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71.
Studied 47 short-term psychotherapy cases (aged 18–33 yrs) from a college counseling center that followed the evolution of the focus from the patient's presenting problem, through the formulation of the focus during the consultation, to the stated focus at termination. Findings suggest that the presenting complaint was not the same as the consultation or the termination focus and that the consultation focus was not the same as the termination focus. The longer the time-limited therapy progressed, the more likely it was that the focus was revised between the time of the initial consultation and termination. Clinical examples of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Presents an overview of the barriers associated with the effective delivery of school psychological services in rural areas, including transportation and accessibility, social-cultural, and professional problems. Based on a review of the relevant literature in special education and community, clinical, and school psychology, strategies for overcoming each of these barriers are offered. Some of the advantages of practicing school psychology in a rural setting are discussed. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
A new class of printed circuit radiator consisting of a microstrip dipole electromagnetically coupled to a microstrip feed line is described. Several configurations which differ in bandwidth, efficiency, and construction simplicity are presented. A geometry which has been found to be optimum for many applications is noted. Radiation characteristics of both isolated elements and arrays of elements are examined. Experimental and theoretical results are presented. 相似文献
74.
An antenna element consisting of a slot plus two parasitically excited wires has been found to exhibit many properties useful in array applications. The introduction of the wires provides a means of controlling both theE - andH -plane element radiation patterns. Specifically, the principal plane radiation patterns can be equalized and the directivity increased. If desired, the element pattern can closely approximate acos theta pattern in both planes. A 14-dB reduction in interelement mutual coupling is also achievable with this source as compared to a slot alone. A comparison of the characteristics of a four-quadrant 60-slot monopulse array with and without the wire elements indicates a 0.6-dB increase in gain and a significant reduction in back radiation for the former. 相似文献
75.
A finite element formulation is presented for the equations governing the steady thermohydrodynamic behaviour of liquid lubricated bearings. This formulation permits application of the iterative solution scheme to bearings of arbitrary geometry. A generalized Reynolds equation resulting from the combination of the mass and momentum conservation equations is cast into variational form and used to derive general finite element equations. The method of weighted residuals with Galerkin's criterion is used to generate finite element matrix equations for the thermal energy equation. In addition to the finite element formulation, a discussion of appropriate finite difference techniques is also given for problems without complex geometry. As an example, the formulations are applied to obtain numerical solutions for a three-dimensional sector thrust bearing operating in the thermohydrodynamic regime. Pressure, velocity and temperature distributions are give, and the thermohydrodynamic solutions are compared with the results of classical isothermal theory. 相似文献
76.
Hoyt Michael A.; Nemeroff Carol J.; Huebner David M. 《Canadian Metallurgical Quarterly》2006,25(4):455
This study investigated the relationship between suppressing thoughts about HIV risk and several outcomes related to HIV risk, including sexual risk behavior and HIV prevention service use, in men who have sex with men (MSM). Synthesizing the ironic processing theory (D. M. Wegner, 1994) with a cognitive escape paradigm (D. J. McKiman, D. G. Ostrow, & B. Hope, 1996), it was hypothesized that thought suppression might increase risk by leading MSM to "escape" from sexual safety norms and engage in risky sex behaviors and, via a paradoxical process, increase future use of community prevention services. Results from a sample of MSM (N = 709) indicated that thought suppression was positively related to concurrent sexual risk behavior and to future use of prevention services. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Highly Textured BaTiO3 via Templated Grain Growth and Resulting Polarization Reversal Dynamics 下载免费PDF全文
William Meier Kelsey Elizabeth Meyer Dorina F. Sava Gallis Mia Angelica Blea‐Kirby Joshua Roth Daniel Felman Tim Breuer Gary J. Dension Fred J. Zutavern Wayne Huebner Geoff L. Brennecka 《Journal of the American Ceramic Society》2016,99(3):922-929
Samples of bulk textured polycrystalline BaTiO3 ceramics were fabricated using a templated grain growth (TGG) approach in order to investigate effects of polycrystallinity and texture related to ferroelectric domain reversal under high‐power drive conditions. Barium titanate platelets were formed via two‐step topochemical conversion of bismuth titanate platelets grown via molten salt synthesis, then aligned via tape casting within a matrix of fine BaTiO3 powder. The coarse‐grained parts showed a high degree of crystallographic texture after sintering. Combined with ceramics of similar density and polycrystallinity, but random orientation and commercial single‐crystal specimens, this sample set enabled direct isolation of crystallographic texture and polycrystallinity as the primary variables for high‐power polarization reversal studies. These studies have also demonstrated a link between grain size and polarization reversal time that strongly suggests that grain boundaries serve effectively as nucleation sites during the ferroelectric switching process. 相似文献
78.
Composite PTCR thermistors utilizing conducting borides,silicides, and carbide powders 总被引:1,自引:0,他引:1
Ceramic-polymer composite thermistors using conducting boride, silicide, and carbide powders that include TiB2, ZrB2, NbB2, NbSi2, WSi2, MoSi2, and TiC have been fabricated. Percolation and subsequent PTCR effects were observed for all the powders in both semi-crystalline (polyethylene) and amorphous (epoxy) polymer matrix materials, however, as found for carbon black and metal fillers, both niobate powders did not exhibit a PTCR effect in the amorphous polymer. Results indicate that percolation and PTCR behaviour are related to the powder characteristics (size/distribution), composite microstructure and ceramic-polymer interface.Composite thermistors with room temperature resistivities as low as 1 cm and a nine-order of magnitude change () at 1 kHz (12 at d.c.) were achieved. 相似文献
79.
Gesche M. Huebner Megan McMichael David Shipworth Michelle Shipworth Mathieu Durand-Daubin Alex J. Summerfield 《Building Research & Information》2015,43(2):185-196
The most commonly used family of models in representing the UK building stock, BREDEM (the Building Research Establishment Domestic Energy Models), assume that all homes exhibit the same heating pattern and hence can be expected to have similar temperature profiles over the course of a day. The presented research shows that homes differ significantly in their respective temperature profile over the course of the day. A cluster analysis performed on temperature data from 275 living rooms in English homes over three winter months resulted in four different clusters of temperature profiles. The clusters differ significantly in their shape, as revealed by visual inspection, and supported by significant differences in minimum and maximum temperatures and temperature variability across the day. About 40% of homes showed a bimodal temperature pattern as assumed under BREDEM. However, the remaining 60% showed very different profiles. These findings challenge the assumption that one standard pattern fits all homes. Different temperature demand profiles have important implications for future peak power demands, particularly if domestic space heating is switched to electricity. It is also helpful for relating occupant demographics to appropriate forms of fabric retrofit. 相似文献
80.
Hufnagel M Koch S Kropec A Huebner J 《International journal of food microbiology》2003,88(2-3):263-267
Enterococci are commonly used in foods and food additives. A number of putative virulence factors are usually evaluated to assure that the strains used are not harmful. We propose an additional test to assess the safety of these bacteria by testing the susceptibility to opsonophagocytic killing. One probiotic Enterococcus faecalis strain was compared to a collection of 27 clinical isolates and our results indicate that 89% of the clinical strains were less susceptible to killing mediated by normal rabbit sera. Opsonophagocytic killing is the best in vitro surrogate for a protective immune response against bacteria, and the susceptibility of bacteria against normal rabbit sera indicates that these strains may not be able to survive in the bloodstream of the host. Further studies comparing a larger collection of pathogenic strains with commensal isolates are necessary to confirm these findings. 相似文献