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The reliable operation of power networks depends on the correct configuration of protection systems. These systems involve the coordination of devices across a wide area, each with numerous setting parameters. Presently, protection settings data are typically stored in various vendor-specific proprietary formats, which are difficult to access, interchange, and manipulate automatically. Consequently, the engineering processes for implementing modern protection systems are extremely complex, involving multiple software tools from different vendors. This paper presents a novel solution to these challenges, through the use of the data model provided by the IEC 61850 standard, with the System Configuration description Language (SCL) format to represent protection settings data. The design of a Protection Setting Conversion Tool (PSCT) that can automatically convert existing settings data between proprietary formats and the SCL-based format is presented. A case study of its implementation demonstrates the benefits of the common representation of protection settings for network operators and other stakeholders. This paper also addresses the challenges that network operators face in migrating to the new approach from existing legacy protection devices and data formats. Adoption of these recommendations and design approaches would shift protection systems from being largely single-vendor solutions to becoming efficient and truly open platforms, capable of supporting future intelligent applications and tools such as automated protection settings validation, diagnostics, and system simulation.

Here we present the first use of intraneural and intrafascicular infrared neural stimulation (INS) with early-generation Utah Slanted Optrode Arrays (USOAs) to produce highly selective, artifact-free stimulation of peripheral nerves. USOAs utilize technology previously developed for Utah Slanted Electrode Arrays, and contain 100 silicon optrodes of 0.5 to 1.5 mm length, spaced 400 m apart in a 10 x 10 grid. The optrodes penetrate into the nerve and closely abut nerve fibers, thus providing multiple, independent, focal sites of stimulation. We first demonstrated that intraneural (but extrafascicular) infrared (IR) stimulation of cat sciatic nerve with conventional optical fibers coupled to a Lockheed Martin Aculight Capella laser produced stronger and more selective neural and muscle compound action potentials (CAPs) than did extraneural INS. We next tested INS through individual USOA optrodes (e.g., wavelength 1873 nm, 5- ms stimulus pulse, < 1 mJ at optrode tip). In contrast to extraneural INS, intrafascicular INS evoked relatively strong and highly selective, optrode-specific responses. Further, there were no observable stimulus artifacts, thereby allowing adjacent electrical recordings. These initial results indicate that intrafascicular INS via USOAs may provide a more efficient, more selective, high-optrode-count means of activating axons, plus greater access to interior nerve fibers.

The effect of the pulse width of a pulsed laser in the studies of speckle velocimetry and transient vibration analysis is discussed. Because of the motion of the object during an exposure, a sine function is obtained by using the pointwise filtering method. This function modulates the halo along with the Young’s fringes. It is shown that for high object velocities the sinc function modifies the halo distribution; as a result, the error in calculating the fringe position increases. An aperture geometry for which the autocorrelation halo is made constant in certain regions is proposed in which the intensity variation in this region is the result of the modulating sinc function only. A closed-form solution for the shift in the position of the fringes in this region is obtained. Experimental results of the simulation are presented.