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931.
Martini Maria G. Istepanian Robert S. H. Mazzotti Matteo Philip Nada 《Mobile Computing, IEEE Transactions on》2010,9(1):5-16
M-health is an emerging area of research and one of the key challenges in future research in this area is medical video streaming over wireless channels. Contrasting requirements of almost lossless compression and low available bandwidth have to be tackled in medical quality video streaming in ultrasound and radiology applications. On one side, compression techniques need to be conservative, in order to avoid removing perceptively important information; on the other side, error resilience and correction should be provided, with the constraint of a limited bandwidth. A quality-driven, network-aware approach for joint source and channel coding based on a controller structure specifically designed for enhanced video streaming in a robotic teleultrasonography system is presented. The designed application based on robotic teleultrasonography is described and the proposed method is simulated in a wireless environment in two different scenarios; the video quality improvement achievable through the proposed scheme in such an application is remarkable, resulting in a peak signal-to-noise ratio (PSNR) improvement of more than 4 dB in both scenarios. 相似文献
932.
Gomez Maria J.; Fassinger Ruth E.; Prosser Joann; Cooke Kathleen; Mejia Brenda; Luna Jeanette 《Canadian Metallurgical Quarterly》2001,48(3):286
This study used qualitative methodology to investigate the career development of 20 notable Latinas. The emergent theory proposed that Latina career development is influenced by sociopolitical, cultural, contextual, and personal variables. Results suggested that (a) career paths tended to be unplanned and nonlinear; (b) background variables, socioeconornic status, and educational experiences influenced the participants' sense of self and career motivation; (c) family, culture, and cultural identity werr influential; (d) relational support systems, particularly those that involved extended family, spouses, and mentors, were important; and (e) the participants' optimism, persistence, passion, and capacity for cognitive reframing helped them cope with challenges and remain true to their values, beliefs, and sense of self. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
933.
Sullivan Edith V.; Fama Rosemary; Shear Paula K.; Cahn-Weiner Deborah A.; Stein Maria; Zipursky Robert B.; Pfefferbaum Adolf 《Canadian Metallurgical Quarterly》2001,15(3):342
Motor abnormalities occur in schizophrenia (SZ) and may arise from striatal dysfunction. This study examined whether the pattern of performance on simple and complex motor abilities in SZ was similar to that of patients with Parkinson's disease (PD). Quantitative tests of speeded movement and motor and cognitive sequencing were used to assess 25 SZ, 16 PD, and 84 normal controls (NCs). Sequencing performance was also examined with motor rigidity taken into account. Compared with the NC group, the SZ and PD groups were impaired on measures of motor rigidity and motor sequencing. With rigidity accounted for, the SZ group was significantly more impaired than the PD group on motor sequencing; cognitive and motor processes contributed to the motor deficit. Cognitive sequencing performance predicted motor sequencing performance in PD but not SZ. Although both SZ and PD resulted in significant motor and cognitive sequencing deficits, the pattern and correlates of these deficits differ, suggesting that the affected neural systems underlying motor deficits in SZ are different from those involved in PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
934.
Melis Maria Rosaria; Succu Salvatora; Spano Maria Sabrina; Argiolas Antonio 《Canadian Metallurgical Quarterly》2000,114(4):849
In male rats, noncontact erections occur concomitantly with an increase in NO?- and NO?- in the paraventricular nucleus of the hypothalamus (PVN). In the present study, both responses were reduced by the blockade of PVN excitatory amino acid receptors by dizocilpine, (+)-MK-801(1 and 5 μg), but not by 6-cyano-7-nitro-quinoxaline-2,3-dione (5 μg) or (±)-2-amino-4-phosphono-butanoic acid (5 μg). Also ineffective when injected into the PVN were the dopamine antagonists SCH 23390 (5 μg), S(+)-raclopride (10 μg), and cis-flupenthixol (10 μg), and the oxytocin antagonist d(CH?)?Tyr(Me)2-Orn?-vasotocin (1 μg). However, when the last was given into the lateral ventricles, it reduced noncontact erections without modifying NO?- and NO?- increases. These results suggest that excitatory amino acid transmission increases in the PVN during noncontact erections. This may contribute to increased NO production in the PVN, and it may activate oxytocin neurons mediating this sexual response. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
935.
An electronically tunable microstrip bandpass filter using thin-film Barium-Strontium-Titanate (BST) varactors 总被引:2,自引:0,他引:2
Nath J. Ghosh D. Maria J.-P. Kingon A.I. Fathelbab W. Franzon P.D. Steer M.B. 《Microwave Theory and Techniques》2005,53(9):2707-2712
A tunable third-order combline bandpass filter using thin-film barium-strontium-titanate varactors and fabricated on a sapphire substrate is reported. Application of 0-200-V bias varied the center frequency of the filter from 2.44 to 2.88 GHz (16% tuning) while achieving a 1-dB bandwidth of 400 MHz. The insertion loss varied from 5.1 dB at zero bias to 3.3 dB at full bias, while the return loss exceeded 13 dB over the range. The third-order intercept of the filter was found to be 41 dBm. 相似文献
936.
Modern computer-controlled robots typically fail at their tasks whenever they encounter an error, no matter how minor. The physical environment of a typical assembly robot is too unstructured to benefit from conventional software approaches to reliability. We present an approach which interfaces the real-time operation of the robot with an intelligent subsystem that performs error analysis and forward recovery if a failure occurs. Our approach involves a special representation of the robot's program that efficiently tracks the robot's operation in real time and is easy to modify to include automatically generated recovery procedures. 相似文献
937.
A radial crack emanating from a circular hole in an infinite sheet under tension is considered. Depending on the crack length and location, the crack may be partially or completely open or closed. In case of closure, interfacial friction influences the solution.Stress intensity factors for inclined tension or in-plane shear are computed and compared with those obtained when closure and friction are ignored.
Résumé On considère une fissure radiale provenant d'un trou circulaire dans une tôle mince infinie sous tension. Selon la longueur et la localisation de la fissure, celle-ci peut être partiellement ou totalement ouverte ou fermeée. Dans ce dernier cas, la résolution du champ de contrainte est influencée par la friction entre faces de la fissure.On calcule les facteurs d'intensité de contrainte correspondant à une tension dont l'axe est incliné par rapport à la fissure, ou à un cisaillement dans le plan, et on compare les valeurs obtenues à celles correspondant aux cas où l'on ignore la fermeture de la fissure et la friction entre ses faces.相似文献
938.
Maria Rutkowska 《应用聚合物科学杂志》1986,31(5):1469-1482
The urethane elastomers based on 4,4′-diphenylmethane diisocyanate (MDI), oligo (ethylene adipate) (OEA) with different chain extenders, and dibromohexane or ammonium salt were synthesized. Their mechanical and thermal properties were studied by stress-strain analysis, thermomechanical methods, and differential thermal analysis. It was demonstrated that the incorporation of ionic groups in the structure of urethane elastomers due to the reaction of dibromohexane with a tertiary amine or urea NH group improves their tensile strength and thermal resistance. 相似文献
939.
Christian Nansen Lucy E.E. Barton Maria Nansen 《Journal of Stored Products Research》2007,43(4):417-424
Crack and crevice treatments are important in modern stored-beetle management, because: (1) pests are abundant in such microhabitats, (2) they potentially deliver insecticides to insect pests without contaminating food products, and (3) they can significantly reduce the need for broadcast spray applications and/or fumigations. As part of on-going research into the development of novel insecticide delivery systems to be used in processed and unprocessed food environments, we examined uptake and behavioural responses of Oryzaephilus surinamensis to an electrostatically chargeable powder, EntostatTM. Entostat is a processed plant wax and has been identified as a potential carrier for active ingredients to be delivered to cracks and crevices in food facilities. Depending upon the initial Entostat concentration in rolled oats, 0.03–0.26 μg powder was extracted from individual beetles 72 h after being transferred from treated to untreated food. SEM images showed that Entostat adhered to all body parts, including joints, between body segments, and at the insertions of body hairs. Choice experiments showed that O. surinamensis individuals were repelled, when rolled oats in cracks contained >5% Entostat. In a three-choice experiment cracks contained: (1) untreated oats, (2) oats mixed with 5% (w/w) Entostat, or (3) oats mixed with 5% (w/w) Entostat and a piece of filter paper containing a beetle attractant which was also inserted into the crack. The beetle attractant did not significantly increase the attractiveness of the crack in which it was applied, but the average powder uptake of beetles from cracks treated with the attractant was significantly higher than from the other cracks. Results presented here suggested that Entostat adhering to insects was retained over several days and that considerable amounts of Entostat were taken up even when beetles were offered a choice between treated and untreated cracks. 相似文献
940.
Review of book: Questions for Freud: The Secret History of Psychoanalysis. Cambridge, MA: Harvard University Press, 1997, xiv + 239 pp. Reviewed by Hannah S. Decker. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献