• Title/Summary/Keyword: GR/A

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The Study of Mixed Convection in a Room with Heated Bottom Surface and various Partitions (밑면이 가열되고 다양한 격판을 가진 실내공간에서의 혼합대류 열전달)

  • Lee, C.J.
    • Solar Energy
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    • v.18 no.1
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    • pp.91-98
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    • 1998
  • The study of mixed convection in a room with heated bottom surface and various partitions has been numerically investigated using a finite volume method. The parameters studied here are, 50$\overline{Nu}=\overline{Nu_n}{\cdot}(1+c(Re/Gr^{1/2})^d)$, where $\overline{Nu_n}$ corresponds to pure natural convextion.

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A Study of Characteristics on the Dissimilar Metals (Alloy Steel : A387 Gr. 91 - Carbon Steel : A516 Gr. 70) Welds Made with FCA Multiple Layer Welding : Part 1 (합금강(ASTM A387 Gr. 91) - 탄소강(ASTM A516 Gr.70) 이종금속의 FCA 다층 용접부 특성 평가 : Part. 1)

  • Shin, Tae Woo;Jang, Bok Su;Koh, Jin Hyun
    • Journal of Welding and Joining
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    • v.34 no.3
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    • pp.61-68
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    • 2016
  • Characteristics of dissimilar metal welds between alloy steel ASTM A387 Gr. 91 and carbon steel ASTM A516 Gr.70 made with Flux cored arc welding(FCAW) have been evaluated in terms of microstructure, mechanical strength, chemical analysis by EDS as well as corrosion test. Three heat inputs of 15.0, 22.5, 30.0kJ/cm were employed to make joints of dissimilar metals with E91T1-B9C wire. Post-weld heat treatment was carried out at $750^{\circ}C$ for 2.5 h. Based on microstructural examination, tempered martensite and lower bainite were formed in first layer of weld metal. The amount of tempered martensite was decreased and the amount of lower bainite was increased with increasing heat input and layer. Heat affected zone of alloy steel showed the highest hardness due to the formation of tempered Martensite and lower Bainite. Tensile strengths of dissimilar welds decreased with increasing heat inputs. Dissimilar welds seemed to have a good hot cracking resistance due to the low HCS index below 4. The salt spray test of dissimilar metals showed that the corrosion rate increased with increasing heat inputs due to the increase of the amount of lower Bainite.

Modified Drum Priming and Exogenous Application of 24-Epibrassinolide (24-EBL) for Enhancing Germination under High Temperature Condition in Lettuce Seeds

  • Kang, Won Sik;Kim, Min Geun;Kim, Du Hyun
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.86-86
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    • 2018
  • This study was conducted to investigate the effects of modified drum priming and 24-Epibrassinolide (24-EBL) treatment to improve the seed quality for export. 40, 50 and 60% seed moisture content (SMC) of hydrated seeds were incubated for 16 and 24 h in a container with a relative humidity of 99% at 26 rpm for a modified drum priming treatment. The treated seeds were sown at $20^{\circ}C$ and $30^{\circ}C$ (12/12h, light/dark) with four replications of 25 seeds on pleated paper. The seeds were hydrated with water or 24-EBL solutions of $10^{-7}$, $10^{-8}$ and $10^{-9}M$, respectively. The germination of the modified drum primed seeds (24 h incubation after 60% SMC hydration) improved to 1.6 days mean germination time (MGT) and $46%{\cdot}day^{-1}$ germination rate (GR), while the untreated seeds showed 2.1 days MGT and $28%{\cdot}day^{-1}$ GR. The modified drum priming (60% SMC and 24 h incubation with $10^{-9}M$ 24-EBL) showed improved results in MGT (1.8 days) and GR (55%) at $20^{\circ}C$, whereas untreated seeds showed 2.3 days MGT and 44% GR. Under $30^{\circ}C$, germination of modified drum primed seeds was significantly improved in GP (80%), GR ($31%{\cdot}day^{-1}$), HS (55%) and MGT (3.3 days), however, untreated seeds showed decreased GP (27%), GR ($22%{\cdot}day^{-1}$), HS (55%) and MGT (4.8 days). This study showed that the germination of lettuce seeds is enhanced by 24 h drum incubation with 24-EBL and this method can be used effectively to achieve the benefits of early germination and uniform seedling development. In addition, these treatments circumvent thermo-dormancy of lettuce seed and have a possibility of high-quality and environment-friendly seed processing.

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Rheinheimera aquatica sp. nov., Antimicrobial Activity-Producing Bacterium Isolated from Freshwater Culture Pond

  • Chen, Wen-Ming;Lin, Chang-Yi;Young, Chiu-Chung;Sheu, Shih-Yi
    • Journal of Microbiology and Biotechnology
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    • v.20 no.10
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    • pp.1386-1392
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    • 2010
  • A bacterial strain designated GR5$^T$, previously isolated from a freshwater culture pond in Taiwan while screening for bacteria for antimicrobial compounds, was characterized using a polyphasic taxonomic approach. Strain GR5$^T$ was found to be Gram-negative, aerobic, greenish-yellow colored, rod-shaped, and motile by means of a single polar flagellum. Growth occurred at $10-40^{\circ}C$ (optimum, $35^{\circ}C$), pH 7.0-8.0 (optimum pH 8.0), and with 0-2.0% NaCl (optimum, 0.5-1.0%). The major fatty acids were $C_{16:1}{\omega}7c$(36.3%), $C_{16:0}$(16.6%), $C_{12:0}$ 3-OH (12.5%), and $C_{18:1}{\omega}7c$(9.1%). The major respiratory quinone was Q-8, and the DNA G+C content of the genomic DNA was 51.9 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain GR5$^T$ belongs to the genus Rheinheimera, where its most closely related neighbors are Rheinheimera texasensis A62-14B$^T$ and Rheinheimera tangshanensis JA3-B52$^T$ with sequence similarities of 98.1% and 97.5%, respectively, and the sequence similarities to any other recognized species within Gammaproteobacteria are less than 96.5%. The mean level of DNA-DNA relatedness between strain GR5$^T$ and R. texasensis A62-14B$^T$, the strain most closely related to the isolate, was $26.5{\pm}7.6%$. Therefore, based on the phylogenetic and phenotypic data, strain GR5$^T$ should be classified as a novel species, for which the name Rheinheimera aquatica sp. nov. is proposed. The type strain is GR5$^T$ (=BCRC 80081$^T$=LMG 25379$^T$).

Synthesis of Multiwall Carbon Nanotube/Graphene Composite by Aerosol Process and Its Characterization for Supercapacitors (에어로졸 공정에 의한 Multiwall carbon nanotube/Graphene 복합체 제조 및 슈퍼커패시터 특성평가)

  • Jo, Eun Hee;Kim, Sun Kyung;Chang, Hankwon;Lee, Chong Min;Park, Su-Ryeon;Choi, Ji-hyuk;Jang, Hee Dong
    • Particle and aerosol research
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    • v.12 no.4
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    • pp.127-134
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    • 2016
  • A multiwall carbon nanotube (MWCNT)/graphene (GR) composite was synthesized for an enhanced supercapacitor. Aerosol spray pyrolysis (ASP) was employed to synthesize the MWCNT/GR composites using a colloidal mixture of MWCNT and graphene oxide (GO). The effect of the weight ratio of the MWCNT/GO on the particle properties including the morphology and layered structure were investigated. The morphology of MWCNT/GR composites was generally the shape of a crumpled paper ball, and the average composite size was about $5{\mu}m$. MWCNT were uniformly dispersed in GR sheets and the MWCNT not only increase the basal spacing but also bridge the defects for electron transfer between GR sheets. Thus, it was increasing electrolyte/electrode contact area and facilitating transportation of electrolyte ion and electron in the electrode. Electrochemical data demonstrate that the MWCNT/GR (weight ratio=0.1) composite possesses a specific capacitance of 192 F/g at 0.1 A/g and good rate capability (88% capacity retention at 4 A/g) using two-electrode testing system.

Retrospective study on 100 cases of inpatients with facial paralysis (구안와사(말초성 안면신경마비) 입원환자 100례에 대한 임상적 고찰)

  • Kim, Min-Jeong;Kim, Jong-Han;Park, Soo-Yeon;Choi, Jeong-Hwa;Jung, Min-Young;Song, Jin-Su;Lee, Eu-Jin;Lee, Ji-Eun;Yang, Mi-Sung
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.22 no.2
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    • pp.128-138
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    • 2009
  • Objectives : The purpose of this study is to make a survey on the oriental medical care and to enlarge the domain of oriental medical treatment concerning facial paralysis. Methods : From May 2008 to April 2009, a clinical study was done on 100 inpatients who were diagnosed and treated as facial nerve paralysis at Mok-dong Oriental Medicine Hospital, Dong-shin University Results : The result were as the following 1. The distribution of sex: male 35%, female 65%. The distribution of age was disclosed that fifty was the most in 22 cases(22%). 2. The distribution of the region of facial palsy: Lt 58%(male 23%, female 35%) Rt 41%(male 11%, female 30%) 3. In distribution of contributing frequence in month, June was the most in number(12%) and in season, spring, summer, winter were the same percentage(26%). 4. In distribution of cause, stress(34%), excessive labor(25%), unknown(22%) were investigated higher than other conditions. 5. The distribution of past history: hypertension 14%, diabetes mellitus 4%, both(hypertension, diabetes mellitus) 6% 6. The distribution of period before admission: within a week 80%, 1$\sim$2 week 8%, 3$\sim$4 week 6% in order. 7. The distribution of attended symptoms: mastoid pain 43 cases, dryness of eye 26 cases, tearing 22 cases, headache 12 cases, dizziness 9 cases in order. 8. Other offices patients visited before coming to this clinic: oriental clinic or hospital 35%, local clinic or hospital 29%, none 26%, both(oriental clinic & local clinic) 10%. 9. The distribution of House-Brackmann grade on admission: Gr III 38%, Gr IV 26%, Gr II 22%, Gr V 14% in order. 10. The distribution of House-Brackmann grade on discharge: Gr II 34%, Gr I 32%, Gr III 22%, Gr V 7%, Gr IV 5% in order.

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Investigation of Korean Maize Lines: N. Inbreeding Depression, Heterosis and Homozygosity of 69 Korean Maize Lines (재래종 옥수수 수집종에 대한 특성조사(IV))

  • ;Bong-Ho Chae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.25 no.3
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    • pp.21-30
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    • 1980
  • This is the fourth report in serial studies on the botanical characters of Korean maize lines collected. Several plant characters and genetical nature of lines were investigated and compared among selfed, sibbed and test crossed lines. Inbreeding depression and heterosis, and homozygosity expressed in percent were calculated. Throughout the study a great extent of variation of plant characters and genetical variation expressed in terms of inbreeding depression and heterosis were observed. The observed plant and genetic variation of plant characters were assumed to be enough for providing new breeding materials for future maize breeding program. The degree of homozygosity of Korean local maize lines suggested that a great portion of maize grown by Korean farmers presently are near or close to inbred and presumed to show a great heterosis when crossed to divergent lines.

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Construct Validity of Korean Translated Gifted Rating Scale (한국어판 Gifted Rating Scale의 구인타당도)

  • Lee, Dong-Hyuck
    • Journal of Gifted/Talented Education
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    • v.20 no.2
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    • pp.595-619
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    • 2010
  • This study examined the construct validity of a Korean translated version of the Gifted Rating Scales-School Form (GRS-S). Data were collected from five elementary schools in a metropolitan area and a midsize town in South Korea. Confirmatory factor analysis results indicated that the original factor structure (6-factor solution) fit the data collected from the teachers. However, the 6-factor solution did not fit the data collected from the parents. Thus, exploratory factor analysis was conducted for the parent data. The results showed that seven factors were extracted, and the factors explained 71.96% of the total variance. Unlike the original factor structure, some items of the academic ability scale were grouped with intellectual ability scale, and a creativity scale item and another academic ability scale item were an independent factor. The study outcomes provide preliminary support for a translated version of the GRS-S with elementary students in Korea. More detailed interpretations and implications of the results are discussed in the study.

Convective Heat Transfer in Ventilated Space wit=h Various Partitions

  • Bae, Kangyoul;Chung, Hanshik;Jeong, Hyomin
    • Journal of Mechanical Science and Technology
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    • v.16 no.5
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    • pp.676-682
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    • 2002
  • The laminar convective heat transfer in ventilated space with various horizontal partitions was studied numerically and experimentally For the numerical study, the governing equations were solved by using a finite volume method for various numbers Re, Gr, Pr and partition numbers. The experimental study was conducted by using a holographic interferometer. The isotherms and velocity vectors have been presented for various parameters. As the number and length of partition increased, convective heat transfer decreased. Based on the numerical data, correlation equations were obtained for the mean Nusselt number in term of Gr/Re$^2$. In the region of Gr/Re$^2$$\leq$ 1, the mean Nusselt number was small, but in the region of Gr/Re$^2$> 1, the mean Nusselt number was constant.

PROBIOTICS AND HEALTH

  • Reid, Gregor
    • Proceedings of the Korean Society of Food Science and Nutrition Conference
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    • 2001.12a
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    • pp.152-160
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    • 2001
  • The ability of microbial strains to confer health benefits to human and animal hosts is not a feature of many organisms. Lactic acid bacteria are the most commonly used bacteria applied as probiotics and there is now strong evidence that certain strains confer tangible benefits to the host. In terms of preventing infection, the ability of probiotic lactobacilli to colonize the tissue site, even temporarily, and inhibit growth and adhesion of pathogens, has been documented. Using molecular tools, such as RAPD and DGGE, probiotic organisms can be tracked through the intestine and in the vagina, and their impact on the flora assessed. Arguably, strains L. rhamnosus GG and GR-l are the most studied probiotic strains in terms of human application to the gut (GG and GR-l) and vagina (GR-1). Combined with L. fermentum RC-14, GR-l provides a two-pronged therapeutic for the intestine and urogenital tract. Care in manufacturing and distribution is essential to ensure that optimal doses of probiotics are accessible to consumers and patients.

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