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81.
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
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83.
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
84.
85.
Wilches D Rovira J Jaime I Palacios C Lurueña-Martínez MA Vivar-Quintana AM Revilla I 《Meat science》2011,88(3):415-423
The aim was to evaluate the effect of maternal rearing system on the chemical composition and odour profile of meat from suckling lamb. Twenty-four single male suckling lambs raised exclusively on maternal milk came from two rearing systems (extensive and intensive), and from Castellana and Churra breeds. The fatty acid composition of lamb meat from both breeds was affected by the rearing system, and Churra lamb reared under the extensive system had noticeable changes in odour attributes as detected by panellists and an electronic nose. Using partial least squares-discriminant analysis, the electronic nose was able to discriminate accurately between samples of Churra and Castellana meat according to their production system. However, it was not able to correctly classify meat samples from the extensive and intensive systems when both breeds were analysed together. The results suggest a significant effect of the rearing system and breed on suckling lamb meat quality traits. 相似文献
86.
A novel method for dyeing human hair fibres using coloured silica nanoparticles of 206 nm has been developed. Diffusion of coloured silica nanoparticles into hair fibres has been investigated; silica nanoparticles do not penetrate at all, or do so only sparingly, into the structure of Caucasian virgin hair. However, coloured silica nanoparticles diffused readily into bleached hair fibres. Scanning electron microscopy showed that coloured silica nanoparticles were present mainly in the outer regions of the hair structure (the inner layers of the cuticle and the outer region of the cortex). It was found that the silica nanoparticles were physically entrapped in the hair fibres and results showed a good shampoo fastness to washing. 相似文献
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88.
Antonio J. Lopez‐Martin Lucia Acosta Coro Garcia‐Alberdi Ramon G. Carvajal Jaime Ramirez‐Angulo 《International Journal of Circuit Theory and Applications》2012,40(11):1143-1163
A class AB version of the conventional super source follower (SSF) is described. The circuit greatly increases slew rate (SR) and current efficiency, maintaining the low distortion and low output resistance of the SSF. Class AB operation is achieved without extra power dissipation or supply requirements, and without bandwidth or noise degradation. The circuit can advantageously replace the SSF in a wide variety of analog systems, opening a new research line in analog design. To illustrate the widespread application of this cell, a class AB differential unity‐gain buffer, a class AB differential current mirror and two class AB differential transconductors are designed, fabricated in a 0.5µm CMOS technology and tested. Measurement results using a dual supply of ±1.65V show that the proposed class AB version of the SSF improves SR by a factor 21.5 and increases bandwidth by 10%, keeping noise level, input range, power consumption, and supply requirements unaltered. The fabricated class AB current mirror features a THD at 100 kHz of ? 62dB for signal currents 20 times larger than the bias current. The fabricated transconductors feature an IM3 at 1 MHz of ? 56.6dB for output currents more than 13 times larger than the bias currents. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
89.
Jose M. Algueta Antonio J. Lopez‐Martin Jaime Ramirez‐Angulo Ramon G. Carvajal 《International Journal of Circuit Theory and Applications》2014,42(8):831-841
A technique to improve the input and output range of CMOS transconductors with resistive current division for continuous tuning is presented. Using it, a tunable transconductor is proposed which features high linearity over a wide input range and simplicity. Measurement results of the transconductor, fabricated in a 0.5 µm CMOS process, show an IM3 of ?66 dB for a ±1.65 V supply and two input tones centered at 1 MHz of 1 Vpp each, and only 0.7 mW of power consumption. This represents an improvement of 13 dB versus the same transconductor using conventional current division. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
90.
Luis Fortino Cisneros‐Sinencio Alejandro Diaz‐Sanchez Jaime Ramirez‐Angulo Hector Vazquez‐Leal 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(6):692-694
Multiple‐input floating‐gate transistor (FGMOS) circuit designers face a serious problem along the design process: the lack of a realistic simulation model. For this reason, a solution that properly predicts the initial voltage at the floating gates is presented in this paper. In order to assess the performance of the proposal, a comparison is made against a test circuit fabricated in a 0.5‐µm On‐Semiconductor CMOS process. Based on this comparison, the proposed model is shown to be a fundamental tool in the design of FGMOS circuits. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献