24 research outputs found

    Electrical Discharge Coating a Potential Surface Engineering Technique: A State of the Art

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    Electrical discharge coating (EDC) process is used to deposit material on workpiece surface from sacrificial or green compact tool electrode in an electrical discharge machine. The paper presents the mechanism of EDC using green compact electrode and powder mixed dielectric methods. The tool electrode material, electrode size, process parameters, and type of dielectrics can directly affect the surface integrity of workpiece. Here, a process map of EDC as a function of process parameters, its classification, advantages, and applications for a wide range of engineering materials offers a proper template for the evaluation of coating phenomena. This study shows that EDC is an economic process as compared to other costlier techniques. Additionally, the effect of various EDM and EDC parameters on surface integrity and tribological behavior of deposited coatings is studied with their pros and cons. Finally, the current research trends of EDC and its challenges are elaborated.info:eu-repo/semantics/publishedVersio

    Whale Optimization for MPPT of Single Stage Grid Integrated PV Plant with H∞ and TSK-Fuzzy Controllers

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    Numerous techniques for maximum power point tracking (MPPT) are extensively employed to extract the utmost energy from Photovoltaic (PV) panels. The P&O method is a highly effective technique among those who perturb and observe. Nevertheless, in the presence of partial shading conditions, it becomes imperative to employ an optimization algorithm that can accurately pinpoint the global maximum location (GML) amidst the numerous local maximum locations. The Whale-inspired algorithm is a renowned optimization method for efficiently identifying GML in comparison to numerous other optimization algorithms. An inverter is required to interfacing between PV and grid in single stage grid connected system as it will also work as a MPPT device by controlling voltage corresponding to GML. In this situation, the utilization of a whale-inspired optimization technique can enhance energy harvesting through an appropriate inverter controller. The combination of TS-Fuzzy and H∞ controllers through hybridization can lead to rapid response times and increased system stability. Hence, this paper introduces a new controller designed for the inverter to function effectively in a single-stage grid-connected PV system. The proposed controller can also provide the grid with high-quality power. This work showcases comprehensive findings derived from Hardware-in-the-Loop (HIL) testing conducted using OPAL-RT technologies

    Five-Level DSTATCOM for Power Quality Improvement Using Intelligent Controllers

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    Addressing power quality issues is an important task for power engineers as a small disturbance in power system can initiate hefty disaster to the loads connected at user point. FACTS controllers are latest devices which can improve power system stability in case of voltage sag/swell and presence of harmonics. DSTATCOM in distribution system is one of the fine FACTS controllers which can address power quality issues. DSTATCOM is a voltage source converter connected at PCC delivering a three-level output. This 3- level output consists of harmonics which insists for high sized filters increasing system cost. This paper depicts five-level DSTATCOM connected to distribution system delivering qualified output reducing amount of harmonics which excludes high sized filters improving system efficiency and making system economic. PQ theory was employed to drive DSTATCOM. Fuzzy technique in PQ theory of controlling five-level DSTATCOM is presented in this paper comparing with conventional PI controller performance of reducing harmonics in distribution system

    Physical characters and economics of acrylic and epoxy polymers as frame components of external skeletal fixator

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    Physical characters of acrylic and epoxy polymers used in constructing external skeletal fixator vis-à-vis economics were compared in the present study. The fixator constructs were prepared using acrylic/epoxy polymer, 1.5 mm K-wires and ultra high density polyethylene rods as a bone substitute. Observations on fabrication ease, weight, radiographic properties and economics of polymers were taken. The epoxy polymer being doughy, less heat producing and fumeless was easier to fabricate into constructs. Hardening time for acrylic was dependent on environmental temperature with an average of 11 min; whereas, epoxy putty hardened in about 22 min and the hardening was independent of environmental temperature. Acrylic fixators were radiolucent and significantly lower in weight. Preparation cost of epoxy constructs was significantly lower than acrylic constructs. Present study provides baseline benchmarks to choose polymers in constructing external skeletal fixators according to available resources, technical expertise and economics involved

    Primary sclerosing encapsulating peritonitis

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    Sclerosing encapsulating peritonitis also known as cocoon abdomen is a rare chronic inflammatory condition of the peritoneum in which the bowel loops are encircled by a membrane (cocoon formation) within the peritoneal cavity leading to intestinal obstruction. It can be primary (idiopathic) or secondary (chemotherapy, beta-blockers, peritoneal dialysis, shunts, tuberculosis, systemic lupus erythematosus, etc.). The symptomatology report includes recurrent episodes of abdominal pain and vomiting. We present here a case of a 32-year-old male who presented with complaints of being unable to pass stools, vomiting (3–4 times), and abdomen pain for 4 days. This case is considered worth mentioning due to its rarity, lack of identification of secondary causes, and diminutive mention of histopathological aspect

    Glaucoma drainage devices

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    Glaucoma drainage devices (GDD) occupy an important place in the surgical management of glaucoma that is not responding to medications and trabeculectomy operations. In certain conditions, such as neovascular glaucoma, pediatric glaucoma, iridocorneal endothelial syndrome, penetrating keratoplasty with glaucoma, glaucoma following retinal detachment surgery, it has become the preferred operation. GDD create an alternate aqueous pathway from anterior chamber by channeling aqueous out of the eye through a tube to subconjunctival space. Glaucoma drainage implants that have been used extensively include the non-restrictive and restrictive drainage devices. This article outlines history of implants, types of implant, surgical technique of implantation, various complications following GDD insertion and their management

    Effects of electroless nickel -coating on tribological and corrosion behaviour of TMT steel rebar with multi-walled carbon-nanotube and titanium dioxide nanoparticles

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    This study incorporated Multi-walled carbon nanotube particles (MWCNTs) and Titanium Dioxide Nanoparticles (TiO2) into a metal matrix composite in Ni–P coated substrate using an Electroless technique. This study significantly improves the tribological properties, enhances corrosion resistance, increases durability and extends the service life of coated rebar. Coated rebar helps make infrastructure more sustainable by extending the life of buildings and lowering their material consumption, trash output, and ecological footprint. The tribological behaviour of steel rebar has been studied by using a variety of characterization techniques, like X-ray diffraction, Atomic Force Microscopy, Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (EDX) including the corrosion test and the hardness test. The topographical roughness of the bare specimen, Ni–P coated specimen, CNT coated specimen and TiO2 coated specimen are 67.4 nm, 112 nm, 201 nm, and 162 nm respectively. The microhardness of the bare substrate, Ni–P coated, CNT doped coated, and TiO2 dopped coated specimens was done using Vicker's Hardness tester and the mean values were 455 HV, 580 HV, 810 HV, and 680 HV respectively. Resistance to corrosion of TMT steel rebar of Fe500 was examined using the polarisation method and Electrochemical-Impedance-Spectroscope (EIS) method. These techniques were examined in 3.5 wt% aqueous medium of NaCl and analysed the Ecorr (corrosion potential) and Icorr (Corrosion current density) of the bare substrate, Ni–P coated, Ni–P/CNT and Ni–P/TiO2 substrate. The corrosion inhabitation efficiency of the Ni–P-CNT doped was 22.5% more than the Bare substrate, and the TiO2 doped coated specimen was 10.63% more than the bare substrate. Resistance to corrosion of the CNT-coated substrate is better than Ni–P/TiO2 and Ni–P-coated specimens

    Inheritance and identification of molecular markers associated with spot blotch (Cochliobolus sativus L.) resistance through microsatellites analysis in barley

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    Spot blotch resistant (IBON 18) and susceptible (RD 2508) lines were crossed to investigate inheritance of resistance and to identify simple sequence repeats (SSRs) associated with resistance. F1 resistance was intermediate and suggested additive nature of inheritance. Three additive genes was noted in the distribution of F3, F4 and F5 generations. In F6 and F6-7, the quantitative and qualitative approaches also suggested the control of three resistance genes. The parents and the RILs (F6/F6-7) were grown in four environments and spot blotch severity recorded. Forty five SSR primers, specific for chromosomes 1 (7H) and 5 (1H), were applied. Of these, 12 were polymorphic between the parents, and between the resistant and susceptible bulks. Three markers BMS 32, BMS 90 and HVCMA showed association with resistance, which was further confirmed through selective genotyping. The co-segregation data on the molecular markers (BMS 32, BMS 90 and HVCMA) and spot blotch severity on 173 RILs was analyzed by single marker linear regression approach. Significant regression suggested linkage among BMS 32, BMS 90 and HVCMA and the three resistant genes (designated as Rcs-qtl-5H-1, Rcs-qtl-5H-2 and Rcs-qtl-1H-1.) respectively. These markers explained 28%, 19% and 12% of variation respectively, for spot blotch resistance among the RILs
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