A User Level Markov model for service based CRRM algorithm

In order to support the conceptual development of Radio Access Technology (RAT) selection algorithms, the theory of Markov model has been used. Performance metrics can be derived from the steady state probabilities of a Markov model. This paper extends a User Level Markov model for a three co-located RATs system from existing two co-located RATs Markov models. The service based RAT selection algorithm has been studied using the proposed Markov model. Numerical results obtained from the proposed Markov model are presented. ©2010 IEEE

Model-based Probe State Estimation and Crack Inverse Methods Addressing Eddy Current Probe Variability

Recent work on model-based inverse methods with eddy current inspections of surface breaking discontinuities has shown some sizing error due to variability in probes with the same design specifications [1]. This is an important challenge for model-based inversion crack sizing techniques, to be robust to the varying characteristics of eddy current probes found in the field [1-2]. In this paper, a model-based calibration process is introduced that estimates the state of the probe. First, a carefully designed surrogate model was built using VIC-3D® simulations covering the critical range of probe rotation angles, tilt in two directions, and probe offset (liftoff) for both tangential and longitudinal flaw orientations. Some approximations and numerical compromises in the model were made to represent tilt in two directions and reduce simulation time; however, this surrogate model was found to represent the key trends in the eddy current response for each of the four probe properties in experimental verification studies well. Next, this model was incorporated into an iterative inversion scheme during the calibration process, to estimate the probe state while also addressing the gain/phase fit and centering the calibration notch indication. Results are presented showing several examples of the blind estimation of tilt and rotation angle for known experimental cases with good agreement within +/- 2.5 degrees. The RMS error was found to be significantly reduced by fitting the probe state and, in many instances, probe state estimation addresses the previously un-modelled characteristics (model error) with real probe inversion studies. Additional studies are presented comparing the size of the calibration notch and the quality of the calibration fit, where calibrating with too small or too large a notch can produce poorer inversion results. Once the probe state is estimated, the final step is to transform the base crack inversion surrogate model and apply it for crack characterization. Because of the dimensionality of this problem, simulations were made at a limited set of select flaw sizes with varying length, depth and width, and an interpolation scheme was used to address the effect of the probe state at intermediate solution points. Using this process, results are presented demonstrating improved crack inversion performance for extreme probe states

Microstructural analysis of siderurgical aggregate concrete reinforced with fibers

The development of cracks in concrete structures is one of the significant issues with maintaining high strength after hardening. One way to prevent and control this problem is to use fibers. This paper investigates concrete containing electric arc furnace slag aggregates reinforced with fibers. The fibers used in this study are steel fibers and three kinds of polypropylene fibers; polyolefin fibers (modified polypropylene), polypropylene homopolymer, and high-toughness polypropylene. By checking the compressive and flexural strength of concretes made with fibers, it can be seen that the best results at 28 days are found for concrete with steel fibers, namely 62 MPa with 0.9% of fibers. On the contrary, the lowest values are for concrete containing polyolefin fibers, 51 MPa, and the same percentage of fibers. Additionally, under flexural strength testing, at the age of 28 days, the strength of these samples with 0.9% of fibers was 9.54 MPa, a value that is comparable to test concrete with the same percentage of steel fibers, 10.67 MPa, despite the low workability of concrete containing polyolefin fibers with a slump of 25 mm. Moreover, the boundary transition area analysis shows that the excellent connection between the fibers and cement paste near the siderurgical aggregate has caused no cracks in this area. In contrast, cracks can be observed in critical areas near the natural aggregates

The role of the neutral beam fueling profile in the performance of the Tokamak Fusion Test Reactor and other tokamak plasmas

Scalings for the stored energy and neutron yield, determined from experimental data are applied to both deuterium-only and deuterium-tritium plasmas in different neutral beam heated operational domains in Tokamak Fusion Test Reactor. The domain of the data considered includes the Supershot, High poloidal beta, Low-mode, and limiter High-mode operational regimes, as well as discharges with a reversed magnetic shear configuration. The new important parameter in the present scaling is the peakedness of the heating beam fueling profile shape. Ion energy confinement and neutron production are relatively insensitive to other plasma parameters compared to the beam fueling peakedness parameter and the heating beam power when considering plasmas that are stable to magnetohydrodynamic modes. However, the stored energy of the electrons is independent of the beam fueling peakedness. The implication of the scalings based on this parameter is related to theoretical transport models such as radial electric field shear and Ion Temperature Gradient marginality models. Similar physics interpretation is provided for beam heated discharges on other major tokamaks

(E)-4-Phenyl­butan-2-one oxime

In the title compound, C10H13NO, the C—C—C—C torsion angle formed between the benzene ring and the butan-2-one oxime unit is 73.7 (2)°, with the latter lying above the plane through the benzene ring. In the crystal, inter­molecular O—H⋯N hydrogen bonds link pairs of mol­ecules into dimers, forming R 2 2(6) ring motifs which are stacked along the a axis

Modification Of The Electron Energy Distribution Function During Lithium Experiments On The National Spherical Torus Experiment

The National Spherical Torus Experiment (NSTX) has recently studied the use of a liquid lithium divertor (LLD). Divertor Langmuir probes have also been installed for making measurements of the local plasma conditions. A non-local probe interpretation method is used to supplement the classical probe interpretation and obtain measurements of the electron energy distribution function (EEDF) which show the occurrence of a hot-electron component. Analysis is made of two discharges within a sequence that exhibited changes in plasma fueling efficiency. It is found that the local electron temperature increases and that this increase is most strongly correlated with the energy contained within the hot-electron population. Preliminary interpretative modeling indicates that kinetic effects are likely in the NSTX

Quaternionic Salkowski Curves and Quaternionic Similar Curves

In this paper, we give the definitions and characterizations of quaternionic Salkowski, quaternionic anti-Salkowski and quaternionic similar curves in the Euclidean spaces E^3 and E^4. We obtain relationships between these curves and some special quaternionic curves such as quaternionic slant helices and quaternionic B2-slant helices.Comment: 17 page

Formation mechanism of a nano ring of bismuth cations and mono-lacunary Keggin-type phosphomolybdate

A new hetero-bimetallic polyoxometalate (POM) nano ring was synthesized in a one-pot procedure. The structure consists of tetrameric units containing four bismuth-substituted monolacunary Keggin anions including distorted [BiO8] cubes. The nano ring is formed via self -assembly from metal precursors in aqueous acidic medium. The compound (NH4)16[(BiPMo11O39)4]×22H2O; (P4Bi4Mo44) was characterized by single-crystal X-ray diffraction, extended X-ray absorption fine structure spectroscopy (EXAFS), Raman spectroscopy, matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF), and thermogravimetry/differential scanning calorimetry (TG-DSC-MS). The formation of the nano ring in solution was studied by time-resolved in situ small- and wide-angle X-ray scattering (SAXS/WAXS) and in situ EXAFS measurements at the Mo-K and the Bi-L3 edge indicating a two-step process consisting of condensation of Mo-anions and formation of Bi-Mo-units followed by a rapid self-assembly to yield the final tetrameric ring structure

Influence of topography on tide propagation and amplification in semi-enclosed basins

An idealized model for tide propagation and amplification in semi-enclosed rectangular basins is presented, accounting for depth differences by a combination of longitudinal and lateral topographic steps. The basin geometry is formed by several adjacent compartments of identical width, each having either a uniform depth or two depths separated by a transverse topographic step. The problem is forced by an incoming Kelvin wave at the open end, while allowing waves to radiate outward. The solution in each compartment is written as the superposition of (semi)-analytical wave solutions in an infinite channel, individually satisfying the depth-averaged linear shallow water equations on the f plane, including bottom friction. A collocation technique is employed to satisfy continuity of elevation and flux across the longitudinal topographic steps between the compartments. The model results show that the tidal wave in shallow parts displays slower propagation, enhanced dissipation and amplified amplitudes. This reveals a resonance mechanism, occurring when\ud the length of the shallow end is roughly an odd multiple of the quarter Kelvin wavelength. Alternatively, for sufficiently wide basins, also Poincaré waves may become resonant. A transverse step implies different wavelengths of the incoming and reflected Kelvin wave, leading to increased amplitudes in shallow regions and a shift of amphidromic points in the direction of the deeper part. Including the shallow parts near the basin’s closed end (thus capturing the Kelvin resonance mechanism) is essential to reproduce semi-diurnal and diurnal\ud tide observations in the Gulf of California, the Adriatic Sea and the Persian Gulf