Abstract Our aim is to study the backward problem, i.e. recover initial data from terminal observation, of subdiffusion with time dependent coefficients. First all, by using smoothing property solution operators and a perturbation argument freezing diffusion coefficients, we show stability estimate in Sobolev spaces, under some smallness/largeness condition on time. Moreover, case noisy data, a...

in this study, the vibration of cracked plates is investigated using the differential quadrature method and experimental modal analysis. the crack, which is assumed to be open, is modeled by the extended rotational spring. with its finite length, the crack divides the plate into six segments. then, the differential quadrature is applied to the governing differential equations of motion and the ...

Introduction: Single isocentre half-beam block (HBB) technique permits the avoidance of hot and cold spots. This technique is very useful in sparing the underlying ipsilateral lung and heart, if the left breast is treated. The major advantage of this technique is that it facilitates the complete sparing of both contralateral breast and lung. Regarding this, the present study aimed to analyse th...

Abstract—This paper deals with efficient quadrature formulas involving functions that are observed only at fixed sampling points. The approach that we develop is derived from efficient continuous quadrature formulas, such as Gauss-Legendre or Clenshaw-Curtis quadrature. We select nodes at sampling positions that are as close as possible to those of the associated classical quadrature and we upd...

Introduction Radiotherapy with small fields is used widely in newly developed techniques. Additionally, dose calculation accuracy of treatment planning systems in small fields plays a crucial role in treatment outcome. In the present study, dose calculation accuracy of two commercial treatment planning systems was evaluated against Monte Carlo method. Materials and Methods Siemens Once or linea...

We develop a fast indirect collocation method for two-sided variable-order space-fractional diffusion equation, which models, e.g., the superdiffusive transport of solute in heterogeneous porous medium. Due to impact variable fractional order, stiffness matrix loses Toeplitz structure that is common context constant-order sFDEs. Consequently, discrete Fourier transform technique or convolution ...

The wavelet transform (in the signal processing context) is a method to decompose an input signal of interest into a set of elementary waveforms, called “wavelets,” and provides a way to analyze the signal by examining the coefficients (or weights) of these wavelets. The Fourier transform also decomposes signals into elementary waveforms; however, in this case, they are global oscillations, i.e...