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1.
Epilepsy is a neurological disorder which is characterized by transient and unexpected electrical disturbance of the brain. The electroencephalogram (EEG) is a commonly used signal for detection of epileptic seizures. This paper presents a new method for classification of ictal and seizure-free EEG signals. The proposed method is based on the empirical mode decomposition (EMD) and the second-order difference plot (SODP). The EMD method decomposes an EEG signal into a set of symmetric and band-limited signals termed as intrinsic mode functions (IMFs). The SODP of IMFs provides elliptical structure. The 95% confidence ellipse area measured from the SODP of IMFs has been used as a feature in order to discriminate seizure-free EEG signals from the epileptic seizure EEG signals. The feature space obtained from the ellipse area parameters of two IMFs has been used for classification of ictal and seizure-free EEG signals using the artificial neural network (ANN) classifier. It has been shown that the feature space formed using ellipse area parameters of first and second IMFs has given good classification performance. Experimental results on EEG database available by the University of Bonn, Germany, are included to illustrate the effectiveness of the proposed method.  相似文献   
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Chemical method has been used to prepare cadmium sulphide by using cadmium, hydrochloric acid and H2S. The reflection spectra of covered and uncovered sintered films of CdS have been recorded by ‘Hitachi spectrophotometer’ over the wavelength range 300–700 nm. The energy band gaps of these films have been calculated from reflection spectra. It is found that the energy band gap of both films is same as 2.41 eV. It is indicated that energy band gap of these films does not change. This value of band gap is in good agreement with the value reported by other workers. The measurement of photocurrent has also been carried out using Keithley High Resistance meter/ Electrometer. This film shows the high photosensitivity and high photocurrent decay. Thus so obtained films are suitable for fabrication of photo detectors and solar cells.  相似文献   
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Multimedia Tools and Applications - Leap motion sensor provides a new way of interaction with computers or mobile devices. With this sensor, users can write in air by moving palm or finger, thus,...  相似文献   
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A step‐up pulse width modulation (PWM) direct current (DC)–DC converter is presented in this paper, which has its origin in quasi Z‐source inverter. Analysis of this converter in steady state is presented, and relevant expressions are derived for the proposed converter operating in continuous conduction mode. The power loss expressions for each component of the converter are derived, and thereby, obtained expressions for overall converter efficiency are presented. Further, a dynamic model is derived to design an appropriate controller for this converter. The simulation and experimental results are presented to support the theoretical analysis. The advantages such as continuous input current, high step‐up gain at lower duty ratio, and common ground for source, load, and switch makes the converter suitable for renewable energy applications. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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The cadmium sulfide/polystyrene (CdS/PS) nanocomposites with concentration (0, 2, 4, 6, and 8) wt% of CdS nanoparticles were prepared by solution casting method and characterized through fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) measurements. The particle size of nanoparticles is found to be around 15 nm. Glass transition and mechanical behavior of CdS/PS nanocomposites were investigated using dynamic mechanical analyzer (DMA). The mechanical properties such as Young's modulus and tensile strength were determined at room, as well as at elevated temperatures through their stress–strain curves. The result shows that glass transition temperature (Tg) is shifted toward the higher temperature after the addition of CdS nanoparticles. The mechanical properties increased at low wt% loading of CdS nanoparticles and decreased for higher wt% loading of CdS nanoparticles. It was also found that mechanical properties decline with increase in the temperature. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers  相似文献   
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In the present study ZnSe quantum dots (QDs) were synthesized by chemical co-precipitation method using mercaptoethanol as the capping agent. These nanostructures were characterized for structure and surface morphology by using X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectrometry respectively. The average size of ZnSe quantum dots from XRD and HRTEM is found to be 4–5 nm having cubic crystalline phase. Effect of annealing temperature, which were determined as phase transformation temperatures (299 and 426 °C) using differential scanning calorimetry has been investigated for structural and thermal stability of QDs. The XRD of annealed samples at temperatures 325 and 442 °C (slightly higher than the temperatures corresponding to two crystallization peaks in the DSC scan) have been carried out to find structural changes corresponding to these annealing temperatures. Sample annealed at 325 °C showed no change in the phase except improvement in intensity of peaks (crystallinity) whereas sample annealed at 442 °C showed transitions from cubic phase of ZnSe to ZnO and orthorhombic phases of ZnSeO4, ZnSeO3. Emergence of ZnO peaks in the XRD pattern of annealed samples have been further verified by Raman spectroscopy of the annealed samples. Besides this crystallization kinetics of ZnSe quantum dots has been employed to determine activation energies of these transitions due to oxidation by employing Kissinger, Augis Bennett and Ozawa’s models. Higher activation energy of crystallization corresponding to first crystallization peak shows that the cubic phase is more thermally stable.  相似文献   
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Flow is widely considered one of the primary drivers of instream ecological response. Increasingly, hydroecological models form the basis of integrated and sustainable approaches to river management, linking flow to ecological response. In doing so, the most ecologically relevant hydrological variables should be selected. Some studies have observed a delayed macro‐invertebrate (ecological) response to these variables (i.e. a cumulative inter‐annual effect, referred to as multi‐annual) in groundwater‐fed rivers. To date, only limited research has been performed investigating this phenomenon. This paper examines the ecological response to multi‐annual flow indicators for a groundwater‐fed river. Relationships between instream ecology and flow were investigated by means of a novel methodological framework developed by integrating statistical data analysis and modelling techniques, such as principal component analysis and multistep regression approaches. Results demonstrated a strong multi‐annual multi‐seasonal effect. Inclusion of additional antecedent flows indicators appears to enhance overall model performance (in some cases, goodness of fit statistics such as the adjusted R‐squared value exceeded 0.6). These results strongly suggest that, in order to understand potential changes to instream ecology arising from changing flow regimes, multi‐annual and multi‐seasonal relationships should be considered in hydroecological modelling. © 2017 The Authors River Research and Applications Published by John Wiley & Sons Ltd.  相似文献   
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This is the novel report on the rapid synthesis of single phase BiFeO3 nanorods by novel hot wall assisted spray pyrolysis system. The deposition has been carried out in an indigenously fabricated system and the entire process is completed in 4 s time duration. The structural, morphological, optical and magnetic properties of BiFeO3 nanorods have been studied in the work. The mechanism of growth of BiFeO3 nanorods has been explained extensively. The magnetic studies carried out with SQUID-VSM results BiFeO3 nanorods showing higher saturated magnetization in comparing with previous reports.  相似文献   
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