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931.
Francisco Liébana-Cabanillas Francisco Muñoz-Leiva Juan Sánchez-Fernández María I. Viedma-del Jesús 《Information Systems and E-Business Management》2016,14(1):141-165
The aim of this paper is to contribute to the field of satisfaction research from the perspective of electronic banking users—a topic of great interest to financial institutions as they formulate business strategies. In this context, we analyze the possible moderating effect of user experience with the products of a specific institution. A comprehensive review of the scientific literature justified the development of a behavioral model that explains satisfaction using a set of constructs or endogenous variables and the moderating effect of experience. Data was collected from a self-administered Web survey in the authenticated section of the electronic banking service of a prestigious Spanish National financial institution. The analysis tests the relationship between the proposed variables (ease of access, trust, ease of use and usefulness) and demonstrates the moderating effect of electronic banking experience on them. The study was limited to the data of a single financial institution. Caution should therefore be exercised in generalizing the results. The research results provide a number of valuable conclusions for financial institutions. This paper is a pioneer study of satisfaction with electronic banking, especially with regard to the causal relationships between satisfaction and its main determinants. 相似文献
932.
Mariela Cerrada René-Vinicio Sánchez Fannia Pacheco Diego Cabrera Grover Zurita Chuan Li 《Applied Intelligence》2016,44(3):687-703
Feature selection is an important aspect under study in machine learning based diagnosis, that aims to remove irrelevant features for reaching good performance in the diagnostic systems. The behaviour of diagnostic models could be sensitive with regard to the amount of features, and significant features can represent the problem better than the entire set. Consequently, algorithms to identify these features are valuable contributions. This work deals with the feature selection problem through attribute clustering. The proposed algorithm is inspired by existing approaches, where the relative dependency between attributes is used to calculate dissimilarity values. The centroids of the created clusters are selected as representative attributes. The selection algorithm uses a random process for proposing centroid candidates, in this way, the inherent exploration in random search is included. A hierarchical procedure is proposed for implementing this algorithm. In each level of the hierarchy, the entire set of available attributes is split in disjoint sets and the selection process is applied on each subset. Once the significant attributes are proposed for each subset, a new set of available attributes is created and the selection process runs again in the next level. The hierarchical implementation aims to refine the search space in each level on a reduced set of selected attributes, while the computational time-consumption is improved also. The approach is tested with real data collected from a test bed, results show that the diagnosis precision by using a Random Forest based classifier is over 98 % with only 12 % of the attributes from the available set. 相似文献
933.
László Papp Matthias Sipiczki Imre J. Holb Ida Miklós 《Yeast (Chichester, England)》2014,31(12):475-482
The non‐pathogenic dimorphic fission yeast, Schizosaccharomyces japonicus, could be a suitable model organism for investigation of the genetic background of mycelial growth, as it has a haploid chromosome set and its genome is sequenced. Since earlier results have suggested that its morphological transition required solid substrates, but molecular biological experiments would require hyphae production in a liquid medium, we wanted to find circumstances which would enable hyphae production in liquid media. Several external conditions were investigated, but the strongest inducer was fetal bovine serum (FBS). Its positive effect could be hampered by heat and was dependent on pH, temperature and concentration of the serum. Other protein‐containing compounds, such as peptone and bovine serum albumin or amino acids, proved to be ineffective or weak. Generally, the uninduced and induced mycelial growth of Sz. japonicus could be improved by lower external pH and higher temperature. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
934.
M E SáNCHEZ-VERGARA V GARCíA-MONTALVO J SANTOYO-SALAZAR R J FRAGOSO-SORIANO O JIMéNEZ-SANDOVAL 《Bulletin of Materials Science》2012,35(5):759-766
NiPcTSTNa(L) [L = ethylenediamine (EDA); 1,4-diaminobutane (BDA); and 2,6-diamineanthraquinone (AqDA)] thin films were deposited by thermal evaporation. Their surface morphology was studied by AFM and SEM, and their chemical composition determined by EDS. Optical absorption studies of NiPcTSTNa(L) films were performed in the 200?C1150?nm wavelength range. The optical bandgap of thin films was determined from the (??h ??)1/2 vs h?? plots for indirect allowed transitions. The temperature dependence of electrical conductivity shows a semiconducting behaviour. The amorphous semiconductor films show thermal activation energies of electrical conduction between 3·3 and 3·7?eV. 相似文献
935.
Juan Gabriel Brida Juan Carlos Martín Concepción Román Raffaele Scuderi 《Networks and Spatial Economics》2017,17(3):911-934
Different solutions for the integration of high-speed rail (HSR) and air transport could be implemented, ranging from very basic integration to more sophisticated systems that include ticket and handling integration. This paper uses two statistical techniques, name cluster analysis and discrete choice models in order to investigate how different market segments have a determining influence in being more proactive to change to HSR for the second leg in multimodal trips. A discrete choice experiment is conducted to better understand passengers’ preferences. We obtain a number of clusters and estimate flexible choice models, taking into account the panel nature of stated preference data. We obtain a range of willingness-to-pay values for service quality attributes, finding results that can be used to infer policy conclusions about the real attractiveness of the Air-HSR integrated alternative. In this respect, clusters and schedule coordination, which reduces connecting time, are crucial to explain HSR attractiveness. 相似文献
936.
M. L. de la Torre J. A. Grande T. Valente M. Santisteban E. Pérez-Ostalé D. Sánchez-Rodas 《Mine Water and the Environment》2017,36(1):34-38
The El Sancho reservoir is located in the Odiel River basin, which crosses the Iberian Pyrite Belt. The reservoir receives acid mine drainage (AMD) from the Meca River, a tributary of the Odiel River. Two multi-parameter probes, one placed at the tail (up-gradient) end of the reservoir, where the contaminants enter, and another close to the reservoir dam were used to characterize acidity migration through the Sancho reservoir. The probes both measured pH and conductivity every 30 min. Two different levels of contamination were found, due to dilution that takes place within the reservoir and changes in the AMD composition. The cross-correlation function allowed quantification of the migration process from tail to dam. For both pH and conductivity, the maximum correlation occurred 17 days after sampling, indicating a mean transit time of 17 days. Since the distance between the two sampling points was 14,500 m, the contaminant transit speed was 0.0098 m/s. 相似文献
937.
938.
Himer Avila-George Jose Torres-Jimenez Nelson Rangel-Valdez Abel Carrión Vicente Hernández 《The Journal of supercomputing》2012,62(2):916-945
The Covering Arrays (CAs) are mathematical objects with minimal coverage and maximum cardinality that are a good tool for the design of experiments. A?covering array is an N×k matrix over an alphabet v s.t. each N×k subset contains at least one time each combination from {0,1,??,v?1} t , given a positive integer value?t. The process of ensuring that a CA contains each of the v t combinations is called verification of CA. In this paper, we present an algorithm for CA verification and its implementation details in three different computation paradigms: (a)?sequential approach (SA); (b)?parallel approach (PA); and (c)?Grid approach (GA). Four different PAs were compared in their performance of verifying a matrix as a CA; the PA with the best performance was included in a different experimentation where the three paradigms, SA, PA, and GA were compared in a benchmark composed by 45 possible CA instances. The results showed the limitations of the different paradigms when solving the verification of CA problem, and points out the necessity of a Grid approach to solve the problem when the size of a CA grows. 相似文献
939.
Santiago Iglesias-Pradas Pedro Fernández-Cardador 《Information Systems Management》2017,34(3):220-237
ABSTRACTThis study investigates employees’ acceptance of corporate Web 2.0 applications for collaboration and knowledge sharing. Results show that altruism, managerial support, and perceived usefulness are good predictors of the intention to use corporate blogs as tools for collaboration and knowledge sharing. The study further explores differences between employees from companies with low and high adoption rates, and uses prediction-oriented segmentation to unveil two different paths to adoption of Web 2.0 collaborative tools in companies. 相似文献
940.
Jan Racek Petr Šittner Luděk Heller Jan Pilch Martin Petrenec Petr Sedlák 《Journal of Materials Engineering and Performance》2014,23(7):2659-2668
Corrosion behavior of superelastic NiTi shape memory alloy wires with cracked TiO2 surface oxide layers was investigated by electrochemical corrosion tests (Electrochemical Impedance Spectroscopy, Open Circuit Potential, and Potentiodynamic Polarization) on wires bent into U-shapes of various bending radii. Cracks within the oxide on the surface of the bent wires were observed by FIB–SEM and TEM methods. The density and width of the surface oxide cracks dramatically increase with decreasing bending radius. The results of electrochemical experiments consistently show that corrosion properties of NiTi wires with cracked oxide layers (static load keeps the cracks opened) are inferior compared to the corrosion properties of the straight NiTi wires covered by virgin uncracked oxides. Out of the three methods employed, the Electrochemical Impedance Spectroscopy seems to be the most appropriate test for the electrochemical characterization of the cracked oxide layers, since the impedance curves (Nyquist plot) of differently bent NiTi wires can be associated with increasing state of the surface cracking and since the NiTi wires are exposed to similar conditions as the surfaces of NiTi implants in human body. On the other hand, the potentiodynamic polarization test accelerates the corrosion processes and provides clear evidence that the corrosion resistance of bent superelastic NiTi wires degrades with oxide cracking. 相似文献