• Journal of radiological science and technology
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• v.39 no.2
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• pp.209-225
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• 2016

In this study, radiation workers who work in nuclear medicine department were analyzed to find the cause of differences of radiation exposure from General Characteristic, Knowledge, Recognition and Conduct, especially females working on nuclear medicine radiation, in order to pave the way for positive defense against radiation exposure. The subjects were 106 radiation workers who were divided into two groups of sixty-four males and forty-two females answered questions about their General Characteristic, Knowledge, Recognition, Conduct, and radiation exposure dose which was measured by TLD (Thermo Luminescence Dosimeter). The results of the analysis revealed that as the higher score of knowledge and conduct was shown, the radiation exposure decreased in female groups, and as the higher score of conduct was shown, the radiation exposure decreased in male groups. In the correlation analysis of female groups, the non-experienced in pregnancy showed decreasing amount of radiation exposure as the score of knowledge and conduct was higher and the experienced in pregnancy showed decreasing amount of radiation exposure as the score of recognition and conduct was higher. In the regression analysis on related factors of radiation exposure dose of nuclear medicine radiation workers, the gender caused the meaningful result and the amount of radiation exposure of female groups compared to male groups. In the regression analysis on related factors of radiation exposure dose of female groups, the factor of conduct showed a meaningful result and the amount of radiation exposure of the experienced in pregnancy was lower compared to the non-experienced. The conclusion of this study revealed that radiation exposure of female groups was lower than that of male groups. Therefore, male groups need to more actively defend themselves against radiation exposure. Among the female groups, the experienced in pregnancy who have an active defense tendency showed a lower radiation exposure. Thus, those who have never been pregnant need to have a more active defensive conduct for the future possibility of pregnancy.

• Journal of the Korean Society of Radiology
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• v.84 no.5
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• pp.1123-1133
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• 2023

Purpose Our study aimed to evaluate the association between automated quantified body composition on CT and pulmonary function or quantitative lung features in patients with chronic obstructive pulmonary disease (COPD). Materials and Methods A total of 290 patients with COPD were enrolled in this study. The volume of muscle and subcutaneous fat, area of muscle and subcutaneous fat at T12, and bone attenuation at T12 were obtained from chest CT using a deep learning-based body segmentation algorithm. Parametric response mapping-derived emphysema (PRM^emph), PRM-derived functional small airway disease (PRM^fSAD), and airway wall thickness (AWT)-Pi10 were quantitatively assessed. The association between body composition and outcomes was evaluated using Pearson's correlation analysis. Results The volume and area of muscle and subcutaneous fat were negatively associated with PRM^emph and PRM^fSAD (p < 0.05). Bone density at T12 was negatively associated with PRM^emph (r = -0.1828, p = 0.002). The volume and area of subcutaneous fat and bone density at T12 were positively correlated with AWT-Pi10 (r = 0.1287, p = 0.030; r = 0.1668, p = 0.005; r = 0.1279, p = 0.031). However, muscle volume was negatively correlated with the AWT-Pi10 (r = -0.1966, p = 0.001). Muscle volume was significantly associated with pulmonary function (p < 0.001). Conclusion Body composition, automatically assessed using chest CT, is associated with the phenotype and severity of COPD.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.1
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• pp.88-93
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• 1994

This study is concerned with an analytic derivation of the probability density function applicable for wave heights in finite water depth using two different methods. As the first method of the study, a probability density function is developed by applying a series of polynomials which is orthogonal with respect to Rayleigh probability density function. The newly derived probability density function is compared with the histogram constructed from wave data obtained in finite water depth which indicate strong non-Gaussian characteristics. Although the probability density represents the histogram very well. it has negative density at large values. Although the magnitude of the negative density is small. it negates the use of the distribution function fer estimating extreme values. As the second method of the study, a probability density function of wave height is developed by applying the maximum entropy method. The probability density function thusly derived agrees very well with the wave height distribution in shallow water, and appears to be useful in estimating extreme values and statistical properties of wave heights in finite water depth. However, a functional relationship between the probability distribution and the non-Gaussian characteristics of the data cannot be obtained by applying the maximum entropy method.

• Journal of the Korean Vacuum Society
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• v.16 no.2
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• pp.122-127
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• 2007

In this research, amophous carbon films (a-C, a-C:H, a-C:N) were synthesized by closed-field unbalanced magnetron (CFUBM) sputtering using graphite target. We also fabricated amorphous carbon films with applying negative DC bias voltage of 200 V in during the deposition in working pressure. Also, a-C:H and a-C:N films was synthesized by adding acethylene($C_{2}H_{2}$) and nitrogen(N) gases of 4 and 3 sccm into Ar pressure. The a-C:H film synthesized at -200 V exhibited the maxumum hardness of 26.3 GPa, the smooth surface of 0.1 nm and the good adhesion of 30.5 N. And a-C:N film synthesized at -200 V exhibited at -200 V exhibited the best adhesion of 32 N. This paper examined the effect of $C_{2}H_{2}$ gas, $N_{2}$ gas and negative DC bias voltage as the parameter for improving the physical properties and the relation between structral and physical properties of carbon films.

• Journal of Bio-Environment Control
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• v.13 no.2
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• pp.67-72
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• 2004

Red peppers(Capsicum annuum L.), 'Geumtap' and 'Bugang', were cultivated at main producing areas in Korea, and harvested 4 times in 1998 and 1999. The relationships between internal qualities such as reducing sugar, capsaicinoids, and vitamin C contents, and regional climatic elements such as total accumulated air temperature, total amount of precipitation and sunshine duration during the fruit growing periods were compared. The amount of reducing sugar increased as the harvest time was late. Capsaicinoids content varied by harvest dates and cultivated years. Vitamin C content was influenced by cultivated year more than cultivars. Reducing sugar content showed a negative relationship with total amount of precipitation but showed a positive relationship with sunshine duration. There were negative relationship between the contents of capsaicinoids and vitamin C and total amount of precipitation.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.90-94
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• 1995

Post emergence herbicidal activities$(pI_{50})$ of X-substituted phenylvinylsulfone derivatives(S) in-vivo against rice(Oryza sativa L.), Barnyard grass(Echinochloa crus-galli) and Pickerelweed(Monochoria vaginalis Presl) were measured by the pot test under paddy conditions. The (S) showed herbicidal symptom rapidly with lower activity(average $pI_{50}=2.0$) as proherbicide, which was excellent tolerance to rice. The structure activity relationships(SAR) were analyzed using such a physicochemical parameters as hydrophobic$({\pi})$ and molecular orbital(MO) quantity by the multiple regression technique, and discussed with quantum pharmacology. The herbicidal activities were related to the hydrophobic$({\pi})$ effect of X-substituent and orbital(HOMO & LUMO) energy. In case of Pickerelweed, the effect was rationalized by parabolic function of ${\pi}$ constant, where the optimal value of ${\pi}$ was 1.10. An increase in hydrophobicity and negative orbital energy by the electron attracting X-substituent may contribute to the herbicidal activity. Based on results proposed from SAR analysis, the mode of herbicidal action could be assumed.

• The Journal of the Korea Contents Association
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• v.14 no.7
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• pp.457-467
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• 2014

In order to improve organization performance by CEO's leadership, the control systems have to be designed in accordance with CEO's strategic orientation. A management control systems (MCS) is a system which gathers and uses information to evaluate the performance of different organizational resources like human, physical, financial and also the organization as a whole considering the organizational strategies. The current study is conducted with the objective to explore the effects of CEO's Characteristics (Risk-taking tendency, and Achievement motivation) and control types (Behavioral control, and Result control) on organization performance. The characteristics of ceo - behavior control and risk-taking propensity - results in significantly positive effect on management control. On the other hand, risk-taking propensity has influence negatively on behavior control. The behavioral control is received negative influence from risk-taking propensity. and it received positive influence from motivation. and then it has effect on organization performance(indirct effect). To achieve the purpose of this study, Structural Equation Model (SEM) has been applied.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.3
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• pp.197-202
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• 2014

The efficiency of a catalytic converter depends on the flow distribution across a system's chemically active substrate. If irregularities or non-uniform flow patterns exist, the system's conversion efficiency decreases, whereas the manufacturing cost increases. Therefore, it is important to analyze the internal flow of a catalytic converter. In this study, flow pattern measurements along the minor axis were recorded at the mid and exit planes of a ceramic honeycomb catalytic converter at flow rates of 37.8 l/s and 94.4 l/s. Flow distributions of the measurement plans were compared with an automotive company's computed velocity profiles. Measurements along the minor axis showed uneven velocity profiles. The ${\upsilon}$-velocity components between the honeycomb bricks were small but somewhat erratic opposite the intake side of the converter, however, they became flatter in measurements recorded near the intake entrance. For almost all velocity values, the computer model suggested velocities greater than the measured values.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.3
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• pp.63-72
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• 2011

Benzalkonium chloride is most widely used in S. Korea as a disinfectant in livestock husbandry. Inhibition of biogas potentials were investigated with three different doses of benzalkonium chloride in swine slurry. The system was operated at batch mode. The inhibition rates were 10%, 30~40% and >70% at the dose of 10ppm, 40ppm and 80ppm, respectively assuming it was zero percent in case of no dose. Enzymatic activities were analyzed to determine the enzymatic type which was inhibited by benzalkonium chloride. The acid phosphatase, alkaline phosphatase and protease were shown negatively correlated with biogas potential. Correlation of ${\alpha}$-glucosidase and biogas potentials was observed not high (p<0.01, r=-0.426) while benzalkonium chloride (r=-0.853, p<0.01) and acid phosphatase (p<0.01) with biogas potentials were significantly and negatively correlated. The effect of benzalkonium chloride on Escherichia coli were also evaluated by disc diffusion method. As increase of benzalkonium concentration, inhibition zone of anaerobic bacteria was extended. It revealed that benzalkonium chloride significantly deteriorated biogas potential through inhibition of acetogenic bacteria.

• Journal of Nutrition and Health
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• v.47 no.1
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• pp.33-44
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• 2014

Purpose: Elevated serum phosphorus and potassium levels are a major problem for hemodialysis (HD) patients. Hyperphosphatemia and hyperkalemia are closely related to intake of dietary phosphorus and potassium. Methods: This study was conducted in order to investigate the effects of food consumed on serum phosphorus and potassium levels in 48 HD patients (20 males and 28 females). We collected anthropometric data, biochemical parameters, and dietary data of the subjects. Dietary data for usual intake were obtained by use of a food-frequency questionnaire (FFQ) consisting of 21 food items. Results: The mean body mass index (BMI) was $22.2{\pm}3.0kg/m^2$, mean serum phosphorus level was $4.50{\pm}1.52mg/dl$, and mean serum potassium level was $4.74{\pm}0.73mEq/l$. Hyperphosphatemia (> 4.5 mg/dl) was found in 45.8% of subjects, and hyperkalemia (> 5.0 mEq/l) in 35.4%. Subjects who took medication only were 56% of total, and those who took medication with dietary therapy were 27%. Patients with medication and dietary therapy showed significantly lower serum phosphorus levels compared to patients with medication only (p < 0.05). Mean duration of HD was $7.9{\pm}7.3$ years and it showed positive correlation with serum potassium levels (p < 0.05). Serum phosphorus levels showed positive correlation with intake of mixed grains and soybean milk (p < 0.05). Serum potassium levels showed positive correlation with intake of mixed grains (p < 0.01), potatoes, fish, and high-potassium vegetables (p < 0.05). On the other hand, intake of white rice showed negative correlation with serum potassium levels (p < 0.05). Conclusion: The results of our study suggest that intake of white rice rather than mixed grains is an important factor in sustaining normal serum phosphorus and potassium levels. In addition, limiting intake of soybean milk, potatoes, and fish to under three serving per week is recommended. Finally, conduct of a strict dietary therapy along with medical treatment is desirable because inappropriate food intake increases serum phosphorus and potassium levels to a higher than normal range.