• 제목/요약/키워드: percentile.

검색결과 1,061건 처리시간 0.023초

비모수통계방법을 이용한 원자력발전소 작업자 반복성 고피폭작업 도출 (Use of Non-Parametric Statistical Method in Identifying Repetitive High Dose Jobs in a Nuclear Power Plant)

  • Young-Ho Cho;Young-Hoi Herr
    • 방사성폐기물학회지
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    • 제2권1호
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    • pp.41-51
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    • 2004
  • 원전 작업자 방사선량의 효과적인 저감을 위해서는 발전소 내에 축적된 작업자 피폭선량자료들을 분석하는 것이 반드시 필요하다. 자료의 분석을 통해, 발전소에서 수행되는 방사선작업들 중 반복적으로 고피폭을 유발하는 작업들을 파악하는 것이 필요하며, 본 연구에서는 이러한 반복성고피폭작업들을 도출하기 위한 방법론으로 백분위수 순위합 방법을 제안한다. 이는 비모수통계학 이론에 근거한 방법론으로, 본 연구에서는 이 방법을 이용하여 고리 3,4 호기 작업자 피폭선량 자료를 분석, 고피폭작업들을 도출하였다. 도출 결과는 통계적으로 검증되며, 그 결과 백분위수 순위합 방법의 효과 및 타당성을 입증하였다.

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재발성 호흡기 감염과 성장 부전을 보인 IgG 아형 결핍증 1례 (A Case of IgG Subclass Deficiency with Growth Failure)

  • 최용성;홍정미;나영호;차성호
    • Pediatric Infection and Vaccine
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    • 제13권2호
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    • pp.201-205
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    • 2006
  • 원발성 면역 결핍증에는 항체형성에 영향을 주는 질환이 가장 흔하고 그중 선택적으로 분비성 IgA 결핍이 많으나 IgG 농도가 정상 혹은 증가되어 있는 어떤 환자에서는 4가지의 IgG 아형 중에서 한 두 개 이상의 결핍이 발견된다. 대부분의 환자, 특히 IgG4 결핍증 환자에서 폐구균, 포도구균, 헤모필루스균 등에 의한 부비동염, 중이염, 폐렴 등이 반복된다. 상기 10세 여아는 평소에 잦은 상기도 감염을 앓아 왔고, 결핵성 림프절염으로 약물요법을 시행한 병력이 있으며, 매년 2~3차례 폐렴으로 입원치료를 받아왔다. 키와 몸무게가 모두 3백분위수 미만으로 성장부전(growth failure)가 지속되었다. 2003년 9월 심한 폐렴으로 입원 치료 중에 면역결핍 검사를 시행하였다. IgG, IgM level은 정상이었으나 IgG subclass 2, 3, 4에서 모두 감소된 수치를 보여 IgG 아형 결핍을 보였다. 저자들은 반복적인 호흡기 질환을 앓는 환아에서 성장부전이 동반된 IgG 아형 결핍 1례를 보고하는 바이다.

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임상 검사 결과로부터 정상 범위 추정에 대한 통계학적 연구 (Statistical Problems in the Determination of Normal Manges from Laboratory Data)

  • 송혜향
    • Journal of Preventive Medicine and Public Health
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    • 제17권1호
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    • pp.231-238
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    • 1984
  • 질병의 진단이나 예후를 판정함에 도움이 되고자 의학분야에서 정상 범위를 정의해 왔으며, 이 정의에 도입된 전통적인 통계적 방법으로는 정규 확률지를 사용하여 정상범위를 추정함이었다. 이 방법은 정상군과 질병군의 검사 성적 분포가 각각 정규 분포한다는 가정에서 시작되며, 이 가정이 보편적일 수 없음을 여러 연구(Elveback et al, 1970; Feinstein, 1977)에서 밝히고 있다. 또한 통계적 방법론중 일상 사용되고 있는 평균치로부터 두배의 표준 편차 거리로 나타 내어지는 구간을 정상 범위로 추정함은 비대칭 분포의 경우 합당치 못한 경우가 생기게 된다. 대칭과 비대칭의 분포에 합당하게 사용될 수 있는 방법은 백분율에 근거한 방법으로 특정한 의학적인 요구가 없는 한 균등한 하단과 상단의 백분율 구간을 정함이 상례였다고 보겠다. 그러나 높은 칼슘의 수치를 나타내 보이는 환자에게 주의가 필요함과 같이 특수한 의학적인 촉구에 의해 하단과 상단의 불균등한 백분율 지점을 정상범위로 선정할 수도 있으나 백분율의 표준 오차에 근거해서 정상 구간이 추정되어야 하겠다.

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Impact of Multiple Cardiovascular Risk Factors on the Carotid Intima-media Thickness in Young Adults: The Kangwha Study

  • Chang, Hoo-Sun;Kim, Hyeon-Chang;Ahn, Song-Vogue;Hur, Nam-Wook;Suh, Il
    • Journal of Preventive Medicine and Public Health
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    • 제40권5호
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    • pp.411-417
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    • 2007
  • Objectives: Although risk factors for coronary artery disease are also associated with increased carotid intima-media thickness (IMT), there is little information available on the asymptomatic, young adult population. We examined the association between multiple cardiovascular risk factors and the common carotid IMT in 280 young Korean adults. Methods: The data used for this study was obtained from 280 subjects (130 men and 150 women) aged 25 years who participated in the Kangwha Study follow-up examination in 2005. We measured cardiovascular risk factors, including anthropometries, blood pressure, blood chemistry, carotid ultrasonography, and reviewed questionnaires on health behaviors. Risk factors were defined as values above the sex-specific 75th percentile of systolic blood pressure, body mass index, total cholesterol/ high-density lipoprotein cholesterol ratio, fasting blood glucose and smoking status. Results: The mean carotid IMT${\pm}$standard deviation observed was $0.683{\pm}0.079mm$ in men and $0.678{\pm}0.067mm$ in women (p=0.567) and the evidence of plaque was not observed in any individuals. Mean carotid IMT increased with an increasing number of risk factors(p for trend <0.001) and carotid IMT values were 0.665 mm, 0.674 mm, 0.686 mm, 0.702 mm, and 0.748 mm for 0, 1, 2, 3, and 4 to 5 risk factors, respectively. The odds ratio for having the top quartile carotid IMT in men with 3 or more risk factors versus 0-2 risk factors was 5.09 (95% CI, 2.05-12.64). Conclusions: Current findings indicate the need for prevention and control of cardiovascular risk factors in young adults and more focus on those with multiple cardiovascular risk factors.

Validity of Self-Reported Height, Weight, and Body Mass Index of the Korea Youth Risk Behavior Web-Based Survey Questionnaire

  • Bae, Ji-Suk;Joung, Hyo-Jee;Kim, Jong-Yeon;Kwon, Kyoung-Nam;Kim, Yoon-Jung;Park, Soon-Woo
    • Journal of Preventive Medicine and Public Health
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    • 제43권5호
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    • pp.396-402
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    • 2010
  • Objectives: Self-reported anthropometric values, such as height and weight, are used to calculate body mass index (BMI) and assess the prevalence of obesity among adolescents. The aim of this study was to evaluate the validity of selfreported height, weight, and BMI of the Korea Youth Risk Behavior Web-based Survey questionnaire. Methods: A convenience sample of 137 middle school students and 242 high school students completed a selfadministered questionnaire in 2008. Body height and weight were directly measured after self-reported values were obtained from the questionnaire survey. Sensitivity, specificity, and kappa statistics were computed in order to evaluate the validity of the prevalence of obesity (BMI $\geq$ 95th percentile or $\geq$ $25;kg/$m^2$) based on self-reported data. Results: Self-reported weight and BMI tended to be underestimated. Self-reported height tended to be overestimated among middle school females and high school males. Obese adolescents tended to underestimate their weight and BMI and overestimate their height more than non-obese adolescents. The prevalence estimate of obesity based on selfreported data (10.6%) was lower than that based on directly measured data (15.3%). The estimated sensitivity of obesity based on self-reported data was 69.0% and the specificity was 100.0%. The value of kappa was 0.79 (95% confidence interval, 0.70 - 0.88). Conclusions: This study demonstrated that self-reported height and weight may lead to the underestimation of BMI and consequently the prevalence of obesity. These biases should be taken into account when self-reported data are used for monitoring the prevalence and trends of obesity among adolescents nationwide.

심리생리적 운전부하를 고려한 도로설계운전자 특성기준 정립연구 (A Study on development of Road Design Driver Characteristics based on Physio-Physiological Performance)

  • 김주영;박민수;김정룡;장명순
    • 대한교통학회지
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    • 제29권5호
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    • pp.67-78
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    • 2011
  • 본 연구에서는 30명의 피실험자를 대상으로 운전자의 운전부하 특성을 분석하였다. 설계운전자의 심리생리적 특성을 파악하고자 뇌의 후두엽부위 뇌파신호를 이용하여 시뮬레이션 실험과 현장주행 실험을 수행하였다. 본 연구를 통해 다음과 같은 결론을 도출하였다. 첫째, 운전자의 생체신호(뇌파)를 이용하여 설계운전자의 특성을 표현할 수 있었다. 둘째, 설계운전자의 운전부하 설명변수로는 베타파 값과 상대에너지 계수 값이 통계적으로 유의하였다. 셋째, 시뮬레이터 주행실험치의 90퍼센타 일 범위값이 설계운전자의 특성으로 적정한 것으로 분석되었다. 넷째, 실제 도로주행상황에서, 설계운전자의 최대 각성값은 베타파의 경우 31.72이며, 상대에너지계수 지표의 경우 1.296으로 분석되었다.

이식편의 측면접합이 복합조직이식의 생존에 미치는 영향 (The Effect of Lateral Approximations on the Survival of the Free Composite Flap)

  • 김덕우;박승하;이병일
    • Archives of Reconstructive Microsurgery
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    • 제16권2호
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    • pp.57-62
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    • 2007
  • Non-vascularized free composite graft is one of the simple and effective reconstructive options, but its clinical use has been limited due to questionable survival rate. Early vascularization is essential for graft survival and is mainly carried out via recipient bed or repaired sites. This study was designed to investigate the effect of the lateral marginal approximations on the survival of the free composite flap using a model of skin-subcutaneous composite graft in rats. Thirty 1.5 ${\times}$ 1.5 $cm^2$ sized square shape composite flaps were elevated freely and reposed in place immediately on the dorsum of five Sprague-Dawley rats, and divided into five groups of six flaps. In all groups, graft bed was isolated with silastic sheet. In the group I, all sides of flap were repaired with blockage of silastic sheet insertion. Three, two, and one sides of flap were treated with same method in the group II, III, and IV respectively. Other sides of flaps were repaired without blockage, so all sides of flap were repaired in the group V. At 14 days later, the survived rate of each flap was evaluated according to the numbers of the repair sites. Histological examination was done for the evaluation of new vessel development quantitatively. Overall survived rates were increased with the number of repaired sites, but the group V only showed increased survival rate up to more than fifty percentile of the flap size with a significant difference statistically. New vessels were also increased in proportion with the number of repaired sites, and the repair site more than two had significant effect on the increased number of new vessels. In conclusion, at least more than three-fourth of flap circumference should be repaired in order to increase flap survival effectively under the condition of bed isolation.

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우리나라의 오존도 변화 추이와 주요 인자 (Trends and Factors of Ozone Concentration Variations in Korea)

  • 김영성
    • 한국대기환경학회지
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    • 제16권6호
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    • pp.607-623
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    • 2000
  • Major trends of ozone concentration variations in Korea were investigated by using observation data from around 100 stations for the period of 1991∼1997. In addition, important regulating those variations were inferred. Three measures such as the number of days exceeding 80ppb, the 95th percentile of daily maxima, and the annual average concentration were used for the analysis of multi-scale ozone concentration variations. Three areas in the southwest (Sosan, Mokpo, and Cheju) of which monitoring has been operated since 1995 showed the highest annual average concentrations over; this was noted because of the high annual average in the Yosu area in the early 1990s. Large increases in annual average concentrations were observed along the relatively cleaner areas connecting Kangnung and Kwangju(northeast to southwest), in contrast to polluted areas connecting Seoul and Pusan(northeast to southeast). Both the number of exceedance days and the daily maximum concentration were nearly constant in the Greater Seoul Area in spite of interannual flucturations associated with year-to-year changes in air temperature. Within the Greater Seoul Area, all three measures usually showed the same trend; they decreased in the middle and west and increased in the east and northeast. All three measures including the number of exceedance days increased largely at Sillim where the average concentration was high but no exceedance days were recorded in the early 1999s, Nationwide ozone concentration variations appear to be determined by the competitive influence of long-range transport and local urban emissions, Within the city including the Greater Seoul Area, changes in emission which accompany changes in population and in the number if vehicles ( in the process of urban development) were found to be important components of ozone concentration variations.

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방사능위해성평가 프로그램 RADCONS의 개발 및 적용 (Development and Application of Radiological Risk Assessment Program RADCONS)

  • 정효준;박미선;황원태;김은한;한문희
    • 환경영향평가
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    • 제22권1호
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    • pp.89-97
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    • 2013
  • RADCONS Ver. 1.0 (RADiological CONSequence Assessment Program) was developed for radiological risk assessment in this study. A Gaussian plume model was used to analyze the fate and transport of radionuclides released into the air in case of accidents. Both single meterological data and time series meterological data can be used in RADCONS. To assess the radiological risk of the early phase after an accident, ED (Effective Dose) estimated by both deterministic and probabilistic approaches are presented. These EDs by deterministic and probabilistic will be helpful to efficient decision making for decision makers. External doses from deposited materials by time are presented for quantifying the effects of mid and late phases of an accident. A radiological risk assessment was conducted using RADCONS for an accident scenario of 1 Ci of Cs-137. The maximum of ED for radii of 1,000 meters from the accident point was 8.51E-4 mSv. After Monte-Carlo simulation, considering the uncertainty of the breathing rate and dispersion parameters, the average ED was 8.49E-4, and the 95 percentile was 1.10E-3. A data base of the dose coefficients and a sampling module of the meteorological data will be modified to improve the user's convenience in the next version.

식사기록과 인터뷰를 이용한 일부 저소득층 아동의 식사 구성 및 식행동 조사 (Assessment of Meal Quality and Dietary Behaviors of Children in Low-Income Families by Diet Records and Interviews)

  • 박은영;한성림;김혜경
    • 한국식품영양학회지
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    • 제24권2호
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    • pp.145-152
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    • 2011
  • This study was conducted to investigate the meal quality and dietary behaviors of low-income family children by qualitative method. The subjects were 12 children(2 boys and 10 girls) aged 7 to 11, enrolled in an after-school care center in Kimpo, Gyeonggi province. Most of their mothers had jobs(83.3%) and 75% were the beneficiaries of a government assistance program. When compared using body mass index(BMI) percentile, 16.7% of the subjects were classified as being overweight. The food intake patterns and meal qualities were evaluated from dietary records for three non-consecutive days. The mean dietary diversity score(DDS) was 3.8, suggesting at least one food group was deficit. Only 8.3% of the records indicated a satisfactory intake of all five food groups, and fruit was the most deficit food group(58.3%). Also, the proportion of balanced of meals was low, especially breakfast(36%), in that main dish(the source of protein) was not included. The children had problematic eating behaviors, such as an unbalanced diet, eating meals in a hurry, skipping breakfast, and irregular meal times. They answered that they liked to eat simple meals and convenient foods. In conclusion, nutrition education should incorporate strategies to reach families and help with meal planning and management, as well as modifying the eating behaviors of children, in order to improve nutritional status.