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The present work describes a model simulation study of electrowetting on a dielectric surface (EWOD)-based liquid lens using three distinct insulating liquids, namely, silicone oil, n-hexadecane, and n-tetradecane. The model essentially consists of a cylindrical chamber with a typical inner diameter of 3.0 mm and a height of 1.0 mm coated with two different hydrophobic dielectric surfaces, pyrelene-Cand teflon- AF. With a 21.4 mM KCl solution employed as a conducting liquid, the interfacial layer between the two immiscible liquids was found to be modulated precisely for a critical biasing voltage, V> 90 V, switching the curvature profile from diverging to converging type. Moreover, the effects of applied voltage and dielectric layer thickness on this changeover and focal lengths were discussed for a given set of aforesaid pairs of immiscible liquids. Our simulated results and model analyses provide useful insights on the means of experimental strategies, scope, and limitations towards realization of industrial-grade designs and assets.

In this paper, a detailed study of the modes of hidden failures (HFs) in protection systems is carried out, and probabilistic modeling methodology is used for analyzing the impact of HFs on the power system cascading events. Further, the probabilistic model of HFs based on impedance and line power flow is hypothesized for qualitative evaluation of HF’s impact on power system cascading disruptions. Numerous case studies have been carried out on the IEEE-118 bus system to assess the effect of HFs by fitting the probability model of line outage based on impedance and power flow. This analysis has successfully identified the most sensitive transmission lines in the network which are having the highest tendency to trip in case of protective system HFs. Also, it has been shown that the probability of major blackouts will be reduced to a more significant extent if the self-checking and monitoring features are incorporated into digital relays. The qualitative analysis of protection system HFs could be helpful in planning, service and maintenance scheduling of a power system as well as determining the locations where an investment warrants the protection system reliability.

Maloperation of conventional relays is becoming prevalent due to ever increase in complexity of conventional power grids. They are dominant during power system contingencies like power swing, load encroachment, voltage instability, unbalanced loading, etc. In these situations, adaptive supervised wide-area backup protection (ASWABP) plays a major role in enhancing the power system reliability. A balance between security and dependability of protection is essential to maintain the reliability. This paper proposes multi-phasor measurement units (MPMU) based ASWABP scheme that can function effectively during faults besides power system contingencies. MPMU is an extended version of Phasor Measurement Unit (PMU). It is an intelligent electronic device which estimates the synchronized predominant harmonic phasors (100Hz and 150Hz) along with the fundamental phasors (50Hz) of three phase voltages and currents with high precision. The proposed ASWABP scheme can detect the fault, identify the parent bus, determine the faulty branch and classify the faults using MPMU measurements at System Protection Center (SPC). Based on these MPMU measurements (received at phasor data concentrator (PDC) at SPC) the appropriate relays will be supervised to enhance the overall reliability of the power grid. Numerous case studies are conducted on WSCC-9 bus and IEEE-14 bus systems to illustrate the security and dependability attributes of proposed ASWABP scheme in MATLAB/Simulink environment. Also, comparative studies are performed with the existing conventional distance protection (Mho relays) for corroborating the superiority of the proposed scheme regarding security and dependability. Comparative studies have shown that the proposed scheme can be used as adaptive supervised wide-area backup protection of conventional distance protection.

Assessment of software reliability is an area of the utmost importance for software-based systems employed in safety-critical applications such as computer relaying of power transmission lines. In a typical software development process, software is designed as a combination of components and modules instead of a monolithic block. Different components contribute to varying degrees to the overall functioning of software and thus knowledge of component importance can reveal vital information for software designers and test engineers. Moreover, software reliability is estimated on the basis of collected historical data followed by an assumed distribution curve and is thus inherently susceptible to uncertainties. The fault tree is an important aid that is used widely for safety and reliability consideration of component-based systems and can also be applied to software. In fault tree analysis, the uncertainties in the failure probability of a system's basic component can be propagated to find the uncertainty of the overall system. Fuzzy set theory has been used in fault tree analysis for quantifying the basic event uncertainty and for propagating it. In this paper, a methodology to assess fuzzy module importance as well as fuzzy module uncertainty importance of software has been presented. A case study of computer relay software has been used to demonstrate the viability of the proposed methodology.

In this work, we present surfactantcetyltrimethyl ammonium bromide, CTAB assisted solidstate fabrication and characterization of hydroxylfree ZnO and Tbdoped ZnO nanorods. 80MeV nitrogen ion irradiation fluence: upto 8 × 1012 ionscm2 was performed to explore irradiationinduced modification in the structural and optical properties of the nanorods. In the asymmetrically broadened photoluminescence PL spectra of the irradiated samples, the bandedge emission ∼370 nm is found to be suppressed due to the dominance of the defect related emissions. Apart from ZnOdefectrelated emissions within 405–535 nm due to zincoxygen vacancies, interstitial etc., we have adequately identified the Tbrelated 5D4–7F6and 5D4–7F5transitions at ∼490 and 548 nm, respectively. At the highest fluence 8 × 1012 ionscm2, the nanorod structural ordering is lost, which is characterized by a luminescence quenching. The nitrogen irradiation at the chosen energyfluence, and selective Tbrelated transitions are promising for precise control over tunability in the specific luminescence patterns of interest.

Abstract: ZnS:Mn nanoparticles of size variation 11–17 nm were synthesized by a simple and inexpensive chemical method and confirmed by transmission electron microscopy (TEM). Presuming electronic energy loss (S e>S n, S n being nuclear energy loss) to be the dominant phenomenon, they were irradiated by 80-MeV energetic oxygen ions with fluence of 1011 to 1013 ions/cm2. Photoluminescence (PL) spectra revealed three major emission bands ~445 nm, ~582 nm and ~706 nm; which are ascribed to D–A pair transition, Mn emission and surface state led fluorescence activation. The recovery of Mn emission and tunable surface state emission have been observed with ion fluence variation. Infra-red (IR) spectra of irradiated samples show great extent of oscillation with respect to amplitude due to ion fluence variation however, phonon energy (~98 MeV) remains unchanged. The possible applications of these modified properties in nanophotonics are also highlighted.

Manganese-doped cadmium sulfide nanoparticles are synthesized in a flexible polymer matrix (synthetic rubber) by a chemical route. They are bombarded with 80-MeV oxygen ions having electronic energy loss (Se) dominant over nuclear energy loss (Sn) and with fluence variation 1011?1013 ions/cm2. Piling up of nanoparticles along certain direction was observed in atomic force microscopy (AFM) images of irradiated samples. Such elongated nanostructures are as a result of nanoparticle growth during ion passage through the samples. Specifically, elongated structures in the form of nanoneedles, nanochannels and nanorods have been observed. The fluence dependent photoluminescence spectra (PL) show significant luminescent peaks at 445 nm and 706 nm, respectively which are tunable with ion fluence. Such a tunability could be promising as lasing materials in nano-luminescent devices and laser diodes. Further, detection of efficient third harmonic generation (THG) in these samples (by using irradiation of a Cr:fosterite laser) could be promising in nanoscopy and nonlinear optics.

Manganese-doped cadmium sulfide nanoparticles are synthesized in a flexible polymer matrix (synthetic rubber) by a chemical route. They are bombarded with 80-MeV oxygen ions having electronic energy loss (Se) dominant over nuclear energy loss (Sn) and with fluence variation 1011–1013ions/cm2. Piling up of nanoparticles along certain direction was observed in atomic force microscopy (AFM) images of irradiated samples. Such elongated nanostructures are as a result of nanoparticle growth during ion passage through the samples. Specifically, elongated structures in the form of nanoneedles, nanochannels and nanorods have been observed. The fluence dependent photoluminescence spectra (PL) show significant luminescent peaks at 445 nm and 706 nm, respectively which are tunable with ion fluence. Such a tunability could be promising as lasing materials in nano-luminescent devices and laser diodes. Further, detection of efficient third harmonic generation (THG) in these samples (by using irradiation of a Cr:fosterite laser) could be promising in nanoscopy and nonlinear optics.

Manganese doped zinc sulfide nanoparticles are fabricated on polyvinyl alcohol dielectric matrix. They are bombarded with energetic chlorine ions (100 MeV). The size of the crystallites is found to increase with ion fluence due to melting led grain growth under ion irradiation. The increased size as a result of grain growth has been observed both in the optical absorption spectra in terms of redshift and in electron microscopic images. The photoluminescence (PL) study was carried out by band to band excitation (λex= 220 nm) upon ZnS : Mn, which results into two emission peaks corresponding to surface states and Mn+2emission, respectively. The ion fluence for irradiation experiment so chosen were 1 × 1011, 5 × 1011, 5 × 1012and 1013Cl/cm2.

Continuous monitoring and control of the power system is essential for its healthy operation. This can be achieved by making the system observable as well as controllable. Many efforts have been made by several researchers to make the system observable by placing the Phasor Measurement Units (PMUs) at the optimal locations. But so far the idea of controllability with PMUs is not considered. This paper contributes how to check whether the system is controllable or not, if not then how make it controllable using a clustering approach. IEEE 14 bus system is considered to illustrate the concept of controllability.