• Title/Summary/Keyword: ) Composition

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A Study on the High Strength of porcelain insulators for transmission line (송전용 자기재 현수애자의 고강도 특성 연구)

  • Cho, H.G.;Han, S.W.;Park, K.H.;Choi, Y.K.;Lee, D.I.;Choi, I.H.;Kim, T.Y.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05e
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    • pp.85-88
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    • 2003
  • In this study, porcelain insulator samples which have a different alumina composition were manufactured in order to test electrical and mechanical properties and make an analysis of the propagation phenomena of micro cracks on porcelain body. From XRD quantitative analysis the crystalline phases were different with alumina composition, sample C and D which have about 17wt% Corundum phase without the Cristobalite phase shows better electrical and mechanical properties than sample A and 8 which have the Cristobalite phase. In dielectrics test on porcelain samples with below 17wt% alumina composition, it was found that the amount of glass phase$(SiO_2)$have an main effect to decrease the dielectric loss$(tan{\delta})$, and the dielectric breakdown voltage of aluminous porcelain insulators was largely affected by its relative density. As a micro cracks analysis, HRS were measured, then the intensity of HRS increased with the amount of alumina composition. On the other hand, the propagation behaviors of cracks was fairly influenced by the distribution of pores.

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Diet composition and feeding strategy of John Dory, Zeus faber, in the coastal waters of Korea

  • Kim, Han Ju;Kim, Hyeong-Gi;Oh, Chul-Woong
    • Journal of Ecology and Environment
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    • v.44 no.1
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    • pp.54-61
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    • 2020
  • Background: Most fish undergo prey switch from juvenile to adult. It is thought that slightly different feeding habits occur among adult fishes due to growth, spawning, habitat change, and so on. Therefore, the diet of the John Dory Zeus faber (≥ 24 cm TL) was studied in the coastal waters of Korea by analysis of stomach contents, with comparison by season and size class of diet composition and prey diversity. Monthly samples were taken from February 2017 to January 2018. Results: The results showed that the John Dory was a piscivorous predator, and pisces had occupied 82.3% of IRI%. Trichiurus lepturus and Trachurus japonicus were important preys in all size classes and seasons. Diet composition differed among the size classes and seasons (Chi-square test, P < 0.05). As body size of Z. faber increased, the occurrence of benthic fish (Glyptocephalus stelleri) tended to increase. The seasonal prey composition also changed depending on the abundant species of each season. Conclusions: Z. faber is a piscivorous predator. The consumption habits of Z. faber appear to different results by their size and seasons. This study suggests that Z. faber could be considered an opportunistic predator.

Effects of Precursor Composition on the $J_c$ of YBCO thin Films Prepared by DCA-MOD Method (DCA-MOD 방법으로 제조하는 YBCO 박막의 임계전류밀도에 미치는 전구체 조성의 효과)

  • Kim, Byeone-Jin;Kim, Hye-Joo;Lee, Jong-Beum;Lee, Hee-Gyoun;Hong, Gye-Won
    • Progress in Superconductivity
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    • v.9 no.1
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    • pp.91-95
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    • 2007
  • [ $YBa_2Cu_3O_{7-{\delta}}$ ] films have been prepared on $LaAlO_3$ (100) single-crystal substrates by the metal organic deposition using dichloroacetate precursors (DCA-MOD). DCA precursor solutions with different composition such as; Yttrium-excess(15 at%), barium-poor(25 at%), and a stoichiometric(Y:Ba:Cu=1:2:3) were prepared in order to investigate the effects of precursor composition on the properties of YBCO films prepared by DCA-MOD method. Coated films were calcined at low temperature up to $500^{\circ}C$ in flowing humid oxygen atmosphere. Conversion heat treatment was performed $800^{\circ}C$ for 2 h in flowing Ar gas containing 1000 ppm oxygen with a humidity of 9.45%. For the film prepared using excess yttrium composition, high critical current density ($J_c$) of $>2MA/cm^2$ was obtained whereas, for the films prepared using barium-poor composition, $J_c$ was lower than $1MA/cm^2$.

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A Study on Spacial Characterristics of MVRDV's Architecture (MVRDV의 건축에 나타난 공간 구성 수법에 관한 연구)

  • Cho, Young-Bae
    • Korean Institute of Interior Design Journal
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    • v.17 no.1
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    • pp.77-83
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    • 2008
  • MVRDV is most important architect as created interesting architectural space in contemporary architecture, and so they applies to the unique theory in their architecture. They used to architectural diagram, program, datascape, density as a design tool. Especially, they have create new architectural space and form in using architectural diagram, program, datascape, density, and void. So, this study is purposed to explain how they use as architectural tool to make composition of it's architectural space and is purpose to explain what is their main concept in architectural space. MVRDV's architectural space has fundamental methodology. That is Datascape on uncertainty and continuity between urban space and architectural space. The former consist in using diagram and architectural program and the latter consist in operating architectural void and inner continuity surface. The conclusion is follows 1. The mode of spacial composition by architectural void is correspond density of city as MVRDV's architectural thinking. 2. The mode of spacial composition by architectural program is ambiguous to the boundary between inner and exterior space by transparency. 3. The mode of spacial composition by architectural diagram make to generate the architectural form and space, through the reinterpretation and relocation of architectural program. 4. The mode of spacial composition inner continuity plane is make relative between site and inner space.

Organic Solvent-Tolerant Esterase from Sphingomonas glacialis Based on Amino Acid Composition Analysis: Cloning and Characterization of EstSP2

  • Dachuri, VinayKumar;Lee, ChangWoo;Jang, Sei-Heon
    • Journal of Microbiology and Biotechnology
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    • v.28 no.9
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    • pp.1502-1510
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    • 2018
  • Organic solvent-tolerant (OST) enzymes are widely applied in various industries for their activity and stability in organic solvents, for their higher substrate solubility, and for their greater stero-selectivity. However, the criteria for identifying OST enzymes largely remain undefined. In this study, we compared the amino acid composition of 19 OST esterases with that of 19 non OST esterases. OST esterases have increased the ratio of Ala and Arg residues and decreased the ratio of Asn, Ile, Tyr, Lys, and Phe residues. Based on our amino acid composition analysis, we cloned a carboxylesterase (EstSP2) from a psychrophilic bacterium, Sphingomonas glacialis PAMC 26605, and characterized its recombinant protein. EstSP2 is a substrate specific to p-nitrophenyl acetate and hydrolyzed aspirin, with optimal activity at $40^{\circ}C$; at $4^{\circ}C$, the activity is approximately 50% of its maximum. As expected, EstSP2 showed tolerance in up to 40% concentration of polar organic solvents, including dimethyl sulfoxide, methanol, and ethanol. The results of this study suggest that selecting OST esterases based on their amino acid composition could be a novel approach to identifying OST esterases produced from bacterial genomes.

Effects of Bedding Materials and Season on the Composition and Production Rate of Broiler Litter as a Nutrient Resource for Ruminants

  • Park, K.K.;Yang, S.Y.;Kim, B.K.;Jung, W.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.11
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    • pp.1598-1603
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    • 2000
  • Broiler litter can be used as a feedstuff for ruminants. Fifty seven litter samples collected from 47 farms in Kyungkee Province of Korea were analyzed to assess the effects of type and amount of bedding (rice hulls vs. sawdust), season (winter vs. summer) and drinkers (bell- vs. trough-type) on composition of broiler litter. Rearing conditions of broilers were also surveyed from the farms to estimate annual production rate of litter. Nutrient composition of broiler litter varied widely and moisture and ash concentrations were higher than observed by other researchers. Ash concentration was higher (p<0.05) for samples taken in winter than in summer and higher (p<0.05) in the rice hulls- than in the sawdust-based litter both in winter and summer. Only minor differences in litter composition were noted between drinkers. Ash was negatively correlated with crude protein and neutral detergent fiber (p<0.01), and acid detergent fiber (p<0.05). The estimated litter production rate was 2.7 kg per bird per flock on a wet basis (60% DM) and the annual production rate was 12.7 kg per bird per yr (60% DM). Therefore, the 42 million broilers per month grown in Korea in 1999 produced a total of 533,400 metric tons of litter.

A Study on Body Composition of the Male Elderly and Female Elderly (남.여 노인의 신체조성에 관한 연구)

  • Um, Ki-Mai;Yang, Yoon-Kwon
    • Journal of Korean Physical Therapy Science
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    • v.7 no.2
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    • pp.475-482
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    • 2000
  • The purpose of this study was to investigate the difference of body composition between male elder and female elder. This study consisted of elder male(n=48) and elder female(n=90). The average age of elder male and female was 73.81, 71.38 years. The data were analyzed with t-test, using SPSS PC+ program. Body composition was measured using Inbody 2.0(seoul, korea) of segmental multi-frequn-cy impedance analyzer technique. The result of this study were the following: 1. The difference of Body composition 1) The muscle mass(kg) of elder male was significantly(P<.00) higher than elder female by 8.30kg. 2) The %fat of elder female was significantly(P<.00) higher than elder male by 8.65%. 3) The WHR(%) elder female was no significantly higher than elder male by 0.01%. 4) The free fat mass(kg) of elder male was significantly(P<.00) higher than elder female by 8.67kg. 5) The TBW(l) of elder male was significantly(P<.00) higher than elder female by 6.081 The factor of significant difference of between elder male and female was muscle mass(kg), %fat, free fat mass(kg), total body water(l).

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A Study on Body Composition of the Elderly according to the Age (연령에 따른 노인의 신체조성에 관한 연구)

  • Um, Ki-Mai
    • Journal of Korean Physical Therapy Science
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    • v.10 no.2
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    • pp.137-144
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    • 2003
  • The purpose of this study was to investigate the difference of body composition of the elderly according to the age. This study consisted of elder male(n=48) and elder female(n=58). The average age of male elder and female elder was 73.81, 73.05 years. The data were analyzed with t-test, using SPSSWIN 10.1 program. Body composition was measured using Inbody 3.0(seoul, korea) of segmental multifrequency impedance analyzer technique. The result of this study were the following : 1. The difference of body composition according to the age 1) The MV(Muscle Volume)of male elder was significant difference among group(p<.05). The MV of female elder was very significant difference among group(p<.01). 2) The %FAT of male elder and female elder was no significant difference among group. 3) The FFM(Free Fat Mass)of male elder was significant difference among group(p<.05). The FFM of female elder was very significant difference among group(p<.01). 4) The TBW(Total Body Water)of male elder was significant difference among group(p<.05) The TBW of female elder was very significant difference among group(p<.01). 5) The WHR(Waist to Hip Ratio)of male elder was significant difference among group(p<.05). The WHR of female elder was very significant difference among group(p<.01).

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Efficiency of Board Composition on Firm Performance: Empirical Evidence from listed Manufacturing Firms of Bangladesh

  • Rahman, Md. Musfiqur;Saima, Farjana Nur
    • The Journal of Asian Finance, Economics and Business
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    • v.5 no.2
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    • pp.53-61
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    • 2018
  • Corporate governance has received massive attention in academic research nowadays due to several recent corporate failures. Inefficiency of corporate governance mechanisms have driven the minds of the researchers and the policy makers to look with more insights into this area. Board composition, as part of corporate governance mechanism, plays a significant role to achieve company's goals or objectives and ensure transparency and accountability. The objective of this study is to find out the efficiency of board composition through board size, independent directors and female directors on firm performance in the listed manufacturing firms of Bangladesh. In this study, a sample of 162 firm years are considered as the sample during the period of 2011 to 2016. This study finds that large board is the significant explanatory variable in improving firm performance. This study also shows that board independence and female directors have no significant association with firm performance which implies that instrument of corporate governance mechanism particularly board composition is very weak. This study recommends that code of corporate governance, specially the role of independent directors and female directors, should be reformed in the light of cultural and institutional context along with the effective enforcement.

Effects of Progressive Resistance Training on Body Composition, Physical Fitness and Quality of Life of Patients on Hemodialysis

  • Song, Woo-Jung;Sohng, Kyeong-Yae
    • Journal of Korean Academy of Nursing
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    • v.42 no.7
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    • pp.947-956
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    • 2012
  • Purpose: To investigate the effect of progressive resistance training (PRT) on body composition, physical fitness, quality of life, lipid and nutritional profile of patients on hemodialysis (HD). Methods: A non equivalent comparison group pretest and posttest design study was used with 40 participants who were randomly assigned to the exercise group (20 participants) and the comparison group (20 participants). The exercise group received PRT for 30 minutes per session, 3 sessions a week, for 12 weeks, while the comparison group received usual care. The PRT consisted of upper and lower body exercises using elastic bands and sandbags. Outcome measures evaluated were: body composition, physical fitness, quality of life, and lipid profile. Results: Skeletal muscle mass, grip, leg muscle strength, and quality of life all improved significantly in the exercise group. Body fat rate, total cholesterol and triglyceride rate decreased significantly in the exercise group. Conclusion: These results suggest that PRT improves body composition, physical fitness, quality of life, and lipid profile of patients on HD. PRT using elastic bands and sandbags can be utilized as part of a regular care plan for these patients.