Combining Data Mining and Discrete Event Simulation for a value-added view of a hospital emergency department

While simulation models have furthered understanding of the operations of emergency departments (EDs) and the dynamics of the ED within the healthcare system, they only model patient treatment implicitly, tracing the paths patients follow through the ED. By identifying the core patient treatments provided by the ED and incorporating them into a Discrete Event Simulation model, this paper provides insight into the complex relationship between patient urgency, treatment and disposal, and the occurrence of queues for treatment. The essential characteristics of the presented model are used to indicate a generally applicable methodology for identifying bottlenecks in the interface between an ED and a hospital ward.     

Preparation and investigation of the composite based on superhigh-molecular poly(ethylene) and WO<Subscript>3</Subscript>

A composite based on superhigh-molecular poly(ethylene) and tungsten trioxide nanoparticles has been synthesized using the activation method. Tungsten nanoparticles have been prepared using the plasmachemical method and then oxidized in air. The particle size is 48 ± 7 nm. It has been established that the addition of tungsten nanoparticles to superhigh-molecular poly(ethylene) brings about changes in the arrangement of hydrocarbon chains in the structure, which leads to an improvement of the strength characteristics of the products.     

Analysis of transitions from autoionization states of the Bi III, Bi IV, and Bi V ions

The spectra of transitions from the autoionization states of bismuth ions are studied in the wavelength region from 170 to 500 Å. More than twenty transitions from the levels of configurations accompanied by excitation of the inner 5d subshell in the Bi V, Bi IV, and Bi III ions are identified and their autoionization widths are measured. In addition, transitions from the highly excited 5d ¹⁰ np levels (n=8–11) in the Bi V ion are identified and the ionization potential is refined.     

Synthesis of 6H-SiC single-crystal nanowires in a flow of carbon-silicon high-frequency arc plasma

Silicon carbide 6H-SiC nanoparticles and nanowires were obtained in carbon-silicon high-frequency arc plasma plasma in a helium atmosphere at a pressure of 0.1–0.6 MPa. It was shown that 6H-SiC nanowires grow from the arc plasma, as well as from the vapor, according to the known mechanism of vapor-solid condensation on a cold surface covered with single-crystal silicon carbide nuclei. The content of silicon carbide nanowires in the condensate reached 60 wt %. The obtained single-crystal silicon 6H-SiC nanowires had the diameter of 15–18 nm and length of 200–600 nm.     

Recording long-term potentiation of synaptic transmission by three-dimensional multi-electrode arrays

Background  

Multi-electrode arrays (MEAs) have become popular tools for recording spontaneous and evoked electrical activity of excitable tissues. The majority of previous studies of synaptic transmission in brain slices employed MEAs with planar electrodes that had limited ability to detect signals coming from deeper, healthier layers of the slice. To overcome this limitation, we used three-dimensional (3D) MEAs with tip-shaped electrodes to probe plasticity of field excitatory synaptic potentials (fEPSPs) in the CA1 area of hippocampal slices of 129S5/SvEvBrd and C57BL/6J-Tyr^C-Brd mice.     

Handling soft constraints via composite concave programming

In this discussion we propose a method for handling soft constraints in situations where the decision-maker can associate a cost function with the ‘right-hand side’ values of these constraints that satisfies the usual economies of scale property of decreasing marginal costs. The method constitutes a natural application of composite concave programming, and seems to be particularly suited for situations where the underlying problem is of the linear/quadratic programming type.     

Study of the interaction of argon and nitrogen ions with the silicon dioxide surface

Angular dependences of the sputtering yield, surface layer composition, and changes in the mass spectra of residual atmosphere upon irradiation of silicon dioxide with argon and nitrogen ions are measured. It is found that the sputtering yield of SiO₂ bombarded by N ₂ ⁺ ions is almost two times higher than for Si. The sputtering yields of SiO₂ and Si irradiated with Ar ions are identical, although the binding energy of atoms in SiO₂ is almost two times higher than in Si. An analysis of the surface composition and residual atmosphere near the sample during its irradiation suggests that a chemical reaction is involved in SiO₂ sputtering. Molecules of SiO and NO gases form in the surface layer, whose subsequent desorption increases the SiO₂ sputtering rate.     

Optimization of Steel-Surface Hardening by Carbon Nanostructures Followed by Treatment with High-Intensity Energy Sources

The effect whereby a steel surface is modified by its covering with a nanocarbon material followed by fast electron- or laser-beam irradiation is studied. The initial material is low-carbon steel. Soot produced via the thermal sputtering of graphite electrodes in an electric arc with the subsequent extraction of fullerenes is used as the nanocarbon coating. Due to the fact that nanocarbon-coated samples are irradiated with a 60-keV electron beam, the material microhardness enhances considerably. The dependence between the microhardness and the irradiation energy is nonmonotonic and reaches its maximum (about 600 ± 20 HV) under the condition that the electron-irradiation energy is 460 J/cm² and the intensity is 1.53 kW/cm². This corresponds to a fourfold increase in the microhardness. Electron-beam irradiation of the treated surface is accompanied by a 1.5–2-fold decrease in the friction coefficient. Experimental results are compared with data obtained under laser irradiation of the nanocarbon-coated steel surface.     

Numerical simulation of plastic deformation and damage accumulation in structural materials under various low-cycle loading conditions

This paper presents the results of a finite-element study of elastic-plastic deformation and damage accumulation in structural materials under various cyclic loading conditions. Material behavior is described by the relations of damage mechanics using thermoplastic model which takes into account the plastic deformation of material under cyclic loading and the kinetic equations of the energy theory of damage accumulation. The basic laws of plastic deformation and development of damage in materials under hard, soft, symmetric, and asymmetric low-cycle loading are established.     

Action of an elliptic stamp moving at a constant speed on an elastic half-space : PMM vol. 42, no. 6, 1978, pp 1074–1079

The action of a rigid stamp moving at a constant speed, on the boundary of an elastic half-space, is investigated. It is assumed that the frictional forces between the stamp and the surface of the half-space are absent. The integral equation obtained in [1] yields formulas for the pressure, for the case when the area of contact between the stamp and the half-space has an elliptic form.