This work contributes to the development of ontology-based user models, devised as overlays over conceptual hierarchies derived from domain ontologies. We tackle the problem of propagation of user interests in such a conceptual hierarchy. In addition to accounting for the hierarchical structure of the domain and the type and amount of feedback provided by the user, the principal contributions i...

Laser filamentation produced by the propagation of intense laser pulses in flames is opening up new possibility in application to combustion diagnostics that can provide useful information on understanding combustion processes, enhancing combustion efficiency and reducing pollutant products. Here we present simultaneous identification of multiple combustion intermediates by femtosecond filament...

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Nanocrystalline ZrO2 with particle size of about 38 nm was directly synthesized by sol-gel auto-combustion method. The overall process involved three steps: formation of homogeneous sol at 50-55°C; formation of dried gel at 110°C, and combustion of the dried gel at 400°C. Experiments revealed that ZrO2 dried gel derived from glycine (Fuel) and nitrate sol exhibited self pr...

The design and development of modern internal combustion engines are marked by a reduction in exhaust gas emissions and increase in specific power and torque. Correspondingly, combustion noise excitation and fuel consumption also have to be reduced. These objectives can be achieved through the development of advanced combustion systems, the increased flexibility of fuel injection systems and EC...

Mesoscale internal combustion engines for a variety of new combustion system applications have dimensions that are far smaller than conventional macroscale engines, yet unlike true microscale engines allow significant mean flow and turbulence to be created in the combustion chamber by the injection process. The resulting flow allows minimization of the combustion time by augmenting flame propag...

A novel combustion mode, namely tri-fuel (TF) using a diesel pilot to ignite the premixed methane–hydrogen–air (CH4–H2–air) mixtures, was experimentally investigated under various H2 fractions (0%, 10%, 20%, 40%, 60%) and ultra-lean conditions (equivalence ratio of φ= 0.5). The overarching objective is evaluate effect fraction on flame characteristics engine performance. To visualize process ch...

Residential combustion has been identified as one of the main sources of particulate matter (PM); fine particles are important because of their adverse effects on human health and the environment. In this thesis, fine particle emissions originating from residential pellet combustion were characterized in different operational situations and using different raw materials as pellet fuel. Moreover...

Control of the inner engine torque of a combustion engine is very crucial for the overall performance of a dynamical combustion engine test bench. The main problem thereby is the usually unknown system behavior of the combustion engine, the time delay of the accelerator actuator which is used to control the combustion engine. In general the combustion engine is mounted on a combustion engine te...