Formulating the template ILP consistency problem as a constraint satisfaction problem

Inductive Logic Programming (ILP) deals with the problem of finding a hypothesis covering positive examples and excluding negative examples, where both hypotheses and examples are expressed in first-order logic. In this paper we employ constraint satisfaction techniques to model and solve a problem known as template ILP consistency, which assumes that the structure of a hypothesis is known and the task is to find unification of the contained variables. In particular, we present a constraint model with index variables accompanied by a Boolean model to strengthen inference and hence improve efficiency. The efficiency of models is demonstrated experimentally.     

A comparison between tracer gas and aerosol particles distribution indoors: The impact of ventilation rate,interaction of airflows,and presence of objects

The study investigated the separate and combined effects of ventilation rate, free convection flow produced by a thermal manikin, and the presence of objects on the distribution of tracer gas and particles in indoor air. The concentration of aerosol particles and tracer gas was measured in a test room with mixing ventilation. Three layouts were arranged: an empty room, an office room with an occupant sitting in front of a table, and a single‐bed hospital room. The room occupant was simulated by a thermal manikin. Monodisperse particles of three sizes (0.07, 0.7, and 3.5 μm) and nitrous oxide tracer gas were generated simultaneously at the same location in the room. The particles and gas concentrations were measured in the bulk room air, in the breathing zone of the manikin, and in the exhaust air. Within the breathing zone of the sitting occupant, the tracer gas emerged as reliable predictor for the exposure to all different‐sized test particles. A change in the ventilation rate did not affect the difference in concentration distribution between tracer gas and larger particle sizes. Increasing the room surface area did not influence the similarity in the dispersion of the aerosol particles and the tracer gas.     

Magnetic anisotropy in intermetallic compounds containing both uranium and 3d-metal

Magnetic properties of intermetallic compounds containing both uranium and a 3d metal (Fe, Co) are summarized and discussed. It was shown that the ordered magnetism of the U and 3d-metal sublattices can coexist in the same compound (e.g. with 2–17 and 1–12 stoichiometries) even at room and elevated temperatures.     

The Distribution of Antimony and Arsenic in Waters of the Dúbrava Abandoned Mine Site, Slovak Republic

The abandoned Dúbrava Mine, situated in the northern part of the Nízke Tatry Mts in the middle of Slovakia, was the most significant producer of antimony (Sb) in the former Czechoslovakia. Mine drainage from adits (containing up to 9,300 μg/L of Sb), mine waste dumps, and the leachate from mine tailings contribute Sb and arsenic (As) into nearby Palud?anka Creek and groundwater. Some drinking water resources have been closed due to excessive Sb concentrations; the concentration of Sb in one household well (126 μg/L) far exceeds the Sb drinking water limit of 5 μg/L. Although Sb is attenuated by dilution and adsorption on ferric iron in stream sediment in the Palud?anka Creek, Sb concentrations increase downstream of the mine tailings and then remain almost constant, leading to concentrations of 128 μg/L at the northern boundary of the study area. The dissolved As concentrations in the mine drainage are much lower than Sb, ranging from 4 to 62 μg/L. Flow and transport modeling confirmed the observed contamination pattern and the major role of the mine adits. Results of this study indicate serious Sb contamination, which could be mitigated by treatment of the adit discharges.     

Combined single domain and subdomain BEM for 3D laminar viscous flow

A subdomain boundary element method (BEM) using a continuous quadratic interpolation of function and discontinuous linear interpolation of flux is presented for the solution of the vorticity transport equation and the kinematics equation in 3D. By employing compatibility conditions between subdomains an over-determined system of linear equations is obtained, which is solved in a least squares manner. The method, combined with the single domain BEM, is used to solve laminar viscous flows using the velocity vorticity formulation of Navier–Stokes equations. The versatility and accuracy of the method are proven using the 3D lid driven cavity test case.     

Three-dimensional numerical simulation of the exhaust stroke of a single-cylinder four-stroke ICE

In this paper an extensive CFD simulation of the exhaust stroke of a single-cylinder fourstroke ICE, including the entire exhaust manifold is described. Guidelines for the implementation of the full threedimensional model of the discussed process are included. The simulation involves the time-dependent flow of exhaust gases through the exhaust valve and the flow dynamics within the 2.2-m-long, straight exhaust pipe during the period when the valve is closed. Also the intake port with the intake valve is being coupled during the valves’ overlap period. The model geometry corresponds exactly to the actual engine geometry. The movement of the mesh follows the measured kinematics of the piston and the valves. The data obtained from the experimental environment was used for both the initialization and the validation of the computations. It was found that the phenomena affecting the dynamics of the exhaust flow are extremely three-dimensional and should be treated as such. In particular, the flow through the exhaust valve and the heat transfer along the exhaust pipe were influenced greatly by the effects of cold, fresh air breaking into the exhaust pipe in the period after the EVC. The presented study is the basis for future three-dimensional investigations of the entropy-generation rate along the exhaust system, including the exhaust valve.     

Volumetric Properties, Viscosities, and Refractive Indices of the Binary Systems 1-Butanol + PEG 200, + PEG 400, and + TEGDME

Densities, viscosities, and refractive indices of three binary systems consisting of 1-butanol with polyethylene glycols of different molecular weights (PEG 200 and PEG 400) or tetraethylene glycol dimethyl ether (TEGDME) were measured at ten temperatures (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, 318.15, 323.15, 328.15, and 333.15) K and atmospheric pressure. Densities of the selected binary mixtures were measured with an Anton Paar DMA 5000 digital vibrating U-tube densimeter, refractive indices were measured with an automatic Anton Paar RXA-156 refractometer, while for viscosity measurements, a digital Stabinger SVM 3000/G2 viscometer was used. From these data, excess molar volumes were calculated and fitted to the Redlich–Kister equation. The obtained results have been analyzed in terms of specific molecular interactions and mixing behavior between mixture components, as well as the influence of temperature on them. Viscosity data were also correlated by Grunberg–Nissan, Eyring–UNIQUAC, three-body McAlister, and Eyring–NRTL models.     

Crystal structure studies on plate/shelf like disodium ditungstate

The structure of plate/shelf like disodium ditungstate (Na₂W₂O₇) synthesized by new method in the process of ultrasonic spray pyrolysis using acidified aqueous solutions of tungsten (VI) oxide clusters as a precursor was refined down to the R-factor of 8.9 %. X-ray diffraction analysis undoubtedly confirmed formation of orthorhombic Na₂W₂O₇ and refinement of the diffraction data showed that Na₂W₂O₇ powder belongs to the base-centred orthorhombic type of structure with 64 space group, Cmca. The structure of Na₂W₂O₇ can be described as infinite chains formed from tetrahedral (WO₄) and octahedral (WO₆) building units joined together. It was found that the basic units of the precursor complexes exist in the structure of Na₂W₂O₇. Scanning electron microscopy confirmed formation of plate/shelf like Na₂W₂O₇ particles with an average thickness of about 1.2 μm.     

Fuzzy gain-scheduling control of a gas-liquid separation plant implemented on a PLC

In the paper an approach to the non-linear control of a gas-liquid separation plant is presented. To solve the problem the fuzzy gain-scheduling method was used and implemented on a programmable logic controller (PLC). Velocity-based linearization approach was used for control system design and implementation for the first time in process control application. Emphasis was placed on the appropriate adaptation of the method and some important implementation issues. The algorithm was carefully designed and tested by using ordinary simulation, hardware-in-the-loop simulation, and experiments on the real plant. The results show that the proposed approach substantially improves the closed-loop performance of the plant.