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71.
Monfette Marie-Eve; Grimard Fran?ois; Ivers Hans; Blais Marie-Claude; Lavoie Vicky; Boisvert Jean-Marie 《Canadian Metallurgical Quarterly》2006,38(3):261
The popularity of the Fear of Negative Evaluation scale (FNE; Watson & Friend, 1969) stems from the centrality of this construct in personality, social and clinical psychology. In order to meet the needs of the Francophone researchers community, Kéroack, Boisvert, and Prévost (1987) traduced the short version of this instrument. Since social anxiety is most salient in adolescence, there is a need for normative and psychometric data for this population. This research aims at documenting the psychometric properties and norms for Francophone adolescents. Five hundred and seventy-eight participants aged from 14 to 19 years completed the French versions of the short FNE and the Social Avoidance and Distress scale. The factorial structure, the internal consistency and the convergent validity analyses confirm the traduction's quality and the questionnaire's validity. Norms are presented separately for females and males. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Francois Biquez Denis Chatrefou Jean-Marie Delcoustal Ferruccio Dianin Christian Lindner Raoul Piccoli 《华东电力》2007,35(Z1)
作为1 100 kV的UHV(特高压)输电,面临技术--生态环境的巨大挑战.变电站的UHV开关装置模块,需要的是可靠、成本/效益比好、环境友好、可维护的方案.对于这些所需的参数以及技术规范的验证,采用AIS(空气隔离变电所)技术能完全满足这些需要.介绍由瓷柱式断路器、隔离开关和NCIT(非传统互感器)所组成的UHV模块.这些装置是根据模块原理预先设计好的,其中的设备间的连接肯定允许快速安装.在变电站设备控制和检测方面,模块是预制标准化.加拿大和德国的试验站对断路器、隔离开关等独立的开关元件,在1 100 kV上做BIL、SIL和工频等绝缘试验,性能表现非常优越.因为对于特高压电压等级,IEC标准至今尚未规定,所以将根据外推法和现场数据作合理解释.瓷柱式断路器采用了最新复合绝缘体技术,在安全方面有所改进.AIS方案其他的关键技术,例如环境保护和成本,在可比的功能间,根据市场估计价值,与GIS解决方法作了比较. 相似文献
73.
Wireless LAN technologies such as IEEE 802.11a and 802.11b support high bandwidth and multi-rate data transmission to match
the channel condition (i.e., signal to noise ratio). While some wireless packet fair queuing algorithms to achieve the per-flow
throughput fairness have been proposed, they are not appropriate for guaranteeing QoS in multi-rate wireless LAN environments.
We propose a wireless packet scheduling algorithm that uses the multi-state (multi-rate) wireless channel model and performs
packet scheduling by taking into account the channel usage time of each flow. The proposed algorithm aims at per-flow protection
by providing equal channel usage time for each flow. To achieve the per-flow protection, we propose a temporally fair scheduling
algorithm called Contention-Aware Temporally fair Scheduling (CATS) which provides equal channel usage time for each flow.
Channel usage time is defined as the sum of the packet transmission time and the contention overhead time due to the CSMA/CA
mechanism. The CATS algorithm provides per-flow protection in wireless LAN environments where the channel qualities of mobile
stations are dynamic over time, and where the packet sizes are application-dependent. We also extend CATS to Decentralized-CATS
(D-CATS) to provide per-flow protection in the uplink transmission. Using an NS-2 simulation, we evaluate the fairness property
of both CATS and D-CATS in various scenarios. Simulation results show that the throughput of mobile stations with stable link
conditions is not degraded by the mobility (or link instability) of other stations or by packet size variations. D-CATS also
shows less delay and less delay jitter than FIFO. In addition, since D-CATS can coordinate the number of contending mobile
stations, the overall throughput is not degraded as the number of mobile stations increases.
This work was supported in part by the Brain Korea 21 project of Ministry of Education and in part by the National Research
Laboratory project of Ministry of Science and Technology, 2004, Korea. 相似文献
74.
Antonio Brogi Jean-Marie Jacquet Isabelle Linden 《Electronic Notes in Theoretical Computer Science》2003,68(3):284
The paper proposes a theoretical study of a coordination language embodying Linda's asynchronous communication primitive with a refined matching mechanism based on pairs composed of attribute names associated with their values. Computations in this language are described by means of an operational semantics, reporting the whole traces of executions. The non-compositionality of this intuitive operational semantics motivates the design of a compositional and fully abstract denotational semantics, which is then exploited for studying program equivalence in this setting. 相似文献
75.
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77.
Modern information systems rely more and more on combining concurrent, distributed, mobile and heterogenous components. This move from old systems, typically conceived in isolation, induces the need for new languages and software architectures. In particular, coordination languages have been proposed to cleanly separate computational aspects and communication. On the other hand, software architects face the problem of specifying and reasoning about non-functional requirements. All these issues are widely perceived as fundamental to improve software productivity, to enhance maintainability, to advocate modularity, to promote reusability, and to lead to systems more tractable and more amenable to verification and global analysis.The FOCLASA workshop was organized on August 24th 2002 as a satellite event of Concur'02 with the aim of bringing together researchers working on the foundations of component-based computing, coordination, and software architectures.This volume contains selected 12 papers presented at the workshop. They were reviewed by the program committee, consisting, besides the editors, of
- • Rocco De Nicola (University of Firenze, Italy)
- • Jos Luiz Fiadeiro (ATX Software and University of Lisbon, Portugal)
- • Roberto Gorrieri (University of Bologna, Italy)
- • Paola Inverardi (University L'Aquila, Italy)
- • Joost Kok (University of Leiden, The Netherlands)
- • Antonio Porto (New University of Lisbon, Portugal)
78.
Lagarde F Tusseau-Vuillemin MH Lessard P Héduit A Dutrop F Mouchel JM 《Water research》2005,39(19):4768-4778
This paper presents a methodology for assessing the variability of biodegradable chemical oxygen demand (COD) fractions in urban wastewaters. Thirteen raw wastewater samples from combined and separate sewers feeding the same plant were characterised, and two optimisation procedures were applied in order to evaluate the variability in biodegradable fractions and related kinetic parameters. Through an overall optimisation on all the samples, a unique kinetic parameter set was obtained with a three-substrate model including an adsorption stage. This method required powerful numerical treatment, but improved the identifiability problem compared to the usual sample-to-sample optimisation. The results showed that the fractionation of samples collected in the combined sewer was much more variable (standard deviation of 70% of the mean values) than the fractionation of the separate sewer samples, and the slowly biodegradable COD fraction was the most significant fraction (45% of the total COD on average). Because these samples were collected under various rain conditions, the standard deviations obtained here on the combined sewer biodegradable fractions could be used as a first estimation of the variability of this type of sewer system. 相似文献
79.
Multidrug transporter proteins promote the active transmembrane efflux of noxious drugs, thereby decreasing their accumulation in the intracellular medium and reducing their therapeutic efficiency. Expression of such proteins drastically reduces the efficiency of chemotherapeutic treatments against cancer and various infectious diseases. To overcome major difficulties related to the crystallization of membrane proteins, other experimental approaches have been developed to gain information on the structural changes involved in drug transport. We examine here and illustrate with a few examples how infrared and fluorescence spectroscopy can provide new insights into the structure of the membrane domains of multidrug transporters in particular. Such domains contain the drug-binding site(s) and mediate the passage of substrates across the cell membrane. 相似文献
80.
Gireaud L Grugeon S Pilard S Guenot P Tarascon JM Laruelle S 《Analytical chemistry》2006,78(11):3688-3698
In the continuing challenge to find new routes to improve the performance of commercial lithium ion batteries cycling in alkyl carbonate-based electrolyte solutions, original designs, and new electrode materials are under active worldwide investigation. Our group has focused on the electrochemical behavior of a new generation of nanocomposite electrodes showing improved capacities (up to 3 times the capacity of conventional electrode materials). However, moving down to "nanometric-scale" active materials leads to a significant increase in electrolyte degradation, compared to that taking place within commercial batteries. Postmortem electrolyte studies on experimental coin cells were conducted to understand the degradation mechanisms. Structural analysis of the organic degradation products were investigated using a combination of complementary high-resolution mass spectrometry techniques: desorption under electron impact, electrospray ionization, and gas chromatography coupled to a mass spectrometer equipped with electron impact and chemical ionization ion sources. Numerous organic degradation products such as ethylene oxide oligomers (with methyl, hydroxyl, phosphate, and methyl carbonate endings) have been characterized. In light of our findings, possible chemical or electrochemical pathways are proposed to account for their formation. A thorough knowledge of these degradation mechanisms will enable us to propose new electrolyte formulations to optimize nanocomposite-based lithium ion battery performance. 相似文献