• 한국물환경학회지
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• 제26권2호
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• pp.297-302
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• 2010

It is very important to know mean and confidence interval of water-quality constituents such as BOD for water-quality control and management of rivers and reservoirs effectively. The mean and confidence interval of BOD at Anseong2 and Hwangguji3 sampling stations which are located at the border of local governments in Anseong Stream were estimated and analyzed in this paper using Bootstrap technique which is one of non-parametric statistics. The results of Bootstrap were compared with arithmetic mean, geometric mean, Biweight method mean as a point estimator and distribution mean came from the appropriate probability distribution of Log-normal. In Bootstrap technique 12 data set was randomly selected in each year and 1000 samples was produced to get parameter of population. Visual Basic for Applications (VBA) of Microsoft Excel was utilized in Bootstrap. It was revealed that the Bootstrap technique can be used to explain more rigorously and robustly the achievement or violation of BOD target concentration in Total Maximum Daily Load (TMDL).

• 한국수학교육학회지시리즈D:수학교육연구
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• 제13권2호
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• pp.109-122
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• 2009

This study investigates the change in two theoretical constructs, attitudes toward mathematics and mathematics self-efficacy, among college students involved in a learning community model. The case of this study was a developmental mathematics class offered at a historically black college located in the southeastern United States. Subjects included 31 students enrolled in an introductory mathematics course, some of whom participated in a learning community (treatment group). The participants completed mathematics attitudes and mathematics efficacy instruments twice: at the beginning of the semester and again at the end. Data was analyzed using descriptive statistics and a non-parametric statistic. The results showed that students' attitudes toward mathematics and mathematics self-efficacy are strongly correlated; the mathematical problem-solving efficacy changed significantly over time and it is significantly higher in the treatment group than in the control group; and the treatment group produced better outcomes. These findings indicate that a learning community model can increase students' mathematics self-efficacy beliefs. It is recommended that mathematics self-efficacy and attitudes toward mathematics be measured over an extended period of time when a learning community is implemented.

• Journal of applied mathematics & informatics
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• 제32권3_4호
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• pp.343-357
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• 2014

In many non-life insurance applications past data are given in a form known as the run-off triangle. Smoothing such data using parametric crisp regression models has long served as the basis of estimating future claim amounts and the reserves set aside to protect the insurer from future losses. In this article a fuzzy counterpart of the Hoerl curve, a well-known claim reserving regression model, is proposed to analyze the past claim data and to determine the reserves. The fuzzy Hoerl curve is more flexible and general than the one considered in the previous fuzzy literature in that it includes a categorical variable with multiple explanatory variables, which requires the development of the fuzzy analysis of covariance, or fuzzy ANCOVA. Using an actual insurance run-off claim data we show that the suggested fuzzy Hoerl curve based on the fuzzy ANCOVA gives reasonable claim reserves without stringent assumptions needed for the traditional regression approach in claim reserving.

• 한국문헌정보학회지
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• 제43권1호
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• pp.113-133
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• 2009

이 연구는 대학도서관 이용자 특성과 연계한 전자책 대출기록 분석하여, 대학도서관 전자책서비스의 낮은 이용에 대한 원인을 분석하고 전자책서비스 활성화 방안을 제시하였다. 이의 분석방법으로 기초분석은 빈도분석과 기술통계를 사용하였으며, 성별과 전공분야별로 평가항목 간에 유의한 차이가 있는지를 분석하기 위해 t-test, ANOVA, 교차분석($X^2$) 및 상관관계를 사용하였다.

• 응용통계연구
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• 제31권1호
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• pp.41-65
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• 2018

우리나라의 경우 선진국에 비해 짧은 기간 동안 사망률 개선이 급속히 이루어짐에 따라 사망률 예측에 있어 모형의 선택뿐만 아니라 시계열 이용기간의 선정 또한 중요한 고려사항이 될 수 있다. 따라서 본 연구에서는 시계열 이용기간의 선택 관점에서 회귀모형을 이용하는 방법을 제안하였다. 또한 Lee-Carter (LC) 모형, LC류 (Lee-Miller (LM), Booth-Maindonald-Smith (BMS)) 그리고 비모수 모형(functional data model (FDM), Coherent FDM)을 토대로 시계열 이용기간을 다르게 적용할 경우 어떠한 문제가 발생되며, 연령별 사망률과 기대수명 예측력에 어떠한 차이를 보이는지 살펴보았다. 분석결과를 바탕으로 5개의 모형별 2030년까지 남녀의 연령별 사망률과 예측기대수명을 작성하고 통계청(Korean Statistical Information Service; KOSIS)에서 제공하는 장래 연령별 사망률과 기대수명과 비교하였다.

• Journal of the Korean Data and Information Science Society
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• 제21권6호
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• pp.1181-1190
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• 2010

보험회사가 보험계약자들의 적절한 보험료를 산출하는 것은 회사나 계약자들 모두에게 중요한 문제이다. 보험료를 결정하는 방법에는 보험회사가 보유하고 있는 매뉴얼에 근거하여 계약자들마다 같은 보험료를 부과하는 방법, 보험계약자 개인이나 집단에 관한 과거 기록에 바탕을 두어 보험료를 차등하여 정하는 방법, 그리고 위 두 가지 방법을 조합하여 보험료를 산정하는 방법 등이 있다. 이중 통계적인 모형에 기반을 둔 보험료 산정 방법에는 최대 정확도 신뢰도 이론이 있고, 이에 바탕을 둔 구체적인 접근법에는 뷸만 모형과 뷸만-스트라웁 모형 등이 있다. 본 논문에서는, 뷸만-스트라웁 모형을 확장하여, 자료 수가 늘어나면서 자료 평균의 변동성이 기대한 것보다 커지는 Hewitt의 아이디어를 반영한 모형에서, 새로운 비모수적 보험료 추정법을 제안한다. 또, 제안된 추정법을 모의자료에 적용해보고, 기존의 뷸만-스트라웁 추정량과 비교해본다.

• International Journal of Internet, Broadcasting and Communication
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• 제9권3호
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• pp.70-77
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• 2017

Dynamic visual acuity is used as an important factor to measure athletic performance in sports field. A study on visual acuity testing system using non-see head mounted display (NST-HMD) was conducted recently. However, the NST-HMD has a problem that the sense of space felt by the subject differs from the actual environment. This is because the view is blocked so that it is only implemented in a virtual space. This paper proposes a dynamic visual acuity testing system using optical see through head mounted display (OST-HMD). To do this, OST-HMD and NST-HMD comparative tests were conducted using existing K-D (King-Devick) charts. Experiments were performed on 30 subjects and their visual acuity was measured and analyzed by parametric statistics and one-sample T-test. The results of the study demonstrate the effectiveness of the proposed OST-HMD. This study is expected to use the visual inspection and training equipment of OST-HMD.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권1호
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• pp.392-412
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• 2018

Due to the semantic gap problem across different modalities, automatically retrieval from multimedia information still faces a main challenge. It is desirable to provide an effective joint model to bridge the gap and organize the relationships between them. In this work, we develop a deep image annotation and classification by fusing multi-modal semantic topics (DAC_mmst) model, which has the capacity for finding visual and non-visual topics by jointly modeling the image and loosely related text for deep image annotation while simultaneously learning and predicting the class label. More specifically, DAC_mmst depends on a non-parametric Bayesian model for estimating the best number of visual topics that can perfectly explain the image. To evaluate the effectiveness of our proposed algorithm, we collect a real-world dataset to conduct various experiments. The experimental results show our proposed DAC_mmst performs favorably in perplexity, image annotation and classification accuracy, comparing to several state-of-the-art methods.

• 지역사회간호학회지
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• 제12권1호
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• pp.202-213
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• 2001

This study was conducted to identify the changes of the relationship among general characteristics, self-efficacy. and self-care of the hypertensives in rural area. For this purpose, self-regulation program was carried at two Community Health Practitioner Post located in the suburbs of Daejeon City from September to November. 1999. Data were analyzed with non-parametric statistics, t-test, pearson correlation. The results were as follows; 1. The level of self-care was significantly different according to sex, status of smoking, and the level of self-efficacy of non-smoker was significantly higher than smoker. 2. After self-regulation program, there were significant positive relationship among self-efficacy, self-care, internal locus control, and negative relationship between perceived barrier and self-care. From these results, it can be concluded that the self-regulation program is an effective nursing strategy to promote self-care performance of hypertensives in rural area, and this program can be recommended for the management of hypertensives.

• Coupled systems mechanics
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• 제3권2호
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• pp.147-170
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• 2014

In the recent times, dimensions of heavy load carrying vehicle have changed significantly incorporating structural flexibility in vehicle body. The present paper outlines a procedure for the estimation of bridge response statistics considering structural bending modes of the vehicle. Bridge deck roughness has been considered to be non homogeneous random process in space. Influence of pre cambering of bridge surface and settlement of approach slab on the dynamic behavior of the bridge has been studied. A parametric study considering vehicle axle spacing, mass, speed, vehicle flexibility, deck unevenness and eccentricity of vehicle path have been conducted. Dynamic amplification factor (DAF) of the bridge response has been obtained for several of combination of bridge-vehicle parameters. The present study reveals that flexible modes of vehicle can reduce dynamic response of the bridge to the extent of 30-37% of that caused by rigid vehicle model. However, sudden change in the bridge surface profile leads to significant amount of increment in the bridge dynamic response even if flexible bending modes remain active. The eccentricity of vehicle path and flexural/torsional rigidity ratios plays a significant role in dynamic amplification of bridge response.