• 한국양식학회지
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• 제12권3호
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• pp.197-204
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• 1999

Successful produciton of seedlings for marine fish species are highly influenced by the aquisiton of sufficient number of good-quality eggs on required time. human chorionic gonadotropin has been used to induce successful ovulation for the purpose. Rabbitfish, siganus canaliculatus, is inhabited along the coast of Cheju Province and treated valuably for raw fish and fish roasted with seasoning. Female wild-captured rabbitfish (314 to 279 g in body weigth) were injected into intraperitoneal space with human chorionic gonadotropin (HCG) of 5,00,1,000, and 1,500 IU/kg body weight during spawning season of July 14 (trial 1), and July 27 (trial 2). Test fish in trial 1 were injected two times, first on July 14 and second on July 21 with one weekinterval because of no ovulation symptoms, but just one time in trial 2. All females injected both 1,000 and 1,500 IU/kg body weight ovulated in all trials. Among 500 IU/kg injection treatments, just one female ovulated in trial 1 showing 25% of ovulation rate, but none ovulated in trial 2. Ovulation was not occurred in control goups during test period. Time to reach ovulation after injection was 172 to 270 hours in trial 1 and 77 to 132 hours in trial 2, showing shorter as spawning season approached. Generally, ovulation of smaller females were late than that of larger ones. Gonadosomatic index (GSI) and pseudo-gonadosomatic index (Pseudo-GSI) were ranged 22 to 33% and 19 to 28%, respectively. One female spawned 406,200 to 1,032,000 eggs, and obtainable eggs per 100g of body weight were calculated by 130,000 to 190,000. Spawning rates were comparatively high by 96.0 to 98.4%. Rates to reach embryo-formation and hatching were higher in 500 high by 96.0 to 98.4%. Rates to reach embryo-formation and hatching were higher in 500 and 1,000 IU/kg treatments than in 1,500 IU/kg treatment. The result of present study demontrates that HCG treatment during spawning season could become very useful for ovulation of rabbitfish and the suitable dosage was suggested as 1,000 IU/kg of body weight.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1517-1522
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• 2011

Recently, application of LED luminaires has been issued for energy saving plan. In this paper, we carried out a study to replace a low efficacy sealed-beam lamp for headlight of railroad vehicles with LED luminaire. Electrical and optical characteristics of the sealed-beam lamp were analyzed and a LED headlight was designed and fabricated. Total luminous efficacy and rated power of the prototype LED headlight were 82 lm/W ; about 5 times higher, and 40W ; about 4 times lower than the sealed-beam lamp, respectively. Especially, lifetime of the sealed-beam lamp is short as 1,000 hours due to the evaporation and vibration of filament, but that of LED headlight is over 30,000 hours long.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.2050-2055
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• 2009

This paper describes the proceeding experimental results to replace the 32 [W] fluorescent lamp installed in subway train to a LED module. We fabricated 25 [W] LED modules to meet the illuminance 300 [lx] specified in the standard for subway train. After the installation of LED modules, comparative analysis with conventional fluorescent lamps was carried out. From the experimental results, illuminances on the height of 0.85 [m] and 1 [m] above floor were 323 [lx] and 360 [lx], respectively. These illuminances satisfied the requirement 300 [lx]. By the application of 25 [W] LED module as a light source in subway train, energy saving about 22 [%] compared with 32 [W] fluorescent is acquired. Also, low cost of maintenance is expected due to 8 times longer lifetime 50,000 hours of LED than that 6,000 hours of fluorescent lamp.

• 대한전기학회논문지
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• 제41권1호
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• pp.95-106
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• 1992

For commercial application of the MCFC, the life time of the MCFC should exceed 40,000 hours, But the life time of the state-of-the-art MCFC was limited to 15,000 hours. The main reasons of the life time limit can be classified as the deficiency of the electrolyte and cathode dissolution. It has been found that the electrolyte deficiency is caused by the continuous evaporation of the electrolyte. However a recent reaserch shows that an electrolyte pumping phenomenon, which implies, the migration of the electrolyte through the gasket material of the external gas manifold, is also the reason of the electrolyte deficiency. Due to the electrolyte pumping phenomenon, positive end cell of the stack suffers the electrolyte deficiency and negative end cell of stack is flooded with electrolyte. Therefore, the cell performance is degraded. The author invented a new manifoldcasing, which prevents the contact between the wet seal and the gasket of the manifold, and gives a complete elimination of an electrolyte pumping effect.

• 대한가정학회지
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• 제41권7호
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• pp.157-168
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• 2003

The purposes of this study were to explore the rural women's labor by measuring labor value economically. To achieve the purpose, this study applied four methods : replacement cost method individual function, replacement cost method generalist, opportunity cost method and shadow wage method. The results of this study were as follows: 1) Time used for agricultural work and household work by with women were 5.3 hours and 3.8 hours each. 2) According to the methods used, the amounts of valuing rural women's labor were varied and ranged from 23,000 won to 43,000 won per day. This study might help recognize the degree of rural women's labor contribution to the household income of farm households and improve the socio-economic status of rural women through showing the productivity of the rural women's labor.

• 분석과학
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• 제21권2호
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• pp.148-157
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• 2008

$1,000^{\circ}C$ 이상의 고온에서 수천~수만 rpm으로 작동하는 가스터빈 부품의 수명을 예측하기 위하여 크립파단 실험으로 얻어진 Larson-Miller 크립곡선을 활용하고 있다. 이 방법은 고온에서 시편에 하중을 주어 파단수명을 구하여 크립 파단수명을 온도와 하중의 함수로 나타낸 실험결과 곡선이다. 파손적 실험으로서 오차가 수십배를 상회하여 수명예측이 정확하지 않다. 반면에 본 연구에서는 비 파손적일 뿐 아니라 더 정확한 수명예측이 가능한 방법을 소개하고자 한다. 즉, $1,280^{\circ}C$에서 22,000시간(6,000 기동) 사용되어 폐기된 보령 가스터빈 제1단 단결정 블레이드(버켓)에 국부적으로 polishing한 후, 부식시킨 다음 replica를 떤다. 이 replica에 붙은 석출물들은 TEM과 SEM 사진으로 구하여 디지털 이미지하여 크기가 측정된다. 블레이드가 사용 전에 $0.45{\mu}m$ 크기에서 사용 후, $0.6{\mu}m$로 성장하였으나, 추가적으로 약 만여 시간 더 사용할 수 있으며 열처리를 추가하면 이만여 시간 더 사용할 수 있음을 알 수 있었다.

• KSBB Journal
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• 제16권2호
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• pp.163-169
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• 2001

This study was undertaken to evaluate the effects of green and taste teas on the in-vitro antimicrobial activity and vacuolating toxin titer of Helicobacter pylori. Crude aqueous extracts prepared by adding 2 g of tea leaf or powder to 100 ml of boiling distilled water, and sterilized by passing through a 0.22 $mutextrm{m}$ membrane filter. Green tea, coffee, and ginger tea showed bactericidal activity on H. pylori within 3 hours. Black tea and ssangwha tea also showed bactericidal activity on H. pylori in 24 hours. Arrowroot tea show no bactericidal effect on H. pylori after 48 hours. Two fold diluted green tea and coffee decreased(1/10,000cfu) the growth of H. pylori in 24 hours, but the two fold diluted black tea, ssangwha tea, and ginger tea showed suppression effect upon of(1/10cfu) H. pylori in 24 hours. The two-fold and 10-fold diluted green tea, coffee and two-fold diluted black tea abrogated the vacuolating toxin titer of H. pylori, but the two-fold and 10-fold diluted ginger, ssangwha, ginseng, and arrowroot tea only reduced the vacuolating toxin titer of H.pylori from 1/2 to 1/8. These result suggest that green tea and coffee have effective antibacterial or bactericidal effects on H.pylori, and that they also have a neutralization effect upon the vacuolating toxin of H.pylori.

• 한국미생물·생명공학회지
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• 제16권6호
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• pp.484-488
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• 1988

토양분리균 Pseudomonas sp.가 생산하는 inulinase를 분리.정제하여 얻은 단일 단백질 효소 PI과 PII는 탄수화물 함량이 각각 15%와 2.4%인 당 단백질 형태의 endo-inulinase로서 두 효소가 모두 촉매활성에 필수적인 tryptophan 잔기를 가지고 있었다. 분자량은 PI 210,000, PII 170,000으로 측정되었다. 1mM pCMB 존재에 의해 두 효소가 약80% 정도의 활성저해를 보였으나 5mM cysteine 또는 1mM dithiothreitol을 첨가하면 효소활성이 거의 완전 회복되는 특성을 나타내었다. 최종 가수분해산물인 fructose(1mM)에 의해 PI, PII 효소가 각각 15% 정도의 활성저해를 받는 반면 Co$^{+2}$ 이온은 50~60%의 높은 활성화 효과를 보였다. 두 효소는 pH 4.0~7.5사이에서 매우 안정하였으며, 열에 대하여서도 비교적 안정하여 6$0^{\circ}C$, 120분 가열에 의해 PI이 약 27%, PII가 약 40%의 실활을 나타낼 뿐이다. 또한 60units의 효소를 사용, 2% inulin을 5$0^{\circ}C$에서 72시간 가수분해 시켰을 때 PI약 70%, PII약56%의 기질 분해율을 보였다.

• 한국콘텐츠학회논문지
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• 제14권2호
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• pp.283-293
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• 2014

본 연구의 목적은 "8만 시간 디자인 공모전"에 제출된 에세이를 활용하여 베이비부머가 갖고 있는 노후에 대한 인식과 기대를 살펴보는 것이다. 2011년 첫 공모전에 참여한 인원 중에서 베이비부머 세대에 해당하는 62명분의 에세이 자료를 주제중심분석(thematic analysis)방법으로 분석하였다. 연구결과 첫째, 베이비부머 참여자들은 공모전을 통해 노후준비를 한다는 것의 의미를 재발견하고 있었다. 둘째, 이들이 계획하는 노후는 세 가지 모습으로 도출되었다: 1) 나 자신에게 집중된 삶, 2) 일과 관계, 여가가 조화롭게 연계된 삶, 3) 사회환원적인 창출을 꿈꾸는 공동체의 삶. 셋째, 참여자가 꼽은 필수 노후준비 사항은 건강관리와 배움의 기회를 적극적으로 활용하는 것이다. 그런데 베이비부머 참여자들은 노후준비에 있어서 성실하지만 약간 강박적인 모습을 보인다. 본 연구를 통해 베이비부머의 노후생활과 노후준비에 대한 구체적이며 현실적인 방안에 도움이 되는 지원 방향을 제공하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.824-829
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• 1998

In regard to the very stringent-going requirements applied to power supply systems is nowadays applications, the reliability of typical UPS redundency systems are investigated. Several resonable assumptions are made to build up the probability models. The reliabilities of the typical UPS redundency systems are analysed. Their relating Relaibility and MTTF (Mean Time To Faults) are evaluated. It is resulted in that the MTTF of today's UPS redundency systems is unlikely to be beyond 1,000,000 hours.