28 research outputs found

    A Savonius Wind Turbine with Electric Generator: Model and Test

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    The overall goal of this research is to study the performance of Savonius wind tur-bine. Some of the advantages of a Savonius wind turbine include simple construction, good startup characteristics, low noise, and reduced wear. The applications of this type of wind machine include water pumping and small scale electricity generation. In the present re-search, an experimental model of the Savonius wind turbine is studied including the for-mulation of a mathematical model. The mathematic model for the torque acting on the Savonius rotor has been developed and the permanent magnet synchronous generator (PMSG) model has been simulated using the d-q synchronous reference frame theory. In the present research, the mathematic model of the wind turbine system has been simulated in MATLAB/Simulink environment. The model includes the wind turbine model and the permanent magnet synchronous generator (PMSG) model. The wind turbine pa-rameters of the experimental system have been used for the simulation purpose. A 1kW PMSG has been coupled with the wind turbine to study the dynamic performance of the wind turbine system. The system response and performance have been evaluated at 3 dif-ferent wind speeds of 16.9 m/sec, 19.8 m/sec, and 21.9 m/sec corresponding to the wind speeds of the blower used for experimental system. The experimental Savonius wind turbine has been developed to compare the nu-merical and experimental results. The experimental system includes Savonius rotor, PMSG, charge controller and rectifier, current and voltage transducers, frequency to analog converters, electrical load, and a National Instruments Data Acquisition Device (NI DAQ). The current and voltage transducers are used to measure the current and voltage in the system and the outputs are connected to the NI DAQ. The frequency to analog converters are used to measure the rpm of the rotor and the anemometer. The charge controller is meant for battery charging applications of the system. The numerical and experimental results have been obtained at three different wind speeds (16.9 m/sec, 19.8 m/sec, and 21.9 m/sec). The maximum value of the electric power generated is 2.7 Watts at a wind speed of 21.9 m/sec. Comparison of experimental and numerical results at the wind speed of 21.9 m/sec shows there is an approximate difference of 16%, 11%, 61% and 4% for the angular velocity, voltage, current, and electrical power generated, respectively. The difference in the values may be attributed to the fact that the mathematical model does not include the three-dimensional (3D) fluid effects and environ-mental factors

    Usporedba lidokaina i kombinacije lidokaina i ketamina primijenjenih za distalnu intravensku regionalnu anesteziju (DIVRA) u goveda

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    The hoof diseases of cattle can be managed surgically under intravenous regional anesthesia (IVRA). For routine induction of IVRA, a tourniquet is placed circumferentially at the metacarpus/metatarsus. In the present study, hoof diseases of cattle were corrected using a modified IVRA technique. The cattle with hoof ailments were randomly divided into two groups and a tourniquet was placed just distal to the dew claws instead of at the metacarpus/metatarsus in order to decrease the dose of anesthetic. In group I lidocaine (2mg/kg) and in group II a mixture of lidocaine and ketamine (2mg/kg+1.5mg/kg) was injected into the axial digital vein to induce distal intravenous regional anesthesia (DIVRA). The heart rate, respiration rate, systolic and diastolic pressure were unaffected in both groups. Oxygen saturation was significantly (P<0.05) lower between 5 and 60 minutes in group I and between 15 and 40 minutes in group II animals. The sensory and motor block onset time was shorter, and the sensory and motor block recovery time was longer in group II animals as compared to group I animals. It was concluded that the DIVRA technique using lidocaine alone and lidocaine admixed with ketamine are suitable for hoof examination and surgery.Bolesti papaka u goveda mogu se kirurški liječiti pod intravenskom regionalnom anestezijom (IVRA). Za rutinsko uvođenje u IVRA-u postavlja se kružno čvrsti zavoj na metakarpus/metatarzus. U ovom su istraživanju bolesti papaka u goveda liječene modificiranom IVRA metodom. Istražene životinje nasumično su podijeljene u dvije skupine a zavoj kojim se samnjuje doza anestetika postavljen je, umjesto na metakarpus/metatarzus, distalno od rudimentiranih papaka. U skupini I primijenjen je lidokain (2 mg/kg), a u skupini II kombinacija lidokaina i ketamina (2 mg/kg + 1,5 mg/kg). Za uvođenje u distalnu intravensku regionalnu anesteziju (DIVRA) anestetici su aplicirani u aksijalnu digitalnu venu. Srčana frekvencija, frekvencija disanja, sistolički i dijastolički tlak u obje su skupine bili nepromijenjeni. Zasićenost kisikom bila je znakovito niža (P<0,05) između 5. i 60. minute u skupini I te između 15. i 40. minute u skupini II. Vrijeme pojave senzornih i motoričkih blokova bilo je kraće, a vrijeme oporavka tih blokova dulje u životinja u skupini II u usporedbi sa skupinom I. Zaključeno je da je DIVRA, uz upotrebu i samog lidokaina i lidokaina u kombinaciji s ketaminom, prikladna metoda za pregled i obavljanje kiruških zahvata na papcima goveda

    India after the 2014 general elections:BJP dominance and the crisis of the third party system

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    This article critically assesses claims that India has entered a new party system after the 2014 general elections, marked by renationalisation with the BJP as the new 'dominant' party.' To assess these claims, we examine the electoral rise of the BJP in the build-up to and since the 2014 general elections until the state assembly elections in December 2018. Overall, we argue that despite the emerging dominance of the BJP, a core feature of the third party system -a system of binodal interactions- has remained largely intact albeit in a somewhat weaker form. Furthermore, by comparing the post 2014 Indian party system with key electoral features of the first three party systems, we conclude that the rise of the BJP has thrown the third-party system into crisis, but does not yet define the consolidation of a new party system

    Microwave assisted transformation of benzimidazolyl chalcones into N<sup>1</sup>-substituted pyrazolines and evaluation of their antimicrobial activities

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    989-9931-Benzimidazolyl-3-aryl-prop-2-ene-1-ones 2 have been transformed into N1-substituted pyrazoline derivatives by the interaction with phenyl hydrazine, thiosemicarbazide and hydrazine hydrate in the presence of formic acid under solvent free microwave induced protocol. The structure of newly synthesized compounds have been confirmed on the basis of their elemental analysis and spectral data. Newly synthesized compounds have been evaluated for their antimicrobial activity in vitro against E. coli, K. pneumonae, P. aeruginosa and B. subtilis using paper disc method. Some of the compounds have shown significant activity against the pathogens

    Dual-Sided Involvement of Energy Optimization and Strategic Bidding in Wind-PV System to Maximize Benefits for Customers and Power Providers

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    Global warming is causing industrial development to increase greenhouse gas emissions, impact power provider economies, and potentially pose a solution through renewable energy. In order to solve these issues, the research offers a dual strategic auction difficulty for renewable energy market clear prices (MCPs) to maximize supplier and buyer revenues while mitigating rival unpredictability and renewable vacillation power supply sources. The study uses scenario reduction techniques, including Beta and Weibull distribution of probability, forward-reduction technique, and underestimation and overestimation of the cost function to manage uncertainties in renewable energy. The Gravitation Search algorithm and a hybrid approach ordered weighted average distance (OWAD) combined, with Topsis operational gravitational search algorithm TOGSA (OWAD-TOGSA), are used to solve the multi-objective issue. The study evaluates the performance of IEEE standard 30-bus and 57-bus test systems and an Indian 75-bus operational system to solve a problem involving wind and sun energy in spite of its volatility. The proposed bidding approach is feasible and could increase revenue by nearly 10 &#x0025;, potentially improving efficiency for electric energy-producing utilities and consumers, and its findings will be beneficial for similar research using optimization techniques

    Role of Inferior Vena Cava (IVC) Recanalization in Patients with Back Pain, Secondary to IVC Obstruction in Budd–Chiari Syndrome

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    Purpose: To study the prevalence of back pain in patients of Budd–Chiari syndrome (BCS) with inferior vena cava (IVC) obstruction, and to evaluate the role of IVC recanalization in resolution of back pain. Methods: All patients with BCS and IVC obstruction who underwent IVC recanalization between January 2018 and October 2022 were included. Patients with degenerative spine disease or other identifiable causes for back pain were excluded; remaining patients were assessed for the presence of back pain. In patients with back pain, pain relief was assessed at 24 h following IVC recanalization. Results: Fifty-eight patients with BCS and IVC occlusion were identified, of which six with degenerative spine diseases were excluded. Of the remaining 52 patients, 34 (65.4%) had back pain, with pain score between 3 and 9. Engorged epidural venous plexus on preprocedural imaging (p = 0.002), and degree of luminal narrowing (p = 0.021) had a significant association with back pain. Twenty-nine of thirty-four patients (85.3%) with back pain had pain relief immediately following IVC recanalization, more so in patients with engorged epidural venous plexus on preprocedural imaging (p < 0.001). Conclusion: Back pain is one of the under-reported symptoms of IVC obstruction in BCS. IVC recanalization by IVC angioplasty with or without stenting relieves back pain due to the decompression of engorged epidural veins
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