• 응용통계연구
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• 제24권3호
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• pp.477-484
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• 2011

반응/미반응 목표변수를 갖는 모집단에서 관심 목표범주의 빈도가 극히 작을 경우, 즉 희귀할(rare) 경우, 모형 구축을 위한 데이터마트를 형성할 때 반응/미반응 범주 구성비는 구축된 모형의 성능에 영향을 준다. 본 연구는 이러한 점에 착안하여 반응/미반응 범주 구성비와 모형성능의 관련성을 모형평가 통계량에 기반하여 판단한다. 이로써 데이터마트 형성에 이상적인 반응/미반응 범주 구성비를 탐지하려는데 본 연구의 목적을 두고 있다. 또한 일반적으로 목표범주의 빈도가 희귀할 경우, 분할 표본추출에 의하여 희귀사건(rare event)을 과대표본추출(oversampling)하는 것이 일반적이며, 이로부터 기인하는 사후확률에 대한 편향을 조정하게 된다. 본 연구에서는 사후확률 조정방법으로 오프셋(offset) 방법과 가중치 방법(sampling weights)을 적용하고 이를 비교하였다.

• 한국조사연구학회지:조사연구
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• 제9권2호
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• pp.29-49
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• 2008

설문조사에서 어떤 주제와 관련된 여러 항목들을 제시하고 응답자들의 가치 기준에 따라 응답하게 한 후, 그 응답들을 종합하여 항목들 간의 순위를 결정할 목적으로 설문을 제시하는 경우가 많이 있다. 이 경우 가장 일반적으로 사용하는 것이 순위척도(ranking scales)와 평정 척도(rating scales)이다. 순위척도 중에서도 주어진 항목들 중 가장 중요한 것을 하나 이상 선택하게 하는 축소순위척도(reduced ranking scales)가 많이 사용된다. 그러나 실제로 항목간의 순위를 결정하는 과정에서 순위응답을 고려하는 경우는 극히 드물다. 본 연구는 순위절차(ranking procedures)에 의한 설문응답에서, 순위응답을 고려하여 항목순위를 결정하는 방법들을 고찰하였다. 또 몇 가지 사례를 통해 그 방법들을 비교 분석하였으며, 이 과정에서 순위척도를 조건부평정척도로 간주하였다. 축소순위척도에 의한 항목순위결정의 경우, 1순위와 2순위 그리고 3순위에 각각 2와 1 그리고 0의 값을 부여함으로써 1순위의 응답비율을 희석하지 않으면서 2순위 응답비율을 적절히 수용하여 보다 합리적인 항목순위를 결정할 수 있음을 확인할 수 있었다.

• 한국항만경제학회지
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• 제35권1호
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• pp.117-138
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• 2019

세계적 수준인 우리나라 해운물류산업에 비해, 해운물류 연구 실적에 대한 평가는 다소 불분명하다. 본 연구는 우리나라 해운물류분야의 상위 30명의 연구자와 30개의 기관을 분석했다. 분석은 2000년부터 2015년까지 16년간 해운 및 운송 관련 65개 SSCI 및 SCI 학술지에 게재된 논문을 대상으로 했다. 순위를 산정하기 위해 다음과 같은 세 가지 지표를 사용했다: 1) 논문의 수, 2) 저자들의 기여도를 반영한 가중 점수(Weighted Score), 3) 학술지의 Impact factor를 고려한 영향력 점수. 시간의 흐름에 따른 각 기관과 연구자의 순위 변화를 5년을 주기로 측정했다. 또한, 우리나라 해운물류 연구가 세계 해운물류 분야에서 차지하는 비중을 분석하였다. 끝으로, 우리나라 연구자들의 방법론적 선호도를 세계 연구자들과 비교 및 분석하였다.

• 한국임상보건과학회지
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• 제5권1호
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• pp.790-802
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• 2017

Purpose. This study was designed to analyze recent trends in Children Art Therapy Program Intervention research in Korea and suggest future research directions in this area. Methods. Studies(29) selected from http://www.riss4u.net for last 15 year were used. They were analyzed by publication type, field and design of the study, study participants and outcome variables used in intervention studies. Results. 1. As for academic field, there are 15 art therapy academic journals(51.72%), which made up the largest proportion. 2. As for subjects of the study, there are 17 articles of Elementary (58.6%) education, which made up the largest proportion. As for the subjects of sex, 8 articles (27.59%) are for male students, 7 (24.14%) articles are for female students and 14 articles (48.28.%) are for both male and female students. 3. As for 7 articles of Art therapy(24.14%), 7 articles of Group Art therapy (24.14%) made up the largest proporton 4. As for the intervention study method according to the subjects of suicide intervention program, there are 15 articles of monoclonal Pre and post design (51.72%),which made up the largest proportion. 5. As for the sample size, there were 16.79 persons in the treatment group on average, 13.28 persons in the control group have average and the total persons were 10 on average. The treatment period was 12 weeks on average and the average number of treatment times was 18. The places of treatment were 3 schools (10.38%), which made up the largest proportion. 19. The results of the experimental study support the research hypothesis of all 29 programs. Conclusions. As the above, the studies on the art therapy intervention program for children are increasing but the subjects are overly weighted toward elementary school students. Although the content of the art therapy intervention program was varied, it was found that the development of the program using various art media which can induce the motivation of the child was lacking. In addition, the place of experimental mediation was concentrated on psychology center as 12(41.38%), indicating that there are not enough places to connect with community organizations such as schools and hospitals. The variables of experimental study were focused on psychological variables and it was found that there were insufficient application of various variables including coping method, social support, and physiological variables.

• Asian-Australasian Journal of Animal Sciences
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• 제30권9호
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• pp.1261-1269
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• 2017

Objective: The effect of flavonoids from alfalfa on the microbial flora was determined using molecular techniques of 16S ribosome deoxyribonucleic acid (rDNA) analysis. Methods: Four primiparous Holstein heifers fitted with ruminal cannulas were used in a $4{\times}4$ Latin square design and fed a total mixed ration to which alfalfa flavonoids extract (AFE) was added at the rates of 0 (A, control), 20 (B), 60 (C), or 100 (D) mg per kg of heifer BW. Results: The number of operational taxonomic units in heifers given higher levels of flavonoid extract (C and D) was higher than for the two other treatments. The Shannon, Ace, and Chao indices for treatment C were significantly higher than for the other treatments (p<0.05). The number of phyla and genera increased linearly with increasing dietary supplementation of AFE (p<0.05). The principal co-ordinates analysis plot showed substantial differences in the microbial flora for the four treatments. The microbial flora in treatment A was similar to that in B, C, and D were similar by the weighted analysis. The richness of Tenericutes at the phylum level tended to increase with increasing AFE (p = 0.10). The proportion of Euryarchaeota at the phylum level increased linearly, whereas the proportion of Fusobacteria decreased linearly with increasing AFE supplementation (p = 0.04). The percentage of Mogibacterium, Pyramidobacter, and Asteroleplasma at the genus level decreased linearly with increasing AFE (p<0.05). The abundance of Spirochaeta, Succinivibrio, and Suttonella at the genus level tended to decrease linearly with increasing AFE (0.05

• 대한지리학회지
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• 제46권2호
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• pp.197-211
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• 2011

공간 상호작용의 복잡성, 공간적 재현과 모델링의 필요성에 의해서 공간 상호작용 데이터의 합역이 불가피하다. 이러한 상황에서 본 연구의 목적은 공간 상호작용 데이터를 스케일을 달리하여 합역하거나 혹은 동일 스케일에서 합역 방식을 달리하여 합역하였을 때, 공간 상호작용 모델의 결과가 어떻게 달라지는지 평가하는 것이다. 공간 상호작용 데이터의 합역은 공간단위 수정가능성의 문제(Modifiable Areal Unit Problem: MAUP)를 야기한다. 공간 상호작용 데이터의 합역을 위하여 무작위로 구역 시드를 선정한 후 인접한 공간단위를 할당하는 방법, 구역 시드와 공간단위 사이의 연구 가중 거리를 최소화하는 방법, 구역 내 상호작용 비율을 최대화하는 방법, 구역 내 상호작용 비율을 최소화하는 방법을 사용하였다. MAUP의 영향을 평가하기 위한 공간 상호작용 모텔로 기원지-목적지 제약 포아송 회귀 모델을 이용하였다. 분석 결과는 모델 잔차의 공간적 특성뿐만 아니라 파라미터 추정값, 적합도 등이 MAUP의 영향을 받는다는 것을 보여주었다. 모델은 합역 방식 보다는 합역 수준에 더 민감하게 반응하였고, 모델에 대한 스케일 효과는 구획 방식에 따라 상이하게 나타났다.

• 통합자연과학논문집
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• 제5권4호
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• pp.241-245
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• 2012

Categorical data collected based on complex sample design is not proper for the standard Pearson multinomial-based chi-squared test because the observations are not independent and identically distributed. This study investigates effects of bias of point estimator of population proportion and its variance estimator to the standard Pearson chi-squared test statistics when the sample is collected based on complex sampling scheme. This study examines the effect under two population homogeneity test. The standard Pearson test statistic can be partitioned into two parts; the first part is the weighted sum of ${\chi}^2_1$ with eigenvalues of design matrix as their weights, and the additional second part which is added due to the biases of the point estimator and its variance estimator. Our empirical analysis shows that even though the bias of point estimator is small, Pearson test statistic is very much inflated due to underestimate the variance of point estimator. In the connection of design-based variance estimator and its design matrix, the bigger the average of eigenvalues of design matrix is, the larger relative size of which the first component part to Pearson test statistic is taking.

• Journal of Oral Medicine and Pain
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• 제25권1호
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• pp.63-71
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• 2000

The authors assessed if there is a relationship between joint effusion and the presence of pain, and between joint effusion and disc displacement in 446 temporomandibular joints of 223 subjects who visited the Department of Oral Medicine, Kyungpook National University Hospital with the complaints of temporomandibular joint problem. The amount of joint effusion and the position of disc were determined from magnetic resonance images of the temporomandibular joints. The position of disc was classified into normal disc position, disc displacement with reduction (DDWR), and disc displacement without reduction (DDWOR). The amount of joint effusion was graded according to the extent of joint area of high signal intensity on T2-weighted MR images. These findings were correlated with one another and statistically analyzed. The results were as follows; 1. The incidence of temporomandibular joint pain Was higher in the joints with higher amount of joint effusion (P<0.001). 2. The proportion of temporomandibular joints with higher amount of effusion increased in the joints with more advanced articular disc displacement (P<0.001).

• 한국임상수의학회지
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• 제20권1호
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• pp.59-65
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• 2003

This study was performed to investigate the immunopotentiative effects of conjugated linoleic acid on mice immunosuppressed by administratin corticoids. Mice were divided into four groups of 8 mice. Two groups (C, CP) were given diet supplemented with 1% linoleic acid (CLA) and the other two groups (L, LP) were given diet supplemented with 1% linoleic acid (LA) instead of CLA. Prednison was administered to two groups (CP, LP) for immune depression. After feeding diets for 3 weeks containing PDS injection for last 1 week. Serum and gut lumen lavage were taken. Measurement of total Ig were executed using sandwich ELISA. Serum levels of IgA, IgG, and IgM showed some trend which groups fed with CLA were higher than groups fed with LA while IgE was reduced in those fed the CLA intake, and groups administered with PDS were lower than groups administered with saline. However, no significant differences were seen in the proportion of total immunoglobulin in serum. In case of secretory IgA, Group C and CP were significantly higher than group L and LP. Especially between CP and LP, it can be seen effects of CLA. In addition that the CLA treated group weighted a significantly lower level than the one's that have not been treated with CLA. These result support the view that CLA potentiate the immune response and prevent immune depression caused by administrating of corticoids. In conclusion, CLA produced a situation favorable for immunopotentiative effects. Thus, the clinical application of CLA is warranted.

• Ocean and Polar Research
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• 제40권1호
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• pp.37-48
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• 2018

The purpose of this study is to assess the climate change vulnerability of coastal and offshore fisheries in the South Sea of Korea using the RCP scenarios. Based on the vulnerability defined by IPCC, the indicator-based method was applied. Exposure indicator was calculated through weighted sum of the sea temperature and salinity forecasted by National Institute of Fisheries Science, and the weights were obtained from the time-space distribution of each fisheries. Sensitivity indicator was determined by applying the catch proportion of fisheries to the sensitivity of fish species. The adaptive capacity was measured by survey of fisheries which represent the ability of the fishermen well. As a result of summarizing the above indicators, vulnerability of coastal fisheries is higher than offshore fisheries. This shows that measures against coastal fisheries are needed. In addition, the results of each scenario are somewhat different, so it is considered that accurate prediction of climate change is important for adaptation measures.