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A boost dc-ac inverter is one which is capable of generating in a single stage ac voltage whose peak value can be higher or lower than the given input dc voltage. The major problem with this system is that the closed loop gain parameters kp and ki have to be optimized because these parameters help us to get desired result with better system response by lowering the rise time, settling time, peak overshoot and steady state error. Moreover when they are not optimized load line disturbances arise because of which the stability of output voltage decreases and THD value increases. So to overcome these difficulties bacterial foraging algorithm is being used. [ABSTRACT FROM AUTHOR]

A high performance offline genetic algorithm based three phase boost inverter has been proposed in this work. The digital PI controller makes use of the offline genetic algorithm to improve the performance of the three phase boost inverter. The offline genetic algorithm is used to improve the dynamic response and decrease the content of total harmonic distortion in the three phase boost inverter. The genetic algorithm decreases the effect of the parameters such as rise time, settling time, peak overshoot and steady state error which influence the dynamic response of the system. The overall system efficiency and reliability is shown to be enhanced due to the offline genetic algorithm. The content of total harmonic distortion is also shown to be decreased due to the proposed offline genetic algorithm. [ABSTRACT FROM AUTHOR]

For the reenactment of internet and cloud technologies, interoperability is an important touchstone. Most of the consumers are analyzing the appropriateness of cloud to employ themselves for their enterprise or personalized operations. Customers are self-satisfied at the inception, but expectation changes. Based on their business escalation it needs further adoption of modern cloud services the existing cloud provider fails to offer. Hence the user needs interoperability and portability to ship their assets from one cloud to other cloud. The complication faced by the customers in shifting their assets remains as a challenge to be addressed. In this paper we outline the existing cloud technologies, interoperability issues and possible solution to overcome the problems. [ABSTRACT FROM AUTHOR]

A new generalization of Fiedler's lemma is obtained by introducing the concept of the main function of a matrix. As applications, the universal spectra of the H -join of any graphs (possibly non-regular) and the adjacency spectra of the H -generalized join constrained by (arbitrary) vertex subsets are obtained. The adjacency spectra of the generalized corona of graphs is deduced from the spectra of the H -join of graphs. Also, the construction of infinitely many pairs of non-regular universal cospectral graphs is provided. [ABSTRACT FROM AUTHOR]

• Rule based energy management for hybrid micro grids. • Control strategy for the effective operation of virtual storage units. • Operation of DC non-critical loads as per the voltage produced by the renewable sources. • An attempt to make the hybrid micro grids more autonomous by controlling only the DC non-critical loads. The work presented in this article proposes a new energy management algorithm for hybrid micro grids consisting of higher penetration of DC non-critical (NC) loads and renewable energy sources. The methodology suggested in this work is a rule based approach and tries to make the micro grids more autonomous. During generation deficits in the micro grids, the suggested control strategy proposes to make the hybrid micro grids self-dependent to a possible extent, without the incorporation of actual storage devices. Instead of using actual storage elements like the batteries or super capacitors, the projected approach uses virtual storage devices, like the DC electric springs for its functionality. The electric springs used in this work operate the DC NC loads in accordance with the voltage produced by the renewable sources, which in turn reduces the power import from the main grid during generation deficits in the micro grid. Further, the work presented in the due course only studies about the efficiency of the proposed algorithm by operating the DC NC loads as per the requirement, without intervening with the AC and DC critical loads operation. In order to test the robustness of the proposed methodology a scaled down hybrid micro grid is developed in the laboratory using dSPACE 1104 real time interface. [ABSTRACT FROM AUTHOR]

• Wireless power transformer exhibits a non-linear relation between the coils. • A precise linear functioning region is identified in the wireless power transformer. • No additional sensors required for the transformer realization in a linear region. • Modeled a wireless power transmission system to design the closed-loop controller. • Implemented a linear wireless charger with an efficiency of 93% at 200 mm separation. The transportation field is witnessing a plethora of changes in vehicle electrification sector. One of the revolutionary technologies emerging in this filed is wireless power transmission. Despite various advantages like universal nature, non-physical contact and ease of access, wireless power transmission faces some limitations like flux leakage, non-linear transmitter-receiver relation, etc. This non-linear behavior of wireless power transformer causes a dynamic input-output relation throughout the operation. This leads to the use of multiple sensors which would increase the closed-loop response time. These additional sensing elements and gain determining process will reduce the power transfer efficiency in light power electric vehicles like electric bicycles. To mitigate these non-linear effects of wireless power transmission, a customized linear region is identified and implemented in this work. In this identified region of the transformer, the input-output relation will be linear, which will prevent the use of additional sensing elements. A 250 W electric bicycle is used for this study of linear control of the wireless charger. The overall efficiency of 93% is achieved for a coupling separation of 200 mm even when the primary and secondary coils have much higher misalignments. The linear closed-loop region is designed and represented with analytical equations, and the transformer efficiency obtained through these equations have been validated with the hardware outputs as well as with commercial simulations. [ABSTRACT FROM AUTHOR]

• DPM model used to analyze injection point effect on hydrogen flow field at four locations. • Dense discrete Eulerian Lagrangian simulation used to study MWCNT nanoparticle impact on hydrogen flow field. • Injection point location affects DPM concentrations highest at 0.2 m and lowest at 0.6 m without disturb on dynamic pressure. • MWCNT nanoparticles enhance hydrogen flow velocity through downstream effects, vortices, and nano-enhancement effect. Discrete phase model used in the aerospace industry to stimulate the behavior of particles inside the aircraft engines. The application of the discrete phase modeling (DPM) is extensive in solving the real-time engineering problems in optimization of numerous systems. In the current study, the DPM model has been simulated to examine the effect of injection point on the hydrogen flow field. A domain has been proposed and the injection point has been positioned in the four different places at the regular intervals. The location of the injection points was 0.2 m, 0.3 m, 0.4 m and 0.6 m. Dense discrete Eulerian lagrangian numerical simulation has been employed to analyze the effect of the multi-walled carbon nanotubes (MWCNT) nanoparticles. The hydrogen has been supplied at the injection velocity of 2 m/s. ANSYS implicit simulation setup has been tested across various injection points. The research found that the location of injection points plays a significant role in DPM concentration, with the highest concentration at 0.2 m and the lowest at 0.6 m, but has no significant impact on dynamic pressure. MWCNT nanoparticles had a negligible effect on skin friction coefficient, but shifting the injection point could reduce skin friction rates. The inclusion of MWCNT nanoparticles increased hydrogen flow velocity through downstream effects, vortices, and the nano-enhancement effect. The study suggests that MWCNT can significantly enhance hydrogen flow velocity in various applications, and DPM concentration data can provide valuable insights for optimizing injection locations to prevent unwanted nanoparticle effects. [ABSTRACT FROM AUTHOR]

A PCR-RFLP method was used to identify five species of raw and processed groupers belonging to the genus, Epinephelus viz. E . areolatus , E . bleekeri , E . faveatus , E . longispinis and E . undulosus . DNA extracted from all the species using phenol-chloroform method amplified the mt 16S rRNA gene, unique for the genus, Epinephelus , using GenF and EpiR primers at 300 bp. This fragment did not amplify the DNA of even closely related grouper genus, Cephalopholis , making the method more specific the grouper genus, Epinephelus . The specificity was further ascertained by performing the internal control that targeted 18S rRNA, which was eukaryotic specific. Digestion of PCR products with three selected restriction enzymes viz. SduI , BciVI , and Sau3AI followed by PAGE yielded species specific patterns that enabled identification of three grouper species viz. E . bleekeri , E . faveatus and E . longispinis , while the other two species viz. E . areolatus and E . undulosus gave similar pattern in the gel, although minor variations in the molecular sizes of digested products were noticed. Chilled, frozen and cooked groupers also gave similar PCR-RFLP pattern to that of raw groupers making this method suitable even for processed products. [ABSTRACT FROM AUTHOR]