• Title/Summary/Keyword: random effect estimation

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Analysis of Periodicity of Meteorological Measures and Their Effects on Precipitation Observed with Surface Meteorological Instruments at Eight Southwestern Areas, Korea during 2004KOEP (기상인자의 주기성 분석 및 일반화 선형모형을 이용한 강수영향분석: 2004KEOP의 한반도 남서지방 8개 지역 기상관측자료사용)

  • Kim Hea-Jung;Yum Joonkeun;Lee Yung-Seop;Kim Young-Ah;Chung Hyo-Sang;Cho Chun-Ho
    • The Korean Journal of Applied Statistics
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    • v.18 no.2
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    • pp.281-296
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    • 2005
  • This article summarizes our research on estimation of area-specific and time-adjusted rainfall rates during 2004KEOP (Korea enhanced observation period: June 1, $2004{\sim}$ August 31, 2004). The rainfall rate is defined as the proportion of rainfall days per week and areas are consisting of Haenam, Yeosu, Janghung, Heuksando, Gwangju, Mokpo, Jindo, and Wando. Our objectives are to analyze periodicity in area-specific precipitation and the meteorological measures and investigate the relationships between the geographic pattern of the rainfall rates and the corresponding pattern in potential explanatory covariates such as temperature, wind, wind direction, pressure, and humidity. A generalized linear model is introduced to implement the objectives and the patterns are estimated by considering a set of rainfall rates produced using samples from the posterior distribution of the population rainfall rates.

Quantification of Reactor Safety Margins for Large Break LOCA with Application of Realistic Evaluation Methodology (최적평가 방법론의 적용에 의한 대형냉각재 상실사고시의 원자로 안전여유도의 정량화)

  • B.D. Chung;Lee, Y.J.;T.S. Hwang;Lee, W.J.;Lee, S.Y.
    • Nuclear Engineering and Technology
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    • v.26 no.3
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    • pp.355-366
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    • 1994
  • The USNRC issued a revised ECCS rule that allows the use of best estimate computer codes for safety analysis. The rule also requires an estimation of uncertainty in calculated system response when applying the best estimate computer codes. A practical realistic evaluation methodology to evaluate the ECCS performance that satisfies the requirements of the ECCS rule has been developed and this paper describes the application of new realistic evaluation methodology to large break LOCA for, the demonstration of the new methodology. The computer code RELAP5/MOD3/KAERI, which was improved from RELAP5/MOD3.1, was used as the best estimate code in the application. The uncertainty of the code was evaluated by assessing several separate and integral effect tests, and for the application to actual plant Kori 3 & 4 was selected as the reference plant. Response surfaces for blowdown and reflood PCTs were generated from the results of the sensitivity analyses and probability distribution functions were established by random sampling or Monte-Carlo method for each response surface. Final uncertainties were quantified at 95% probability level and safety margins for large break LOCA were discussed.

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Estimation of Carbon Stock in the Chir Pine (Pinus roxburghii Sarg.) Plantation Forest of Kathmandu Valley, Central Nepal

  • Sharma, Krishna Prasad;Bhatta, Suresh Prashad;Khatri, Ganga Bahadur;Pajiyar, Avinash;Joshi, Daya Krishna
    • Journal of Forest and Environmental Science
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    • v.36 no.1
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    • pp.37-46
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    • 2020
  • Vegetation carbon sequestration and regeneration are the two major parameters of forest research. In this study, we analyzed the vegetation carbon stock and regeneration of community-managed pine plantation of Kathmandu, central Nepal. Vegetation data were collected from 40 circular plots of 10 m radius (for the tree) and 1m radius (for seedling) applying a stratified random sampling and nested quadrat method. The carbon stock was estimated by Chave allometric model and estimated carbon stock was converted into CO2 equivalents. Density-diameter (d-d) curve was also prepared to check the regeneration status and stability of the plantation. A d-d curve indicates the good regeneration status of the forest with a stable population in each size class. Diversity of trees was very low, only two tree species Pinus roxburghii and Eucalyptus citriodora occurred in the sample plots. Pine was the dominant tree in terms of density, basal area, biomass, carbon stock and CO2 stock than the eucalyptus. The basal area, carbon stock and CO2 stock of forest was 33±1.0 ㎡ ha-1, 108±5.0 Mg ha-1 and 394±18 Mg ha-1, respectively. Seedling and tree density of the plantation was 4,965 ha-1 and 339 ha-1 respectively. The forest carbon stock showed a positive relationship with biomass, tree diameter, height and basal area but no relationship with tree density. Canopy cover and tree diameter have a negative effect on seedling density and regeneration. In conclusion, the community forest has a stable population in each size class, sequestering a significant amount of carbon and CO2 emitted from densely populated Kathmandu metro city as the forest biomass hence have a potentiality to mitigate the global climate change.

Some Results from a Sample Survey on the Use of Moxibustion Therapeutics in Korea (국내 뜸요법 사용실태에 관한 표본조사 결과)

  • Kim, Sun-Woong;Hong, Sung-Joon;Park, So-Hyung;Jung, Chan-Yung;Yoon, Eun-Hye;Lee, Seung-Deok
    • Journal of Acupuncture Research
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    • v.27 no.2
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    • pp.115-121
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    • 2010
  • Objectives : Based on a national sample survey, we present an analysis of the current situation in the use of moxibustion therapeutics by qualified medical practitioners in Korea. Methods : The survey population of 11,737 hospitals is stratified by administrative regions, and 331 of them are randomly selected from the list of hospitals. The same number of Korean medical doctors is interviewed under the computer-assisted telephone interviewing(CATI) system. The bound on the error of estimation is ${\pm}\;5.0%$ point. Results : Of the 331 Korean medical doctors surveyed, 69% have used moxibustion therapy for remedial treatment. About half of those doctors have employed the therapy for their patients over 30%. The average number of acupuncture points per treatment using the therapy mostly ranges 1 between 5. The percent of practitioners, who have the number of average minutes less than 20 in treatment, is 74%. The number of practitioners who primarily use modified moxibustion is 4 times as many as that of those using traditional moxibustion. Conclusions : Considering the survey results, if the laser heater, alternative to conventional moxibustion, which not only gives high thermal effect but also reduces both the users inconvenience and side effects, are developed, it may benefit more patients as well as Korean medical doctors.

A Study on the Reliability-Based Optimum Design of Reinforced Concrete Frames (철근(鐵筋)콘크리트 뼈대구조(構造) 신뢰성(信賴性) 최적설계(最適設計)에 관한 연구(硏究))

  • Kim, Kee Dae;Yang, Chang Hyun;Cho, Hyo Nam
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.9 no.3
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    • pp.57-64
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    • 1989
  • This study presents a reliability-based optimum design of reinforced concrete frames, in which the AFOSM and SOSM methods are applied for the evaluation of the failure probabilities, and the sequential linear programming method is used as a practical approach to the system optimization. One-story two-bay reinforced concrete frame is chosen for the numerical illustration of the proposed reliability-based optimum design. As a result, it is found that the proposed procedure for the reliability-based optimization of RC frames could provide the accurate estimation of the optimal level of safety, and appears applicable to real structures with reasonable complexity. It is shown in the paper that the probability distributions of the basic random variables and the uncertainties of the applied loadings and material strengths may have great effect on the optimum design, but the AFOSM and SOSM methods do not show significant discrepancy in the optimum design results, but the former appears more realistic and time saving than the latter for this specific study.

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Global prevalence of classic phenylketonuria based on Neonatal Screening Program Data: systematic review and meta-analysis

  • Shoraka, Hamid Reza;Haghdoost, Ali Akbar;Baneshi, Mohammad Reza;Bagherinezhad, Zohre;Zolala, Farzaneh
    • Clinical and Experimental Pediatrics
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    • v.63 no.2
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    • pp.34-43
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    • 2020
  • Phenylketonuria is a disease caused by congenital defects in phenylalanine metabolism that leads to irreversible nerve cell damage. However, its detection in the early days of life can reduce its severity. Thus, many countries have started disease screening programs for neonates. The present study aimed to determine the worldwide prevalence of classic phenylketonuria using the data of neonatal screening studies.The PubMed, Web of Sciences, Sciences Direct, ProQuest, and Scopus databases were searched for related articles. Article quality was evaluated using the Joanna Briggs Institute Critical Appraisal Evaluation Checklist. A random effect was used to calculate the pooled prevalence, and a phenylketonuria prevalence per 100,000 neonates was reported. A total of 53 studies with 119,152,905 participants conducted in 1964-2017 were included in this systematic review. The highest prevalence (38.13) was reported in Turkey, while the lowest (0.3) in Thailand. A total of 46 studies were entered into the meta-analysis for pooled prevalence estimation. The overall worldwide prevalence of the disease is 6.002 per 100,000 neonates (95% confidence interval, 5.07-6.93). The meta-regression test showed high heterogeneity in the worldwide disease prevalence (I2=99%). Heterogeneity in the worldwide prevalence of phenylketonuria is high, possibly due to differences in factors affecting the disease, such as consanguineous marriages and genetic reserves in different countries, study performance, diagnostic tests, cutoff points, and sample size.

Probabilistic Analysis of Repairing Cost Considering Random Variables of Durability Design Parameters for Chloride Attack (염해-내구성 설계 변수에 변동성에 따른 확률론적 보수비용 산정 분석)

  • Lee, Han-Seung;Kwon, Seung-Jun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.22 no.1
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    • pp.32-39
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    • 2018
  • Repairing timing and the extended service life with repairing are very important for cost estimation during operation. Conventionally used model for repair cost shows a step-shaped cost elevation without consideration of variability of extended service life due to repairing. In the work, RC(Reinforced Concrete) Column is considered for probabilistic evaluation of repairing number and cost. Two mix proportions are prepared and chloride behavior is evaluated with quantitative exterior conditions. The repairing frequency and cost are investigated with varying service life and the extended service life with repairing which were derived from the chloride behavior analysis. The effect of COV(Coefficient of Variation) on repairing frequency is small but the 1st repairing timing is shown to be major parameter. The probabilistic model for repairing cost is capable of reducing the number of repairing with changing the intended service life unlike deterministic model of repairing cost since it can provide continuous repair cost with time.

The Effect of Job Stress and Turnover Intention among the Employee of Private Security (민간경비원의 직무스트레스가 이직의사에 미치는 영향)

  • Park, Young-Jin;Ahn, Hwang-Kwon;Wang, Sug-Won
    • Korean Security Journal
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    • no.12
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    • pp.177-200
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    • 2006
  • This research result that analysis as following. First, difference that keep in mind partially as result that verify difference of job-stress by demography special qualitys that is common people guard's society and turnover intention appeared. Second, result that analyze relation with job-stress and turnover intention, displayed statical correlation in job environment. Third, result that keep in mind as statistical as result that verify effect that common people guard's job-stress gets to turnover intention appeared. During is job-stress variable, was expose that exert effect that keep in mind to turnover intention job surrounding and job special quality. Suggestion point through this research as following be. To raise common people guard's job-stress and turnover intention. system improvement strategy about social estimation etc.. is effective, and do on the basis of this and may have to establish common people guard's enhancing morale plan strategy, low complement that can exert negative impact in change of post for example, line of duty that it is seldom competence, daytime that can elicit common people guards' job satisfaction. Is in visual point that activation of continuous research is leaned against by depth interview and review through qualitative research was insufficient relatively in virtue research so far in research after.

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Analysis of the ODA impact that Donor's Exports - Focus on Korean Technology Cooperation ODA (ODA가 공여국의 수출에 미치는 영향 분석 - 한국의 기술협력 ODA를 중심으로)

  • Byun, Sejun;Choi, Jaeyoung
    • Journal of Technology Innovation
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    • v.27 no.2
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    • pp.99-122
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    • 2019
  • ODA (Official Development Assistance) aims for practicing international humanitarianism in developing countries. However, ODA donors also seek to find convincing evidence meeting the national economic & political interests in the international community. In this regards, precise & unbiased estimation of the policy effects of ODA aid on the donors' exports to the recipient countries has recently become one of the primary concerns of the ODA donors, especially developing countries including Korea of which economy structure heavily relies on exports for economic growth. Based on the basic gravity model, this study empirically analyzes the effects of technical cooperation ODA delivering skills, knowledge and technical know-how on Korea's exports to the ODA recipient countries using 10-year panel data from 2007 to 2016. Specifically, by incorporating major variables affecting trade such as GDP, distance, FDI etc, the effect of technical cooperation ODA on Korea's exports to the ODA recipient countries is estimated with various kinds of panel models. As a result, technical cooperation ODA has a statistically significant impact on Korea's exports to ODA recipient countries, especially in the exports of intermediate goods. And the detail process of this black-boxed mechanism is scrutinized through case studies on Uzbekistan, The Philippines, and Morocco.

The Study about the Effect on Self-effectiveness of a Course Decision of Duty Stress in the College Students Related to Guard Major Study - Centering Around Gwang-ju and Jeonnam Region - (경호관련 전공 대학생들의 취업스트레스와 진로결정 자기 효능감에 관한 연구)

  • Kim, Pyong-Soo;Kim, Kong;Seo, Seok-Yun;Kim, Yeong-Nam
    • Korean Security Journal
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    • no.31
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    • pp.47-71
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    • 2012
  • This study is to analyse the effect on self-effectiveness of a course decision of duty stress in the college students related to guard major study. For this, the college students related to guard major study in Gwang-ju and Jeonnam region were selected as a universe at April 2011. And a sampling was practiced as a random sample. A question investigation was used in a entry method of self-estimation. Furthermore a total of 171 person(85.5%) was used as final analysis data. The collected data were employed in a statistics program of SPSS for win version 17.0. And used in a way of Pearson's interrelation analysis and Multiple Regression Analysis. The conclusion was as follows. Firstly, family surroundings stress and studies stress of duty stress affected beneficially statistically a goal selection of self-effectiveness of course decision. Family surroundings influenced upon it positively. And studies effected on it negatively. Secondly, all factors of duty stress didn't affect beneficially statistically the work information of self-effectiveness of course decision. Thirdly, school surroundings stress of duty stress influenced upon positively statistically the problem solution of self-effectiveness of course decision. Fourthly, personality stress and duty anxiety stress affected beneficially statistically the future plan of self-effectiveness of course decision. Personality influenced upon it negatively and duty anxiety affected it positively.

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