• 품질경영학회지
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• 제46권3호
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• pp.651-658
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• 2018

Purpose: The algorithm described in Lim(1998) is available to determine the sample size directly given specified significance level, power and signal-to-noise ratio. We research on the efficient determination of the sample size by visual methods. Methods: We propose three graphs for investigating the mutual relationship between the sample size r, power $1-{\beta}$ and the detectable signal-to-noise ratio ${\Delta}$. First graph shows the relationship between ${\Delta}$ and $1-{\beta}$ for the given r and it can be checked whether the power is sufficient enough. Second graph shows the relationship between r and ${\Delta}$ for the given power $1-{\beta}$. Third graph shows the relationship between r and $1-{\beta}$ for the given ${\Delta}$. It can be checked that which effects are sensitive to the efficient sample size by investigating those graphs. Results: In factorial design, randomized block design and the split plot design how to determine the sample size directly given specified significance level, power and signal-to-noise ratio is programmed by using R. A experiment to study the split plot design in Hicks(1982) is used as an example. We compare the sample sizes calculated by randomized block design with those by split plot design. By using graphs, we can check the possibility of reducing the sample size efficiently. Conclusion: The proposed visual methods can help an engineer to make a proper plan to reduce the sample size.

• Journal of the Korean Statistical Society
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• 제14권1호
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• pp.48-55
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• 1985

In clinical trials subjects are avalible sequentially and must be assigned to treatments immediately. Completely randomized procedure for the allocation of treatments to each subject may result in severe imbalance among the number of subjects in treatment groups, especially for small experiments or interim analyses of large experiments. In this study, restricted randomization methods such as biased coin designs (Efron, 1971), permuted block design, and truncated binomial design are compared to teh completely randomized design in the presence of selection and/or accidential bias by Monte Carlo simulations.

• Journal of the Korean Statistical Society
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• 제15권1호
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• pp.9-25
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• 1986

In this paper we propose a distribution-free rank test for ordered alternatives in a randomized block design and investigate the properties of the proposed test. The proposed test is an extension of the Page test to allow replications in each cell. Some asymptotic properties including ARE's are investigated. A small sample Monte Carlo study was performed to compare the powers of the test considered in this paper for small samples. The results show that our proposed test is robust and efficient in the case of equally-spaced treatment effects.

• 응용통계연구
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• 제29권7호
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• pp.1421-1428
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• 2016

본 논문에서는 포장 재질에 따라 쌀의 신선도가 어떻게 달라지는지 알아보기 위해 다변량 분산분석을 적용해 보았다. 쌀의 신선도는 쌀의 수분 함량과 식미치로 측정하였다. 포장 재질은 일반 종이와 종이 뒷면에 숯을 코팅한 종이를 비교하였다. 쌀을 보관하는 장소를 블록으로 간주하였다. 쌀의 수분 함량과 식미치를 나타내는 이변량 관측값에 대하여 완전 확률화 블록 설계에 의한 다변량 분산분석을 적용해 본 결과 포장 재질에 따라 유의한 차이를 보였다. 따라서 쌀의 수분 함량과 식미치 각각을 단일변량 관측값으로 간주하고 분산분석을 적용해 보았다. 그 결과 쌀의 수분 함량에 대해서는 포장 재질에 따라 유의한 차이를 보였으나 식미치에 대해서 유의한 차이 관측할 수 없었다.

• Journal of the Korean Data and Information Science Society
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• 제22권2호
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• pp.245-253
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• 2011

블럭이 존재하는 $2{\times}2$ 요인모형의 주 효과 및 상호작용효과를 검정하기 위한 순위변환 통계량의 검정력은 블럭크기, 효과들의 구성방법 및 지수분포, 이중지수분포, 정규분포, 균일 분포를 포함한 모든 모집단 분포하에서 모수적 통계량의 검정력보다 월등한 우위를 보인다. 이는 블럭이 추가된 요인 모형은 블럭과 요인의 상호작용들이 오차항을 증가시켜 모수적 통계량의 검정력을 감소시키는 보수적 성향을 보이나, 순위변환 통계량의 검정력은 상대적 우위를 유지함에 기인한다고 유추할 수 있다. 일반적으로 블럭크기가 작고, 효과크기가 클수록 순위변환 통계량의 검정력은 모수적 통계량의 검정력보다 상당히 큰 격차의 상대적 우위를 보임을 알 수 있다.

• 응용통계연구
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• 제5권1호
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• pp.41-57
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• 1992

확률화 블록 계획법에서 우산형 대립가설에 대한 분포 무관 검정법을 제시하고 제안된 검정통계량의 점근적 성질과 모수적 방법과의 점근상대효율을 관찰하였다. 블록수가 4. 처리수가 5일 때와 블록수가 3, 처리수가 5일 때 주어진 정점이 2, 3, 4인 경우와 블록수가 2, 처리수가 4일 때 주어진 정점이 3인 경우에 소표본 Monte Carlo실험을 통하여 제안된 검정통계량과 Puri의 모수적 통계량의 실험 검정력을 구하였으며 제안된 검정통계량이 두터운 꼬리를 갖는 분포에서 효율적임을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권5호
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• pp.695-698
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• 2006

Six, one-year old dairy steers were randomly divided into two groups according to a Completely randomized design (CRD) to receive high-quality feed block (HQFB) without cassava hay and drenching (HQFB1+Ivomex) and HQFB with cassava hay (HQFB2) as block licks while grazing on Ruzi grass pasture. During the eight weeks, fecal parasitic egg counts dramatically declined for both treatment groups with 63.2 and 27.6% reduction from initial period for HQFB1+Ivomex and HQFB2, respectively. However, digestion of coefficients of nutrients particularly OM, were significantly higher in HQFB2 than, those in HQFB1+Ivomex, in addition, ADG of animals in HQFB2 tended to be higher than the group on HQFB1. It was, hence concluded that cassava hay could not only provide as a protein source but also serve as an anthelmintic in ruminants.

• 대한산업공학회지
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• 제29권2호
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• pp.179-189
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• 2003

Gate poly-silicon critical dimension is a prime characteristic of a metal-oxide-semiconductor field effect transistor. It is important to achieve the uniformity of gate poly-silicon critical dimension in order that a semiconductor device has acceptable electrical test characteristics as well as a semiconductor wafer fabrication process has a competitive net-die-per-wafer yield. However, on gate poly-silicon critical dimension, the complexity associated with a semiconductor wafer fabrication process entails hierarchical variance components according to run-to-run, wafer-to-wafer and even die-to-die production unit changes. Specifically, estimates of the hierarchical variance components are required not only for disclosing dominant sources of the variation but also for testing the wafer-level uniformity. In this paper, two experimental designs, a two-stage nested design and a randomized complete block design are considered in order to estimate the hierarchical variance components. Since gate poly-silicon critical dimensions are collected from fixed die positions within wafers, a factor representing die positions can be regarded as fixed in linear statistical models for the designs. In this context, the two-stage nested design also checks the wafer-level uniformity taking all sampled runs into account. In more detail, using variance estimates derived from randomized complete block designs, Duncan's multiple range test examines the wafer-level uniformity for each run. Consequently, a framework presented in this study could provide guidelines to practitioners on estimating the hierarchical variance components and testing the wafer-level uniformity in parallel for any characteristics concerned in semiconductor wafer fabrication processes. Statistical analysis is illustrated for an experimental dataset from a real pilot semiconductor wafer fabrication process.

• 한국산업정보학회논문지
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• 제19권3호
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• pp.57-66
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• 2014

본 논문은 RFID를 이용하여 환자, 의료진, 의약품을 관리하는 UHISRL(Ubiquitous Healthcare Information System based on Real Time Location)을 제안하였다. 제안하는 UHISRL은 환자의 건강상태를 모니터링하고, 그 결과를 스마트 폰과 태블릿 PC로 확인할 수 있다. 또한, 본 논문에서 설계된 ERHL(Extended Randomized Hash Lock) 인증 기법을 사용하여 재전송공격과 스푸핑 공격을 차단하였고, 환자의 프라이버시는 CP-ABE(Cipher Text - Attributed based Encryption)기법을 이용하여 UHISRL DB 접근을 속성에 따라 제한함으로써 보안을 강화시켰다. 특히, UHISRL는 만성질환자의 응급 상황을 실시간으로 모니터링 함으로써 불의의 사고를 방지할 수 있도록 하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권6호
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• pp.901-903
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• 1999

Twenty-four multiparous crossbred Friesian dairy cows (60-90 days in lactation) were randomly assigned into a $2{\times}2$ factorial arrangement in a randomized complete block design. Factors were two levels of concentrate supplementation (1:2, high vs 1:1.2, very high; concentrate:milk yield) and two levels of high-quality feed block (HQFB) supplementation (non vs ad libitum block licking). Ruzi grass (Brachiaria ruziziensis) was fed as a roughage throughout the 70 day feeding trial. High level of concentrate fed group resulted in higher roughage and HQFB intakes, compared with very high concentrate supplemented group. HQFB supplementation tended to increase roughage intake and significantly improved milk yield (2 kg/hd/d in high concentrate supplementation) and quality (% fat) which resulted in higher economical return. HQFB was recommended to be used as a strategic supplement in lactating dairy cows especially when fed on low-quality roughages or crop residues.