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In this article, we will present a methodology to debug RGB-D SLAM systems as well as to generate testing data. We have created a model of a laboratory with an area of 250 m2 (25 x 10) with set of objects of different type. V-REP Microsoft Kinect sensor simulation model was used as a basis for robot vision system. Motion path of the sensor model has multiple loops. We have written a program in V-Rep native language Lua to record data array from the Microsoft Kinect sensor model. The array includes both RGB and Depth streams with full resolution (640 x 480) for every 10 cm of the path. The simulated path has absolute accuracy, since it is a simulation, and is represented by an array of transformation matrices (4 x 4). The length of the data array is 1000 steps or 100 m. The path simulates frequently occurring cases in SLAM, including loops. It is worth noting that the path was modeled for a mobile robot and it is represented by a 2D path parallel to the floor at a height of 40 cm. [ABSTRACT FROM AUTHOR]

The reliability and accuracy of GPS attitude determination are still the main relevant theoretical questions in this particular field of study. While the first one derives from the probabilistic nature of phase ambiguity resolution algorithms, outlier measurement detection and effectiveness of multipath reduction, the second is additionally affected by geometric properties of the GNSS antenna configuration. Being trivial in two-antenna system, the relation between GPS attitude determination accuracy and antenna spatial layout becomes much less intuitive for multi-antenna configurations, and seems to have been examined analytically in some specific cases only. For example, most of research papers in the field use Euler angles as attitude representation, which have singularity in some cases, and consider the number of antennas of not more than four. We present some further investigation in this area. [ABSTRACT FROM AUTHOR]

In this paper, the basis transformation between the Chebyshev polynomials of third kind and the Bernstein polynomials is considered and the transformation matrices are derived. [ABSTRACT FROM AUTHOR]

A new momentum-space formulation for scattering of two spin-half particles, both either identical or unidentical, is formulated. As basis states the free linear-momentum states are not expanded into the angular-momentum states, the system's spin states are described by the product of the spin states of the two particles, and the system's isospin states by the total isospin states of the two particles. We evaluate the Lippmann-Schwinger equations for the T-matrix elements in these basis states. The azimuthal behavior of the potential and of the T-matrix elements leads to a set of coupled integral equations for the T-matrix elements in two variables only, which are the magnitude of the relative momentum and the scattering angle. Some symmetry relations for the potential and the T-matrix elements reduce the number of the integral equations to be solved. A set of six spin operators to express any interaction of two spin-half particles is introduced. We show the spin-averaged differential cross section as being calculated in terms of the solution of the set of the integral equations. [ABSTRACT FROM AUTHOR]

The CQL3D bounce-averaged Fokker-Planck (FP) code [1] has been upgraded to include Finite-Orbit-Width (FOW) effects. The calculations can be done either with a fast Hybrid-FOW option or with a slower but neoclassically complete full-FOW option. The neoclassical radial transport appears naturally in the full-FOW version by averaging the local collision coefficients along guiding center orbits, with a proper transformation matrix from local (R, Z) coordinates to the midplane computational coordinates, where the FP equation is solved. In a similar way, the local quasilinear rf diffusion terms give rise to additional radial transport of orbits. The results of validation tests for the full-FOW version are presented. [ABSTRACT FROM AUTHOR]

We advocate the use of the T -matrix of the pair potential to study the properties of ultracold Fermi gases in the mean-field approximation. Our approach does not require renormalization procedures even in the limit of contact interaction, and it provides a rigorous definition of the range of the potential. We also rewrite the Bogoliubov-de Gennes equation for the pairing function as a function of the T-matrix, and use it to investigate finite-range effects on the main thermodynamic observables in a gas of 6Li atoms at unitarity, calculating the pair potential with ab initio quantum chemical methods. [ABSTRACT FROM AUTHOR]

We assess transport properties of heavy quarks in the Quark-Gluon Plasma (QGP) that show a strong non-perturbative behavior. A T-matrix approach based on a potential taken from lattice QCD hints at the presence of heavy-quark (HQ) resonant scattering with an increasing strength as the temperature, T, reaches the critical temperature, Tc ⋍ 170 MeV for deconfinement from above. The implementation of HQ resonance scattering along with a hadronization via quark coalescence under the conditions of the plasma created in heavy-ion collisions has been shown to correctly describe both the nuclear modification factor, RAA, and the elliptic flow, ν2, of single electrons at RHIC and have correctly predicted the RAA of D mesons at LHC energy. [ABSTRACT FROM AUTHOR]

In this paper, the transition matrix (abbreviated to T-matrix) formulation for scattering is adapted to the case of an obstacle immersed in a fluid half-space and in proximity to a planar interface. The formulation indicates the multiple scattering effects between the obstacle and interface, which may result in super-resonant phenomena. We investigate the application of single-channel iterative time reversal to mitigate the difficulty presented by interface reverberation by exploiting the target resonances. [ABSTRACT FROM AUTHOR]

In this paper, the radiative properties of fractal soot clusters, such as linear-chain cluster, closely packed cluster and multi-component cluster, are studied. The radiative absorption and scattering properties of clusters are analyzed by T-matrix theory in comparison with that of Mie theory. Then, the dependent scattering effects are discussed by taking the two-particle cluster and the twelve-particle cluster as examples. From the calculated results, it is found that multiple scattering in the near field and wave interference in the far field, are notable for calculation of scattering and absorption ratio of two-sphere cluster when distance between two particles is less than radius. In sequence, the corresponding interpretation for the effect of interspace on wave interference is given. Secondly, the values of radiative properties of twelve-sphere soot cluster calculated by T-matrix are distinctly greater than that of sum of single particle, which is calculated by Mie theory, in the condition of the particle volume fraction is larger than 0.1. All above mentioned is resulted from the multiple scattering and interference effect. Finally, the scattering and absorption coefficients of three typical clusters validate that the component in soot cluster have large effect on the scattering of clusters. [ABSTRACT FROM AUTHOR]

It is shown that the method of continued fractions proposed by Horácˇek and Sasakawa generates a sequence of Schwinger-like variational principles for the scattering T-matrix. Together with the variational principles, restrictions on the trial function may also be defined. Preliminary calculations show fast convergence of the method. [ABSTRACT FROM AUTHOR]

We measured the polarization-transfer coefficient Kyy′ of the fusion reaction 2H(dvector , pvector )3H at the fusion relevant energy of Ed = 58 keV at the laboratory reaction angle θ = 45°. The result is compared with theoretical predictions based on Faddeev-Yakubovsky equations, calculated with and without inclusion of the Coulomb interaction, and a prediction based on a T-matrix parametrization of all available data of this reaction at energies below 1500 keV. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Present theoretical study of liquid metal resistivity of some trivalent (La,Ce,Gd) and divalent (Eu,Yb) rare earth metals using pseudopotential has been carried out employing Ziman' s weak scattering and transition matrix (t-matrix) approaches. Our computed results of liquid metal resistivity using t-matrix approach are better than resistivity computed using Ziman's approach and are also in excellent agreement with experimental results and other theoretical findings. The present study confirms that for f-shell metals pseudopotential must be determined uniquely and t-matrix approach is more physical in comparison with Ziman's nearly free electron approach. The present pseudopotential accounts s-p-d hybridization properly. Such success encourages us to study remaining liquid state properties of these metals. [ABSTRACT FROM AUTHOR]

Manybody effects in the quasi-one-dimensional electron-hole systems are investigated under a thermal equilibrium. We figure out the Mott physics developing a self-consistent screened T-matrix approximation, by presenting a global phase diagram in terms of the exciton ionization ratio and temperature. Relevance to the optical absorption spectra is also discussed. [ABSTRACT FROM AUTHOR]

We study two dimensional electron-hole system in quasi-equilibrium. By using the self-consistent screened T matrix approximation, we present density dependence of ionization ratio. We also discuss the photoluminescence spectra, which are compared with experiment over the wide carrier density range. [ABSTRACT FROM AUTHOR]