• Title/Summary/Keyword: Cooper

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A Study on Strength and Permeability of Cooper Slag mixed Porous Concrete (동제련 슬래그를 혼입한 포러스 콘크리트의 강도 및 투수성능에 관한 연구)

  • Shim, Byung-Ju;Kim, Young-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.05a
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    • pp.69-72
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    • 2011
  • The purpose of this study is to identify basic property of porous concrete using cooper slag as fine aggregate. The specimens were made with cooper slag with various mixing ratio(10, 20, 30, 50%), porous concrete and porous concrete containing river fine aggregate and crushed fine aggregate, which W/B ratio fixed 0.25. Compressive strength, Flexural strength, coefficient of permeability. From the test results, various fine aggregate mixing ratio improves compressive strength and flexural strength, but cooper slag fine aggregate mixing ratio over 20%, concrete indicates trend to decrease performance of permeability. Concrete containing fine aggregate is improved the performance of permeability and strength compared to other specimen, when age 28days, and cooper slag mixing ratio less than 20% concrete indicates better performance than cooper slag mixing ratio 20% over.

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Oscillation of Critical Current by Gate Voltage in Cooper Pair Transistor (Cooper pair transistor에서 gate voltage에 의한 임계전류의 진동)

  • Song, W.;Chong, Y.;Kim, N.
    • Progress in Superconductivity
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    • v.11 no.2
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    • pp.158-161
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    • 2010
  • We measured the critical current of a Cooper pair transistor consisting of two Josephson junctions and a gate electrode. The Cooper pair transistors were fabricated by using electron-beam lithography and double-angle evaporation technique. The Gate voltage dependence of critical current was measured by observing voltage jumps at various gate voltages while sweeping bias current. The observed oscillation was 2e-periodic, which shows the Cooper pair transistor had low level of quasiparticle poisoning.

Physical Properties of Concrete mixed with Fine Sand and Copper Slag (동슬래그 혼합 잔골재를 이용한 콘크리트의 물리적 특성)

  • 이진우;김경민;배연기;이재삼
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.15-18
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    • 2003
  • Development of the construction industry generally exhausts natural aggregate. Hence it is problem to the lack of supply and quality deterioration, so the resource saving and protection of environment is made an effort through recycling by-product. This study presents that fundamental properties of concrete which used cooper slag as alternate sand of low fineness modulus and plan of cooper slag as concrete aggregate. Testing factors are concrete's slump, air contents, unit weight and compressive strength. The results of this study are as follows; (1) Concrete slump is generally satisfied with the condition but is inferior to the others in substitution rates 30%. Also air contents are 3.1-4.1% and go up according to increase substitution rate. (2) Unit weight increase in 1.1% as the mixing ratio of cooper slag argument 10%. (3) compressive strength of cooper slag concrete is similar to plain and especially higher 11-15% in W/C 45%, 50%. So it seems that aggregate mixed cooper slag is suitable to low water-cement ratio mixture.

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A Study on Sun Yung Shin's Literature (신선영(Sun Yung Shin) 문학 연구)

  • Yoo, Jin Wol
    • Cross-Cultural Studies
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    • v.21
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    • pp.139-164
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    • 2010
  • Sung Yung Shin was adopted as a Korean infant to an American family. She is now one of the most important writers in Asian American literary field. This paper analyzes the characteristics of her literature, focusing on Skirt full of Black (poetry)and Cooper's Lesson(children's book). Sun Yung Shin uses collage in Skirt full of Black as an effective rhetorical device because it can express her experience as an adopted other in the multicultural American society. She rewrites the fairy tale of Swan Prince in the viewpoint of silence. For a yellow Asian adopted woman, speaking is suppressed. In the end, the attempt to escape from silence is the writer's resisting activity, and the rewriting of the tale is her questioning in place of the princess. I analyses Cooper's Lesson in the viewpoint of transcultural assimilation. Cooper's lesson is accomplished not by his white father but by a Korean settler, Mr. Lee. Cooper's family is a hybrid composed of white American father, Korean mother, and their half son. So this family has many complicated difficulties, though it's small. Mr. Lee who accepted a new language to establish a new identity teaches Cooper the importance of cultural assimilation, which is not a one-sided integration to dominant culture but an intercultural communion while sustaining each culture's singularity. Cooper learns that he should live in an harmonious and balanced life in a multi-cultural society while keeping his own subjective point of view.

EGS field case studies - UK Rosemanowes and Australian Cooper Basin projects (EGS 실증연구사례 - 영국 Rosemanowes 프로젝트와 호주 Cooper Basin 프로젝트)

  • Min, Ki-Bok;Xie, Linmao;Kim, Hanna;Lee, Jaewon
    • Tunnel and Underground Space
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    • v.24 no.1
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    • pp.21-31
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    • 2014
  • In order to generate electricity from geothermal energy for non-volcanic region, the concept of enhanced geothermal system (EGS) is introduced which forms an artificial reservoir by injecting high pressure fluid to 5 km deep and circulating geothermal fluid through the reservoir. Demonstration studies have been conducted in various countries and regions for determining the feasibility of EGS. In this technical note, experiences, errors, and implications of EGS demonstration projects in UK Rosemanowes and Australia Cooper Basin which have been carried out since 2002 are introduced to be used for the EGS demonstration project in Korea.

A Pilot Study Exploring Temporal Development of Gut Microbiome/Metabolome in Breastfed Neonates during the First Week of Life

  • Imad Awan;Emily Schultz;John D. Sterrett;Lamya'a M. Dawud;Lyanna R. Kessler;Deborah Schoch;Christopher A. Lowry;Lori Feldman-Winter;Sangita Phadtare
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.26 no.2
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    • pp.99-115
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    • 2023
  • Purpose: Exclusive breastfeeding promotes gut microbial compositions associated with lower rates of metabolic and autoimmune diseases. Its cessation is implicated in increased microbiome-metabolome discordance, suggesting a vulnerability to dietary changes. Formula supplementation is common within our low-income, ethnic-minority community. We studied exclusively breastfed (EBF) neonates' early microbiome-metabolome coupling in efforts to build foundational knowledge needed to target this inequality. Methods: Maternal surveys and stool samples from seven EBF neonates at first transitional stool (0-24 hours), discharge (30-48 hours), and at first appointment (days 3-5) were collected. Survey included demographics, feeding method, medications, medical history and tobacco and alcohol use. Stool samples were processed for 16S rRNA gene sequencing and lipid analysis by gas chromatography-mass spectrometry. Alpha and beta diversity analyses and Procrustes randomization for associations were carried out. Results: Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria were the most abundant taxa. Variation in microbiome composition was greater between individuals than within (p=0.001). Palmitic, oleic, stearic, and linoleic acids were the most abundant lipids. Variation in lipid composition was greater between individuals than within (p=0.040). Multivariate composition of the metabolome, but not microbiome, correlated with time (p=0.030). Total lipids, saturated lipids, and unsaturated lipids concentrations increased over time (p=0.012, p=0.008, p=0.023). Alpha diversity did not correlate with time (p=0.403). Microbiome composition was not associated with each samples' metabolome (p=0.450). Conclusion: Neonate gut microbiomes were unique to each neonate; respective metabolome profiles demonstrated generalizable temporal developments. The overall variability suggests potential interplay between influences including maternal breastmilk composition, amount consumed and living environment.

Hydraulic Parameter Estimation of a Granite Area Using Slug Tests (순간충격시험에 의한 화강암지역의 수리적 매개변수 산출)

  • 함세영;김문수;성익환;이병대;김광성
    • The Journal of Engineering Geology
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    • v.11 no.1
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    • pp.63-79
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    • 2001
  • This study is aimed for estimating hydraulic parameters using the Cooper-Bredehoeft-Papadopulos, the Hvorslev, and the Bouwer & Rice methods at nineteen test holes in Me. Geumjeong area composed of Bulguksa granites, and for characterizing hydraulic properties at the test holes with relatioll to drill core data. The relation among hydraulic Dammeters obtained by the three methods is also considered. The study area is divided into four sub-areas to consider the hydraulic characteristics. The difference of hydraulic conductivity estimates between the injection and the withdrawal slug test may be due to penncable fracture distlibutions around the test hole and/or the disturbance of fine mateIials in the fractures induced by the pressure variation due to different mechanisms of test initiation. The hydraulic conductivity estimates detennined by the Cooper-Bredehoeft-Papadopulos, the Hvorslev and the Bouwer & Rice methods ranges from 10$^{-8}$ to lO$^{-5}$m/sec, and the ranges of average values are from 10$^{-7}$ to 10$^{-6}$m/sec. Also, the transmissivity ranges from 10$^{-7}$ to 10$^{-5}$$m^2$/sec. Comparing average hydraulic conductivity by the Cooper-Bredehoeft-Papadopulos, the Hvorslev and the Bouwer & Rice methods, by the Hvorslev method has the highest values, then the Bouwer & Rice method, and the Cooper-Bredehoeft-Papadopulos method has the lowest.

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