• Journal of radiological science and technology
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• v.44 no.4
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• pp.301-306
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• 2021

The skull has peripheral organs such as the crystalline lens and thyroid gland, which are highly radiosensitive, but the examination is performed without considering the uneven dose distribution due to the heel effect at the time of the current Skull Town's examination. However, no studies have been conducted on the exposure dose of surrounding organ tissues due to the difference in image density due to the heel effect and the non-uniformity of the dose. Using the cathode (-) and anode (+) set on the Tube to measure the scattered radiation along the Tube direction as a guide, change 30° and 37° in the cathode direction and 30° and 37° in the anode direction. It was given and investigated 5 times to obtain scattered radiation. image measurements were SNR, PSNR, RMSE, and MAE. Measurement results Measurement results of surrounding organ doses when the Tube direction was 30° and 37° The dose was low when the direction was cathodic in all organs (p<0.000). Both cathodes were higher in the image measurements(p<0.04). Continuous research may be needed for diagnostically valuable imaging and minimization of patient exposure dose.

• Journal of Audiology & Otology
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• v.23 no.2
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• pp.76-82
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• 2019

Background and Objectives: Noise levels and room acoustic parameters at a tertiary referral hospital, Seoul National University Hospital (SNUH) in Korea, are investigated. Materials and Methods: Through a questionnaire, acoustically problematic rooms are identified. Noise levels in emergency rooms (ERs) and intensive care units (ICUs) are measured over about three days. Acoustically critical and problematic rooms in the otolaryngology department are measured including examination rooms, operating rooms, nurse stations, receptions, and patient rooms. Results: The A-weighted equivalent noise level, L_Aeq, ranges from 54 to 56 dBA, which is at least 10 dB lower than the noise levels of 65 to 73 dBA measured in American ERs. In an ICU, the noise level for the first night was 66 dBA, which came down to 56 dBA for the next day. The noise levels during three different ear surgeries vary from 57 to 62 dBA, depending on the use of surgical drills and suctions. The noise levels in a patient room is found to be 47 dBA, while the nurse stations and the receptions have high noise levels up to 64 dBA. The reverberation times in an operation room, examination room, and single patient room are found to be below 0.6 s. Conclusions: At SNUH, the nurse stations and receptions were found to be quite noisy. The ERs were quieter than in the previous studies. The measured reverberation times seemed low enough but some other nurse stations and examination rooms were not satisfactory according to the questionnaire.

• Korean Journal of Audiology
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• v.23 no.2
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• pp.76-82
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• 2019

Background and Objectives: Noise levels and room acoustic parameters at a tertiary referral hospital, Seoul National University Hospital (SNUH) in Korea, are investigated. Materials and Methods: Through a questionnaire, acoustically problematic rooms are identified. Noise levels in emergency rooms (ERs) and intensive care units (ICUs) are measured over about three days. Acoustically critical and problematic rooms in the otolaryngology department are measured including examination rooms, operating rooms, nurse stations, receptions, and patient rooms. Results: The A-weighted equivalent noise level, L_Aeq, ranges from 54 to 56 dBA, which is at least 10 dB lower than the noise levels of 65 to 73 dBA measured in American ERs. In an ICU, the noise level for the first night was 66 dBA, which came down to 56 dBA for the next day. The noise levels during three different ear surgeries vary from 57 to 62 dBA, depending on the use of surgical drills and suctions. The noise levels in a patient room is found to be 47 dBA, while the nurse stations and the receptions have high noise levels up to 64 dBA. The reverberation times in an operation room, examination room, and single patient room are found to be below 0.6 s. Conclusions: At SNUH, the nurse stations and receptions were found to be quite noisy. The ERs were quieter than in the previous studies. The measured reverberation times seemed low enough but some other nurse stations and examination rooms were not satisfactory according to the questionnaire.

• Child Health Nursing Research
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• v.14 no.1
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• pp.5-13
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• 2008

Purpose: This study was done to describe utilization status of emergency medical service for children at one university affiliated hospital located in Seoul. Data were obtained from the medical records of patients under 13 years of age who visited the ER from January 1 to December 31, 2006. Method: Medical records missing the time of discharge were excluded in the analysis of waiting time, which resulted in 19,766 cases. Data were analyzed using SPSS WIN 14.0 version. Result: There were slightly more boys (58.4%), average age of the children was 3.97 years of age. More children at the aged 1 to 3 years (51.3%) visited the ER. Fever was the most frequent complaint: 5,180 cases (24.38%). The other complaints were head or facial laceration (10.55%), vomiting (9.63%), abdominal pain (8.06%), cough (7.67%), and painful limb swelling (6.34%). Average waiting time before the first medical examination was 17 minutes, and average ER stay time was 3 hours and 23 minutes. Conclusion: The results suggest the need to assign a nurse specialist for pediatric ER to provide more efficient care for the children. Also, extra staff assignment during the evening shift or extending office hours of local pediatricians should be considered.

• Fire Science and Engineering
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• v.17 no.2
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• pp.10-16
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• 2003

The main purpose of this study is to raise the point at issue and to propose reform direction about the current performance criteria of fire resistance through the examination of the fire resistance required for each use of compartment by using performance-based fire safety design method. To examine the performance criteria of fire resistance, this study compared the equivalent time of fire exposure which was calculated by using time-equivalent formulae with the required fire resistance time determined by existing prescriptive code, and surveyed factors such as the fire load energy density, ventilation factor, fire compartment materials and fire compartment geometry in order to calculate the equivalent time of fire exposure.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.218-224
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• 1998

Long-term exposure of cigarette smoke or air pollutants to human can induce damages in the airway mucociliary function and can be closely related to the irritation and sputum formation in the respiratory system. This study was undertaken to investigate whether rat trachea can be used as a tool for evaluating the cigarette smoke quality. It was identified that, through the examination with inverted microscope, ciliary beating in 1 mm long cut of nat trachea ring was continued for at least 48 hours in saline solution at $25^{\circ}C$. The ciliostasis time in a KCN solution as a positive control was decreased with increasing the concentration of KCN. There were no significant differences in the ciliostasis time by body weight and individual variation of rats. Ciliotoxicity of whole smoke trapped in saline was not significantly changed by aging for more than 6 hrs. The ciliostasis time was in inverse proportion to the number of sample cigarettes applied. As moisture in the cigarette was increased, ciliostasis time was linearly increased. Therefore, these data indicate that the ciliotoxicity test using rat trachea in vitro can be applied to evaluate the cigarette smoke quality and to search factors for the irritation and sputum formation by cigarette smoke as well as air pollutants.

• Journal of Korea Foundry Society
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• v.30 no.5
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• pp.161-166
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• 2010

In this examination, the effect of Sr addition and holding time on microstructure of Al-10.5wt%Si-2wt%Cu secondary die-casting alloy was investigated. Degree of undercooling was improved with increasing the Sr content in this alloy. Up to 0.02wt%Sr addition, acicular and lamellar eutectic structure was observed in the microstructure. Meanwhile, the eutectic Si was modified toward the fine fibrous form by increasing Sr content with more than 0.03wt% and holding time of the melt. The well- modified alloys showed decreased eutectic silicon size from 3.25 ${\mu}m$ to less than 0.8 ${\mu}m$. From these results, the optimal strontium content and holding time were identified on the Al-10.5wt%Si-2wt%Cu secondary die-casting alloy.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.788-792
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• 2009

Gamma $({\gamma})-irradiation$ can be used to control pathogens such as Vibrio vulnificus in seafood. The effects of irradiation on microbial cell populations (%) have been studied in order to develop detection methods for irradiated foods. The method used in this study was ethidium bromide monoazide (EMA) real-time polymerase chain reaction (PCR), using V. vulnificus specific primer, EMA, and $SYBR^{(R)}$ Green to discriminate between ${\gamma}-irradiated$ and non-irradiated cells. Confocal microscope examination showed that ${\gamma}-irradiation$ damaged portions of the cell membrane, allowing EMA to penetrate cells of irradidated V. vulnificus. ${\gamma}-Irradiation$ at 1.08 KGy resulted in log reduction ($-1.15{\pm}0.13$ log reduction) in genomic targets derived from EMA real-time PCR. The combination cold/heat shock resulted in the highest ($-1.74{\pm}0.1$ log reduction) discrimination of dead irradiated V. vulnificus by EMA real-time PCR.

• Current Research on Agriculture and Life Sciences
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• v.32 no.3
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• pp.125-130
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• 2014

This study used transmission electron microscopy (TEM) to investigate the micro-morphological features of two formaldehyde to urea (F/U) mole ratio liquid urea-formaldehyde (UF) resins with three hardener levels as a function of the curing time. The micro-morphological features of the liquid UF resins were characterized after different curing times. As a result, the TEM examination revealed the presence of globular/nodular structures in both liquid UF resins, while spherical particles were only visible in the low F/U mole ratio resins. The high F/U mole ratio liquid UF resins also showed extensive particle coalescence after adding the hardener, along with the appearance of complex filamentous networks. When the resins were cured with a higher amount of hardener and longer curing time, the spherical particles disappeared. For the low mole UF resins, the particles tended to coalesce with a higher amount of hardener and longer curing time, although discrete spherical particles were still observed in some regions. This is the first report on the distinct features of the crystal structures in low F/U mole ratio UF resins cured with 5% hardener and after 0.5 h of curing time. In conclusion, the present results indicate that the crystal structures of low F/U mole ratio UF resins are formed during the curing process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1077-1085
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• 1997

This study was carried out to elucidate the utilization of the fusant for shortening the ripening time by making an observation of the microstructure and the profile of component change. In ripening cheese, moisture content of the sample treated with tested strain is not a remarkable difference among the test samples. With an increase of the ripening time, L. helveticus showed the highest increase in protein content, followed by fusant, and then L. bulgaricus. The fat content of all starters was gradually decreased while it was it was rapidly decreased after 7 days. The pH of all starters was gradually decreased when the ripening time increased. The titratable acidity was greatly increased between a 9th day and a 15th day ripening. In investigating the light microscopic microstructure of ripened cheese samples, the sample treated with fusant indicated little difference from the other starters in decomposition of protein and fat components by microbial enzymes. In SEM observation, the structure of all cheese samples was uniform and the rough texture was converted into smooth texture by the interaction of cheese components and the abscission of single bond in casein matrix when the ripening time is increased. The fusant showed similar results in the examination of component change and its microstructure compared with the other starters. Therefore, it was revealed that the fusant can be partially used as a cheese starter instead of conventional starters by replacing them or combining them together with the other starters for shortening the ripening time.