Robust digital control of a DC–DC buck converter with low frequency samplings

A robust DC?CDC converter which can covers extensive load change and also input voltage changes with one controller is needed. Then the demand to suppress output voltage change becomes still severer. We propose an approximate 2-degree-of-freedom (2DOF) digital controller which realized start-up response and dynamic load response independently. The controller makes a control bandwidth wider, and at the same time makes variations of the output voltage small at sudden changes of a load and an input voltage. In this paper, a new approximate 2DOF digital control system with additional zeros is proposed. Using the additional zeros, the second-order differential transfer characteristics between equivalent disturbances and a output voltage are realized. Therefore, the new controller makes variations of the output voltage smaller and the sudden changes of the load and the input voltage. This controller is actually implement on a DSP and is connected to the DC?CDC converter. Experimental results demonstrate that this type of digital controller can satisfy given severe specifications with low frequency sampling.     

Tung based reactive diluents for alkyd systems: Film properties

Reactive diluents were prepared from tung oil via a Diels–Alder reaction with three different dienophiles: methacryloxypropyl trimethoxysilane (TOMAS), 2,2,2-trifluoroethyl methacrylate (TOF) and triallyl ether acrylate (TOTAE). The reactive diluents were mixed with a long oil soya alkyd, a metal drier package, and a wetting agent; and then cured. Formulations were prepared as a function of reactive diluent type and wt%. Tensile, thermomechanical, and coatings properties were evaluated after curing the films. The addition of two reactive diluents, TOMAS and TOTAE, improved the tensile strength and tensile modulus of the alkyd. The addition of the diluents, however, did not significantly change the elongation at break compared to the alkyd in any of the systems. Also, the addition of TOMAS and TOTAE increased both the crosslink density and glass transition temperature of the alkyd. Basic film properties including hardness, solvent resistance, impact resistance, adhesion, and gloss were not adversely affected by the introduction of any of the tung oil based diluents.     

A Method of Motion-Estimation-Based H.264 Video Coding Using Optimal Search-Range

Wireless Personal Communications - In multi-view video coding, inter-view and temporal redundancies decrease the coding efficiency and video quality, and they need to be eliminated. This paper...     

Electroencephalography‐based feature extraction using complex network for automated epileptic seizure detection

Electroencephalography signals are typically used for analyzing epileptic seizures. These signals are highly nonlinear and nonstationary, and some specific patterns exist for certain disease types that are hard to develop an automatic epileptic seizure detection system. This paper discussed statistical mechanics of complex networks, which inherit the characteristic properties of electroencephalography signals, for feature extraction via a horizontal visibility algorithm in order to reduce processing time and complexity. The algorithm transforms a time series signal into a complex network, which some features are abbreviated. The statistical mechanics are calculated to capture distinctions pertaining to certain diseases to form a feature vector. The feature vector is classified by multiclass classification via a k‐nearest neighbor classifier, a multilayer perceptron neural network, and a support vector machine with a 10‐fold cross‐validation criterion. In performance evaluation of proposed method with healthy, seizure‐free interval, and seizure signals, firstly, input data length is regarded among some practical signal samples by optimizing between accuracy‐processing time, and the proposed method yields outstanding performance on the average classification accuracy for 3‐class problems mainly for detection of seizure‐free interval and seizure signals and acceptable results for 2‐class and 5‐class problems comparing with conventional methods. The proposed method is another tool that can be used for classifying signal patterns, as an alternative to time/frequency analyses.     

A Method of Football-Offside Detection Using Multiple Cameras for an Automatic Linesman Assistance System

In offside detection during a football match, afterimage and occlusion confuse the linesman and the referee, and this confusion can cause judgment errors. This paper proposes a method of football-offside detection using multiple cameras in an automatic linesman assistance system. In this method, multiple cameras and offside detection units are installed as a hardware system, and offside will be alerted when at least one of the offside detection units detects offside. In an offside detection unit, when the offside position is determined, offside is immediately judged in the case in which the ball is passed from an attacker to another attacker who is located nearer the opponent-goal line than the most-back defender and the ball. The vertical lines that represent these attackers, defenders and ball are used as their positions for logically judging the offside. Experiments were performed using video clips from 381 tournaments of English Premier Leagues from 2016 to 2017. The results showed 98.50% accuracy compared with the expert.

     

Indigo carmine degradation in the presence of maltose and ethanol

The majority of important reactions in beer are associated with the action of oxygen during malting and brewing. With respect to oxygen, beer is considered to possess a relatively strong reducing environment. The gradual reduction of oxygen gives rise to reactive oxygen species (ROS) capable of attacking beer components that are important to consumers. Indigo carmine (IC) bleaching was used to prove ROS formation formed by oxidation of beer energy sources such as maltose and ethanol. This paper examines oxygen radical oxidation of organic matter in the presence of the radical initiator potassium peroxodisulphate. A mixture of organic sources of energy such as maltose and ethanol, oxygen, radical initiator and cupric ions generates ROS formation in a broad range of concentrations even at room temperature. ROS irreversibly split blue dye IC into the colourless form and takes part in the radical transformation of organic matter, which is similar to its burning at low temperature or to radical oxidation of reducing agents. Other organic matter can suppress ROS formation and be incorporated into the radical chain of the pathway of its ‘cold burning’. Ethanol inhibited phenylalanine oxidation during its oxidative Maillard reaction. IC bleaching can serve as simple indicator of ROS generation in aerated food. Copyright © 2015 The Institute of Brewing & Distilling     

Single-stage electronic ballast with class-E rectifier as power-factor corrector

A single-stage high-power-factor electronic ballast with a Class-E rectifier as a power-factor corrector is proposed. A Class-E rectifier is inserted between the front-end bridge rectifier and the bulk filter capacitor to increase the conduction angle of the bridge-rectifier diode current for obtaining low line-current harmonics. The Class-E rectifier is driven by a high-frequency sinusoidal current source, which is obtained from the square-wave output voltage of the Class-D inverter through an LC series resonant circuit. A high-frequency transformer is used for impedance matching. The experimental results for a 32-W prototype ballast are given. The switching frequency was 61.3 kHz. At full power, the power factor was 0.992 and the total ballast efficiency was 88.3%. The lamp-current crest factor was about 1.36. The simulated and experimental results were in very good agreement.     

Addable Stress Speech Recognition with Multiplexing HMM: Training and Non-training Decision

In stress speech recognition, a recognition model that is capable of processing multi-stress speech needs to be designed in the view points of accuracy and add-ability. This paper proposes addable stress speech recognition with multiplexing Hidden-Markov model (HMM). To achieve multi-stress speech, we propose a multiplexing topology that combines multiple stress speech models. Since each stress affects a speech in different way, having a speech recognition model that specifically trained to recognize words effected by the stress help improve the recognition rates. However, since each stress speech model gives it own independent recognized word, we need to have an effective decision module to choose the correct word. In each stress speech model, a MFCC is applied to the input speech. The result is fed into a HMM that is segmented into N parts. Each part of the segmentation provides its own tentative recognized word which in turn is an input to the proposed non-training decision module. Based on these tentative recognized words from segments of all stress speech models, the final recognized word is decided using coarse-to-fine concept performed by a majority vote, segment-weighted difference square score and next best score, respectively. Besides neutral speech, the proposed method was verified using three stresses including angry, loud, and Lombard. The results showed that the proposed method achieved 94.7 % recognition rate comparing to 94.2 % of the training-based decision method.     

2D Pose-Invariant Face Recognition Using Single Frontal-View Face Database

Wireless Personal Communications - Personal identification systems that use face recognition work well for test images with frontal view face, but often fail when the input face is a pose view....