3D Face Recognition Using Simulated Annealing and the Surface Interpenetration Measure

This paper presents a novel automatic framework to perform 3D face recognition. The proposed method uses a Simulated Annealing-based approach (SA) for range image registration with the Surface Interpenetration Measure (SIM), as similarity measure, in order to match two face images. The authentication score is obtained by combining the SIM values corresponding to the matching of four different face regions: circular and elliptical areas around the nose, forehead, and the entire face region. Then, a modified SA approach is proposed taking advantage of invariant face regions to better handle facial expressions. Comprehensive experiments were performed on the FRGC v2 database, the largest available database of 3D face images composed of 4,007 images with different facial expressions. The experiments simulated both verification and identification systems and the results compared to those reported by state-of-the-art works. By using all of the images in the database, a verification rate of 96.5 percent was achieved at a False Acceptance Rate (FAR) of 0.1 percent. In the identification scenario, a rank-one accuracy of 98.4 percent was achieved. To the best of our knowledge, this is the highest rank-one score ever achieved for the FRGC v2 database when compared to results published in the literature.     

A fast time-domain algorithm for the simulation of switching powerconverters

An efficient algorithm for the simulation of switched-mode power converters is developed. A Chebyshev series expansion is used to effectively solve the differential equations describing the system in each topology. The power of the new simulation technique lies both in the simple, but accurate, polynomial approximation for the state transition matrices and in the ability to explicitly obtain the instants at which the switching of the circuit topology takes place. The simulation technique is illustrated with reference to a simple Buck converter operating at a constant frequency. The derivation of the new algorithm is presented and its performance is analyzed. The case of a rapidly varying input forcing function is analyzed. Examples illustrating the generality and the computational efficiency of the algorithm are presented     

Thermo-Elastic Dynamic Instability (TEDI)—a review of recent results

Frictional instabilities arise in a number of engineering and scientific contexts, when the presence of friction renders unstable the uniform motion between parts under nominally uniform conditions. Various classes of friction instabilities exist, those involving friction weakening with speed, and those at constant coefficient of friction. In the latter class, in turn, there are Dynamic Instabilities (DI) and Thermo-Elastic Instabilities (TEI). Recently, by including inertia terms in the formulations of the simple models already studied, the merging of TEI and DI has shown that, although the coupling of dynamic and thermal terms is generally weak (given the significant difference in the typical time scales of the two processes), thermal effects are capable of making otherwise neutrally stable dynamic modes unstable, rendering the new form of instability TEDI (ThermoElastoDynamic Instability) potentially interesting in a number of applications. Some results involving 1D and 2D models of TEDI are reviewed.     

Color‐separating backlight for improved LCD efficiency

Abstract— A large part of the light generated in a backlight is usually absorbed in the color filters of the liquid‐crystal display. A new backlight system that uses a grating to split the white light into different colors and a lens array to focus this light onto the pixels is presented. The absorbing filters can be eliminated and efficiency is improved. The system is characterized, as well as its different components.     

Effects of ingredients and process conditions on 'Amaretti' cookies characteristics

This research aimed at determining the influence of different factors (i.e. ingredients and process conditions) on the most important characteristics defining consumers' appreciation of 'Amaretti' cookies using DOE (design of experiment) technique. A different recipe than the original one was used in the manufacturing of the cookies, where saccharose was partially replaced with fructose and bamboo fibre was added as a new ingredient. Besides fructose/saccharose ratio and fibre, the effect of egg white, baking time and baking temperature on quality responses (hardness, water activity, moisture content and colour) of 'Amaretti' was measured by using a fractional factorial design in a screening test. Responses were affected mostly by changes in temperature and fructose/saccharose ratio levels and then by baking time; bamboo fibre had a statistically significant influence only on hardness. The power of fit of the regression models was significant for all four responses and had R ² value in the range of 0.886–0.997. However, the power of prediction was significant only for hardness, moisture content and colour and had Q ² value in the range of 0.584–0.965. The mathematical model for water activity resulted inappropriate to explain the link between factors and response. The achieved results can represent a useful tool to address and facilitate the next phase of optimisation.     

Disinfection of Dental Instruments Contaminated with Streptococcus mutans Using Ozonated Water Alone or Combined with Ultrasound

Ozone gas diluted in water has been shown to produce significant results in terms of the elimination of microorganisms. Streptococcus mutans is the etiologic agent of dental caries. Methods using water containing ozone and an ultrasonic cleaner were employed for the disinfection of a curette. Streptococcus mutans was grown in a selective medium. The curette was submitted to disinfection by water containing ozone, by ultrasound, and then both techniques were combined. The results show that either method produced a significant microbial reduction, but the efficacy of both methods combined was greater. This method of disinfection proved to be both viable and cheap.