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1.
Anna Potocki Mathilde Chailleux Manuel Gimenes Jean Pylouster 《Journal of Computer Assisted Learning》2021,37(5):1324-1335
Many studies have demonstrated the crucial role of vocabulary in predicting reading performance in general. More recent work has indicated that one particular facet of vocabulary (its depth) is more closely related to language comprehension, especially inferential comprehension. On this basis, we developed a training application to specifically improve vocabulary depth. The objective of this study was to test the effectiveness of a mobile application designed to improve vocabulary depth. The effectiveness of this training was examined on 3rd and 4th grade children's vocabulary (breadth and depth), decoding and comprehension performances. A randomized waiting-list control paradigm was used in which an experimental group first received the intervention during the first 4 weeks (between pretest and post-test1), thereafter, a waiting control group received the training for the next 4 weeks (between postest1 and posttest2). Results showed that the developed application led to significant improvements in terms of vocabulary depth performance, as well as a significant transfer effect to reading comprehension. However, we did not observe such a beneficial effect on either vocabulary breadth or written word identification. These results are discussed in terms of the links between vocabulary depth and comprehension, and the opportunities the app presents for remedying language comprehension deficits in children. 相似文献
2.
Andrea Bedon Jean Paul Viricelle Mathilde Rieu Simone Mascotto Antonella Glisenti 《International Journal of Hydrogen Energy》2021,46(27):14735-14747
In this contribution brownmillerite-based nanocomposite cathode for Single-Chamber Solid Oxide Fuel Cells is developed. These cells can be very attractive especially for small and cheap devices because of the absence of seals. The efficiency of SC-SOFCs is strictly connected to the selectivity of anode and cathode, the bottleneck for this technology. The development of a cathode inert in fuel oxidation is particularly challenging. Our strategy is to start from a catalytically un-active support (CFA = Ca2FeAl0.95Mg0.05O5) and induce the formation of iron oxide based nanoparticles, expected to activate oxygen. Symmetric (CFA + FeOx/CGO/CFA + FeOx) and complete cells (CFA + FeOx/CGO/Ni-CGO) are studied in air and methane/oxygen 2:1 mixture. The Area Specific Resistance of CFA + FeOx is less than 1/3 that of CFA. The high selectivity allows to reach an efficiency of 25%; power still needs to be increased but we demonstrated the possibility to develop selective low cost electrodes. The effect of air, methane/oxygen exposure and the heat treatments were carefully investigated. 相似文献
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Given a collection of parameterized multi-robot controllers associated with individual behaviors designed for particular
tasks, this paper considers the problem of how to sequence and instantiate the behaviors for the purpose of completing a
more complex, overarching mission. In addition, uncertainties about the environment or even the mission specifications
may require the robots to learn, in a cooperative manner, how best to sequence the behaviors. In this paper, we approach this
problem by using reinforcement learning to approximate the solution to the computationally intractable sequencing problem,
combined with an online gradient descent approach to selecting the individual behavior parameters, while the transitions
among behaviors are triggered automatically when the behaviors have reached a desired performance level relative to a task
performance cost. To illustrate the effectiveness of the proposed method, it is implemented on a team of differential-drive
robots for solving two different missions, namely, convoy protection and object manipulation. 相似文献
7.
Timo Baur Rebecca Breu Tibor Kálmán Tobias Lindinger Anne Milbert Gevorg Poghosyan Helmut Reiser Mathilde Romberg 《Journal of Grid Computing》2009,7(3):319-333
In many Grid infrastructures different kinds of information services are in use, which utilize different incompatible data structures and interfaces to encode and provide their data. Homogeneous monitoring of these infrastructures with the monitoring data being accessible everywhere independently of the middleware which provided it, is the basis for a consistent status reporting on the Grids’ resources and services. Thus, interoperability or interoperation between the different information services in a heterogeneous Grid infrastructure is required. Monitoring data must contain the identity of the affected Virtual Organization (VO) so that it can be related to the resources and services the VO has allocated to enable VO-specific information provision. This paper describes a distributed architecture for an interoperable information service, which combines data unification and categorization with policies for VO membership, VO resource management and data transformations. This service builds the basis for an integrated and interoperating monitoring of Grids, which provide their data to more than one VO and utilize heterogeneous information services. 相似文献
8.
Sabeha Yala Mahfoud Boustta Olivier Gallet Mathilde Hindié Franck Carreiras Hamanou Benachour Djahida Sidane Hafit Khireddine 《Journal of materials science. Materials in medicine》2016,27(9):140
A novel synthetic method to synthesize hydroxyapatite/poly (D,L) lactic acid biocomposite is presented in this study by mixing only the precursors hydroxyapatite and (D,L) LA monomer without adding neither solvent nor catalyst. Three compositions were successfully synthesized with the weight ratios of 1/1, 1/3, and 3/5 (hydroxyapatite/(D,L) lactic acid), and the grafting efficiency of poly (D,L) lactic acid on hydroxyapatite surface reaches up to 84?%. Scanning electron microscopy and Fourier transform infrared spectroscopy showed that the hydroxyapatite particles were successfully incorporated into the poly (D,L) lactic acid polymer and X ray diffraction analysis showed that hydroxyapatite preserved its crystallinity after poly (D,L) lactic acid grafting. Differential scanning calorimetry shows that Tg of hydroxyapatite/poly (D,L) lactic acid composite is less than Tg of pure poly (D,L) lactic acid, which facilitates the shaping of the composite obtained. The addition of poly (D,L) lactic acid improves the adsorption properties of hydroxyapatite for fibronectin extracellular matrix protein. Furthermore, the presence of poly (D,L) lactic acid on hydroxyapatite surface coated with fibronectin enhanced pre-osteoblast STRO-1 adhesion and cell spreading. These results show the promising potential of hydroxyapatite/poly (D,L) lactic acid composite as a bone substitute material for orthopedic applications and bone tissue engineering. 相似文献
9.
A popular approach in combinatorial optimization is to model problems as integer linear programs. Ideally, the relaxed linear
program would have only integer solutions, which happens for instance when the constraint matrix is totally unimodular. Still,
sometimes it is possible to build an integer solution with the same cost from the fractional solution. Examples are two scheduling
problems (Baptiste and Schieber, J. Sched. 6(4):395–404, 2003; Brucker and Kravchenko, J. Sched. 11(4):229–237, 2008) and the single disk prefetching/caching problem (Albers et al., J. ACM 47:969–986, 2000). We show that problems such as the three previously mentioned can be separated into two subproblems: (1) finding an optimal
feasible set of slots, and (2) assigning the jobs or pages to the slots. It is straigthforward to show that the latter can
be solved greedily. We are able to solve the former with a totally unimodular linear program, from which we obtain simple
combinatorial algorithms with improved worst case running time. 相似文献
10.
Hengyang Xiang Tingting Niu Mathilde Schoenauer Sebag Zhelu Hu Xiangzhen Xu Laurent Billot Lionel Aigouy Zhuoying Chen 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(16)
Photodetection in the short‐wave infrared (SWIR) spectrum is a challenging task achieved often by costly low bandgap compound semiconductors involving highly toxic elements. In this work, an alternative low‐cost approach is reported for SWIR sensors that rely on the plasmonic‐induced photothermal effect of solution‐processed colloidal gold nanorods (Au NRs). A series of uniform solution‐processed Au NRs of various aspect ratios are prepared exhibiting a strong and well‐defined longitudinal localized surface plasmon resonance (L‐LSPR) maximum from 900 nm to 1.3 µm. A hybrid device structure is fabricated by applying Au NRs on the surface of a thermistor. Under a monochromatic illumination, hybrid Au‐NR/thermistor devices exhibit a clear photoresponse in the form of photoinduced resistance drop in the wavelength window from 1.0 to 1.8 µm. The photoresponsivity of such hybrid devices reaches a maximum value of 4.44 × 107 Ω W?1 at λ = 1.4 µm (intensity = 0.28 mW cm?2), a wavelength in agreement with the L‐LSPR of the Au NRs applied. Colloidal Au NRs, capable to perform fast conversion between photon absorption and thermal energy, thus open an interesting avenue for alternative low‐cost SWIR photodetection. 相似文献