Frontmatter

Mojzes, Paul (2017) Frontmatter, Occasional Papers on Religion in Eastern Europe: Vol. 37 : Iss. 1 , Article 1

PV Parameter Identification using Reduced I-V Data

In this paper, possibility and accuracy of using reduced I-V data in PV parameter identification are discussed. Based on the linear identification method proposed in [1], six I-V points are used instead of the whole I-V curve to identify the PV parameters. The maximum power point (MPP) is then estimated using the identified I-V and P-V characteristics. Validation is done by using different sets of six points on the I-V curve. Experiment results show that the accurate curve fitting (with low RMSE and MPE) and good estimation of MPP can be achieved

Current - voltage characteristics of break junctions of high-TcT_c superconductors

The current-voltage ($I$-$V$) characteristics of break junctions of polycrystalline La$_{1.85}$Sr$_{0.15}$CuO$_4$, Y$_{0.75}$Lu$_{0.25}$Ba$_2$Cu$_3$O$_{7-\delta}$, Bi$_{1.8}$Pb$_{0.3}$Sr$_{1.9}$Ca$_2$Cu$_3$O$_x$ and composite YBa$_2$Cu$_3$O$_{7-\delta}$ + Ag are investigated. The experimental $I$-$V$ curves exhibit the specific peculiarities of superconductor/normal-metal/superconductor junctions. The relation between an $I$-$V$ characteristic of network of weak links and $I$-$V$ dependencies of typical weak links is suggested to describe the experimental data. The $I$-$V$ curves of typical weak links are calculated by the K\"{u}mmel - Gunsenheimer - Nicolsky model considering the multiple Andreev reflections.Comment: 9 pages, 5 figures, 2 Table

Impurity in the Tomonaga-Luttinger model: a Functional Integral Approach

In this tutorial notes we review a functional bosonization approach in the Keldysh technique to one-dimensional Luttinger liquid in the presence of an impurity.Comment: 15 pages, 1 figure, Proceedings of LXXXI Les Houches School on "Nanoscopic quantum transport", Les Houches, France, June 28-July 30, 200

Thermal annealing behaviour on electrical properties of Pd/Ru Schottky contacts on n-type GaN

We have investigated the electrical properties of Pd/Ru Schottky contacts on n-GaN as a function of annealing temperature by current-voltage (I-V) and capacitance-voltage (C-V) measurements. The Schottky barrier height of the as-deposited Pd/Ru contact is found to be 0.67 eV (I-V) and 0.79 eV (C-V), respectively. Measurements showed that the Schottky barrier height increased from 0.68 eV (I-V) and 0.80 eV (C-V) to 0.80 eV (I-V) and 0.96 eV (C-V) as the annealing temperature is varied from 200 °C to 300 °C. Upon annealing at 400 °C and 500 °C, the Schottky barrier height decreased to 0.73 eV (I-V) and 0.85 eV (C-V) and 0.72 eV (I-V) and 0.84 eV (C-V), respectively. It is noted that the barrier height further decreased to 0.59 eV (I-V) and 0.72 eV (C-V) when the contact is annealed at 600 °C. The change of Schottky barrier heights and ideality factors with annealing temperature may be due to the formation of interfacial compounds at the Ru/Pd/n-GaN interface. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2788

The signature of a double quantum-dot structure in the I-V characteristics of a complex system

We demonstrate that by carefully analyzing the temperature dependent characteristics of the I-V measurements for a given complex system it is possible to determine whether it is composed of a single, double or multiple quantum-dot structure. Our approach is based on the orthodox theory for a double-dot case and is capable of simulating I-V characteristics of systems with any resistance and capacitance values and for temperatures corresponding to thermal energies larger than the dot level spacing. We compare I-V characteristics of single-dot and double-dot systems and show that for a given measured I-V curve considering the possibility of a second dot is equivalent to decreasing the fit temperature. Thus, our method allows one to gain information about the structure of an experimental system based on an I-V measurement.Comment: 12 pages 7 figure

Geometry Dependent Current-Voltage Characteristics of ZnO Nanostructures: A Combined Nonequilibrium Green’s Function and Density Functional Theory Study

Current-voltage I-V characteristics of different ZnO nanostructures were studied using a combined nonequilibrium Green’s function and density functional theory techniques with the two-probe model. It was found that I-V characteristics of ZnO nanostructures depend strongly on their geometry. For wurtzite ZnO nanowires, currents decrease with increasing lengths under the same applied voltage conditions. The I-V characteristics are similar for single-walled ZnO nanotubes and triangular cross section ZnO nanowires but they are different from I-V characteristics of hexagonal cross section ZnO nanowires. Finally, our results are discussed in the context of calculated transmission spectra and densities of states

Jet Methods in Time-Dependent Lagrangian Biomechanics

In this paper we propose the time-dependent generalization of an `ordinary' autonomous human biomechanics, in which total mechanical + biochemical energy is not conserved. We introduce a general framework for time-dependent biomechanics in terms of jet manifolds associated to the extended musculo-skeletal configuration manifold, called the configuration bundle. We start with an ordinary configuration manifold of human body motion, given as a set of its all active degrees of freedom (DOF) for a particular movement. This is a Riemannian manifold with a material metric tensor given by the total mass-inertia matrix of the human body segments. This is the base manifold for standard autonomous biomechanics. To make its time-dependent generalization, we need to extend it with a real time axis. By this extension, using techniques from fibre bundles, we defined the biomechanical configuration bundle. On the biomechanical bundle we define vector-fields, differential forms and affine connections, as well as the associated jet manifolds. Using the formalism of jet manifolds of velocities and accelerations, we develop the time-dependent Lagrangian biomechanics. Its underlying geometric evolution is given by the Ricci flow equation. Keywords: Human time-dependent biomechanics, configuration bundle, jet spaces, Ricci flowComment: 13 pages, 3 figure

Inelastic current-voltage characteristics of atomic and molecular junctions

We report first-principles calculations of the inelastic current-voltage (I-V) characteristics of a gold point contact and a molecular junction in the nonresonant regime. Discontinuities in the I-V curves appear in correspondence to the normal modes of the structures. Due to the quasi-one-dimensional nature of these systems, specific modes with large longitudinal component dominate the inelastic I-V curves. In the case of the gold point contact, our results are in good agreement with recent experimental data. For the molecular junction, we find that the inelastic I-V curves are quite sensitive to the structure of the contact between the molecule and the electrodes thus providing a powerful tool to extract the bonding geometry in molecular wires.Comment: 4 pages, 3 figure