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961.
Scientometrics - If scholars suffer from imperfect attention, they will not always cite the best paper on a particular topic. The most chosen scholarly works may merely be the most cited ones, not... 相似文献
962.
García J. A. Rodriguez-Sánchez Rosa Fdez-Valdivia J. Chamorro-Padial Jorge 《Scientometrics》2019,121(3):1435-1445
Scientometrics - How much does it cost to publish a research article in a scholarly journal? Different academic publishers have widely varying levels of publication fees to help to fund editorial... 相似文献
963.
Scientometrics - Pharmacoeconomy is a young interdisciplinary science at the intersection of pharmacy, medicine and economics, focusing on the social aspects and implications of different types of... 相似文献
964.
Ayşegül Güven 《中国工程学刊》2019,42(4):357-365
Diagnostic efforts to identify alcoholism are frequently subjective; however, recent technological advances have allowed the automated assessment of objective signals. To improve the performance of the automated classification of patients with alcohol dependence (AD) and controls, we analyzed features of event-related potentials (ERPs) in 72 subjects with AD and 42 controls while the subjects underwent three different visual oddball tasks. In addition to such commonly used morphological features (MFs) as time-domain amplitude and latency components as well as discrete wavelet transform coefficient entropies (WEs), we analyzed Hu moment invariants (HMIs) in this study. Smaller P3 and P2 amplitudes, longer latencies, lower WE values, and lower HMI values were observed for AD subjects relative to those observed for controls. We used a Naïve Bayes algorithm to compare classification accuracies among MFs, WEs, HMIs, combinations of MFs/WEs, and combinations of all three characteristics. We found that HMIs improved the classification accuracy by 17%. Our findings demonstrated that a combined feature analysis of ERPs obtained during a visual oddball task can be a useful and discriminative tool for diagnostic purposes in alcoholism and that HMIs show promise for improving the objective diagnosis of alcoholism and similar diseases. 相似文献
965.
Jiří Bednář Ladislav Svoboda Pavel Mančík Richard Dvorský 《Materials Science & Technology》2019,35(7):775-781
Zinc sulphide (ZnS) nanoparticles were prepared by an aerosol method from zinc acetate and sodium sulphide (Na2S) aqueous solutions. Aqueous solution of zinc acetate was dispersed into the form of microdroplets, which were introduced by airflow to vigorously stirred aqueous solution of Na2S, which was in excess. Microdroplets served as microreactors, so the reaction took place only in limited volume. Particle size distribution was studied by transmission electron microscopy and by dynamic light scattering measurements. In this work, the equation that allows us to predict the final size distribution of ZnS nanoparticles using exact concentration of zinc acetate was derived and ZnS nanoparticles with predicted mean particle diameter around 50 and 70?nm were successfully synthetised. 相似文献
966.
967.
Maria Pemartín Gregorio Sánchez-Marín José Luis Munuera-Alemán 《Industry and innovation》2019,26(1):57-77
Since new product development (NPD) collaborations with external partners have become the next generation in NPD practices, relationship promoters have become especially relevant as key contributors to the success of this type of inter-organisational collaboration. To realise successful outcomes in NPD collaborations, partners face the challenge of effectively integrating the role of relationship promoter into their existing and essential relationships of trust. It is within this context that this paper examines the role of the relationship promoter, by analysing its moderating effect on the relationship between trust and the outcomes of NPD collaboration – including new product competitiveness and partner satisfaction. We test our hypotheses against survey data from 107 innovative firms involved in NPD collaboration with the help of relationship promoters. The results show that, while a non-significant influence can be reported about the presence of a relationship promoter in terms of partner satisfaction, the relationship promotor weakens the influence of trust on new product competitiveness, making trust less important when it comes to creating a competitive new product. 相似文献
968.
Omar Hernández-González Mondher Farza Tomas Ménard Mohammed M'Saad Rogelio Lozano 《International journal of systems science》2019,50(5):1089-1105
This paper proposes a new high gain observer for a class of non-uniformly observable nonlinear systems with coupled structure driven by sampled outputs. The considered class of systems is particularly constituted by several subsystems where each subsystem is associated to a subset of the output variables. The observer design is carried out through two steps. First, a high-gain observer is proposed in the continuous-time output case under the assumption that an adequate persistent excitation condition is satisfied by each subsystem. Then, the proposed observer is redesigned to handle the case of sampled outputs leading thereby to a continuous-discrete time observer. The latter property is achieved thanks to the approach pursued along the convergence analysis. The effectiveness of the proposed observer is emphasised in a realistic simulation framework involving a mathematical model of a quadrotor which is diffeomorphic to the proposed class of considered systems. 相似文献
969.
Materials Science - The nonstationary thermal state of a thermally sensitive multilayer plate is described by a nonlinear boundary-value problem with discontinuous coefficients. The method proposed... 相似文献
970.
Materials Science - It is shown that the numerical analyses of slab reinforced concrete structures are, as a rule, based on the classical theory of bending of elastic plates. According to the... 相似文献