Resistive hybrid matrix realisation using operational amplifiers

A new realisation structure for an arbitrary hybrid matrix H of resistive n-port networks using resistors and operational amplifiers is proposed in this letter.     

ECG beat recognition using fuzzy hybrid neural network

This paper presents the application of the fuzzy neural network for electrocardiographic (ECG) beat recognition and classification. The new classification algorithm of the ECG beats, applying the fuzzy hybrid neural network and the features drawn from the higher order statistics has been proposed in the paper. The cumulants of the second, third, and fourth orders have been used for the feature selection. The hybrid fuzzy neural network applied in the solution consists of the fuzzy self-organizing subnetwork connected in cascade with the multilayer perceptron, working as the final classifier. The c-means and Gustafson-Kessel algorithms for the self-organization of the neural network have been applied. The results of experiments of recognition of different types of beats on the basis of the ECG waveforms have confirmed good efficiency of the proposed solution. The investigations show that the method may find practical application in the recognition and classification of different type heart beats.     

Neural network for estimation of parameters of sinewave

The parameters of sinusoidal waves are estimated using a neural computing network. The method presented offers advantages in speed and efficiency over existing estimates techniques.<>     

Twelve-channel strained-layer InGaAs-GaAs-AlGaAs buriedheterostructure quantum well laser array for WDM applications byselective-area MOCVD

Selective-area epitaxy is used to fabricate a twelve-channel strained layer InGaAs-GaAs-AlGaAs buried heterostructure quantum well laser array suitable for wavelength division multiplexing applications. The measured wavelength separation between elements is 1.9 nm, in good agreement with the 2 nm design value     

Improving the accuracy of prediction of PM10 pollution by the wavelet transformation and an ensemble of neural predictors

The paper presents the application of wavelet transformation and neural network ensemble to the accurate forecasting of the daily average concentration of particulate matter of diameter up to 10 μm (PM₁₀). Few neural predictors are applied: the multilayer perceptron, radial basis function, Elman network and support vector machine as well as one linear ARX model. They are used for prediction in combination with wavelet decomposition, forming many individual prediction results that will be combined in an ensemble. The important role in presented approach fulfills the wavelet transformation and the integration of this ensemble. We have proposed solution applying the additional neural network responsible for the final forecast (integration of all particular prediction results). The numerical experiments for prediction of the daily concentration of the PM₁₀ pollution in Warsaw are presented. They have shown good overall accuracy of prediction in terms of all investigated measures of quality.     

Support vector machine for fault diagnosis of the broken rotor bars of squirrel-cage induction motor

The paper presents an automatic computerized system for the diagnosis of the rotor bars of the induction electrical motor by applying the support vector machine. Two solutions of diagnostic system have been elaborated. The first one, called fault detection, discovers only the case of the fault occurrence. The second one (complex diagnosis) is able to find which bars have been damaged. The most important problem is concerned with the generation and selection of the diagnostic features, on the basis of which the recognition of the state of the rotor bars is done. In our approach, we use the spectral information of the motor current, voltage and shaft field of one phase registered in an instantaneous form. The selected features form the input vector applied to the support vector machine, used as the classifier. The results of the numerical experiments are presented and discussed in the paper.     

980-nm master oscillator power amplifiers with nonabsorbing mirrors

High-power master oscillator power amplifiers with nonabsorbing mirrors have been fabricated. These devices exhibit 1.0 and 1.5 W of single-frequency diffraction-limited continuous-wave optical powers at relatively low-amplifier currents of 1.75 and 2.6 A, respectively. These devices operate with a single longitudinal mode with a 40-dB sidemode suppression ratio over the entire amplifier current range without any longitudinal mode hops as a result of the very low optical feedback from the PA facet. Coupling of over 500 mW into a single-mode fiber is also achieved     

Asymmetric cladding InGaAs-GaAs-AlGaAs ridge waveguide distributed Bragg reflector lasers with operating wavelengths of 915-935 nm

The design and operation of InGaAs-GaAs-AlGaAs asymmetric cladding ridge waveguide distributed Bragg reflector lasers is presented. Targeted for the remote sensing of water vapor with absorption lines in the /spl lambda//spl sim/930 nm region, these devices operate CW with threshold currents as low as 11 mA and slope efficiencies as high as 0.37 W/A. They also operate with over 30-dB side-mode suppression, and the typical CW characteristic temperature, T/sub 0/, is 95 K.     

An open-label dose comparison study of ondansetron for the prevention of emesis associated with chemotherapy prior to bone marrow transplantation

The potentialities of polarization microscopy has been greatly increased by using specific stains for selective enhancement of the optical anisotropy of a macromolecular constituent of cells and tissues. Such stainings have proved to be especially useful in exploring the spatial orientation pattern of the extracellular matrix components. The retardation value, which characterizes quantitatively the degree of submicroscopic orientation, can be measured traditionally with a compensator plate. This technique, however, is time-consuming and greatly dependent on visual judgment. Several attempts have been made to combine digital image analysis and polarization microscopy to improve the measuring technique in unstained structures. In this paper, we summarize theoretical considerations and experimental data to show the advantages and limitations of this methodological approach when using stained and birefringent specimens. The technique we are suggesting is the measurement of the light intensity using a 12 bit cCCD camera attached to a polarized light microscope and digital image analysis system. The theoretical basis is given by the Fresnel equation describing the relationship between light intensity and retardation value. According to this, there is a sin2 function between the light intensity and the retardation value. The same relationship of these two parameters was observed in our experiments on the birefringent extracellular matrix around chondrocytes grown in agarose gel and interterritorial and territorial matrix of canine articular cartilage stained with picrosirius red. Our results suggest that the retardation values can be calculated directly from the light intensity values if the retardation value is lower than lambda/2.     

A universal optical heterostructure for photonic integratedcircuits: a case study in the AlGaAs material system

An approach for the realization of a single heterostructure for multiple optical device applications in a photonic integrated circuit environment is addressed from the standpoint of building into the heterostructure separate device features. In particular, a low compositionally graded depressed cladding laser structure is shown to have a large mode, compared to a structure optimized for maximum confinement factor, and a radiation loss an order of magnitude lower than for a structure without the inner cladding, features which are important for fiber coupling and for compact bends. By incorporating a narrow gap section into the barrier layer, a bulk electroabsorption modulator can be integrated into the same structure that contains quantum wells for optical amplifiers. Data are presented on the device properties of a single heterostructure when used as large optical cavity lasers, s-bends, and bulk electroabsorption modulators. The only laser parameter affected by the incorporation of the modulator is the transparency current density which is increased 25% over standard structures. The performance of rib delineated s-bends is exceeded only by native oxide defined small optical cavity laser structures. The electroabsorption modulator, which was activated in a disordered section under reverse bias, had a modulation depth approximately 1/3 that predicted by model studies which was attributed to the depletion electric field profile. Methods for improving the modulation depth while lowering the transparency current density are outlined