• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.5
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• pp.216-220
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• 2010

Ni-Fe alloys have various applications such as thin film inductor, thin film transformer, magnetic head's shield case, etc. Magnetic properties of Ni-Fe thin films depend on the process parameters such as thickness, contents, deposition rate, substrates, etc. In this study, NiFe films with a thickness of about 150nm were deposited on Si(100) wafer and $SiO_2$/Si(100) substrate at room temperature by a DC magnetron co-sputtering using Fe and Ni targets. Their phase formation and magnetic properties as a function of annealing temperature were investigated with XRD, FE-SEM and VSM. The assputtered films have BCC structure. With increasing annealing temperature, NiFe thin film for $SiO_2$/Si(100) substrate transformed completely from BCC to FCC phase above $500^{\circ}C$, but some BCC phase remained above $500^{\circ}C$ on Si(100) wafer. For samples annealed at $450^{\circ}C$, squareness ratio of NiFe thin film shows peak value and its saturation magnetization is around 0.0118 emu, which means that the optimum annealing temperature of NiFe thin film seems to be $450^{\circ}C$. The saturation magnetization of films decreased rapidly above the annealing temperature of $500^{\circ}C$ due to phase transformation from BCC to FCC phase.

• Korean Journal of Plant Resources
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• v.24 no.4
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• pp.379-394
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• 2011

This study was carried out to classify the folk plants in southern region of Gangwon-do. According to the survey results from 1,103 survey sheets of 83 residents at 32 places of 9 counties and cities from March to October, 2010, the folk plants in the southern region of Gangwon-do consisted of a total 311 taxa; 92 families, 222 genera, 274 species, 2 subspecies, 29 varieties, and 6 form. The use by its usage was: 227 taxa; Edible, 174 taxa; Medicinal, 14 taxa; Ornamental, 5 taxa; Oil, 5 taxa; Spice, 4 taxa; Dye, 1 taxa; Fiber, 1 taxa; Aroma, 1 taxa; Fuel, 32 taxa; Others, respectively, so the edible use is the highest. The most useful part was the leaf, followed by root and fruit. The consistency comparison between the scientific name and the local name were the highest in the 50's and the lowest in 80's.

• Resources Recycling
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• v.25 no.5
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• pp.75-83
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• 2016

AlN powder was prepared by carbon reduction and subsequent nitridation method through the scale-up experiments of 0.7 ~ 1.5 kg per batch. AlN powder was synthesized using the mixture of $Al_2O_3$ powder and carbon black at $1,550{\sim}1,750^{\circ}C$ for 0.5 ~ 4 hours under nitrogen atmosphere (flow rate of nitrogen gas: $10{\sim}40{\ell}/min$) at $2.0{\times}10^{-1}Torr$. Experimental results showed that $1,700{\sim}1,750^{\circ}C$ for the reaction temperature, 3 hr for reaction time, and $40{\ell}/min$ for the flow rate of nitrogen gas were the optimal conditions. Also, in order to remove carbon in the synthesized AlN, the remained carbon was removed at $650{\sim}750^{\circ}C$ for 1 ~ 2 hr using horizontal tube furnace. The results showed that 1 : 3.2 mol ratio of $Al_2O_3$ to carbon black, reaction temperature of $750^{\circ}C$, reaction time of 2 hours, rotating speed of 1.5 rpm under atmosphere condition were the optimal conditions. Under these conditions, high-purity AlN powder over 99% could be prepared: carbon and oxygen contents of the AlN powder were 835 ppm and 0.77%, respectively.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.731-732
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• 2007

This paper presents the final configuration of test field and test items for the application of IEC 60364-4-44 in Korea. IEC 60364-4-44 provides rules for the protection against the effects of conducted and radiated disturbances on electrical installations. Especially this standard deals with the protection of low voltage facility against the ground fault in the high voltage side of power distribution system. Many countries define the regulations on the use of electrical facilities based on their own power system and technical references which are considered to be suitable for them. The background of circuit of IEC 60364-4-44 is based on the ungrounded system as most of European countries. However, domestic electric power distribution system is based on multi-grounding system different from European system. Therefore, it is necessary to evaluate or prove the effect of the IEC 60364-4-44 for introducing and applying it to the domestic grounding system as a national standard. The authors with KEA(Korea Electric Association) carried out a project on the application of IEC 60364-4-44 to Korean electrical installations of buildings sponsored by Korean ministry of commerce, industry and energy for three years(2004.4.1$\sim$2007.3.31). The test field is established in K.E.R.I.(Korea Electrotechnology Research Institute), which is the purpose of evaluating the formula to calculate touch voltage and stress voltage in the IEC standards. This paper presents some considerations and final configuration of test field to evaluate and introduce the IEC 60364-4-44 applicable to domestic rule for the protection against ground fault.

• Korean Journal of Pharmacognosy
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• v.46 no.2
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• pp.148-153
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• 2015

Allium hookeri is a plant species native to India, Sri Lanka, Myanmar, and China. The plant is widely cultivated in Korea lately as a medicinal food item. This study was conducted to evaluate the effects of Allium hookeri (A. hookeri) on lipid metabolism in Type II diabetic mice (n=8/group, 5 groups). High fat diets with dextrin as a positive control (Dex), leaf (AL), root (AR), and fermented root (FAR) at 3% of diet were fed to all experimental mouse, respectively for 8 weeks. Body weight gain, liver and epididymal fat weights, and excreted fecal lipid levels were measured. Serum and hepatic lipid profiles were analyzed, and fat accumulation in liver was evaluated. In this study, body weight gain and epididymal fat weight were lower in the FAR group, while serum HDL-cholesterol level and excreted fecal total lipid and triglyceride levels were higher in AL or FAR groups. These results suggest that A. hookeri, specially fermented root can be a useful food item to control lipid metabolism in diabetic mice.

• Journal of Preventive Medicine and Public Health
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• v.29 no.4 s.55
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• pp.863-875
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• 1996

In order to prepare the fundamental data for the health promotion by assessing the exposure level of styrene, the author determined the concentration of mandelic acid and phenylglyoxylic acid in urine of 42 workers who were exposed to styrene by high performance liquid chromatography and surveyed 16 symptoms, by questionnaire and also tested neurobehavioral test(digit symbol, benton visual retention) in 2 FRP plants of Kyung Nam area from July to September, 1995. Control was sampled by age sex matching method. The concentration of styrene in air was determined by gas chromatography. The results were as follows; 1. Geometric mean concentration of styrene in air was 17.4ppm, geometric mean concentration of mandelic acid(MA) in urine were 404.3mg/g creatinine for exposure group, 46.4mg/g creatinine for control group, geometric mean concentration of phenylglyoxylic acid(PGA) in urine were 57.5mg/g creatinine for exposure group, 9.5mg/g creatinine for control group. Mean concentration of MA and PGA showed statistically significant difference between exposure group and control group(p<0.01). 2. Number of symptom were 2.9 for exposure group, 3.3 for control group, number of digit symbol were 24.1 for exposure group, 32.5 for control group, number of Benton visual retention test were 6.1 for exposure group, 6.0 for control group, respectively. As result of adjusting the education year, number of Benton visual retention test showed statistically significant difference between exposure group and control group(p<0.05). 3. Excellent correlation were observed between environmental styrene exposure and urinary MA(r=0.80), PGA(r=0.73), and MA+PGA(r=0.81).

• Journal of KIISE:Computer Systems and Theory
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• v.28 no.9
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• pp.415-423
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• 2001

Recently, there are many attempts to reproduce real world fine art pieces in digital forms. The digital representations are convenient to store and/or transmit. In contrast, mobiles, or moving sculptures, such as those designed by Alexander Calder cannot to reproduced realistically by usual reproduction techniques. Since mobiles are originally designed to generate motions in response to external forces applied to it, people could not fully enjoy them through photographs or static images. We present a virtual mobile system where use can easily control the mobile and can feel the impressions that the artist originally intended to provide. A real-world mobile is reconstructed in a three-dimensional physically-based model. and then virtual wind is generated to give motions to it. The motions of the mobile are generated by constraint dynamics and impulse dynamics techniques, which are modified to fully utilize the characteristics of the mobile, and finally give interactive displays on the PC platforms. The techniques presented can easily be extended to simulate other interactive dynamics systems.

• Korean Journal of Psychosomatic Medicine
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• v.24 no.1
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• pp.109-116
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• 2016

Objectives : This study aimed to investigate the effects of resilience on posttraumatic stress symptoms and dissociation and whether depression mediates the relationships between resilience and posttraumatic stress symptoms and dissociation. Methods : A total of 115 firefighters participated in the study. Data were collected via the Life Events Checklist, Impact of Event Scale-Revised, Dissociative Experience Scale, Beck Depression Inventory, and Connor-Davidson Resilience Scale. Structural equation modeling and path analysis were applied to estimate the relationships between resilience, depression, posttraumatic stress symptoms, and dissociation. Results : Greater resilience was associated with lower posttraumatic stress symptoms and dissociation, and the relationship between them was fully mediated by depression. Conclusions : Specific aspects of depression may help explain the relationships between resilience and posttraumatic stress symptoms and dissociation. Tailored prevention programs and treatments based on resilience and depression may prevent posttraumatic stress symptoms and dissociation in firefighters and improve treatments outcomes among firefighters with posttraumatic stress symptoms and/or dissociation.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.245-251
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• 2021

Codonopsis lanceolata (Deoduk) was grown in East Asia, including Korea, China, Japan, and Russia, and the roots of C. lanceolata have been used as functional foods and traditional medicine to treat symptoms of cough, bronchitis, asthma, tuberculosis, and dyspepsia. The phytochemicals of C. lanceolata have been reported such as phenylpropanoids, polyacetylenes, saponins, and flavonoids that are involved in pharmacological effects such as anti-obesity, anti-inflammation, anti-tumor, anti-oxidant, and anti-microbial activities. Selecting marker substances of the main producing area by MS-based metabolomics analysis is important to ensure the beneficial effect of C. lanceolata without side-effects because differences in cultivated areas of plants were related not only to the safety of medicinal plants but also to changes in chemical composition and biological efficacy. In our present study, ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry combined with multivariate statistical analysis was applied to recognize the main producing area of C. lanceolata in South Korea. As a result of Principal Component Analysis and loading plot analysis of three groups, Inje (Kangwon-do), Hoengseong (Kangwon-do), and Muju (Jeonlabuk-do), several secondary metabolites of C. lanceolata including tangshenoside I, lancemaside A, and lancemaside G, were suggested as potential marker substances to distinguish the place of main producing area of C. lanceolata.

• Journal of Neurogastroenterology and Motility
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• v.24 no.4
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• pp.603-613
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• 2018

Background/Aims Functional dyspepsia (FD) is one of the most common gastrointestinal disorders, and FD imposes social and economic burden worldwide. The aim of this study is to identify the prevalence and risk factors of FD in health check-up population in tertiary centers in Korea. Methods A nationwide multicenter prospective study was performed at 9 tertiary healthcare centers in Korea between September 2016 and June 2017. A total of 2525 subjects were investigated based on endoscopic findings and questionnaires with the Rome III criteria, and Helicobacter pylori serology (IgG). Results A total of 1714 subjects without organic disease were enrolled. The mean (${\pm}SD$) age was 51.5 (${\pm}12.7$) years, and 917 patients (53.5%) were female. The proportion of H. pylori seropositivity was 51.0% (874/1714). The prevalence of FD was 10.3% (176/1714), and the subtypes of postprandial distress syndrome alone, epigastric pain syndrome alone, and postprandial distress syndromeepigastric pain syndrome overlap were 4.8%, 3.0%, and 2.5%, respectively. Multivariate analysis showed that female gender (OR, 1.58; 95% CI, 1.14-2.21) and education below college level (OR, 1.45; 95% CI, 1.01-2.07) were related to FD. Multivariate analysis based on age 60 showed female gender as a significant (OR, 2.90; 95% CI, 1.06-7.94) factor in the group ${\geq}60$ years. Conclusions The prevalence of FD was 10.3% in the health check-up population in Korea. Female sex and education below college level were risk factors for FD. Female sex is a risk factor for FD in old age, underscoring the need for close attention in this age group.