• Economic and Environmental Geology
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• v.27 no.1
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• pp.1-9
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• 1994

The Kyungju pyrophyllite deposits were formed by the hydrothermal alteration of andesitic rocks, which were intruded by Cretaceous granite mass. The major minerals are pyrophyllite, kaolinite and chlorite. The deposits may be zoned outward into pyrophyllite zone, silicified pyrophyllite zone and weakly altered zone (propyrilite zone) according to mineral assemblages. Chemical compositions vary in close relation with the mineralogical assemblages: $Al_2O_3$ content is high due to pyrophyllitization at the deposits and altered zones in comparison to andesitic country rocks, while the contents of $Na_2O$, CaO and MgO are generally low due to leaching during the alteration. This variation of chemical elements may be applicable in the geochemical exploration of pyrophyllite deposits.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.81-84
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• 2006

Currently, natural aggregates of good quality are hard to use because of continuous decrease of internal aggregate resource and regulation of gathering. So, use of crushed sand was being increased. On the other hand, skyscraper projects with 100 stories are being planned within the country and high strength concrete must be used to construct a skyscraper with 100 stories. High strength concrete is necessary to use crushed sand too because we are still unable to secure natural aggregates of good quality. So, This study indicated basic data necessary for mix design of high strength concrete through valuation of concrete property by quality variation of crushed sand.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.2
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• pp.139-150
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• 1999

The ozone concentrations measured at the National Air Monitoring Stations between 1990 and 1995 were reviewed to detect any anomalies in the measurements. By screening the cases, in which variation of the ozone concentration from the previous measured value is greater than 75ppb, 125 station-days were identified as the test cases for the anomaly test. Historical and parallel consistencies of the measured concentrations were examined by plotting data for each test case. The detected anomalies can be classified into four categories; single outliers, anomalous variations during the startup period, baseline rises, and fluctuations in th diurnal variations. Anomalies were detected in as many as 80 cases among 125 test cases. Because of these anomalies, the number of hours exceeding 100ppb in the areas other than the Greater Seoul Area(GSA) could decrease from 157 to 107. Further studies for developing the methodology for eliminating the abnormal monitoring data are warranted for the data from the National Air Monitoring Stations are official to the both inside and outside of the country.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.2
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• pp.76-93
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• 1997

Activated carbon is widely used for the treatment of water, wastewater and other liquid wastes. Biological activated carbon (BAC) process is water and wastewater treatment process developed in the 1970's. In addition to activated carbon adsorption, biodegradation organic pollutants occurs in the BAC bed where a large amount of aerobic biomass grows. This results in a long operation time of the carbon before having to be regenerated and thus a low treatment cost. Although the BAC process has been widely used, its mechanisms have not been well understood, especially the relationship between biodegradation and carbon adsorption, whether these two reactions can promote each other or whether they just simultaneously exist in the BAC bed. Also, the phenomenon of bioregeneration has been confused that previously occupied adsorption sites appear to be made available through the actions of microorganisms. And that, because biological process is influenced by low temperature, the mechanism of the BAC process is also effected by temperature variation in our country of winter temperature near the freezing point. Therefore, the objective of this study examines closely the mechanism of the BAC process by temperature variation using phenol as substrate. From this study, biological activated carbon is good substrate removal better than non adsorbing materials (charcoal, sand) as temperature variation, especially low temperature(near $5^{\circ}C$).

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.446-451
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• 2008

Air washer remove dust on the air and use for humidification. But the last should be applied to the semiconductor and FPD industry, air washer has focused on removing pollutants. In addition, air washer within the clean room remove the pollutants as well as use for humidification in Winter. However, there is no research in the country, and for research purposes, the evaluation was conducted by atomizing water temperature variation and L/G variation. Performance evaluation results are the same conditions as the entrance of air washers ($23^{\circ}C$, 45%RH). Cooling effect is enhanced when atomizing water temperature is lower. The larger the performance of humidification to L/G lower the temperature increases.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4661-4664
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• 2016

Background: Artificial light at night (ALAN) has been linked to increased risk of cancers in body sites like the breast and colorectum. However exposure of ALAN as an environmental risk factor and its relation to cancers in humans has never been studied in detail. Objective: To explore the association of ALAN with all forms of cancers in 158 countries. Materials and Methods: An ecological study encompassing global data was conducted from January to June 2015, with age-standardized rates (ASR) of cancers as the outcome measure. ALAN, in the protected areas, as the exposure variable, was measured with reference to the Protected Area Light Pollution Indicator (PALI) and the Protected Area Human Influence Indicator (PAHI). Pearson's correlations were calculated for PALI and PAHI with ASR of cancers for 158 countries, adjusted for country populations, electricity consumption, air pollution, and total area covered by forest. Stratified analysis was conducted according to the country income levels. Linear regression was applied to measure the variation in cancers explained by PALI and PAHI. Results: PALI and PAHI were positively associated with ASR of all forms of cancer, and also the four most common cancers (p < 0.05). These positive correlations remained statistically significant for PAHI with all forms of cancer, lung, breast, and colorectal cancer after adjusting for confounders. Positive associations of PALI and PAHI with cancers varied with income level of the individual countries. Variation in all forms of cancers, and the four most common cancers explained by PALI and PAHI, ranged from 3.3 - 35.5%. Conclusion: Artificial light at night is significantly correlated for all forms of cancer as well as lung, breast, colorectal, and prostate cancers individually. Immediate measures should be taken to limit artificial light at night in the main cities around the world and also inside houses.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6795-6798
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• 2015

Breast cancer incidence and mortality in Kazakhstan are considered to be increasing but exact statistics have hitherto been lacking. The present study was therefore undertaken to retrospectively assess data for the whole country, accessed from the central registration office, for the period 1999-2013. Age standardized data for incidence and mortality were generated and compared across age groups. It was determined that during the studied period 45,891 new cases of breast cancer were registered and 20,122 women died of this pathology. Average breast cancer incidence and mortality were $37.9{\pm}1.10/10^5$ and $16.7{\pm}0.20/10^5$ respectively, and the overall ratio of mortality/incidence (M/I) was 0.44. Incidence tended to increase (T = + 2.3%), and mortality to decrease (T of =-0.3%). Peaks of incidence and mortality were noted in those aged 60-74 years and 75-84, respectively. Particularly high incidences were established in large cities of Kazakhstan, Astana ($46.8{\pm}1.80/10^5$) and Almaty ($49.7{\pm}1.30/10^5$), and high mortality was observed in the Pavlodar region ($17.9{\pm}0.60/10^5$) and Almaty city ($20.1{\pm}0.40/10^5$). Considerable variation in the mortality/incidence ratio was noted, suggesting the need for more stress on access to screening and clinical care in some regions of the country.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.27-32
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• 2016

Stomach cancer, the fourth most common cancer and the second leading cause of cancer-related death through the world, is very common in parts of Iran. Geographic variation in the incidence of stomach cancer is due to many different factors. The aim of this study was to assess the geographical and spatial distribution of stomach cancer in Iran using data from the cancer registry program in Iran for the year 2009. The reported incidences of stomach cancer for different provinces were standardized to the world population structure. ArcGIS software was used to analyse the data. Hot spots and high risk areas were determined using spatial analysis (Getis-Ord Gi). Hot and cold spots were determined as more than or less than 2 standard deviations from the national average, respectively. A significance level of 0.10 was used for statistical judgment. In 2009, a total of 6,886 cases of stomach cancers were reported of which 4,891 were in men and 1,995 in women (standardized incidence rates of 19.2 and 10.0, respectively, per 100,000 population). The results showed that stomach cancer was concentrated mainly in northwest of the country in both men and women. In women, northwest provinces such as Ardebil, East Azerbaijan, West Azerbaijan, Gilan, and Qazvin were identified as hot spots (p<0.1). In men, all northwest provinces, Ardabil, East Azerbaijan, Gilan, Qazvin, Zanjan and Kurdistan, the incidences were higher than the national average and these were identified as hot spots (P<0.01). As stomach cancer is clustered in the northwest of the country, further epidemiological studies are needed to identify factors contributing to this concentration.

• Water for future
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• v.28 no.2
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• pp.103-114
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• 1995

A stochastic model "STO-RIV" for the prediction of water quality variation in a river system has been developed. Extended Streeter-Phelps equation and Monte Carlo simulation are used in the model. The model is applied to the reach of Waegwan to Mulkeum in the Nakdong River to compute the probability distribution of BOD and DO concentration at Mulkeum site. As the strategies to attain the goal of the water quality, some alternatives considering the treatment effect of the Keumho river are discussed using the stochastic model. Application of stochastic analysis to water quality management is strongly recommended in this country.s country.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7235-7239
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• 2014

Cervical cancer, the third commonest cancer in women worldwide, can be prevented through early detection by cervical screening (Pap smear). The aim of this study was to investigate the attitudes and practice of cervical cancer screening among female undergraduate university students from 25 low, middle income and emerging economy countries. Using anonymous questionnaires, data were collected from 9,194 female undergraduate university students aged 18-26 years (mean age 20.9, SD=2.0) from 26 universities in 25 countries across Asia, Africa and the Americas. Overall, 11.6% of the female students indicated that they had conducted one or more times a cervical (Pap) smear test; 8.3% among 18-20 year-olds and 15.6% among 21-26 year-old students. There was considerable country variation on having had a cervical (Pap) smear test among 21-26 year-old female university students, ranging from 59.2% in Colombia and 50.9% in Barbados to 0% in India and 1.0% in Tunesia. Logistic regression showed that cervical cancer screening importance or positive attitude were highly associated with the cervical screening practice. Moreover, risky sexual behaviour and tobacco use, two cervical cancer risk factors, were associated with screening. Cervical cancer screening practices were found to be inadequate and e fforts should be made to develop programmes that can increase the uptake of cervical cancer screening.