• Journal of Powder Materials
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• v.24 no.3
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• pp.242-247
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• 2017

In this study, the electroless nickel plating method has been investigated for the coating of Ni nanoparticles onto fine Al powder as promising energetic materials. The adsorption of nickel nanoparticles onto the surface of Al powders has been studied by varying various process parameters, namely, the amounts of reducing agent, complexing agent, and pH-controller. The size of nickel nanoparticles synthesized in the process has been optimized to approximately 200 nm and they have been adsorbed on the Al powder. TGA results clearly show that the temperature at which oxidation of Al mainly occurs is lowered as the amount of Ni nanoparticles on the Al surface increases. Furthermore, the Ni-plated Al powders prepared for all conditions show improved exothermic reaction due to the self-propagating high-temperature synthesis (SHS) between Ni and Al. Therefore, Al powders fully coated by Ni nanoparticles show the highest exothermic reactivity: this demonstrates the efficiency of Ni coating in improving the energetic properties of Al powders.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.242-242
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• 2010

산화 알루미늄($Al_2O_3$) 박막을 p-type Czochralski(CZ) Si 위에 Remote Plasma Atomic Layer Deposition(RPALD)을 이용하여 저온 공정으로 증착하였다. Photolithography 공정으로 grid 패턴을 형성한 후 열 증착기로 알루미늄을 증착하여 MIS-IL (Metal-Insulator-Semiconductor Inversion Layer) solar cell을 제작하였다. 반응소스로는 Trimethylaluminum (TMA)과 $O_2$를 이용하였다. $Al_2O_3$ 박막의 전기적 특성 평가를 위해 MIS capacitor를 제작하여 Capacitance-voltage (C-V), Current-voltage (I-V), Interface state density ($D_{it}$)를 평가하였으며 Solar simulator를 이용하여 MIS-IL Solar cell의 Efficiency을 측정하였다.

• Textile Coloration and Finishing
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• v.26 no.3
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• pp.242-253
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• 2014

Morinda citrifolia, commercially known as Noni, is a tree that grows widely throughout the Pacific, and is recognized as one of the most significant sources of traditional medicines among Pacific Island societies. All parts of the plant have traditional and/or modern uses, including roots and bark(dyes, medicine), trunks(firewood, tools), and leaves and fruits(food, medicine). The bark and the roots of the tree contain red and yellow pigments respectively, which are both used in the manufacture of dyes. Dyes from Noni are being used traditionally, to color clothing and fabrics. In this study, mordanting effects on the dyeing properties of Noni root extract on silk fabrics were investigated.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.3
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• pp.242-248
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• 2019

Purpose: Severe acute malnutrition (SAM) is an important public health problem which contributes to significant number of under five deaths. Protocol based management significantly decreases risk of deaths in children with medical complications. Methods: Outcome of children aged 2 months-5 years admitted and fulfilling definition of SAM having diarrhea (group A) was compared to children with SAM having medical complications other than diarrhea (group B). Both groups were managed according to standard recommended protocols and monitored and followed up for 12 weeks after discharge. Results: The average weight gain, defaulter rate, primary failure, secondary relapse rate and readmission rate were similar in both groups. Length of stay in group A was three days longer (p-value=0.039). Discharge rate was comparable with overall 68% of children successfully discharged and 50% of children reaching weight/height > -2 standard deviation at follow-up of 12 weeks. Conclusion: The current management protocol is equally effective for managing children with SAM having diarrhea. Good adherence to management protocol of dehydration and timely modification of therapeutic feeds in children with persistent diarrhea results in satisfactory weight gain.

• The Journal of Korean Physical Therapy
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• v.34 no.5
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• pp.242-247
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• 2022

Purpose: This study investigates the effect of 60° semi-squat exercises according to three different types of support surfaces. The effects were examined on joint position sense and balancing ability using stable and unstable surfaces in patients afflicted with post-stroke hemiplegia. Methods: Subjects were instructed to perform three sets of 60° semi-squat exercises according to the characteristics of the support surface conditions. The three ground states were bilateral stable surface (BSS), nonaffected side unstable surface (NUS), and bilateral unstable surface (BUS). The joint position sense, characteristics of body sway, and dynamic balance were analyzed according to floor conditions before and after the experiment. A balance-pad (50 cm W×41 cm L×6 cm H; Alcan Airex AG, Sins, Switzerland) was used for the unstable floor. Results: The 60° semi-squat exercises applied to hemiplegic patients showed the highest statistical significance in joint position sense in the NUS group, and Timed Up and Go test (TUG) in the BUS group (p<0.05). Conclusion: Functional training using an unstable surface can be applied as a meaningful intervention method for improving the balance and joint position sense of stroke patients.

• Korean Journal of Ecology and Environment
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• v.56 no.3
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• pp.242-249
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• 2023

The aquarium pet trade is a source of potentially invasive crayfish species, which can be subsequently intentionally or unintentionally introduced into new environments. There were 34 species of freshwater crayfish imported into Korea for ornamental purposes. Starting with 1 species in 2008, it shows a trend of continuous increase every year with the maximum of 25 species in 2020. The number of freshwater crayfish imported into Korea for ornamental purposes was 1,172,159, with an annual average of 78,144 being imported. The population also recorded a record high in 2017 with a 38% increase in population imports compared to the previous year. Among the 34 pet crayfish imported into Korea, four species classified as high-risk and managed in the US and Europe were American crayfish (Procambarus clarkii), Cherax quadricarinatus, Cherax cainii, and Cherax destructor. In addition to American crayfish (P. clarkii), 3 types of high-risk invasive crayfish are designated as legally managed species by conducting an ecological risk assessment, raising awareness among importers, retailers and consumers through awareness-raising education on freshwater crayfish, and measures for route management such as species identification and improvement of labeling methods are needed.

• Health Communication
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• v.13 no.2
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• pp.141-148
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• 2018

Background: The purpose of this study is to identify the degree of emotional labor, mental health care, care performance of certified caregivers for elder with dementia, and the factors that affect care performance. Methods: In order to collect data, structured questionnaire was used for 197 caregivers who worked at 3 dementia specialized facilities located in D city. Data were analyzed by t-test, ANOVA, correlation and multiple regression using SPSS/WIN 20.0. Results: Care performance had negative relationship with emotional labor(r=-.320, p<.000) and mental health(r=-.240, p<=001). Emotional labor had positive relationship with mental health(r=.208, p=.003) And the prediction factors influencing care performance were health status(${\beta}=.363$, p<.001), emotional labor(${\beta}=-.242$, p<.001), mental health(${\beta}=-.223$, p=.001). The total variance was 38.9% by predictors(F=25.978, p<.001). Conclusion: Based on the results of this study, in order to improve the care performance mental health program should be provided and good health management is needed to improve health status. And also it is necessary to develop and apply new strategies to reduce emotional labor of the dementia facility caregivers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.500-506
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• 2018

This study analyzed current prehospital emergency care for severe trauma patients administered by different number of 119 EMS (emergency medical services) teams. Out of 1,067 severe trauma patients transferred by 119 EMS teams in J province from January 1st to December 31st 2015, 438 were evaluated in this study. IBM SPSS Statistics 21.0 was used to analyze collected data. The number of patients with severe trauma during the period of study was higher in male with two and three ambulance crews of 119 EMS teams with 242 patients (70.6%) and 66 patients (69.5%) respectively. The percentage of transfers made to local emergency medical centers was highest in those two groups, being 44.0% (151 patients) and 49.5% (47 patients), respectively. Total time spent at the scene did not differ between ambulance crews of two and three, nor did the frequency of practicing advanced airway management and IV (intravenous) cannulation, or the success rate of IV cannulation (p=0.253, p=0.362, p=1.000). Overall, the results indicated that merely increasing the number of paramedics does not improve the quality of prehospital care for severe trauma patients. Measures such as securing professional paramedics, simplifying direct medical oversights, activating indirect medical oversights, and expanding the legally allowed work scope are required.

• Journal of the Mineralogical Society of Korea
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• v.18 no.1
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• pp.1-9
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• 2005

The electrocatalytic reduction of O₂ was investigated with methyl viologen and methylene blue incorporated clay-modified electrodes. Clay suspensions were prepared with Na-montmorillonite, Ca-montmorillonite, and kaolinite. The methyl viologen-clay modified electrodes were made by coating clay suspensions adsorbing methyl viologen on a glassy carbon electrode. Cyclic voltammetry were performed in aqueous media to investigate the electrocatalytic property of the modified electrode in reducing O₂. A Na-montmorillonite modified electrode showed the greatest adsorption capacity for methyl viologen. The modified electrode made of Na-montmorillonite suspension of 0.87 g/10 mL and a 2.5 mM of methyl viologen solution showed the most effective electrocatalytic property, where the catalytic reduction potential was shifted by 242.6 mV toward the positive potential. The electrocatalytic ability was more significant in acidic (pH=3.7) and alkaline (pH=12.7) media than the neutral pH range (6.3∼8.3). The methyl viologen-Na-montmorillonite modified electrode had the good reproducibility and maintain the electrocatalytic property over 20 times reuse.

• Analytical Science and Technology
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• v.11 no.4
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• pp.235-242
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• 1998

Membrane electrode based on chitin(po1y-[$1{\rightarrow}4$]-${\beta}$-N-acetyl-D-glucosamine) was prepared by mixing uniformly grounded of chitin (100 mesh) with PVC and DOS. We investigated the potential response of chitin membrane electrode to metal ions. It was observed that the response slopes for $Cd^{2+}$(34.9 mV/decade) and $Cu^{2+}$(34.0 mV/decade) were larger than those for other ions in pH 4 acetate buffer. The potentiometric response of chitin electrode to varying pH was nearly constant in the pH range of 2~12.