An efficient new method for the detection of QRS in electrocardiogram

A simple and efficient new method for QRS detection in Electrocardiogram (ECG) is proposed in this paper. Initially data is preprocessed using two stage median filter for removing baseline drift. The second stage enhances the peaks of ECG wave components by using sixth power of signal. The next stage identifies the QRS complex by taking a variable window size. The detection sensitivity (Se) and positive predictivity (+P) of CSE (Common Standards for Quantitative Electrocardiography) measurement database, MIT/BIH (Massachusetts Institute of Technology/Beth Israel Hospital) Arrhythmia database, European ST-T database and QT database are Se 99.51 & +P 99.69%, Se 99.21 & +P 99.34%, Se 99.53 & +P 99.72% and Se 99.87 & +P 99.95% respectively. These four standard databases used to perform QRS detection considered 368 cases, tested 1,006,168 beats and achieved overall average sensitivity 99.52% and positive predictivity 99.69%. The MIT/BIH Noise Stress Test Database also tested by proposed method.     

Tool path generation framework for accurate manufacture of complex 3D sheet metal parts using single point incremental forming

The prototyping of complex sheet metal parts using single point incremental forming (SPIF) requires the generation of optimal tool paths and/or tool path sequences that ensure that the formed part is within geometric design specifications. The presence of a multitude of features on complex parts leads to multiple inaccuracy inducing phenomena occurring simultaneously due to interactions between the features. This paper proposes a network analysis methodology using topological conceptual graphs to capture the effects of different phenomena on the final accuracy of a sheet metal part manufactured by SPIF. Using this framework optimized tool paths can be generated that compensate for the inaccuracy inducing behavior. Tool path generation algorithms to create partial tool paths that account for the accuracy of specific features in the part based on the proposed framework are also presented. Finally, the creation of integrated tool paths maintaining complementarity between tool paths and desired continuity behavior using non-uniform cubic B-splines is illustrated. A number of case studies demonstrating the applicability of the integrated framework are discussed, where the maximum deviations in the part are significantly reduced and the average absolute deviations for the complete part are brought down to less than 0.5 mm.     

Adaptive tracking control of an autonomous underwater vehicle

This paper presents the trajectory tracking control of an autonomous underwater vehicle(AUV). To cope with parametric uncertainties owing to the hydrodynamic effect, an adaptive control law is developed for the AUV to track the desired trajectory. This desired state-dependent regressor matrix-based controller provides consistent results under hydrodynamic parametric uncertainties.Stability of the developed controller is verified using the Lyapunov s direct method. Numerical simulations are carried out to study the efficacy of the proposed adaptive controller.     

A microfluidic device for thermal particle detection

We demonstrate the use of heat to count microscopic particles. A thermal particle detector (TPD) was fabricated by combining a 500-nm-thick silicon nitride membrane containing a thin-film resistive temperature detector with a silicone elastomer microchannel. Particles with diameters of 90 and 200 μm created relative temperature changes of 0.11 and ?0.44 K, respectively, as they flowed by the sensor. A first-order lumped thermal model was developed to predict the temperature changes. Multiple particles were counted in series to demonstrate the utility of the TPD as a particle counter.     

Effect of graft chain length of the stabilizer on dispersion polymerization of methyl methacrylate in petrol

To carry out dispersion polymerization of methyl methacrylate (MMA) in petrol, we have used a poly(MMA) grafted-poly(12-hydroxystearic acid) copolymer as the stabilizer. This special copolymer was prepared as a solution in a mixture of ethyl acetate and butyl acetate solvents. We investigated the effect of graft chain length of the stabilizer on the dispersion polymerization in petrol. We synthesized the stabilizer copolymer with n = 1–4 and determined the rate and the molecular weight of the PMMA formed. There is no dispersion polymerization for n = 1. However, for any other n, for a given stabilizer concentration, as the chain length of the graft is increased, the molecular weight as well as the rate of PMMA formation increases. As opposed to this for a given graft length as the concentration of the stabilizer increases, the molecular weight of PMMA first rises, but for a larger concentration, it begins to fall after undergoing a maximum. In this work, we modeled the heterogeneity of the reaction mass and proposed a mathematical model for dispersion polymerization of MMA in petrol. The computer results are found to conform to the experimentally observed molecular weight of the PMMA. © 1993 John Wiley & Sons, Inc.     

Lyso platelet activating factor (LysoPAF) and its enantiomer. Total synthesis and carbon-13 NMR spectroscopy

Described is a reaction sequence for the total synthesis of lyso platelet activating factor (lysoPAF; 1-O-alkyl-sn-glycero-3-phosphocholine) and its enantiomer. The procedure is versatile and yields optically pure isomers of defined chain length. The synthesis is equally suited for the preparation of lysoPAF analogues and its enantiomers with unsaturation in the long aliphatic chain. First,rac-1(3)-O-alkylglycerol is prepared by alkylation ofrac-isopropylideneglycerol with alkyl methanesulfonate followed by acid-catalyzed removal of the ketal group. The primary hydroxy group of alkylglycerol is then protected by tritylation, the secondary hydroxy group is acylated, and the protective trityl group is removed under mild acidic conditions with boric acid on silicic acid, essentially without acyl migration. Condensation of the diradylglycerol with bromoethyl dichlorophosphate in diethyl ether, hydrolysis of the resulting chloride, and nucleophilic displacement of the bromine with trimethylamine givesrac-1-O-alkyl-2-acylglycero-3-phosphocholine in good overall yield. The racemic alkylacylglycerophosphocholine is finally treated with snake venom phospholipase A₂ (Ophiophagus hannah) which affords 1-O-alkyl-sn-glycero-3-phosphocholine (lysoPAF) of natural configuration in optically pure form. The “unnatural” 3-O-alkyl-2-O-acyl-sn-glycerol-1-phosphocholine enantiomer, which is not susceptible to phospholipase A₂ cleavage, gives 3-O-alkyl-sn-glycero-1-phosphocholine upon deacylation with methanolic sodium hydroxide. Homogeneity and structure of the intermediates and final products were ascertained by carbon-13 nuclear magnetic resonance spectroscopy on monomeric solutions.     

Conductivity and viscosity studies of ethylene carbonate based solutions containing lithium perchlorate

Specific conductivities and viscosities of lithium perchlorate at four different concentrations (0.5, 1.0, 1.5 and 2.0 M) in ethylene carbonate (EC) based binary mixed solvent systems at 25°C are reported. The co-solvents chosen were tetrahydrofuran (THF), 1,2-dimethoxyethane (DME) and 1,3-dioxolane (DOL). Viscosity variations in all the three mixed solvent systems without electrolyte showed negative deviation from ideal behaviour thereby indicating the occurrence of a structure breaking effect in these three different binary systems. The increase in viscosity with increase in concentration of LiClO₄ is attributed to the structural enhancement through the formation of a solvated complex which occupies interstitials in the solvent mixtures. 1 M LiClO₄ solution shows maximum specific conductivity at 30 vol % EC for EC + DME and EC + DOL mixtures and at 50 vol % EC for EC + THF mixtures. Conductivity variations are explained on the basis of preferential solvation of lithium perchlorate by co-solvents (THF, DME and DOL) in their respective mixtures with ethylene carbonate.     

IEVCA: An efficient image encryption technique for IoT applications using 2-D Von-Neumann cellular automata

Multimedia Tools and Applications - Present era is marked by exponential growth in transfer of multimedia data through internet. Most of the Internet-of-Things(IoT) applications send images to...     

Video sequence feature extraction and segmentation using likelihood regression model

The development of digital technology is utilized by people to capture and share video frames. At present, rather than capturing images, people are interested in recording video footage for exploring information. Here, retrieval of video from large databases is challenging due to the continuous frame count. To overcome these challenges associated with the retrieval of video from available databases, this research proposed a likelihood-based regression approach for video processing. To improve the retrieval accuracy of video sequences, the proposed method utilizes a likelihood estimation technique integrated with a regression model. The likelihood estimate measures the pixel level roughly for estimating the pixel range, after which the regression approach measures the pixel level for transforming certainly blurred and unwanted pixels. In the proposed likelihood regression approach, the video is converted into a video frame and stored in a database. Query frames are taken into account by the generated database depending on the features which are used for a given video to be retrieved. The significant video retrieval performance obtained from the simulation results for the proposed likelihood-based regression model shows that the proposed model performs well over the other state-of-the-art techniques.