• 제목/요약/키워드: resistance model

검색결과 3,373건 처리시간 0.04초

Nonlinear analysis of finite beam resting on Winkler foundation with consideration of beam-soil interface resistance effect

  • Zhang, L.;Zhao, M.H.;Xiao, Y.;Ma, B.H.
    • Structural Engineering and Mechanics
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    • 제38권5호
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    • pp.573-592
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    • 2011
  • Comprehensive and accurate analysis of a finite foundation beam is a challenging engineering problem and an important subject in foundation design. One of the limitation of the traditional Winkler elastic foundation model is that the model neglects the effect of the interface resistance between the beam and the underneath foundation soil. By taking the beam-soil interface resistance into account, a deformation governing differential equation for a finite beam resting on the Winkler elastic foundation is developed. The coupling effect between vertical and horizontal displacements is also considered in the presented method. Using Galerkin method, semi-analytical solutions for vertical and horizontal displacements, axial force, shear force and bending moment of the beam under symmetric loads are presented. The influences of the interface resistance on the behavior of foundation beam are also investigated.

플랫 플레이트 내부 접합부의 강도산정모델 (Strength Prediction Model for Flat Plate-Column Connections)

  • 최경규;박홍근;안귀용
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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    • pp.897-902
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    • 2002
  • The failure of flat plate connection is successive failure process accompanying with stress redistribution, hence it is necessary to compute the contributions of each resistance components at ultimate state. In the present study, the interactions of resultant forces at each faces of connection, i.e. shear, bending moment and torsional moment are considered in the assessment of strength of slab. As a result the strength prediction model for connection is made up as combination of bending resistance, shear resistance and torsional resistance. The proposed method is verified by the experimental data and numerical data of continuous slabs.

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수조모델 실험에 의한 접지저항 추정 (presumption of Earth Resistance by Water Tank Model)

  • 고희석;최종규;김주찬;이충식
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2002년도 학술대회논문집
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    • pp.125-131
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    • 2002
  • It is very important to assume potential distribution to be generated in electrode environs and grounding resistance by current beforehand, when incoming at grounding electrode to plan efficient grounding facilities In this paper, we analyzed grounding resistance through a simulation experiment by a water tank scaled model electrode of the rectangular earth plate, a theoretical Calculation result of the rectangular earth plate and measurement of grounding resistance buried rectangular earth plate analysing earth surface potential.

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건축물기초 접지극의 비교 분석에 관한 연구 (Research for a comparison an analysis of grounding electrode in the Foundation of building)

  • 김성삼;김주찬;이충식;고희석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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    • pp.271-273
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    • 2005
  • In this paper, The experiment is performed for using reinforced building of foundation as a down conductor and a substitutional earth electrode. It is shown that earth resistance is influenced by mortar block resistance and concrete resistance more than the change of the resistance which is about steel reinforcing volume in all of the mortar block model and concrete block model.

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Investigation of Spudcan Penetration Resistance in Layered Soil Deposits

  • Jan, Muhammad Asad;Nizamani, Zubair Ahmed;Park, Duhee
    • 한국지반환경공학회 논문집
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    • 제22권1호
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    • pp.13-20
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    • 2021
  • A suite of 3D large deformation finite element (FE) analyses was performed to investigate the load transfer mechanism and penetration resistance of spudcan foundations in heterogeneous soil profile consisting of sand and clay. The Elasto-Plastic models following Mohr-Coulomb and Tresca failure criteria were adopted for sand and clay, respectively. The accuracy of the numerical model was validated against centrifuge test measurements. The dense sand behavior with dilation is modeled using the non-associated flow rule. An investigation study consisting of key parameters, which includes variation in soil stratigraphy (sand-clay, sand-clay-sand), strength parameters of sand and clay (��' and su) and normalized height ratio of the sand layer (Hs/D) was conducted to assess the penetration behavior of spudcan. Based on calculated outputs, it was demonstrated that these parameters have a significant influence on the penetration resistance of spudcan. The calculated penetration resistance profiles are compared with the published (sand overlying clay) analytical model. It is confirmed that for the case of two-layer soil, the available theoretical model provides an accurate estimate of peak penetration resistance (qpeak). In the case of three-layer soil, the presence of a third stiff layer affects the penetration resistance profile due to the squeezing of the soil.

Hemodynamics of a Connecting conduit Between the Left Ventricle and the Left Decending Coronary Artery

  • Shim, Eun-Bo;Sah, Jong-Yub
    • International Journal of Vascular Biomedical Engineering
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    • 제1권2호
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    • pp.20-29
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    • 2003
  • A new treatment for coronary artery occlusive disease is being developed in which a shunt or conduit is placed directly connecting the left ventricle with the diseased artery at a point distal to the obstruction. To aid in assessing and optimizing its benefit, a computational model of the cardiovascular system was developed and used to explore various design conditions. Simulation results indicate that in complete LAD occlusion, flow can be returned to approximately 65% of normal if the conduit resistance is equal for forward and reverse flow, increasing to 80% in the limit in which backflow resistance is infinite. Increases in flow rate produced by asymmetric flow resistance are considerably enhanced in the case of a partial LAD obstruction since the primary effect of resistance asymmetry is to prevent leakage back into the ventricle("steal") during diastole. Increased arterial compliance has little effect on net flow with a symmetric shunt, but leads to considerable augmentation when the resistance is asymmetric. These results suggest that an LV-LAD conduit will be beneficial when stenosis resistance(Rst) > 27 PRU if resistance is symmetric.

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Pt 나노입자가 분산된 SiO2 박막의 저항-정전용량 관계 (Relation between Resistance and Capacitance in Atomically Dispersed Pt-SiO2 Thin Films for Multilevel Resistance Switching Memory)

  • 최병준
    • 한국재료학회지
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    • 제25권9호
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    • pp.429-434
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    • 2015
  • Resistance switching memory cells were fabricated using atomically dispersed Pt-$SiO_2$ thin film prepared via RF co-sputtering. The memory cell can switch between a low-resistance-state and a high-resistance-state reversibly and reproducibly through applying alternate voltage polarities. Percolated conducting paths are the origin of the low-resistance-state, while trapping electrons in the negative U-center in the Pt-$SiO_2$ interface cause the high-resistance-state. Intermediate resistance-states are obtained through controlling the compliance current, which can be applied to multi-level operation for high memory density. It is found that the resistance value is related to the capacitance of the memory cell: a 265-fold increase in resistance induces a 2.68-fold increase in capacitance. The exponential growth model of the conducting paths can explain the quantitative relationship of resistance-capacitance. The model states that the conducting path generated in the early stage requires a larger area than that generated in the last stage, which results in a larger decrease in the capacitance.

스마트폰 사용자가 모바일뱅킹을 사용하지 않는 이유: 소극적 저항과 적극적 저항의 차이를 중심으로 (Why Smartphone Users are Not Using Mobile Banking: Focusing on the Difference between Passive Resistance and Active Resistance)

  • 김종기;김지윤
    • 한국정보시스템학회지:정보시스템연구
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    • 제27권3호
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    • pp.81-102
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    • 2018
  • Purpose The purpose of this study is to investigate the reason why smartphone users do not use mobile banking based on Status Quo Bias and to find out whether there is a difference between passive resistance and active resistance. Design/methodology/approach This study made a design of the research model based on Status Quo Bias. SPSS 23.0 and SmartPLS 2.0 were used for the analysis. Multiple group analysis was performed to identify differences between groups. Findings According to the empirical analysis result, this study confirmed that inertia and perceived risk affected smartphone users who do not use mobile banking. According to the type of resistance, the active resistance group(64.2%) was more than the passive resistance group(35.8%), and it was confirmed that there was a difference in the reasons for not using mobile banking between passive and active resistance group. That is, the greatest difference between passive and active resistance groups was found to be perceived risk, which is an assessment of risk.

혁신특성과 사용자특성이 전자책 수용에 미치는 영향 : 혁신저항모형을 중심으로 (Effects of Innovation Characteristics and User Characteristics on the Adopting e-Books : Focused on Innovation Resistance Model)

  • 윤수경;김명지;최준호
    • 한국콘텐츠학회논문지
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    • 제14권8호
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    • pp.61-73
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    • 2014
  • 기존의 전자책 연구들이 이용과 충족 이론과 기술수용모형 중심으로 이루어졌던 반면, 본 논문은 전자책의 확산을 어렵게 만드는 원인을 혁신저항모형을 토대로 분석하였다. 따라서 본 연구에서는 혁신특성으로 상대적 이점, 적합성, 복잡성을, 사용자특성으로는 혁신에 대한 태도, 기존제품(종이책)에 대한 태도를 변수로 도출하여 연구모형을 설정하였다. 온라인 설문조사를 실시해 각 변수들이 혁신저항에 미치는 영향을 알아보고 혁신저항과 수용의도의 관계를 검증하였다. 연구결과, 복잡성과 기존제품(종이책)에 대한 태도가 혁신저항에 영향을 미치는 결정 요인이었고, 혁신저항은 수용의도에 부정적인 영향을 미쳤다. 따라서 전자책의 구매에서부터 독서 경험 전 과정의 용이성을 높이는 데 주력해야 하며, 종이책의 사용경험과 차별화 되는 전자책 고유의 상호작용적 기능과 특성을 개발하고 부각해야 한다.

4.99톤 어선의 저항성능 개선 (Improvement of resistance performance of the 4.99 ton class fishing boat)

  • 정성재;안희춘;김인옥;박창두
    • 수산해양기술연구
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    • 제53권4호
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    • pp.446-455
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    • 2017
  • The improvement of resistance performance for the 4.99 ton class fishing boats was shown. The 4.99 ton fishing boats are the most commonly used one in the Korean coastal region. The evaluation of resistance performance was estimated by the Computational Fluid Dynamics (CFD) analysis. The CFD simulation was performed by the validation for various types of bow shapes on the hull. The optimized hull form from the simulation was selected and showed the best resistance performance. This hull type was tested on the towing tank in the National Institute of Fisheries Science (NIFS). The effective horsepower (EHP) was estimated by the resistance test on the towing tank with the bare hull condition. The drag force on the three service speed conditions was obtained for the resistance analysis to power prediction. The measured drag forces are compared with the results from the CFD simulation with one another. As results of the model tests, it was confirmed that the shape of the bow is an important factor in the resistance performance. The effective horsepower decreased about 30% in comparison with the conventional hull form. Also, the resistance performance improved the reduction of required horsepower, which especially contributed to the energy-saving for the fisheries industry. In the CFD analysis, the resistance performance improved slightly. In this case, the ratio of the residual resistance ($C_R$) in the total resistance ($C_T$) was high. Therefore, the CFD analysis was not enough to satisfy with reflection for the free surface and wave form in the CFD procedure. Both model test and CFD calculation in this study can be applied to the initial design process for the coastal fishing vessel.