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Neural Network and Fuzzy Control Based 11-Level Cascaded Inverter Operation

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Computers, Materials & Continua 2022年第2期70卷 2319-2346页

作者： Buddhadeva Sahoo sangram keshari routray Pravat Kumar Rout Mohammed M.Alhaider Department of Electrical Engineering Siksha‘O’Anusandhan UniversityOdisha751030India Department of Electrical Electronics Engineering Siksha‘O’Anusandhan UniversityOdisha751030India College of Engineering atWadi Addawaser Prince Sattam bin Abdulaziz University11991Saudi Arabia

This paper presents a combined control and modulation technique to enhance the power quality(PQ)and power reliability(PR)of a hybrid energy system(HES)through a single-phase 11-level cascaded H-bridge inverter(11-CHBI).The controller and inverter specifically regulate the HES and meet the load *** track optimum power,a Modified Perturb and Observe(MP&O)technique is used for ***-capacitor(UCAP)based energy storage device and a novel current control strategy are proposed to provide additional active power support during both voltage sag and swell *** an improved PQ and PR,a two-way current control strategy such as the main controller(MC)and auxiliary controller(AC)is suggested for the 11-CHBI *** is used to regulate the active current component through the fuzzy controller(FC),and AC is used to regulate the dc-link voltage of CHBI through a neural network-based PI controller(ANN-PI).By tracking the reference signals fromMC and AC,a novel hybrid pulse widthmodulation(HPWM)technique is proposed for the 11-CHBI *** justify and analyze the MATLAB/Simulink software-based designed model,the robust controller performance is tested through numerous steady-state and dynamic state case studies.

关键词： Ultra-capacitor 11-level cascaded H-bridge inverter hybrid energy system modified perturb and observer neural network-based PI fuzzy controller

Magnetic and ferroelectric properties of Zn and Mn co-doped BaTiO_3

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Chinese Physics B 2015年第6期24卷 564-570页

作者： sangram keshari Das Binod Kumar Roul Institute of Materials Science

This paper reports an approach to obtaining multiferroic properties in co-doped （Zn：Mn） BaTiO3 near room temper- ature. Interestingly, an unusual magnetic hysteresis loop is observed in the co-doped compositions in which the central portion of the loop is squeezed. However, in the composition ***3, a broad magnetic hysteresis loop is observed. Such a magnetic effect is attributed to the coexistence of antiferromagnetic and ferromagnetic exchange in- teractions in the system. The observation of the above type of magnetic properties is likely to be due to the presence of exchange interactions between Mn ions. A lossy-type of ferroelectric hysteresis loop is also observed in co-doped ceramic compositions near room temperature.

关键词： ferroelectrics ceramic ferromagnetic

Multidimensional Model for Vulnerability Assessment of Urban Flooding: An Empirical Study in Pakistan

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International Journal of Disaster Risk Science 2018年第3期9卷 359-375页

作者： Irfan Ahmad Rana Jayant K.routray Department of Urban and Regional Planning (URP) School of Civil and Environmental Engineering (SCEE) National University of Sciences and Technology (NUST) Regional and Rural Development Planning (RRDP) and Disaster Preparedness Mitigation and Management (DPMM) Department of Development and SustainabilityAsian Institute of Technology

Urban flooding has become a regular phenomenon in many towns and cities in the Asia Pacific region over the past years. Professionals associated with disaster management and climate change are at the forefront of addressing urban flooding. To reduce flood risks,vulnerability and its components must be *** assessment methods are diverse and complex, with a varied nature of understanding the key terms used in various contexts, and this diversity ultimately reflects on the interpretation of results in research *** interpretations and definitions exist in the disaster risk and climate change literature, complicating the process of astute and comprehensive vulnerability assessment. The main purpose of this study was to quantify vulnerability indicators and develop a multidimensional model for vulnerability assessment. Vulnerability is explored through the lens of five dimensions: social, economic, physical/infrastructural, institutional, and attitudinal. This methodology is applied to urban flooding in Pakistan, to verify the proposed model. Three study sites in urban areas with different population sizes, situated in high-risk flood zones in the Punjab Province of Pakistan were selected for empirical investigation. A household survey was conducted, and indices were developed for each dimension based on welldefined indicators. The proposed methodology for vulnerability assessment was tested and found operational. This method can be replicated irrespective of spatial scales and can be modified for other disasters by streamlining hazard specific indicators.

关键词： Pakistan Punjab Urban flooding Vulnerability assessment

Assessment of Variation in Morpho-Physiological Traits and Genetic Diversity in Relation to Submergence Tolerance of Five Indigenous Lowland Rice Landraces

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Rice science 2020年第1期27卷 32-43页

作者： Jijnasa BARIK Vajinder KUMAR sangram KLENKA Debabrata PANDA Department of Biodiversity and Conservation of Natural Resources Central University of OrissaKoraput 764021India ICAR-National Research Centre on Plant Biotechnology New Delhi 110012India TERI-Deakin NanoBiotechnology Centre the Energy and Resources InstituteGurugramHaryana 122001India

The present study evaluated submergence responses in 88 lowland indigenous rice(Oryza sativa L.) landraces from Koraput, India, to identify submergence-tolerant rice genotypes. In pot experiments, variations in survival rate, shoot elongation, relative growth index, dry matter, chlorophyll, soluble sugar and starch contents were evaluated in two consecutive years under well-drained and completely submerged conditions. Principal component analysis showed that the first three axes contributed 96.820% of the total variation among the landraces, indicating wide variation between genotypes. Major traits such as survival rate, relative growth index, soluble sugar and starch contents appeared to be important determinants of phenotypic diversity among the landraces. Phenotypic coefficient of variance was higher than genotypic coefficient of variance for all the traits and all showed high heritability(90.38%–99.54%). Five rice landraces(Samudrabali, Basnamundi, Gadaba, Surudaka and Dokarakuji) were the most tolerant to submergence. When submerged for up to 14d, Samudrabali, Basnamundi and Godoba were notable for having greater survival rates than a standard submergence tolerant variety FR13 A, and also notable for elongating more vigorously and accumulating more biomass. These three landraces may therefore be especially useful in lowland rice growing areas that are affected by both moderate stagnant water and flash flooding. Molecular genotyping revealed that the submergence tolerance of Samudrabali, Basnamundi and Godoba is linked to the presence of one or more different Sub1 loci and it may well prove useful for breeding improved submergence tolerant rice varieties, thereby assising to improve yield stability in the rainfed lowland agro-ecosystem.

关键词： genetic variability genotyping indigenous rice submergence tolerance Sub1 gene

Al2O3-TiO2/ZrO2-SiO2 based porous ceramics from particle-stabilized wet foam

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Journal of Advanced Ceramics 2017年第2期6卷 129-138页

作者： Bijay BASNET Naboneeta SARKAR Jung Gyu PARK sangram MAZUMDER Ik Jin KIM Institute of Processing and Application of Inorganic Materials(PAIM) Hanseo University # 360 Seosan-siChungnam 356-706 Republic of Korea School of Mechanical and Materials Engineering Washington State University Pullman Washington United States

The porous ceramics based on Al2O3-TiO2/ZrO2-SiO2 from particle-stabilized wet foam by direct foaming were *** initial Al2O3-TiO2 suspension was prepared by adding TiO2 suspension to partially hydrophobized colloidal Al2O3 suspension with equimolar amount,to form Al2TiO5 on *** secondary ZrO2-SiO2 suspension was prepared using the equimolar composition,and to obtain ZrSiO4,ZrTiO4,and mullite phases in the sintered samples,the secondary suspension was blended into the initial suspension at 0,10,20,30,and 50 vol％.The wet foam exhibited an air content up to 87％,Laplace pressure from 1.38 to 2.23 mPa,and higher adsorption free energy at the interface of approximately 5.8×108 to 7.5×108J resulting an outstanding foam stability of 87％.The final suspension was foamed,and the wet foam was sintered from 1400 to 1600 ℃ for 1 *** porous ceramics with pore size from 150 to 400 μm on average were *** phase identification was accomplished using X-ray diffraction (XRD),differential thermal analysis (DTA),and thermogravimetric analysis (TGA),and microstructural analysis was performed using field emission scanning electron microscopy (FESEM).

关键词： Al2TiO5 direct foaming Laplace pressure adsorption free energy porous ceramics

Effect of metal-fingers/doped-ZnO transparent electrode on performance of GaN/InGaN solar cell

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Journal of Semiconductors 2017年第9期38卷 1-7页

作者： S.R.routray T.R.Lenka Microelectronics and VLSI Design Group Department of Electronics and Communication EngineeringNational Institute of Technology SilcharAssam788010India

The effect of doped-ZnO transparent conductive oxide （TCO） with metal （Ag）-fingers contact on GaN/InGaN solar cell is investigated through numerical simulations. An optical and electrical analysis of different dopant elements （such as B, A1, Ga, In and Sn） with ZnO as a top TCO layer is studied. A comparative analysis of metal square pad electrode, metal grid pattern electrode and metal-finger/ZnO type electrodes are taken into consideration to ensure the effect of anti-reflectivity by ZnO. The effect of thickness of ZnO and i-InGaN layer on performance of solar cell is also studied in detail. The proposed solar cell structure with Ag-fingers/ZnO：Al as top contact electrode shows interesting device characteristics compared to other dopants and metal top electrodes. The device achieves open circuit voltage -2.525 V, short circuit current -4.256 mA/cm^2, fill factor -87.86% and efficiency -9.22% under 1 Sun, air mass 1.5 global illumination.

关键词： Ag-finger/doped-ZnO TCO resistivity dopants GaN/InGaN solar cell

Influence of Operating Parameters on Unbalance in Rotating Machinery Using Response Surface Method

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Sound & Vibration 2018年第5期52卷 12-21页

作者： Ameya MMahadeshwar sangram SPatil Vishwadeep CHandikherkar Vikas M.Phalle Veermata Jijabai Technological Institute H R Mahajani MargMatungaMumbai400019Maharashtra

Wide range of rotating machinery contains an inherent amount of unbalance which leads to increase in the vibration level and related *** this work,the effect of different operating conditions *** unbalanced weight,radius,speed and position of the rotor disc on the unbalance in rotating machine are studied experimentally and analyzed by using Response Surface Methodology(RSM).RSM is a technique which consists of mathematical and statistical methods to develop the relationship between the inputs and outputs of a system by distinct functions.L27 Orthogonal Array(OA)was developed by using Design of Experiments(DOE)according to which experimentation has been carried *** accelerometer sensors were mounted to record the vibration responses(accelerations)in radially vertical,horizontal and axial *** responses recorded as root mean square values are then analysed using *** relationship between response and operating factors has been established by developing a second order,non-linear mathematical *** of variance(ANOVA)has been performed for verification of the developed mathematical *** obtained from the analysis show that the unbalance weight and speed are most significant operating conditions that contribute the most to the effect the unbalance has on the rotating spindle.

关键词： Mechanical unbalance response surface method rotating machinery ANOVA design of experiments

Additive friction stir deposition of AZ31B magnesium alloy

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Journal of Magnesium and Alloys 2022年第9期10卷 2404-2420页

作者： Sameehan S.Joshi Shreyash M.Patil sangram Mazumder Shashank Sharma Daniel A.Riley Shelden Dowden Rajarshi Banerjee Narendra B.Dahotre Department of Materials Science and Engineering University of North Texas3940 N Elm StDentonTX 76207USA Center for Agile and Adaptive Additive Manufacturing University of North Texas3940 N Elm StDentonTX 76207USA

The current work explored additive friction stir deposition of AZ31B magnesium alloy with the aid of MELD?***31B magnesium bar stock was fed through a hollow friction stir tool rotating at constant velocity of 400 rpm and translating at linear velocity varied from 4.2 to 6.3 mm/s.A single wall consisting of five layers with each layer of 140×40×1 mm^(3)dimensions was deposited under each processing ***,phase,and crystallographic texture evolutions as a function of additive friction stir deposition parameters were studied with the aid of scanning electron microscopy including electron back scatter diffraction and X-ray *** feed material and additively produced samples consisted of theα-Mg *** additively produced samples exhibited a refined grain structure compared to the feed *** feed material appeared to have a weak basal texture,while the additively produced samples experienced a strengthening of this basal *** additively produced samples showed a marginally higher hardness compared to the feed *** current work provided a pathway for solid state additive manufacturing of Mg suitable for structural applications such as automotive components and consumable biomedical implants.

关键词： Additive friction stir deposition Magnesium alloys Additive manufacturing Thermomechanical processing Materials processing Solid state additive manufacturing

Reducibility of Periodic Quasi-Periodic Systems

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International Journal of Modern Nonlinear Theory and Application 2014年第1期3卷 6-14页

作者： Evi Ezekiel sangram Redkar Department of Engineering Arizona State University at Polytechnic Campus Mesa USA

In this work, the reducibility of quasi-periodic systems with strong parametric excitation is studied. We first applied a special case of Lyapunov-Perron (L-P) transformation for time periodic system known as the Lyapunov-Floquet (L-F) transformation to generate a dynamically equivalent system. Then, we used the quasi-periodicnear-identity transformation to reduce this dynamically equivalent system to a constant coefficient system by solving homological equations via harmonic balance. In this process, we obtained the reducibility/resonance conditions that needed to be satisfied to convert a quasi-periodic system in to a constant one. Assuming the reducibility is possible, we obtain the L-P transformation that can transform original quasi-periodic system into a system with constant coefficients. Two examples are presented that show the application of this approach.

关键词： L-P Transformation Quasi-Periodic System Reducibility