An efficient approach for face recognition based on common eigenvalues

In this paper, a simple technique is proposed for face recognition among many human faces. It is based on the polynomial coefficients, covariance matrix and algorithm on common eigenvalues. The main advantage of the proposed approach is that the identification of similarity between human faces is carried out without computing actual eigenvalues and eigenvectors. A symmetric matrix is calculated using the polynomial coefficients-based companion matrices of two compared images. The nullity of a calculated symmetric matrix is used as similarity measure for face recognition. The value of nullity is very small for dissimilar images and distinctly large for similar face images. The feasibility of the propose approach is demonstrated on three face databases, i.e., the ORL database, the Yale database B and the FERET database. Experimental results have shown the effectiveness of the proposed approach for feature extraction and classification of the face images having large variation in pose and illumination.     

Preservation of strawberries by modified atmosphere packages with other treatments

The impact of modified atmosphere packaging (MAP), in combination with ozone treatment and an edible film coating, on the preservation of strawberries was studied. A combination of 2.5% O₂ with 15% CO₂ was the optimum gas composition for the MAP of strawberries and prolonged shelf‐life by 4–6 days. When the strawberries were pre‐treated with a 4.3 mg/m³ ozone water dip and an edible coating prior to packaging, the shelf‐life was extended to 8–10 days. The results showed that two treatments [No.1: polyvinyl alcohol 134 (2%); monostearatacylglycerol (0.5%); phytic acid (0.05%); sorbitol (0.05%); sodium alginate (0.1%); absolute alcohol (8%): No.2: polyvinyl alcohol 134(1%); soluble starch (1%); glucose (1%); sucrose (1%); sodium alginate (0.1%); sorbitol (0.05%)] gave the best effects on strawberry quality and shelf‐life. All treatments (Nos 1–4) were obviously superior to check experiments for soluble sugar, ascorbic acid, acidity and anthocyanin. Furthermore, the treatments gave superior results for browning index, commodity ratio and permeability of the cell membrane. Copyright © 2006 John Wiley & Sons, Ltd.     

Energy harvesting from far field RF signals

In this article, an alternative source of energy harvesting is proposed. It is based on the concept of charge pump electronics circuit and radio frequency (RF) signal amplifier. The RF signals are acquired by the Dickson charge pump circuit, amplified, and converted into a desired DC signal. To ensure the maximum power extraction, the proposed energy harvester circuit includes multiple circuit level approach. The diode‐capacitor charge pump generated the step‐up stage in the system. The proposed idea is designed and implemented using a suitable hardware successfully. Initially, the designed circuit is simulated and tested using the MultiSim software and then hardware implemented to obtained the desired 1‐5 V DC signal. The presented circuit can be used in various applications such as electronic devices charging, power supply, energy harvesting, etc.     

Tailoring new bisphenol a ethoxylated shape memory polyurethanes

Shape memory polyurethanes (SMPUs) have generated great attention because of their unique properties. These properties are result of a particular molecular structure consisting of flexible molecular chains with low glass transition temperatures alternating with hard urethane segments. In this field, bisphenol A (BA) has been used for a long time as chain extender due to the good properties of the obtained SPMU materials. Nevertheless, the high toxicity of this compound has caused a high decrease on its use. For this reason, it has been selected a lower toxicity compound, bisphenol A ethoxylate (BAE). In this work, it is described a new SMPUs based on BAE and the influence of the hard segment on the thermo-mechanical properties and shape memory capacity. For that, both the proportion of the components and the diisocyanate employed (2,4-toluene diisocyanate (TDI), 4,4′-methylene bis(phenylisocyanate) (MDI) or a TDI/MDI mixture) have been modified. Then, depending on the molecular architecture achieved, the polyurethanes present different properties, which were studied by different techniques, such as thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and dynamic-mechanical thermal analysis (DMTA). It has been observed that glass transition temperature (T_g) increases as the hard phase content in the PU samples increases. In addition, T_g-MDI > T_g-MDI-TDI > T_g-TDI, so it is possible to control the T_g of the material, that is, shape memory transition temperature varying the diisocyanate. Finally, the shape memory capacity of the PUs was evaluated by thermo-mechanical analysis (TMA). All the synthesized PUs have shown good shape memory effect with fixation ratios up to 80% and recovery ratios close to 100%.     

Synthesis of monodispersed prolate spheroid shaped paramagnetic carbon

We demonstrate a single step, efficient, catalyst-and-solvent-free and scalable process for the synthesis of monodisperse, prolate spheroid shaped carbon (PSC) with 3 μm polar and 1.5 μm equatorial diameters by thermolysis of refined corn oil in a closed SS reactor at 700 °C. The autogenic pressure and in situ mass spectra during the thermolysis of corn oil were measured to gain insight on the reaction products as a function of temperature. We have characterized the morphology, structure, composition and magnetic property of PSC by using SEM, EDX, XRD, pair distribution function (PDF), solid state ¹³C NMR, Raman spectroscopy and EPR. We propose a putative mechanism for their formation by using all the complementary data.     

MHP‐OSGi convergence: a new model for open residential gateways

Nowadays, we are living in a time of important technological changes that affect our lives at home and our communication with the outside world. Among them, the developments in Interactive Digital TV (IDTV) and the smart home field can be considered as particularly important. Related to the former, the new Set‐Top Boxes (STBs) are not only a decoder for digital television broadcast but also an entry point to the Information Society and a suitable platform to support the execution of interactive applications. With regards to the latter, the Residential Gateways (RGs) combine different network technologies to allow the connection of different electronics devices and appliances at home, not only with each other but also with the Internet. Since there is no widespread consensus about the configurations and functions of the RGs, we propose to coordinate the two aforementioned worlds by extending the functionality of STBs to become a RG. Our proposal consists of merging the Multimedia Home Platform (MHP), one of the main standard frameworks for IDTV, with Open Service Gateway Initiative (OSGi), the most widely used open platform to set up RGs. To overcome the radically different nature of these specifications—the function‐oriented MHP middleware and the service‐oriented OSGi framework—we define a new kind of application, coined as XbundLET. This application is able to bridge the gap between the two frameworks and make their interaction feasible. We also show how this proposal has the potential to enable the production of scenarios that cannot currently be put into practice in a natural way. Copyright © 2006 John Wiley & Sons, Ltd.     

The effectiveness of static hold-up for absorption with a chemical reaction in a packed trickle bed: General order kinetics

The effectiveness f of the intetfacial area of the static hold-up for absorption with a chemical reaction in a packed trickle bed depends upon both the hydrodynamics and the chemical kinetics. The dependence of f on operating conditions is investigated for a general [m,n] order kinetics, for a liquid phase controlled absorption process. The chemical reaction is assumed to be fast. The results are presented graphically for n > 0. Analytical expressions are developed for the special case of n =0.