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91.
Lease Suzanne H.; Cohen Jaime E.; Dahlbeck David T. 《Canadian Metallurgical Quarterly》2007,52(4):399
Objectives: To examine whether body and sexual esteem mediated the associations between sexual satisfaction, perceived disability severity, and social perceptions of the disability and interpersonal competencies. Research Method/Design: Web-based survey with 326 adults with a range of physical disabilities. Main Outcome Measures: Perceived interpersonal competence in initiating relationships and being assertive in negative situations. Results: For men, sexual satisfaction, social perceptions of the disability, and perceived severity of the disability significantly predicted competence with relationship initiation. Sexual satisfaction and social perceptions of the disability predicted competence with negative assertion. For women, social perceptions of the disability predicted both interpersonal competencies, and sexual satisfaction predicted competence with negative assertion. Aspects of body esteem mediated the relations between the predictor variables and the interpersonal competencies. Conclusions: Findings indicate the importance of perceived attractiveness to others in mediating the negative relations between impact of the disability and interpersonal competencies. Findings also suggest important gender differences in variables predictive of interpersonal competencies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Jaime Pitarch José M Catalá-Civera Felipe L Pe?aranda-Foix Beatriz García-Ba?os 《The Journal of microwave power and electromagnetic energy》2007,41(4):46-61
Waveguide structures are very popular in the microwave power industry due to their power handling capabilities. Modal expansion of the waveguide fields and application of the circuit theory allow for the division of a complex device into several simpler sections which can be analyzed separately with the best suited method. The modal techniques can be divided into two groups--those which analyze junctions or discontinuities and those which examine propagation characteristics. In this paper, a review of modal techniques for high power applications is given. Modal expansion of the fields in the waveguides is then performed and applied to modeling of k-furcated waveguides. The modal analysis based on the Coupled Mode Method is described for the waveguides partially filled with isotropic materials. A hybrid modal analysis coupled with Finite Element Method suitable for more complex waveguide structures is also described. Computational results obtained for some real-life microwave devices are presented. Excellent agreement was found when comparing the results with those generated with a commercial FDTD simulator demonstrates the validity and reliability of the proposed method. 相似文献
93.
94.
We study pollution's ambient problems by using the optimal control theory applied to partial differential equations. We consider the problem to find the optimal way to eliminate pollution in the time, such that the concentration is close to a standard level which does not affect the ecological equilibrium when the source is pointwise. We consider a quadratic cost functional and we prove the existence and uniqueness of optimal control. We find a characterisation which makes possible the computing of optimal control. Additionally, we consider the problem moving the pointwise source. So, we define a function j(b) that associates to any point b ∈ Ω the optimal cost functional applied to the optimal control. We show that j is differentiable, provided that the controls are taken in a convenient subset of admissible functions satisfying the cone properties. We also find the point in Ω, for which the cost functional is minimum. 相似文献
95.
Fábio J.B. Brum Sandro C. Amico Ivo Vedana Jaime A. Spim 《Journal of Materials Processing Technology》2009,209(7):3166-3171
Autoclave processing is commonly used nowadays for dewaxing in the investment casting process. However, since the use of microwave is steadily growing in industrial processes and the wax interacts with the electromagnetic energy of the microwaves, the present work studies the possibility of carrying out dewaxing via microwave. The wax (mineral wax, vegetable resin, low molecular-weight polymer and anti-oxidant) used in this work was prepared by melting in an oven equipped with a mineral oil bath. The chemical and structural stability of the wax were monitored throughout 12 simulated dewaxing cycles, via various analyses, namely, volumetric expansion, hardness, Fourier transform infrared spectroscopy, ultraviolet–visible spectrophotometry, differential scanning calorimetry and viscosity. The results showed that microwave dewaxing is viable, significantly decreasing the incorporation of dirt and water, which is inevitable in the autoclave dewaxing process. 相似文献
96.
Jaime González‐Buesa Ana Ferrer‐Mairal Rosa Oria María L. Salvador 《Packaging Technology and Science》2013,26(7):413-421
Most experimental systems for measuring the permeability of microperforated polymeric films are static, mainly because in dynamic systems the small differences in pressure on both sides of the perforation may result in serious errors in the measurements. The O2 and CO2 transmission rate through microperforations of different sizes (from 40 × 30 to 350 × 110 µm) were determined in a static and in a dynamic system. In the latter case, rather than the diffusive flow, the hydrodynamic flow generated by the difference in pressure was measured (between 5 and 90 mbar). This was determined by applying Bernouilli's theorem and an experimental equation potentially relating the area of the microperforation with the transmission rate. A comparison of the transmission rates obtained in both cases gives coefficients of determination close to one (>0.993). This means that measuring the hydrodynamic flow can be considered as an alternative for the quantification of the diffusive flow through a microperforation. This is a simple and quick methodology that does not require expensive equipment. Furthermore, this feature enables commercial leak detection equipment to be used to quantify diffusive transmission rates through microperforations. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
97.
G. Pacheco-Malagn Norma. A. Sanchez-Flores J. Saniger-Blesa L. Baos P. Prez-Romo Jaime S. Valente Mara de L. Guzman-Castillo F. Hernndez-Beltrn Jos J. Fripiat 《Microporous and mesoporous materials》2007,100(1-3):70-76
This contribution deals with the synthesis of a silicon-rich ZSM-5 obtained from an amorphous organo-alumino-silicic gel. The gel was formed by reacting a mechanical mixture of RHA (rice hull ash), silica’s source, and of natural clinoptilolite, source of alumina, with glycerol during 2 h at 200 °C. After a maturation period of one day at 60 °C, the reaction product was hydrolyzed by a tetra-propyl-ammonium (TPA) solution and then aged for two days at 135 °C in a stainless steel autoclave. After washing and drying, the X-ray pattern showed a well crystallized ZSM-5. The textural analysis of the slowly calcined solid at 500 °C for 4 h, and the SEM micrographies evidence that the zeolite was supported on mesoporous silica. The proportion of both components depends on the tunable hydrolysis conditions. 相似文献
98.
Open DRM and the Future of Media 总被引:1,自引:0,他引:1
This article offers an analysis of the various methods for implementing interoperable digital rights management platforms. 相似文献
99.
José Cheel Cristina Theoduloz Jaime A. Rodríguez Peter D.S. Caligari Guillermo Schmeda-Hirschmann 《Food chemistry》2007,102(1):36-44
The total phenolic, flavonoid and anthocyanin content of achenes (true fruit) and thalamus (receptacle) from the native South American Fragaria chiloensis ssp. chiloensis (f. patagonica and f. chiloensis), Fragaria vesca and Fragaria x ananassa cv. Chandler was determined by spectrophotometric means. Highest phenolic content was found in F. vesca while lowest content was measured for white strawberry (F. chiloensis ssp. chiloensis, f. chiloensis). The total anthocyanin and total flavonoid contents in the samples investigated was lower for the white strawberry and higher in F. x ananassa cv. Chandler. Total flavonoid content showed a better correlation than total anthocyanins with the free radical scavenging effect of the extracts measured by means of the DPPH discoloration assay. In the superoxide anion assay all the acetone extracts of strawberries showed similar activity. The data presented in this study demonstrate that the amount of phenolic compounds differ significantly between species and subspecies and determine the free radical scavenging activity of fruits. On a w/w basis, higher total phenolics including flavonoids was found in achenes. The highest total anthocyanin content was found in the achenes of F. chiloensis and F. vesca, while F. ananassa presented higher antocyanin content in thalamus. The main anthocyanin in thalamus of F. ananassa (95%) were pelargonidin derivatives which were also present in F. chiloensis ssp. chiloensis f. patagonica (62.6%) but were not detected in F. vesca and F. chiloensis ssp. chiloensis f. chiloensis. In F. vesca and F. chiloensis ssp. chiloensis f. chiloensis only cyanidin derivatives were found both in thalamus and achenes. 相似文献
100.
De La Cruz-Blas C.A. Lopez-Martin A. Carlosena A. Jaime Ramirez-Angulo 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2005,52(7):376-379
A current-mode CMOS RMS-DC converter is presented. The basic building blocks are based on a novel approach to design current-mode computational cells. In such an approach, the large-signal V-I characteristic of class-AB transconductors is conveniently exploited leading to a very regular and compact implementation. A proper biasing scheme in such transconductors allows operation with supply voltage as low as V/sub GS/+2V/sub DSsat/. Measurement results from a practical prototype are presented in order to demonstrate the technique proposed here. 相似文献