Estimation of rib waveguide radiation losses

An estimative procedure given recently for approximating radiation losses from indiffused waveguides is adapted to rib waveguides and compared with a recent Huygens-type solution for bending loss. The implications for the wider application of the estimative procedure are favourable     

Social status of industries.

A sample of students (68 male, 52 female) ranked a list of 29 industries in order of social status, a second sample ranked the status of an executive in each industry, a third sample ranked the status of a laborer in each. Men and women agreed markedly in their status rankings (rho of .9) regardless of method, and the influence of occupational level stereotypes was negligible (rho of .8-.9 between rankings for pairs of stereotypes). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implementation techniques for the vehicle routing problem

Six methods for implementing the widely used Clarke-Wright algorithm for the vehicle routing problem (VRP) are presented and compared. Fifty-five large test problems are used to compare the methods. The methods involve alternative ways to access adjacency information in both low and high density problems. The results clearly establish methods of choice for VRP problems with given characteristics.     

Full vector analysis of two-dimensional angled and coated opticalwaveguide facets

We analyze the important problem of scattering from two-dimensional (2-D) optical waveguide facets, including the effects of both antireflection coatings and facet angle. The facet is allowed to be angled in both vertical and horizontal planes, necessitating a fully vectorial approach to model correctly the polarization coupling that occurs. To achieve this, the highly efficient Free Space Radiation Mode method has been extended to the general vector case, yielding novel expressions for both the reflectivity and the coupling coefficients which can be rapidly evaluated on a desktop PC for a wide variety of practical structures. Results are presented for both angled, coated and coated angled facets. Full field profiles, also available from the approach, are presented and provide useful design information and aids to understanding     

Influence of communication during the distant phase of the 1996 republican presidential primary campaign

This study examines the influence of five communication modalities on voters' perceptions of candidates during what Popkin terms 'the distant phase' of the presidential primary campaign. During the final week of the New Hampshire primary campaign, researchers surveyed 315 prospective votes in four states whose primaries followed New Hampshire's by 1, 2, 4, and 5 weeks. The results revealed that political talk radio exerted the greatest influence on voters' perceptions of Bob Dole and considerable impact on perceptions of Steve Forbes. In addition, prospective voters' conversations with other people, television news, and candidate spots (only for Forbes) exerted modest influence on voters' perceptions of Republican candidates.     

Individual characteristics and children's performance in open and traditional classroom settings.

Assessed the performance of 56 boys and 36 girls with different motivational and cognitive characteristics in 3 "open" and 3 "traditional" 4th-grade classrooms. Cluster analysis of factor scores representing child orientations, motives, and prior achievement produced 6 "types." Three-way analyses of variance investigated the effects of child type, classroom type (open vs traditional), sex of child, and various interactions on several outcome measures, including academic achievement, creativity, inquiry skill, social-educational attitudes, and teacher ratings of children's classroom behavior. Main effects appeared for each of the 3 independent variables, along with several Child * Class interactions. An approach using child types or clusters rather than abstracted dimensions may facilitate further Attribute * Treatment interaction research and applications. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavior Therapists' Professional Behaviors: A Survey Study.

Behavior therapy is often associated with an empirical-clinical methodology (Goldfried & Davison, 1976) and utilization of clinical interventions that have received research validation. Yet the extent to which self-defined behavior therapists follow these guidelines is not known. To initiate the present study, a survey was made of a random sample of 250 members of the Association for Advancement of Behavior Therapy, with a 64% return rate. The results suggest that behavior therapists do not operationalize their theoretical guidelines in many of their actual clinical cases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Model experiments illustrating fibre pull-out

Pull-out of a rigid fibre from a solid matrix has been studied in a model of a composite material using transparent media to display the fracture. Solidified gelatine solution was used to model an elastic-plastic matrix and silicone rubber used to represent a brittle elastic material. The conditions dictating both brittle and plastic failure in the model have been presented theoretically and supported by experimental observations. In addition, a novel type of failure, where bubble cracks propagated between fibre and matrix, was observed.     

Trapping levels in silicon nitride

The trapping levels in silicon nitride have been investigated using the thermally stimulated current technique. Traps at between 0.50 and 0.90eV below the conduction band of the nitride were found, as well as a distribution of traps at and near the silicon-silicon nitride interface about 0.10eV below the conduction band of the silicon.     

Latest rocket measurements of the solar constant

Three rocket flights which carried a payload of absolute radiometers to measure the solar constant with an accuracy of ±0.5 per cent have been accomplished. Several of the rocket radiometers were duplicates of those aboard the Solar Maximum Mission and Nimbus spacecrafts. The values for the solar constant obtained by the rocket sensors for the three flight dates indicate an increase between the first and latter two flights approximately equivalent to the uncertainty of the measurements. The values for the solar constant for the three flights are 1367, 1372 and 1374 Wm⁻².