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91.
Konstantoudakis Konstantinos Breitgand David Doumanoglou Alexandros Zioulis Nikolaos Weit Avi Christaki Kyriaki Drakoulis Petros Christakis Emmanouil Zarpalas Dimitrios Daras Petros 《Multimedia Tools and Applications》2022,81(9):12211-12250
Multimedia Tools and Applications - Immersive 3D media is an emerging type of media that captures, encodes and reconstructs the 3D appearance of people and objects, with applications in... 相似文献
92.
Chirag Modi Dhiren Patel Bhavesh Borisaniya Avi Patel Muttukrishnan Rajarajan 《The Journal of supercomputing》2013,63(2):561-592
Cloud computing offers scalable on-demand services to consumers with greater flexibility and lesser infrastructure investment. Since Cloud services are delivered using classical network protocols and formats over the Internet, implicit vulnerabilities existing in these protocols as well as threats introduced by newer architectures raise many security and privacy concerns. In this paper, we survey the factors affecting Cloud computing adoption, vulnerabilities and attacks, and identify relevant solution directives to strengthen security and privacy in the Cloud environment. 相似文献
93.
Delivery of sensitive water-soluble compounds in foods is an important challenge. (−)-Epigallocatechin-3-gallate (EGCG), the major catechin in green tea, is a potent antioxidant with numerous attributed health benefits. However, its sensitivity to oxidation limits its enrichment in the diet for preventive medicine. We have studied the possibility of using thermally modified β-lactoglobulin (β-Lg) to form co-assembled nanovehicles for delivery of EGCG, as a model system for delivery of polyphenols by heat-modified proteins. Using fluorescence spectroscopy, DLS and spectrophotometry we found that optimal nano-entrapment is obtained when EGCG is added to preheated (75–85 °C, 20 min) β-Lg solution during cooling and vortexing. The measured association constant with the heated protein was 3.7 × 105 M−1, about 3.5-fold higher than that with the native protein: 1.05 × 105 M−1. Thermally-induced protein-EGCG co-assemblies were smaller than 50 nm, thus excellent transparency was maintained, enabling their application in clear beverages. These complexes conferred considerable protection to EGCG against oxidative degradation: A 33-fold lower initial degradation rate, and a 3.2-fold slower degradation over 8 days were observed for nano-entrapped compared to unprotected EGCG. 相似文献
94.
Jet mills are common devices used in industry for fine milling of dry particulate materials. The size reduction is caused by repeated events of impacts between particles. Although many parameters affect the performance of a jet mill, only a few of them were investigated. Particles' motions in a jet mill have great influence on the comminution process and energy consumption. Therefore, as a first step for a full simulation of the jet-mill process, it was decided to investigate the particle motion inside the jet mill by neglecting particle-particle interaction and particle breakage. In this way, the numerical simulations provide a better understanding of the classification process. In the present study, three-dimensional numerical simulations of particle motion in an industrial full-scale jet mill were conducted. The predictions of the numerical simulations were compared with experimental data and used to analyze the flow field characteristics. 相似文献
95.
Using an object relations perspective, the representations of birth and adopted mothers in a sample of 52 nonreferred adoptees were studied. To better understand the specific effects of adoption or, the construction of 2 maternal representations, birth and adoptive maternal representation of adopted children was compared with that of nonadopted children. In addition, the effect of incongruous representations of birth and adoptive mothers on adoptees' exteralizing and internalizing behaviors was explored. Compared with nonadopted children, adoptees' representations of the mothers appear as more concrete and less benign. Among adopted children, representations of the birth mothers were found to contain split negative aspects of the adoptive mothers. Moreover, the differences between birth and adoptive mother representations were found to associate with adoptees'externalizing behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Chitosan/MWCNTs‐decorated with silver nanoparticle composites: Dielectric and antibacterial characterization 下载免费PDF全文
Julia Hernández‐Vargas J. Betzabe González‐Campos Javier Lara‐Romero E. Prokhorov Gabriel Luna‐Bárcenas Judit A. Aviña‐Verduzco Juan Carlos González‐Hernández 《应用聚合物科学杂志》2014,131(9)
The dielectric and biological properties of chitosan (CTS)‐based nanocomposites were analyzed by dielectric spectroscopy, and antibacterial and antifungal assays. Carbon nanotubes (CNT) and CNT decorated with silver nanoparticles (AgnP) were incorporated into a CTS matrix at different concentrations to obtain bionanocomposite thin films. The conductivity of pristine CTS is considerably enhanced, by six orders of magnitude, with the inclusion of CNT; however, with the addition of CNT decorated with AgnP it only increases by two orders of magnitude because of strong chemical interactions between the CNT and AgnP that also affect the antibacterial activity of the composite. The percolation threshold in the CTS/CNT composites is ca. 1.3 wt %, while in CTS/CNT‐AgnP composites the strong CNT‐AgnP chemical interactions give a percolation threshold of ca. 2.2 wt % of CNT‐AgnP. In both cases, DC conductivity exhibits a three‐dimensional hopping conductivity, and the σ‐ and α‐relaxation processes are disclosed in agreement with the pristine CTS relaxation processes previously reported; however, these two relaxations vanish in the vicinity of the saturation concentration. Finally, the antifungal activity of the CTS/CNT‐AgnP composites is comparable with the activity of other composites, while their antibacterial activity seems to be competitive with respect to commercial antibiotics, indicating the effectiveness of these composites in potential hygienic applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40214. 相似文献
97.
Zalevsky Z Rubner A García J Garcia-Martinez P Ferreira C Marom E 《Applied optics》2006,45(28):7325-7333
A joint transform correlator may suffer from overlapping of the zero diffraction order of the output, which does not contain relevant information, and the correlation peaks that appear in the first diffraction orders if objects are not sufficiently separated. Such overlapping significantly reduces the signal-to-noise ratio of the identification process. We propose a novel approach based on code division multiplexing technique in which the contrast of the identification peaks is significantly enhanced. The approach does not include placing the two objects side by side but rather includes code multiplexing them. Moreover, the code division multiplexing technique allows the space-bandwidth product to be improved. Optical implementation results are given. 相似文献
98.
This paper describes the methodology and application of a genetic algorithm scheme tailor-made to EPANET, for optimizing the operation of a water distribution system under unsteady water quality conditions. The water distribution system consists of sources of different qualities, treatment facilities, tanks, pipes, control valves, and pumping stations. The objective is to minimize the total cost of pumping and treating the water for a selected operational time horizon, while delivering the consumers the required quantities at acceptable qualities and pressures. The decision variables for each of the time steps that encompass the total operational time horizon include: the scheduling of the pumping units, settings of the control valves, and treatment removal ratios at the treatment facilities. The constraints are: head and concentrations at the consumer nodes, maximum removal ratios at the treatment facilities, maximum allowable amounts of water withdrawals at the sources, and returning at the end of the operational time horizon to a prescribed total volume in the tanks. The model is explored through two example applications. 相似文献
99.
100.
Knobloch Lynne M.; Endres Linda M.; Stiles William B.; Silberschatz George 《Canadian Metallurgical Quarterly》2001,38(1):31
Theme convergence is the linking of seemingly unrelated problem domains as they advance through assimilation stages-a developmental sequence of cognitive and affective changes through which problematic content is hypothesized to pass during successful psychotherapy. Theme divergence is the contradiction or conflict of solutions to different problems, so that progress in one domain leads to stagnation or regression in another domain. An intensive qualitative method called assimilation analysis was used to examine theme convergence and divergence in a successful psychodynamic psychotherapy with a 20–yr–old female patient. Because specific problems often fail to progress monotonically, even in successful psychotherapy cases, it is suggested that clients' problems cannot be resolved in isolation; instead, they may influence each other toward resolution or stagnation in complex and unpredictable ways. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献