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81.
Konstantin Todorov Nicolas James Céline Hudelot 《Multimedia Tools and Applications》2013,62(2):401-425
Ontologies have been intensively applied for improving multimedia search and retrieval by providing explicit meaning to visual content. Several multimedia ontologies have been recently proposed as knowledge models suitable for narrowing the well known semantic gap and for enabling the semantic interpretation of images. Since these ontologies have been created in different application contexts, establishing links between them, a task known as ontology matching, promises to fully unlock their potential in support of multimedia search and retrieval. This paper proposes and compares empirically two extensional ontology matching techniques applied to an important semantic image retrieval issue: automatically associating common-sense knowledge to multimedia concepts. First, we extend a previously introduced textual concept matching approach to use both textual and visual representation of images. In addition, a novel matching technique based on a multi-modal graph is proposed. We argue that the textual and visual modalities have to be seen as complementary rather than as exclusive sources of extensional information in order to improve the efficiency of the application of an ontology matching approach in the multimedia domain. An experimental evaluation is included in the paper. 相似文献
82.
Mokrab Y Bavro VN Mizuguchi K Todorov NP Martin IL Dunn SM Chan SL Chau PL 《Journal of molecular graphics & modelling》2007,26(4):760-774
We present two comparative models of the GABA(A) receptor. Model 1 is based on the 4-A resolution structure of the nicotinic acetylcholine receptor from Torpedo marmorata and represents the unliganded receptor. Two agonists, GABA and muscimol, two benzodiazepines, flunitrazepam and alprazolam, together with the general anaesthetic halothane, have been docked to this model. The ion flow is also explored in model 1 by evaluating the interaction energy of a chloride ion as it traverses the extracellular, transmembrane and intracellular domains of the protein. Model 2 differs from model 1 only in the extracellular domain and represents the liganded receptor. Comparison between the two models not only allows us to explore commonalities and differences with comparative models of the nicotinic acetylcholine receptor, but also suggests possible protein sub-domain interactions with the GABA(A) receptor not previously addressed. 相似文献
83.
M. N. Saprykina A. O. Samsoni-Todorov V. V. Todorov 《Journal of Water Chemistry and Technology》2009,31(5):329-333
Isolated were pathogenic micromycetes from tap drinking water among which the most typical were Aspergillus niger, Aspergillus flavus, Aspergillus ochraceus, Penicillum cyclopium, Penicillium expansum, Cladosporium cladosporioides. The article has studied inactivation of microscopic fungus by UV radiation. It has also established a series of sensitivity
of microorganisms to the effect of ultraviolet. It has been shown that such sanitary-indicative test microorganisms as Escherichia coli, Bacillius subtilis, Candida albicans cannot be used for assessing the degree of water decontamination by UV radiation by the mycological criterion. The stability
of micromycetes to UV radiation is an evidence of a necessity to use complex methods of water decontamination. 相似文献
84.
I. Naydenova L. Nikolova T. Todorov F. Andruzzi S. Hvilsted P. S. Ramanujam 《Journal of Modern Optics》2013,60(9):1643-1650
Abstract We investigate light propagation through materials with both linear and circular anisotropy and find the relation of the amplitude and polarization transfer functions to the four anisotropic characteristics: linear circular birefringence, and linear and circular dichroism. We determine these four characteristics of anisotropic samples by measuring the output intensity and polarization corresponding to different input polarization azimuths and fitting the theoretical and experimental results. In our experiments we have used films of side-chain azobenzene polyesters in which optical anisotropy had been previously induced on illumination with elliptically polarized light. 相似文献
85.
A theory for determining the existence, number and position of limit cycles in perturbed Hamiltonian systems, that depends on a small parameter, is presented. The limit cycle emerges from the periodic trajectories surrounding a centre of the unperturbed system. By means of this theory a sinusoidal oscillator with a nonlinear element has been analysed. It is shown that only the terms with odd degrees in the approximation polynomial of the nonlinear element's characteristic exert an influence on the initiation of limit cycles. 相似文献
86.
This work reports an in situ wide‐angle X‐ray scattering (WAXS) study of the structural evolution of PET with distinct initial morphologies during step uniaxial stretching in the solid state. Two types of samples were analyzed under synchrotron X‐ray radiation, namely quasi‐amorphous (QA) and semicrystalline (SC) (with 2D and 3D order). Results show that initially different QA morphologies evolve following the same stages: (i) stage I (before neck), at almost constant orientation level the amorphous phase evolves into mesophase; (ii) stage II (neck formation), there is a rapid increase of polymer orientation and the appearance of a periodical mesophase from the highly oriented mesophase; (iii) stage III (necking propagation), there is a leveling off of the average polymer orientation together with partial conversion of the periodical mesophase and mesophase into highly oriented amorphous. The behaviors of the two SC morphologies are completely distinct. A 2D order crystalline morphology evolves with stretching likewise the QA through three stages: (i) at early stages of deformation the polymer orientation remains unchanged while the amorphous phase amount increases slightly, stage I; (ii) in stage II, a fast increase of polymer orientation is accompanied by large formation of mesophase; and (iii) in stage III there is the level off of polymer orientation as the chains approach their finite extensibility and the 3D crystalline order is achieved. Evolution of SC sample with 3D crystalline order mainly features constant orientation increase together with mesophase increment. Structure deformation models are suggested. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
87.
Steven Marcus Wilfried Lerch Daniel F. Downey Stanislov Todorov Judy Chow 《Journal of Electronic Materials》1998,27(12):1291-1295
Ion implants of 2.0 and 5.0 keV 11B+ and 2.2, 5.0, and 8.9 keV 49BF
2
+
at a dose of 1E15/cm2 were investigated. Anneal conditions were developed which produced highly activated yet shallow junctions. The effects of
oxygen were studied previously by us1–12 and found to be an important variable to control in order to produce uniform and repeatable sheet resistance and junction
depths. A purge procedure and integrated oxygen sensor were developed to measure and control the oxygen background concentration
for each anneal to assure repeatable results. “Shelf-life,” that is dwell time between implant and anneal, was investigated.
It was found that, for low energy implants, the amount of native oxide grown affects retained dose, sheet resistance (Rs),
and uniformity. Controlled oxygen level repeatability and shelf life results are presented and equipment designs are discussed. 相似文献
88.
An analytical procedure based on L. M. Kachanov's model of fracture front propagation is examined. Its purpose is to predict
the fracture of sheet glass in the course of tempering. The conditions under which fracture is likely to take place and the
time to fracture are determined.
Translated from Steklo i Keramika No. 10, pp. 10–11, October, 1997. 相似文献
89.
Vladimir Ferdinandov Georgiev Todor Todorov Batakliev Metodi Parvanov Anachkov Slavcho Kirilov Rakovski 《臭氧:科学与工程》2015,37(1):55-61
The peculiarities of ozone absorption during olive oil ozonolysis have been studied by continuous monitoring of ozone concentrations at the bubbling reactor outlet. The determined amount of ozone, consumed during the ozonolysis of the double bonds, was used as alternative way for evaluation of the degree of unsaturation of the oil. The basic functional groups, products of the reaction: ozonides and aldehydes have been quantitatively characterized by means of 1H-NMR spectroscopy, whereupon their ratio was found to be 93.4:6.6 (mol. %), respectively. The determined ratio between the cis and trans ozonides was 46:54. 相似文献
90.
L. Nikolova T. Todorov M. Ivanov F. Andruzzi S. Hvilsted P.S. Ramanujam 《Optical Materials》1997,8(4):255-258
We report for the first time the inducing of large circular anisotropy in previously unoriented films of side-chain azobenzene polyesters on illumination with circularly polarized light at a wavelength of 488 nm. The circular dichroism and optical activity are measured simultaneously in real time at two wavelengths, 488 nm and 633 nm. The photoinduced optical activity has been measured to be 104 deg/cm and the circular dichroism has been found to be on the order of 0.3. 相似文献