• Korean Journal of Community Nutrition
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• v.4 no.1
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• pp.95-102
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• 1999

This study used questionnaires to investigate the safety awareness for imported foods by 365 male and female adults in Taejon. The results of the study were as follow : By factor analysis, the subjects' behaviors and awareness of the imported food was grouped into 3 factors such as 'health and quality factor', 'purchasing factor' and 'contamination factor'. 'Health and quality factor' and 'purchasing factor' were not recognized negatively by the subjects, moreover' contamination factor' was recognized very highly. The subjects' concern and worry about the imported food was also very high. The marital status, education level, nutriton knowledge adn recognition level of contamination by pesticides and heavy metals of foods partially affected the recognitio level of imported foods. The major selection criteria of imported food were distribution period(36.3%), price(28.8%) and purchasing experience(17.3%). The imported food mean discrimination score was 8.4±3.1 out of 13. The worst discriminatio score was red pepper. The subjects' experiences with imported foods selection affected the most instead of education level or nutrition knowledge. The higher discrimination score group more negatively recognized imported food and contamination recognition level was higher whereas the lowerdiscrimination score group more positively recognized the purchasing frequency and with to buy more easily. But both groups desired to reinforce contamination control. The better discrimination score of imported food pooring recognized sanitation concerns(p<0.05), quality(p<0.05), cooking convenience(p<0.01), desire for more variety(p<0.05), and the higher contamination recognition level(p<0.05) and desire to reinforce contamination control(p<0.01).

• Environmental Analysis Health and Toxicology
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• v.31
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• pp.6.1-6.10
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• 2016

Objectives This study examined the spatial distribution and the extent of soil contamination by heavy metals resulting from primitive, unconventional informal electronic waste recycling in the Agbogbloshie e-waste processing site (AEPS) in Ghana. Methods A total of 132 samples were collected at 100 m intervals, with a handheld global position system used in taking the location data of the soil sample points. Observing all procedural and quality assurance measures, the samples were analyzed for barium (Ba), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn), using X-ray fluorescence. Using environmental risk indices of contamination factor and degree of contamination ($C_{deg}$), we analyzed the individual contribution of each heavy metal contamination and the overall $C_{deg}$. We further used geostatistical techniques of spatial autocorrelation and variability to examine spatial distribution and extent of heavy metal contamination. Results Results from soil analysis showed that heavy metal concentrations were significantly higher than the Canadian Environmental Protection Agency and Dutch environmental standards. In an increasing order, Pb>Cd>Hg>Cu>Zn>Cr>Co>Ba>Ni contributed significantly to the overall $C_{deg}$. Contamination was highest in the main working areas of burning and dismantling sites, indicating the influence of recycling activities. Geostatistical analysis also revealed that heavy metal contamination spreads beyond the main working areas to residential, recreational, farming, and commercial areas. Conclusions Our results show that the studied heavy metals are ubiquitous within AEPS and the significantly high concentration of these metals reflect the contamination factor and $C_{deg}$, indicating soil contamination in AEPS with the nine heavy metals studied.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.440-443
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• 2003

Recently, with the rapid growth of industry, environmental condition became worse. With the mix of the various contaminants, such as, salts, dust and industrial pollutants, synergy effect could be happened. So, many researches have been focused on the issue. The cause of natural accident could be classified as, lightning, rainstorm and contamination. However, the accident by contamination influences on the larger area than that by lightning, and, in the case of rapid contamination, it takes a shorter time than rainstorm. The salt contaminant is one of the most representative pollutants, and known as the main source of the accident by contamination. So, in this investigation we make a research on the prediction of contamination degree through the relationship analysis between the climatic factor and ESDD.

• Journal of Industrial Technology
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• v.18
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• pp.453-460
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• 1998

The purpose of this study was to analyze their status of underground storage tank(UST) facilities and level of soil contamination, and to establish its management criteria. DB program was developed to analyze the correlation between specific characteristic of UST and level of soil contamination. For a suitable management of UST, leakage monitoring and inspection method of UST was investigated. Inspection period was established based on the leakage rate. The most dominant factor for leakage seemed to be caused by the corrosion. Therefore, main factor, construction method and installation year of UST, and corrosion protection system were suggested for optimal protection of UST. Considering the present management status of UST in Korea, inspection and management criteria of UST should be accomplished in term of contamination protection of leakage, and flexible regulation act should be introduced for each specific site.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.4
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• pp.57-62
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• 2005

Satellite contamination from back-scattered molecules has long been analyzed using the BGK theory or the DSMC technique which are rather inefficient in that they are complicated or take a long time in the analysis. This study presents a new technique of estimating the back-scattering contamination, which is very simple and easy to use like the view factor method and also very accurate. This method, called the modified view factor method, is equivalent to the DSMC in so far as the molecular thermal velocity is much smaller than the satellite velocity and the mean free path much longer than the satellite.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.4
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• pp.541-546
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• 2012

This study investigates the detection system of oil pollution level using single optical fiber sensor. This study focus on sensing of oil pollution by moisture and iron powder which are representatives of oil pollution factor. In addition, It is placed that the water and iron powder as an oil pollution factor in the oil tank which is the oil circulation in. The oil pollution detection system was measured by the changing of intensity of light and sensing gap. The result of this experimentation not only confirmed the contamination by moisture volume in the oil tank from the section 190ppm to 540ppm, but also monitored the contamination by iron volume from the section 1200ppm to 3500ppm. This study confirmed effectiveness of this detection system using optical fiber sensor. There is expectations of measuring another section by various optical fiber sensor.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.199-202
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• 2001

This paper presents the correlation on the contamination degree and weather conditions using the multiple regression of the statistic method. The cotamination is a significant factor in the insulation system. The major factor is natural contamination, and the most is the salt. The salt contamination is occured by the weather conditions. The weather contaminations are wind, precipitation, temperature, relative humidity, etc. The effects of those are different, and the correlation is showed numerically by using the multiple regression method of the statistic method. With this, the estimation of the equivalent salt deposit density(ESDD) becomes possible by the changes of the weather conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05e
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• pp.49-52
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• 2003

The performance of insulators under contaminated conditions is the underlying and the most factor that determines insulation design for outdoor applications, Among the contamination factors, The sea salt is the most dangerous factor, and the salt factor have closed relation with climatic conditions, such as wind, temperature, humidity and so on, Effect of these factors to insulation system is different of each other, and need to show the correlation by multiple regression analysis techniques. In this paper, predicted and analyzed equivalent salt deposit density (ESDD) by change climatic condition through multiple regression analysis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05c
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• pp.27-30
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• 2002

In this paper, we were investigated leakage current properties of outdoor insulator on climatic environmental factor. Contamination is one of the most important factor to determine the performance of insulator. Thus, it is very important to exam the contamination degree on the outdoor insulator. There are many limits, such as reliability of data, interval of measurement and similarity of environmental conditions, in conventional method. So, we measured phase and leakage current of outdoor insulator using the temperature & humidity chamber. In this investigation, phase difference was measured to compare the variance of phase difference with the contamination degree and relative humidity.

• Journal of radiological science and technology
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• v.22 no.2
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• pp.47-51
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• 1999

We calculated the energy distribution and the percentage depth-dose at 10 cm in a $10{\times}10\;cm^2$ with a photon beam at SSD of 100 cm by using a Monte Carlo Simulation. PDD is used as a beam-quality specifier for radiotherapy beams. It is better than the commonly used values of TPR or nominal accelerating potential. The presence of electron contamination affects the measurement of PDD, but can be removed by the use of a 0.1 cm lead filter. It reduces surface dose from contaminant electrons from the accelerator by more than 90% for radiotherapy beams. The filter performs best when it is placed immediately below the head. An electron-contamination correction factor is introduced to correct for electron contamination from the filter and air. It converts PDD which includes the electron contamination with the filter in place into PDD for the photons in the filtered beam. The correction factor can be used to determine stopping-power ratio. Calculations show that the values of water-to-air slopping power ratio in the unfiltered beam are related to PDD.