• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.94-97
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• 2014

Purpose: Standardized uptake value (SUV) is a simple semi-quantitative method that can measure the ratio of the tissue radioactivity between the tumor and normal. SUV is commonly used in PET/CT, however, SUV is affected by various factor. The purpose of this study was to evaluate the impact of the residual activity on SUV depending on the location of catheter insertion device post injection. Materials and Methods: NEMA IEC Body Phantom was imaged using a Discovery 600 PET scanner. In 22 mm diameter sphere, the different activity of $^{18}F-FDG$ (7.4, 14.8, 22.2, 29.6, 37, 55.5 MBq) was filled and background was filled with $^{18}F-FDG$ (5.7 kBq/mL). We scaned the phantom on the assumption that the radioactivity in sphere was residual activity in insertion device. Simulation of PET was divided into three groups based on the location of sphere in Scan FOV (SFOV); inclusion, 1/2 inclusion and exclusion group. Results: Among three groups, the group of excluded sphere showed the highest SUV regardless of the amount of $^{18}F-FDG$ activity. In case of 7.4 MBq, average SUV of inclusion group, 1/2 inclusion and exclusion group was 0.780, 0.840 and 0.896 respectively. However, average SUV of 55.5 MBq showed 0.372, 0.460 and 0.508 with same order. Depend on residual radioactivity in the sphere and position of sphere, the SUV was different minimum of 10.4%, maximum of 62.8%. Conclusion: This study showed that SUV is underestimated as the residual radio-activity is increased. In addition, SUV was a changed according to the position of residual radio-activity. And among the position, exclusion group showed the difference of SUV was lowest. If we measure the residual radio-activity of inserting devices and radio-activity from extra-vasation in the patients, it seems to be more useful in clinical field.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.73-86
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• 2007

Risk-based remediation strategy (RBRS) is a consistent decision-making process for the assessment and response to chemical release based on protecting human health and the environment. The decision-making process described integrates exposure and risk assessment practices with site assessment activities and remedial action selection to ensure that the chosen actions are protective of human health and the environment. The general sequences of events in Tier 1 is as follows: initial site assessment, development of conceptual site model with all exposure pathways, data collection on pollutants and receptors, and identification of risk-based screening level (RBSL). If site conditions do not meet RBSL, it needs further site-specific tier evaluation, Tier 2. In most cases, only limited number of exposure pathways, exposure scenarios, and chemicals of concern are considered the Tier 2 evaluation since many are eliminated from consideration during the Tier 1 evaluation. In spite of uncertainties due to the conservatism applied to risk calculations, limitation in site-specific data collections, and variables affecting the selection of target risk levels and exposure factors, RBRS provides us time- and cost-effectiveness of the remedial action. To ensure reliance of the results, the development team should consider land and resource use, cumulative risks, and additive effects. In addition, it is necessary to develop appropriate site assessment guideline and reliable toxicity assessment method, and to study on site-specific parameters and exposure parameters in Korea.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.9 no.2
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• pp.226-232
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• 2006

Purpose: The aim of this study was to evaluate the influence of leptin on biochemical markers of bone metabolism in childhood obesity. Methods: A total of 50 male children (25 obese and 25 controls) were recruited from the pediatric outpatient clinic at the Chosun University Hospital from November 1st 2005 to May 30th 2006. BMI, body fat percentage, serum leptin, bone-specific alkaline phosphatase (B-ALP), C-terminal propeptide of type 1 collagen (CICP), total deoxypyridinoline crosslinks (total DPD) were measured. The correlations of leptin with BMI, body fat percentage, B-ALP, CICP, total DPD were analyzed by Pearson's correlation. In a multiple stepwise regression analysis, leptin after correction for body weight was evaluated if there was a correlation with biochemical markers of bone formation and resorption respectively. Results: The leptin levels of the obese group were significantly higher than those of the control group (p=0.012). In the obese group, the leptin level was significantly positively correlated with the BMI (r=0.551, p=0.01) and the percentage of body fat (r=0.584, p=0.018). In the obese group, of bone markers, B-ALP (r=-0.613, p=0.026) and CICP (r=-0.583, p=0.037) were negatively correlated with leptin. B-ALP (r=-0.728, p=0.007) and CICP (r=-0.684, p=0.014) were negatively correlated with leptin when corrected for body weight. In the control group, bone markers were not correlated with leptin. In the multiple stepwise regression analyses, there was a negative correlation between the leptin and B-ALP (Y=-39.653X+356.341, p=0.026), CICP (Y=-13.437X+ 116.013, p=0.037) respectively in the obese group. Conclusion: Leptin was a significant factor in the bone formation but not in bone resorption in childhood obesity.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.33-40
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• 2003

The present study was undertaken to find relationships of plasma insulin-like growth factor (IGF)-I and IGF-II concentrations to litter size and lactation performance. Sixty pure-bred Landrace and Yorkshire pigs having similar farrowing weeks which had been selected from a large number of pregnant gilts and sows were divided into low- (<${\mu}$－0.5SD) and high-litter size (>${\mu}$+0.5 SD) lines under a 2 (breed)${\times}$2 (line) factorial arrange of treatments. After adjusting the litter size to nine piglets per sow at farrowing, total litter weight was measured at three weeks postpartum at weaning as an index of milk yield. Blood samples were obtained from the jugular vein at day (d)-90 pregnancy (Px) and at d-15 postpartum. The litter size or the number of piglets born during the present experiment and the average litter size during the entire parities up to the present one were greater in the high-line than in the low-line by 3.7 and 2.4 piglets, respectively (P<0.01); effect of the breed on litter size was not significant. Plasma IGF-II concentration at d-90 Px was greater in the high-line than in the low-line. Litter size and d-90 Px IGF-I concentration were negatively correlated in Landrace (r=－0.46; P<0.05) and tended to be negatively correlated in Yorkshire (r=－0.31; P=0.09), which resulted in a significant negative correlation between these two variables in total animals (r=－0.35; P<0.01). Litter weight at weaning was not different between the two breeds or lines. Relationships between the litter weight and IGF concentration were not consistent across the breed ${\times}$ physiological stage combinations. Results suggest that d-90 Px IGF concentrations may be indicative of the litter size at impending farrowing.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.418-430
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• 2017

The quality of surface water is a very important issue to use various demands like as drinking water, industrial, agricultural and recreational usages. There has been an increasing demand for monitoring water quality of many rivers by regular measurements of various water quality variables. However precise and effective monitoring is not enough, if the acquired dataset is not analyzed thoroughly. Therefore, the aim of this study was to estimate differences of seasonal and regional water quality using multivariate data analysis for each investing tributaries in Han River. Statistical analysis was applied to the data concerning 11 mainly parameters (flow, water temperature, pH, EC, DO, BOD, COD, SS, TN, TP and TOC) for the time period 2012~2016 from 12 sampling sites. The seasonal water quality variations showed that each of BOD, TN, TP and TOC average concentration in spring and winter was higher than that of summer and fall, respectively. In summer each flow rate and average concentration of SS was higher than any other seasons, respectively. The correlation analysis were explained that EC had a strong relationship with BOD (r=0.857), COD (r=0.854), TN (r=0.899) and TOC (r=0.910). According to principal component analysis, five principal components (Eigenvalue > 1) are controlled 98.0% of variations in water quality. The first component included TP, DO, pH. The second component included EC, TN. The third component included SS. The fourth component included flow. The last component included Temp. Cluster analysis classified that spring is similar to fall and winter with water quality parameters. AnyA, WangsA, JungrA and TancA were identified as affected by organic pollution. Cluster analysis derived seasonal differences with investigating sites and better explained the principal component analysis results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.2189-2198
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• 2012

This study was designed to measure the difference in health-related quality of life (HRQOL) among social classes and explore the factors that may explain it. Study subjects were 7,992 Korean adults aged 20-69 from the 4th (2007-2009) Korea National Health and Nutrition Examination Surveys data. We described mean value of EQ-5D index as a HRQOL by class and performed hierarchical multiple regression analysis to find the factors. The result was as follows. In the distribution of EQ-5D index level among social classes, new middle class (class II) had the highest score (0.966 in men and 0.955 in women); upper and middle-upper class (class I) 0.965 in men and 0.936 in women; working class (class IV) 0.958 in men and 0.936 in women; old middle class (class III) 0.955 in men and 0.932 in women; low class (class VI) 0.941 in men and 0.908 in women; and rural self-management class (class V) the lowest score (0.918 in men and 0.866 in women). In men, chronic disease, job stress, education and income level were found to make the difference in the health-related quality of life among social classes; in women, those factors and health behavior explained the difference. In conclusion, the lower social class has lower HRQOL. Except for education and income level, chronic disease may be the major factor to explain the difference in the health-related quality of life among social classes.

• Journal of Nutrition and Health
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• v.41 no.8
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• pp.742-753
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• 2008

The purpose of this study is to investigate risk factors of pre-hypertension and hypertension in rural residents. Nine hundred and ninety four subjects aged 40-70 yrs in Chungnam-do participated in this study. The subjects (n = 824) were classified into three groups of hypertensive, pre-hypertensive, and normotensive according to the Joint National Committee (JNC)-7 criteria. The weight, body mass index (BMI), waist-hip ratio (WHR), and serum total protein, albumin, BUN, and triglyceride (TG) were positively correlated with SBP and DBP. After adjusted by age, sex and BMI, the total protein, albumin and TG were significantly correlated with SBP and DBP (p < 0.01). There was no significant difference in eating habits according to the level of blood pressure. The serum albumin, creatinine, Glu-FBS, Glu-PP l20, and triglyceride were higher in both prehypertensive and hypertensive group than in the normotensive group. However, mean serum cholesterol was not different among three blood pressure groups. In this study, the common risk factors of pre-hypertension and hyper-tension were male, age of fifties, lower education level, ex-smoking, higher drinking frequency, higher BMI, body fat %, waist circumference, WHR, serum albumin and diabetes, even though the degree of risks in these variables were higher in the hypertensive group. The higher BUN was a risk factor of prehypertension, while the family history, prediabetes, serum total protein, Glu-PP l20 and higher alcohol drinking amount were the risk factors of hypertension. This result suggests that maintaining good health habit and normal range of blood parameters as well as controlling body weight have to be paid attention in order to prevent hypertention, and further reseasch on the relationship of blood pressure and BUN are needed.

• Journal of Biosystems Engineering
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• v.3 no.2
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• pp.35-61
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• 1978

To find out the power tiller's travel and tractive characteristics on the general slope land, the tractive p:nver transmitting system was divided into the internal an,~ external power transmission systems. The performance of power tiller's engine which is the initial unit of internal transmission system was tested. In addition, the mathematical model for the tractive force of driving wheel which is the initial unit of external transmission system, was derived by energy and force balance. An analytical solution of performed for tractive forces was determined by use of the model through the digital computer programme. To justify the reliability of the theoretical value, the draft force was measured by the strain gauge system on the general slope land and compared with theoretical values. The results of the analytical and experimental performance of power tiller on the field may be summarized as follows; (1) The mathematical equation of rolIing resistance was derived as $$Rh=\frac {W_z-AC \[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\] sin\theta_1}} {tan\phi \[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]+\frac{tan\theta_1}{1}$$ and angle of rolling resistance as $$\theta _1 - tan^1\[ \frac {2T(AcrS_0 - T)+\sqrt (T-AcrS_0)^2(2T)^2-4(T^2-W_2^2r^2)\times (T-AcrS_0)^2 W_z^2r^2S_0^2tan^2\phi} {2(T^2-W_z^2r^2)S_0tan\phi}\] $$and the equation of frft force was derived as$$P=(AC+Rtan\phi)\[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]cos\phi_1 \ulcorner \frac {W_z \ulcorner{AC\[ [1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]sin\phi_1 {tan\phi[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\]+ \frac {tan\phi_1} { 1} \ulcorner W_1sin\alpha $$The slip coefficient K in these equations was fitted to approximately 1. 5 on the level lands and 2 on the slope land. (2) The coefficient of rolling resistance Rn was increased with increasing slip percent 5 and did not influenced by the angle of slope land. The angle of rolling resistance Ol was increasing sinkage Z of driving wheel. The value of Ol was found to be within the limits of Ol =2\ulcorner "'16\ulcorner. (3) The vertical weight transfered to power tiller on general slope land can be estim ated by use of th~ derived equation: $$R_pz= \frac {\sum_{i=1}^{4}{W_i}} {l_T} { (l_T-l) cos\alpha cos\beta \ulcorner \bar(h) sin \alpha - W_1 cos\alpha cos\beta$$The vertical transfer weight $R_pz$ was decreased with increasing the angle of slope land. The ratio of weight difference of right and left driving wheel on slop eland,$\lambda= \frac { {W_L_Z} - {W_R_Z}} {W_Z} $, was increased from ,$\lambda$=0 to$\lambda$=0.4 with increasing the angle of side slope land ($\beta = 0^\circ~20^\circ) (4) In case of no draft resistance, the difference between the travelling velocities on the level and the slope land was very small to give 0.5m/sec, in which the travelling velocity on the general slope land was decreased in curvilinear trend as the draft load increased. The decreasing rate of travelling velocity by the increase of side slope angle was less than that by the increase of hill slope angle a, (5) Rate of side slip by the side slope angle was defined as $ S_r=\frac {S_s}{l_s} \times$ 100( %), and the rate of side slip of the low travelling velocity was larger than that of the high travelling velocity. (6) Draft forces of power tiller did not affect by the angular velocity of driving wheel, and maximum draft coefficient occurred at slip percent of S=60% and the maximum draft power efficiency occurred at slip percent of S=30%. The maximum draft coefficient occurred at slip percent of S=60% on the side slope land, and the draft coefficent was nearly constant regardless of the side slope angle on the hill slope land. The maximum draft coefficient occurred at slip perecent of S=65% and it was decreased with increasing hill slope angle $\alpha$. The maximum draft power efficiency occurred at S=30 % on the general slope land. Therefore, it would be reasonable to have the draft operation at slip percent of S=30% on the general slope land. (7) The portions of the power supplied by the engine of the power tiller which were used as the source of draft power were 46.7% on the concrete road, 26.7% on the level land, and 13~20%; on the general slope land ($\alpha = O~ 15^\circ ,\beta = 0 ~ 10^\circ$) , respectively. Therefore, it may be desirable to develope the new mechanism of the external pO'wer transmitting system for the general slope land to improved its performance.l slope land to improved its performance.

• Journal of Biosystems Engineering
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• v.3 no.2
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• pp.34-34
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• 1978

To find out the power tiller's travel and tractive characteristics on the general slope land, the tractive p:nver transmitting system was divided into the internal an,~ external power transmission systems. The performance of power tiller's engine which is the initial unit of internal transmission system was tested. In addition, the mathematical model for the tractive force of driving wheel which is the initial unit of external transmission system, was derived by energy and force balance. An analytical solution of performed for tractive forces was determined by use of the model through the digital computer programme. To justify the reliability of the theoretical value, the draft force was measured by the strain gauge system on the general slope land and compared with theoretical values. The results of the analytical and experimental performance of power tiller on the field may be summarized as follows; (1) The mathematical equation of rolIing resistance was derived as $$Rh=\frac {W_z-AC \[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\] sin\theta_1}} {tan\phi \[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]+\frac{tan\theta_1}{1}$$ and angle of rolling resistance as $$\theta _1 - tan^1\[ \frac {2T(AcrS_0 - T)+\sqrt (T-AcrS_0)^2(2T)^2-4(T^2-W_2^2r^2)\times (T-AcrS_0)^2 W_z^2r^2S_0^2tan^2\phi} {2(T^2-W_z^2r^2)S_0tan\phi}\] $$and the equation of frft force was derived as$$P=(AC+Rtan\phi)\[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]cos\phi_1 ? \frac {W_z ?{AC\[ [1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]sin\phi_1 {tan\phi[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\]+ \frac {tan\phi_1} { 1} ? W_1sin\alpha $$The slip coefficient K in these equations was fitted to approximately 1. 5 on the level lands and 2 on the slope land. (2) The coefficient of rolling resistance Rn was increased with increasing slip percent 5 and did not influenced by the angle of slope land. The angle of rolling resistance Ol was increasing sinkage Z of driving wheel. The value of Ol was found to be within the limits of Ol =2? "'16?. (3) The vertical weight transfered to power tiller on general slope land can be estim ated by use of th~ derived equation: $$R_pz= \frac {\sum_{i=1}^{4}{W_i}} {l_T} { (l_T-l) cos\alpha cos\beta ? \bar(h) sin \alpha - W_1 cos\alpha cos\beta$$The vertical transfer weight $R_pz$ was decreased with increasing the angle of slope land. The ratio of weight difference of right and left driving wheel on slop eland,$\lambda= \frac { {W_L_Z} - {W_R_Z}} {W_Z} $, was increased from ,$\lambda$=0 to$\lambda$=0.4 with increasing the angle of side slope land ($\beta = 0^\circ~20^\circ) (4) In case of no draft resistance, the difference between the travelling velocities on the level and the slope land was very small to give 0.5m/sec, in which the travelling velocity on the general slope land was decreased in curvilinear trend as the draft load increased. The decreasing rate of travelling velocity by the increase of side slope angle was less than that by the increase of hill slope angle a, (5) Rate of side slip by the side slope angle was defined as $ S_r=\frac {S_s}{l_s} \times$ 100( %), and the rate of side slip of the low travelling velocity was larger than that of the high travelling velocity. (6) Draft forces of power tiller did not affect by the angular velocity of driving wheel, and maximum draft coefficient occurred at slip percent of S=60% and the maximum draft power efficiency occurred at slip percent of S=30%. The maximum draft coefficient occurred at slip percent of S=60% on the side slope land, and the draft coefficent was nearly constant regardless of the side slope angle on the hill slope land. The maximum draft coefficient occurred at slip perecent of S=65% and it was decreased with increasing hill slope angle $\alpha$. The maximum draft power efficiency occurred at S=30 % on the general slope land. Therefore, it would be reasonable to have the draft operation at slip percent of S=30% on the general slope land. (7) The portions of the power supplied by the engine of the power tiller which were used as the source of draft power were 46.7% on the concrete road, 26.7% on the level land, and 13~20%; on the general slope land ($\alpha = O~ 15^\circ ,\beta = 0 ~ 10^\circ$) , respectively. Therefore, it may be desirable to develope the new mechanism of the external pO'wer transmitting system for the general slope land to improved its performance.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.498-507
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• 2006

The main objective of present study was to evaluate how seasonal rainfall influenced natural habitat conditions of 10 metric habitat variables along with ionic conditions and suspended solids in the Woopo Wetland during August 2002-July 2003. Largest spatial variabilities in total suspended solids (TSS) occurred during the summer monsoon and the inorganic suspended solids (ISS), expressed as a inorganic proportion of total solids, showed linearly increasing trend from the upstream to downstream. This phenomenon was mainly attributed to counter flow of turbid water from the main Nakdong-River. During the flooding, ISS : TSS ratio showed large increases (92%) in the downstream than the upstream (43%). For this reason, transparency declined (mean=0.13 m, range=0.08-0.21 m) largely in the downstream reach and thus, chlorophyll-a concentration showed low values (range: $4.2-8.6\;{\mu}g\;L^{-1}$), indicating a direct influence on primary productivity or algal growth by inorganic turbidity. In the 2nd survey, ISS averaged 4.0 mg $L^{-1}$ (3.3-4.8 mg $L^{-1}$), thus the ISS decreased by 14 fold, compared to the ISS in the 1st survey during the flooding, while organic suspended solids (OSS) values were greater than those of ISS, indicating a dominance of organic solids. This condition was similar to solid contents in the 3rd survey, but showed a large difference compared to the 4th survey during the growing season. Habitat health assessments, based on 10 metric habitat variables, showed that QHEI values were greatest in the growing season (May) than any other seasons and largest spatial variations occurred in the 2nd survey. Overall, dataset suggest that seasonal episodic flooding during the monsoon may largely contribute nutrient cycling and sediment contents in the Woopo Wetland and Topyung Stream.