• 제목/요약/키워드: earlier stage

검색결과 636건 처리시간 0.025초

초기 단계의 성능분포를 활용한 신뢰성 인증시험의 설계 (Design of Reliability Qualification Test Based on Performance Distribution at the Earlier Stage)

  • 정해성
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제12권3호
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    • pp.131-138
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    • 2012
  • A design of reliability qualification test based on performance distribution is developed. In general, the performance of an item degrades as the time goes by and the failure of an item occurs when the performance degradation reaches the pre-determined critical level. This article considers the reliability qualification test based on a more tightened critical value at the earlier stage to reduce the evaluation testing time and cost. A numerical example is provided to illustrate how to use the developed reliability qualification test.

버어리종 건조엽의 정유성분 I. 건조기간중 정유성분 조성의 변화 (Essential Oils in Cured Leaf of Burley Tobacco I. Changes in the Composition of Essential Oils during Air-Curing)

  • 배성국;김도연;김영회;조천준
    • 한국연초학회지
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    • 제22권2호
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    • pp.114-122
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    • 2000
  • This study was carried out to investigate the changes in the composition of essential oils for the improvement of air-curing process of burley tobacco leaves. From the essential oils isolated from the cured tobacco leaves by steam distillation method, 90 compounds including 15 acids and esters, 19 alcohols, 23 aldehydes and ketones, 19 hydrocarbons, and 14 miscellaneous compounds, could be identified by gas chromatography and gas chromatography-mass spectrometry. Among them, acids and esters were gradually decreased during the progress of curing after harvesting. A rapid increase in alcohol content was observed in the earlier stage of curing, but thereafter, decrease followed until the end of curing However, aldehyde and ketone groups were continuously increased during curing and were 3 times higher in quantity after curing than at the harvesting time. The concentration of hydrocarbons was increased in the earlier stage of curing, but gradually decreased from the middle stage. The miscellaneous compounds were continuously increased in content until the end stage of curing, with rapid increased in the earlier stage of curing.

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CGMMV 감염시기가 수박과 오이의 생육 및 품질에 미치는 영향 (Influence of CGMMV Infection Times on Growth and Quality of Watermelon and Cucumber)

  • 고숙주;이용환;이태선;양광열;박진우;최홍수
    • 식물병연구
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    • 제10권1호
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    • pp.48-52
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    • 2004
  • CGMMV의 감염시기가 수박과 오이의 생육 및 품질에 미치는 영향을 조사하였다. 수박은 생육달계별로 영양생장기 (정식기, 경엽신장기 )와 생식생장기 (착과기, 과실비대기)로 구분하여 CGMMV를 접종하였고, 오이는 정식기와 첫 개화기에 각각 접종하여 피해해석을 실시하였다. 수박의 경우, 영양생장기에 감염되면 만장, 절간장, 엽면적, 과중이 크게 감소하였으나 생식생장기부터는 대조구와 완만한 차이를 보였다. 반면에 당도는 착과기 이전에 접종하면 무처리에 비해 낮았으나 과실비대기에 접종하면 큰 차이 가 없었다. 피수박 발생은 감염시기가 빠를수록 증가하는 경향이었다. 오이의 경우 초장은 접종시기별로 큰 차이는 없었으나 만장은 접종시기가 빠를수록 감소하였고 절간장과 엽수, 엾폭, 엽장도 같은 경향이었다.

초고층 RC구조의 기둥축소량 해석 및 현장계측 (Calculation and Measurement of Column Shortening High-Rise RC Structure)

  • 이성원;박현일;김원식;오정근
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.133-138
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    • 2003
  • Axial shortenings of wall and columns were measured on level 2 and precise leveling between wall and columns were surveyed on level 5 at the Galleria Palace structure. Measured and surveyed shortening values were compared with the analysis results at the earlier stage on the process of construction for evaluating the predicted values. Though measured values represent relatively low and scattered values at earlier construction stage, probably they show similar slope curves to predicted ones with the progress of time.

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Competitive Performance of Hybrid Rice with Barnyardgrass

  • Lin, Wenxiong;Kim, Hak-Yoon;Shin, Dong-Hyun;Lee, In-Jung;Kim, Kil-Ung
    • 한국작물학회지
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    • 제44권4호
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    • pp.391-395
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    • 1999
  • Barnyardgrass had relatively higher growth vigor at the earlier growth stage than inbred rice did, showing the 2 fold higher $\alpha$-amylase activity during the periods of germination and large leaf area Expansion with high net photosynthetic rate at the earlier autotrophic stage, but it performed weak growth at the late growth stage. However, the hlybrid rice Shanyou 63 had significantly higher $\alpha$-amylase activity and net photosynthetic rate than that of barnyardgrass, exhibiting heterosis for two physiologica1 traits during the germination (6~12 days) and autotrophic phase, respectively. Accordingly, hybrid rice, Shanyou 63, exhibited heterotic effect at the early growing stage when were presented with barnyardgrass. Shanyou 63 exhibited stronger tillering ability, faster leaf area expansion and higher net photosynthetic rate than those of barnyardgrass.

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동태적 요인모형을 이용한 경기동행지수 개발에 관한 연구 (A Study of Business Cycle Index Using Dynamic Factor Model)

  • 나인강;손양훈
    • 자원ㆍ환경경제연구
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    • 제9권5호
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    • pp.903-924
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    • 2000
  • This paper examines the alternative method to measure the state of overall economic activity. The macroeconomic variables, used for business cycle, take more than a month after a period for collection and aggregation. The electricity generation data is compiled in mechanical ways just after the period. Based on this fact, we develop the two stage estimation method for coincident economic indicators in order to detect the business cycle in an earlier period, using Stock-Watson's Dynamic Factor Model. Using monthly data from 1970 to 1999, it is found that the experimental coincidence economic indicators are well-fitted to data and also that the estimates of two stage estimation method have good explanatory power, equivalent to the experimental coincidence economic indicators. While the RMSE of coincidence economic indicators is found to be 1.27%, that of the experimental coincidence economic indicators is found to be 1.31% and that of the two stage estimation method is around 1.44%. If we take consideration into the fact that it measures the business cycle in one month earlier, we come to the conclusion that the two stage estimation is of great use.

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수산물 시장의 유통단계별 가격전달의 비대칭성에 관한 실증 분석 (An Empirical Study on Asymmetric Price Transmissions in the Distribution Channels of Fisheries Market)

  • 이정미;김기수
    • 수산경영론집
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    • 제41권3호
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    • pp.59-78
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    • 2010
  • This paper tries to apply the asymmetrical price transmission(APT) behavior observed in the agricultural industry to supply chains of the domestic fishery industry by a statistical manner. The fore mentioned asymmetrical price transmission refers to when price movements in the later stage of the supply chain do not move in a normal or symmetrical manner corresponding to price movements in the earlier stage of the supply chain. Therefore, when the earlier stage price increase and the later stage price increases to a larger degree, it is called positive(+) asymmetry and the opposite behavior is called negative(-) asymmetry. The study examines the data from domestic producers of three fresh fish types, hairtail, mackerel, and cuttlefish, and tries to examine the price asymmetry between the producer or farm, wholesaler, and retail prices via an APT test utilizing unit root, cointegration, and error correction model. The study found, hairtail wholesale and retail pricing bas a negative asymmetric relationship while mackerel has a negative asymmetric pricing relationship at the producer and retail levels of the supply chain. In the case of cuttlefish, all levels of the supply chain showed negative asymmetrical behavior in the supply chain price transmission, meaning the earlier stage price changes are more rapidly and greatly inputted in the later stage of the supply chain pricing. We believe that the reason why the analysis results show negative price asymmetry is due to the uniqueness of fishery products having an important variable such as freshness. If price increases are greater and quicker than price decreases, then consumer demand, which is sensitive to price increases will decrease and subsequently result in the increase of inventory levels, reducing profits for retailers. Also, frozen hairtail, mackerel, and cuttlefish will act as substitute goods to fresh fishery products. Therefore, fresh fishery products have a high demand of price elasticity. When prices increase, demand quickly decreases. Therefore the profit of wholesalers and retailers to decrease, I think this is the main reason of APT in the supply chain of Korea' s fisheries industry.

연초(Nicotiana tabacum L.) 세대촉진에 관한 연구 I. 황색종 연초품종의 세대촉진 (STUDIES ON ACCELERATING GENERATION OF TOBACCO (MCOTIAWA TABACUM L.) UTILIZING THE PHYTOTRON)

  • 정윤화;정석훈;금완수;최상수;이승철
    • 한국연초학회지
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    • 제7권1호
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    • pp.25-31
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    • 1985
  • For shortening the tobacco breeding cycle, seedlings with 6, 8 and II leaves of 2 flue.cured tobacco varieties, day. neutral type and photoperiod-sensitive type, were grown in controlled-environment room (CER), programmed for temperature of $18^{\circ}C$ and 8.hour day period of 30 klux, for 20, 30 and 40 days. All of plants of day.neutral type variety treated in CER, regardless of seedling stage and duration, flowered earlier than the untreated plants. In the 6.leaf seedlings stage of photoperiod-sensitive type variety, plants treated for 20 and 30 days in CER did not accelerate the flowering. the tobacco plants, treated with low temperature for 20 days at 8.leaf seedling stage, flowered earlier in comparison with. the other treatment.

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자궁내막증 환자에서 혈청 CA 125치 동태에 관한 연구 (Serum CA 125 Levels in Patients with Endometriosis)

  • 이진용;윤병구;최영민;신창재;장윤석
    • Clinical and Experimental Reproductive Medicine
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    • 제17권2호
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    • pp.101-106
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    • 1990
  • Serum CA 125 was measured with immunoradiometric assay in fourty-one patients of endometriosis Serum CA 125 levels (Mean ${\pm}$ SEM, U/ml)in patients with endometriosis were 13.8${\pm}$3.3 in stage I , 17.3${\pm}$3.0 in stage II, 23.4${\pm}$4.9 in stage III, and 64.5${\pm}$13.2 in stage IV, which showed increment according to the stage of endometriosis. Serum levels in stage IV only were significantly elvated than those in control (15.3${\pm}$2.2), and those in advanced stage(III and IV ; 47.1${\pm}$9.5)were significantly higher than those in earlier stages (15.9${\pm}$2.2)and control. The assay revealed a sensitivity of 31.7% and the frequency of elevated levels (> 30.3 U/ml)in stage I, II, III and IV was 9. 1%, 18.8%,33.3%, and 87.5% respectively. Sensitivity in advanced stage was higher than that in earlier stage (64.3% vs. 14.8%). There data suggest that serum CA 125 assay might be a useful diagnostic tool in the advanced stage of endometriosis.

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