Multiple Quantum Flux Penetration in Superconducting Loops

The dynamics of flux entry into a superconducting loop interrupted by a thin-film Josephson junction have been studied experimentally. A computer simulation of the system yields excellent agreement with these data. It is found that a specific number of flux quanta will bubble into a loop, and that this number depends only on the relative damping which is present

Probing the Phase-Dependent Conductance and Nonequilibrium Properties of Josephson Junctions by Means of Flux Entry into Weakly Closed Loops

Numerical simulations have shown that the relative number of flux quanta which penetrate a weakly closed superconducting loop depends upon the magnitude and sign of the phase-dependent conductance. We examine the possible use of this dependence as an experimental probe of the cosy term and nonequilibrium properties of Josephson junctions

Concept talk cannot be avoided

Distinct systems for representing concepts as prototypes, exemplars, and theories are closely integrated in the mind, and the notion of concept is required as a framework for exploring this integration. Eliminating the term “concept” from our theories will hinder rather than promote scientific progress

Expansion of epicyclic gear dynamic analysis program

The multiple mesh/single stage dynamics program is a gear tooth analysis program which determines detailed geometry, dynamic loads, stresses, and surface damage factors. The program can analyze a variety of both epicyclic and single mesh systems with spur or helical gear teeth including internal, external, and buttress tooth forms. The modifications refine the options for the flexible carrier and flexible ring gear rim and adds three options: a floating Sun gear option; a natural frequency option; and a finite element compliance formulation for helical gear teeth. The option for a floating Sun incorporates two additional degrees of freedom at the Sun center. The natural frequency option evaluates the frequencies of planetary, star, or differential systems as well as the effect of additional springs at the Sun center and those due to a flexible carrier and/or ring gear rim. The helical tooth pair finite element calculated compliance is obtained from an automated element breakup of the helical teeth and then is used with the basic gear dynamic solution and stress postprocessing routines. The flexible carrier or ring gear rim option for planetary and star spur gear systems allows the output torque per carrier and ring gear rim segment to vary based on the dynamic response of the entire system, while the total output torque remains constant

Intermittent Synchronization in a Pair of Coupled Chaotic Pendula

Numerical simulations have been carried out for a pair of unidirectionally coupled identical pendula under the action of a common external ac torque. Both the master pendulum and the slave pendulum were in chaotic states. The only form of persistent locking appeared to be a computational artifact; otherwise the synchronization of slave to master was found to be intermittent

The determinants of participation in a social program: Evidence from a prototypical job training program

This paper decomposes the participation process of a prototypical program into eligibility, awareness, application, acceptance and enrollment. With this decomposition, we determine the sources of unequal participation for different groups, and demonstrate that variables often have very different effects at different stages in the participation process. Our analysis shows that personal choices substantially affect participation and that awareness of program eligibility is a major source of variation in participation.Social program participation; job training performance standards; cream skimming; job training partnership act (JTPA)

Chaos and Thermal Noise in a Josephson Junction Coupled to a Resonant Tank

Selected dynamical modes are investigated for the autonomous system formed from a dc biased Josephson junction which is resistively coupled to a resonant tank. A hysteretic zone in the current-voltage characteristic is shown to result from coexisting chaotic and periodic states. The detailed features of these states, including the geometrical structure of the attractors and their basins of attraction, as well as thermally induced transitions between them, are explored

Intermittent Synchronization of Resistively Coupled Chaotic Josephson Junctions

Numerical simulations have been used to investigate the dynamics of a pair of resistively linked Josephson junctions with ac bias. For suitable choices of parameters, the chaotic states of the two junctions become intermittently synchronized. Intervals of synchronization are interleaved between bursts of desynchronized activity. The distributions of these laminar times and their dependence on the coupling strength are determined. The role of phase winding in the definition of synchronization intervals is considered

Shade images of forested areas obtained from LANDSAT MSS data

The pixel size in the present day Remote Sensing systems is large enough to include different types of land cover. Depending upon the target area, several components may be present within the pixel. In forested areas, generally, three main components are present: tree canopy, soil (understory), and shadow. The objective is to generate a shade (shadow) image of forested areas from multispectral measurements of LANDSAT MSS (Multispectral Scanner) data by implementing a linear mixing model, where shadow is considered as one of the primary components in a pixel. The shade images are related to the observed variation in forest structure, i.e., the proportion of inferred shadow in a pixel is related to different forest ages, forest types, and tree crown cover. The Constrained Least Squares (CLS) method is used to generate shade images for forest of eucalyptus and vegetation of cerrado using LANDSAT MSS imagery over Itapeva study area in Brazil. The resulted shade images may explain the difference on ages for forest of eucalyptus and the difference on three crown cover for vegetation of cerrado

The Determinants of Participation in a Social Program: Evidence from a Prototypical Job Training Program

This paper decomposes the participation process of a prototypical program into eligibility, awareness, application, acceptance and enrollment. With this decomposition, we determine the sources of unequal participation for different groups, and demonstrate that variables often have very different effects at different stages in the participation process. Our analysis shows that personal choices substantially affect participation and that awareness of program eligibility is a major source of variation in participation.