• 제목/요약/키워드: CRAM

검색결과 64건 처리시간 0.025초

일방향응고 Ni기초내열합금 GTD-111의 천이액상확산접합(I) (Transient Liquid Phase Bonding of Directionally Solidified Ni Base Superalloy, GTD-111(I) - Bonding Phenomena and Mechanism -)

  • 강정윤;권민석;김인배;김대업;우인수
    • Journal of Welding and Joining
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    • 제21권2호
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    • pp.82-88
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    • 2003
  • The bonding phenomenon and mechanism in the transient liquid phase bonding(TLP Bonding) of directionally solidified Ni base superalloy, GTD-111 was investigated. At the bonding temperature of 1403K, liquid insert metal was eliminated by isothermal solidification which was controlled by the diffusion of B and Si into the base metal and solids in the bonded interlayer grew epitaxially from mating base metal inward the insert metal. The number of grain boundaries formed at the bonded interlayer was corresponded with those of base metal. The liquation of grain boundary and dendrite boundary occurred at 1433K. At the bonding temperature of 1453K which is higher than liquation temperature of grain boundary, liquids of the Insert metal were connected with liquated grain boundaries and compositions in each region mixed mutually. In Joints held for various time at 1453t phases formed at liquated grain boundary far from the interface were similar to those of bonded interlayer. With prolonged holding time, liquid phases decreased gradually and liquids of continuous band shape divided many island shape. But liquid phases did not disappeared after holding for 7.2ks at 1453k. Isothermal solidification process at the bonding temperature which is higher than the liquation temperature of the grain boundary was controlled by diffusion of Ti to be result in liquation than B or Si. in insert metal. (Received January 15, 2003)

잠제상에 설치된 표식암(의암)에 작용하는 규칙파파력의 실험적 연구 (Wave force Acting on the Artificial Rock installed on a Submerged Breakwater in a Regular Wave field)

  • 배기성;허동수
    • 한국해양공학회지
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    • 제16권6호
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    • pp.7-17
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    • 2002
  • Recently, artificial rocks, instead of buoys, have been placed on the submerged breakwater to indicate its location. The accurate estimation of wave forces on these rocks is deemed necessary for their stability design. Characteristics of the wave force, however, are expected . to be very complicated because of the occurrence of breaking or post-breaking waves. In this regard, wave forces exerted on an artificial rock have been investigated in this paper. The maximum wave force has been found to strongly dependent on the location and shape of the artificial rock that is placed on the submerged breakwater. The plunging breaker occurs near the loading cram edge of a submerged breakwater, which cause impulsive breaking wave force on the rock. Using the Morison equation, with the velocity and acceleration at the front face of the artificial rock and varying water surface level, it is possible to estimate wave forces, even impulsive breaking wave forces, that are acting on the rock installed on a submerged breakwater. The vertical wave force is also found to depend, significantly, on the buoyant force.

Antimicrobial Effects of Ocotillone Isolated from Stem Bark of Ailanthus altisshima

  • Lee, Dong-Gun;Chang, Young-Su;Park, Yoon-Kyung;Hahm, Kyung-Soo;Woo, Eun-Rhan
    • Journal of Microbiology and Biotechnology
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    • 제12권5호
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    • pp.854-857
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    • 2002
  • Bioassay-directed chromatographic fractionation of a methylene chloride extract of Ailanthus altisshima indicated the presence of 20(S), 24(R), epoxy-25-hydroxydammarane-3-one (compound 1, ocotillone) which was isolated from this plant, for the first time. Antimicrobial activity of compound 1 was measured by inhibition of bacterial and fungal cells growth and by a hemolytic assay with human erythrocytes, respectively. The results revealed that compound 1 had potent antibacterial activity against Cram-negative bacteria, P. aeruginosa and S. typhimurium, that were without hemolytic activity, whereas it had weak antimicrobial activity against Gram-positive bacteria and fungi. These results demonstrated that the compound 1 has more antibacterial activity against 6ram-negative bacteria, which have no hemolytic activity, than Gram-positive bacteria and fungi. This is the first report on the biological activities of the compound 1.

Effect of Enterococcus faecalis strain PL9003 on Adherence and Growth of Helicobacter pylori

  • Nam, Hye-Ran;Ha, Mi-Sun;Lee, En-Jung;Lee, Yeon-Hee
    • Journal of Microbiology and Biotechnology
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    • 제12권5호
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    • pp.746-752
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    • 2002
  • The purpose of the present study was to examine the antagonistic activities of Enterococcus faecalis strain PL9003 (PL9003) on Helicobacter pylori. This strain was isolated from infant feces and found to inhibit both the growth of H. pylori and its in vitro adherence to the human gastric cell line MKN-45. The binding of PL9003 to MKN-45 was observed under a light microscope after Cram staining and under a scanning electron microscope. When detected with an FITC-conjugate antibody, both viable and nonviable PL9003 were found to decrease the number of H. pylori bound to MKN-45. When detected by an enzyme-linked immunoabsorbent assay, about 70% of the H. pylori bound on MKN-45 disappeared with the four-1314 addition of viable or nonviable PL9003. The spent culture supernatant (SCS) of PL9003 also decreased the viability of H pylori even after neutralization and pepsin treatment. The above results suggest that PL9003 has a potential as a new probiotic for the stomach.

고의서에 나타난 경혈과 병증의 연관성 측정 및 시각화 - 침구자생경 분석 예를 중심으로 - (Measure of the Associations of Accupoints and Pathologies Documented in the Classical Acupuncture Literature)

  • 오준호
    • Korean Journal of Acupuncture
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    • 제33권1호
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    • pp.18-32
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    • 2016
  • Objectives : This study aims to analyze the co-occurrence of pathological symptoms and corresponding acupoints as documented by the comprehensive acupuncture and moxibustion records in the classical texts of Far East traditional medicine as an aid to a more efficient understanding of the tacit treatment principles of ancient physicians. Methods : The Classic of Nourishing Life with Acupuncture and Moxibustion(Zhenjiu Zisheng Jing; hereinafter ZZJ) was selected as the primary reference book for the analysis. The pathology-acupoint co-occurrence analysis was performed by applying 4 values of vector space measures(weighted Euclidean distance, Euclidean distance, $Cram\acute{e}r^{\prime}s$ V and Canberra distance), which measure the distance between the observed and expected co-occurrence counts, and 3 values of probabilistic measures(association strength, Fisher's exact test and Jaccard similarity), which measure the probability of observed co-occurrences. Results : The treatment records contained in ZZJ were preprocessed, which yielded 4162 pathology-acupoint sets. Co-occurrence was performed applying 7 different analysis variables, followed by a prediction simulation. The prediction simulation results revealed the Weighted Euclidean distance had the highest prediction rate with 24.32%, followed by Canberra distance(23.14%) and association strength(21.29%). Conclusions : The weighted Euclidean distance among the vector space measures and the association strength among the probabilistic measures were verified to be the most efficient analysis methods in analyzing the correlation between acupoints and pathologies found in the classical medical texts.

이표본 분포 동일성에 대한 분포무관 검정법 간 검정력 비교 연구 (Power comparison of distribution-free two sample goodness-of-fit tests)

  • 김선빈;이재원
    • 응용통계연구
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    • 제30권4호
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    • pp.513-528
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    • 2017
  • 두 표본 집단이 동일한 분포를 따르는지 비교하기 위해 분포무관 검정이 많이 사용된다. 하지만 여러 검정법을 체계적으로 비교한 연구가 존재하지 않아서 각 검정법의 특성을 고려하여 연구 상황에 맞는 검정법을 선택하기가 어려웠다. 본 연구에서는 이표본 분포 동일성 검정에 해당하는 여러 분포무관 검정법들을 소개하고 체계적인 모의실험을 통해 그 성능을 비교하고자 한다. 두 표본이 각각 (1) 위치, (2) 척도, (3) 왜도, (4) 첨도, (5) 꼬리가중치가 다른 분포에서 추출된 상황에 대해 실험하였다. 실험 결과를 바탕으로 이표본 분포 동일성 검정법 사용에 대한 실용적인 지침을 제시하려고 한다.

Antipruritic Effect of DA-5018m A Capsaicin Derivative, in Mice

  • Kim, Dong-Hwan;Ahn, Byoung-Ok;Kim, Soon-Hoe;Kim, Won-Bae
    • Archives of Pharmacal Research
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    • 제22권6호
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    • pp.549-553
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    • 1999
  • The antipruritic effect of DA-5018m a capsaicin derivative, was examined in mice. Male ICR mice were topically pretreated with Zostrix-HP (0.075% capsaicin cream), 0.1%, 0.3% DA-5018 cream or cream base (control) twice daily for 4 days. One hour after the last application, itch was induced either by compound 48/80 ($50{\mu}g$, s.c.) or leukotriene B4 (0.03 nmol, i.d.) injection into the rostral back of the animals, and the number of scratches made by the animals at the injection site was counted for 60 min post-injection. DA-5018 cream (both 0.1 and 0.3%) significantly inhibited compound 48/80-induced scratching when compared with the cream base control (p<0.01), which Zostrix-HP showed minimal inhibition of the scratching behavior. In leukotriene B4-induced itch model, Zostrix-HP and 0.3% DA-5018 cram significantly inhibited the scratching during the first 10-min period (p<0.01). The results suggest that DA-5018 cream can be used as an antipruritic agent and warrant clinical evaluation.

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식품부패 및 병원성 미생물에 대한 자소잎 추출물의 항균효과 (Antimicrobial Activities of Extracts of Perilla Frutescens Briton var. acuta Kudo on Food Spoilage or Foodborne Disease Microorganisms)

  • 이가순;이주찬;한규흥;오만진
    • 한국식품저장유통학회지
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    • 제6권2호
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    • pp.239-244
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    • 1999
  • 자소잎중 물과 에탄올을 이용하여 얻은 추출물을 2종의 부패곰팡이(Aspergillus flavus KCTC 6143, Aspergillus jlavus KcrC 6961) 및 5종의 식중독세균 ( isteria monocytogenes ATCC 15313, Staphylococc따 aureus 196E ATCC 13565, Escherichia coli 0157:H7 ATCC 43895, Salmonella typhimurium ATCC 13311, Yersinia enterocolitica)에 대하여 항균효과를 조사하였다. 생육증식 저해농도를 disk method로 검색한 결과 에탄올추출물에서 그 효과가 인정되어 5종의 식중독 세균에 대하여 자소잎 에탄올 추출물을 농도별로 첨 가한 후 그 효과를 비교하였다. Gram양성균(L. monocytogenes, S. aureus)의 경우가 Gram음성균(E. coli 0157:H7, S. typhimurium, Y. enterocolitica)에 비하 여자소잎 에탄올추출물에 의한 증식억제효과가 추 출물 $1000\mu\textrm{g}$/mL 농도 첨가구에서 월둥히 컸으며 생 육증식억제효과의 크기는 L. monocytogenes, S. aureus, S. typhimurium의 순이었고, E. coli 0157:H7과 Y enterocolitica균에 대한 생육증식억제 효과는 농도첨 가별에 따라 생육증식이 비례적으로 억제되었다. 자 소잎 에탄올 추출물은 $121^{\circ}C$에서 15분간 가열처리한 후에도 항균력이 인정되었다.

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Effects of musculoskeletal system problems on quality of life and depression in students preparing for university entrance exam

  • Kitis, Ali;Buker, Nihal;Unal, Ayse;Savkin, Raziye
    • The Korean Journal of Pain
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    • 제30권3호
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    • pp.192-196
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    • 2017
  • Background: This study was planned to investigate the relationship between musculoskeletal problems, depression, and quality of life in students preparing for university entrance exams. Methods: A total of 180 students were included in the study, 104 were female (57.77%), and 76 were male (42.22%). Students were reached through the cram schools ("dershane") in Denizli. Musculoskeletal system problems, depression status, and quality of life were determined with the Musculoskeletal-Postural Discomfort Scale (MDS), Boratav Depression Screen Scale (Bordepta), and Short Form-36 (SF-36), respectively. Demographic data, daily study, and sleep duration were also recorded. Results: Students have moderate musculoskeletal discomfort. Musculoskeletal disorders and depressive symptoms are more observed in female students than male students (P = 0.000). The SF-36 results were significantly negatively correlated with the MDS and Bordepta scores. A significant positive correlation was found between musculoskeletal disorders and depression status (r = 0.351, P = 0.000). Sleep duration was negatively correlated with the MDS and Bordepta (r = -0.209, P = 0.005; r = -0.148, P = 0.047, respectively) and positively correlated with the SF-36 role limitation/emotional and social functioning subscales (r = 0.225, P = 0.002 and r = 0.191, P = 0.010 respectively). Conclusions: Musculoskeletal problems and depression status negatively affects general health status especially in female students who are preparing for university entrance examinations. Students should be informed about musculoskeletal problems by healthcare professionals and the study room, tables, and chairs should be arranged ergonomically. Further studies might be determined that why musculoskeletal disorders and depression status are more widely among female students.

목단피 추출물의 항균 및 항산화 작용 (Antimicrobial and Antioxidative Activities from Moutan Cortex Extract)

  • 권오근;손진창;김상철;정신교;박승우
    • 한국식품저장유통학회지
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    • 제5권3호
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    • pp.281-285
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    • 1998
  • 목단피의 메탄을 추출물과 용매 분획물을 이용하여 항균작용, 프리라디칼 소거작용 및 항산화 작용을 검색하고, HPLC와 GC를 이용하여 페놀화합물을 분석하였다. 항균작용은 에칠아세테이트 분획에서 가장 높게 나타났으며, 그람 음성균보다는 그람 양성균에 대하여 더욱 효과적이었다. 에칠아세테이트 분획의 MIC를 측정한 결과, 그람 양성균에 대하여는 156-1250$\mu\textrm{g}$/ml, 그람 음성균에는 2500-5000$\mu\textrm{g}$/ml 이었다. DPPH 라디칼에 대한 프리라디칼 소거활성과 linoleic acid를 이용한 항산화 시험에서도 에칠아세테이트 분획이 가장 높은 활성을 나타내었다. 에칠아세테이트 분획의 항산화 활성은 $\alpha$-tocopherol과 비슷하였다. 에칠아세테이트 분획으로부터 U와 HPLC를 이용하여 3종의 페놀화합물을 확인하였으며, 그 함량은 p-hydroxybenzoic acid 1.35%, methyl gallate 14.61%, gallic acid 4.01% 이었다.

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