• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2002.05a
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• pp.139-142
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• 2002

This study carried out to evaluate TMDI(theoretical maximum daily intake) and EDI(estimated daily intake) for Korean by using MRLs, food intake, residue data, and correction factors and compare with ADI(acceptable daily intake) in order to estimate the health risk based on the pesticide exposure.

• Journal of Food Hygiene and Safety
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• v.14 no.2
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• pp.201-215
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• 1999

Limited information is available on the acceptability of Korean MRLs(maximum residue limits) and the health risk based on the pesticide exposure by food intake. The aim of this study was to evaluate TMDI(theoretical maximum daily intake) and EDI(estimated daily intake) for Korean by using MRLs, food intake, residue data, and correction factors, and compare with ADI(acceptable daily intake) in order to estimate the health risk based on the pesticide exposure. The study was performed in three steps. In the frist step, the residual pesticides in each category of food were investigated using the pesticide residue analytical data(1995-96) from officially approved organizations and the analytical data for poultry was adopted from Korean food code method. In the second step, TMDI was estimated from MRLs and food factors, and was compared with ADI. In the third step, the effectiveness of each culinary treatment (washing, peeling, steaming, boiling, and salting) was evaluated and EDI was calculated using pesticide residue data, food factor, and correction factor by treatment. TMDI obtained from MRLs and food intake, and food intake was summed as 1,100.99 g, which was 79.1% of total consumption. The percent ratio of TMDI to ADI for 156 pesticides was mostly below 80% and only 30 pesticides exceeded the ADI. In particular, non-treated EDI from pesticide residue data and food intake was summed up to about 43 $\mu\textrm{g}$/day/capita, and the rank was procymidone(8.6 $\mu\textrm{g}$) > maleic hydrazide(8.2 $\mu\textrm{g}$) > EPN(3.7 $\mu\textrm{g}$) > deltamethrin(3.5 $\mu\textrm{g}$) > cypermethrin(3.0 $\mu\textrm{g}$). The treated EDI calculated from pesticide residue data, food intake, and correction factor by culinary treatment was summed up to 13.7 $\mu\textrm{g}$/day/captia. The percentage of ADI was TMDI(79.74%) > non-treated EDI (0.17%) > treated EDI (0.04%), and the exposure level of Korean population to whole pesticides was below the level to produce health risk. Oncogenic risk of five pesticides used in Korea whose oncogenic potency(Q*) was known were assessed from TMDI and treated EDI. Dietary oncogenic risk for Korean was estimated to be 2.0$\times$10-3 on the basis of TMDI, 8.3$\times$10-7 on the basis of treated EDI. The oncogenic risk from TMDI exceeded the risk level(1$\times$10-6) of EPA, whereas the oncogenic risk from treated EDI and real exposure level lower than that of EPA.

• Wind and Structures
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• v.26 no.3
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• pp.129-146
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• 2018

Extreme wind speed analysis has been carried out conventionally by assuming the extreme series data is stationary. However, time-varying trends of the extreme wind speed series could be detected at many surface meteorological stations in China. Two main reasons, exposure change and climate change, were provided to explain the temporal trends of daily maximum wind speed and annual maximum wind speed series data, recorded at Hangzhou (China) meteorological station. After making a correction on wind speed series for time varying exposure, it is necessary to perform non-stationary statistical modeling on the corrected extreme wind speed data series in addition to the classical extreme value analysis. The generalized extreme value (GEV) distribution with time-dependent location and scale parameters was selected as a non-stationary model to describe the corrected extreme wind speed series. The obtained non-stationary extreme value models were then used to estimate the non-stationary extreme wind speed quantiles with various mean recurrence intervals (MRIs) considering changing climate, and compared to the corresponding stationary ones with various MRIs for the Hangzhou area in China. The results indicate that the non-stationary property or dependence of extreme wind speed data should be carefully evaluated and reflected in the determination of design wind speeds.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.302-302
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• 2000

This paper presents the measurement and correction of PCB alignment errors for PCB-manufacturing machines. The conventional PCB-manufacturing machine doesn't have enough accuracy to accommodate the demand for high-resolution circuit pattern and high-density mounting capacity of electronic chips. It is because of alignment errors of PCB loaded to the PCB-manufacturing machine. Therefore, this study focuses on the development of the system which is able to measure and correct alignment errors whit high-accuracy. An automatic optical inspection part measures the PCB alignment error using two cameras, and the high-accuracy 3-axis stage makes correct of these error. The operating system is run in the environment of Window 98 (or NT). Finally we implemented this system to PCB screen printer and PCB exposure system.

• Journal of Broadcast Engineering
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• v.22 no.3
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• pp.327-338
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• 2017

Exposure fusion is a typical image fusion technique to generate a high dynamic range image by combining two or more different exposure images. In this paper, we propose block-based exposure adjustment considering unique characteristics of human visual system and improved saturation measure to get weight map. Proposed exposure adjustment artificially corrects intensity values of each input images considering human visual system, efficiently preserving details in the result image of exposure fusion. The improved saturation measure is used to make a weight map that effectively reflects the saturation region in the input images. We show the superiority of the proposed algorithm through subjective image quality, MEF-SSIM, and execution time comparison with the conventional exposure fusion algorithm.

• Journal of Astronomy and Space Sciences
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• v.21 no.4
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• pp.399-416
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• 2004

The FIMS (Far-ultraviolet IMaging Spectrograph), the main payload onboard the first Korean science satellite STSAT-1, has performed various observations since its launch on September 2003. It has been found that the attitude informations provided by spacecraft bus system have a time offset problem, and the problem has been extensively studied. After the time offset correction, boresight offsets between FIMS fields of view, of long and short wavelength bands, respectivley, and spacecraft attitude systems, which are mainly due to alignment error between the FIMS and spacecraft mechanical systems, were calculated through the observations of well known calibration targets. Monthly status and precision of the attitude information are also described. Correction methods for spatially variable exposure, intrinsic to FIMS data, are discussed. These results are essential to the FIMS data analysis, and will be used as references for subsequent studies on more accurate attitude corrections.

• Journal of Korean society of Dental Hygiene
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• v.12 no.4
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• pp.695-705
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• 2012

Objectives : The purpose of this study is to evaluate the appearance of having relationship between the exposure to lead and cadmium and the dental caries targeting adults in the Republic of Korea. Methods : The study was designed as a cross-sectional study, using the data of the Fourth Korea National Health and Nutrition Examination Survey. The subjects as 1,966 people, who were confirmed the appearance of dental caries among 1,991 people of having been offered the heavy-metal concentration in blood. Statistical analysis was conducted using SPSS 19.0, according to complex sampling design. Results : As a result of multi-variate analysis on factors of dental caries, in Model I without correction, the gender, age, educational level, appearance of lifelong smoking, daily toothbrushing frequency, appearance of using dental floss, and subjective oral health status were recognized as important factors. In Model II with correction of gender and age, the educational level, daily toothbrushing frequency, and subjective oral health status were recognized as statistically significant factors. In Model III with correction of all factors, the gender, age, educational level, appearance of using dental floss, and subjective oral health status were functioning as statistically significant factors. As a result of statistically analyzing relationship between the exposure to lead and cadmium and the dental caries targeting adults, it was analyzed that there is no significant correlation. However, in case of lead, the tendency of being grown the cross ratio of dental caries could be examined in model I, which didn't correct disturbance factor, model II, which corrected gender and age, and model III, which corrected all variables of disturbance factor. Conclusions : The exposure to lead and cadmium was indicated to have no relationship with adults' dental caries. However, a continuous research of relationship was considered to be necessary by using Korea National Health and Nutrition Examination Survey, which is surveyed in the future.

• Journal of the Korean Society of Radiology
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• v.12 no.1
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• pp.79-83
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• 2018

In this paper, we measured and analyzed the dose correction factor, absorbed dose linearity, peak voltage X-ray response, angular dependence. Exposure dose correction factor, absorbed dose linearity, and peak voltage linearity using the medical X-ray generator were all in accordance with IEC-62387-1 (2007). The reference to the dosimetry direction at 0, 30, and 60 degrees relative to baseline radiation exposure was -29% (${\pm}30^{\circ}$) and + 67% (${\pm}60^{\circ}$). The values measured at $30^{\circ}$ were -8% lower than the standard and -18% lower than the standard at $60^{\circ}$. Therefore, the effect of direction should be corrected when using OSL dot dosimeter.

• Journal of radiological science and technology
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• v.4 no.1
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• pp.45-53
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• 1981

In examinations of the stomach roentgenography, it is imperative to obtain adequate film density throughout all its different regions. Therefore, it is necessary to use more sophiscated exposure techniques. In order to achieve these purpose, the radiologic technologists must be measured abdominal thickness in variations with patient positions. In consideration of these problem, the author was made an experiment on correction method of kVp and mAs by abdominal thickness in roentgenography of the stomach. The results were summarized as follws: 1. When the patient in erect position, abdominal thickness was the most thickened at the level of 3cm inferior to umbilicus without regard to body habitus and it was the most thickened at the level of 3cm superior to umbilicus in prone and supine position. 2. As a result of measuring film density for stomach, the adequate film density was represented from 0.70 to 2.49 in erect position and $0.28{\sim}1.18$ in supine position, $0.5{\sim}2.45$ in prone position. 3. In order to obtain uniform film density in 1.25, the correction factor for kVp by abdominal thickness was represented average ${\pm}4.5kVp\;per\;{\pm}1cm$ in a fixed 50 mAs, and average ${\pm}3.9kVp\;per\;{\pm}1cm$ in a fixed 100mAs. 4. In order to obtain uniform film density in 1.25, the correction factor for mAs by abdominal thickness was represented average ${\pm}30.9%\;per\;{\pm}1cm$ in a fixed 80 kvp and ${\pm}26.9%\;per\;{\pm}1cm$ in a fixed 100kVp.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.2
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• pp.33-38
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• 2014

Purpose Auto exposure control (AEC) in SPECT/CT automatically controls the exposure dose (mA) according to patient's shape and size. The aim of this study was to evaluate the effect of AEC in SPECT/CT on exposure dose reduction and image quality. Materials and Methods The model of SPECT/CT used in this study was Discovery 670 (GE, USA), Smart mA for AEC; and $^{99m}Tc$ as a radioisotope. To compare SPECT and CT images by CT exposure dose variation, we used a standard technique set at 80, 100, 120, 140 kVp, 10, 30, 50, 100, 150, 200, 250 mA, and AEC at 80, 100, 120, 140 kVp, 10-250 mA. To evaluate resolution and contrast of SPECT images, triple line phantom and flangeless Esser PET phantom were used. For CT images, noise and uniformity were checked by anthropomrphic chest phantom. For dose evaluation to find DLP value, anthropomorphic chest phantom was used and the CT protocol of torso was applied by standard technique (120 kVp, 100 mA) and AEC (120 kVp, 10-250 mA). Results When standard and AEC were applied, the resolutions at SPECT images with attenuation correction (AC) were the same as FWHM by center 3.65 mm, left 3.48 mm, right 3.61 mm. Contrasts of standard and AEC showed no significant difference: standard 53.5, 29.8, 22.5, 15.8, 6.0, AEC 53.5, 29.6, 22.4, 15.7, 6.1 In CT images, noise values at standard and AEC were 15.4 and 18.5 respectively. The application of AEC increases noise but the value of coefficient variation were 33.8, 24.9 respectively, obtaining uniform noise image. The values of DLP at standard and AEC were 426.78 and 352.09 each, which shows that the application of AEC decreases exposure dose more than standard by approximately 18%. Conclusion The results of our study show that there was no difference of AC in SPECT images based on the CT exposure dose variation at SPECT/CT images. It was found that the increased CT exposure dose leads to the improvement of CT image quality but also increases the exposure dose. Thus, the use of AEC in SPECT/CT contributes to obtaining equal AC SPECT images, and uniform noise in CT images while reducing exposure dose.