Design of LLC resonant converter with silicon carbide MOSFET switches and nonlinear adaptive sliding controller for brushless DC motor system

Introduction. The high voltage gain DC-DC converters are increasingly used in many power electronics application systems, due to their benefits of increased voltage output, reduced noise contents, uninterrupted power supply, and ensured system reliability. Most of the existing works are highly concentrated on developing the high voltage DC-DC converter and controller topologies for goal improving the steady state response of brushless DC motor driving system and also obtain the regulated voltage with increased power density and reduced harmonics, the LLC resonant DC-DC converter is implemented with the silicon carbide MOSFET switching devices Problem. Yet, it facing the major problems of increased switching loss, conduction loss, error outputs, time consumption, and reduced efficiency. Also the existing works are mainly concentrating on improving the voltage gain, regulation, and operating performance of the power system with reduced loss of factors by using the different types of converters and controlling techniques. The goal of this work is to obtain the improved voltage gain output with reduced loss factors and harmonic distortions. Method. Because, this type of converter has the ability to generate the high gain DC output voltage fed to the brushless DC motor with reduced harmonics and loss factors. Also, the nonlinear adaptive sliding controller is implemented to generate the controlling pulses for triggering the switching components properly. For this operation, the best gain parameters are selected based on the duty cycle, feedback DC voltage and current, and gain of silicon carbide MOSFET. By using this, the controlling signals are generated and given to the converter, which helps to control the brushless DC motor with steady state error. Practical value. The simulation results of the proposed LLC silicon carbide MOSFET incorporated with nonlinear adaptive sliding controller controlling scheme are validated and compared by using various evaluation indicators. Вступ. Високовольтні перетворювачі постійного струму з високим коефіцієнтом посилення напруги все частіше використовуються в багатьох прикладних системах силової електроніки через їх переваги, пов'язані з підвищеною вихідною напругою, зниженим рівнем шуму, безперебійним живленням і гарантованою надійністю системи. Більшість існуючих робіт значною мірою зосереджені на розробці топологій високовольтного перетворювача постійного струму і контролера з метою поліпшення усталеного відгуку системи приводу безщіткового двигуна постійного струму, а також отримання регульованої напруги з підвищеною щільністю потужності і зменшеними гармоніками; резонансний LLC-перетворювач постійного струму, реалізований на перемикаючих пристроях на основі польових МОП-транзисторах з карбіду кремнію. Проблема. Тим не менш, це стикається з основними проблемами, пов'язаними зі збільшенням втрат при перемиканні, втратами провідності, помилками на виході, витратами часу та зниженням ефективності. Крім того, існуючі роботи в основному зосереджені на покращенні коефіцієнта посилення напруги, регулювання та робочих характеристик енергосистеми із зменшенням факторів втрат за рахунок використання різних типів перетворювачів та методів управління. Метою роботи є отримання покращеного коефіцієнта посилення напруги зі зниженими коефіцієнтами втрат і гармонійних спотворень. Метод. Таким чином, цей тип перетворювача здатний генерувати вихідну постійну напругу з високим коефіцієнтом посилення, що подається на безщітковий двигун постійного струму, зі зменшеними коефіцієнтами гармонік та втрат. Крім того, реалізований нелінійний адаптивний ковзний регулятор для генерування керуючих імпульсів для належного спрацьовування перемикаючих компонентів. Для цієї операції вибираються найкращі параметри посилення на основі робочого циклу, постійної напруги та струму зворотного зв'язку, а також коефіцієнта посилення польового МОП-транзистора з карбіду кремнію. При цьому керуючі сигнали генеруються і передаються на перетворювач, який допомагає керувати безщітковим двигуном постійного струму з помилкою, що встановилася. Практична цінність. Результати моделювання запропонованого LLC-перетворювача на основі польових МОП-транзисторів з карбіду кремнію зі схемою управління нелінійним адаптивним ковзним регулятором перевіряються та порівнюються з використанням різних показників оцінки.&nbsp

Survival of Azospirillum brasilense in liquid formulation amended with different chemical additives

Liquid bioinoculant formulation has become the preferred technology to solve the problems associated with shorter shelf life, high contamination, poor quality, low field performance and processing solid carrier in carrier based bioinoculant formulation.  In this experiment, we evaluated different concentrations of six different chemical amendments viz, polyvinyl pyrollidone (PVP), glycerol, gum arabica, trehalose, polyethylene glycol (PEG) and polyvinyl alcohol (PVA) for their ability to support growth and promote survival of Azospirillum brasilense in N2 free malic acid broth during the storage. Some concentrations of various additives to N2 free malic acid broth promoted higher Azospirillum population compared to Azospirillum cells in N2-free malic acid broth alone. Liquid Azospirillum bioinoculant formulated with trehalose (10mM) promoted long term survival of Azospirillum followed by glycerol (10 mM) gum arabica (0.3%) and PVP (2%) and they supported 108 cells/ml up to 11 months of storage under ambient temperature (28°C to 32°C), whereas PEG (1%), PVA (0.5%) and control (lignite carrier) recorded the same population upto 8 months, 6 months and 5 months respectively. The results of the present study clearly indicated that the liquid formulation of Azospirillum could be used more effectively than the carrier based formulation

Vehicle Speed Measurement and Number Plate Detection using Real Time Embedded System

A real time system is proposed to detect moving vehicles that violate the speed limit. A dedicated digital signal processing chip is used to exploit computationally inexpensive image-processing techniques over the video sequence captured from the fixed position video camera for estimating the speed of the moving vehicles. The moving vehicles are detected by analysing the binary image sequences that are constructed from the captured frames by employing the inter-frame difference or the background subtraction techniques. The detected moving vehicles are tracked to estimate their speeds.This project deals with the tracking and following of single object in a sequence of frames and the velocity of the object is determined. The proposed method varies from previous existing methods in tracking moving objects, velocity determination and number plate detection. From the binary image generated, the moving vehicle is tracked using image segmentation of the video frames. The segmentation process is done by using the thresholding and morphological operations on the video frames. The object is visualized and its centroid is calculated. The distance it moved between frame to frame is stored and using this velocity is calculated with the frame rate of video.The images of the speeding vehicles are further analysed to detect license plate image regions. The entire simulation is done in matlab and simulink simulation software. Keywords:morphological;thresholding;segmentation;centroi

Tumors in von Hippel–Lindau Syndrome: From Head to Toe—Comprehensive State-of-the-Art Review

Von Hippel–Lindau syndrome (VHL) is an autosomal-dominant hereditary tumor disease that arises owing to germline mutations in the VHL gene, located on the short arm of chromosome 3. Patients with VHL may develop multiple benign and malignant tumors involving various organ systems, including retinal hemangioblastomas (HBs), central nervous system (CNS) HBs, endolymphatic sac tumors, pancreatic neuroendocrine tumors, pancreatic cystadenomas, pancreatic cysts, clear cell renal cell carcinomas, renal cysts, pheochromocytomas, paragangliomas, and epididymal and broad ligament cystadenomas. The VHL/hypoxia-inducible factor pathway is believed to play a key role in the pathogenesis of VHL-related tumors. The diagnosis of VHL can be made clinically when the characteristic clinical history and findings have manifested, such as the presence of two or more CNS HBs. Genetic testing for heterozygous germline VHL mutation may also be used to confirm the diagnosis of VHL. Imaging plays an important role in the diagnosis and surveillance of patients with VHL. Familiarity with the clinical and imaging manifestations of the various VHL-related tumors is important for early detection and guiding appropriate management. The purpose of this article is to discuss the molecular cytogenetics and clinical manifestations of VHL, review the characteristic multimodality imaging features of the various VHL-related tumors affecting multiple organ systems, and discuss the latest advances in management of VHL, including current recommendations for surveillance and screening

Significance of HOMO and LUMO studies on dye doped glycene lithium sulphate (GLS) crystals for non-linear optical applications

The ideal material that could have potential applications in non-linear optical (NLO) devices should possess the combination of large non-linear figure of merit for frequency conversion, high laser damage threshold, fast optical response time, wide phase matchable angle, architectural flexibility for molecular design and morphology, optical transparency and high mechanical strength. The stability of glycene lithium sulphate (GLS) single crystal has been improved by doping organic dyes. The structural, chemical, optical, mechanical and non-linear optical properties of the dye doped crystals have been analyzed with the characterization studies such as powder XRD, FT-IR, UV-Visible and SHG measurements, respectively. NMR, HOMO and LUMO energies have been performed by time dependent density functional theory (TD-DFT) approach. The Mulliken charge analysis indicates that the sulphur atoms of the benzene ring and the OH group attached to the ring are the main reactive centers of glycene lithium sulphate. And the temperature dependence of the thermodynamic properties of constant pressure (Cp), entropy (S) and enthalpy change (ΔH0→T) for glycene lithium sulphate have also been determined

Cloning of partial putative gonadotropin hormone receptor sequence from fish

A search for the presence of mariner-like elements in the Labeo rohita genome by polymerase chain reaction led to the amplification of a partial DNA sequence coding for a putative transmembrane domain of gonadotropin hormone receptor. The amplified DNA sequence shows a high degree of homology to the available turkey and human luteinizing and follicle stimulating hormone receptor coding sequences. This is the first report on cloning such sequences of piscine origin

Prognostic scoring system and risk stratification in patients with emphysematous pyelonephritis: an 11‐year prospective study at a tertiary referral centre

Objectives: To define pre‐morbid, clinical, laboratory, and imaging features and identify prognostic factors associated with morbidity and mortality in patients with emphysematous pyelonephritis (EPN) and develop a prognostic scoring system for improving management outcomes. / Patients and Methods: From January 2009 to December 2019, we performed a prospective study of all patients with a suspected diagnosis of EPN referred to a specialist tertiary centre in South India. All patients who underwent non‐contrast computed tomography of the abdomen and those diagnosed with EPN were included in this study. Demographic parameters, imaging, haematological and microbiology results were recorded. Patients were divided into three groups: Group 1, patients who survived without any intervention; Group 2, those who survived with surgical intervention; and Group 3, those who died with or without intervention. A prognostic scoring system was developed from 18 different parameters and risk stratification was developed. The scores were correlated with overall prognosis. / Results: Data from 131 patients with EPN enrolled in the study were analysed: Group 1 (n = 22), Group 2 (n = 102) and Group 3 (n = 7). By using univariate analysis, 10 factors were identified to be significantly associated with prognosis. Diabetes mellitus was the most common comorbidity. Shock at initial admission indicated a poor prognosis and warranted immediate attention (P < 0.001). / Conclusions: A multi‐disciplinary approach, a high index of clinical suspicion, an early diagnosis and administration of culture‐specific antibiotics with identification of prognostic indicators and risk stratification, allows prompt and appropriate medical and surgical treatments that could improve EPN management outcomes

Targeting Btk/Etk of prostate cancer cells by a novel dual inhibitor.

Btk and Etk/BMX are Tec-family non-receptor tyrosine kinases. Btk has previously been reported to be expressed primarily in B cells and has an important role in immune responses and B-cell malignancies. Etk has been shown previously to provide a strong survival and metastasis signal in human prostate cancer cells, and to confer androgen independence and drug resistance. While the role of Etk in prostate carcinogenesis is well established, the functions of Btk in prostate cancer have never been investigated, likely due to the perception that Btk is a hematopoietic, but not epithelial, kinase. Herein, we found that Btk is overexpressed in prostate cancer tissues and prostate cancer cells. The level of Btk in prostate cancer tissues correlates with cancer grades. Knockdown of Btk expression selectively inhibits the growth of prostate cancer cells, but not that of the normal prostate epithelial cells, which express very little Btk. Dual inhibition of Btk and Etk has an additive inhibitory effect on prostate cancer cell growth. To explore Btk and Etk as targets for prostate cancer, we developed a small molecule dual inhibitor of Btk and Etk, CTN06. Treatment of PC3 and other prostate cancer cells, but not immortalized prostate epithelial cells with CTN06 resulted in effective cell killing, accompanied by the attenuation of Btk/Etk signals. The killing effect of CTN06 is more potent than that of commonly used inhibitors against Src, Raf/VEGFR and EGFR. CTN06 induces apoptosis as well as autophagy in human prostate cancer cells, and is a chemo-sensitizer for docetaxel (DTX), a standard of care for metastatic prostate cancer patients. CTN06 also impeded the migration of human prostate cancer cells based on a 'wound healing' assay. The anti-cancer effect of CTN06 was further validated in vivo in a PC3 xenograft mouse model

MISFIRE DETECTION IN A MULTI-CYLINDER DIESEL ENGINE: A MACHINE LEARNING APPROACH

Misfire is another type of abnormal combustion. When engine misfires, cylinder (or cylinders) is not producing its normal amount of power. Engine misfire also has negative effects on engine exhaust emissions such as HC, CO, and NOx. Engine misfire should be detected and eliminated. Normal combustion and misfire in the cylinder (if any) generates vibrations in the engine block. The vibration characters due to misfire are unique for a particular cylinder. This can be diagnosed by processing the vibration signals acquired from the engine cylinder block using a piezoelectric accelerometer. The obtained signals were decoded using statistical parameters, like, Kurtosis, standard deviation, mean, median, etc. Misfire identification algorithms such as AdaBoost, LogitBoost, MultiClass Classifier, and J48 were used as tools for feature selection and classification. The signals were trained and tested by the selected classifiers. The classification accuracy of selected classifiers were compared and presented in this paper. MultiClass Classifier was found to be performing better with selected statistical features compared to other classifiers

EFFECT OF INCORPORATION OF WHEY PROTEIN CONCENTRATE ON QUALITY OF ICE CREAM

ABSTRACT Ice cream was prepared by replacing skimmed milk powder (SMP) wit