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This paper presents a design verification for a small Stand-Alone Photovoltaic (SAPV) system under Malaysian tropical climate. The two design methods applied in this study were Mathematical Sizing (MS) model, which claimed to be one of the best sizing methods under Malaysian tropical climate and PVSYST commercial software. The comparison on the design results demonstrated that MS and PVSYST sizing methods have similarities but also differences. The study verified that both methods showed that increasing the system voltage, will reduce the required battery capacity. Significantly, the PVSYST software was found to oversize the battery bank and PV modules capacity required to meet the total energy required from load profile assessment. The differences encountered between the MS and PVSYST software were conceivably due to the different design parameters setting namely the minimum PV module temperature threshold, ambient temperature and battery parameters involved in the design calculation. This study has highlighted several technical understandings on designing SAPV system in both design methods, that can facilitate the PV system designers to evaluate the assumptions and mathematical models applied specifically in each sizing models. [ABSTRACT FROM AUTHOR]

In this paper, the sparse variable selection problem is considered for the Gaussian linear models. Varying forms of nonconvex penalties have been investigated for solving sparse variable selection problem with a specific interest in finding a solution under different forms of convex algorithmic structure. Specifically, this study investigates the solution paths of three different algorithms that utilized the coordinate-wise descent optimization technique. The three algorithms considered are the Least Absolute Selection Operator (LASSO), Minimax Concave Penalty (MCP or MC+) and the SparseNet. The predictive performances of the algorithms were studied for comparison using a Monte-Carlo simulation of several linear regression modelling scenarios. [ABSTRACT FROM AUTHOR]

This paper presents the study on deformability analysis of sheet metal forming by using finite element methods (FEM). The paper particularly focuses on application of dynamic explicit and static implicit approaches to simulate metal forming of rectangular cups where different material models and contact conditions with friction are involved. Comparative studies of the results on formability of the forming process using the two approaches are presented. The simulated results are verified using results from experimental study of the deformation on the same material. Further, a comparison between a quadratic Hill anisotropic yield criterion and von Mises yield criterion with isotropic hardening has been presented. The results confirm that the dynamic explicit procedure is more efficient in simulating sheet metal forming processes. The study shows also that the finite element analysis undoubtedly gives good approximate numerical results to real processes when the material and friction anisotropy are considered. [ABSTRACT FROM AUTHOR]

In this paper, we concern at situations where we have to compare selected parameters from particular nonlinear models. A motivational examples of previously modelled data are given at the beginning. When comparing parameters from two models, it is possible to combine them into one model. But for three and more models, it is necessary to correct significance level at advance. Two approaches to solving this problem are stated, so-called Šidák correction and Bonferroni method. Results of these methods as well as results coming from the situation where significance level correction is omitted are compared based on simulated data. [ABSTRACT FROM AUTHOR]

Modeling and simulation research on automobile ABS bench detection is conducted in this paper. First, the vehicle model, wheel model, braking force model, and tire-road model on the bench are established according to the ABS bench detection scheme. Then, the Matlab/Simulink simulation model of a single wheel vehicle is built through combining the sub-models described above. Finally, simulation experiments on a variety of simulated road conditions are carried out. And the comparative analysis between the ABS bench detection and ABS road experiments is accomplished. The contrast results show that the simulation curves of bench detection and those of road experiment have high similarity, which verified the correctness and feasibility of the proposed bench detection scheme. [ABSTRACT FROM AUTHOR]

Simulation of Eddy Current Testing (ECT) signals due to real cracks constitutes a matter of interest in many industrial fields. Such complex flaws can be modeled as a succession of narrow crack with canonical shapes (i.e. slot, elliptical, semi-elliptical, etc.) having arbitrary positions and orientations. This paper present a semi-analytical model dedicated to the simulation of ECT inspections of stratified planar structures, affected by narrow crack. Validation of the developments, carried out with experimental data or by comparison with other numerical results, are then discussed. [ABSTRACT FROM AUTHOR]

The paper studies the high altitude effects to the future hypersonic/suborbital re-entry vehicle SpaceLiner developed in the framework of EC-funded FAST20XX project. Bridging functions have been developed and validated by means of DSMC calculations. The effects of rarefaction on global longitudinal aerodynamics of SpaceLiner in the range of altitude 65÷85 km have been pointed out by comparing to the aerodatabase in continuum regime conditions. DSMC computation has been done in the higher SpaceLiner altitude point confirming the bridging function results and providing heat transfer estimations. [ABSTRACT FROM AUTHOR]

This paper proposes a high absorption coefficient micro-perforated panel (MPP) imitating owl skin structure for acoustic noise reduction. Compared to the traditional micro-perforated panel, this device has two unique characteristics-simulating the owl skin structure, its radius of perforated apertures even can be as small as 55μ, and its material is silicon and fabricated by micro-electrical mechanical system (MEMS) technology; So that its absorption coefficients of acoustic noise for normal incidence sound wave whose frequencies arrange from 1.5 kHz to 6.0 kHz are all above 0.8 which is the owl's hunts sensitivity frequency band. Double leaf MPP fabricated by MEMS technology is an absolutely bionic success in functional-imitation. [ABSTRACT FROM AUTHOR]

Plasma doping (PLAD) shows very different impurity profiles compared to the conventional beam-line-based ion implantations due to its non-mass separation property and plasma environment. There is no simulation for PLAD process so far due to a lack of a dopant profile model. Several factors determine impurity profiles of PLAD process. The most significant factors are: plasma chemistry and deposition/etching characteristics of multi-ion species plasmas. In this paper, we present plasma chemistry and deposition/etching characteristics of PLAD processes versus co-gas dilutions. Four dopant plasmas including B2H6, BF3, AsH3, and PH3, and two non-dopant plasmas including CH4 and GeH4 are studied and demonstrated. [ABSTRACT FROM AUTHOR]

In a recently-published series of papers we studied the general problem of matching large PV systems of various kinds to the electricity grid. In those studies CPV systems were simulated via an artificial ansatz in which they were treated as 2-axis flat-panel PV systems whose light sensitivity is only to the direct normal component (DNI) of solar irradiance. The present study replaces this ansatz with an experimentally validated model of a real CPV system. We compare a genuine 2-axis high-concentration CPV system with a static flat-panel PV system from the standpoint of matching both system types to the Israeli electricity grid. [ABSTRACT FROM AUTHOR]

Generalized hydrodynamic equations (GHE) proposed by Alexeev (1994), have been explored for simulations of viscous flows for a wide range of problems and flow parameters, including high Reynolds numbers flows with thin boundary layers. These GHE is not a turbulence model, and no additional equations are introduced. Spacial fluctuations (small flow scales) can be successfully captured with GHE, and the derived small scale of turbulent flow compares well with observed one in the experiments by Koseff and Street (1984). In this paper, we review numerical solutions using GHE for several viscous flow problems and compare numerical results with experimental data for the cases we considered in the range of Reynolds number from Re = 10-6, to 3200, and to 1,000,000. The method is reviewed and numerical solutions are compared with the experimental data for a 3D driven cavity flow at Re = 3200 and 10,000, 2D backward facing step flow at Re = 44,000, 2D channel flow at Re number up to 106; and a 3D thermal convection in a cylinder at Ra = 1000 to 150,000. Comparison with the analytical asymptotic solution is provided for a thermal convection, in the electrically conducting fluid suppressed by a strong magnetic field at Hartman numbers Ha up to 20,000 (Re = 10-5). In all the cases considered, GHE results compare favorably with experimental data. 2D and 3D Naver-Stokes solutions and k - [variant_greek_epsilon] model solutions are also provided, and they are outperformed by GHE results. [ABSTRACT FROM AUTHOR]

The French Institute for Radioprotection and Nuclear Safety (IRSN) in partnership with CEA, has started in 2009 a program over several years for the validation of CIVA RX module. The aim of this paper is to present preliminary results of CIVA RX tools validation. The study consists in a cross comparison between experimental and simulation results. These have been carried out on different objects (step wedge, dissimilar metal weld mock up, IQI, notches) with different sources (Co60 and 450 kV X-ray tube) and radiographic film. Simulation and experimental data are compared in term of optical density, IQI perceptivity and flaws detectability. This study shows a good agreement between experiment and simulation. [ABSTRACT FROM AUTHOR]

The numerical simulation of Localised-Incremental Forging (LIF) is a challenging task. The analysis of LIF operations is often difficult, especially when several strokes are necessary to obtain the final shape of the part. The use of FE models is mandatory because incremental operations throughout a workpiece are difficult to analyse with conventional analytical methods. It is known that, in general, implicit FE models give more robust results than explicit FE models; however, with the former methodology there are several problems that must be faced. With the main goal to extend the analysis capability of LIF operations, some explicit FE models are developed in this paper and results are compared to those obtained by implicit methodology. It can be concluded that taking into account these guidelines, the developed models could be further used in the analysis of multi-strokes LIF operations, where more complicated trajectories will be required. [ABSTRACT FROM AUTHOR]

This paper compares methods used for integration of cooling system in the press hardening simulation. For this purpose an experimental tool was developed and constructed. This tool makes it possible to compare and validate different simulation methods applicable for cooling systems and resolves the question of their importance. The simplified shape of the tool has been chosen to break down the problem to less numerous parameters limited to thermodynamics and fluid dynamics. Such a simplified problem can better address the parameters like heat transfer coefficient in channels depending on channel geometry and flow speed of cooling water, and can easily relate them to the reality. A temperature distribution on the tool surface for different geometries of channels is presented under chosen flow speeds of cooling medium and heating power of integrated heating elements and compared to the results from both FEM and CFD simulation methods. Resultant heat transfer coefficients for different flow speeds of water and cooling channels geometries will be calculated through the inverse calculation, compared to the analytical calculation. The conclusion should reveal whether it is better, for a given geometry, to use a constant analytically calculated heat transfer coefficient, constant coefficient from the inverse calculation, or variable heat transfer coefficient from CFD simulation. [ABSTRACT FROM AUTHOR]

Structure reliability guaranty requires prior evaluation of non destructive testing methods. The concept of Probability of Detection (POD) is generally used to quantitatively assess performances and reliability of testing operations. Such probabilistic approaches take into account the uncertainties that appear during inspections and that are responsible for the output variability. POD curve determination is based on costly and time consuming experimental campaigns. Increasing demand of NDT configurations requiring POD evaluation makes cost reduction of POD campaigns a major issue. A new trend is to apply simulation in the context of probabilistic approaches in order to replace some of the experimental data required to determine the POD with simulation results. This paper presents results of simulation based POD curves of a high frequency eddy current inspection procedure obtained with the new POD module of CIVA. The methodology used for describing uncertainties on the input simulation parameters is described and comparisons with experimental results are presented and discussed. [ABSTRACT FROM AUTHOR]

In this paper, a method for obtaining a three dimensional crack model from a radiographic image is discussed. A genetic algorithm aiming at close simulation of crack's shape is presented. Results obtained with genetic algorithm are compared to those achieved in authors' previous work. The described algorithm has been tested on both simulated and real-life cracks. [ABSTRACT FROM AUTHOR]

In this paper, a novel speckle reduction method is proposed for ultrasound images. This denoising method is designed to preserve both the edges and structural details of the image. Speckle noise is suppressed, without smearing the edges, by extending the smoothness of the image in the wavelet-based Hölder spaces. A comparison of smoothing speckles with the other well known methods is provided via the size of Besov norm. We validate the proposed method using synthetic data and simulated ultrasound images. Experiments demonstrate the performance improvement of the proposed method over other state-of-the-art methods in terms of image quality and edge preservation indices. [ABSTRACT FROM AUTHOR]

In this work, we develop a new species weighting scheme to reduce the computational effort associated with the study of freely expanding homogeneous condensation flows. The present work is an extension of our previous work [Kumar et al., AIAA Paper 2010-818 (2010)], in which, we developed CO2 condensation models in the statistical BGK framework to simulate the experimental data [Ramos et al., Phys. Rev. A72, 3204 (2005)] for stagnation pressures up to 5 bar. The present work is aimed at the development of a numerically efficient numerical scheme that will extend the range of applicability of the present condensation models to the more challenging flow regimes of higher stagnation pressures. The accuracy and efficiency of the new species weighting factor method is compared with simulations performed without weighting factors. Numerical results are found to be in agreement, with the new approach shown to significantly reduce the computational effort. [ABSTRACT FROM AUTHOR]

This paper analyzes compressible gaseous slip flow through a three-dimensional straight uniform rectangular microchannel, and reports a set of asymptotic solutions. By comparing the magnitudes of different forces in the compressible gas flow, we obtain a proper criteria to estimate the Reynolds and Mach numbers at the channel exit. We select two sets of Mach and Reynolds numbers and obtain asymptotic analytical solutions of velocities and pressure distributions; first order velocity slip and non-slip boundary conditions are examined. The analytical results of pressure and velocities are compared with numerical simulation results of direct simulation Monte Carlo method and the results that are available in the literature. [ABSTRACT FROM AUTHOR]

For phase estimation in digital holographic interferometry, a high-order instantaneous moments (HIM) based method was recently developed which relies on piecewise polynomial approximation of phase and subsequent evaluation of the polynomial coefficients using the HIM operator. A crucial step in the method is mapping the polynomial coefficient estimation to single-tone frequency determination for which various techniques exist. The paper presents a comparative analysis of the performance of the HIM operator based method in using different single-tone frequency estimation techniques for phase estimation. The analysis is supplemented by simulation results. [ABSTRACT FROM AUTHOR]