• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.405-412
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• 2000

A natural air in-bin grain dryer with a grain circulator was developed for on farm use. Natural air drying test for rough rice was carried out to evaluate drying rate, uniformity of moisture content distribution in grain bed and energy consumption. It took 10 days to dry 8 ton of paddy rice from 21.9%(w.b) to 16.7%(w.b) moisture contents using the prototype dryer. The average drying rate was 0.52%/day. The uniformity of moisture content after drying was superior to the conventional natural air dryer where is grains were not circulated during drying periods. The dryer performance evaluation index was 738.3KJ/(kg.water), which was more effective than that of grain circulation t)pe hot air dryer(3,500-5,000 KJ/kg.water).

• 생약학회지
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• 제1권4호
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• pp.115-118
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• 1970

Antihepatotoxic effect of dimethyl-esculetin, the major constituent of herbal drug Artemisia capillaris $T_{HUNBERG}$ (Compositae) which has long been used as folk medicine for gall stone and hepatitis in Asian country (China and Japan, except Korea) was investigated on the rabbit intoxicated with carbon-tetrachloride. Ten rabbits were divided into two parts, group A and B in five each. The group A was injected with carbon-tetrachloride, 0.1ml per kg at begining of the experiments for control. The group B was injected with carbon-tetrachloride soon after 7 days treatment of dimethyl-esculetin, 30mg per day. The results obtained in this experiment were as follows.: 1) Antihepatotoxic activity of dimethyl esuletin on the rabbits intoxicated with carbon tetrachloride has shown the serum glutamic oxaloacetic transaminase activity and serum glutamic pyruvic transaminase activity decreased respectively. 2) The component of Artemisia capillaris, dimethyl-esculetin, has shown remarkable antihepatotoxic effect.

• 한국기계연구소 소보
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• 통권13호
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• pp.3-13
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• 1984

Fatigue failure of axle housing could cause many injuries and much financial loss. This challenges the engineer to improve design decisions involving fatigue. Endurance evaluation of axle housing is great interest to auto-mobile manufacturers for the sake of safety and reliability. Axle housing is subjected to gross vehicle weight(G.V.W)as mean load and alternating load. Theoretical design diagram involving mean and alternating stresses is used for the evaluation of axle housing fatigue endurance with the equivalent stress of fatigue critical area on the axle housing. Four point bending fatigue tests on axle housing with constant amplitude loading at approximately R=0 were performed with 50 ton servohydraulic strucural fatigue testing machine developed at KIMM. Specimens were made with the same material STKM 13B as the axle housing and tested to obtain S_N data. Five specimens of STKM 13B were tested at 253.61 MPa and weibull distribution was obtained at the same stress level. Material data and structural data were compares and fatigue stress property factor and fatigue life property factor were obtained.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.85-87
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• 2001

Linear motor damper(LMD) for vibration control of structure is consisted of the NdFeB permanent magnets with high specific energy as the stator, a coil-wrapped nonmagnetic hollow rectangular structure and an iron core as a pathway for magnetic flux. The active mass of LMD is 1.5 ton and consisted of permanent magnet and iron yoke. In this paper, LMD system is manufactured and tested for dynamic characteristics and frequency response.

• 한국환경농학회지
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• 제17권2호
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• pp.164-169
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• 1998

토양반응이 산성이고 붕소함량이 낮은 사양질 밭에서 토양개량제로 석탄회와 석고, 패각을 석탄회 80, 패각4, 석탄회56+석고24, 석탄회40+석고24+패각0.8ton/ha 사용하고 가을 노지배추를 재배하여, 이들의 토양개량 및 작물증수 효과를 검토하였다. 전반적으로 석탄회, 석고, 패각 시용은 토양화학성을 개선시켰으며 배추 수량과 엽중 N, P, K, Ca, B 함량을 증대시켰다. 개량제중 석탄회를 단용한 구에서는 토양의 산도중화능이 우수하였고 유효인산 및 붕소의 증가와 철의 감소가 가장 뚜렷하였다. 석탄회+석고+패각의 혼용구에서는 칼슘, 마그네슘, 붕소의 증가가 뚜렷하였다. 그리고 석탄회가 시용된 구에서는 개량제 무시용구 및 패각단 용구와 달리 붕소결핍 없이 증수된 경향이었다. 처리별 증수효과는 대조구 수량 78.2ton/ha을 기준으로 석탄회+석고+패각 혼용구에서 85%, 석탄회+석고 혼용구에서 77%, 석탄회 단용구에서 66%, 패각 단용구에서 5%였다. 수확된 배추내에 N, B, 환원당, 비타민-C 함량은 처리별 성적 수량과 일치하였고 조섬유 함량은 그 반대 경향이었다.

• 한국해양환경ㆍ에너지학회지
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• 제10권3호
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• pp.148-154
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• 2007

본 연구에서는 낙동강 하구역 진우도 전면해역을 대상으로 해안쓰레기의 공간적 분포를 살펴보고 해양으로부터 유입되는 쓰레기의 종류를 분석한 뒤, 낙동강 하구역 사주의 해안쓰레기 분포량을 추정하고자 하였다. 이상의 결과를 요약하면 다음과 같다. 1) 낙동강 하구역 진우도 사주 전면해역을 대상으로 $50\;m{\times}50\;m(=0.0025\;km^2)$ 영역을 설정하고 영역내 모든 해안 쓰레기를 수거하여 해안쓰레기의 발생량을 평가하기 위한 모니터링 시스템을 구축하였다. 2) 초기 해안쓰레기 분포량을 살펴보기 위해 모니터링 영역내의 해안쓰레기를 수거한 결과, 총 1,110 kg의 해안쓰레기가 수거되었는데, 단위면적당($1\;km^2$) 발생하는 해안쓰레기량을 추정한 결과는 총 $444\;ton/km^2$이다. 1개월 경과후 조사시에는 총 23.75 kg의 해안쓰레기가 수거되었는데, 단위면적당($1\;km^2$) 발생하는 해안쓰레기량은 총 $9.5\;ton/km^2$ 이다. 1개월 변화기간동안의 퇴적량으로 환산하면 316.67kg/day/의 해안쓰레기가 퇴적되는 것으로 추정할 수 있다. 3) 모니터링 영역에 대해서 수거된 해안쓰레기중 가장 많은 양을 차지하는 것이 목재로서 85.86%, 폐그물 및 폐부이를 포함하는 어구가 5.13%, 플라스틱류가 4.78%, 생활쓰레기가 2.34%, 유리류가 0.94%, 음료수캔을 포함하는 철재류가 0.27%를 나타내었다.

• 농업과학연구
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• 제12권1호
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• pp.139-152
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• 1985

본 NEWASA 지역의 접수관정관개 개발에 따른 정제성분석 연구는 IBRD-EDI와 INDIA RESERVE BANK의 College of Banking이 공동주최한 Trainers Trining for Rural Finance (1985. 1.19-3.1)의 일환으로 1985. 2. 14-19 까지 NEWASA BLOCK에 대한 정수정관개의 경제적 효율성을 평가하기 위하여 농가조사를 실시하였고, 그 분석결과를 정리한 것으로 농지는 넓으나 농업용수가 부족한 본 지역은 빈곤과 저생산성 농촌잠재 실업을 특징으로 하고 있다. 농촌소득의 제고와 농촌실업의 고용확대는 전 인구의 80% 이상이 농민인 본지역뿐만 아니라 선언도 경제개발의 중심과제이다. 호당 6 acres 규모의 관개가 가능한 Dug-well Irrigation Development는 연평균 강우량이 650m/m에 불과한 인도의 Plateau 지역에서는 농촌빈곤과 실업문제의 해결, 토지 이용율제고를 통한 토지생산성 향상등 농촌경제개발의 중심과제로서 인도정부가 추진하는 핵심적인 농업정책이다. 본 지역의 농가호당 평균 소유농지연적은 8.67 acres(3.5ha)로써 모두가 Rainfed farming으로 현재 본 지역의 관개율은 17.5%에 불과하다. 농작물은 Jowar라고 하는 내한성 작물이 재배되며, 관개 조건하에서는 Jowar, Wheat, Sugarcane이 재배된다. With and Without Dug-Well Irrigation 조건하에서 각 작물별 ha당 생산성을 보면 Jowar는 0.86 ton/ha에서 2.22 ton/ha으로 증산되고 Wheat는 2.96 ton/ha, Sugarcane는 98.8 ton/ha이 생산된다. 한편 Dug-well Irrigation 전후의 농가소득의 변화를 보면 시행전의 4,275Rs가 되어 4배의 농가소득이 증가된다. 이와 같은 농업소득을 획득하기 위해서는 Dug-well에 대한 Initial Investment로서 33,400Rs(2,137,600원)이 투자되어야 하는데 종류별 융자 기간을 보면 Dug-well 15년(95%융자) Pump Set 9년(95%융자), Woriking capital 1년이며 인도의 Union Bank에서 융자하고 있다. 결론적으로 이러한 Dug-well Irrigation Development에 따른 IRR는 Before Financing시에는 29%이며 After Financing 시에는 24%이고 B/C ratio는 두경우에 있어 1.89, 1.24를 각각 나타냈다. 따라서, 본 사업은 재무적인 측면 즉 농가소득증대와 농촌고용증대 및 토지이용면에서 타당성이 크며 Dug-well Irrigation은 인도의 농업성장 및 경제개발의 관건으로 생각된다. 한국의 수리개발 기술 및 농업기술(Bio-chemical, Mechanical & Hydrological Technology)이 이전된다면 보다 괄목할 만한 농업발전이 이룩될 것을 생각된다.

• 대한기계학회논문집B
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• 제26권11호
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• pp.1578-1584
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• 2002

Combustion stability is one of the most important factors that must be considered in burning of heavy fuel oil, especially low-grade oil. This paper describes the combustion characteristics of petrochemical process by- product in the combustion furnace of heavy fuel oil. Main experimental parameters were combustion load, excess 02, fuel preheating temperature and air/fuel ratio. The capacity of CRF(combustion research facility) used in this study was 1.0 ton/hr and the burner is steam jet type suitable far heavy oil combustion and manufactured by UNIGAS in Italy. The fuel used in this experiment were 0.5 B-C, petrochemical process by-product and 3 kinds of 0.5 B-C/process by-product mixtures. The combustion stability was monitored and exhaust gases such as CO, NOx, SOx and particulates were measured with the excess $O_2$ and combustion load. The main purpose of this study is to clarify whether process by-product can be used as a boiler fuel or not in consideration of flame stability and emission properties.

• Journal of Biosystems Engineering
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• 제34권5호
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• pp.358-362
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• 2009

This study was conducted to evaluate the performance of a 12 tons capacity circulating concurrent flow rice dryer. An actual scale dryer with the capacity of 12 tons was developed to obtain a faster drying rate of 0.8~1.2%(w.b.)/h, while maintaining a lower drying energy consumption of 5,000 kJ/kg-water and achieving a drying quality that was comparable to a conventional cross-flow rice dryer. The Test-1 was conducted at $110^{\circ}C\;-\;20\;cmm/m^2$ and the Test-2 was conducted at $120-110-100-90^{\circ}C\;-\;20\;cmm/m^2$ under the same conditions as Test-1. In Test-1, the drying rate, drying energy consumption and crack ratio were 0.98 %(w.b.)/h, 4,573 kJ/kg-water and 3.2%, respectively. In Test-2, the drying rate, drying energy consumption and crack ratio were 0.74 %(w.b.)/h, 4,790 kJ/kg-water and 4.0%, respectively. The results of these tests demonstrated that this concurrent-flow dryer reached the desired drying rate, drying energy consumption and crack ratio.

• 연구논문집
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• 통권34호
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• pp.121-129
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• 2004

The influence of powder size and ball-milling time on the magnetic properties of $Fe_{73}Si_{16}B_7Nb_3Cu_1$ nanocrystalline alloy powder was investigated. Flake-shaped powders were produced by pulverizing the ribbons annealed at $550^\circC$ for 1 hour. The powders were classified and consolidated into core shapes at a pressure of 18ton/$cm^2$. The initial permeability at 100kHz of the inductor core produced using $53-75\mum$ powders showed the highest value although its consolidated density showed the lowest one. The reason for the result is due to the cracking of the particles larger than $75\mum$ during the consolidation process. The ball-milling of powders for 2-4 hours improved the consolidation density and the initial permeability of the cores. The intrinsic coercivity of the powder decreased as well, resulting from the stress relief of the powder by a short-time milling.