Object tracking based on an online learning network with total error rate minimization

This paper presents a visual object tracking system which is tolerant to external imaging factors such as illumination, scale, rotation, occlusion and background changes. Specifically, an integration of an online version of total-error-rate minimization based projection network with an observation model of particle filter is proposed to effectively distinguish between the target object and the background. A re-weighting technique is proposed to stabilize the sampling of particle filter for stochastic propagation. For self-adaptation, an automatic updating scheme and extraction of training samples are proposed to adjust to system changes online. Our qualitative and quantitative experiments on 16 public video sequences show convincing performances in terms of tracking accuracy and computational efficiency over competing state-of-the-art algorithms.     

Random multispace quantization as an analytic mechanism for BioHashing of biometric and random identity inputs

Biometric analysis for identity verification is becoming a widespread reality. Such implementations necessitate large-scale capture and storage of biometric data, which raises serious issues in terms of data privacy and (if such data is compromised) identity theft. These problems stem from the essential permanence of biometric data, which (unlike secret passwords or physical tokens) cannot be refreshed or reissued if compromised. Our previously presented biometric-hash framework prescribes the integration of external (password or token-derived) randomness with user-specific biometrics, resulting in bitstring outputs with security characteristics (i.e., noninvertibility) comparable to cryptographic ciphers or hashes. The resultant BioHashes are hence cancellable, i.e., straightforwardly revoked and reissued (via refreshed password or reissued token) if compromised. BioHashing furthermore enhances recognition effectiveness, which is explained in this paper as arising from the random multispace quantization (RMQ) of biometric and external random inputs     

Development of a Highly Selective,Sensitive, and Fast Response Upconversion Luminescent Platform for Hydrogen Sulfide Detection

Hydrogen sulfide (H₂S) has been recognized as one of most important gaseous signaling molecules mediated by a variety of physiological and pathological processes. Yet, its functions remain largely elusive due to the lack of potent monitoring methods. Hereby this issue is addressed with a powerful new platform—dye‐assembled upconversion nanoparticles (UCNPs). A series of chromophores with different absorption bands and fast responses towards H₂S is combined with UCNPs and results in a library of H₂S sensors with responsive emission signals ranging from the visible to the near‐infrared (NIR) region. These nanoprobes demonstrate highly selective and rapid responses to H₂S in vitro and in cells. Furthermore, H₂S levels in blood can be detected using the developed nanoprobes. Hence the reported H₂S sensing platform can serve as a powerful diagnostic tool to research H₂S functions and to investigate H₂S‐related diseases.     

Exploiting the Plackett–Burman design to examine the formulation effect on curing characteristics of oil palm ash-filled acrylonitrile butadiene rubber compounds

The present paper is focused on exploiting Plackett–Burman design to examine the formulation effect of various chemical components content on the curing characteristics of oil palm ash (OPA)-filled acrylonitrile butadiene rubber (NBR) compound. The filled-NBR compound was prepared by conventional laboratory-sized two roll mill and cured using sulfuric system. Six independent variables such as content of zinc oxide, stearic acid, N-isopropyl-N′-phenyl-p-phenylenediamine, N-cyclohexyl-2-benzothiazole sulfenamide (CBS), sulfur, and even OPA filler were carried out to screen their significant effect on the curing characteristics of NBR compound. The scorch time, optimal cure time, minimum torque, and maximum torque were selected as a response. Results showed that the scorch time and the optimal cure time were significantly affected by CBS, whereas the minimum torque and maximum torque were significantly affected by OPA and sulfur, respectively, within the studied range. Among the chemical components under study, zinc oxide and stearic acid had the least effect on the curing properties of NBR compound. Analysis of variances for all factorial models demonstrated that the model was significant with P value <0.05 while the regularity (R ²) of all models was greater than 0.9. Lastly, the optimal chemical concentrations were predicted to acquire the optimal condition of the curing system for filled-NBR compound.     

The preparation,characterization and photocatalytic activity of radical-shaped CeO2/ZnO microstructures

This paper uses a wet-chemical precipitation route to prepare radical-shaped ZnO microprisms and to deposit Cerium oxide (CeO₂) on the surface of ZnO, to form CeO₂/ZnO microstructures. The samples are characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectroscopy. Their catalytic activity is also evaluated using methylene blue (MB) as a detection reagent. CeO₂/ZnO systems exhibit higher UV absorption and transparency in the visible region. The experimental results show that the deposition of CeO₂ nanospecies is successful and that the radical-shaped microstructures of ZnO are well maintained. The CeO₂/ZnO microstructures exhibit a much greater intensity of UV-light absorptivity and much higher photocatalytic activity than those of radical-shaped ZnO microprisms.     

Computer simulation of viscoelastic flow at the entry region

Non-Newtonian flow has a nonlinear constitutive relationship with an advective nature. It was found that in highly advective (convective) problems, the Galerkin formulation “under-diffused,” resulting in divergence at low elastic numbers. The use of the Streamline-Upwinding (SU) method improved the solution, especially when used with the Phan-Thien-Tanner (PTT) model. At the boundary discontinuity, however, the stress gradient did not necessarily flow along the streamline direction, and oscillations still remained at the corner. The Discontinuity-Capturing (DC) method resolved this problem by applying control in the direction of the stress gradient rather than the stream line direction, and a smoother solution at the corner region was achieved.     

Effect of constitutive models on the numerical simulation of viscoelastic flow at an entry region

The poor solutions of numerical simulations at a contraction has often been attributed to the numerical scheme used. However, the solution of a numerical simulation is also highly dependent on the constitutive equation. A study of various constitutive equations on the simulation of the 4:1 contraction flow is made in this paper, and their effects on the results analyzed. The constitutive models considered include the Upper Convected Maxwell model, the Oldroyd-B model, the White-Metzner model, the Phan-Thien-Tanner model and the Giesekus-Leonov model. It was found that although the Phan-Thien-Tanner model gave the best results, the solution at higher shear rates were still not satisfactory.     

Effect of temperature and chainlength on the densities and molal volumes ofn-alkyl chlorides

The densities ofn-alkyl chlorides from pentyl chloride to hexadecyl chloride were determined at temperatures between 15–80°C at 5°C intervals. The densities increase linearly with temperature and chainlength. A four-constant equation, V=n/(−3.6640 × 10⁻⁵ T+0.07151)+1/(−5.6526 × 10⁻⁵ T+0.04243), was formulated. This formula accurately predicted the molal volume and, hence, the density for all then-alkyl chlorides at any temperature within the range.