BANDIT in NASTRAN

BANDIT has been implemented into the NASTRAN April '83 release. It is now a permanent feature in NASTRAN and will be included in all future releases for all four computing machines (IBM, CDC, UNIVAC, and VAX). Originally BANDIT operated as a preprocessor of NASTRAN. It read the NASTRAN input cards and produced a set of resequencing (SEOGP) cards that would greatly reduce the computational time required by the matrix decomposition module of NASTRAN for a large structure. In the past, many computer centers had installed BANDIT in their systems together with the NASTRAN program. The user would run the BANDIT program and NASTRAN as if they were one program (or two separated programs depending on how the two programs were actually tied together in the computer systems). In some cases, the user was required to pass the input cards and the output SEQGP cards between the two programs, and n others, the data was manipulated through the use of cataloged disc files. Although there is nothing wrong with this BANDIT-NASTRAN arrangement, there are, however, several shortcomings which are mentioned in this paper. The BANDIT in the NASTRAN April '83 release has removed all the deficiencies, and it comes in one version applicable to the four computing machines

COSMIC/NASTRAN Free-field Input

A user's guide to the COSMIC/NASTRAN free field input for the Bulk Data section of the NASTRAN program is proposed. The free field input is designed to be user friendly and the user is not forced out of the computer system due to input errors. It is easy to use, with only a few simple rules to follow. A stand alone version of the COSMIC/NASTRAN free field input is also available. The use of free field input is illustrated by a number of examples

Pre-Congestion Notification Encoding Comparison

DiffServ mechanisms have been developed to support Quality of Service (QoS). However, the level of assurance that can be provided with DiffServ without substantial over-provisioning is limited. Pre-Congestion Notification (PCN) investigates the use of per-flow admission control to provide the required service guarantees for the admitted traffic. While admission control will protect the QoS under\ud normal operating conditions, an additional flow termination mechanism is necessary in the times of heavy congestion (e.g. caused by route changes due to link or node failure).\ud Encoding and their transport are required to carry the congestion and pre-congestion information from the congestion and pre-congestion points to the decision points. This document provides a survey of\ud several encoding methods, using comparisons amongst them as a way to explain their strengths and weaknesses.\u

Recession probability indexes: a survey

Recessions ; Forecasting ; Econometric models

Spatial learning and memory in the tortoise (Geochelone carbonaria)

A single tortoise (Geochelone carbonaria) was trained in an eight-arm radial maze, with the apparatus and general procedures modeled on those used to demonstrate spatial learning in rats. The tortoise learned to perform reliably above chance, preferentially choosing baited arms, rather than returning to arms previously visited on a trial. Test sessions that examined control by olfactory cues revealed that they did not affect performance. No systematic, stereotyped response patterns were evident. In spite of differences in brain structure, the tortoise showed spatial learning abilities comparable to those observed in mammals

New Angle on the Strong CP and Chiral Symmetry Problems from a Rotating Mass Matrix

It is shown that when the mass matrix changes in orientation (rotates) in generation space for changing energy scale, then the masses of the lower generations are not given just by its eigenvalues. In particular, these masses need not be zero even when the eigenvalues are zero. In that case, the strong CP problem can be avoided by removing the unwanted $\theta$ term by a chiral transformation in no contradiction with the nonvanishing quark masses experimentally observed. Similarly, a rotating mass matrix may shed new light on the problem of chiral symmetry breaking. That the fermion mass matrix may so rotate with scale has been suggested before as a possible explanation for up-down fermion mixing and fermion mass hierarchy, giving results in good agreement with experiment.Comment: 14 page

The motion of a deformable drop in a second-order fluid

The cross-stream migration of a deformable drop in a unidirectional shear flow of a second-order fluid is considered. Expressions for the particle velocity due to the separate effects of deformation and viscoelastic rheology are obtained. The direction and magnitude of migration are calculated for the particular cases of Poiseuille flow and simple shear flow and compared with experimental data