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1.
Although it is widely accepted that control mechanisms are necessary for human behavior to be adapted, very little is known about how such mechanisms are recruited. A suggestion to fill the gap was put forward by M. M. Botvinick, T. S. Braver, C. S. Carter, D. M. Barch, and J. D. Cohen (2001), who proposed the conflict-loop theory. This theory has been successful in accounting for the reduction of compatibility effects after an incompatible trial: The level of conflict being, on average, higher during an incompatible trial, more control occurs after such a trial. The authors have tested this prediction by sorting the trials on the basis of amount of conflict (quantified by the electromyographic activity) they presented. A reduction of the compatibility effect was observed after incompatible trials, but it was independent of the level of conflict on previous trials, suggesting that the conflict does not trigger changes in executive control. Consequences for the conflict monitoring model are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The high expectations and demand for users to access the Internet from anywhere at anytime has made user mobility an important part of the design and development of the next generation mobile communications and computing. Traditionally user mobility has been divided into two areas: Terminal Mobility and Personal Mobility. In recent years terminal mobility has focused on the movement of the terminal and developed extensions to IP protocols such as Mobile IP. In contrast, personal mobility has only received limited attention, and is somewhat lagging behind. This research has either focussed on personal mobility in communications or personalisation of operating environments. As a result, to date no framework for providing true personal mobility has emerged. In this paper, we introduce a new personal mobility framework called IPMoA (Integrated Personal Mobility Architecture), which integrates both aspects of personal mobility to provide a complete personal mobility solution, and illustrate the viability of this approach through a proof-of-concept implementation.  相似文献   
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The optical range of localized surface plasmon resonance (LSPR) is extended into the infrared region, thanks to the development of highly doped semiconductor nanocrystals. Particularly, the near-infrared (NIR) range holds a significant interest in managing solar radiation. However, practical applications necessitate the arrangement of particles, which is known to possibly impact their optical properties through LSPR coupling effects. How such coupling modifies the LSPR response in semiconductor hosts remains largely unexplored. In this study, a protocol for producing composite coatings composed of cesium-doped tungsten bronze nanocrystals embedded in a silica matrix is presented. Achieving individual dispersion of nanocrystals is made possible through careful selection of a surface polyglycerol ligand exchange. This allows to tune the interparticle distance by adjusting the nanocrystal volume fraction in the composite. The findings demonstrate that LSPR coupling effects significantly influence the LSPR intensity of nanocrystals in the composite when the nanocrystal-to-nanocrystal distance matches their size. Beyond elucidating the LSPR coupling effect, this study provides insights into the potential use of Cs-HTB nanocrystals for solar control applications. Through the optimization of morphology and film structure, remarkable selectivity is obtained in terms of maintaining good transparency in the visible range while achieving high absorption in the NIR.  相似文献   
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The development of an efficient fabrication route to achieve high-resolution perovskite pixel array is key for large-scale flexible image sensor devices. Herein, a high-resolution and stable 10 × 10 flexible PDs array based on formamidinium(FA+) and phenylmethylammonium (PMA+) quasi-2D (PMA)2FAPb2I7 (n = 2) perovskite is demonstrated by developing SiO2-assisted hydrophobic and hydrophilic treatment process on polyethylene terephthalate substrate. By introducing Au nanoparticles (Au NPs),  the perovskite film quality is improved and grain boundaries are reduced. The mechanism by which Au NPs upgrade the photoelectric quality of perovskite is mainly revealed by glow discharge-optical emission spectroscopy (GD-OES) and grazing-incidence wide-angle X-ray scattering (GIWAXS). To further improve the photoelectric performance of the devices, a post-treatment strategy with formamidinium chloride (FACl) is used . The optimized flexible PDs arrays show excellent optoelectronic properties with a high responsivity of 4.7 A W−1, a detectivity of 6.3 × 1012 Jones, and a broad spectral sensitivity. The device also exhibits excellent electrical stability even under severe bending and excellent flexural strength, as well as excellent environmental stability. Finally, the integrated flexible PDs arrays are used as sensor pixels in an imaging system to obtain high-resolution imaging patterns, demonstrating the imaging capability of the PDs arrays.  相似文献   
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We compare, in this paper, the far field radiated by two fractal distributions of current. The first one is obtained by a fractal cut following the Cantor arrangement, the second one keeps the length of each previous current element, but modifies the distance between the elements which is now taken as a constant. We establish the analytical formulations of the far field at any step n of the Cantor set. Then, we extract the array factor and we analyse and compare the following properties : convergence of the radiation pattern, wide of the main lobe, side lobes level and directivity.  相似文献   
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Functional electrical stimulation (FES) enables restoration of movement in individuals with spinal cord injury. FES-based devices use electric current pulses to stimulate and excite the intact peripheral nerves. They produce muscle contractions, generate joint torques, and thus, joint movements. Since the underlying neuromuscular-skeletal system is highly nonlinear and time-varying, feedback control is necessary for accurate control of the generated movement. However, classical feedback/closed-loop control algorithms have so far failed to provide satisfactory performance and were not able to guarantee stability of the closed-loop system. Because of this, only open-loop controlled FES devices are in clinical use in spite of their limitations. The purpose of the reported research was to design a novel closed-loop FES controller that achieves good tracking performance and guarantees closed-loop stability. Such a controller was designed based on a mathematical neuromuscular-skeletal model and is founded on a sliding mode control theory. The controller was used to control shank movement and was tested in computer simulations as well as in actual experiments on healthy and spinal cord injured subjects. It demonstrated good robustness, stability, and tracking performance properties.  相似文献   
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Ultrasonication is very effective in dispersing alumina and barium titanate slurries. When optimum conditions are used, very short durations (2 to 3 min) are enough to achieve well-dispersed, stable suspensions.  相似文献   
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