Toward a stochastically robust normalized impact factor against fraud and scams

Scientometrics - In this paper, we model the variation of the bibliometric measure differences across academic fields in order to quantify the sources of these discrepancies. Since the bibliometric...     

Dielectric properties of honeydew melons and correlation with quality.

Dielectric properties of three honeydew melon cultivars, grown and harvested to provide a range of maturities, were measured with an open-ended coaxial-line probe and impedance analyzer over the frequency range from 10 MHz to 1.8 GHz. Probe measurements were made on the external surface of the melons and also on tissue samples from the edible internal tissue. Moisture content and soluble solids content (SSC) were measured for internal tissue samples, and SSC (sweetness) was used as the quality factor for correlation with the dielectric properties. Individual dielectric constant and loss factor correlations with SSC were low, but a high correlation was obtained between the SSC and permittivity from a complex-plane plot of dielectric constant and loss factor, each divided by SSC, for both the external surface and internal tissue measurements. However, SSC prediction from the dielectric properties by these relationships was not as high as expected. Permittivity data (dielectric constant and loss factor) for the melons are presented graphically to show their relationships with frequency for external surface and internal tissue measurements. A dielectric relaxation for the external surface measurements, which is attributable to bound water and Maxwell-Wagner relaxations, is also illustrated. Coefficients of determination for complex-plane plots, moisture content and SSC relationship, and penetration depth are also shown graphically. Further studies are needed for determining the practicality of sensing melon quality from the dielectric properties.     

Surrogate models for uncertainty analysis of micro-actuator

Microsystem Technologies - Intelligent materials such as shape memory alloy have attracted the attention of scientists to innovate applications in micromachining technology. It is worth mentioning...     

Simultaneous shape,topology, and homogenized properties optimization

In this brief note, we present an approach that combines the three classical techniques in structural optimization, i.e. the boundary variation and the topological and the homogenization methods. As a first test of this method, we apply it to the compliance opti-mization in .     

Modelling of Failure of Woven Composites. Part 1: Nomenclature Defining the Interzone Concept

The failure of woven composites has been examined. This study is presented in two parts:

• Modelling of failure of woven composites. Part 1: nomenclature defining the interzone concept;
• Modelling of failure of woven composites. Part 2: experimental and numerical justification of the interzone concept.

In the first part, the concepts of the interzone and the geometry of an interzone have been defined in a general way for a large panel of woven composites. In the second part, it has been shown that the failure of woven composites is well described by using the interzone concept. The load transfer between intact interzones and broken interzones has been evaluated for two types of loadings (tensile loading and loading in bending). The analysis of these load transfers explains why in the case of a tensile loading the failure is of a sudden-death type whereas in the case of bending loading the failure is progressive. The concept of failure of an interzone has been also defined.     

Traps centers impact on Silicon nanocrystal memories given by Random Telegraph Signal and low frequency noise

This work reports on a comprehensive process of trapping centers in Silicon nanocrystal (nc-Si) memories devices. The trap centers have been studied using Random Telegraph Signal (RTS) and Low Frequency (LF) techniques. The study of the traps which are responsible for RTS noise in non-volatile memories (NVM) devices as a function of gate voltage and temperature, offers the opportunity of studying the trapping/detrapping behaviour of a single interface trap center. The RTS parameters of the devices having random discrete fluctuations in the drain current get more information about trap energy level and spatial localization from the SiO₂/Si interface. The impact of trap centers has been also investigated showing the significant noise between memories and references devices. Furthermore, it has convincingly been shown that this discrete switching of the drain current between a high and a low state is the basic feature responsible for l/f^γ flicker noise in MOSFETs transistors.     

Incorporation of the Goudsmit–Saunderson electron transport theory in the Geant4 Monte Carlo code

The present work describes the implementation of the multiple scattering formalism for charged particle transport based on the Goudsmit–Saunderson angular distribution and satisfying the Lewis spatial displacement theories. Furthermore, the most realistic total cross sections and transport cross sections for single elastic scattering of electrons and positrons by neutral atoms were carried out using the ELSEPA code. The extended model has been incorporated in the Geant4 Monte Carlo code system (currently used in many fields of application for transport of particles and covering a large range of energies from 0.1 keV to 100 TeV). Additionally, techniques are developed that allow the distributions to be scaled to account for energy loss. This new representation allows on-the-fly sampling of Goudsmit–Saunderson angular distributions in a screened Rutherford approximation suitable for Class II condensed history Monte Carlo codes. The reliability of the model is demonstrated through a comparison of simulation results with experimental data. Good agreement is found for electrons with kinetic energies down to a few keV.     

Photocatalytic activity of Cr-doped TiO2 nanoparticles deposited on porous multicrystalline silicon films

This work deals with the deposition of Cr-doped TiO₂ thin films on porous silicon (PS) prepared from electrochemical anodization of multicrystalline (mc-Si) Si wafers. The effect of Cr doping on the properties of the TiO₂-Cr/PS/Si samples has been investigated by means of X-ray diffraction (XRD), atomic force microcopy (AFM), photoluminescence, lifetime, and laser beam-induced current (LBIC) measurements. The photocatalytic activity is carried out on TiO₂-Cr/PS/Si samples. It was found that the TiO₂-Cr/PS/mc-Si type structure degrades an organic pollutant (amido black) under ultraviolet (UV) light. A noticeable degradation of the pollutant is obtained for a Cr doping of 2 at. %. This result is discussed in light of LBIC and photoluminescence measurements.     

Ultrasonic velocity measurements in isobutyric acid - water binary mixtures over the temperature range from 300.15 to 313.15 K

We measured the ultrasonic velocity, U, density, ρ, and viscosity, η in Isobutyric acid - water binary liquid mixtures over the entire composition range at temperatures ranging from 300.15 to 313.15 K under atmospheric pressure. The experimental data values were analyzed to determine, various acoustical parameters: adiabatic compressibility, β, acoustic impedance, Z, free length, L_f, free volume, V_f, molar volume, V_m, relaxation time, τ, absorption coefficient, α/f², internal pressure, π_i, Gibb’s free energy, ΔG, cohesive energy, CE, Wada’s constant, W, Rao’s constant, R_m and relative association, R_A. The variation of these parameters versus the mixture composition was explained on the basis of the intermolecular interactions between the components of the mixture.     

Storage effects on dielectric properties of eggs from 10 to 1800 MHz

ABSTRACT:  The dielectric constant and loss factor of egg albumen and egg yolk over the frequency range from 10 to 1800 MHz were measured at 24 °C at weekly intervals during 5-wk storage at 15 °C. Moisture and ash contents of albumen and yolk, as well as Haugh unit and yolk index, were also measured. The dielectric constant and loss factor of albumen were higher than those of yolk. Linear relationships were evident between the log of frequency, below about 1000 MHz, and the log of loss factor of albumen as well as that of yolk. The dielectric constants of albumen and yolk at 10 MHz were lower than those of fresh albumen and yolk when eggs were stored at 15 °C for 1 wk. However, after 2 wk in storage these dielectric constants rose and remained at higher levels for the rest of the 5-wk period. At frequencies of 100 MHz and higher, the dielectric constant was essentially constant during the entire storage period. Storage had much less influence on the loss factor of either albumen or yolk. In general, the moisture content and ash content of albumen and yolk decreased slightly as eggs aged. The moisture content of yolk increased somewhat with storage, and there was a corresponding decrease in albumen moisture content. The freshness qualities, Haugh unit and yolk index, also decreased as eggs aged. No obvious correlation between dielectric properties and moisture content, ash content, Haugh unit, or yolk index was observed.