• International Journal of Reliability and Applications
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• 제18권2호
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• pp.83-98
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• 2017

Stress-strength reliability problems arise frequently in applied statistics and related fields. In the context of reliability, the stress-strength model describes the life of a component, which has a random strength X and is subjected to random stress Y. The component fails at the instant that the stress applied to it exceeds the strength and the component will function satisfactorily whenever X > Y. The problem of estimation the reliability parameter in a stress-strength model R = P[Y < X], when X and Y are two independent two-parameter Lindley random variables is considered in this paper. The maximum likelihood estimator (MLE) and Bayes estimator of R are obtained. Also, different confidence intervals of R are obtained. Simulation study is performed to compare the different proposed estimation methods. Example in real data is used as practical application of the proposed procedure.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1233-1237
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• 2001

A study was conducted to determine the effects of maturity at harvest and wilting days on the quality of round baled rye (Secale cereale L.) silage. This study was a $3{\times}3$ factorial arrangement in a split plot design with 3 replicates. The main plot was 3 harvesting dates at the stage of boot (20 Apr.), heading (29 Apr.) and flowering (14 May). The subplot was wilting day : 0 (unwilted), 0.5 and 1 day (0, 1, and 2 days at boot stage). Acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents of rye silage were significantly greater than those of rye before ensiling, but crude protein (CP) content and in vitro dry matter digestibility (IVDMD) were vice versa. Buffering capacity (BC) of rye harvested at flowering stage was decreased from 264 to 202 meq/kg at 1 day wilting, however, it was increased when harvested at boot or heading stage. The pH in wilted silage was the highest while that of flowering stage was the lowest. Water soluble carbohydrate (WSC) content of wilting rye was lower than that of unwilted, and the lowest at late harvesting stage. All plots had minimal WSC content for silage fermentation. Wilting treatment and delayed harvesting date caused an increase in dry matter (DM) content of round bale silage. The content of ammonia-N expressed as a portion of total N showed negative correlation with DM content. High quality silage according to ammonia-N content could be obtained from mid-harvest with wilting. There were highly significant differences in each organic acid between harvesting dates and wilting periods. Acetic and butyric acid contents were increased with delayed harvesting and prolonged wilting period, the lactic acid content, however, was decreased. This study demonstrated that harvest of rye from heading to flowering stage with wilting would be a recommendable method for making high quality rye silage using round bale system.

• Journal of Animal Science and Technology
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• 제47권5호
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• pp.877-890
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• 2005

본 시험은 보리호밀연맥 및 밀 4가지의 맥류에 있어서 수확시기가 사일리지의 재료적 특성과 제조한 사일리지의 품질에 미치는 영향을 조사하고자 실시하였다. 사일리지의 제조는 4회(수잉기출수기개화기황숙기)의 수확시기별로 실시하였다. 각 맥류는 위의 4처리 2반복으로 소형 비닐 백에 각각 1kg 정도의 재료를 넣어 진공포장하여 40일간 발효시켰다.사일리지 재료의 조성분은 수잉기에서 출수기개화기황숙기로 진행되면서 수분 및 조단백질 함량은 감소하고, NDFADFhemicellulose 함량은 증가하는 경향을 나타내었다. 수용성 탄수화물의 경우 전체 시험구에서 수잉기에서 황숙기로 진행되면서 과당 및 포도당의 함량이 유의하게 감소하였다. 사일리지 재료의 초산 함량은 각 생육단계에 따라 일정한 경향을 보이지 않았다. 사일리지 재료의 pH는 전체적으로 5.91-6.01의 범위였으며, 초종간 및 생육단계별로 유의한 차이가 없었다. 그리고 완충력은 전 처리구에서 건물기준 23.23-29.47meq/ 100g의 범위를 나타내었으며, 생육단계가 진행됨에 따라 감소하는 경향을 나타내었다. 제조된 사일리지의 조성분은 생육단계가 진행됨에 따라 전 초종에서 수분조단백질이 함량은 감소하는 경향을 나타냈으며, 섬유소의 함량은 증가하는 경향을 보였다. 생육단계가 경과됨에 따라 조제된 사일리지의 pH는 각 초종에 따라 다소의 차이는 있으나 높아지는 경향이었으며, 초산과 낙산 및 젖산의 함량은 전체적으로 감소하는 경향을 보였다. 그리고 완충력은 각 초종의 생육단계가 경과됨에 따라 감소하는 경향을 나타내었다. 따라서 맥류 사일리지의 제조시 이러한 재료적 특성을 잘 활용하는 것이 양질의 사일리지를 제조하는데 효율적인 하나의 방법이라고 사료된다.