• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3866-3873
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• 2023

In 4th^-generation storage rings, whether to operate the beam as round or flat is a critical question. A round beam has equal horizontal and vertical emittances, and is an efficient solution to reduce strong intra-beam scattering effects and lengthen the Touschek lifetimes, but a flat beam produces a brighter photon beam than a round beam. To provide both beams concurrently rather than bifurcating the beam time, this paper presents the exploitation of beam dynamics and the cutting-edge fast pulser that supports concurrent operation of round beam and flat beam.

• Journal of Medicine and Life Science
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• v.20 no.4
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• pp.172-177
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• 2023

This study assessed risk factors for blood transfusion after Cesarean section in patients with partial placenta previa. We retrospectively reviewed the medical records of 149 patients who underwent Cesarean sections for partial placenta previa between January 2010 and October 2021. Clinical characteristics were compared between the two groups: the blood transfusion group (n=22), defined as patients who received a blood transfusion during surgery or within 24 hours after surgery, and the non-blood transfusion group (n=127), which included other patients. Multivariable logistic regression analysis identified two risk factors independently associated with blood transfusion: antenatal hemorrhage (adjusted odds ratio [aOR], 16.283; 95% confidence interval [CI], 4.405-60.190; P<0.001) and preoperative hemoglobin (g/dL) (aOR, 0.427; 95% CI, 0.246-0.739; P=0.002). Thus, patients who are at risk for these two factors should be carefully managed with sufficient preparation for blood transfusion and anesthetic management.

• Journal of Korean Clinical Health Science
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• v.1 no.1
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• pp.1-7
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• 2013

Purpose. To analysis the prevalence of the myopia and corneal astigmatism in Korea women university students. Methods. From August 2011 to December 2012, one hundreds subjects were performed in refraction test using the Auto-Keratometry. Results. The mean age of the 100 subjects (200 eyes) was $21.23{\pm}2.34$. The mean spherical refractive power was -$1.78{\pm}1.65$(OD) and -$1.83{\pm}1.67$(OS) Diopter. The mean astigmatism power was $1.22{\pm}0.96$ (OD) and $1.27{\pm}0.91$ (OS). The mean corneal astigmatism was $1.44{\pm}0.81$(OD) and $1.55{\pm}0.93$(OS). Corneal astigmatism was between 0.25 D and 1.25 D in 67.7% of eyes, 1.25 D or higher in 27.5% eyes, and less than 0.25 D in 4.8% of eyes. Astigmatism was with the rule in 65%, against the rule in 31.5%, and oblique in 3.5%. There was a statistical significance between right eye and left eye in the spherical equivalent power(p=0.002). Also there was a statistical significance between spherical power and refractive astigmatism in OD(p=0.006) and OS(0.003) and a statistical significance between corneal astigmatism and refractive astigmatism in OS(p=0.0003). However, there was not a statistical significance between spherical power and corneal astigmatism in OD(p=0.08) and OS(0.1) and a statistical significance between corneal astigmatism and refractive astigmatism in OS(p=0.48). Conclusions. In this study, these results suggested that the analysis of the refractive myopia and corneal astigmatism can provide the visual correct and useful diagnosis information for the eyewear dispensing, contact lens fitting and corneal refraction surgery.

• Korean Journal of Digital Imaging in Medicine
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• v.14 no.1
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• pp.37-42
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• 2012

Pediatric head and neck phantom, using the rate by focusing distance and grid images, Image J using the Quality Assessment and Dose Area Product compared. X-ray laboratory equipment due to the Philips Digital DIAGNOST a 110 cm FFD set and using ACE Non-grid, focusing distance 110 cm (12 : 1), 140 cm (12 : 1), 180 cm (8 : 1) Focused grid, Acryl Phantom (Fluke Model 76-2 Series Phantom) 15.24 cm, by resolution chart image acquisition, image evaluation program (Image J Ver. 1.4.3.67, USA) imaging experiments were analyzed using. Dose Area Product in the Non Grid 0.028 $mGy{\cdot}cm^2$, focusing distance 110 cm (12 : 1), the 0.129 $mGy{\cdot}cm^2$, 140 cm (12 : 1), the 0.135 $mGy{\cdot}cm^2$, 180 cm (8 : 1) was measured with a 0.110 $mGy{\cdot}cm^2$ Non Grid, focusing distance 110 cm (12 : 1), 140 cm (12 : 1), 180 cm (8 : 1) Image obtained when grid using the image J program focusing distance 110 cm with grid based on the measured SNR and PSNR Non Grid if the SNR the 17.307 dB, PSNR of the 20.002 dB, if the SNR 28.755 dB, PSNR was measured by the 31.451 dB. Image J image analysis through the streets, rather than focusing on grid by the rate that could see an increase in dose. Select the grid by a small dose rate reduction is possible.

• Korean Journal of Radiology
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• v.21 no.12
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• pp.1374-1382
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• 2020

Objective: To determine whether ultrasonography at initial presentation can help assess the clinical severity of congenital muscular torticollis (CMT) in infants without a sternocleidomastoid muscle (SCM) mass. Materials and Methods: This retrospective study included 71 infants aged less than 12 months (4.1 ± 2.3 months) with non-mass CMT. The clinical severity was divided into three grades (groups 1-3) based on the degree of lateral head bending or cervical rotation. The difference (SCM-D) and ratio (SCM-R) between the maximal thickness of the affected and non-affected SCMs were obtained using transverse and longitudinal ultrasonography. The sonographic echotexture and echogenicity of the involved SCM were reviewed. Results: A significant difference was observed in the SCM-D (0.42 ± 0.30 mm in group 1; 0.74 ± 0.50 mm in group 2; 1.14 ± 0.85 mm in group 3; p = 0.002) and SCM-R (1.069 ± 0.067 in group 1; 1.129 ± 0.087 in group 2; 1.204 ± 0.150 in group 3; p = 0.001) among the groups when measured along the longitudinal but not along the transverse ultrasonography plane. The areas under the curves of the SCM-R and SCM-D measured by longitudinal ultrasonography were 0.731 (p < 0.001) and 0.731 (p < 0.001) for group 1 versus groups 2-3. The proportions of heterogeneous echotexture or hyperechogenicity in the involved SCM did not differ significantly among the three clinical groups (all p > 0.05). Conclusion: Ultrasonography can aid in assessing the clinical severity of CMT in infants without an SCM mass at the time of initial diagnosis. The SCM-R and SCM-D helped grade the clinical severity when obtained by longitudinal scan.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1873-1879
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• 2010

This study was conducted to estimate the heavy metal contents of vegetables available on the markets in Seoul area. Concentrations of mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), chrome (Cr), nickel (Ni), copper (Cu), and zinc (Zn) were measured in 300 samples using a mercury analyzer and inductively coupled plasma optical emission spectrometer (ICP-OES) after wet digestion. The average values of heavy metals in vegetables were as follows [mean (minimum~maximum), mg/kg]; Hg: 0.0005 (N.D~0.007), Pb: 0.011 (N.D~0.259), Cd: 0.012 (N.D~0.188), As: 0.002 (N.D~0.142), Cr: 0.100 (0.019~0.954), Ni: 0.093 (0.003~1.231), Cu: 1.098 (0.072~36.29), and Zn: 3.48 (0.485~21.31). The heavy metal contents of vegetables available on the markets in Seoul were almost the same as or lower than those reported in other studies. The weekly average intakes of mercury, lead and cadmium from vegetables take 0.44~7.71% of PTWI (Provisional Tolerable Weekly Intakes) that the FAO/WHO Joint Food Additive and Contaminants Committee sets for evaluation of food safety.

• Korean Security Journal
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• no.51
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• pp.103-124
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• 2017

The purpose of this study is to analyze regional clusters and discrimination on size and sector of private security in national 16 areas in 2015. The results of the study using hierarchical cluster analysis and discriminant analysis are as follows. First, we can classify national 16 areas into 3 clusters, such as Large Area(1), Medium Area(2), and Small Area(3) according to the size of private security. The discriminant functions D for each cluster is as follows: (1) Large Area(1) = -383.981 + (.108 ${\times}$ number of security companies) + (.016 ${\times}$ number of guards), (2) Medium Area(2) = -35.570 + (.029 ${\times}$ number of security companies) + (.005 ${\times}$ number of guards), and (3) Small Area(3) = -5.381 + (.012 ${\times}$ number of security companies) + (.002 ${\times}$ number of guards). Second, we can classify national 16 areas into 3 clusters, such as Large Area(1), Medium Area(2), and Small Area(3) according to the sector of private security. The discriminant function D for each cluster is as follows: (1) Large Area(1) = -2224.402 + (-.562 ${\times}$ facilities security) + (1.245 ${\times}$ protection security) + (171.142 ${\times}$ convoy security) + (-2.722 ${\times}$ electronic security) + (2.020 ${\times}$ special security), (2) Medium Area(2) = -4.762 + (.052 ${\times}$ facilities security) + (.063 ${\times}$ protection security) + (-3.819 ${\times}$ convoy security) + (.110 ${\times}$ electronic security) + (-.165 ${\times}$ special security), and (3) Small Area(3) = -125.742 + (-.009 ${\times}$ facilities security) + (.432 ${\times}$ protection security) + (5.748 ${\times}$ convoy security) + (5.530 ${\times}$ electronic security) + (-.901 ${\times}$ special security).

• Nuclear Engineering and Technology
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• v.18 no.3
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• pp.218-227
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• 1986

Studies were conducted to determine the extent of oxidation and same of the mechanical property changes of Zircaloy-4 fuel cladding after it was exposed to hot steam environment. The purpose of these tests was to provide some informations on the embrittlement behavior of CANDU type fuel cladding, which could be experienced under the loss-of-coolant accident conditions. The Zircaloy fuel cladding tubes were exposed in a steam environment at the temperature of 90$0^{\circ}C$, 1,00$0^{\circ}C$. The growth of the ZrO$_2$ layer combined with an oxygen rich $\alpha$-phase layer into the Zircaloy tube material was found as a function of time t and temperature of steam exposure, E=1.1√Dt+0.002 where D is a temperature dependent diffusion coefficient. The tensile strength of the specimens exposed for a short period increased but decreased continuously with further exposure. The circumferential elongation was drastically changed with the exposure time while the hoop strength did't decrease greatly. The X-ray measurement of preferred orientation of the Zircaloy tube material indicated that grains in the as received tube were oriented such that the poles of the basal (0001) planes were predominantly radial, while the poles of the basal plane in the tube materials heattreated at 1,00$0^{\circ}C$ were oriented tangentially. It appears that this reoriented texture may contribute to lessening the decrease of the hoop strength of the heat treated Zircaloy tube material.

• Korean Journal of Ecology and Environment
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• v.45 no.4
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• pp.392-402
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• 2012

In this study, to analyze the stream health using fish assemblage and make effective management, we conducted fish monitoring in the Hoeya River basin and neighboring streams. A total of 33 species classified into 12 families were collected from 29 sites in 2007. Dominant species was Zacco platypus (Relative abundance, RA: 24.8%), and subdominant species was Rhynchocypris oxycephalus (RA: 16.2%). Eight Korean endemic species and 4 exotic species were identified. Moreover, two species (Opsariichthys uncirostris amurensis and Hemiculter eigenmanni) were translocated from other basin. To evaluate stream health of the study sites, Index of Biological Integrity (IBI) was applied, based on fish assemblages. Overall, IBI values were "C (Fair)" or "D (Poor)" condition, according to the grade except two sites which recorded "B (Good)". The correlation between land use pattern of surrounding watershed and IBI was analyzed to verify impact of development on stream health using fish assemblage. As a result, when percentage of the developmental groups increased, IBI values were decreased (Pearson correlation, r=-0.425, p=0.022). In contrast, increment of percent forest and grass land was positively correlated with IBI (r=0.556, p=0.002). The agricultural group and IBI did not significantly correlate with each other (r=-0.231, p=0.333). In this study, we identified a relationship between land use of surrounding watershed and stream health using fish data (i.e. IBI). These results could be provided useful fundamental information to establish management and restoration plan in the Hoeya River basin and other rivers distributed in Korea.

• Korean Journal of Poultry Science
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• v.36 no.2
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• pp.157-163
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• 2009

This work was conducted to investigate the amount and major compositions of excreta from broilers. One hundred fifty 1-d-old male and female Ross broilers were used in this work and ten broilers were selected to measure excreta. Average amount of excreta per broiler was 85.4 g, and average moisture content was 76.9%. N, $P_2O_5$ and $K_2O$ in excreta were 1.19, 0.29 and 0.49%, respectively. pH, $BOD_5$, $COD_{mn}$, and SS were 7.80, 42,134 mg/L, 52,668 mg/L, and 106,669 mg/L, respectively. Pb in poultry excreta was 0.803 mg/kg and highly lowed compared with the standard contents (150 mg/kg). Cd was not founded in excreta. Hg was founded in excreta as 0.002 mg/kg, but it was low compared with the standard level (2 mg/kg).