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141.
Vujasinovic Marko Ivezic Nenad Kulvatunyou Boonserm Barkmeyer Edward Missikoff Michele Taglino Francesco Marjanovic Zoran Miletic Igor 《Internet Computing, IEEE》2010,14(1):52-63
The authors discuss a semantic-mediation architecture to advance traditional approaches for standards-based business-to-business (B2B) interoperability. The architecture is supported by the Athena Knowledge Representation and Semantics Mediation tool suite. Initial experimentations with the architecture and the toolset offer discussions of key architectural and functional aspects and suggest directions for future tools enhancements. 相似文献
142.
Anastasiya N. Mikhailova Galina P. Kayukova Igor P. Kosachev Irina I. Vandyukova Alexey V. Vakhin Georgy A. Batalin 《Petroleum Science and Technology》2018,36(17):1382-1388
Character of conversion of organic matter from Domanic rocks of Pervomaiskoye field (Tatarstan) of Semiluki horizon of upper Devonian deposits in the hydrothermal-catalytic system at temperature of 300?°C in carbon dioxide medium was studied with the application of complex of oil-soluble precursors of catalysts containing Fe, Co, and Cu. In presence of catalysts complex, content of organic extract increases, in which content of hydrocarbon fractions, saturated and aromatic hydrocarbons, increases 1.5 times, while resins content decreases by two times. As result of kerogen destruction in products of experiments, the content of asphaltenes and carbonaceous substances such as carbenes and carboides increase. 相似文献
143.
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145.
In this paper an improved neural network application for short-term load forecasting purposes is presented. To speed up the learning process on one side, and not to jeopardize the stability performance of the learning process on the other side, the adaptive approach to the learning-rate parameter has been employed. Also, instead of learning overall load characteristics, the preprocessing of input data has been designed with the idea to learn only load demand behavior that is important for a certain period. The proposed neural network has shown good performance, even in the case of the incomplete data temperature set and at high irregularities in weekly load data. 相似文献
146.
The influence of the microstructural inhomogenities in materials on the life-time of safety significant components of nuclear power plants is still not fully characterized. One of the most important sources of inhomogenities in metals is their grain structure. Differences in crystallographic orientations of grains lead to different responses under the applied loads and increased stresses at the grain boundaries. Engineering tools which are used to assess a response of a structural component to the applied loads are typically based upon the mechanics of continuum and are not able to account for these effects. Dedicated polycrystalline aggregate models are therefore being developed to study the effects of the microstructure on the load carrying capabilities of materials. However, a limited number of finite element types can be used due to the geometrical complexity of such models. A procedure for testing the behaviour of different finite elements in simulations involving explicit models of randomly shaped and oriented grains described by crystalline elasticity and crystal plasticity is therefore proposed. Cumulative distributions of the stress/strain tensors in all integration points in the model are compared, enabling comparison of the “average” (macroscopic) as well as “extreme” (local) behaviour of different meshes. Such an approach provides an easy to use probabilistic measure of the quality of results obtained using different element types, formulations and mesh densities. 相似文献
147.
Anton Trník Igor Štubňa Jana Moravčíková 《International Journal of Thermophysics》2009,30(4):1323-1328
The sound velocity of Sedlec kaolin during heating from 20 °C to 1100 °C was investigated by modulated force thermomechanical
analysis (mf-TMA). In the interval from 20 °C to 250 °C, the sound velocity increases which can be explained by liberation
of the water molecules from pores and micropores. Dehydroxylation (450 °C to 650 °C) presents itself with a decrease of the
sound velocity. After dehydroxylation, a two-step increase of the sound velocity was observed. The first step of the increase
of the sound velocity is due to solid-state sintering at low temperatures. The second step starts at 950 °C as a consequence
of the collapse of the metakaolinite structure. After the maximum, a steep increase of the sound velocity follows as a result
of solid-state sintering. 相似文献
148.
Hung-Hsuan Huang Aleksandra Cerekovic Igor S. Pandzic Yukiko Nakano Toyoaki Nishida 《AI & Society》2009,24(3):225-235
Embodied conversational agents (ECAs) are computer-generated, human-like characters that interact with human users in face-to-face
conversations. ECA is a powerful tool for representing cultural differences and is suitable for interactive training or edutainment
systems. This article presents preliminary results from the development of a culture-adaptive virtual tour guide agent for
serving Japanese, Croatian, and general Western users by displaying appropriate verbal and non-verbal behaviors. It is being
implemented in Generic ECA Framework, a modular framework for developing ECAs. Dividing the ECA functions into reusable and
loosely coupled modules minimizes the effort required to implement additional behavior and facilitates incremental scale up
of the system. 相似文献
149.
Yue Wang Georgios Tsiminis Ying Yang Arvydas Ruseckas Alexander L. Kanibolotsky Igor F. Perepichka Peter J. Skabara Graham A. Turnbull Ifor D.W. Samuel 《Synthetic Metals》2010,160(13-14):1397-1400
We report amplified spontaneous emission (ASE) and optically pumped deep-blue-emitting distributed feedback (DFB) lasers based on a star-shaped oligofluorene truxene molecule. A low ASE threshold of 2.1 kW/cm2 at 439 nm was achieved. The material exhibits a high net gain of 38 cm?1 and also low optical loss coefficient of 3.5 cm?1. Second-order DFB lasers show tuning of the emission wavelength from 422 to 473 nm, and a minimum threshold density of 515 W/cm2. This is the broadest tuning range (51 nm) reported for organic deep-blue/blue lasing materials. 相似文献
150.
Igor Luisetto Simonetta Tuti Elisabetta Di Bartolomeo 《International Journal of Hydrogen Energy》2012
Co/CeO2 (Co 7.5 wt.%), Ni/CeO2 (Ni 7.5 wt.%) and Co–Ni/CeO2 (Co 3.75 wt.%, Ni 3.75 wt.%) catalysts were prepared by surfactant assisted co-precipitation method. Samples were characterized by X-Ray diffraction, BET surface areas measurements, temperature programmed reduction and tested for the dry reforming of methane CH4 + CO2 → 2CO + 2H2 in the temperature range 600–800 °C with a CH4:CO2:Ar 20:20:60 vol.% feed mixture and a total flow rate of 50 cm3 min−1 (GHSW = 30,000 mL g−1 h−1). The bimetallic Co–Ni/CeO2 catalyst showed higher CH4 conversion in comparison with monometallic systems in the whole temperature range, being 50% at 600 °C and 97% at 800 °C. H2/CO selectivity decreased in the following order: Co–Ni/CeO2 > Ni/CeO2 > Co/CeO2. Carbon deposition on spent catalysts was analyzed by thermal analysis (TG-DTA). After 20 h under stream at 750 °C, cobalt-containing catalysts, Co/CeO2 and Co–Ni/CeO2, showed a stable operation in presence of a deposited amorphous carbon of 6 wt.%, whereas Ni/CeO2 showed an 8% decrease of catalytic activity due to a massive presence of amorphous and graphitic carbon (25 wt.%). 相似文献