• Communications for Statistical Applications and Methods
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• 제15권6호
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• pp.883-897
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• 2008

2006년 통계청이 시행한 광업 제조업 통계조사 결과(2005년 실적치)를 모집단으로 사용하면 최근 동향을 반영한 표본설계가 가능하다. 본 논문은 기존의 12개 업종보다 세분화된 94개 세부업종에 분류에 따라 매월 부품 소재산업의 생산, 출하, 재고의 변동사항을 조사하여 부품 소재산업의 경기변동실태를 파악하고 부품 소재산업의 육성정책 및 기업경영의 기초자료를 제공할 수 있는 새로운 표본설계를 제안한다. 표본설계는 응용절사법과 주성분을 이용한 다변량 네이만 배정법을 이용하여 층별로 표본크기를 결정하여 배정하고 표본추출은 확률비례계통추출을 사용한다.

• 응용통계연구
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• 제17권1호
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• pp.105-117
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• 2004

본 논문에서는 선형추세를 갖는 모집단의 평균을 추정하기 위한 새로운 방법을 제시하였다. 이 방법은 변형계통추출에 의하여 표본을 뽑은 뒤 표본의 단순평균이 아니라 조정된 추정량을 사용하여 모평균을 추정하는 방법이다. 조정된 추정량을 정하는 데에 최소제곱법을 사용하였다. 제시된 방법은 선형 추세가 강할수록 효율적이라는 것이 밝혀졌으며, 무한초모집단 모형의 랜덤오차항의 분산인 $\sigma$$^2$이 매우 크지만 않다면 전통적인 방법들에 비해 상대적으로 효율적인 것으로 나타났다.

• 동력기계공학회지
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• 제22권1호
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• pp.18-24
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• 2018

This paper focuses on systematic design about the membership ranges of the main design factors such as control error, control error rate, and sampling time for the fuzzy logic control of the variable speed drive refrigeration cycle. The upper and the lowest limit of the membership ranges are set up from the data of static characteristics obtained by experiments. Three kinds of membership ranges on the control error and the control error rate are tested by experiments. Especially, an effect of sampling time on control performance is also investigated in the same way. Experimental data showed the control error rate and the sampling time strongly effected on the control performance of the refrigeration cycle with a variable speed drive.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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• pp.1193-1196
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• 2003

This paper proposes a 2x oversampling method with a smart sampling for a clock and data recovery(CDR) circuit in a 2.5Gbps serial data link. In the conventional 2x oversampling method, the "bang-bang" operation of the phase detection produces a systematic jitter in CDR. The smart sampling in phase detection helps the CDR to remove the "bang-bang" operation and to improve the jitter performance. The CDR with the proposed 2x oversampling method is designed using Samsung 0.25${\mu}{\textrm}{m}$ process parameters and verified by simulation. Simulation result shows the proposed 2x oversampling method removes the systematic jitter.e systematic jitter.

• ETRI Journal
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• 제23권3호
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• pp.129-137
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• 2001

A random sampling or systematic sampling method is commonly used to assess the accuracy of classification results. In remote sensing, with these sampling methods, much time and tedious work are required to acquire sufficient ground truth data. So, a more effective sampling method that can represent the characteristics of the population is required. In this study, fractal analysis is adopted as an index for reference sampling. The fractal dimensions of the whole study area and the sub-regions are calculated to select sub-regions that have the most similar dimensionality to that of the whole area. Then the whole area's classification accuracy is compared with those of sub-regions, and it is verified that the accuracies of selected sub-regions are similar to that of whole area. A new kind of reference sampling method using the above procedure is proposed. The results show that it is possible to reduce sampling area and sample size, while keeping the same level of accuracy as the existing methods.

• 산업경영시스템학회지
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• 제8권11호
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• pp.85-95
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• 1985

This thesis is a study on the work sampling method which is one of the important parts in the fields of work measurement today. The primary objective of this study is to examine various methods of selecting observation times in work sampling studies, including simple random systematic, and stratified sampling and a new method called restricted random sampling. The attribute of these sampling methods are explained, particulary statistical efficiency, and the important advantages of stratification are analysed. A case study of work sampling was made in a manufacturing plant to show its practical application and the effectiveness of the stratified random sampling technique.

• 한국의료질향상학회지
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• 제29권2호
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• pp.85-93
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• 2023

Purpose: The predominant approach for mitigating inadequate sampling rates has primarily involved bolstering the volume of education. This study aimed to curtail inadequate sampling rates through the implementation of continuous quality improvement (CQI) activities, tailoring effective methods to the unique needs of each institution. Methods: We developed a sample handling guidebook and implemented QI activities to address this issue. Results: These measures resulted in a 4.7% decrease in inadequate sampling rates, concurrently improving knowledge of sample handling and overall nurse satisfaction. We addressed the root causes of inadequate sampling before laboratory pre-processing by: 1) focusing on systematic rather than erratic errors through CQI activities, 2) revising the sample handling guide, and 3) delivering face-to-face education based on the specific needs of the nursing department. These changes resulted in an additional 0.6% decrease in the inadequate sampling rate. Conclusion: This study demonstrates that the implementation of CQI activities based on evidence derived from a multifaceted causal analysis significantly reduced the inadequate sampling rate compared to previous studies.

• Communications for Statistical Applications and Methods
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• 제11권1호
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• pp.1-12
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• 2004

In this paper, Yates' end corrections method is centralized to estimate the mean of a population which has a linear trend in the case of k (the reciprocal of the sampling fraction) even. The efficiency of the resultant method is compared with that of existing methods.

• 산업경영시스템학회지
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• 제6권9호
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• pp.1-5
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• 1983

본 연구는 가동샘플링(Activity Sampling)에 대한 실태조사샘플링이론의 적용과 표준시간추정에 대한 가동샘플링의 적용에 대한 것으로, 집단·층별과 다단샘플링법을 무작위샘플링과 체계적 샘플링과 관련하여 연구했다. 정보를 최대화하기 위한 추정방법은 연구에 소요되는 비용에 따라 정해지며, 추정치의 정도를 추정하기 위한 절차의 규정도 고려했다. 전형적 작업로트의 생산자료로부터 표준요소작업수행시간을 추정하기 위해 다중회귀와 선형계획의 적용도 연구했다.

• 산업경영시스템학회지
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• 제26권4호
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• pp.12-22
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• 2003

The purposes of this study are to investigate the conformity of Korean Standards(KS) according to agreement on WTO/TBT, and to propose systematic frameworks of preparation, adoption, and application for KS in our enterprises. Significant changes in this establishment, revision, and abrogation include the following divisions; i) statistics-vocabulary and symbols, ii) Shewhart control chart, iii) statistical interpretation of data, iv) sampling procedures for inspection by attributes, v) sequential sampling plans for inspection.