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81.
Bragg gratings used as input-output couplers in polymeric waveguides have been demonstrated at infrared wavelengths. These Bragg grating couplers were holographically formed volume phase gratings with a near-45 degrees fringe slant angle embedded directly into a waveguide layer. A photopolymer was used for both producing a planar waveguide and constructing the embedded Bragg grating coupler. A coupling efficiency of 23% for input and 5% for output has been achieved at 850 nm. The output-coupling beam profiles are also discussed. 相似文献
82.
Roisman Glenn I.; Holland Ashley; Fortuna Keren; Fraley R. Chris; Clausell Eric; Clarke Alexis 《Canadian Metallurgical Quarterly》2007,92(4):678
Although 10 studies have been published on the empirical overlap of the Adult Attachment Interview (AAI) and measures of self-reported attachment style, results in this literature have been inconsistently interpreted in narrative reviews. This report was designed as a rapprochement of the AAI and attachment style literatures and includes 3 studies. Study 1 (combined N = 961) is a meta-analytic review showing that by J. Cohen's (1992) criteria (mean r = .09), the association between AAI security and attachment style dimensions is trivial to small. Study 2 (N = 160) confirms meta-analytic results with state-of-the-art assessments of attachment security and also examines attachment dimensions in relation to the Big 5 personality traits. Finally, Study 3 is an investigation of 50 engaged couples that shows that developmental and social psychological measures of attachment security predict somewhat distinct--though theoretically anticipated--aspects of functioning in adult relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
Don Ashley 《电子产品世界》2007,(10):68-68,70
引言 作为白炽灯的替换品,LED灯近年来才开始推出市场,但却面临着诸多难题.由于将LED功率驱动电路装入标准灯壳具有难度,因此早期的一些LED灯并没有内部滤波器,也就谈不上符合EMC标准. 相似文献
84.
J. Alison Bryant Ashley Sanders-Jackson Amber M. K. Smallwood 《Journal of Computer-Mediated Communication》2006,11(2):577-592
Building on previous research in computer-mediated communication, social and communication networks, and adolescent development, this article raises three issues regarding adolescent use of socially interactive technologies (SITs) and their relationship to offline social networks: 1) whether adolescents are creating more, but weaker ties using SITs, 2) to what extent adolescent SIT-facilitated networks overlap with friendship networks, and 3) whether SIT relationships are important for adolescents who have fewer offline peer ties. In order to investigate these questions, network data collection and analysis were integrated with more traditional questionnaire methodology and statistical analysis. The results show that the adolescents in the study were not creating more ties using SITs, nor were they necessarily creating weaker SIT-based ties; that there was little overlap between SIT-facilitated and offline social networks; and that socially isolated adolescents were less likely than other adolescents to use SITs. 相似文献
85.
Watson M.D. Ashley P.R. Abushagur M.A.G. 《Quantum Electronics, IEEE Journal of》2004,40(11):1555-1561
A charge density and current density model of a waveguide system has been developed to explore the effects of electric field electrode poling. An optical waveguide is modeled during poling by considering the dielectric charge distribution, polarization charge distribution, and conduction charge generated by the poling field. The charge distributions are the source of poling current densities. The model shows that boundary charge current density and polarization current density are the major source of currents measured during poling and thermally stimulated discharge measurements. Charge distributions provide insight into the poling mechanisms and are directly related to E/sub A/ and /spl alpha//sub r/. Initial comparisons with experimental data show excellent correlation to the model results. 相似文献
86.
Abbie E Smith Ashley A Walter Jennifer L Graef Kristina L Kendall Jordan R Moon Christopher M Lockwood David H Fukuda Travis W Beck Joel T Cramer Jeffrey R Stout 《Journal of the International Society of Sports Nutrition》2009,6(1):5
Background
Intermittent bouts of high-intensity exercise result in diminished stores of energy substrates, followed by an accumulation of metabolites, promoting chronic physiological adaptations. In addition, β-alanine has been accepted has an effective physiological hydrogen ion (H+) buffer. Concurrent high-intensity interval training (HIIT) and β-alanine supplementation may result in greater adaptations than HIIT alone. The purpose of the current study was to evaluate the effects of combining β-alanine supplementation with high-intensity interval training (HIIT) on endurance performance and aerobic metabolism in recreationally active college-aged men. 相似文献87.
Ashley T. Dean A.B. Elliott C.T. McConville C.F. Whitehouse C.R. 《Electronics letters》1988,24(20):1270-1272
Molecular-beam epitaxy has been used for the first time to fabricate np junctions in InSb grown onto p -type InSb (100) substrates. Diodes formed by the epitaxial growth of a silicon-doped layer on undoped homoepitaxial material exhibited a bulk generation-recombination-limited R 0A value of 105 Ω cm2 and D λpk * of 3×1012 cm Hz1/2 W-1 at liquid nitrogen temperature 相似文献
88.
H King S Ashley D Brathwaite J Decayette DJ Wooten 《Canadian Metallurgical Quarterly》1993,77(1):84-88
Ejaculated spermatozoa from four different boars were used to evaluate the acrosome reaction during in vitro fertilization with homologous ovulated oocytes. The acrosome reaction was assessed according to a peroxidase-labeling peanut agglutinin method and a triple-stain technique. An increase in the proportion of living sperm with reacted acrosomes was observed after preincubation and 2 hr of coincubation (P < 0.05). The percentage of true acrosome-reacted sperm remained reasonably constant throughout coincubation. In vitro penetration rates of oocytes varied among boars, but no relationship was found between fertilization rates of oocytes and maximum percentages of acrosome reacted living sperm. 相似文献
89.
This article outlines the development of a digital three-term industrial controller from the initial marketing requirement to the final product. The major functions of the instrument are performed by a 3872 masked microprocessor. An EAROM is used to provide nonvolatile storage for operator-entered parameters and to store instrument characterisation data. A 6809 based programming/calibration station and a portable programmer for in-field programming are also described. 相似文献
90.
Ashley J.J. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1988,34(3):389-399
The author gives an upper bound on the necessary length of a sliding-block decoder window for finite-state codes from arbitrary n -ary data into any constrained system Σ with capacity at least log(n ) presented by a graph G with memory m and anticipation a . Specifically, it is shown that the ACH code construction algorithm can be used to construct a code with a sliding-block decoder at rate t :t and with window length m +a +2t , where t is upper-bounded by a linear function of the number of states of G. It is demonstrated that this is the best one can do in the sense that any general upper bound on the decoder window length for finite-state codes into systems Σ with finite memory must grow at least linearly with the number of states of the graph G presenting Σ 相似文献