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41.
Ertan Onur Yunus Durmus Mohamed Gamal Hawas Sonia Marcela Heemstra de Groot Ignas G. M. M. Niemegeers 《Wireless Personal Communications》2011,58(1):71-93
In this paper, we present a visionary concept referred to as Collaborative and Cognitive Network Platforms (CCNPs) as a future-proof
solution for creating a dependable, self-organizing and self-managing communication substrate for effective ICT solutions
to societal problems. CCNP creates a cooperative communication platform to support critical services across a range of business
sectors. CCNP is based on the personal network (PN) technology which is an inherently cooperative environment prototyped in
the Dutch Freeband PNP2008 and the European Union IST MAGNET projects. In CCNP, the cognitive control plane strives to exploit
the resources to better satisfy the requirements of networked applications. CCNP facilitates collaboration inherently. Through
cognition in the cognitive control plane, CCNP becomes a self-managed substrate. The self-managed substrate, in this paper,
is defined as cognitive and collaborative middleware on which future applications run without user intervention. Endemic sensor
networks may be incorporated into the CCNP concept to feed its cognitive control plane. In this paper, we present the CCNP
concept and discuss the research challenges related to collaboration and cognition. 相似文献
42.
Many studies have found smokers' quit history to correlate with quitting smoking, but little is known about the psychological processes explaining this relationship. This study uses the integrative model of behavioral prediction to examine how quit history affects quit intention. Data from 3,428 Dutch smokers demonstrate that quit history affects (a) beliefs about quitting and (b) the degree to which self-efficacy predicts quit intention. It seems that a relatively unsuccessful history of prior quit attempts reduces self-efficacy over quitting and strengthens the relationship of self-efficacy with the intention to quit. The results are used to call for more process-oriented research in order to advance our understanding of the relationship between quit history and quit intention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Edzer Huitema Gerwin Gelinck Bas van der Putten Eugenio Cantatore Karel Kuijk Kees Hart Dago De Leeuw 《Journal of the Society for Information Display》2002,10(3):195-202
A 2‐in. active‐matrix display was demonstrated, containing 4096 solution‐processed polymer‐based transistors. By using the polymer‐dispersed liquid‐crystal display (LCD) effect, this results in a reflective, low‐power display with paper‐like contrast. The influence of the transistor parameters on the display performance is analyzed by use of a model for charging and discharging of the pixel capacitors. Good agreement was obtained between the model and the experimental data. Scaling behavior allows estimation of the performance required for transistors in a quarter‐VGA display. These requirements are met by solution‐processed pentacene transistors. 相似文献
44.
Gelinck GH Huitema HE van Veenendaal E Cantatore E Schrijnemakers L van der Putten JB Geuns TC Beenhakkers M Giesbers JB Huisman BH Meijer EJ Benito EM Touwslager FJ Marsman AW van Rens BJ de Leeuw DM 《Nature materials》2004,3(2):106-110
At present, flexible displays are an important focus of research. Further development of large, flexible displays requires a cost-effective manufacturing process for the active-matrix backplane, which contains one transistor per pixel. One way to further reduce costs is to integrate (part of) the display drive circuitry, such as row shift registers, directly on the display substrate. Here, we demonstrate flexible active-matrix monochrome electrophoretic displays based on solution-processed organic transistors on 25-microm-thick polyimide substrates. The displays can be bent to a radius of 1 cm without significant loss in performance. Using the same process flow we prepared row shift registers. With 1,888 transistors, these are the largest organic integrated circuits reported to date. More importantly, the operating frequency of 5 kHz is sufficiently high to allow integration with the display operating at video speed. This work therefore represents a major step towards 'system-on-plastic'. 相似文献
45.
46.
Onur Eser Semra Kurama Goktug Gunkaya 《Journal of the European Ceramic Society》2010,30(14):2985-2990
In the present work nano-sized powder of β-SiAlON was produced using a wet milling process. Different milling times and mediums (methyl ethyl keton, ethanol and toluene as solvents, polyethyleneglicol, oleic acid, sodium tripolyphosphate and polyvinylpyrrolidon as dispersants) were performed for the determination of the most efficient milling system. The powders were produced using a conventional process (the ball to powder ratio was 1:1.5, at 300 rpm, for 1.5 h) having a few hundred nanometer particle size, and these were used as standard powders in this study. The nano-sized β-SiAlON starting powders (<100 nm) were sintered at lower temperatures than that of the conventional powders. The amount of Y2O3 in powders (~130 nm), produced by high energy milling process, was fewer than conventional powders (5 wt.%). The results of the powder size, sintering behavior and mechanical properties of this sample were compared to those of the standard powder and its sintered sample. This sample, produced using the nano-powder, was investigated, and densified at 150 °C lower than that of the standard sample. Even though the amount of Y2O3 was decreased, the hardness of the samples was better than that of the standard sample. 相似文献
47.
Optimization of Multireservoir Systems by Genetic Algorithm 总被引:1,自引:1,他引:0
Application of optimization techniques for determining the optimal operating policy of reservoirs is a major issue in water
resources planning and management. As an optimization Genetic Algorithm, ruled by evolution techniques, have become popular
in diversified fields of science. The main aim of this study is to explore the efficiency and effectiveness of genetic algorithm
in optimization of multi-reservoirs. A computer code has been constructed for this purpose and verified by means of a reference
problem with a known global optimum. Three reservoirs in the Colorado River Storage Project were optimized for maximization
of energy production. Besides, a real-time approach utilizing a blend of online and a posteriori data was proposed. The results
obtained were compared to the real operational data and genetic algorithm was found to be effective and can be utilized as
an alternative technique to other traditional optimization techniques. 相似文献
48.
Rokers Bas; Mercado Eduardo III; Allen M. Todd; Myers Catherine E.; Gluck Mark A. 《Canadian Metallurgical Quarterly》2002,116(1):48
Septohippocampal interactions determine how stimuli are encoded during conditioning. This study extends a previous neurocomputational model of corticohippocampal processing to incorporate hippocamposeptal feedback and examines how the presence or absence of such feedback affects learning in the model. The effects of septal modulation in conditioning were simulated by dynamically adjusting the hippocampal learning rate on the basis of how well the hippocampal system encoded stimuli. The model successfully accounts for changes in behavior and septohippocampal activity observed in studies of the acquisition, retention, and generalization of conditioned responses and accounts for the effects of septal disruption on conditioning. The model provides a computational, neurally based synthesis of prior learning theories that predicts changes in medial septal activity based on the novelty of stimulus events. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
This study characterizes surface treated classic type fiber metal laminates (FMLs) interlaminar shear strength (ILSS) based on a glass mat reinforced polyphenylene sulphide composite and an aluminum alloy. The effect of concentration of γ‐glycidoxypropyltrimethoxysilane surface treatment on ILSS of adhesive bonding between aluminum sheet and composite laminates has been investigated. After determining the silane concentration, novel FML material is manufactured using a compression moulding process which involves aluminum sheets with different circular hole perforations (Array type A and B) with two circular hole diameters (ϕ3 and ϕ5 mm) and two total hole area/closed area: 0.05 and 0.06) to develop mechanical interlocking between aluminum layers and composite laminates. Tensile tests are performed to investigate the effect of different circular hole perforations on ILSS properties of FMLs. Test results show that ILSS is improved with increasing the circular hole diameter and decreased with the number of holes as correlated with undrilled FMLs. Failure modes, damage initiation, and progression of FMLs with different open hole perforations are determined with optical microscope. POLYM. COMPOS., 37:963–973, 2016. © 2014 Society of Plastics Engineers 相似文献
50.
Zülküf Genç Umar H. Rizvi Ertan Onur Ignas Niemegeers 《Wireless Personal Communications》2010,53(3):349-364
The basic idea behind cooperative communications is that mobile terminals collaborate to send data to each other. This effectively
adds diversity in the system and improves the overall performance. In this paper, we investigate the potential gains of cooperative
communication in future home networks. We derive analytical expressions for the error probability of binary phase shift keying
(BPSK) signals over Nakagami-m fading channels in a multi relay communication network. Following to the analytical study, we analyze the contribution of
cooperative relaying to the 60GHz network connectivity through simulations using a realistic indoor environment model. We
compare the performance of different relay configurations under variable obstacle densities. We show that a typical 60GHz
indoor network should employ either a multi-relay configuration or a single-relay configuration with a smart relay selection
mechanism to achieve acceptable outage rates. In the use of multiple-relay configuration, both analytical and simulation studies
indicate that increasing the number of cooperative relays does not improve the system performance significantly after a certain
threshold. 相似文献