• Title/Summary/Keyword: 모평균에 대한 신뢰구간

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Travel time measurement using sensor loader system (센서부자 시스템을 이용한 도달시간 계측)

  • Hwang, Eui-Ho;Lee, Eul-Rae;Kim, Jeong-Yup;Choi, Hyuk-June
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.310-310
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    • 2011
  • 본 연구에서는 금강의 평수기 하류 평균도달시간을 산정하고 이를 통해 이수, 치수, 환경적인 측면을 고려하여 유역의 유하량별 하류지점의 도달시간을 실측하고, 측정 자료를 근거로 하여 수학적모델링을 통해 지류 및 본류의 시나리오별 유출량-평균도달시간 관계를 분석하여 수자원의 개발 이용과 보전, 관리를 위한 기초자료를 제공하고자 하였다. 이를 위해 하천 전 구간에서 실측할 수 있는 센서기술을 활용하였으며, 활용한 센서부자를 이용하여 금강의 금남보~공주대교 구간에 대하여 계측을 수행하였다. 계측결과 유출량-평균도달시간에 영향을 미치는 요인으로는 하상경사, 하폭, 지류유입량, 강우량, 식생, 하천구조물 등이 있으며, 이러한 요인을 수리학적 모형을 적용하여 모든 사상에 대해 정확한 해석을 한다는 것은 매우 어려운 일이다. 이로 인해 유출량-평균도달시간과의 관계 분석을 위해서는 많은 계측이 수반되어야 하며, 계측 결과를 토대로 각 하천별 유출량별 평균도달시간 관계에 대한 정확한 해석 방법을 제안하고자 하였다. 본 연구의 계측결과는 평 갈수기 수질사고로 인한 위기상황 대처시 도달시간 참조 자료로 활용이 가능할 것이며, 향후 지속적인 예측을 위해 수치모형의 매개변수를 보정하여 신뢰성 높은 도달시간표 제작이 가능하다. 또한, 기존 홍수예보 자료를 보완할 수 있는 유비쿼터스 기반 실측기술을 개발하고 이를 적용할 수 있는 기반을 구축함으로써 홍수예보의 신뢰성을 확보하고 홍수기댐 운영의 효율성을 확보할 수 있을 것으로 기대된다.

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A Note on Sometimes Pooling Rules (때때로 풀링의 규칙에 관한 소고)

  • Lim, Yong-Bin
    • The Korean Journal of Applied Statistics
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    • v.21 no.4
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    • pp.615-620
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    • 2008
  • In engineering experiments, 'Sometimes Pooling Rules' to remove insignificant terms from the model has been implemented to increase the power of detecting the small size of main effects when the preliminary test of higher order interaction effects declare to be insignificant. In this note, we review the sometimes pooling rules in the literature and also study the probability of the length of 95% confidence interval of ${\mu}_1-{\mu}_2$ of the comparison of two independent samples being shorter than that of the paired comparison at the various level of significance ${\alpha}_1$ of the preliminary test and the insufficient number of blocks n in [2,13], given the block effects being pooled to the error term. This study supports that the sometimes pooling results in the power improvement of the main effects.

Travel time measurement using sensor loader (센서부자를 이용한 하류 도달시간 계측)

  • Hwang, Eui-Ho;Lee, Eul-Rae;Kim, Jeong-Yup;Choi, Hyuk-June
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.714-714
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    • 2012
  • 금강 하류부의 경우 '97년 금강홍수예경보 자료를 활용하고 있으나, 수치모형 결과 자료로 실측에 의한 검증이 이루어지지 않았으며, 이러한 문제점을 해결하기 위해서는 평수기 및 홍수기의 하류도달시간 실측 기술을 확보하여 실측을 통한 수치모형의 검증 및 보완이 필요한 실정이다. 또한, 보정된 수치모형을 이용한 도달시간 실시간 예측을 통해 댐 보 운영의 효율성을 확보하고 대 내외에 검증 결과를 제시할 필요가 있다. 하천 전 구간에서 실측할 수 있는 센서기술을 활용하여 금강의 일부 보 구간에 대하여 계측을 수행하였다. 계측결과 유출량-평균도달시간에 영향을 미치는 요인으로는 하상경사, 하폭, 지류유입량, 강우량, 식생, 하천구조물 등이 있으며, 이러한 요인을 수리학적 모형을 적용하여 모든 사상에 대해 정확한 해석을 한다는 것은 매우 어려운 일이다. 이로 인해 유출량-평균도달시간과의 관계 분석을 위해서는 여러 하도구간에 대한 지속적이고 많은 계측이 수반되어야 하며, 이로부터 얻어진 계측 결과를 토대로 각 하천별 유출량별 평균도달시간 관계에 대한 해석 방법을 제안할 수 있을 것으로 기대한다. 본 연구의 계측결과는 홍수기 8회, 평수기 10회를 통해 보 건설에 따른 하류 도달시간의 영향을 분석하기에는 계측 자료가 매우 부족한 실정이며, 향후 지속적인 관측자료 확보를 통해서 보 운영에 따른 도달시간의 영향을 분석할 수 있는 기초자료 확보가 매우 중요할 것이다. 또한, 지류 유입량을 고려한 실측자료를 기초로 기존 도달시간 산정 방법을 개선하고, 도달시간 계측 결과의 신뢰성 확보를 위한 지속적인 연구개발 수행하여 금강 전 유역으로 확대 적용하기 위한 방안 마련이 필요하다. 이를 통해 4대강살리기 사업 전 후의 도달, 지체시간 분석하여 사업구간에 대한 계측을 통한 금강에서의 보 건설 전 후의 영향 검토에 반영할 수 있도록 하여 수계별 관계분석 자료로 활용할 수 있도록 제공하여야 할 것이다.

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Evaluation of Electrocardiographic Index in Healthy Raccoon Dogs (Nyctereutes procyonoides) (건강한 너구리(Nyctereutes procyonoides)들의 심전계 지표에 대한 평가)

  • Hong, Won-Woo;Kim, Jong-Taek;Yang, Dong-Keun;Nam, Hyo-Seung;Hyun, Changbaig
    • Journal of Veterinary Clinics
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    • v.30 no.6
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    • pp.456-458
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    • 2013
  • The aim of this study is to evaluate the reference value for electrocardiogram in healthy captive raccoon dogs. Forty-one free-ranging adult raccoon dogs rescued from Wildlife rescue centre, Kangwon National University were enrolled in this study. The 6-lead electrocardiogram was obtained in all raccoon dogs without any chemical restraints. The mean heart rate was $146.10{\pm}43.31$ beats/min (95% confidence interval 132.84~159.36 beats/min). The mean respiration rate was $35.73{\pm}11.56$ breaths/min (95% confidence interval 32.19~39.27 breaths/min). The mean systolic blood pressure was $136{\pm}29.26$ mmHg (95% confidence interval 127.99~145.91 mmHg). Electrocardiographical features were also evaluated in all raccoon dogs. The mean duration and amplitude of P-wave were $38.2{\pm}4.0$ ms (range 28-40 ms) and $0.128{\pm}0.039$ mV (range 0.09~0.20). The mean duration and amplitude of QRS complexes were $48.5{\pm}7.2ms$ (range 36-60 ms) and $1.330{\pm}0.650$ mV (range 0.15~2.30). The range of the mean electrical (QRS) axis was $-91^{\circ}{\sim}+96^{\circ}$ ($10^{\circ}{\sim}60^{\circ}$; 95% of confidence interval). The mean corrected QT (QTc) interval was $273.7{\pm}32.7ms$ (range 212-333 ms), while the mean PR interval was $76.1{\pm}10.0ms$ (range 50-82 ms). To the authors' knowledge, this is the first study to provide references in electrocardiogram (ECG) in healthy captive raccoon dogs.

Reliability Evaluation of Compressive Strength of Reinforced Concrete Members (철근 콘크리트 구조 부재의 압축강도 추정 신뢰도 평가)

  • Hong, Seong-Uk;Park, Chan-Woo;Lee, Yong-Taeg;Kim, Seung-Hun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.6
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    • pp.132-140
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    • 2019
  • In this study, a specimen composed of columns, walls, beams, and slabs was fabricated to investigate the estimated reliability using nondestructive test method for the location of structural members of reinforced concrete single layer structures. And for accurate analysis in the comparison process with the existing estimation formula, we try to analyze the reliability through statistical approach by using error rate comparison and Confidence interval estimation. As a result, The average error rate of the core test was 18.8% compared with the result of estimating the compressive strength using the ultrasonic pulse velocity method. The average error rate of the core test results compared with the result of estimating the compressive strength using the rebound hardness method was 20.1%, confirming the field applicability. it is judged that the reliability of the compressive strength estimation can be derived from the wall member to make a quick and efficient structure safety diagnosis using the ultrasonic pulse velocity method. In addition, it is judged that the reliability of the compressive strength estimation can be derived from the beam member to make a quick and efficient structure safety diagnosis using the rebound hardness method.

Effects of host modulation by nonsteroidal anti-inflammatory drugs on periodontal disease: a systematic review and meta-analysis (비스테로이드성 항염증제를 이용한 숙주조절이 치주질환에 미치는 영향: 체계적 고찰 및 메타 분석)

  • Kang, Dae-Young;Cho, In-Woo;Shin, Hyun-Seung;Ahn, Hyeong-Sik;Kim, Hyun-Jung;Park, Jung-Chul
    • Journal of Dental Rehabilitation and Applied Science
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    • v.33 no.1
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    • pp.7-18
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    • 2017
  • Purpose: Nonsteroidal anti-inflammatory drugs that prohibit biosynthesis of arachidonic acid metabolites have been considered potent host modulation agents. The aim of this review was to determine the effect of nonsteroidal anti-inflammatory drugs adjunctive with nonsurgical periodontal treatment in patients with periodontal disease. Materials and Methods: Three electronic databases were searched to identify relevant studies. The methodological quality and mean differences of the change in clinical attachment level and probing depth were analyzed according to Cochrane review methods. Results: Twelve studies were included in the methodological assessment and nine studies were suitable for inclusion in the meta-analysis. The mean difference in the clinical attachment level gain did not differ significantly between the nonsteroidal anti-inflammatory drugs and control groups at any observation time. The highest mean difference in clinical attachment level gain was 0.30 mm at 4 weeks (95% confidence interval = -0.37 to 0.97). There was a significant mean difference in the probing depth reduction, of 0.34 mm (95% confidence interval = 0.29 to 0.40) at 6 weeks. Conclusion: Therefore, nonsteroidal anti-inflammatory drugs have additional therapeutic effect when administrated with nonsurgical periodontal treatment.

A Travel Time Estimation Algorithm using Transit GPS Probe Data (Transit GPS Data를 이용한 링크통행시간 추정 알고리즘 개발)

  • Choi, Keechoo;Hong, Won-Pyo;Choi, Yoon-Hyuk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.5D
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    • pp.739-746
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    • 2006
  • The bus probe-based link travel times were more readily available due to bus' fixed route schedule and it was different from that of taxi-based one in its value for the same link. At the same time, the bus-based one showed less accurate information than the taxi-based link travel time, in terms of reliability expressed by 1-RMSE(%) measure. The purpose of this thesis is to develop a heuristic algorithm for mixing both sources-based link travel times. The algorithm used both real-time and historical profile travel times. Real-time source used 4 consecutive periods' average and historical source used average value of link travel time for various congestion levels. The algorithm was evaluated for Seoul urban arterial network 3 corridors and 20 links. The results based on the developed algorithm were superior than the mere fusion based link travel times and the reliability amounted up to 71.45%. Some limitation and future research agenda have also been discussed.

Application of Equivalent Ellipses for the Qualification of the Spatial Scale of Rainfall Event (호우사상의 공간규모 정량화를 위한 등가타원의 적용)

  • Kim, Ha-Young;Park, Chang-Yeol;Yoo, Chul-Sang
    • Journal of Korea Water Resources Association
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    • v.44 no.4
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    • pp.327-338
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    • 2011
  • This study examined the quantification problem of a storm shape using the concept of equivalent ellipses. The equivalent ellipses of a storm event were estimated at every time step with respect to the several thresholds of rainfall intensity, which was also examined in terms of their size and number. In addition, the average equivalent ellipse was decided, and the confidence intervals of major axis, minor axis, and rotational angle were calculated to evaluate if the average equivalent ellipse could be the representative one. As results, the following results could be derived. First of all, the number of equivalent ellipses and the size of equivalent ellipses increase as the threshold increase. Secondly, the appropriate ratio of major and minor axises of equivalent ellipse is 2 : 1. Finally, the average rotational angle estimated with respect to several threshold rainfall intensities were all found not to be statistically different from that of all representative rotational angles.

Evaluation of Antibodies Against Haemophilus influenzae Type b in Korean Adults (우리나라 성인에서 Haemophilus influenzae type b에 대한 항체 평가)

  • Lee, Ji Hyen;Kim, Han Wool;Lee, Soyoung;Kim, Kyung-Hyo
    • Pediatric Infection and Vaccine
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    • v.24 no.3
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    • pp.125-133
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    • 2017
  • Purpose: After the introduction of Haemophilus influenzae type b (Hib) vaccine in 1995 in Korea, it was included in the national immunization program in 2013. In the post-Hib vaccine era, some studies in other countries reported that invasive Hib disease affects adults, especially the elderly and immunocompromised persons, more often than it affects children. To evaluate disease susceptibility, quantitative and qualitative analysis of anti-polyribosylribitol phosphate (PRP) antibodies were carried out in Korean adults aged 20 to 85 years. Methods: Sera were collected from 39 healthy adults (20 to 50 years of age) and from 30 elderly adults (75 to 85 years of age) who did not have immune-compromising conditions. The concentration of anti-PRP immunoglobulin G (IgG) and serum bactericidal indices (SBIs) were measured by enzyme-linked immunosorbent assay and serum bactericidal assay. Results: Geometric mean concentrations of anti-PRP IgG and geometric mean SBIs were $0.88{\mu}g/mL$ (95% confidence interval [CI], 0.17 to 3.85) and 354 (95% CI, 50 to 2,499) in young adults and $1.67{\mu}g/mL$ (95% CI, 0.53 to 5.24) and 449 (95% CI, 146 to 1,376) in elderly adults, respectively. When the threshold of seropositivity for anti-PRP IgG was applied as 0.15 or $1.0{\mu}g/mL$, which is the protective antibody level in children, seropositive rates were 87.2% or 53.8% in young adults and 100% or 60% in elderly adults. The seropositivity rates of the SBI ($SBI{\geq}4$) were 82.1% and 100% in the groups, respectively. Conclusions: Most subjects in the adult and elderly adult groups display immunity to Hib based on quantitative and qualitative antibody levels, but not all. Because high immunization and low Hib circulation rates may reduce the natural Hib immunity in the population, monitoring Hib immunity as well as disease are needed continuously.

Bootstrapping Composite Quantile Regression (복합 분위수 회귀에 대한 붓스트랩 방법의 응용)

  • Seo, Kang-Min;Bang, Sung-Wan;Jhun, Myoung-Shic
    • The Korean Journal of Applied Statistics
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    • v.25 no.2
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    • pp.341-350
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    • 2012
  • Composite quantile regression model is considered for iid error case. Since the regression coefficients are the same across different quantiles, composite quantile regression can be used to combine the strength across multiple quantile regression models. For the composite quantile regression, bootstrap method is examined for statistical inference including the selection of the number of quantiles and confidence intervals for the regression coefficients. Feasibility of the bootstrap method is demonstrated through a simulation study.