Advances in gas permeability measurements

The Carman-Arnell equation relates the rate of flow of a fluid through a packed bed to the pressure drop across the bed. This equation is the basis for surface area determination by permeametry. It is found that the surface area measured at sub-atmospheric pressure varies with the bed porosity, so a porosity was selected where the rate of change was at a minimum. The study suggests that, at reduced pressures, the gas flow rate is a linear function of the mean pressure.     

The effect of surface configuration on grain boundary sliding

In studies of grain boundary sliding during creep, it is necessary to distinguish between the strain due to sliding in the bulk of the specimen and the strain occurring at the surface. In general, these quantities are not the same, although the difference depends on the configuration of the surface grains. Methods are suggested for estimating the internal sliding from surface measurements, and an analysis is made of detailed results published for α iron. Formerly with Department of Metallurgy, University of British Columbia, Vancouver, Canada.     

A rose by any other name . . . : Labelling bias and attitudes toward behavior modification.

Investigated the effect of presentation labels upon Ss' evaluation of behavior modification in 2 experiments with a total of 194 college students. In Exp I, 2 groups of undergraduates were shown identical videotapes of a teacher using reinforcement methods. In the 1st group the videotape was described as illustrative of "behavior modification," whereas the tape was labeled as "humanistic education" in the 2nd group. A questionnaire that required the Ss to evaluate the teacher and the lesson was then administered. Identical procedures were repeated in Exp II, which studied graduate students. For both samples, when the events on the videotape were described as illustrative of humanistic education, (a) the teacher received significantly more favorable ratings and (b) the teaching method was seen as significantly more likely to promote academic learning and emotional growth. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hop maturation and resin formation: Field trials

The resin and essential oil contents of hops (Humulus lupulus L., var., Pride of Ringwood) together with cone weight were studied over a period of 4 weeks prior to and 1 week subsequent to the estimated time of normal harvesting. The petrol ether- and methanol-soluble fractions of the hop cone showed no significant change during this period. Essential oil and α-acid contents increased gradually over the sampling period, whilst cone weight increased up to the estimated time of normal harvesting and decreased thereafter. The results indicate that, with the particular variety studied, harvesting could have been conducted over a 4-week period without significantly affecting α-acid or hop cone yield. The advantages of harvesting high-yielding hops over a 4-week period rather than planting an earlier maturing but lower-yielding variety are discussed.     

The creep behavior of discontinuously reinforced metal-matrix composites

Discontinuously reinforced metal-matrix composites (MMCs) have extensive potential for use in structural applications at elevated temperatures. However, any use at high temperatures will require a detailed understanding of the creep characteristics of the MMCs and especially the dependence of the measured creep rates on the magnitudes of the applied stress and the testing temperatures. This report examines these characteristics with special reference to the well-documented creep behavior of conventional solid-solution alloys. It is shown that creep of these MMCs is controlled by deformation in the matrix alloys and this deformation may be interpreted using a similar approach to that already developed for the creep of solid solution alloys. However, additional parameters must be considered in analyzing the creep of MMCs, including the possible presence of a threshold stress and the potential for load transfer and additional substructural strengthening. For more information, contact T.G. Langdon, University of Southern California, Departments of Aerospace and Mechanical Engineering and Materials Science, Los Angeles, CA 90089-1453, (213) 740-0491; fax (213) 740-8071; e-mail langdon@usc.edu.     

Client and therapist session satisfaction over the course of psychotherapy.

Examined the patterns of therapist and client session-by-session satisfaction (SSS) over the course of psychotherapeutic treatment as they varied by eventual outcome. The theoretical literature proposes 1 of 2 models for SSS evaluation patterns over the course of therapy for successful dyads: either linear increase over time or a curvilinear pattern. These models were examined using 23 therapist–client dyads at a university counseling center. The highly successful dyads demonstrated the curvilinear pattern for both the client and therapist evaluations and the linear pattern for the therapist, while the least successful group did not. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of sample size, estimation method, and model specification on goodness-of-fit assessments in structural equation models.

[Correction Notice: An erratum for this article was reported in Vol 75(1) of Journal of Applied Psychology (see record 2008-10492-001). An error exists in Figure 2 and the accompanying text of the article. The corrected information is included in the erratum.] The problem of assessing fit of structural equation models is reviewed, and two sampling studies are reported that examine the effects of sample size, estimation method, and model misspecification on fit indices. In the first study, the behavior of indices in a known-population confirmatory factor analysis model is considered. In the second study, the same problem in an empirical data set is examined by looking at antecedents and consequences of work motivation. The findings across the two studies suggest that (a) as might be expected, sample size is an important determinant in assessing model fit; (b) estimator-specific, as opposed to estimator-general, fit indices provide more accurate indications of model fit; and (c) the studied fit indices are differentially sensitive to model misspecification. Some recommendations for the use of structural equation model fit indices are given. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mitigation of Damages to Electric Utilities Due to High Winds

Extreme winds, hurricanes, and tornadoes produce significant damage to electrical transmission and distribution line structures. The damage produces loss of power to the affected communities for a variable length of time, depending on severity of damage. Most institutions whose operations would be life threatening in the event of power failure have emergency power. However, loss of power to both residences and businesses can have economic impact on the community in the form of temporary housing shortages and loss of business. Utility companies seem to cope with wind damage fairly well, following risk management procedures in designing for wind and in providing alternate routing for distribution lines. However, continuing research and developments are needed to keep abreast of the problem.     

CONCUR: A language for continuous, concurrent processes

Hendrix's robot modeling system presented a simulation method in which time is represented as a continuous phenomenon. This paper introduces the language CONCUR, which realizes Hendrix's concept through an extension of the LISP environment. CONCUR uses generalized procedures (scenarios) operating in a data-driven mode to implement Hendrix's events. The heart of CONCUR is a generalized pattern-matcher which permits operators within the patterns to bind variables and modify the match process. We include several detailed examples in addition to an implementation of the pattern matcher.     

The culture assimilator: An approach to cross-cultural training.

Describes the construction of self-administered programed culture training manuals, called culture assimilators. These programs provide an apparently effective method for assisting members of 1 culture to interact and adjust successfully with members of another culture. Culture assimilators have been constructed for the Arab countries, Iran, Thailand, Central America, and Greece. The steps involved in the development of these programs, and studies validating the culture assimilator programs under laboratory and field conditions are described. (21 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)