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51.
Three studies examined the hypothesis that the relation between self-rated happy affect and overall smiling during dyadic interactions is moderated by one's relative power. In all 3 studies, interpersonal power was experimentally manipulated, and smiling and self-reported happy affect were measured during and after the interaction, respectively. Happy affect was positively correlated with overall smiling for both low-power and high-power participants. Moreover, the correlations for both low- and high-power participants were comparable to those found when power roles were not unequal or made salient, based on analysis of the present studies as well as comparison with the previously published literature. Happy affect and overall smiling had a positive relation that was not moderated by interpersonal power. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Jiangxuan Song Mingjiong Zhou Ran Yi Terrence Xu Mikhail L. Gordin Duihai Tang Zhaoxin Yu Michael Regula Donghai Wang 《Advanced functional materials》2014,24(37):5904-5910
Silicon has attracted ever‐increasing attention as a high‐capacity anode material in Li‐ion batteries owing to its extremely high theoretical capacity. However, practical application of silicon anodes is seriously hindered by its fast capacity fading as a result of huge volume changes during the charge/discharge process. Here, an interpenetrated gel polymer binder for high‐performance silicon anodes is created through in‐situ crosslinking of water‐soluble poly(acrylic acid) (PAA) and polyvinyl alcohol (PVA) precursors. This gel polymer binder with deformable polymer network and strong adhesion on silicon particles can effectively accommodate the large volume change of silicon anodes upon lithiation/delithiation, leading to an excellent cycling stability and high Coulombic efficiency even at high current densities. Moreover, high areal capacity of ~4.3 mAh/cm2 is achieved based on the silicon anode using the gel PAA–PVA polymer binder with a high mass loading. In view of simplicity in using the water soluble gel polymer binder, it is believed that this novel binder has a great potential to be used for high capacity silicon anodes in next generation Li‐ion batteries, as well as for other electrode materials with large volume change during cycling. 相似文献
53.
Stephen S. Nonnenmann Mohammad A. Islam Brian R. Beatty Eric M. Gallo Terrence McGuckin Jonathan E. Spanier 《Advanced functional materials》2012,22(23):4957-4961
The synthesis of cylindrical silicon‐core and ferroelectric oxide perovskite‐shell nanowires and their response characteristics as individual three‐terminal nanoscale electronic devices is reported. The co‐axial nanowire geometry facilitates large ferroelectric field‐effect modulation (>104) of nanowire conductivity following sequential application and removal of an applied dc field. Source‐drain current–voltage traces collected during sweeps of ferroelectric gate potential and switching of the component of shell outward and inward polarization provide direct evidence of ferroelectric coupling on nanowire channel conductance. Despite a very small (1:20) ferroelectric‐to‐semiconductor channel thickness ratio, an unexpectedly strong electrostatic coupling of ferroelectric polarization to channel conductance is observed because of the co‐axial gate geometry and curvature‐induced strain enhancement of ferroelectric polarization. 相似文献
54.
Supercritical Carbon Dioxide (SC CO2) is used as a reaction/processing medium in the fabrication of fiber‐reinforced composite materials. SC CO2 allows resin (reactive monomer), to penetrate inside the fibers themselves, partitioning into the amorphous regions of the fiber. The crystal structure then templates polymerization of matrix within the fiber. This process produces a composite that exhibits ultralong‐range order from the nanoscale reinforcement of crystals to the macroscale fiber reinforcement of matrix. In addition, SC CO2 lowers resin viscosity and aids in wetting out Nylon 6,6 fiber reinforcement in a process similar to reaction injection molding (RIM) or resin transfer molding (RTM). This article will discuss the fabrication technique in detail, including process parameters and the structure of resulting composites and morphology of modified fibers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1600–1607, 2003 相似文献
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Donato G Bartlett MS Hager JC Ekman P Sejnowski TJ 《IEEE transactions on pattern analysis and machine intelligence》1999,21(10):974
The Facial Action Coding System (FACS) [23] is an objective method for quantifying facial movement in terms of component actions. This system is widely used in behavioral investigations of emotion, cognitive processes, and social interaction. The coding is presently performed by highly trained human experts. This paper explores and compares techniques for automatically recognizing facial actions in sequences of images. These techniques include analysis of facial motion through estimation of optical flow; holistic spatial analysis, such as principal component analysis, independent component analysis, local feature analysis, and linear discriminant analysis; and methods based on the outputs of local filters, such as Gabor wavelet representations and local principal components. Performance of these systems is compared to naive and expert human subjects. Best performances were obtained using the Gabor wavelet representation and the independent component representation, both of which achieved 96 percent accuracy for classifying 12 facial actions of the upper and lower face. The results provide converging evidence for the importance of using local filters, high spatial frequencies, and statistical independence for classifying facial actions. 相似文献
59.
Terrence E. Murphy Kwok-Leung Tsui Janet K. Allen 《Research in Engineering Design》2005,15(4):201-215
Problems in engineering design often involve determining design variable settings to optimize individual product performance for multiple criteria, which are often in conflict. We review mathematically rigorous techniques from the statistical literature for finding a vector x of design variable settings, which produces an optimal compromise solution among a group of prioritized response variables. The best compromise solution is typically gained by optimizing an objective function, which incorporates the prioritized demands of multiple responses. Since most multi-response objective functions are constructed by combining the functions used to optimize univariate responses, a review of the prominent univariate approaches is presented first. A multivariate approach from the engineering literature called the compromise decision support problem (cDSP) is also reviewed. Finally, a table comparing the relative merits of the different multivariate approaches summarizes the article in a concise and user-friendly fashion. 相似文献
60.
The quality of lipid from steelhead trout viscera, a byproduct of steelhead trout industry, was evaluated and compared with that of the muscle. Steelhead trout viscera had a higher lipid content than muscle and the visceral oil differed from muscle oil in its lipid class composition. Neutral lipids, mainly triacylglycerols (TAG), comprised the major lipid class in both muscle and visceral lipid. However, as expected, muscle contained a remarkably higher level of phospholipids (PL) than viscera, and the ratio of total neutral lipids to polar lipids was lower in muscle than in viscera. Visceral and muscle lipid had similar fatty acid compositions, with the concentration of muscle polyunsaturated fatty acids (PUFA) slightly higher than that of visceral PUFA. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were the major n-3 PUFA present in both muscle and visceral lipid; docosapentaenoic acid (DPA) was present at about 1.61–1.76%. With respect to minor components, muscle lipid had higher α-tocopherol and total carotenoids contents than visceral lipid. Oxidative stability of visceral and muscle lipid, as determined by conjugated dienes (CD) and thiobarbituric acid reactive substances (TBARS), showed that visceral lipid was more stable against oxidation than muscle lipid, probably due to their different lipid profiles. Besides, carotenoids, which were present more abundantly in muscle, might have acted as prooxidants and therefore, decreased the oxidative stability of muscle lipid. These results suggest that steelhead trout viscera may serve as a good source of lipid and could be utilized for production of omega-3 oils. 相似文献