethoate가 우선적으로 시용되었다. 제형별 농약사용량은 수화재 농약 위주의 사용경향을 나타냈으며 WP>EC>SL>SC>SP>WG 순이었다. 과수별 단위면적당(a.i./㏊)농약사용량은 감률 48.6 ㎏, 사과 27.1 ㎏, 배 18.6 ㎏, 감 17.5 ㎏, 복숭아 11.3 ㎏, 포도 9.2 ㎏으로서, 이를 미국의 농약사용량과 비교한 결과 사과는 한국의 사용량이 더 많은 살포약량 경향을 나타냈으나 감귤, 배, 복숭아의 경우 미국의 농약사용량이 더 많았다. 농약 사용량의 조사분석은 농약위해성 경감을 위한 단위면적당 농약 사용량을 감소 시키는 것이 그 목적이므로, 향후 전반적인 농업환경을 반영시킨 전체 작물별 농약 사용량 조사와 함께 작물별 농약 사용량을 경감시킬 수 있는 요인분석이 요망된다. Pesticide actual usage in fruit crop cultivation was surveyed, and usage trends of individual pesticides were evaluated to provide data for the development of indicators of environmental impact. The amount of pesticide used for fruit crops indicated the order of fungicide> insecticide> herbicide unlike the case of paddy rice, The fungicide rate of total usage was 72% in apple cultivation. Top ranking fungicides used on fruits were Mancozeb, Propineb, Thiophanate-methyl and the main insecticides were Propargite, Omethoate, Methidathion. The usuage by formulation types showed the order of WP>EC>SL>SC>SP>WG. Pesticide usage (a.i.) per hectare by different fruits was citrus 48.6㎏, apple 27.1㎏, pear 18.6㎏, persimmon 17.5㎏, peach 11.3㎏ and grape 9.2㎏. Comparison of pesticide usage (a.i.,㎏/㏊) in some fruit crops between Korea and USA indicated that more pesticides were used for citrus, pear and peach in USA than Korea while more pesticides were used in Korea than USA for apple.

흡수식 냉온수기용 증발기의 전열성능에 관한 연구

권오경(Oh-kyung Kwon),차동안(Dong-an Cha),윤재호(Jae-ho Yun),김효상(Hyo-sang Kim) 대한설비공학회 2008 대한설비공학회 학술발표대회논문집 Vol.2008 No.2

The objectives of this paper are to measure the heat transfer and pressure drop of the heat transfer tube for an evaporator of absorption system applications. Five types of heat transfer tubes with different shape and heat transfer area are tested in the present experiment. Heat transfer and pressure drop performance of heat transfer tubes are measured in various operating conditions, and compared each other. The results show that the heat transfer rate of thermoexcel notch tube and low fin tube increases about 27.6% and 11.6% at the refrigerant flow rate 250 ㎏/h compared with that of bare tube, respectively. The thermoexcel notch tube is shown the best performance considering pressure drop and heat transfer coefficient.

해운대 풍경의 시적 관념화 고찰

권오경(Kwon, Oh-Kyung) 동남어문학회 2010 동남어문논집 Vol.1 No.30

'스콜라' 이용 시 소속기관이 구독 중이 아닌 경우, 오후 4시부터 익일 오전 7시까지 원문보기가 가능합니다.

The purpose of this paper is to research what were poetries have been felt and expressed about scenic of Haewoondae from the late of Korea dynasty to the Modern time. To study the poetic idealization from the scenic of Haewoondae, 146 texts of Chinese style poems and 50 texts of modern poems were used in this paper in the point of stuff tradition. The results are as follows; Haewoondae landscapes were generalized as a land of where Taoist hermit live. So many people have wanted to visit the Haewoondae, 'dae' is a korean style small breaking building- which was built by great scholar Chi-Woon, Choi who lived in the late of Silly dynasty and disappeared into the mountain as being Taoist hermit. Because of this legends, many people have written poems and remembered him for a long time. The main materials for writing a poem were Chi-Woon, Choi, and the Dongbaek(Camellia flower) island, and cloud, moon, sea water, wave,O-ryuk-do island, stone carving of Haewoondae letters. Especially nobles in the middle age wanted to meet him and talk over a bottle of wine with him. But it's just dream. The Haewoondae imagine was made as the world of taoism by using taoist materials. For a long time many poetries written poems to subject themselves by describe him as a taoist man or to realize a taoist world, or to enjoy the ideal world. In the case of modern poems, so many matters are used to express the scenic of Haewoondae. The themes are classified as two types, the one is about the traditional imagine like Chi-Woon, Choi and the taoist, and the other is about modern imagine like love, and the missing lover, the imagine mother, healthy sensualism, a feeling of vitality. In the late case, because poems are living and feel the Haewoondae ocean and landscapes lively, the poetries are also modernized and personally.(Pusan University of Foreign Studies)

Ricinine의 합성법 및 살충활성

권오경(Oh-Kyung Kwon),임수길(Soo-Kil Lim),최달순(Dal-Soon Choi),경석헌(Suk-Hun Kyung) 한국농약과학회 1998 농약과학회지 Vol.2 No.1