• 한국통계학회:학술대회논문집
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• 한국통계학회 2002년도 춘계 학술발표회 논문집
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• pp.19-24
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• 2002

The two-way balanced one-level rotation design has been discussed (Park, Kim and Choi, 2001), where the two-way balancing is done on interview time in monthly sample and rotation group. We extend it to three-way balanced multi-level design under the most general rotation system. The three-way balancing is accomplished on interview time not only in monthly sample and rotation group but also in recall time. We present the necessary condition and rotation algorithm which guarantee the three-way balancing. We propose multi-level composite estimators (MCE) from this design and derive their variances and mean squared errors (MSE), assuming the correlation from the measurements of the same sample unit and three types of biases in monthly sample.

• 응용통계연구
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• 제8권1호
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• pp.1-7
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• 1995

표본조사에서 추정하고자 하는 모비율이 낮으면 많은 표본을 추출해야 한다. 이 때 단위표본의 비용이 높아 추출할 수 있는 표본의 크기가 제한된다면 추정량의 분산을 줄일 수 있는 방법을 신중히 고려해야 할 것이다. 본 논문에서는 모집단에 대한 사전 정보가 있어 이를 이용하여 층화추출하는 경우에 층의 표본크기의 새로운 배분방법을 제안하고 기존의 배분방법들과 비교해 본다.

• Journal of the Korean Statistical Society
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• 제32권3호
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• pp.245-259
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• 2003

The 2-way balanced one-level rotation design has been discussed (Park et al., 2001), where the 2-way balancing is done on interview time in monthly sample and rotation group. We extend it to 3-way balanced multi-level design to obtain more information of the same sample unit for one or more previous months. The 3-way balancing is accomplished not only on interview time in monthly sample and rotation group but also on recall time as well. The 3-way balancing eliminates or reduces any bias arising from unbalanced interview time, rotation group and recall time, and all rotation groups are equally represented in the monthly sample. We present the rule and rotation algorithm which guarantee the 3-way balancing. In particular, we specify the necessary and sufficient condition for the 3-way balanced multi-level rotation design.

• 분석과학
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• 제27권6호
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• pp.284-291
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• 2014

차량 실내 공기질 대응 프로세스는 두 단계의 시험 방법으로 이루어져 있다. 먼저 모듈 부품평가를 통해 차량 실내 VOCs의 주요 원인을 찾고, 절단 시험편을 이용하여 VOCs가 주로 방출되는 소재를 찾는다. 만약 VOCs가 주로 방출되는 소재를 확인 시, 소재 개선을 통해 차량과 모듈 부품에서 방출되는 VOCs를 줄일 수 있다. 하지만 기존의 절단 시험편을 이용한 시험법은 VOCs 원인을 찾는데는 절단면에서의 방출 문제가 있기 때문에, 구성 부품 단위의 평가방법 적용이 필요하다. ISO 12219-5 시험 방법은 부품 절단없이 평가를 하기 때문에 소재 및 표면적의 영향이 함께 고려되어, 모듈 부품에서 구성 부품의 VOCs 영향도 확인이 가능하였다. 트림과 콘솔의 구성부품 평가를 통해 모듈내의 주요 원인 부품을 확인할 수 있었다. 또한 ISO 12219-5 모듈 부품 시험법과 구성 부품 시험법간의 정량적 상관관계 규명을 통해 품질관리를 위한 관리값을 설정할 수 있었다.

• 한국비블리아학회지
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• 제33권4호
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• pp.27-47
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• 2022

이 연구의 목적은 교육과정과 연계할 수 있는 교과 단원목록 시스템의 개발에 있다. 연구방법은 먼저 중학교 교육과정과 과학과 전 학년의 교과서 분석을 통해 단원 주제어를 추출하였다. 이를 바탕으로 교과의 단원주제와 관련된 도서를 연결하여 단원 도서목록, 단원주제어를 색인어로 정리한 색인어목록, 그리고 단원주제와 연계된 학년 및 학교급 연계목록을 하부 시스템으로 하는 단원목록 시스템을 설계하였으며, Notion 프로그램을 활용하여 중학교 과학 1단원을 표본으로 웹상에서 단원목록 시스템을 구현하였다. 시스템 평가를 위해 학생들을 대상으로 실험 및 설문 조사를 하였으며, 시스템 만족도 및 추후 활용 의향 등에서 매우 긍정적인 결과를 보였다. 한편 이 연구는 중학교 과학과를 대상으로 한정하였지만 전체 학년 및 교과로 확대 적용할 것을 제안하였다.

• 동서간호학연구지
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• 제23권1호
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• pp.45-52
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• 2017

Purpose: This study was to identify the effects of self-resilience and social support on reality shock among new graduate nurses. Methods: The data was collected using self-reported questionnaires from a convenience sample of 111 new graduate nurses. The data was analyzed by descriptive statistical, independent t-test, ANOVA, Scheffe test, Pearson correlation coefficient, and multiple regression via the SPSS Window 23.0 program. Results: Among general and work related characteristics, factors that have shown significant differences on reality shock were gender (t=-2.29, p=.024), work unit (t=3.31, p=.023) and whether they are working at unit they desired (t=-5.08, p<.001). Reality shock has shown a negative correlation with self-resilience (r=-.51, p<.001) and social support (r=-.41, p<.001). Factors that affected the reality shock on new graduate nurses were self-resilience (${\beta}=-.43$, p<.001), whether they are working at unit they desired (${\beta}=.35$, p<.001) and their currently work unit (${\beta}=-.17$, p=.028). These factors take into account of 38.0% of overall reality shock. Conclusion: The results suggest that self-resilience, desired unit and current work unit should be considered as factors when developing an intervention to alleviate the reality shock experienced by new graduate nurses.

• 한국직업건강간호학회지
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• 제32권3호
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• pp.99-110
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• 2023

Purpose: This study examined the job stress and perception of unit managers' authentic leadership on clinical nurses' intention to stay in nursing. Methods: This descriptive cross-sectional study utilized self-administered questionnaires. The study recruited a convenience sample of 211 clinical nurses from threertiary hospitals in South Korea. The survey was conducted between July and August 2021. The collected data underwent hierarchical multiple regression analyses. Results: The regression analyses indicated that clinical nurses' intention to stay was significantly associated with job stress (B=-0.06, 95% CI [-0.09, -0.04]), six or more years of clinical practice (B=0.60, 95% CI [0.13, 1.07]), men (B=0.87, 95% CI [0.30, 1.44]), and being placed on their desired nursing unit (B=0.39, 95% CI [0.27, 0.76]). Intention to stay was not found to be associated with authentic leadership by the unit managers. Conclusion: It is essential to implement workplace health promotion programs to prevent and reduce job stress among nurses to retain proficient clinical nurses. Additionally, nursing workforce management strategies tailored to the specific sex and career path of nurses are necessary. Moreover, careful consideration should be given to nursing unit placements that align with the individual aptitudes of nurses.

• 유통과학연구
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• 제17권4호
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• pp.77-85
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• 2019

Purpose - Statistics of Traditional Market is the only source of information on traditional markets, shopping street, and underground shopping street. The government conducts a survey of traditional market conditions every year to look at the current status of traditional markets and provide effective support. Therefore, this study examines the necessity and validity of updating about the Survey Population of Traditional Market Research design, data, and methodology - This study investigated the necessity of updating about the Survey Population of Traditional Market through literature review. Therefore this study examined the necessity of the current population based on the review of the population related to the sample design, methods, and the sampling frame. Next, we examined the change patterns of the population and the sample by dividing the population and sample of the current survey of the traditional market survey into the market unit, the store unit within the market, and finally the individual store unit. Results - As a result, the population of traditional market changes about 4~6%. Next, the analysis of the store unit in the market shows that the number of stores is very variable even though the market is continuously included in the survey target. Finally, as a result of examining the characteristics of individual stores, the stores with less than one year were more than 6% of the total surveyed stores based on the traditional market. These results are generally inconsistent with the idea that stores in traditional markets will operate for a long time in one place. Next, we proposed the establishment of a management system, applying Citizen Generated Data, and circulation survey. Additionally, this study proposes to change the stratification variables at the regional level rather than the market unit. Conclusions - Therefore, in this study, it is suggested that a current population of traditional market is needed updating, and that a population survey should be updated at least four years. In addition, a system for investigating traditional markets and districts was established and a circulation survey was proposed for efficient use of budgets. Based on these research results and policy suggestions, the future research directions are suggested.

• 대한교통학회지
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• 제4권2호
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• pp.37-58
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• 1986

Since 1960's there have been conducted quite numbers of origin and destination (0-D) surveys in Korea, Most of them, however, were to be said not so successful. In this paper, it was investigated that why the previous 0-D surveys were failed, and that how it could be improved. The findings of this study are: 1. The collection of sample data itself was performed relatively well, but the problem was in the improper expansion methods which were applied. 2. To improve the expansion methods, it should be performed not only the dwelling unit-based sample surveys but also commercial vehicle survey, cordon line survey, screen line counts and other auxiliary travel surveys like transit patronage survey, vehicle miles survey etc. at the same time. 3. To expand the sample surveyed data in a proper way, the adjustment factors should take a disaggregate form and also should be applied not to the specific trips, but to the specific trip makers to avoid the bias which could be caused by the application of adjustment factors in a way that has been used previously. 4. If there is no considerable change in travel patterns, we can synthesize the present 0-D data with past surveyed sample data, using present statistic data in the same way which was developed in this paper when expanding and adjusting sample data.

• ALGAE
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• 제24권2호
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• pp.111-120
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• 2009

Choosing an appropriate sample unit is a fundamental decision in the design of ecological studies. While numer-ous methods have been developed to estimate organism abundance, they differ in cost, accuracy and precision.Using both field data and computer simulation modeling, we evaluated the costs and benefits associated with twomethods commonly used to sample benthic organisms in temperatc kelp forests. One of these methods, theTargeted Sampling method, relies on different sample units, each "targeted" for a specific species or group ofspecies while the other method relies on coefficients that represent ranges of bottom cover obtained from visual esti-mates within standardized sample units. Both the field data and the computer simulations suggest that both meth-ods yield remarkably similar estimates of organisnm abundance and among-site variability, although the Coefficientmethod slightly underestimates variability armong sample units when abundances are low. In contrast, the twomethods differ considerably in the effort needed to sample these communities; the Targeted Sampling requiresmore time and twice the persormel to complete. We conclude that the Coeffident Sampling metliod may be bettcrfor environmental monitoring programs where changes in mean abundance are of central conccm and resources arelimiting, but that the Targeted sampling methods may be better for ecological studies where quantitative reIation-ships among species and small-scale variability in abundance are of central concern.