Search results for "integral"
showing 10 items of 902 documents
A Wiener Path Integral Technique for Non-Stationary Response Determination of Nonlinear Oscillators with Fractional Derivative Elements
2014
In this paper a novel approximate analytical technique for determining the non-stationary response probability density function (PDF) of randomly excited linear and nonlinear oscillators with fractional derivative elements is developed. Specifically, the concept of the Wiener path integral in conjunction with a variational formulation is utilized to derive an approximate closed form solution for the system response non-stationary PDF. Notably, the determination of the non-stationary response PDF is accomplished without the need to advance the solution in short time steps as it is required by the existing alternative numerical path integral solution schemes. In this manner, the analytical Wi…
Path-integral Monte Carlo study of crystalline Lennard-Jones systems.
1995
The capability of the path-integral Monte Carlo (PIMC) method to describe thermodynamic and structural properties of solids at low temperatures is studied in detail, considering the noble-gas crystals as examples. In order to reduce the systematic limitations due to finite Trotter number and finite particle number we propose a combined Trotter and finite-size scaling. As a special application of the PIMC method we investigate $^{40}\mathrm{Ar}$ at constant volume and in the harmonic approximation. Furthermore, isotope effects in the lattice constant of $^{20}\mathrm{Ne}$ and $^{22}\mathrm{Ne}$ are computed at zero pressure. The obtained results are compared with classical Monte Carlo result…
Path integral Monte Carlo study of the internal quantum state dynamics of a generic model fluid
1996
We study the quantum dynamics of a generic model fluid with internal quantum states and classical translational degrees of freedom in two spatial dimensions. The path integral Monte Carlo data for the imaginary time correlation functions are presented and analyzed by the maximum entropy method. A comparison of the frequency distribution with those of a mean field approximation and virial expansion shows good agreement at high and low densities, respectively. \textcopyright{} 1996 The American Physical Society.
Multifacet structure of observed reconstructed integral images.
2005
Three-dimensional images generated by an integral imaging system suffer from degradations in the form of grid of multiple facets. This multifacet structure breaks the continuity of the observed image and therefore reduces its visual quality. We perform an analysis of this effect and present the guidelines in the design of lenslet imaging parameters for optimization of viewing conditions with respect to the multifacet degradation. We consider the optimization of the system in terms of field of view, observer position and pupil function, lenslet parameters, and type of reconstruction. Numerical tests are presented to verify the theoretical analysis.
Roadmap on 3D integral imaging: Sensing, processing, and display
2020
This Roadmap article on three-dimensional integral imaging provides an overview of some of the research activities in the field of integral imaging. The article discusses various aspects of the field including sensing of 3D scenes, processing of captured information, and 3D display and visualization of information. The paper consists of a series of 15 sections from the experts presenting various aspects of the field on sensing, processing, displays, augmented reality, microscopy, object recognition, and other applications. Each section represents the vision of its author to describe the progress, potential, vision, and challenging issues in this field.
Lightfield recording and reconstruction by integral imaging
2011
Integral imaging is a rising 3D imaging technique that can be considered the incoherent version of holography. In integral imaging the multiperspective information of 3D scenes is stored in a 2D picture. Such picture is nothing but a sampling version of the lightfield emitted by the 3D scene. The recorded lightfield can be used for many purposes. One is the display of 3D color scenes to audiences or much more than one person. Other is the 3D display, with full parallax, in personal monitors, like the screen of a Smartphone, a tablet, or the monitor used by a surgeon in an endoscopic operation. Other important types of applications are connected with the topographic reconstruction, slice by …
Plant virus cell-to-cell movement is not dependent on the transmembrane disposition of its movement protein
2009
ABSTRACT The cell-to-cell transport of plant viruses depends on one or more virus-encoded movement proteins (MPs). Some MPs are integral membrane proteins that interact with the membrane of the endoplasmic reticulum, but a detailed understanding of the interaction between MPs and biological membranes has been lacking. The cell-to-cell movement of the Prunus necrotic ringspot virus (PNRSV) is facilitated by a single MP of the 30K superfamily. Here, using a myriad of biochemical and biophysical approaches, we show that the PNRSV MP contains only one hydrophobic region (HR) that interacts with the membrane interface, as opposed to being a transmembrane protein. We also show that a proline resi…
Captura y procesado de imágenes de alta resolución mediante sistemas de microscopía integral
2017
El desarrollo de nuevas tecnologías de adquisición de imágenes 3D ha experimentado un avance significativo en los últimos años. Una de las técnicas capaces de preservar la información espacio-angular de objetos extensos es la conocida como Imagen Integral. Desde su invención a principios del siglo XX, los sistemas de captura de imagen integral han sido objeto de numerosos estudios, siendo sus aplicaciones muy diversas. Una de las aplicaciones que más interés ha despertado entre los investigadores es la posibilidad de llevar a cabo una reconstrucción en profundidad del objeto, a partir de la información 3D registrada tras una única captura. En la última década, ha tenido lugar un creciente i…
Mutual inductance of thick coils for arbitrary relative orientation and position
2017
An exact solution method has been developed recently which gives the mutual inductance of two thin cylindrical coils in terms of line integrals of a new kind of vector potential, induced by the primary coil, around the two circular edges of the secondary coil. This paper describes the extension of this method to thick coils, by wrapping two radial integrations around these line integrals. Results are presented for two pairs of conventional coils and a combination of a superconducting coil and a Bitter coil. Excellent agreement with existing results for non coaxial coils was obtained. The trade-off between accuracy and computing time is also examined.
A new result on impulsive differential equations involving non-absolutely convergent integrals
2009
AbstractIn this paper we obtain, as an application of a Darbo-type theorem, global solutions for differential equations with impulse effects, under the assumption that the function on the right-hand side is integrable in the Henstock sense. We thus generalize several previously given results in literature, for ordinary or impulsive equations.