• Title/Summary/Keyword: functional effect

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Effect of B-Cation Doping on Oxygen Vacancy Formation and Migration in LaBO3: A Density Functional Theory Study

  • Kwon, Hyunguk;Park, Jinwoo;Kim, Byung-Kook;Han, Jeong Woo
    • Journal of the Korean Ceramic Society
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    • v.52 no.5
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    • pp.331-337
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    • 2015
  • $LaBO_3$ (B = Cr, Mn, Fe, Co, and Ni) perovskites, the most common perovskite-type mixed ionic-electronic conductors (MIECs), are promising candidates for intermediate-temperature solid oxide fuel cell (IT-SOFC) cathodes. The catalytic activity on MIEC-based cathodes is closely related to the bulk ionic conductivity. Doping B-site cations with other metals may be one way to enhance the ionic conductivity, which would also be sensitively influenced by the chemical composition of the dopants. Here, using density functional theory (DFT) calculations, we quantitatively assess the activation energies of bulk oxide ion diffusion in $LaBO_3$ perovskites with a wide range of combinations of B-site cations by calculating the oxygen vacancy formation and migration energies. Our results show that bulk oxide ion diffusion dominantly depends on oxygen vacancy formation energy rather than on the migration energy. As a result, we suggest that the late transition metal-based perovskites have relatively low oxygen vacancy formation energies, and thereby exhibit low activation energy barriers. Our results will provide useful insight into the design of new cathode materials with better performance.

Musculotendon Model to Represent Characteristics of Muscle Fatigue due to Functional Electrical Stimulation (기능적 전기자극에 의한 근육피로의 특성을 표현하는 근육 모델)

  • Lim, Jong-Kwang;Nam, Moon-Hyon
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.8
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    • pp.1046-1053
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    • 1999
  • The musculotendon model is presented to show the declines in muscle force and shortening velocity during muscle fatigue due to the repeated functional electrical stimulation (FES). It consists of the nonlinear activation and contraction dynamics including physiological concepts of muscle fatigue. The activation dynamics represents $Ca^{2+}$ binding and unbinding mechanism with troponins of cross-bridges in sarcoplasm. It has the constant binding rate or activation time constant and two step nonlinear unbinding rate or inactivation time constant. The contraction dynamics is the modified Hill type model to represent muscle force - length and muscle force - velocity relations. A muscle fatigue profile as a function of the intracellular acidification, pH is applied into the contraction dynamics to represent the force decline. The computer simulation shows that muscle force and shortening velocity decline in stimulation time. And we validate the model. The model can predicts the proper muscle force without changing its parameters even when existing the estimation errors of the optimal fiber length. The change in the estimate of the optimal fiber length has an effect only on muscle time constant in transient period not on the tetanic force in the steady-state and relaxation periods.

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Electrodeposition and characterization of Ni-W-Si3N4 alloy composite coatings

  • Choi, Jinhyuk;Gyawali, Gobinda;Lee, Soo Wohn
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2015.05a
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    • pp.171-172
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    • 2015
  • $Ni-W-Si_3N_4$ alloy composite coatings were prepared by pulse electro-deposition method using nickel sulfate bath with different contents of tungsten source, $Na_2WO_4.2H_2O$, and dispersed $Si_3N_4$ nano-particles. The structure and micro-structure of coatings was separately analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). Results indicated that nano $Si_3N_4$ and W content in alloy had remarkable effect on micro-structure, micro-hardness and scratch resistant properties. Tungsten content in Ni-W and $Ni-W-Si_3N_4$ alloy ranged from 7 to 14 at.%. Scratch test results suggest that as compared to Ni-W only, $Ni-W-Si_3N_4$ prepared from Ni/W molar ratio of 1:1.5 dispersed with 20 g/L $Si_3N_4$ has shown the best result among different samples.

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Physical Properties of Functional Hanji Added Inorganic Marerials (무기물을 첨가한 기능성 한지의 특성)

  • Jo, Hyun-Jin;Yoon, Seung-Lak;Park, Soung-Bae;Kim, Yun-Geun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.40 no.1
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    • pp.23-28
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    • 2008
  • Functional hanji was manufactured using the bast fiber of Broussonetia kazinoki and various inorganic compounds such as kaolin, talc, elvan, and ocher, and the physical and optical properties were investigated. The residual percentages of kaolin, talc, elvan and ocher in the functional hanji were above 50%. The density of the hanji increased with the increase of the content of inorganic compounds. The hanji manufactured using ocher showed the highest density. The breaking length and burst factor decreased with the increase of inorganic materials, indicating that physical properties of hanji were not improved by adding inorganic materials. The emission rates of far-infrared radiation increased in the hanji manufactured using inorganic materials. The higher emission rates were observed in the hanji with elvan or ocher. Addition of inorganic compounds to hanji showed the flame retardative effect. The colorfastness to light of the hanji with elvan or ocher was the degree of 4, which explained by the characteristic color of the inorganics.

Inhibitory Effect of quercetin-3-O-$\alpha$-L-rhamnopyranoside from Chamaecyparis obtuse on Aldose Reductase and Sorbitol Accumulation (백나무로부터 분리된 quercetin-3-O-$\alpha$-L-rhamnopyranoside의 알도스 환원효소 및 솔비톨 억제효과)

  • Kim, Seon-Ha;Kim, Jin-Kyu;Lee, Yeon-Sil;Bae, Young-Soo;Lim, Soon-Sung
    • Korean Journal of Medicinal Crop Science
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    • v.18 no.5
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    • pp.305-310
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    • 2010
  • Taxifolin-3-O-$\beta$-D-xylopyranoside and quercetin-3-O-$\alpha$-L-rhamnopyranoside were isolated from an EtOAc-soluble extract of the leaves of Chamaecyparis obtuse. Quercetin-3-O-$\alpha$-L-rhamnopyranoside was found to possess a potent inhibitory activity of human recombinant aldose reductase in vitro, its $IC_{50}$ value being $11.5\;{\mu}M$. Kinetic analysis showed that quercetin-3-O-$\alpha$-L-rhamnopyranoside exhibited uncompetitive inhibition against DL-glyceraldehyde. Also, quercetin-3-O-$\alpha$-L-rhamnopyranoside suppresses sorbitol accumulation in rat lens under high glucose conditions, demonstrating the potential to prevent sorbitol accumulation in vivo. These results suggest that this compound may be a promising agent in the prevention or treatment of diabetic complications.

Nutritional Contents of Beverage from Lotus Root and Evaluation of its Physiological Function in Aorta Relation (연근음료의 영양학적 특징 및 흰쥐의 혈관개선에 미치는 효과)

  • Ham, Tae-Sick;Han, Jong-Hyun;Park, Sung-Hye
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.2
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    • pp.490-494
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    • 2005
  • The purpose of this was investigate the possibility of medicinal plants application as an edible functional food resources. We arried out to develop a beverage by using Nelumbo nucifera and we examined the nutritional characterics. Also we examined the effects of drink on physiological function in aorta relation. Thus, the effect of developed beverage on phenylephrine induced contraction of isolated rat thoracic aorta. Contractile force was measured with force displacement thansducer under 1.5g loading tension. Brix, pH and titratable acidity of developed drink were 12.25%, 4.5 and 0.092%. The approximate nutritional composition of beverage was carbohydrate, 9.40%, crude protein, 0.30%, crude fat, 0.25% and ash, 0.15%. Also insoluble fiber and soluble fiber were 1.30%, 0.80%. Developed beverage contained Na(11.45 mg%), K(6.87 mg%), Ca(2.53 mg%). The contraction forces by injection of phenylephrine in isolated thoracic aorta were significantly law in each beverage treatment groups compared with control group. These results that developed drink with medicinal plants can be used as a functional material to decrease aorta contraction.

The Effect of Ions on Thermal Behaviors of Water in Poly(acrylic acid)/Water Mixtures (폴리아크릴산/$H_2O$ 혼합물에서 $H_2O$ 열적 거동에 미치는 이온의 영향)

  • Guan, Lan;Xu, Hongyan;Huang, Dinghai
    • Polymer(Korea)
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    • v.34 no.4
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    • pp.386-389
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    • 2010
  • Thermal behaviors of water in the poly(acrylic acid) (PAA)/water mixtures with 0.1 M NaCl, HCl, and NaOH were investigated by DSC. It showed that adding ions in the mixtures affected the crystallization of water evidently. Compared with the PAA/water mixtures, the $T_m$ of freezable bound water in the mixtures with ions moved to lower values and varied with different cations and anions, due to the stabilization or destabilization of the hydrogen-bonding hydration between polymers and water molecules through ionic hydration. The content of non-freezable bound water in the non-crystalline phase of the PAA/water mixtures with ions was not constant, it increased with total water content gradually, owing to the more binding sites created by ions. The ions could change the distribution of different states of water in the polymer aqueous solutions evidently.

Analysis of Patent Information for the Development of Korea Traditional Herbal Formulation for Acne and that of Functional Cosmetics (여드름 치료 한약 처방과 기능성 화장품의 개발을 위한 특허 자료 분석 연구)

  • Kim, Dong-Il;Kim, Su-Hyun;Ahn, In-Suk;Choi, Min-Sun
    • The Journal of Korean Obstetrics and Gynecology
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    • v.27 no.3
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    • pp.104-115
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    • 2014
  • Objectives: As treating acne is difficult and demands of cosmetic are increasing, the development of new Korea traditional herbal formulation and functional cosmetics of acne is required. The aim of this study is the discovery and composition for the development of new Korea traditional herbal formulation and functional cosmetics of acne. Methods: Searched patent informations related to herbal cosmetics published in 1996~2014, we extracted the patent information and analysis component about effecting of anti-inflammatory and anti-acne. Results: Out of 759 patent informations we searched, 72 those about effecting anti-inflammatory and anti-acne were selected. Also, 159 components of 72 patent informations were reclassified by frequency and characteristic. Conclusions: We expect the effect and safety of new traditional herbal formulation which is composed of high frequency herb in patent informations related to herbal cosmetics.

The Effects of Manual Drainage Lymph (MLD) on the Volume of the Upper Extremities of Women with Breast Cancer (림프마사지(MLD)가 유방암 절제술을 한 여성의 상지 부피에 미치는 영향)

  • Lee, Min-ji;Kwon, O-kook;Yang, Young-sik;Kim, Youn-jin;Lee, Ho-jun
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.25 no.1
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    • pp.53-61
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    • 2019
  • Background: This study aimed to investigate the effects of manual lymph drainage (MLD) on women with breast cancer and lymph edema. Methods: This study was carried out with a total of 23 women with breast cancer and lymph edema. By drawing lots, women were assigned to either the manual drainage group (MLD, n=12), a control group (n=11). Outcomes such as the arm size, visual analogue scale, shoulder pain and disability index, and functional assessment cancer therapy-breast (FACT-B) were measured to 0 week, 2 weeks, 4 weeks, and 8 weeks intervention for both groups. Results: A significant difference was found in the arm size, pain, functional disability level, and quality of life between the two groups and time(p<.01). Significant difference in functional disability level between 2 and 8 weeks at 4 weeks and 8 weeks for pain(p<.01), and the quality for life was significantly different at all time points (p<.01). Conclusions: Applying MLD treatment to women with breast cancer proved to have a positive effect.

The Effects of Digital Signage on Flow and Brand Attitudes: The Mediating Role of Pleasure

  • Ji, Kyoungha;Kim, Hanna
    • Journal of Fashion Business
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    • v.22 no.6
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    • pp.53-69
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    • 2018
  • In recent years, digital media providing entertainment and information have become an important channel of customer experience. The aim of this study is to evaluate the effects of digital signage's characteristics on flow and brand attitudes and to verify the mediating role of pleasure in digital signage and flow. The stimuli were developed for a sports brand stores using 3D and video editing software. The survey was conducted on 544 subjects from both gender aged 20 to 49 years old, i.e. the population that constitutes the major target group for sports brands. The data collected was analyzed using IBM SPSS 24.0. Specifically, frequency analysis, factor analysis, reliability analysis, t-test, and regression analysis were performed on the data. Based on the results, we can draw the following conclusions; First, the dimension of digital signage was classified into aesthetic and functional attributes. Additionally, we found out that women highly value aesthetic attributes of digital signage while the customers in their 40s pay more attention to functional attributes than their counterparts aged 20-30 years. Second, our results suggest that pleasure has a mediating effect in the relationship between digital signage attributes and flow; specifically, both sub-dimensions of digital signage features (aesthetic attributes and functional attributes) affect flow by means of pleasure. Third, our results demonstrated that the flow of digital signage had a significant impact on brand attitudes.