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Doug Williams Marian F. Ursu Joshan Meenowa Pablo Cesar Ian Kegel Karl Bergström 《Telematics and Informatics》2011
This paper discusses results from research related to the use of television as a device that supports social interaction between close-knit groups in settings that include more than two locations, each location being potentially equipped with more than one camera. The paper introduces the notion of a framing experience, as a specific scenario or situation within which social communication takes place. It reports on the evaluation of some of the key attributes of social communication through semi-structured interviews, with 16 families across four European countries. The inferences drawn from this study are reduced to four system capabilities including the ability to support: excitement, engagement and entertainment; high quality, reliable audiovisual communications; flexibility and adaptability sufficient to support the unpredictable and reactive nature of human interaction and discourse. These system requirements are, in turn, reduced to a number of technology challenges which if solved will help enable effective social communications between groups, mediated by the television. These technology challenges include: high quality reliable audio visual communication; interaction orchestration, multimedia interpretation and multimedia composition. Finally the paper reflects on the impact the use of framing experiences, such as those described here, could have on strategy and policy for service providers and regulators. 相似文献
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Geta David Ioana Turin-Moleavin Laura-Elena Ursu Dragos Peptanariu Daniela Ailincai 《Iranian Polymer Journal》2018,27(7):517-526
Combining two or more materials for carrier construction is one of the topical approaches to avoid/diminish deficiencies and to increase functionality in delivery systems for bioactive compounds. In this context, here, multilayered nanoparticles comprising both natural (atelocollagen—AteCol; hyaluronic acid derivative—HA) and synthetic [poly(ε-caprolactone)—PCL; polyethylenimine—PEI; poly(l-lysine)—PLL] polymers were prepared and characterized. The combination of a modified double-emulsion method with polymer modification reactions allowed improvement of the polymer particle’s functionality. Fourier transform infrared spectroscopy (FTIR), UV–Vis spectroscopy, fluorescence spectroscopy, dynamic light scattering, transmission/scanning electron microscopy and fluorescence microscopy investigations confirmed the obtention of the envisaged nanomaterials with the expected composition and structure. The double-layered biopolymer/PCL-based nanoparticles formed in a first synthesis step could be successfully coated with PEI and PLL. The gel electrophoresis assay attested the DNA packing ability of the formed nano-vehicles involving surface grafting of the former biopolymer/PCL-based nanoparticles in the case of both cationic polymers, for N/P ratios of 10 (PEI coating) and 3.5 (PLL coating), respectively. According to the FTIR registration, the protein’s native form was preserved. Considering the advantage of biocompatibility and high versatility (controlled size, tuned chemistry and biodegradation rate) some of the resulted nanomaterials may appear as potential candidates for biomedical uses (i.e., drug/gene delivery and tissue engineering). 相似文献
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D. Z. Grabco O. A. Shikimaka M. Elisa B. A. Sava L. Boroica K. Pyrtsak A. Prisacaru Z. Danitsa I. Feraru D. Ursu 《Surface Engineering and Applied Electrochemistry》2012,48(4):365-374
The microstructure, as well as the mechanical and thermal properties, of phosphate glasses (PhGs) doped with rare earth elements (REEs), namely, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, and Yb, were studied in the present paper. The strength parameters of the PhGs and their dependence on the load value modification were estimated by the dynamic indentation method. Three specific stages were revealed in the deformation process, including nano-, submicro-, and microdeformation. The factors responsible for each stage were determined. It was shown that the strength properties (Young’s modulus and hardness) and the thermal characteristics (the lower and upper annealing temperature, the softening temperature, and the vitrification temperature) exhibit no evident relationship with the atomic mass and ionic radius of an REE. An assumption was made that the elastic and plastic properties of PhGs can be determined by the internal structure of the glasses. 相似文献
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The output parameters of an experimental fission electric cell (FEC) operating in the current generator mode have been estimated for the values of the neutron flux existing in the nuclear reactors. The estimation has been performed on the basis of the experimental values obtained in an investigation carried out at the Central Institute of Physcis (CIP) in Bucharest, Romania, concentrating on direct nuclear fission energy conversion into electrical energy. These experimental values are higher by orders of magnitude than those reported by other laboratories. The results of the estimation indicate that hundreds of microamperes, hundreds of kilovolts and hundreds of watts could be delivered by an FEC containing 1g of 235U and irradiated in a thermal neutron flux of 1.4 × 1013 neutron cm?2s?1. The research demonstrates the feasibility of efficient fission electric cells as potentially usable components in nuclear reactors. 相似文献
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A nonlinear programming optimization problem is considered for the case in which the decision vector is the vector of zonal irradiation while the objective function is the equilibrium fuel feed rate with a CANDU-600 reactor subject to certain restrictions regarding the reactivity excess and the maximum powers per channel and bundle. The objective and restriction functions of the system are estimated within a time average approximation of a three-dimensional two-group diffusion type, with the control systems uniformly immersed within the reactor, and also considering the newest increments of the parasitic absorbents using FMDP program. The optimization problem is solved by means of the SUMT method, modified so as to become a technique of sequential solving for certain subproblems of linear optimization through the application of LPROG program. The results are presented as optimal vectors of zonal irradiation and as optimal values of fuel feed rate, with some two-zone cases, which establish the best zonal configuration. This configuration is then extended to a four-zone case which is analysed in a similar manner, evidencing a saving potential which gives the possibiliy of increasing the reactor performance. 相似文献
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The 20Fe2O3 80[3B2O3·PbO] glasses equilibrated at 1250°C, for times ranging between 0.5 and 10 hrs are studied by X-rays, electron-microscope, Mössbauer effect, electron paramagnetic resonance and magnetic measurements. The iron valence states as well as the distribution of iron ions in the glass matrix are analysed. 相似文献