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1.
The aim of this study was to investigate the role of English as Foreign Language (EFL) learners’ metacognitive listening strategies awareness and podcast-use readiness in using podcasting technology for learning English as a foreign language. One hundred and forty-one EFL students completed Metacognitive Awareness Listening Questionnaire (MALQ) that assessed their awareness and perceived use of listening strategies in five components including planning-evaluation, directed attention, person knowledge, mental translation, and problem solving. They also completed a questionnaire that assessed their readiness to use podcasting in terms of familiarity, attitude, and experience. Information on participants’ frequency of podcast use for learning English, frequency of the internet use, and digital device ownership was also obtained. The result of the analysis revealed that podcasting use was significantly related to metacognitive listening strategies awareness in general and its entire components except mental translation strategies while the strongest correlation was found with problem solving strategies (r = .49, p < 0.01). Podcasting use was also found to be significantly related to perceived podcast-use readiness and internet use hours. Further, multiple regressions showed that perceived podcast-use readiness, problem solving, and person knowledge -in order of power prediction- were good predictors of podcasting use for learning English as a foreign language. 相似文献
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Evaluating the Effect of Essential Oil Extraction Method from Satureja macrosiphonia on Its Biological Activities: Ohmic‐ and Microwave‐Assisted Hydrodistillation 下载免费PDF全文
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J. Saydi M. Karimi M. Mazhdi J. Seidi F. Mazhdi 《Journal of Materials Engineering and Performance》2014,23(10):3489-3496
Nanocrystalline ZnO and Mn (1 wt.%)-doped ZnO particles have been synthesized via reverse micelle method. The structural, particulate, and optical properties of the synthesized nanoparticles have been studied by XRD, TEM, UV-Vis, and PL spectroscopy. The obtained data indicate the synthesis of the pure nanoparticles structure with wurtzite structure, average particle size of 18-21 nm, and high optical quality. Gas sensing properties of the nanocrystalline ZnO and Mn-doped ZnO particles toward gasoline and ethanol vapors have been investigated at different temperatures and concentrations. The results show that the optimum working temperature of the gas sensors based on ZnO and Mn-doped ZnO particles are about 633 and 620 K toward ethanol vapor and about 560 and 608 K toward gasoline vapor, respectively. Based on the results, although Mn impurities reduce the sensitivity of the ZnO gas sensor, they cause sensor to saturate at much higher gas concentration. 相似文献
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Laurent Franck Grard Maral 《International Journal of Satellite Communications and Networking》2002,20(6):455-475
This paper presents and evaluates different routing schemes in a constellation of non‐geostationary satellites. Routing decisions may or may not take into account the state of the network. While taking into account the network state is likely to bring an improvement in both the network utilization and the quality of service, it also makes the routing architecture more complex. This paper proposes to evaluate the advantages and disadvantages of these different design approaches for routing. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Poethi Boedhihartono Grard Maral 《International Journal of Satellite Communications and Networking》2003,21(2):163-182
Handover is one of the key subjects in maintaining the quality of service offered by non‐geostationary constellation systems. As the satellite coverage moves according to the satellite motion, the continuity of a call must be maintained from one satellite to another. In case the handover fails, the call is dropped, resulting in a quality of service degradation. This paper proposes several handover procedures that guarantee a successful handover in non‐geostationary satellite constellations requiring mutual visibility. Reservations at next satellite must be done in advance in order to avoid call drops. Several handover performance metrics (such as call blocking probability, call dropping probability and handover rate) are presented for each procedure as a function of traffic load variation. Comparisons of handover performance metrics between these procedures are presented as well. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
7.
Werner M. Delucchi C. Vogel H.-J. Maral G. De Ridder J.-J. 《Selected Areas in Communications, IEEE Journal on》1997,15(1):69-82
An asynchronous transfer mode (ATM)-based concept for the routing of information in a low Earth orbit/medium Earth orbit (LEO/MEO) satellite system including intersatellite links (ISLs) is proposed. Specific emphasis is laid on the design of an ATM-based routing scheme for the ISL part of the system. The approach is to prepare a virtual topology by means of virtual path connections (VPCs) connecting all pairs of end nodes in the ISL subnetwork for a complete period in advance, similar to implementing a set of (time dependent) routing tables. The search for available end-to-end routes within the ISL network is based on a modified Dijkstra (1959) shortest path algorithm (M-DSPA) capable of coping with the time-variant topology. With respect to the deterministic time variance of the considered ISL topologies, an analysis of optimization aspects for the selection of a path at call setup time is presented. The performance of the path search in combination with a specific optimization procedure is-by means of extensive simulations-evaluated for example LEO and MEO ISL topologies, respectively 相似文献
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The resolution of systems of stiff differential equations is required in the transient analysis of a large electronic network simulation. Resultant stability problems and the methods used in solving first order stiff nonlinear differential equations are reviewed. An improved algorithm is presented using BDF formulas given by Brayton et al. IEEE Vol 60 (1972) pp 98–108 and has been implemented in the IMAG electronic circuit simulation program. Reducing computer time has been achieved by controlling the number of Newton iterations, the number of integration steps, and the number of Jacobian matrix evaluations without producing additional errors or instability phenomena. Experimental results are shown. 相似文献
10.
Cecilia Berlin Lars-Ola Bligrd Maral Babapour Chafi Siw Eriksson 《人机工程学与制造业中的人性因素》2022,32(1):151-170
In any work system design intervention—for example, a physical workplace re-design, a work process change, or an equipment upgrade—it is often emphasized how important it is to involve stakeholders in the process of analysis and design, to gain their perspectives as input to the development, and ensure their future acceptance of the solution. While the users of an artifact or workplace are most often regarded as being the most important stakeholders in a design intervention, in a work-system context there may be additional influential stakeholders who influence and negotiate the design intervention's outcomes, resource allocation, requirements, and implementation. Literature shows that it is uncommon for empirical ergonomics and human factors (EHF) research to apply and report the use of any structured stakeholder identification method at all, leading to ad-hoc selections of whom to consider important. Conversely, other research fields offer a plethora of stakeholder identification and analysis methods, few of which seem to have been adopted in the EHF context. This article presents the development of a structured method for identification, classification, and qualitative analysis of stakeholders in EHF-related work system design intervention. It describes the method's EHF-related theoretical underpinnings, lessons learned from four use cases, and the incremental development of the method that has resulted in the current method procedure and visualization aids. The method, called Change Agent Infrastructure (abbreviated CHAI), has a mainly macroergonomic purpose, set on increasing the understanding of sociotechnical interactions that create the conditions for work system design intervention, and facilitating participative efforts. 相似文献