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1.
2.
Upper bounds on the bit error probability are applied to evaluate the error performance of coded systems over non-interleaved and partially interleaved Rician fading mobile channels. The correlation between successive received symbols is exploited to bound the error performance. The bound allows useful evaluation of coding gains on realistic communication systems without going into lengthy computer simulations. By further defining the maximum energy degradation factors, compact upper bounds are expressed in a similar way as on the fully interleaved or memoryless channels. The maximum energy degradation factors are computed for a wide variety of mobile channel conditions. These factors give an interesting evaluation of the fading conditions and may be used to design coded communication systems on mobile channels. Furthermore, independent space or frequency diversity may be taken into account in these bounds and it is shown that the energy degradation due to correlation is independent of this added independent diversity 相似文献
3.
Opioid receptor antagonists have been studied in the management of self-injurious behavior (SIB) in developmentally disabled individuals. The authors present a case of a severely retarded, autistic man whose SIB increased dramatically during a trial of naltrexone. A paradoxical increase in SIB, attributed to the extinction burst phenomenon during the initial period of nonreward, is known to occur during treatment with naloxone, a short-acting parenteral opioid antagonist. It has only once been reported during treatment with naltrexone, a long-acting orally administered agent. Opioid analgesic effects and learning theory can explain both increases and decreases in SIB after opioid blockade. 相似文献
4.
B van Hout D Gagnon E Souêtre S Ried C Remy G Baker P Genton H Vespignani P McNulty 《Canadian Metallurgical Quarterly》1997,38(11):1221-1226
PURPOSE: The relationship between seizure frequency and both health care costs and quality of life (QOL) was investigated in a retrospective, cross-sectional, multicenter study in France, Germany, and the United Kingdom. METHODS: Three hundred outpatients with stable partial epilepsy were approximately evenly distributed among five seizure-frequency groups, ranging from seizure-free in the last 3 months (group 1) to daily seizures (group 5). Economic data, obtained through patient interviews and record abstraction, comprised direct medical costs, direct nonmedical costs, and indirect costs for the preceding 3 months. Total societal costs in the three countries were pooled and converted to United States dollar equivalents. QOL was assessed through a self-administered questionnaire, the Functional Status Questionnaire (FSQ). RESULTS: Mean total costs increased from $780 in group 1 to $2,171 in group 5 (p = 0.0001), with significant increases in each cost category as seizure frequency increased. Greater seizure frequency also significantly (p = 0.0270) correlated with lower employment rates, which ranged from 57% in group 1 to 30% in group 5. QOL declined as seizure frequency increased. Particularly affected were basic and intermediate activities of daily living (ADL), mental health, social activity, and feeling about health. CONCLUSIONS: The study results show that higher seizure frequencies are associated with higher direct and indirect costs and with reduced QOL for patients with epilepsy. 相似文献
5.
A simple phase-characterization method for spatial light modulators is proposed. The low-cost method permits high-precision measurement and provides data for the setting of the spatial-light-modulator operating point in the phase-modulation mode. The dynamic phase response is used to perform efficient kinoform recording. In order to record the kinoform, we modify the global iterative coding to compute phase holograms. Finally, modified phase-phase correlation is introduced. The phase-phase correlator permits sharper correlation peaks, better energy transmission, and higher discrimination than an amplitude-phase correlation. Optical experimental results are presented. 相似文献
6.
G. A. Gagnon K. C. O’Leary C. J. Volk C. Chauret L. Stover R. C. Andrews 《Canadian Metallurgical Quarterly》2004,130(11):1269-1279
Drinking water utilities may be required to change disinfectant to improve water quality and meet more stringent disinfection regulations. This research was conducted to assess and compares chlorine dioxide to free chlorine and chloramines on bacterial water quality monitored within model distribution systems (i.e., annular reactors). Following colonization with nondisinfected water, annular reactors containing either polycarbonate or cast iron coupons were treated with free chlorine, chlorine dioxide or chloramines. Two disinfectant doses (low/high) were tested for each disinfectant. Under specific environmental conditions, bacterial inactivation varied as a function of the disinfectant type and dose, sample type (bulk water versus biofilm bacteria) and coupon material. The ranking by efficiency was as follows: chlorine dioxide > chlorine > chloramines. On preformed biofilms of 106–107?cfu/cm2, the continuous application of a disinfectant led to a log removal of heterotrophic bacteria concentrations for suspended and biofilm bacteria ranging from 1.1 to 4.0, and from 0.2 to 2.5, respectively. Doubling the amount of disinfectant doses led to an additional log inactivation of 1–2.5 of heterotrophic bacteria levels. This study demonstrates that bacterial inactivation in distribution systems is governed by various inter-related parameters. The data indicate that chlorine dioxide represents a viable alternative for secondary disinfection in distribution systems. 相似文献
7.
Nicholas Gagnon 《电信科学》2008,24(4):124-125
在无源光网络(PON)上激活服务后,电话、高速互联网和视频信号从中心局(CO)的光线路终端(OLT)发送到用户不同位置的光网络终端(ONT).这种情况下,如果有一个ONT出现故障,并且不能与OLT同步重启,PON的这一支路会进入非激活状态,并将暂停此支路相关用户的服务,这时必须找技术人员来进行故障诊断并重新启动服务.而一旦出现在非激活位置,技术人员必须测量光功率级别,以确定其是否足以使ONT与OLT同步. 相似文献
8.
Moussadak Ettayebi Richard Gagnon 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(3):319-339
Résumé: Dans cet article, l'utilisation de réseaux conceptuels pour repérer les conceptions d'élèves se rapportant à des phénomènes thermiques est explorée. Des informations sur ces conceptions, obtenues par le biais de 16 entrevues semi‐structurées individuelles, sont rapprochées d'une approximation de la structure cognitive des élèves, obtenue par le biais d'une épreuve de rendement à correction critériée traditionnelle, analysée et pondérée à la lumière d'une structure conceptuelle de référence des phénomènes thermiques. Cette seconde méthode est appelée ? méthode des réseaux conceptuels pondérés ? (RCP). Un degré de concordance significatif entre la méthode des entrevues semi‐structurées et la méthode RCP résulte de ce rapprochement, laissant entrevoir pour les enseignantes et les enseignants la possibilité de repérer plus facilement qu'au moyen d'entrevues les conceptions de leurs élèves, dans la pratique ordinaire de leur enseignement. 相似文献
9.
Soybean Allergens Affecting North American Patients Identified by 2D Gels and Mass Spectrometry 总被引:1,自引:0,他引:1
Christine Gagnon Vaino Poysa Elroy R. Cober Stephen Gleddie 《Food Analytical Methods》2010,3(4):363-374
In this study, we compared the immunoglobulin E immunological reactions of 23 soy-allergic, nine soy-sensitive, and four non-allergic
human sera to soybean proteins separated by 1D and 2D gel electrophoresis and screened by Western blot. This method led to
novel allergen identification in soybean proteins by tandem mass spectrometry analysis of reactive proteins. Soybean is one
of the eight most significant foods which provoke allergic reactions among North Americans. Previous studies have identified
several putative allergens present in soybean seeds; however, many of these reports did not employ mass spectrometry to conclusively
identify the allergenic proteins. Reviews have suggested that soybean seeds may contain between 10 and 20 different proteins
responsible for provoking allergic reactions among sensitive patients. We report, in this study of North American patients,
a total of 19 potentially allergenic proteins including ten identified by mass spectrometry and five novel allergens. We have
also made extensive use of soybean lines lacking various subunits of the major seed storage proteins, glycinin and β-conglycinin.
By using these knockout lines in Western blots with patient serum, it was conclusively demonstrated that some patients react
predominantly to only a few proteins, while most react to four to six proteins. The findings herein describe the main allergic
proteins present in soybean seeds, the relative significance of these allergens among North Americans, and some genetic lines
of soybean lacking individual allergens. 相似文献
10.
Cocontraction changes in muscular fatigue at different levels of isometric contraction 总被引:1,自引:0,他引:1
Denis Gagnon A. Bertrand Arsenault Gilmen Smyth Fran ois Kemp 《International Journal of Industrial Ergonomics》1992,9(4):343-348
Ten normal subjects participated in a study designed to contrast results obtained in pre- and post-fatigue states. The measures contrasted were the IEMG ratios of agonist/antagonist pairs of muscles. The experimental task was an 8 s ramp isometric elbow flexion ranging from 0 to 100% of a maximal voluntary contraction (MVC). IEMG ratios were obtained at levels of 20, 40, 60 and 80% MVC. Records from the following muscles were obtained with surface electrodes: biceps brachii (BB), brachioradialis (BR), triceps brachii (TB) and anconeus (SU). The torque at the elbow joint was measured by a Cybex II dynamometer. Fatigue was induced using a 60% MVC of elbow flexion maintained during 5 minutes. The data were collected on-line at a sampling rate of 1 kHz. The results indicated that the IEMG ratios (BB/TB and BR/SU) presented a tendency, across subjects, toward a decrease at the levels of 40%, 60% and 80% MVC at the post- relative to the pre-fatigue state. The BB/BR ratios remained stable. These changes in the post-fatigue ratios disclose a tendency toward a saturation of the agonist occurring concomitantly with an increased level of contraction of the antagonists. 相似文献