• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2006년도 춘계학술대회
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• pp.319-324
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• 2006

In this paper, we propose Bayesian procedure for the multiple change points analysis in a sequence of fractions nonconforming. We first compute the Bayes factor for detecting the existence of no change, a single change or multiple changes. The Gibbs sampler with the Metropolis-Hastings subchain is run to estimate parameters of the change point model, once the number of change points is identified. Finally, we apply the results developed in this paper to both a real and simulated data.

• Bulletin of the Korean Chemical Society
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• 제21권7호
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• pp.697-700
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• 2000

A method of calculating the excess Helmholtz free energy from the average of the bent effective acceptance ratio for two-center-Lennard-Jones liquids has been presented. The bent effective acceptance ratio has been newly composed from the acceptan ce ratio for the potential energy difference between a configuration in the Metropolis Monte Carlo procedure and random virtual configuration generated by the separate parallel Monte Carlo procedure and the Boltzmann factor for half the potential energy difference. The excess Helmholtz free energy was calculated directly from the average of the bent effective acceptance ratio through a single Metropolis Monte Carlo run. Because the separate parallel Monte Carlo procedure was used, this method can be applied to molecular dynamics simulations. For two-center-Lennard-Jones liquids, the average of the bent effective acceptance ratio gave better results than use of the modified effective acceptance ratio in the previous work.

• Structural Engineering and Mechanics
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• 제71권4호
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• pp.329-339
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• 2019

Assessment of failure probability, especially for a complex structure, requires a considerable number of calls to the numerical model. Reliability methods have been developed to decrease the computational time. In this approach, the original numerical model is replaced by a surrogate model which is usually explicit and much faster to evaluate. The current paper proposed an efficient reliability method based on Monte Carlo simulation (MCS) and multi-gene genetic programming (MGGP) as a robust variant of genetic programming (GP). GP has been applied in different fields; however, its application to structural reliability has not been tested. The current study investigated the performance of MGGP as a surrogate model in structural reliability problems and compares it with other surrogate models. An adaptive Metropolis algorithm is utilized to obtain the training data with which to build the MGGP model. The failure probability is estimated by combining MCS and MGGP. The efficiency and accuracy of the proposed method were investigated with the help of five numerical examples.

• 복식문화학회:학술대회논문집
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• 복식문화학회 1998년도 International Costume Culture Conference
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• pp.17-17
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• 1998

• 정보처리학회논문지B
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• 제14B권7호
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• pp.541-548
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• 2007

모의 담금질 방법은 널리 사용되는 최적화 알고리즘들 중의 하나로서, 그 해의 수렴성이 수학적으로 증명되어 있는 장점이 있다. 하지만 원래의 모의 담금질 방법은 수렴 속도가 매우 느리기 때문에 복잡한 문제에 적용하기 힘들고, 이를 해결하기 위해서 빠른 모의 담금질 방법과 같은 다양한 방법이 연구되고 있다. 본 논문에서는, greedy 선택방법을 적용한 모의 담금질 방법을 제안하고, 이 알고리즘이 연속적인 공간에서의 최적화 문제에 대해서 전역 최적점을 찾아낸다는 것을 확률적으로 증명한다. greedy 선택방법은 무조건 좋은 해를 선택하기 때문에, 확률적으로 좋지 않은 해를 선택할 가능성이 있는 Metropolis 선택방법에 비해 빠른 수렴속도를 얻을 수 있다. 컴퓨터 모의 실험 결과, greedy 선택방법을 사용한 모의 담금질 방법이 기존의 빠른 모의 담금질 방법과 비슷한 성능을 보이는 해를 더 빠른 속도로 찾을 수 있음을 보인다. 또한, greedy 선택방법에서는 선택 가능한 상태들의 비용함수 값의 우열관계만을 이용하여 선택하기 때문에 비용 함수의 크기 조정에 무관하게 적용할 수 있다는 장점이 있다.

• Safety and Health at Work
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• 제7권3호
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• pp.218-224
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• 2016

Background: Butchering is often associated with high rates of work-related musculoskeletal disorders (WRMSDs). However, published work on the prevalence of WRMSDs among butchers in Nigeria is scarce. This is important because meat processing practices differ across geographical and cultural locations. This study was therefore aimed at analyzing WRMSDs among butchers in Kano metropolis. Methods: Sociodemographic and work-settings information was obtained from 102 male cattle butchers (age, $37.49{\pm}11.68years$) through survey. Information on the prevalence and pattern of musculoskeletal disorders was obtained from the respondents using the Standardized Nordic Questionnaire. Additional information on health seeking practices was also obtained using a pro forma. Associations between the prevalence of WRMSDs and each of the sociodemographic data and work settings were explored using Chi-square analysis. The level of significance was set at p < 0.05. Results: The 12-month and point prevalence rates of WRMSDs among butchers in this study were 88.2% and 74.5%, respectively. Whereas lower back complaints (66.7%) were the overall and lower body quadrant's most commonly reported WRMSDs among the butchers surveyed, wrist/hand complaints were the leading upper quadrant's (45.1%) most commonly reported WRMSDs among the respondents. There were significant associations between age and majority of WRMSDs in the body regions. Only 23.3% of the 90 individuals who had WRMSD visited the hospital to seek redress for their WRMSD. Conclusion: The prevalence of WRMSDs is high among butchers in Kano Metropolis. Few individuals with WRMSD utilize healthcare facilities. Age is a major risk factor in this setting.

• 한국지역지리학회지
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• 제13권3호
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• pp.235-253
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• 2007

본 연구에서는 우리나라 7대 대도시를 대상으로 지속가능발전성을 비교 평가하였다. 국가지속가능발전지표 목록 등을 참고하여 3개 부문, 14개 지표군, 42개 하위지표를 선정하여 정량적 지표체계를 구축하였다. 대도시간 비교분석을 위해 지표별로 7대 대도시의 평균값을 기준으로 지속가능성을 상대평가 하였으며, 이 때 필요시 역기능지표를 순기능 지표화 하여 모든 지표를 동일한 스케일로 비교 가능하도록 하였다. 그 결과 서울이나 울산과 같이 특정산업이 집중한 도시에서 경제적 지속가능성이 높았으나 환경적 지속가능성은 낮았고, 지역경제가 낙후된 광주에서 환경적 지속가능성이 높은 것으로 나타났다. 부산, 대구, 인천은 전반적으로 지속가능성이 낮은 반면, 대전은 3개 부문 모두에서 조화롭게 지속가능성이 높아 대도시 중 통합적 지속가능성이 제일 높은 것으로 나타났다.

• Safety and Health at Work
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• 제10권1호
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• pp.47-53
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• 2019

Background: Despite growing concern over occupational exposure to particulate matter (PM) such as grain dust and diesel exhaust, information about the exposure level and health implications among workers in small-scale milling enterprises in developing countries like Nigeria has not been adequately documented. The purpose of this study was to assess the level of exposure to grain dust and diesel exhaust and effect on lung function among grain millers in food markets in Ibadan metropolis, Nigeria. Methods: The study adopted descriptive cross-sectional design with a comparative approach. Sixteen grain milling shops each were randomly selected from two major food markets in Ibadan metropolis for indoor $PM_{10}$ and $PM_{2.5}$ monitoring. Seventy-two respondents each were proportionately selected from grain millers and shop owners for forced expiratory volume in one second and peak expiratory flow rate tests. Results: The $PM_{2.5}$ concentrations for both market locations ranged between 1,269.3 and $651.7{\mu}g/m^3$, while $PM_{10}$ concentrations were between 1,048.2 and $818.1{\mu}g/m^3$. The recorded concentrations exceeded the World Health Organization guideline limit of $50{\mu}g/m^3$ and $25{\mu}g/m^3$ for $PM_{2.5}$ and $PM_{10}$, respectively. As compared with control group (2.1 L), significantly lower forced expiratory volume in one second value (1.61 L) was observed among the exposed group (p < 0.05). Likewise, significantly lower peak expiratory flow rate value (186.7 L/min) was recorded among the exposed group than the control group (269.51 L/min) (p < 0.05). Conclusion: Exposure to grain dust and diesel exhaust accentuated respiratory disorders with declines in lung functions amongst grain millers. Improved milling practices and engaging cleaner milling facilities should be adopted to minimize exposure and related hazards.

• Communications for Statistical Applications and Methods
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• 제4권1호
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• pp.259-269
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• 1997

Bayesian inference for a record value statistics(RVS) model of nonhomogeneous Poisson process is considered. We seal with Bayesian inference for double exponential, Gamma, Rayleigh, Gumble RVS models using Gibbs sampling and Metropolis algorithm and also explore Bayesian computation and model selection.

• 한국치위생학회지
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• 제10권4호
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• pp.607-616
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• 2010

Objectives : This study was performed to enhance a rate of Using oral clinic and to search related factors of using oral clinics. Methods : The subjects of the study were 74,698 subjects who answered to the 2007 korea Youth Risk Behavior Web-based survey. Answers of 73,836 subjects were used for the final analysis. We used spss of version 12.0. This study conducted a Chi-square test to identify using oral clinics rate according to characteristics of subjects and a multivariate logistic regression analysis to identify whether they are independently significant. Results : Tooth scaling experiences were responded by 10,060 subjects(25.6%). Grade and metropolis, economic level had significant associations with using oral clinic experiences. The rate of using oral clinic showed significant difference in point, depending on general characteristics. Their oral health showed significant difference in point between using oral clinic experience and non-experience groups. According to the multiple logistics regression analysis whose significant independent variables were sex, grade, metropolis, economic level, blooding gum, tooth brushing, oral malodor. Conclusions : The policy is needed to prevent economic constraints from worsening oral health by supporting the poor. And our government should eventually prepare a public relation program suitable for public.