Set Of Dynamic Parameters Research Articles

Energy Based Determination of Identifiable Parameters of Flexible Link Robots

This paper presents an energy based method of determining a minimum set of dynamical parameters which are identifiable parameters, of flexible link robots. The use of identifiable parameters contributes to facilitate the identification process and to reduce the computational cost of the dynamic model. The energy model of these flexible structures is obtained from the finite element approach, and is shown to be linear in terms of a set of physical parameters called standard parameters. A numerical rank analysis of this model in the case of single-link and two-link plane flexible robots shows that these standard parameters are in fact identifiable parameters.

Calculation of thermal and spatial characteristics of a longitudinally blown arc

A method is proposed for calculating the thermal and spatial characteristics of the column of an electric arc in the channel of a plasmatron for a given set of averaged electrical and gas dynamical parameters. The method is based on the channel model of a longitudinally blown arc. For given discharge parameters (current intensity in the discharge, power input into the discharge, mean pump rate of the gas through the plasmatron) the method permits quite accurate determination of the temperature in the current conducting channel of the discharge arc, the radius of the channel, and distribution of the temperature fields in the nonconducting zone (heat transfer zone) as a function of the longitudinal flow coordinate z downstream. The results may be used in modeling and engineering calculations for determining the most efficient conditions for heating a gas by pumping through the channel of an arc plasmatron.

Geometry of intercalation of psoralens in DNA approached by molecular mechanics.

The results of molecular mechanical calculations on intercalation complexes of 3-carbethoxypsoralen, 5-methoxypsoralen, 8-methoxypsoralen, 7-methylpyrido[3,4-c]psoralen (MepyPs) and 7-methylpyrido[4,3-c]psoralen (2N-MePyPs) with the double stranded duodecanucleotide d(CGCGATATCGCG)2 are presented. In the energy-minimized structures, the psoralens are intercalated with their plane orthogonal to the helix axis. Stacking interactions between the furan ring of the psoralen and the adjacent bases are maximized in most derivatives studied, whereas the effect of the various substituents of the psoralen ring is to specifically push part of the molecule towards either the minor or the major groove, preventing a symmetrical intercalation (with respect to the two strands of the DNA). The relative position of the psoralen ring and of the adjacent thymine foreshadows the formation of furan-side monoadducts in 3-CPs, MePyPs and 2N-MePyPs, whereas the formation of a pyrone-side monoadduct appears as geometrically more favourable in 5-MOP and both furan- and pyrone-side monoadducts can be geometrically envisaged in 8-MOP. A good correlation therefore exists between the more or less favourable equilibrium geometries and the experimentally observed photoreactions. The present study is the first attempt to characterize the geometrical parameters as part of a complex set of geometrical, dynamical and excited state parameters governing the overall DNA-psoralen photoreaction.

Modeling speech production using dynamic gestural structures

In the present computational model of speech production, an utterance is represented as an organization of primitive linguistic units, gestures, into a larger structure, a gestural score. Each distinct gesture is linked to a particular subset of vocal tract variables (e.g., lip aperture and protrusion) and model articulators (e.g., lips and jaw), and is associated with a set of time-invariant dynamic parameters (e.g., lip aperture target, stiffness, and damping coefficients). The values of the dynamic parameters and their activation intervals are computed as part of the gestural score for a given utterance using a linguistic gestural model that includes a gesture-based dictionary of English syllables and a flexible rule interpreter for manipulating dynamic parameters and inter-gestural phasing. The gestural score serves as input to our task-dynamic model of sensorimotor coordination. In this model, the evolving configuration of the model articulators results from the gesturally and posturally specific way that driving influences generated in the tract-variable space are distributed across the associated sets of synergistic articulatory components. Coarticulation effects of various sorts are automatically produced as a function of the spatial and temporal overlap of two (or more) gestures. Significantly, explicit trajectory. planning is not required and the model functions in exactly the same way during simulations of unperturbed, mechanically perturbed, and coproduced speech gestures. [Work supported by NIH NS-13617, HD-01994, and NSF BNS 8520709.]

A self-consistent computer simulation of compound semiconductor metal-insulator-semiconductor C-V curves based on the disorder-induced gap-state model

Compound semiconductor metal-insulator-semiconductor (MIS) capacitance-voltage (C-V) curves are simulated on a computer, assuming the presence of a disorder-induced gap-state (DIGS) continuum near the interface in which bonding and antibonding states are distributed both in space and in energy around a particular charge neutrality point, EHO . A program based on Shockley–Read–Hall statistics is developed and applied to simulate a set of experimental MIS C-V curves measured on Al2 O3 /native oxide/InP MIS capacitors. By assuming a particular type of energy and spatial distribution of DIGS continuum and a suitable single set of dynamic parameters, the simulation can completely and self-consistently reproduce the experimental MIS C-V curves with complex hysteresis behavior, which varies with the bias amplitude and swing speed. The excellent agreement between theory and experiment supports the DIGS model. The danger involved in simply applying Terman’s method to determine an Nss distribution is pointed out. A quick procedure for reasonably accurate Nss measurement is suggested.

The neutral hydrogen deficiency of the cluster A262

view Abstract Citations (58) References (18) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The neutral hydrogen deficiency of the cluster A262. Giovanelli, R. ; Haynes, M. P. ; Chincarini, G. L. Abstract Seventy-two galaxies in the spiral-rich cluster A262 have been observed in the 21 cm line at Arecibo of which 67 have been observed. The H I content of individual galaxies, as compared with that of a sample of isolated galaxies, depends on the distance from the core of the cluster; while pronounced H I deficiency is observed near the central parts, normal amouns of H I are observed in the cluster periphery. With the newly available redshifts, a revised set of dynamical parameters for the cluster are given. Publication: The Astrophysical Journal Pub Date: November 1982 DOI: 10.1086/160439 Bibcode: 1982ApJ...262..442G Keywords: Galactic Clusters; Hydrogen Clouds; Interstellar Gas; Neutral Gases; Radio Sources (Astronomy); Radio Astronomy; Red Shift; Spiral Galaxies; Tables (Data); Astrophysics full text sources ADS | data products NED (73) SIMBAD (8)