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A research activity in the Institute for Plasma Science and Technology of National Research Council (ISTP-CNR, Italy, former IFP-CNR) and in L.T. Calcoli (LTC, Italy) is aimed at the design and construction of calorimetric loads for absorption and measurement of high power millimeter-waves in the electron cyclotron frequency range. Recently, two CW 170 GHz loads, one for the European ITER gyrotron test facility and the other for the FALCON test- bed, have been installed at the Swiss Plasma Center (SPC, Switzerland). One short pulse (2 s) load for 1 MW, designed and optimised to operate at two different frequencies (84 GHz and 126 GHz), was provided for testing and conditioning two new dual-frequency gyrotrons for the Tokamak à Configuration Variable (TCV, Switzerland). Two additional CW loads, designed for absorbing powers higher than 1 MW, have been delivered to the National Institutes for Quantum and Radiological Science and Technology (QST, Japan) and exploited for the acceptance tests and the conditioning of the prototype of the Japanese ITER gyrotron. The present status and the most recent experimental results achieved in the framework of this development activity are reported in the paper.

Proceedings of the International Conference on Numerical Analysis and Applied Mathematics 2014 (ICNAAM-2014), 22–28 September 2014 Location: Rhodes, Greece ISBN 978-0-7354-1287-3 In the present paper the Flamelet-Generated Manifold (FGM) chemistry reduction method is implemented and extended for the inclusion of all the features that are typically observed in stationary gas-turbine combustion. These consist of stratification effects, heat loss and turbulence. The latter is included by coupling FGM with the Reynolds Averaged Navier Stokes(RANS)model. Three control variables are included for the chemistry representation: the reaction evolution is described by the reaction progress variable, the heat loss is described by the enthalpy and the stratification effect is expressed by the mixture fraction. The interaction between chemistry and turbulence is considered through a presumed probability density function (PDF) approach, which is considered for progress variable and mixture fraction. This results in two extra control variables: progress variable variance and mixture fraction variance. The resulting manifold is five-dimensional, in which the dimensions are progress variable, enthalpy, mixture fraction, progress variable variance and mixture fraction variance. In addition, a highly turbulent and swirling flame in a gas turbine model combustor is computed, in order to test the 5-D FGM implementation. The use of FGM as a combustionmodel shows that combustion features at gas turbine conditions can be satisfactorily reproduced with a reasonable computational effort. The implemented combustionmodel retains most of the physical accuracy of a detailed simulation while drastically reducing its computational time, paving the way for new developments of alternative fuel usage in a cleaner and more efficient combustion. In the present paper the Flamelet-Generated Manifold (FGM) chemistry reduction method is implemented and extended for the inclusion of all the features that are typically observed in stationary gas-turbine combustion. These consist of stratification effects, heat loss and turbulence. The latter is included by coupling FGM with the Reynolds Averaged Navier Stokes(RANS)model. Three control variables are included for the chemistry representation: the reaction evolution is described by the reaction progress variable, the heat loss is described by the enthalpy and the stratification effect is expressed by the mixture fraction. The interaction between chemistry and turbulence is considered through a presumed probability density function (PDF) approach, which is considered for progress variable and mixture fraction. This results in two extra control variables: progress variable variance and mixture fraction variance. The resulting manifold is five-dimensional, in which the dimensions are progress variable, enthalpy, mixture fraction, progress variable variance and mixture fraction variance. In addition, a highly turbulent and swirling flame in a gas turbine model combustor is computed, in order to test the 5-D FGM implementation. The use of FGM as a combustionmodel shows that combustion features at gas turbine conditions can be satisfactorily reproduced with a reasonable computational effort. The implemented combustionmodel retains most of the physical accuracy of a detailed simulation while drastically reducing its computational time, paving the way for new developments of alternative fuel usage in a cleaner and more efficient combustion.

In past earthquake disasters, numerous building structure piles were damaged by soil liquefaction occurring during the earthquake. Damage to these piles, because they are underground, is difficult to find. The authors aim to develop a monitoring method of pile damage based on superstructure dynamic response. This paper investigated the relationship between the damage of large cross section cementitious piles and the dynamic response of the super structure using a centrifuge test apparatus. A dynamic specimen used simple cross section pile models consisting of aluminum rod and mortar, a saturated soil (Toyoura sand) of a relative density of 40% and a super structure model of a natural period of 0.63sec. In the shaking table test under a 50G field (length scale of 1/50), excitation was a total of 3 motions scaled from the Rinkai wave at different amplitudes. The maximum acceleration of each of the excitations was 602gal, 336gal and 299gal. The centrifuge test demonstrated the liquefaction of saturated soil and the failure behavior of piles. In the test result, the damage of piles affected the predominant period of acceleration response spectrum on the footing of the superstructure.In past earthquake disasters, numerous building structure piles were damaged by soil liquefaction occurring during the earthquake. Damage to these piles, because they are underground, is difficult to find. The authors aim to develop a monitoring method of pile damage based on superstructure dynamic response. This paper investigated the relationship between the damage of large cross section cementitious piles and the dynamic response of the super structure using a centrifuge test apparatus. A dynamic specimen used simple cross section pile models consisting of aluminum rod and mortar, a saturated soil (Toyoura sand) of a relative density of 40% and a super structure model of a natural period of 0.63sec. In the shaking table test under a 50G field (length scale of 1/50), excitation was a total of 3 motions scaled from the Rinkai wave at different amplitudes. The maximum acceleration of each of the excitations was 602gal, 336gal and 299gal. The centrifuge test demonstrated the liquefaction of saturated soil ...

The study presents a 2D fluid plasma model of a gliding arc discharge for dissociation of CO2 which allows its subsequent conversion into value-added chemicals. The model is based on the balance equations of charged and neutral particles, the electron energy balance equation, the gas thermal balance equation and the current continuity equation. By choosing the modeling domain to be the plane perpendicular to the arc current, the numerical calculations are significantly simplified. Thus, the model allows us to explore the influence of the gas instabilities (turbulences) on the energy efficiency of CO2 conversion. This paper presents results for plasma parameters at different values of the effective turbulent thermal conductivity leading to enhanced energy transport.

This paper concerns the numerical solution of the BlackScholes PDE with a Neumann boundary condition on the right boundary. We consider finite difference schemes for the semi-discretization, which leads to a system of ODEs with corresponding matrix M. In this paper stability bounds for exp(tM) (t ≥ 0) are proved. A scaled version of the Euclidean norm, denoted by ‖ ⋅ ‖H is considered. The advection and diffusion term of the PDE are analyzed separately. It turns out that the Neumann boundary condition leads to a growth of ‖exp(tM)‖H with the number of grid points m for the pure advection problem.

The significant drop of the storage modulus under uniaxial deformation (Payne effect) restrains the performance of the elastomer-based composites and the development of possible new applications. In this paper molecular-dynamics (MD) computer simulations using LAMMPS MD package have been performed to study the mechanical properties of a coarse-grained model of this family of nanocomposite materials. Our goal is to provide simulational insights into the viscoelastic properties of filled elastomers, and try to connect the macroscopic mechanics with composite microstructure, the strength of the polymer-filler interactions and the polymer mobility at different scales. To this end we simulate random copolymer films capped between two infinite solid (filler aggregate) walls. We systematically vary the strength of the polymer-substrate adhesion interactions, degree of polymer confinement (film thickness), polymer crosslinking density, and study their influence on the equilibrium and non-equilibrium structure, segmental dynamics, and the mechanical properties of the simulated systems. The glass-transition temperature increases once the mesh size became smaller than the chain radius of gyration; otherwise it remained invariant to mesh-size variations. This increase in the glass-transition temperature was accompanied by a monotonic slowing-down of segmental dynamics on all studied length scales. This observation is attributed to the correspondingly decreased width of the bulk density layer that was obtained in films whose thickness was larger than the end-to-end distance of the bulk polymer chains. To test this hypothesis additional simulations were performed in which the crystalline walls were replaced with amorphous or rough walls.

This paper concerns the efficient numerical solution of the time-dependent, three-dimensional Heston-Hull-White PDE for the fair prices of European call options. The numerical solution method described in this paper consists of a finite difference discretization on non-uniform spatial grids followed by an Alternating Direction Implicit scheme for the time discretization and extends the method recently proved effective by In't Hout & Foulon (2010) for the simpler, two-dimensional Heston PDE.

Air-coupled ultrasound testing is known as one of attractive non-contact ultrasonic NDE methods. However, the sensitivity of the air-coupled method greatly depends on the positioning of transducers, because the difference of acoustic impedance between air and solid is very large. In order to use this method for quantitative detection and evaluation of material flaws, it is necessary to simulate ultrasonic wave propagation and scattering in a solid. For a coupling problem between two media, in which ultrasonic waves travel at greatly different velocities, it is difficult to obtain stable solutions by means of a conventional time-domain boundary element method (BEM). A convolution quadrature time-domain fast multipole BEM (CQ-FMBEM) has been developed for the simulation of ultrasonic wave propagation and scattering in a solid. In the CQ-FMBEM, a convolution quadrature method (CQM) is introduced to make BEM solutions stable by evaluating a convolution integral in a very accurate numerical manner, while a fast multipole method (FMM) is used to accelerate the computations effectively for large scale problems. In this paper, 2-D and 3-D scattering problems of ultrasonic waves due to defects near an interface between air and solid are solved in order to simulate ultrasound scattering phenomena.

In this study, two-phase immiscible polymer blend with selective radiation heating by infrared laser is studied numerically. The phase-field model of a non-isothermal flow, which accounts for laser induced temperature field, two-phase flow with interfacial tension and Marangoni effect, was developed. This model was used to simulate a droplet deforming in shear flow with various shear rate, droplet size and laser irradiation power. Based on the simulation results the effect of the selective radiation heating by infrared laser to the droplet deformation, the break-up situation and the micro-structure of the polymer blend was discussed. The paper concludes with suggestions for future research and potential applications.

This paper presents an inverse modeling approach to estimate mechanical properties of asphalt concrete (i.e. Young's modulus E, Poisson ratio v and damping coefficients). Modal analysis was performed on an asphalt slab using a shaker to excite the specimen and an optical measurement system (a Scanning Laser Doppler Vibrometer or SLDV) to measure the velocity of a measurement grid on the surface of the slab. The SLDV has the ability to measure the vibration pattern of an object with high accuracy, short testing time and without making any contact. The measured data were used as inputs for a frequency domain model parameter estimation method (the Polymax estimator). Meanwhile, natural frequencies and damping ratios of the system were calculated using a Finite Element Modeling (FEM) method. Then, the Modal Assurance Criterion (MAC) was used to pair the mode shapes of the structure determined by measurements and estimated by FEM. By changing the inputs of the FEM analysis (E, v and damping coefficients of the material) iteratively and minimizing the discrepancy between paired natural frequencies and damping ratios of the system estimated using the Polymax estimator and calculated by FEM, the Young's modulus, Poisson ratio and damping coefficients of the asphalt slab were estimated.

E906/SeaQuest at FNAL is a fixed‐target experiment to measure the Drell‐Yan process with a 120‐GeV proton beam and liquid‐hydrogen/deuterium targets. The main purpose of this experiment is to precisely measure the asymmetry of ū and d distributions in the proton at an xBj range from 0.25 to 0.45. E906/SeaQuest is about to start a beam experiment. The physics capabilities and the current status of the experiment is reported in this paper.

This paper considers a mathematical model of infectious disease of SIS type. We will analyze the problem of minimizing the cost of diseases trough medical treatment. Mathematical modeling of this process leads to an optimal control problem with a finite horizon. The necessary conditions for optimality are given. Using the optimality conditions we prove the existence, uniqueness and stability of the steady state for a differential equations system.

We proposed a method for object tracking employing a particle filter based on color feature method. A histogram‐based framework is used to describe the features. Histograms are useful because they have property that they allow changes in the object appearance while the histograms remain the same. Particle filtering is used because it is very robust for non‐linear and non‐Gaussian dynamic state estimation problems and performs well when clutter and occlusions are present on the image. Bhattacharyya distance is used to weight the samples in the particle filter by comparing each sample’s histogram with a specified target model and it makes the measurement matching and sample’s weight updating more reasonable. The method is capable to track successfully the moving object in different outdoor environment with and without initial positions information, and also, capable to track the moving object in the presence of occlusion using an appearance condition. In this paper, we propose a color features‐based method for object tracking based on the particle filters. The experimental results and data show the feasibility and the effectiveness of our method., International Conference on Power Control and Optimization, 1-3, June 2009, Bali, Indonesia

Laser-driven, in-tube accelerator is a laser propulsion device in which the impulse performance is enhanced by the confinement of the compressible fluid. This paper describes the conceptual origin and state of the art of this technology.

Biosensors research combines molecular-level with system-level challenges. The molecular challenge is to rapidly and reliably detect very low concentrations of molecules in a complex biological sample. The system challenge is to find principles that enable the integration of a series of process steps in a disposable cartridge. This paper describes how both aspects can be served by the actuation and detection of magnetic particles, illustrated by the example of immunoassay biosensing.

42ND ANNUAL REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION: Incorporating the 6th European-American Workshop on Reliability of NDE, 26–31 July 2015, Minneapolis, Minnesota, Takahiro Hayashi and Daisuke Inoue, "Guided wave propagation in metallic and resin plates loaded with water on single surface", AIP Conference Proceedings 1706, 030003 (2016) https://doi.org/10.1063/1.4940475, Our previous papers reported dispersion curves for leaky Lamb waves in a water-loaded plate and wave structures for several typical modes including quasi-Scholte waves [1,2]. The calculations were carried out with a semi-analytical finite element (SAFE) method developed for leaky Lamb waves. This study presents SAFE calculations for transient guided waves including time-domain waveforms and animations of wave propagation in metallic and resin water-loaded plates. The results show that non-dispersive and non-attenuated waves propagating along the interface between the fluid and the plate are expected for effective non-destructive evaluation of such fluid-loaded plates as storage tanks and transportation pipes. We calculated transient waves in both steel and polyvinyl chloride (PVC) plates loaded with water on a single side and input dynamic loading from a point source on the other water-free surface as typical examples of metallic and resin plates. For a steel plate, there exists a non-dispersive and non-attenuated mode, called the quasi-Scholte wave, having an almost identical phase velocity to that of water. The quasi-Scholte wave has superior generation efficiency in the low frequency range due to its broad energy distribution across the plate, whereas it is localized near the plate-water interface at higher frequencies. This means that it has superior detectability of inner defects. For a PVC plate, plural non-attenuated modes exist. One of the non-attenuated modes similar to the A0 mode of the Lamb wave in the form of a group velocity dispersion curve is promising for the non-destructive evaluation of the PVC plate because it provides prominent characteristics of generation efficiency and low dispersion.

The most-suited instrument for high-accuracy mass and therefore for high-accuracy Q-value determinations is the Penning trap. However, the most-advanced type of Penning trap mass spectrometer up to date needs a drastic improvement in order to contribute from a Q-value measurement to the mass determination of the electron antineutrino at the level of 10−12 as pursued by the international MARE collaboration measuring the end-point of the decay 187Re to 187Os. In this contribution, a novel device, called quantum sensor, is proposed to measure the mass of a single ion with ultimate accuracy and unprecedented sensitivity while it is stored and cooled in a trap. The quantum sensor is made of a reference ion suspended in vacuum by the electric and magnetic field of a Penning trap, and laser cooled to very low temperatures. By wiring this ion with the ion of interest, the mass of the later can be determined from its cyclotron frequency using the fluorescence of the reference ion. This paper will present the application of the quantum sensor in the determination of the mass of the neutrino.

WP10 is one of the working packages of the HiPER project and it has the goal of addressing, in a systematic and programmatic way, some of the key experimental uncertainties on the way towards fast ignition (and shock ignition) in a perspective of risk reduction, so to contribute to the definition of the basic characteristics of the HiPER project. The paper describes the key points contained in the short term HiPER experimental road map, as well as the results of two first experiments performed in "HiPER dedicated time slots" in European Laser Facilities. © 2010 American Institute of Physics.

This paper deals with stability in the numerical solution of general one-dimensional partial differential equations with variable coefficients. We will generalize stability results for central finite difference schemes on non-uniform grids that were obtained by In't Hout & Volders (2009) for the Black-Scholes equation. Subsequently we will apply our stability results to the CEV model.

HTS leads are increasingly used on superconducting magnets. In most cases the magnet leads are shielded from the magnetic field by iron or the magnet is actively shielded, so that the stray field at HTS leads is low. There are magnets where the HTS leads must be located in a magnetic field. The two general types of HTS leads that are commercially available are either leads fabricated from bulk HTS materials or leads fabricated from oriented HTS materials that have one or two planes of favorable current density. This paper will discuss how two types of leads are affected by magnetic field. The warm end temperature of the HTS lead is a key lead performance factor. © 2008 American Institute of Physics.

The first successful experimental studies of microwave radiation from a co-axial Free-Electron Maser (FEM) based on two-dimensional (2D) distributed feedback have been recently conducted. This paper contains a description of the experimental set-up and the results obtained. The high-power pulsed power supply and high-current accelerator (HCA) developed and used to drive the FEM are discussed. The results of the experimental study of the FEM operating in the Ka frequency band are presented and compared with theoretical predictions. © 2005 American Institute of Physics.