• Advances in concrete construction
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• 제15권5호
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• pp.349-358
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• 2023

Aim of this work is investigating effect of thickness-stretching formulation on the quasi three-dimensional analysis of micro plate based on a thickness-stretched and shear deformable model through principle of virtual work and micro-scale dependent constitutive relations. Governing differential equations are derived in terms of five unknown functions and the analytical solution is derived using Navier's technique. To explore effect of thickness stretching model on the static results, a comparison between the results with and without thickness stretching effect is presented.

• Steel and Composite Structures
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• 제50권5호
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• pp.489-497
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• 2024

A temperature-dependent generalized thermoelasticity is constructed in the context of a new consideration of the multi-phase-lags model. The theory is then adopted to study wave propagation in anisotropic homogenous generalized magneto-thermoelastic medium under the influence of gravity whose boundary is subjected to thermal and mechanical loading. The basic equations of the problem are solved by using normal mode analysis. The numerical quantities of physical interest are obtained and depicted graphically. Some comparisons of the results are shown in figures to study the effects of the magnetic field, temperature discrepancy, and the gravity field.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.272-275
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• 2007

This paper is concerned with modified integration algorithm on the strain-space for rate and temperature dependent elasto-plastic constitutive relations in order to obtain more accurate results in numerical implementation. The proposed algorithm is integrated analytically using integration by part and chain rule and then is applied to the 2-stage Lobatto IIIA with second-order accuracy. It has advantage that is able to consider the convective stress rates on the yield surface of the strain-space. Also this paper is carried out the iteration procedure using the Newton-Raphson method to enforce consistency at the end of the step. And the performance of the proposed algorithm for rate and temperature dependent constitutive relation is illustrated by means of analysis of adiabatic shear bands.

• Journal of applied mathematics & informatics
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• 제17권1_2_3호
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• pp.495-508
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• 2005

We investigated both classical and quantum properties of a damped harmonic oscillator with a time-variable elastic coefficient using invariant operator method. We acquired the energy eigenvalues, uncertainties and probability densities for several types of wave packet. The probability density corresponding to the displaced minimum wave packet expressed in terms of the time-dependent Gaussian function. The displaced minimum wave packet not only be attenuated but also oscillates about x = 0. We confirmed that there exist correspondence between quantum and classical behaviors for the time-dependent damped harmonic oscillator.

• Management Science and Financial Engineering
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• 제4권2호
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• pp.1-13
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• 1998

The Shortest Path Problem in Time-dependent Networks, where the travel time of each link depends on the time interval, is not realistic since the model and its solution violate the Non-passing Property (NPP:often referred to as FIFO) of real phenomena. Furthermore, solving the problem needs much more computational and memory complexity than the general shortest path problem. A new model for Time-dependent Networks where the flow speeds of each link depend on time interval, is suggested. The model is more realistic since its solution maintains the NPP. Solving the problem needs just a little more computational complexity, and the same memory complexity, as the general shortest path problem. A solution algorithm modified from Dijkstra's label setting algorithm is presented. We extend this model to the problem of Minimum Expected Time Path in Time-dependent Stochastic Networks where flow speeds of each link change statistically on each time interval. A solution method using the Kth-shortest Path algorithm is presented.

• 대한산업공학회지
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• 제33권1호
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• pp.70-75
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• 2007

This paper discusses condition based preventive replacement for deteriorating systems. The system continuouslydeteriorates in time and fails at any deterioration level which is always monitored, It is replaced at failure or atsome deteriorated level preventively before failure. The deterioration process is represented by a Weibulldistribution with a time-linear scale parameter. The cost rate function is formed considering replacement costand opportunity loss cost and deterioration dependent failure distribution, If the system has an increasingdeterioration dependent failure rate, the optimal deterioration level for preventive replacement can be determinedfrom minimizing the cost rate. An illustrative example is given for a Weibull deterioration dependent failuredistribution.

• Structural Engineering and Mechanics
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• 제18권3호
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• pp.363-376
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• 2004

The present study provides a relatively simple and accurate analytical model for the prediction of time-dependent stresses and curvatures of cracked R.C. sections under working loads. A more simplified solution is also provided. The proposed models are demonstrated by considering a numerical example and conducting a parametric study on the effects of relevant R.C. design parameters. In contrary to tension reinforcement, the compression reinforcement is found to contribute significantly in reducing tensile stresses in tension steel and in reducing the total section curvatures. The good accuracy of the proposed approximate solution opens a new vision towards a simple yet accurate model for the prediction of time-dependent effects in R.C. structures.

• 제어로봇시스템학회논문지
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• 제10권7호
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• pp.618-624
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• 2004

This paper presents a delay dependent fuzzy H_\infty$ filter design method for delayed fuzzy dynamic systems. Using delay-dependent Lyapunov function, the global exponential stability and H_\infty$ performance problem are discussed. A sufficient condition for the existence of fuzzy filter is presented in terms of linear matrix inequalities(LMIs). The filter design utilize the concept of parallel distributed compensation. And the filter gains can also be directly obtained from the LMI solutions. A simulation example is given to illustrate the design procedures and performance of the proposed methods.

• 충청수학회지
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• 제31권3호
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• pp.287-308
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• 2018

This paper deals with blow-up phenomena for an initial boundary value problem of a quasilinear parabolic equation with time-dependent coefficient in a bounded star-shaped region under nonlinear boundary flux. Using the auxiliary function method and differential inequality technique, we establish some conditions on time-dependent coefficient and nonlinear functions for which the solution u(x, t) exists globally or blows up at some finite time $t^*$. Moreover, some upper and lower bounds for $t^*$ are derived in higher dimensional spaces. Some examples are presented to illustrate applications of our results.

• 대한전자공학회논문지
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• 제10권6호
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• pp.25-44
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• 1973

원인과 결과간의 위상과 work사이의 관계를 correlation function의 견지에서 검토하였고 continuous signal에 포함되어 있는 redundancy를 지적하여 sampling취급의 근거를 auto correlation면에서 보였다. 두 신호사이의 Correlation의 시간변동을 보여줄 수 있는 Time Dependent Correlation Function을 정의하여 PLL회로에서 그 유편성을 보였다. 끝으로 다상포낙선검파법에 의한 특성의 개선을 T.D.Correlation Furction에 의한 Correlation Analysis를 통하려 입증하였다.