Influence of alloying elements on the structure and wear resistance of chilled cast iron

To work out the optimal chemical composition of wear-resistant cast iron with a pearlitic metallic matrix that is able to restore the relief of a rough surface, we investigated the properties of cast iron with different composition by the method of single factor experiment.Nizhnii Novgorod Branch of the Central Research Institute of Structural Materials Prometei. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 6, pp. 37–39, June, 1994.     

Observations of and applications for self-imaging in optical fibers

Experimental results of self-imaging in optical fibers are reported along with an analytical model that explains the observations. Some implications for sensor design are discussed.     

Pitchfork bifurcation and flip-flop operation with a coupled nonlinear system

A ring cavity system consisting of two hybrid Michelson interferometers coupled together with feedback is constructed. This system shows spatial bifurcation and can be utilized as an all-optical flip-flop device. We demonstrate experimentally a flip-flop operation by use of only a positive pulse in this system.     

Shift-invariant interpattern association neural network

A shift-invariant neural network that uses the translation-invariant property of the modulus Fourier spectra with the heteroassociation interpattern association memory is proposed. A binary encoding of a spectral sampling of the training set is used to preserve the main features. Computer simulations and experimental demonstrations are provided that show the shift-invariant property of the proposed optical neural network.     

Substrate-mode holographic polarization-division multi/demultiplexer for optical communications

Based on the diffractive properties of a transmission-type phase volume hologram, a new type of polarization-division multi/demultiplexer for optical communications is presented.     

Object illumination angle measurement in speckle interferometry

Errors in measurement of the object illumination angle affect fringe interpretation accuracies in speckle interferometry. To measure the object illumination angle we propose a method based on the moiré effect. The technique is easy to implement and was found to yield fast and accurate measurements.     

Thermal-stress-induced birefringence in bow-tie optical fibers

Birefringence induced by thermal stress in bow-tie optical fibers is studied in detail by the use of the finite-element method. Results of computer modeling show that a higher degree of birefringence can be obtained with the use of a larger cladding and larger stress-applying zones in the fiber.