• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.708-715
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• 2016

This study examined the effects of an extract of Dendropanax morbifera on blood pressure, Angiotensin II, Angiotensin Converting Enzyme, Aldosterone, and lipid levels of spontaneously hypertensive rats. The groups were as follows: Control group, Hypertension control group, Water extract treated group, Ethanol extract treated group, n- hexane fraction treated group, Ethyl acetate fraction treated group, n- butanol fraction treated group, and Water fraction treated group. The blood pressure, and Angiotensin II, and Angiotensin Converting Enzyme, and Aldosterone levels were lower in the Ethyl acetate fraction treated group than in the hypertension control group. The change in blood pressure was lower in the Water extract treated group, Ethyl acetate fraction treated group, Ethanol extract treated group, n- hexane fraction treated group, and n- butanol fraction treated group than the hypertension control group. The concentration of Angiotensin II was lower in the Ethyl acetate fraction treated group, Ethanol extract treated group, n- hexane fraction treated group, and n- butanol fraction treated group than the hypertension control group(p<0.05). The level of Angiotensin Converting Enzyme was lower in the Ethyl acetate fraction treated group, Ethanol extract treated group, n- hexane fraction treated group, and n- butanol fraction treated group than the hypertension control group. The concentration of Aldosterone was lower in the Ethyl acetate fraction treated group, and n- butanol fraction treated group than the hypertension control group(p<0.05). In addition, the concentration lower in the Water extract treated group, Ethanol extract treated group, n- hexane fraction treated group than the hypertension control group. Overall, the effect of the Dendropanax morbifera extracts might be useful as anti-hypertensive, and functional food agents.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.104-111
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• 2016

This study examined the effects of the biological markers and lifestyle factors on the presence of diabetes in middle-aged adults. A total of 5,363 adults aged 40-64 years were recruited from the 2010-2012 Fifth Korean National Health and Nutrition Examination Survey. The data were analyzed by descriptive statistics, Chi-square test, ANCOVA and logistic regression. The results were as follows. The body mass index was significantly higher in the prediabetes and diabetes group than in the normal group. Hypertension, abdominal obesity, hypercholesterolemia, hypertriglyceridemia, smoking, drinking, and carbohydrate intake were significantly different among three groups. Hypertension, hypercholesterolemia, hypertriglyceridemia, abdominal obesity, body mass index and drinking were the influencing biological markers and lifestyle factors in prediabetes. The significant factors influencing diabetes were hypertension, hypercholesterolemia, hypertriglyceridemia, abdominal obesity, body mass index, and smoking. Overall, the development of intervention programs for effective diabetes prevention in middle-aged adults by lifestyle modification of hypertension, obesity, dyslipidemia, drinking, and smoking is recommended.

• Korean Journal of Optics and Photonics
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• v.31 no.3
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• pp.142-147
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• 2020

In this paper, we report highly efficient second harmonic generation of continuous-wave Yb fiber lasers incorporating a periodically poled LiTaO₃ device (MgO:PPSLT) as a frequency converter. The seed laser output from a Yb fiber master oscillator using a Fabry-Perot feedback cavity was amplified in a Yb fiber amplifier stage, yielding 28.5 W of linearly polarized output at 1064 nm in a beam with beam quality, M², of ~1.07. Second harmonic generation was achieved by passing the laser beam through MgO:PPSLT. Under optimized conditions, we obtained 11.1 W of green laser output at 532 nm for an incident signal power of 25.0 W at 1064 nm, corresponding to a conversion efficiency of 44.4%. The detailed investigation to find the optimized operating conditions and prospects for further improvement are discussed.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.1
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• pp.57-63
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• 2019

Hypertension is caused by a combination of genetic and environmental factors. In advanced countries, more than 30% of adults have hypertension. Among the genetic factors affecting hypertension, there are reports from European cohort studies that variants of the MACROD2 gene are correlated with blood pressure and the hypertension status. In this study, genetic polymorphisms of the MACROD2 gene region were selected and extracted based on Korean Genome and Epidemiology data, and logistic regression analysis was then performed for the hypertensive state. Linear regression analysis was also performed for the systolic and diastolic blood pressure. As a result, 16 SNPs showed a statistically significant association with a hypertensive state, and 2 SNPs (rs16996211, rs6034240) showed statistical significance, even in blood pressure. The most significant rs16996211 had a relative risk of hypertension of 0.85 (CI: 0.76~0.95, $P=3.1{\times}10^{-3}$), as well as an association with the systolic blood pressure (beta=-0.75, P=0.024) and diastolic blood pressure (beta=-0.59, P=0.01). These results suggest that polymorphisms of the MACROD2 gene are associated with hypertension in both Caucasians and Koreans, and highlight the potential genetic correlations with the pathogenesis of hypertension.

• Korean Journal of Heritage: History & Science
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• v.48 no.4
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• pp.94-109
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• 2015

This study examines Korea's revitalization policy on the ancient capital cities, which has been set out for preserving and improving living quality of the local communities. Since it was established, the policy has faced with constant challenges such as the lack of funding for preservation and revitalization of local communities. This study aims at providing a set of recommendation on the problems on the policy. In order for the study, it takes objective and empirical analysis on the problems of the policy by executing survey on the satisfaction level of the stakeholders and policy-makers on the present policy. The survey has displayed that the government needs to 1. subsidize more budget, 2. set out a policy to reduce the inconvenience of local communities 3. establish a supportive program to help the present promotion policy. In addition, the survey analysis has proved that the elements of revitalization policy affect to the increase of satisfaction. It concludes with a set of recommendation, 1. to secure sufficient budget to implement the policy; 2. to reduce a restriction of individual rights; 3. to promote the supporting program of local community; 4. to establish governance system with officers, experts, residents, and research institutes.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.671-684
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• 2022

This study verified the stability of a high-strength combined buried pile retaining wall and its applicability in the field. A cast-in-place (C.I.P) retaining wall and the high-strength combined embedded pile retaining wall were compared and analyzed numerically. The numerical analysis assessed the ground behavior and stability (and thus field applicability) of a high-strength combined buried pile retaining wall using data measured in the field. The experimental results showed that the cross-sectional force and displacement of the high-strength bonded pile retaining wall were reduced by 13.6~19.7%, the shear force increased by 0.7~4.7%, and the bending moment increased by 4.5~8.8% relative to the values for the C.I.P retaining wall. Examination of the amount of subsidence in the ground around the excavation showed that the maximum settlement of the C.I.P retaining wall was 46.89 mm and that at the high-strength combined buried pile retaining wall was 39.37 mm. Overall, designing a high-strength combined embedded pile retaining wall by applying the maximum bending moment and shear force calculated using the elastic beam method to the site ground was shown to achieve the safety of all members, as member forces were generated within the elastic region.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.4
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• pp.222-230
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• 2023

In the present work, the scale effect on the Boil-Off Rate (BOR) was investigated based on an analytical method to systematically evaluate the thermal performance of a Liquefied Natural Gas (LNG) Cargo Containment System (CCS). A two-dimensional thermal resistance network model was developed to accurately estimate the heat ingress into the CCS from the outside. The analysis was performed for the KC-1 LNG membrane tank under the IGC and USCG design conditions. The ballast compartment of both the LNG tank and cofferdam was divided into six sections and a thermal resistance network model was made for each section. To check the validity of the developed model, the analysis results were compared with those from existing literature. It was shown that the BOR values under the IGC and USCG design conditions were agreed well with previous numerical results with a maximum error of 1.03% and 0.60%, respectively. A SDR, the scale factor of the LNG CCS was introduced and the BOR, air temperature of the ballast compartment, and the surface temperature of the inner hull were obtained to examine the influence of the SDR on the thermal performance. Finally, a correlation for the BOR was proposed, which could be expressed as a simple formula inversely proportional to the SDR. The proposed correlation could be utilized for predicting the BOR of a full-scale LNG tank based on the BOR measurement data of lab-scale model tanks.

• Journal of the Korean Society of Radiology
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• v.84 no.5
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• pp.1009-1016
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• 2023

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. In Korea, RFA for thyroid nodules was first performed in 2002, and a large population study was published in 2008. The Task Force Committee of the Korean Society of Thyroid Radiology (KSThR) developed its first recommendations for RFA in 2009, which were revised in 2012 and 2018. The KSThR guideline was the first guideline for RFA of thyroid nodules worldwide and has become a guideline for physicians to perform thyroid RFA in Korea and other countries around the world. These guidelines have contributed significantly to the establishment and widespread use of RFA worldwide. In addition, since 2015, the KSThR has conducted intensive hands-on courses depending on the level of the participants. In this article, the authors introduce the history of eduction for RFA conducted by the KSThR and describe the learning curve of RFA and current training programs in Korea, along with future directions for training programs.

• Childhood Kidney Diseases
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• v.11 no.2
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• pp.168-177
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• 2007

Purpose : The purpose of this study was to investigate whether hypercalciuria patients with hematuria show different renal indices compared to non-hypercalciuria patients with hematuria. Methods : We retrospectively reviewed the medical records of patients with gross or microscopic hematuria whose blood chemistry and 24 hour urine chemistry were examined. After excluding the patients with more than $4 mg/m^2/day$ proteinuria or the patients with urinary calcium excretion between 3 and 4 mg/kg/day, we divided the patients into two groups: a hypercalciuria group whose calcium excretion was more than 4 mg/kg/day(n=30) and a non hypercalciuria group whose calcium excretion was less than 3 mg/kg/day(n=41). The urinary excretion, clearance, and fractional excretion(FE) of Na, K, Cl, Ca, P, urea, and creatinine were calculated and compared between the two groups. Results : The hypercalciuria group had more calcium excretion($6.1{\pm}2.9$ vs $1.5{\pm}0.9 mg/kg/day$), more urea excretion($341{\pm}102$ vs $233{\pm}123 mg/kg/day$), greater glomerular filtration rate(GFR) ($93.7{\pm}31.1$ vs $79.5{\pm}32.0 mL/min$) but lower FENa($1.0{\pm}0.4%$ vs $1.3{\pm}0.6%$) than the nonhyper-calciuria group, although the urinary sodium excretion was similar between the two groups. Conclusion : The greater urea excretion and GFR in hypercalciuric patients suggest that they might be on a higher protein diet than the non-hypercalciuria group. The increased glomerular filtration of sodium and calcium induced by the higher GFR in hypercalciuria would have increased their delivery to the distal tubule, where sodium is effectively reabsorbed but calcium is not, which is suggested by the lower FENa but higher FECa in hyercalciuria. It is recommended that the diet of hematuria patients be reviewed in detail at initial presentation and during treatment.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.1
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• pp.105-109
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• 2015

This paper presents the results of an experimental analysis of the high-power laser (HPL)-induced damage to a complementary metal-oxide semiconductor (CMOS) image sensor. Although the laser-induced damages to metallic materials have been sufficiently investigated, the damages to electric-optic imaging systems, which are very sensitive to HPLs, have not been studied in detail. In this study, we experimentally analyzed the HPL-induced damages to a CMOS image sensor. A near-infrared continuous-wave (CW) fiber laser was used as the laser source. The influences of the irradiance and irradiation time on the permanent damages to a CMOS image sensor, such as the color error and breakdown, were investigated. The experimental results showed that the color error occurred first, and then the breakdown occurred with an increase in the irradiance and irradiation time. In particular, these damages were more affected by the irradiance than the irradiation time.