Effect of water aging on the mechanical properties of flax fiber/bio-based resin composites

Present work investigates the effect of hydrothermal aging of flax fiber-reinforced bio-based epoxy resin laminates on the mechanical and thermomechanical properties of the composites. Three different types of bio-based resins were used. Plates reinforced with eight layers plain weave flax fibers of 150 g/m², manufactured using Resin Transfer Molding (RTM), compression molding or autoclave technique depends on type of the resin. One dimensional Fickian behavior shows a good fitting to the experimental data derived from weight measurements. The water uptake at the equilibrium state in the case of 60 °C temperature was slightly greater than that at 40 °C. The mechanical properties after hydrothermal aging show a significant reduction and do not return to their initial values even after the drying process. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48787.     

Use of rosemary extract in preventing oxidation during deep-fat frying of potato chips

The effect of using a rosemary extract on the stability of oil used for frying potato chips has been evaluated. Sliced potatoes were fried intermittently in soybean oil containing a natural extract from rosemary. The conditions used for frying were 185°C for 90 s. Two separate experiments, with and without replenishment of oil, were carried out. Oil samples were taken each day, not only from the frying pans but also by extraction with hexane from the chips. Changes in the induction period of the oil samples (Rancimat method) were determined. The induction period decreased as frying progressed. The reduction in the induction period was higher in the oil free of rosemary extract, and the chips were much darker in color. The oil containing the extract showed greater antioxidant activity, and reduced darkening and rancidity of the oil. Potato chips fried in the oil with added rosemary extract were more acceptable than chips fried in oil containing no extract until the last frying. The free radical scavenging activity of rosemary extract in comparison to other natural antioxidants was also determined by the reduction of O₂ ^.- in a hypoxanthine/xanthine oxidase system.     

Data hiding based on image texture classification

In this paper, a new pattern-based fragile, semi-blind, spatial domain data hiding scheme is proposed. The Local Binary Pattern texture classification approach is used, in order to transparently and securely embed secret data into an image. Pixel values are modified in such a way that the texture satisfies the message requirements. The method is thoroughly studied and compared to other techniques in spatial domain in terms of capacity and image quality. The scheme performs well in images with smooth areas and can be used for authentication, tamper proofing, and secret communications.     

Skin color-based video segmentation under time-varying illumination

A novel approach for real-time skin segmentation in video sequences is described. The approach enables reliable skin segmentation despite wide variation in illumination during tracking. An explicit second order Markov model is used to predict evolution of the skin-color (HSV) histogram over time. Histograms are dynamically updated based on feedback from the current segmentation and predictions of the Markov model. The evolution of the skin-color distribution at each frame is parameterized by translation, scaling, and rotation in color space. Consequent changes in geometric parameterization of the distribution are propagated by warping and resampling the histogram. The parameters of the discrete-time dynamic Markov model are estimated using Maximum Likelihood Estimation and also evolve over time. The accuracy of the new dynamic skin color segmentation algorithm is compared to that obtained via a static color model. Segmentation accuracy is evaluated using labeled ground-truth video sequences taken from staged experiments and popular movies. An overall increase in segmentation accuracy of up to 24 percent is observed in 17 out of 21 test sequences. In all but one case, the skin-color classification rates for our system were higher, with background classification rates comparable to those of the static segmentation.     

Less Impact Better Service (LIBS)

We discuss a new packet service paradigm, called “Less Impact Better Service” (LIBS). In simple terms, LIBS primarily schedules packets based on the delay they cause and cancels service differentiation policies when the cumulative delay due to prioritization becomes significant for non-prioritized packets. Based on LIBS, we evaluate different service policies that prioritize small packets using different service boundaries and we show that, by and large, LIBS satisfies better a number of applications with diverse demands in delay and throughput. We emphasize on Voice over IP applications, which are delay-sensitive but also utilize small packets and rates. Among other traditional performance measures, we also measure fairness in the context of LIBS, that is, we address the question whether the delay experienced per flow is proportional to the delay caused by that flow. We obtained very promising simulation results.     

Principal motion components for one-shot gesture recognition

This paper introduces principal motion components (PMC), a new method for one-shot gesture recognition. In the considered scenario a single training video is available for each gesture to be recognized, which limits the application of traditional techniques (e.g., HMMs). In PMC, a 2D map of motion energy is obtained per each pair of consecutive frames in a video. Motion maps associated to a video are processed to obtain a PCA model, which is used for recognition under a reconstruction-error approach. The main benefits of the proposed approach are its simplicity, easiness of implementation, competitive performance and efficiency. We report experimental results in one-shot gesture recognition using the ChaLearn Gesture Dataset; a benchmark comprising more than 50,000 gestures, recorded as both RGB and depth video with a Kinect?camera. Results obtained with PMC are competitive with alternative methods proposed for the same data set.     

OPC-SMS: a wireless gateway to OPC-based data sources

This paper describes OPC-SMS gateway, a platform that integrates IP networks with the Short Message Service (SMS), in order to deliver an integrated service for access to data sources conforming to Object Linking and Embedding for Process Control (OPC) standard specifications, through SMS-enabled mobile devices. The gateway supports pull and push services in order to support both request-based and alarm/scheduled-based notifications, respectively. The proposed architecture is based entirely on the ubiquitous HyperText Transport Protocol (HTTP), Simple Object Access Protocol (SOAP), Extensible Markup Language (XML) protocols, and the Global System for Mobile communication (GSM) network and thus exploits the network infrastructure already in place. The capability of accessing different types of OPC data sources (real-time and historical) by any SMS-enabled device consists of a highly flexible service, supporting mobility and event-based notification. A pilot implementation of our approach has been tested in a large-scale installation for accessing OPC data sources of several automation subsystems in a hospital.