• 제목/요약/키워드: EBR

검색결과 37건 처리시간 0.029초

배무채 에탄올층의 D-galactosamine 간손상에 대한 보호효과 (Hepatoprotective Effect of Ethanol Extract of xBrassicaraphanus on Liver Injury in Rats Treated by D-galactosamine)

  • 이연희;이은옥;이효정;심범상;안규석;최종원;이수성;윤병수;김성훈
    • 동의생리병리학회지
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    • 제21권6호
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    • pp.1388-1393
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    • 2007
  • The protective effect of xBrassicoraphanus (BR) on liver inhury was evaluated in the rats with liver injury induced by i.p. injection of D-galactosamine (GalN) following 2 week oral treatment of ethanol extract of xBrassicoraphanus (EBR). EBR (200 mg/kg) significantly suppressed the levels of ALT, AST, SDH, ${\gamma}-GT$, ALP, LDH and lipid peroxidation compared with GalN treated control, while EBR at 100 mg/kg significantly suppressed AST and ${\gamma}-GT$. Similarly, EBR at 200 mg/kg significantly attenuated the levels of Phase I enzymes such as XO, AO, AH and AD as well as significantly increased the levels of Phase II enzymes such as SOD, catalase and GSH-Px in the GalN treated rats. Taken together, these results indicate that the ethanol extract of xBrassicoraphanus may have a hepatoprotective effect against GalN induced liver injury, suggesting the ethanol extract of xBrassicoraphanus can be applied as hepatoprotective functional food. However, its mechanism should be further studied in molecular and cellular view points.

Verification of SARAX code system in the reactor core transient calculation based on the simplified EBR-II benchmark

  • Jia, Xiaoqian;Zheng, Youqi;Du, Xianna;Wang, Yongping;Chen, Jianda
    • Nuclear Engineering and Technology
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    • 제54권5호
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    • pp.1813-1824
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    • 2022
  • This paper shows the verification work of SARAX code system in the reactor core transient calculation based on the simplified EBR-II Benchmark. The SARAX code system is an analysis package developed by Xi'an Jiaotong University and aims at the advanced reactor R&D. In this work, a neutron-photon coupled power calculation model and a spatial-dependent reactivity feedback model were introduced. To verify the models used in SARAX, the EBR-II SHRT-45R test was simplified to an ULOF transient with an input flowrate change curve by fitting from reference. With the neutron-photon coupled power calculation model, SARAX gave close results in both power fraction and peak power prediction to the reference results. The location of the hottest assembly from SARAX and reference are the same and the relative power deviation of the hottest assembly is 2.6%. As for transient analysis, compared with experimental results and other calculated results, SARAX presents coincident results both in trend and absolute value. The minimum value of core net reactivity during the transient agreed well with the reported results, which ranged from -0.3$ to -0.35$. The results verify the models in SARAX, which are correct and able to simulate the in-core transient with reliable accuracy.

Effects of Filler Types and Content on Shrinkage Behavior of Polypropylene Composites

  • Jung, Chun-Sik;Hwang, Seok-Ho
    • Elastomers and Composites
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    • 제57권3호
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    • pp.107-113
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    • 2022
  • The effects of fillers [talc, calcium carbonate, glass fiber, and EBR (ethylene-butene rubber)] on the shrinkage and mechanical properties of injection-molded polypropylene composites were investigated. The shrinkage correlated with the shape of the filler particles: at the same amount added, glass fibers with a large aspect ratio had the greatest effect on the shrinkage of polypropylene composites, followed by flake-shaped talc and granular calcium carbonate. It was confirmed that the addition of EBR rubber as an impact strength modifier reduced shrinkage proportionally to the added content. In addition, the addition of glass fiber resulted in the greatest increases in tensile and flexural strengths.

임의의 사각형 QAM의 일반화된 비트 오율 분석 (Generalized BER Analysis of Arbitrary Rectangular QAM)

  • 윤동원;조경국;서기범
    • 한국통신학회논문지
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    • 제27권10A호
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    • pp.962-968
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    • 2002
  • 무선통신 환경의 한정된 주파수 자원에서 신뢰성 있는 고속의 통신방식이 요구되고 있다. 직교 진폭 변조 (QAM) 는 대역폭의 증가없이 고속의 데이터 처리가 가능한 유용한 변조 방식이다. 이제까지 사각형(rectangular) 직교 진폭 변조 (R-QAM) 신호의 일반화된 BER 식은 유도된바 없다. 이 논문에서는 가산성 백색 가우시안 잡음 환경에서 그레이 부호화된 R-QAM의 일반화된 closed-from 형태의 EBR식을 유도하고 분석한다. 먼저 I-ary PAN 신호에 대하여 Irk 4, 8, 16 일 때의 유도하고 이 결과들로부터 유도 과정의 규칙성을 찾아내며, 그 규칙성들로부터 임의의 I-ary PAM 신호에 대한 일반화된 BER 식을 유도한다. R-QAM 신호는 각각 독립적인 동상 성분의 I-ary PAM 과 직교 성분의 J-ary PAM으로 구성되기 때문에 I-ary PAM 의 일반화된 BER 식으로부터 R-QAM 신호에 대한 일반화된 BER 식을 구한다. 또한 SNR이 높을 때에 지배적인 항을 고려한 간단한 근사식도 유도한다.

AFRP로 보강된 철근콘크리트 보의 휨 거동과 연성도 평가 (Evaluation of Behavior and Ductility of Reinforced Concrete Beams Strengthened With AFRP)

  • 김준원;김태완;홍성남;박선규
    • 한국구조물진단유지관리공학회 논문집
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    • 제13권2호통권54호
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    • pp.206-214
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    • 2009
  • FRP는 재료가 가지고 있는 특성 때문에 최근 들어 미국, 일본 등에서 보강 재료로 널리 쓰이고 있으며 우리나라에서도 활발한 연구가 이루어지고 있다. 본 연구에서는 EBR, NSMR 보강공법을 사용하는 동시에 AFRP의 종류와 보강면적을 다르게 보강하여 각 실험체의 거동과 연성을 평가하였다. 보강면적을 증가시킨 경우가장 큰 하중증가를 보였으나 취성적인 파괴 양상을 띠었으며 미성숙파괴가 일어났다. 공법면에서는 NSMR공법으로 보강하는 것이 더 효율적인 것으로 나타났으며 보강재료 표면의 요철이 연성파괴를 유도하는 것으로 나타났다.

데이터 그리드 환경에서 파일 교체 정책 연구 (A Study of File Replacement Policy in Data Grid Environments)

  • 박홍진
    • 정보처리학회논문지A
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    • 제13A권6호
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    • pp.511-516
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    • 2006
  • 데이터 그리드는 대용량의 데이터 어플리케이션 처리를 위해 지리적으로 분산되어 있는 저장 자원을 제공한다. 대용량을 처리해야 하는 데이터 그리드 환경에서는 기존 웹 캐싱 정책이나 가상 메모리 캐쉬 교체 정책과는 다른 파일 교체 정책이 필요하다. LRU(Least Recently Used)나 LCB-K(Least Cost Beneficial based on K), EBR(Economic-based cache replacement), LVCT(Least Value-based on Caching Time) 같은 기존의 파일 교체 전략은 파일 교체를 위해 추가적인 자원이 필요하거나 미래를 예측해야한다. 본 논문은 이를 해결하기 위해 파일의 크기에 기반하여 파일 교체를 수행하는 SBR-k(Sized-based replacement-k)을 제안한다. 성능평가 결과 제안한 정책이 기존의 정책보다 더 나은 성능을 나타낸다는 것을 확인하였다.

Experimental study on effect of EBRIG shear strengthening method on the behavior of RC beams

  • Shomali, Amir;Mostofinejad, Davood;Esfahani, Mohammad Reza
    • Advances in concrete construction
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    • 제8권2호
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    • pp.145-154
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    • 2019
  • The present experimental study addresses the structural response of reinforced concrete (RC) beams strengthened in shear. Thirteen RC beams were divided into four different sets to investigate the effect of transverse and longitudinal steel reinforcement ratios, concrete compressive strength change and orientation for installing carbon fiber-reinforced polymer (CFRP) laminates. Then, we employed a shear strengthening solution through externally bonded reinforcement in grooves (EBRIG) and externally bonded reinforcement (EBR) techniques. In this regard, rectangular beams of $200{\times}300{\times}2000mm$ dimensions were subjected to the 4-point static loading condition and their load-displacement curves, load-carrying capacity and ductility changes were compared. The results revealed that using EBRIG method, the gain percentage augmented with the increase in the longitudinal reinforcement ratio. Also, in the RC beams with stirrups, the gain in shear strength decreased as transverse reinforcement ratio increased. The results also revealed that the shear resistance obtained by the experimental tests were in acceptable agreement with the design equations. Besides, the results of this research indicated that using the EBRIG system through vertical grooves in RC beams with and without stirrups caused the energy absorption to increase about 85% and 97%, respectively, relative to the control.

Shear strengthening of deficient concrete beams with marine grade aluminium alloy plates

  • Abu-Obeidah, Adi S.;Abdalla, Jamal A.;Hawileh, Rami A.
    • Advances in concrete construction
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    • 제7권4호
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    • pp.249-262
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    • 2019
  • In this study, high strength aluminum alloys (AA) plates are proposed as a new construction material for strengthening reinforced concrete (RC) beams. The purpose of this investigation is to evaluate AA plate's suitability as externally bonded reinforcing (EBR) materials for retrofitting shear deficient beams. A total of twenty RC beams designed to fail in shear were strengthened with different spacing and orientations. The specimens were loaded with four-points loading till failure. The considered outcome parameters included load carrying capacity, deflection, strain in plates, and failure modes. The results of all tested beams showed an increase up to 37% in the load carrying capacity and also an increase in deflection compared to the control un-strengthened beams. This demonstrated the potential of adopting AA plates as EBR material. Finally, the shear contribution from the AA plates was predicted using the models available in the ACI440-08, TR55 and FIB14 design code for fiber reinforced polymer (FRP) plates. The predicted results were compared to experimental testing data with the ratio of the experimentally measured ultimate load to predicted load, range on the average, between 93% and 97%.

Two step lithography와 나노 실리카 코팅을 이용한 초발수 필름 제작 (Fabrication of Superhydrophobic Film with Uniform Structures Using Two Step Lithography and Nanosilica Coating)

  • 유채린;이동원
    • 센서학회지
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    • 제28권4호
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    • pp.251-255
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    • 2019
  • We propose a two-step lithography process to minimize edge-bead issues caused by thick photoresist (PR) coating. In the conventional PR process, the edge bead can be efficiently removed by applying an edge-bead removal (EBR) process while rotating the silicon wafer at a high speed. However, applying conventional EBR to the production of desired PR mold with unique negative patterns cannot be used because a lower rpm of spin coating and a lower temperature in the soft bake process are required. To overcome this problem, a two-step lithography process was developed in this study and applied to the fabrication of a polydimethylsiloxane (PDMS) film having super-hydrophobic characteristics. Following UV exposure with a first photomask, the exposed part of the silicon wafer was selectively removed by applying a PR developer while rotating at a low rpm. Then, unique PR mold structures were prepared by employing an additional under-exposure process with a second mask, and the mold patterns were transferred to the PDMS. Results showed that the fabricated PDMS film based on the two-step lithography process reduced the height difference from 23% to 5%. In addition, the water contact angle was greatly improved by spraying of hydrophobic nanosilica on the dual-scaled PDMS surface.

SBR-k(Sized-based replacement-k) : 데이터 그리드 환경에서 파일 교체 (SBR-k(Sized-base replacement-k) : File Replacement in Data Grid Environments)

  • 박홍진
    • 한국콘텐츠학회논문지
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    • 제8권11호
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    • pp.57-64
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    • 2008
  • 데이터 그리드는 대용량의 데이터 어플리케이션 처리를 위해 지리적으로 분산되어 있는 저장 자원을 제공한다. 대용량을 처리해야 하는 데이터 그리드 환경에서는 기존 웹 캐싱 정책이나 가상 메모리 캐쉬 교체 정책과는 다른 파일 교체 정책이 필요하다. LRU(Least Recently Used)나 LCB-K(Least Cost Beneficial based on K), EBR(Economic-based cache replacement), LVCT(Least Value-based on Caching Time) 같은 기존의 파일 교체 전략은 파일 교체를 위해 추가적인 자원이 필요하거나 미래를 예측해야한다. 본 논문은 이를 해결하기 위해 파일의 크기에 기반하여 파일 교체를 수행하는 SBR-k(Sized-based replacement-k)을 제안한다. 제안된 정책은 불확실한 미래 예측의 부담을 줄이고, 요청된 파일에 대응되는 교체 파일의 개수가 적게 하이 위해 파일 크기를 고려하였다. 성능평가 결과 캐쉬 크기가 작은 경우에 적중률이 비슷하나 캐쉬 크기가 크면 본 논문에서 제시한 정책이 우수함을 보였다.