• Title/Summary/Keyword: FE analysis method

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The Nutritional Status by Stress on Freshmen of University (대학 신입생의 스트레스 민감 여부에 따른 영양상태)

  • Lee, Young-Hee;Rhie, Seung-Gyo;Won, Hyang-Rye
    • The Korean Journal of Community Living Science
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    • v.17 no.4
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    • pp.81-95
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    • 2006
  • This study was made to find out how stress affect on nutrition status of the college freshmen who were experiencing physical growth and development as well as drastic emotional change. 400 male and female freshmen in 4 year colleges were surveyed respectively through the health check-up procedure for college entrance in February, In order to find out the stress in each group frustration, deprivation, lack of self efficacy, type A behavior and anxiety response were surveyed through 10 questions with total 40 points by assigning 4 points for each question. Diet Status was expressed by DDS (Dietary Diversity Score by 5 food groups) and DVS(Dietary Variety Score). 24-hrs recall method was used to find out the quantity of daily nutrient of EAR(estimated adquacy ratio) by KDRIs(Korean Dietary Recommended Intakes). Nutrition level was analyzed by Can-Pro for professionals (Korea Nutrition Association). And for the quality intake, percentage was calculated and MAR(Mean Adequacy Ratio) were produced. Highest point was obtained in the stress of anxiety with the total 40 score of 30.20, and the scores were 29.79, 28.67, and 28.39 for deprivation, type A behavior and frustration respectively. There was no difference of blood components in accordance with stress type. Stress type was divided into less sensitive group and highly sensitive one and the relationship with the blood nutrient status was observed. The difference of blood component and blood pressure in sensitive and highly sensitive groups was observed in deprivation and anxiety. The index of blood pressure(p<0.05), hemoglobin(p<0.01), HDL-cholesterol(p<0.05), and Fe(p<0.05) was high in the deprivation of sensitive group. Blood pressure and hemoglobin was high in type A of sensitive group(p<0.05). And the contents of blood triglyceride was high in the anxiety of sensitive group(p<0.001) The result of nutrition intake analysis according to stress type showed that there was low intake for energy, riboflavin, and niacin. When the degree of deprivation was high there was a lack of riboflavin intake and there was no significant difference of nutrition intake in lack of self efficacy, type A behavior and anxiety response. Thus, it is necessary for colleges to educate the students to maintain mental stability through various programs and activities after catching a kind and extent of the stress college students we meeting with like the confusion of value system, open heterosexual relationship, and the employment difficulties linked with political uncertainty and economic recession.

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Biomechanical Analysis of Different Thoracolumbar Orthosis Designs using Finite Element Method (유한요소 해석을 이용한 정형용 흉·요추 보조기의 형태에 따른 생체역학적 분석)

  • Kim, Y.H.;Jun, S.C.;Jung, D.Y.;Lee, S.J.
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.6 no.1
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    • pp.45-50
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    • 2012
  • Thoracolumbar orthosis has been used for the rehabilitation of the patients with senile kyphosis. Recently, a number of different thoracolumbar orthosis designs have been introduced but its biomechanical effectiveness still remain unknown. In this study, we compared the pressure distribution on the surface of the trunk and stresses on the orthosis in relation to changes in connecting frame designs (Type 1, one-connecting frame type; Type 2, two-connecting frame type; Type 3, all-in-one type) using finite element (FE) models under different motions of the trunk. The results showed that Type 3 distributed the pressure on the trunk most evenly followed by Type 2 and Type 1 and the difference between Type 1 and Type 2 was negligible. ROM was limited most effectively by Type 3 ($8.5{\sim}9.4^{\circ}$), followed by Type 2 ($11.3{\sim}13.9^{\circ}$) and Type 1 ($12.1{\sim}15.4^{\circ}$). The ratio between the peak von Mises stress and yield strength of each material remained less than 20% regardless of orthosis type indicating low likelihood of component failure. In conclusion, our study found that all-in-one type of orthosis was the most effective design for the conservative treatment of spinal deformity in terms of function and comfort.

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Development of Packaging Materials for MA Packaging(1) (MA포장용 기능성 포장 소재개발에 관한 연구(1))

  • Park, Hyung-Woo;Park, Moo-Hyun;Kim, Hoon;Lee, Jae-Young;Yang, Han-Chul
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.3 no.2
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    • pp.25-31
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    • 1996
  • Various treaments such heating, acid tenting, acid healing, alkaline treating, acid+alkaline renting were attempted to investigate their effects on molar ratio, chemical composition, DTA and specific surface area(SSA) of natural zeolite poder. Molar ratio, Si to AI. of natural zeolite was 4.78, which represented high silica type. Composition of natural zeolite showed that $SiO_2$ was 66.34% $Al_2O_3$ was 13.89%, $Fe_2O_2$ was 1.55% X-ray diffraction showed that main component of natural zeolite was mordenite and clinoptliolite. Differential Thermal Analysis and Thermogravimetry curve of natural zeolite was showed to peak of endothermic peak at $80^{\circ}C$ and it means to the peak of dehydrate reaction, but recristalization was not formed below at $1,000^{\circ}C$. Weight loss during calcination was 16% at $1,000^{\circ}C$. Thermal treatments on SSA of natural zolite powder decreased from $75.2m^2/g\;to\;2.1m^2/g$. In contrast chemical treatments on SSA showed to increase to $300.2m^2/g$(1 N HCl treating), $54.9m^2/g$(1 N NaOH) and $90.9m^2/g$(HCl+NaOH)tudy, it could be proposed to employ acid tret method as packaging materisls for MA packaging.

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Development and Effects' Analysis of Nutrition Education Pamphlet for the Higherr Grades Elementary Students -Focused on Individual Daily Needed Food Exchange Units- (초등학교 고학년용 영양교육 소책자 개발 및 효과 분석 - 하루 필요 식품군 단위수 교육을 중심으로 -)

  • Lim, Eun-Su;Cho, Young-Sook;Kim, Se-Na;Kim, Sook-Bae
    • Korean Journal of Community Nutrition
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    • v.17 no.6
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    • pp.689-706
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    • 2012
  • The purpose of this study was to evaluate effects of a nutrition education focused on Food Exchange System for the higher grades elementary children. Nutrition education lessons (40 min/lesson, 4 times), '5 major nutrients and functions', '6 food groups', 'daily needed energy and food exchange units', 'good choice of snacks and balanced exercise' were provided to elementary students (5th grade students). This research was based on the data from two groups of elementary school children in the 'education' group (n = 31) and 'non-education' group (n = 31). We assessed the changes in dietary attitude, food habit and nutrition knowledge using questionnaire and nutrient intake using 24hr recall method by nutrition education using the developed pamphlet. After education, there was a significant difference in the dietary attitude score only in attitude of 'balanced meal' (p < 0.001) in the education group compared to the non-education group. In food habit, there were significant positive changes in the type of breakfast and in the priority of choosing snack in the educated group. In nutrition knowledge, there were significant increases in scores of 'function of carbohydrate' (p < 0.05), 'function of fat' (p < 0.01), 'function of vitamin' (p < 0.01), 'foods of carbohydrate' (p < 0.01), and 'foods of vitamin' (p < 0.01) in the educated group. After education, carbohydrate: protein: fat (CPF) ratio was significantly different between the two groups (education group, 59 : 16 : 26 vs. non-education group, 63 : 15 : 23). In evaluation of nutrient intake by Dietary Reference Intakes for Koreans (KDRIs), there were significant positive effects in energy (p < 0.05), thiamin (p < 0.05), riboflavin (p < 0.05), vitamin C (p < 0.05), phosphorus (p < 0.01), Fe (p < 0.01) and zinc (p < 0.01) in the education group compared to the non-education group. In conclusion, the developed 4 times' nutritional education pamphlet focused on individual daily energy requirements and food exchange units using food exchange system for higher grades' elementary student may positively change nutrition knowledge and dietary intakes.

Effects of Fusion Level for Scioliotic Spine Correction Simulation with Pedicle Screw and Rod Derotation Method (척추경 나사못 고정과 강봉 감염술을 이용한 척추 측만증 교정 해석시 유합 범위에 따른 교정 효과 분석)

  • 김영은;손창규;최형연;하정현;이춘기
    • Journal of Biomedical Engineering Research
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    • v.25 no.1
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    • pp.71-76
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    • 2004
  • In order to investigate the Post-operative changes in scoliotic spine according to selection of fusion level a mathematical finite element model of King-Moe type II scoliotics spine system was developed. By utilizing this finite element scoliosis model surgical correction simulation procedures of pedicle fixation and derotation were simulated. In consequence of the calculation by changing the fusion Levels, postoperative changes like Cobb angle, apical vertebrae axial rotation (AVAR), thoracic kyphosis, and rib hump were Qualitatively analyzed. In the analysis of operative kinematics, the decrease or Cobb angle was most prominent in distraction than in deroation. Applying the rod derotation only was not effective in decrease of Cobb angle but just caused increase of At AR and rib hump. From the operative simulation, co-action or distraction and translation during rod insertion has major impact on Cobb angle decrease and maintenance of kyphosis. With rod rotation, Cobb angle decrease was obtained, but combined increase of AVAR and rib hump was simulation observed as well. The case of most extended instrumentation range with 60o rod rotation produced double decrease of Cobb angle, but the increase of rib hump and AYAR occurred corresponding1y. The optimum selection of fusion level was proved as one level less than inflection position of the thoracic spine curvature.

Hot Corrosion Behavior of Plasma Sprayed 4 mol% Y2O3-ZrO2 Thermal Barrier Coatings with Volcanic Ash (플라즈마 용사법으로 제작된 4mol% Y2O3-ZrO2 열차폐코팅의 화산재에 의한 고온열화거동)

  • Lee, Won-Jun;Jang, Byung-Koog;Lim, Dae-Soon;Oh, Yoon-Suk;Kim, Seong-Won;Kim, Hyung-Tae;Araki, Hiroshi;Murakami, Hideyuki;Kuroda, Seiji
    • Journal of the Korean Ceramic Society
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    • v.50 no.6
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    • pp.353-358
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    • 2013
  • The hot corrosion behavior of plasma sprayed 4 mol% $Y_2O_3-ZrO_2$ (YSZ) thermal barrier coatings (TBCs) with volcanic ash is investigated. Volcanic ash that deposited on the TBCs in gas-turbine engines can attack the surface of TBCs itself as a form of corrosive melt. YSZ coating specimens with a thickness of 430-440 ${\mu}m$ are prepared using a plasma spray method. These specimens are subjected to hot corrosion environment at $1200^{\circ}C$ with five different duration time, from 10 mins to 100 h in the presence of corrosive melt from volcanic ash. The microstructure, composition, and phase analysis are performed using Field emission scanning electron microscopy, including Energy dispersive spectroscopy and X-ray diffraction. After the heat treatment, hematite ($Fe_2O_3-TiO_2$) and monoclinic YSZ phases are found in TBCs. Furthermore the interface area between the molten volcanic ash layers and YSZ coatings becomes porous with increases in the heat treatment time as the YSZ coatings dissolved into molten volcanic ash. The maximum thickness of this a porous reaction zone is 25 ${\mu}m$ after 100 h of heat treatment.

Preparation and characterization of Poly(2-methacryloyloxyethyl phosphorylcholine/fluorescein O-methacrylate)-coated iron oxide nanoparticles (Poly(2-methacryloyloxyethyl phosphorylcholine/fluorescein O-methacrylate)가 도입된 산화철 나노 입자의 제조 및 발열 특성 연구)

  • Ryu, Sunggon;Cheong, In Woo
    • Journal of Adhesion and Interface
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    • v.19 no.3
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    • pp.106-112
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    • 2018
  • Recently, the hyperthermia treatment of malignant tissues has gained great attention as a biocompatible and benign method that facilitates successful cancer therapy compared to radiation and chemotherapy. In this study, superparamagnetic ($Fe_3O_4$) iron oxide nanoparticles (IONP) coated with biocompatible polymer (IONP@P(MPC/FOM)) for the purpose of hyperthermia treatment were prepared and related characterization were performed. IONPs with having 15 nm diameter were first prepared by coprecipitation and followed by surface modification with 4-cyanopentanoic acid dithiobenzoate (CTP) for reversible addition-fragmentation chain transfer (RAFT) copolymerization by using 2-methacryloyloxyethyl phosphorylcholine (MPC) and fluorescein O-methacrylate (FOM) to form corona layer of P(MPC/FOM) on the surface of the IONP. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) confirmed the morphology and hydrodynamic size of the IONP@P(MPC/FOM) and thermogravimetric analysis (TGA) confirmed the formation of P(MPC/FOM) corona layer, respectively. Exposing IONP dispersion to alternating magnetic field suggests that the IONP@P(MPC/FOM) aqueous dispersion with 0.2 wt.% can be used for hyperthermia treatment.

Fabrication of Photocatalyst Glass Beads Coated with TiO2 Thin Film by a Layer-by-Layer Process (LBL법에 의해 TiO2막이 코팅된 광촉매 글라스 비드 제조)

  • Lee, Ji-Sun;Chae, Yoo-Jin;Lee, Mi-Jai;Kim, Sei-Ki;Hwang, Jong-Hee;Lim, Tae-Young;Hyun, Soong-Keun;Kim, Jin-Ho
    • Korean Journal of Materials Research
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    • v.22 no.7
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    • pp.379-383
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    • 2012
  • $TiO_2$ thin films consisting of positively charged poly(diallyldimethylammonium chloride)(PDDA) and negatively charged titanium(IV) bis(ammonium lactato) dihydroxide(TALH) were successfully fabricated on glass beads by a layer-by-layer(LBL) self-assembly method. The glass beads used here showed a positive charge in an acid range and negative charge in an alkaline range. The glass beads coated with the coating sequence of(PDDA/TALH)n showed a change in the surface morphology as a function of the number of bilayers. When the number of bilayers(n) of the(PDDA/TALH) thin film was 20, Ti element was observed on the surface of the coated glass beads. The thin films coated onto the glass beads had a main peak of the (101) crystal face and were highly crystallized with XRD diffraction peaks of anatase-type $TiO_2$ according to an XRD analysis. In addition, the $TiO_2$ thin films showed photocatalytic properties such that they could decompose a methyl orange solution under illumination with UV light. As the number of bilayers of the(PDDA/TALH) thin film increased, the photocatalytic property of the $TiO_2$-coated glass beads increased with the increase in the thin film thickness. The surface morphologies and optical properties of glass beads coated with $TiO_2$ thin films with different coating numbers were measured by field emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD) and by UV-Vis spectrophotometry(UV-vis).

Microstructure evolution and effect on deuterium retention in oxide dispersion strengthened tungsten during He+ irradiation

  • Ding, Xiao-Yu;Xu, Qiu;Zhu, Xiao-yong;Luo, Lai-Ma;Huang, Jian-Jun;Yu, Bin;Gao, Xiang;Li, Jian-Gang;Wu, Yu-Cheng
    • Nuclear Engineering and Technology
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    • v.52 no.12
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    • pp.2860-2866
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    • 2020
  • Oxide dispersion-strengthened materials W-1wt%Pr2O3 and W-1wt%La2O3 were synthesized by wet chemical method and spark plasma sintering. The field emission scanning electron microscopy (FE-SEM) analysis, XRD and Vickers microhardness measurements were conducted to characterize the samples. The irradiations were carried out with a 5 keV helium ion beam to fluences up to 5.0 × 1021 ions/m2 under 600 ℃ using the low-energy ion irradiation system. Transmission electron microscopy (TEM) study was performed to investigate the microstructural evolution in W-1wt%Pr2O3 and W-1wt%La2O3. At 1.0 × 1020 He+/m2, the average loops size of the W-1wt%Pr2O3 was 4.3 nm, much lower than W-1wt% La2O3 of 8.5 nm. However, helium bubbles were not observed throughout in both doped W materials. The effects of pre-irradiation with 1.0 × 1021 He+/m2 on trapping of injected deuterium in doped W was studied by thermal desorption spectrometry (TDS) technique using quadrupole mass spectrometer. Compared with the samples without He+ pre-irradiation, deuterium (D) retention of doped W materials increased after He+ irradiation, whose retention was unsaturated at the damage level of 1.0 × 1022D2+/m2. The present results implied that irradiation effect of He+ ions must be taken into account to evaluate the deuterium retention in fusion material applications.

Relationship between Polyphenol Oxidase Activity and Color of White Salted Noodles Prepared from Korean Wheat Cultivar (국산밀의 폴리페놀 산화 효소 활성과 국수 색과의 관계)

  • Kang, Chon-Sik;Kim, Kyeong-Hoon;Park, Jong-Chul;Kim, Kyung-Ho;Park, Kwang-Geun;Cheong, Young-Keun;Yoon, Sung-Joong;Park, Chul Soo
    • Korean Journal of Breeding Science
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    • v.43 no.5
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    • pp.470-478
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    • 2011
  • This study was carried out to find major factors affecting the color of wheat flour and noodles and develop simple analysis method for the breeding of wheat cultivars suitable for producing flour and noodles with bright color which are preferred by consumers. Customers who buy white noodle or flour prefer bright-colored food to dark-colored products. We evaluated grains of 25 Korean wheat cultivars for chemical composition, grain characteristics, and color change of noodle dough sheets during storage. Polyphenol oxidase (PPO) has been connected to discoloration of white salted noodles and other wheat end products. The grain PPO activity was reduced as the 1,000 grain weight, grain ash content, and protein content decreased. The grain PPO activity was positively correlated with the total polyphenol content ($r=0.609^{**}$) and iron content ($r=0.655^{**}$). Lightness, protein, polyphenol and Fe content of flour were positively correlated with PPO activity of grain. Cultivars with higher grain PPO activity showed darker noodles and were more easily discolored during the storage (from 2 hr to 48 hr). Thus, PPO activity can be used as a selection index in a breeding program for wheat cultivars of bright-colored flour.