• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.4
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• pp.328-337
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• 2021

Air pollution, which is a class 1 carcinogen, such as asbestos and benzene, is the cause of various diseases. The spread of ultra-air pollution is one of the important causes of the spread of the corona virus. This paper analyzes and predicts fine dust and ultra-air pollution from 2015 to 2019 based on weather data such as average temperature, precipitation, and average wind speed in Seoul and atmospheric environment data such as SO2, NO2, and O3. Linear regression, SVM, and ensemble models among machine learning models were compared and analyzed to predict fine dust by grasping and analyzing the status of air pollution and ultra-air pollution by season and month. In addition, important features(attributes) that affect the generation of fine dust and ultra-air pollution are identified. The highest ultra-air pollution was found in March, and the lowest ultra-air pollution was observed from August to September. In the case of meteorological data, the data that has the most influence on ultra-air pollution is average temperature, and in the case of meteorological data and atmospheric environment data, NO2 has the greatest effect on ultra-air pollution generation.

• Analytical Science and Technology
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• v.22 no.5
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• pp.369-375
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• 2009

We evaluated the homogeneity and accuracy of low level airborne fibrous standard, and accomplished the proper proficiency test. We had found that the correlation of concentration of standard solution and asbestos density was 0.9863~0.9968, and concluded that the proper guideline of the analysis result was ${\mid}Z{\mid}{\leq}2$ interval of Z-score.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3177-3183
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• 2013

This paper deals with the robust design of the non-asbestos FCM(Fiber-elastomer Coated Metal) gasket. In order to this, the measurement of the shear stress based on the design of experimet using the orthogonal table was carried out and the control factors for shear stress using the larger-the-better SN ratios with the Taguchi method were evaluated. In addition, the analysis of variance for SN ratios was conducted. The temperature, pressure, duration time and humidity were selected as the control factors. The orthogonal table $L_9(3^4)$ was made of 3 levels for each factor and the measurement of shear stress was acomplished on the base of the table. Delta statistics of time is the highest value 0.93 and therefore the time affect the largest effect on the shear stress of gasket. Also from the analysis, the shear stress shows maximun at the duration time 80 sec, temperature $200^{\circ}C$, pressure 90 $kgf/cm^2$, humidity 60 %RH. P values of duration time and temperature as a results of the analysis of variance are 0.037 and 0.098. Therefore the analysis has significant each with 95% and 90% confidence level.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.103-109
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• 2013

Background: The objective of this study is to determine knowledge about lung cancer among secondary school male teachers in Kudat, Sabah, Malaysia. Materials and Methods: A cross-sectional study was conducted among three secondary schools located in Kudat district, Sabah, Malaysia during the period from June until September 2012. The protocol of this study was approved by ethics committee of Management and Science University, Malaysia. The aims were explained and a consent form was signed by each participant. Respondents were chosen randomly from each school with the help of the headmasters. Self-administrated questionnaires, covering socio-demographic characteristics and general knowledge of lung cancer, were distributed. Once all 150 respondents completed the questionnaire, they passed it to their head master for collecting and recording. All the data were analyzed using Statistical Package for the Social Sciences (SPSS) version 13. ANOVA and t-test were applied for univariate analysis; and multiple linear regression for multivariate analysis. Results: A total of 150 male secondary school teachers participated in this study. Their mean age was $35.6{\pm}6.5$ (SD); maximum 50 and minimum 23 years old. More than half of the participants were Malay and married (52%, 79%; respectively). Regarding the knowledge about lung cancer, 57.3% of the participants mentioned that only males are affected by lung cancer. Some 70.7% mentioned that lung cancer can be transmitted from one person to another. More than half (56.7%) reported that lung cancer is not the leading cause of death in Malaysian males. As for risk factors, the majority reported that family history of lung cancer is not involved. However, 91.3% were aware that cigarettes are the main risk factor of lung cancer and more than half (52%) believed that second-hand smoking is one of the risk factor of lung cancer. More than half (51.3%) were not aware that asbestos, ionizing radiation and other cancer causing substances are risk factors for lung cancer. Quitting smoking, avoiding second-hand smoking and avoiding unnecessary x-ray image of the chest (53.3%, 96.0%, 87.3%; respectively) are the main preventive measures mentioned by the participants. For the factors that influence the participants knowledge, univariate and multivariate analysis showed that only race was significant. Conclusions: Overall, the knowledge of school male teachers about lung cancer was low. However, few items were scored high: cigarettes are the main risk factor; avoiding second-hand smoking; and avoiding x-rays. Interventions to increase lung cancer awareness are needed to improve early detection behavior. Increase the price of pack of cigarettes to RM 20 and banning smoking in public places such as restaurants are highly recommended as primary preventive measures.

• Journal of the Korean earth science society
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• v.33 no.1
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• pp.39-48
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• 2012

In this study, a statistical estimation of probable precipitation and an analysis of its return period in Busan were performed using long-term precipitation data (1973-2007) collected from the Busan Regional Meteorological Administration. These analyses were based on the method of probability weighted moments for parameter estimation, the goodness-of-fit test of chi-square ($x^2$) and the probability plot correlation coefficient (PPCC), and the generalized logistics (GLO) for optimum probability distribution. Moreover, the spatial distributions with the determination of probable precipitation were also investigated using precipitation data observed at 15 Automatic Weather Stations (AWS) in the target area. The return periods for the probable precipitation of 245.2 and 280.6 mm/6 hr with GLO distributions in Busan were estimated to be about 100 and 200 years, respectively. In addition, the high probable precipitation for 1-, 3-, 6-, and 12-hour durations was mostly distributed around Dongrae-gu site, all coastal sites in Busan, Busanjin and Yangsan sites, and the southeastern coastal and Ungsang sites, respectively.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.104-114
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• 2000

This study was carried out to estimate current status of dust concentrations in the factories producing non-metallic products in Korea. Data were gathered from the environmental monitoring reports by 40 workplace environmental monitoring institutes and the questionnaire designed for the study by the authors. A total of 1838 dust samples from 368 plants were obtained from the reports and were analyzed with no data modifications. But data on asbestos, rock wool, and welding fumes were excluded in this evaluation. The factories were classified into eight groups according to the standard industrial classification scheme in Korea. The results of this study were as follows; 1. The factories included were glass, non-refractory ceramic, refractory ceramic ware, structural non-refractory clay and ceramic, cement and lime, articles of concretes, and stone. Mean(geometric mean) concentrations of total dust samples ranged from $1.75(0.84)mg/m^3$ to $5.87(2.84)mg/m^3$. Statistically significantly higher dust concentrations were found in the cement and lime industries compared with other industries. 2. The non-compliance rates were 15.2% in glass and 20.6% in other non-metallic mineral products industries. Although all institutions surveyed utilized the identical sampling and classification scheme for dusts as specified in the current occupational exposure limits, wide discrepancies were found in collecting samples and classifying dusts. Further problems were discovered in classifying dusts. A dust sample collected could be classified into any of the three groups regardless of silica content. The results of this study showed that dust concentrations in the non-metallic products industries varied widely. Also discovered was classification errors of dust types among workplace monitoring institutes. These errors could adversely affect the results of exposure assessments and the true nature of dust hazards. Further, no institutions performed respirable dust sampling and analysis of crystalline silica. In order to correct these malpractices, current standards of occupational exposure limits should be revised and tight supervision by the Ministry of Labour be suggested.

• Tuberculosis and Respiratory Diseases
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• v.72 no.3
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• pp.302-309
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• 2012

Background: Korean regression models for spirometric reference values are different from those of Americans. Using spirometry results of Korean adults, goodness-of-fits of the Korean and the USA Caucasian regression models for forced vital capacity (FVC) and forced expiratory volume in one second ($FEV_1$) were compared. Methods: The number of study participants was 2,360 (1,124 males and 1,236 females). Spirometry was performed under the guidelines of the American Thoracic Society and the European Respiratory Society. After excluding unsuitable participants, spirometric data for 729 individuals (105 males and 624 females) was included in the statistical analysis. The estimated FVC and $FEV_1$ values were compared with those measured. Goodness-of-fits for Korean and USA Caucasian models were compared using an F-test. Results: In males, the expected values of FVC and $FEV_1$ using the Korean model were 12.5% and 5.7% greater than those measured, respectively. The corresponding values for the USA Caucasian model were 3.5% and 0.6%. In females, the difference in FVC and $FEV_1$ were 13.5% and 7.7% for the Korean model, and 6.3% and 0.4% for the USA model, respectively. Goodness-of-fit for the Korean model regarding FVC was not good to the study population, but the Korean regression model for $FEV_1$, and the USA Caucasian models for FVC and $FEV_1$ showed good fits to the measured data. Conclusion: These results suggest that the USA Caucasian model correlates better to the measured data than the Korean model. Using reference values derived from the Korean model can lead to an overestimation regarding the prevalence of abnormal lung function.

• Journal of Life Science
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• v.21 no.4
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• pp.549-553
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• 2011

This study was performed to determine whether or not urinary 1-hydroxypyrene (1-OHP) levels can be accurately detected by our 1-OHP-detecting $TiO_2$-Bead-HPLC assay that we developed based on the molecular imprinting method. Our method showed a variation coefficient of 4.97% and a between-day variation coefficient of 4.43%, suggesting that this may be a very stable method. In addition, the recovery rate of 1-OHP from a mixture of 1-OHP and similar substances using our $TiO_2$-Bead-HPLC method was estimated to be 105.6%. The correlation coefficient between the conventional enzyme-HPLC method and this new method was 0.74 (p<0.01) when the urine samples were tested. Based on this result, it is conceivable that our method could be a useful technique for measuring urinary 1-OHP levels. Moreover, our method has some advantages of being easier and less expensive than the conventional method. The results of this study suggest that our method can facilitate the development of a urine 1-OHP sensor using $TiO_2$-coating beads and that development of beads by molecular imprinting can be applied to analysis of chemicals other than 1-OHP.