• 제목/요약/키워드: Fundamental Parameters

검색결과 954건 처리시간 0.027초

Equations to evaluate fundamental period of vibration of buildings in seismic analysis

  • Sangamnerkar, Prakash;Dubey, S.K.
    • Structural Monitoring and Maintenance
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    • 제4권4호
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    • pp.351-364
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    • 2017
  • In this study effects of various parameters like a number of bays, the stiffness of the structure along with the height of the structure was examined. The fundamental period of vibration T of the building is an important parameter for evaluation of seismic base shear. Empirical equations which are given in the Indian seismic code for the calculation of the fundamental period of a framed structure, primarily as a function of height, and do not consider the effect of number of bays and stiffness of the structure. Building periods predicted by these expressions are widely used in practice, although it has been observed that there is scope for further improvement in these equations since the height alone is inadequate to explain the period variability. The aim of this study is to find the effects of a number of bays in both the directions, the stiffness of the structure and propose a new period equation which incorporates a number of bays, plan area, stiffness along with the height of the structure.

원호형 1-3 압전 복합재 변환기의 공진 특성 (Resonance Characteristics of a 1-3 Piezoelectric Composite Transducer of Circular Arch Shape)

  • 김대승;김진오
    • 한국소음진동공학회논문집
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    • 제19권3호
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    • pp.301-312
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    • 2009
  • This paper presents a theoretical approach to calculate the resonant frequency of a thickness vibration mode in the radial direction for a 1-3 piezoelectric composite transducer of circular arch shape. For the composite transducer composed of a piezoelectric ceramic and a polymer, vibration parameters were derived according to the volume ratio of a ceramic, and a vibration characteristic equation was derived from the piezoelectric governing equations with adequate boundary conditions. The fundamental resonant frequencies were calculated numerically and verified by comparing them with those obtained from the finite element analysis and the experiment. The volume ratio and the thickness are more substantial than the curvature radius to determine the fundamental resonant characteristics, and the fundamental resonant frequency becomes higher for the larger volume ratio of the piezoelectric ceramic and for the smaller thickness.

Dynamics of a bridge beam under a stream of moving elements -Part 2 - Numerical simulations

  • Podworna, M.
    • Structural Engineering and Mechanics
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    • 제38권3호
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    • pp.301-314
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    • 2011
  • The paper constitutes the second part of the author's study. The first part (Podworna 2010) formulates four fundamental tasks in dynamics of the bridge-track-train systems. The following cyclic moving loads are considered: a concentrated forces stream (model P), an unsprung masses stream (model M), a single-mass viscoelastic oscillators stream (model $M_o$) and a double-mass viscoelastic oscillators stream (model $MM_o$). Three problems precluding to the numerical simulations have been developed, i.e., prediction of the forced resonances, the parameters of integration of equations of motion, the output results. A computer programme was written in Pascal and numerical research in the scope of the fundamental tasks was worked out. The investigations were focused on adequacy evaluation of the moving load models, P, M, $M_o$, $MM_o$, in predicting dynamic processes in railway bridges.

Exact and complete fundamental solutions for penny-shaped crack in an infinite transversely isotropic thermoporoelastic medium: mode I problem

  • LI, Xiang-Yu;Wu, J.;Chen, W.Q.;Wang, Hui-Ying;Zhou, Z.Q.
    • Structural Engineering and Mechanics
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    • 제42권3호
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    • pp.313-334
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    • 2012
  • This paper examines the problem of a penny-shaped crack in a thermoporoelastic body. On the basis of the recently developed general solutions for thermoporoelasticity, appropriate potentials are suggested and the governing equations are solved in view of the similarity to those for pure elasticity. Exact and closed form fundamental solutions are expressed in terms of elementary functions. The singularity behavior is then discussed. The present solutions are compared with those in literature and an excellent agreement is achieved. Numerical calculations are performed to show the influence of the material parameters upon the distribution of the thermoporoelastic field. Due to its ideal property, the present solution is a natural benchmark to various numerical codes and simplified analyses.

Fundamental Properties of MxP (M = Ti, V, Fe: x = 2, 3) Binary and Ternary Compounds

  • Yun, Won-Seok;Lee, Jee-Yong;Kim, In-Gee
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2012년도 임시총회 및 하계학술연구발표회
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    • pp.36-37
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    • 2012
  • In this study, the fundamental properties of $M_xP$ (M = Ti, V, Fe; x = 2, 3) binary compounds were investigated in terms of the FLAPW method within GGA. The calculated lattice parameters are well consistent with experimental values. Among considered systems, only the FM state of $Fe_xP$ compounds found to be more stable compared to the NM one. Discussion on the fundamental properties of $M_xP$ ternary compounds also will be given.

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Fundamental and plane wave solution in non-local bio-thermoelasticity diffusion theory

  • Kumar, Rajneesh;Ghangas, Suniti;Vashishth, Anil K.
    • Coupled systems mechanics
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    • 제10권1호
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    • pp.21-38
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    • 2021
  • This work is an attempt to design a dynamic model for a non local bio-thermoelastic medium with diffusion. The system of governing equations are formulated in terms of displacement vector field, chemical potential and the tissue temperature in the context of non local dual phase lag (NL DPL) theories of heat conduction and mass diffusion. Based on this considered model, we study the fundamental solution and propagation of plane harmonic waves in tissues. In order to analyze the behavior of the NL DPL model, we construct basic theorem in the terms of elementary function which determine the existence of three longitudinal and one transverse wave. The effects of various parameters on the characteristics of waves i.e., phase velocity and attenuation coefficients are elaborated by plotting various figures of physical quantities in the later part of the paper.

Investigation of Characteristics of Passive Heat Removal System Based on the Assembled Heat Transfer Tube

  • Wu, Xiangcheng;Yan, Changqi;Meng, Zhaoming;Chen, Kailun;Song, Shaochuang;Yang, Zonghao;Yu, Jie
    • Nuclear Engineering and Technology
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    • 제48권6호
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    • pp.1321-1329
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    • 2016
  • To get an insight into the operating characteristics of the passive residual heat removal system of molten salt reactors, a two-phase natural circulation test facility was constructed. The system consists of a boiling loop absorbing the heat from the drain tank, a condensing loop consuming the heat, and a steam drum. A steady-state experiment was carried out, in which the thimble temperature ranged from $450^{\circ}C$ to $700^{\circ}C$ and the system pressure was controlled at levels below 150 kPa. When reaching a steady state, the system was operated under saturated conditions. Some important parameters, including heat power, system resistance, and water level in the steam drum and water tank were investigated. The experimental results showed that the natural circulation system is feasible in removing the decay heat, even though some fluctuations may occur in the operation. The uneven temperature distribution in the water tank may be inevitable because convection occurs on the outside of the condensing tube besides boiling with decreasing the decay power. The instabilities in the natural circulation loop are sensitive to heat flux and system resistance rather than the water level in the steam drum and water tank. RELAP5 code shows reasonable results compared with experimental data.

글로우방전을 이용한 액체크로마토그라피 검출기 개발을 위한 기초특성연구 (Fundamental Studies of the Electrical Characteristics of the Glow Discharge for the Development of HPLC Detector)

  • 이현주;김효진
    • 약학회지
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    • 제39권4호
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    • pp.427-432
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    • 1995
  • The plasma oscillation has been observed in an argon pressure between a tungsten anode and cathode consisting of an aqueous conducting solution. The effects of experimental parameters on the electrical characteristics of the glow discharge have been studied. The experimental parameters include the anode-cathode distance, pressure, methanol flow rate, and cathode materials. The glow discharge with liquid cathode and solid anode showed the potential sensitive detector for HPLC

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합성음성 경보의 주관적 위급도에 관한 연구

  • 박경수;장필식
    • 대한인간공학회:학술대회논문집
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    • 대한인간공학회 1996년도 추계학술대회논문집
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    • pp.191-196
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    • 1996
  • This paper presents an experimental study of the relationship between sound parameters of synthesized voice warning and perceived(psychoacoustic) urgency. Eighteen subjects participated in two experimental sessions to evaluate and quqntify the effects of the voice parameters. Experiments showed that speech rate, fundamental frequency and voice types have clear and consistent effect on perceived urgency. The results of these experiments can be applied to the improvement of existing auditory warning systems and the design of new systems.

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레이저 용융 절단 해석 프로그램 개발 (Development of a Quality Analysis Program for Laser Fusion Cutting)

  • 이성환;민헌식
    • 한국공작기계학회논문집
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    • 제11권3호
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    • pp.72-79
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    • 2002
  • Though the laser cutting process is increasingly used in industry, a process automation and systematic database is still yet to be developed. In this study, as the fundamental step toward the construction of a reliable process expert system, a laser cutting quality monitoring/analysis system is developed based on simulations and experimental results. The relations between laser process parameters and laser cutting surface quality parameters such as kerf geometry, striation, surface roughness and dross formation are characterized and analyzed. A graphical user interface is used to visualize the results.