• 제목/요약/키워드: partial resistance.

검색결과 442건 처리시간 0.029초

지반조사결과에서 설계변수의 결정문제 -지반특성치 산정을 중심으로- (Determination of Design Parameters from Ground Investigation Results -Focus on geotechnical characteristic values-)

  • 윤길림;윤여원;김홍연
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 추계 학술발표회
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    • pp.126-133
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    • 2008
  • Geotechnical limit state design methods; LRFD of North America is an approach that estimates resistance using design model and then multiplies resistance factor by calculated resistance to reflect the uncertainty of geomaterials and design models; whereas, Eurocode of the Europe employs the partial resistance factor applied directly to each variable in the resistance equation that individual soil properties such as cohesion and angle of internal friction are applied. This discussion paper is a study on characteristic value which has globally been argued through processing of development of Eurocode 7 for geotechnical design even to the present. Estimating the characteristic value of soil properties affects not only determination of design value applied directly to design of geotechnical structures, but also economic feasibility and stability of the structures.

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Effect of environmentally friendly materials on steel corrosion resistance of sustainable UHPC in marine environment

  • Tahwia, Ahmed M.;Elgendy, Gamal M.;Amin, Mohamed
    • Structural Engineering and Mechanics
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    • 제82권2호
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    • pp.133-149
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    • 2022
  • This study investigates the resistance of sustainable ultra-high performance concrete (UHPC) on steel reinforcement corrosion. For enhancing the sustainability of UHPC, concrete mixes were prepared with ordinary Portland cement main binder, and mixes with moderate to high percentages of blast furnace cement (CEM III), fly ash (FA), and slag cement as partial replacements of the full quantity of the used cement. Linear polarization resistance technique was employed to estimate the electrochemical behavior of the concrete specimens. Results showed that the compressive strength and the resistance of steel to corrosion in marine environments can be enhanced by improving the sustainability of UHPC through incorporation of CEM III, FA, and slag cement. FA replacement of up to 50% with the addition of 15% SF content produced better compressive strength and steel corrosion resistance than slag cement whether with the use of ordinary Portland cement or blast furnace cement as the main binder.

스마트폰 채택 및 지속사용에 있어 사용자 저항과 사회적 영향력의 역할에 대한 탐색연구 (Exploring the Roles of User Resistance and Social Influences on Smartphone Acceptance and Continuous Usage)

  • 최새솔;유재흥
    • Journal of Information Technology Applications and Management
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    • 제19권4호
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    • pp.41-59
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    • 2012
  • This study examines the roles of user resistance and social influences on the acceptance and continuous usage of smartphones at different stages of adoption. The respondents were classified into three groups according to their innovation adoption stage : non-user group, the potential user group and the trial user group. Theories relevant to user resistance, social influences including normative social influences and informational social influences, as well as user adoption and continuance behavior were reviewed and integrated into our research model. In order to verify the proposed structured equation model, we conducted an online survey by targeting mobile phone users and collected data to be analyzed through a partial least squares (PLS) test. This study tested whether there exists differences in the effects of user resistance and different types of social influence on user's adoption or continuance intetion among these three groups. The results showed that user resistance exists in all adopter groups and that it has significant negative influences on intention to use a smartphone. The findings also revealed that user resistance can be enhanced or resolved by two types of social influence; informational social influence resolves user resistance regardless of the adopter category, while normative social influence enhances the user resistance of potential users. Furthermore, the findings show that social influence regardless of the type positively affects user intention. Several theoretic and practical implications pertaining to the results are discussed.

금속 Alkoxide를 이용한 LAS계 내열세라믹스의 제조에 관한 연구(I) (Preparation of the LAS Ceramics for Heat Resistance using Metal Alkoxide (I))

  • 김형태;이응상
    • 한국세라믹학회지
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    • 제30권12호
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    • pp.987-992
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    • 1993
  • In order to synthesize the heat resistance ceramics of LAS system, we studied on preparing the fine powder with homogeneity by sol-gel method using metal alkoxide. Various results were obtained depending on the composition and process. When the amount of H2O added at initial stage is higher than 10mol/$\ell$, and when the amount of catalyst is 0.1mol/$\ell$, the particle size of synthesized hydrate becomes finer. On condition that partial prehydrolysis time of TEOS is more than 50 hours, the monosized fine powder is obtained(below 1${\mu}{\textrm}{m}$).

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합성반강접 CFT기둥-보 접합부 구조의 경제성 평가 (The Structural Economical Efficiency Evaluation of Partially Restrained Composite CFT Column-to-Beam Connection)

  • 김선희;방중석;박영욱;최성모
    • 한국강구조학회 논문집
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    • 제24권1호
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    • pp.109-117
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    • 2012
  • 연구대상은 콘크리트 충전강관 (Concrete Filled steel tube)기둥과 보의 접합부를 합성반강접으로 적용한 구조물의 설계 적용에 관한 것이다. 합성반강접으로 기둥접합부의 강성을 조절함으로서 구조적 안전성을 확보하고 경제적인 부재를 적용하고자 하였다. 저층건물을 모멘트골조로 구조물의 안정성을 검토한 결과 합성작용으로 인하여 합성반강접을 이용하면 횡강성이 증대하여 저층건물의 경우 특별한 횡 보강재 없이 저항할 수 있음을 확인 하였다. 고층건물의 경우 모멘트골조가 횡저항 분담이 10%정도 되었으며 반강접 비율은 60%정도가 적절하였다. 경제적인 면에서 보 부재는 등분포하중이 작용하는 경우는 반강접 효과가 크나 집중하중이 작용하는 보는 반강접 효과가 크지 않았으며 등분포의 경우 60% 반강접이 단부 모멘트 저감에 따른 경제성이 가장 좋은 것으로 분석되었다. 단부 모멘트는 약 25% 감소되는 것을 확인 할 수 있었다.

Partial SOI 기판을 이용한 고속-고전압 Smart Power 소자설계 및 전기적 특성에 관한 연구 (Design of a New Smart Power ICs based on the Partial SOI Technology for High Speed & High Voltage Applications)

  • 최철;구용서;안철
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(2)
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    • pp.249-252
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    • 2000
  • A new Smart rower IC's based on the Partial SOI technology was designed for such applications as mobile communication systems, high-speed HDD systems etc. A new methodology of integrating a 0.8${\mu}{\textrm}{m}$ BiCMOS compatible Smart Power technology, high voltage bipolar device, high speed SAVEN bipolar device, LDD NMOSFET and a new LDMOSFET based on the Partial SOI technology is presented in this paper. The high voltage bipolar device has a breakdown voltage of 40V for the output stage of analog circuit. The optimized Partial SOI LDMOSFET has an off-state breakdown voltage of 75 V and a specific on- resistance of 0.249mΩ.$\textrm{cm}^2$ with the drift region length of 3.5${\mu}{\textrm}{m}$. The high-speed SAVEN bipolar device shows cut-off frequency of about 21㎓. The simulator DIOS and DESSIS has been used to get these results.

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Selective Laser Melting을 이용한 코발트-크롬 가철성 국소의치의 수복 증례 (Cr-Co removable partial denture treatment fabricated by selective laser melting: a case report)

  • 임지훈;신수연
    • 구강회복응용과학지
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    • 제37권1호
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    • pp.39-47
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    • 2021
  • 의치의 금속구조물을 selective laser melting을 통하여 제작하는 경우 기존의 제작 방식에 비해 여러 기공 과정이 생략되어 시간이 절약되고 간편해진다. 또한 균질한 밀도의 금속구조물을 얻을 수 있어 우수한 기계적 성질, 특히 피로 파절에 대한 높은 저항성을 기대할 수 있다. 본 증례에서는 부분 무치악 환자에서 기존의 방식으로 최종인상을 채득하여 주모형을 제작하였고 이를 스캔하여 데이터화 하였다. 스캔 데이터 상에서 금속구조물을 디자인한 뒤 selective laser melting 방식으로 가철성 국소의치를 제작하였으며 기능적 및 심미적으로 만족스러운 결과를 보였기에 이를 보고하는 바이다.

인공 해수 간헐 조건에서의 방청제 및 혼화재를 사용한 콘크리트 압축강도 및 저항의 특성 (The characteristics of compressive strength resistance of concrete combined with corrosion inhibitors and mineral admixtures under simulated tidal condition)

  • 이용은;장태순;양우석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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    • pp.641-646
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    • 1998
  • The structures exposed to marine environment do not show long-term durability due to corrosion of steel and deterioration of concrete by the attack of various salts dissolved in sea water. In this study, Partial substitution of cement with fly ash(20%) or blast furnace slag(40%) was made together with the addition of 4 different corrosion-inhibitors, as a protective measure of concrete structures against chemical attack of salts. Combined effects of mineral and corrosion-inhibiting admixtures were tested by measuring the resistance and compressive strength of concretes under the simulated tidal condition, which consists of alternating 12 hour periods of immersion in artificial sea water and drying in air. Both the strength and concrete resistance were found to decrease in following order, regardless of the corrosion inhibitors the concretes with blast furnace slag, those with fly ash and those without any mineral admixtures. The interrelation between compressive strength of concrete and resistance was investigated.

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Establishment and Partial Characterization of an Epirubicin-Resistant Gastric Cancer Cell Line with Upregulated ABCB1

  • Felipe, Aledson Vitor;Moraes, Andrea Aparecida;de Oliveira, Juliana;da Silva, Tiago Donizetti;Forones, Nora Manoukian
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권16호
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    • pp.6849-6853
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    • 2014
  • Multidrug resistance (MDR) is a major impediment to successful chemotherapy of gastric cancer. Our aim was to establish an epirubicin-resistant cell subline (AGS/EPI) and to elucidate the mechanisms involved in acquired EPI resistance. The AGS/EPI cell subline developed by exposing parental AGS cells to stepwise increasing concentrations of EPI demonstrated 2.52-fold resistance relative to the AGS cell line, and mRNA expression of the ATP-dependent drug-efflux pump P-glycoprotein (Pgp), more recently known as ABCB1 protein, was similarly upregulated. An AGS/EPI cell subline could thus be effectively established, and MDR mechanism of these cells was shown to be related to the overexpression of mRNA of the ABCB1 gene.