Coordination of PV Inverters and Voltage Regulators Considering Generation Correlation and Voltage Quality Constraints for Loss Minimization

Abstract

Distributed generation sources (DGs) are widely considered as important sources of power generation in distribution systems during the last few decades. Despite the substantial benefits of DGs, increasing the penetration level of the DGs can cause dramatic voltage magnitude fluctuations. Coordination of the use of dynamic reactive power sources such as photovoltaic (PV) inverters and voltage control equipment can mitigate rapid voltage magnitude fluctuations. A coordinated volt-var control method is proposed herein to achieve the optimal expected performance (e.g., system losses) while considering the spatial correlation among PV source powers and constraining the variability of voltage magnitudes throughout the distribution network within permissible ranges. The proposed strategy formulates chance constraints on the voltage magnitude and considers the uncertainty of PV power injections over the interval of interest to maintain voltage magnitudes within acceptable limits. The proposed method has been tested on the IEEE 123-node radial distribution system for validation. Moreover, the simulation results demonstrate that the proposed method can effectively mitigate the fast voltage magnitude deviations with an acceptable reduction in system losses in the presence of intermittent renewable resources.     

Intensive Data Management in Parallel Systems: A Survey

In this paper we identify and discuss issues that are relevant to the design and usage of databases handling massive amounts of data in parallel environments. The issues that are tackled include the placement of the data in the memory, file systems, concurrent access to data, effects on query processing, and the implications of specific machine architectures. Since not all parameters are tractable in rigorous analysis, results of performance and bench-marking studies are highlighted for several systems.     

An overview on marine anti-allergic active substances for alleviating food-induced allergy

Abstract

Food provides energy and various nutrients and is the most important substance for the survival of living beings. However, for allergic people, certain foods cause strong reactions, and sometimes even cause shock or death. Food allergy has been recognized by the World Health Organization (WHO) as a major global food safety issue which affect the quality of life of nearly 5% of adults and 8% of children, and the incidence continues to rise but there is no effective cure. Drug alleviation methods for food allergies often have shortcomings such as side effects, poor safety, and high cost. At present, domestic and foreign scientists have turned to research and develop various new, safe and efficient natural sources of hypoallergenic or anti-allergic drugs or foods. There are many kinds of anti-allergic substances obtained from the plants and animals have been reported. Besides, probiotics and bifidobacteria also have certain anti-allergic effects. Of all the sources of anti-allergic substances, the ocean is rich in effective active substances due to its remarkable biodiversity and extremely complex living environment, and plays a huge role in the field of anti-food allergy. In this paper, the anti-food allergic bioactive substances isolated from marine organisms encompassing marine microbial, plant, animal sources and their mechanism were reviewed and the possible targets of anti-allergic substances exerting effects are illustrated by drawing. In addition, the development prospects of marine anti-allergic market are discussed and forecasted, which can provide reference for future research on anti-allergic substances.     

Parametric optimization in wire electric discharge machining of DC53 steel using gamma phase coated wire

DC53 is considered as superior steel grade by die and mold making industries as compared to D2 and D3 steel due to its excellent mechanical characteristics     

An AI-based Approach for Improved Sign Language Recognition using Multiple Videos

Multimedia Tools and Applications - People with hearing and speaking disabilities face significant hurdles in communication. The knowledge of sign language can help mitigate these hurdles, but most...     

Seed Layer-Assisted Chemical Bath Deposition of Cu2O Nanoparticles on ITO-Coated Glass Substrates with Tunable Morphology,Crystallinity, and Optical Properties

A seed layer-assisted chemical bath deposition method performed at low temperature has been developed to grow uniform and high-quality crystal cuprous oxide (Cu₂O) nanoparticles on transparent conductive/glass substrates. The annealing process by continuous beam (CW) of CO₂ laser was used prior to growing the Cu₂O nanoparticles. In this study, the controlled synthesis of Cu₂O films was investigated by controlling the growth temperatures at 55 °C, 60 °C, 65 °C, and 70 °C, respectively. The modified seeding substrate reflect enhanced structural properties with laser annealing temperature of 450 ℃. In addition, Cu₂O nanoparticles with flower-like stricter show a greater density containing a smaller particle with 75 nm average dimension and flower particle size was about 85 nm. Results suggest an effective synthesis route for developing high-quality Cu₂O nanoparticles for optical and electronic applications.

     

DETERMINATION OF SEVERAL PHYSICAL PROPERTIES OF LIGHT PETROLEUM PRODUCTS USING IR

ABSTRACT

In the present study IR spectrometric analysis was used to determine clear research octane number, heat of formation, specific gravity and mole fraction of methyl group, simultaneously in hydrocarbon mixtures. IR absorption spectrum can be used to provide information, that can be obtained by several existing test methods.     

A new strategy for the synthesis of polyaniline nanostructures using m-CPBA as an oxidant

In this work, we have reported a unique strategy of using Meta-Chloroperoxybenzoic acid (m-CPBA) as an oxidant for Polyaniline (PANI) nanofibers preparation. A templateless rapid mixing method was employed for chemical polymerization of aniline at room temperature under rapid mixing and without use of additional oxidant. PANI nanofibers were fully characterized and their electrochemical properties have been studied in detail. Further, effects of toluene solution on PANI electrochemical properties were also investigated in detail. The results showed that PANI nanofibers, in the presence of toluene as solvent, had relatively high specific capacitance and high columbic efficiency compared to their bulk solution, which was due to the immobile of toluene solution and the fast diffusion of the H⁺ ions through the polymer material during the redox process.