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Design of a Robust Optimal Decentralized PI Controller Based on Nonlinear Constraint Optimization For Level Regulation: An Experimental Study

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 187-199页

作者： Soumya ranjan Mahapatro Bidyadhar Subudhi Sandip ghosh Department of Electrical Engineering National Institute of Technology RourkelaRourkela 769008India School of Electrical Sciences Indian Institute of TechnologyFarmagudiGoa 403401India Department of Electrical Engineering Indian Institute of TechnologyVaranasi 221005India

This paper presents the development of a new robust optimal decentralized PI controller based on nonlinear optimization for liquid level control in a coupled tank system. The proposed controller maximizes the closed-loop bandwidth for specified gain and phase margins, with constraints on the overshoot ratio to achieve both closed-loop performance and robustness. In the proposed work, a frequency response fitting model reduction technique is initially employed to obtain a first order plus dead time(FOPDT) model of each higher order subsystem. Furthermore, based on the reduced order model, a proposed controller is designed. The stability and performance of the proposed controller are verified by considering multiplicative input and output uncertainties. The performance of the proposed optimal robust decentralized control scheme has been compared with that of a decentralized PI controller. The proposed controller is implemented in real-time on a coupled tank system. From the obtained results,it is shown that the proposed optimal decentralized PI controller exhibits superior control performance to maintain the desired level, for both the nominal as well as the perturbed case as compared to a decentralized PI controller.

关键词： Decentralized control multivariable system process control parameter uncertainty robustness

Multi-phase computer modeling and laboratory study of dust capture by an inertial Vortecone scrubber

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International Journal of Mining Science and Technology 2020年第3期30卷 287-291页

作者： Ashish ranjan Kumar Steven Schafrik Thomas Novak Department of Mining Engineering University of Kentucky504 Rose Street230 Mining and Mineral Resources BuildingLexingtonKY 40506United States

Dust generated in mining and tunneling activities is hazardous to health of persons and safety of operations. These projects employ pick-milling machines to extract minerals and rock by mechanical *** machines are equipped with flooded-bed scrubbers that encase dust particles within fine water films as particles encounter a flooded wire-mesh screen. A major disadvantage is that the screen gets clogged when particles become trapped within the wire mesh, reducing airflow through the scrubber and increasing ambient dust concentrations. Thus, the system requires frequent maintenance or replacement. The application of a Vortecone scrubber as an improved alternative to conventional fibrous type scrubbers is investigated. A Vortecone forces dust-laden air and water to follow a complex, rapidly swirling *** momentum drives dust particles towards the periphery where they are captured by the water *** operating characteristics of a reduced-scale physical model of a Vortecone, with its primary axis mounted in the horizontal orientation, was analyzed numerically and experimentally. Computational fluid dynamics(CFD) models depicting the spraying action and multi-phase air/water flows using the volume of fraction(VOF) approach, are presented. Experimental results, utilizing an optical particle counting technique to establish the dust-cleaning capabilities of the model, are also described.

关键词： Computational fluid dynamics(CFD) Process safety Multi-phase flows Volume of fraction(VOF) Dust-capture Cleaning efficiency

Appropriate method of core selection and crosstalk optimization in single-mode homogeneous multicore fiber

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Optoelectronics Letters 2020年第2期16卷 126-130页

作者： DABLU Kumar RAKESH ranjan Optical Fiber Communication and Photonics Lab Department of Electronics and Communication EngineeringNational Institute of Technology(NIT)PatnaPatna 800005India

The approach for homogeneous core structure design and selection based on low crosstalk, low dispersion, and acceptable mode effective area have been explored. The forward and backward crosstalk behaviors with respect to wavelength, fiber bending radius, and twisting rate in 12-core, and 21-core single-mode trench-assisted homogenous multicore fiber have been analyzed. The new expression for forward crosstalk under bending and twisting conditions has been derived using the conventional method. For the analysis and optimization of crosstalk, three different core structures are considered, it helps to draw the attention to select the appropriate core structure model for multicore fiber, which follows the standards used in telecom services.

关键词： crosstalk fiber trench

An efficient and comparative adsorption of Congo red and Trypan blue dyes on MgO nanoparticles: Kinetics, thermodynamics and isotherm studies

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Journal of Magnesium and Alloys 2021年第2期9卷 478-488页

作者： Barsharani Priyadarshini Tanaswini Patra Tapas ranjan Sahoo Department of Chemistry School of Applied SciencesKIIT deemed to be UniversityBhubaneswar 24OdishaIndia

Cubic phase of Mg O nanoparticles were prepared by microwave-assisted combustion synthesis and investigated for the removal of toxic dyes like Congo Red(CR)and Trypan blue(TB).The crystallite size of the Mg O nanoparticle was calculated to be 18 nm from XRD *** sample was further characterized by FTIR,TgA and FESEM *** dyes were subjected to prototypical batch adsorption process,including investigation of different parameters like Mg O dosage,dye concentration,solution pH,agitation speed and *** was found that,0.2 g of Mg O NPs showed maximum removal efficiency for both the dyes(more than 98%),having 25 ppm of dye concentration at an acidic p H(3–4).The maximum loading capacity of Mg O NPs was obtained to be 136 mg/g and 132 mg/g for CR and TB,*** thermodynamic parameters like△g^(0),△H^(0)and△S^(0)were *** negative△H^(0)and the positive△S^(0)values for both the dyes correspond to an exothermic process and an increase in randomness of the adsorbent and *** isotherm analysis exhibited that the Freundlich model fits better to the experimental equilibrium data,suggesting heterogeneous surface of the ***,the kinetic data revealed a pseudo 2 nd order rate for adsorption process.

关键词： Adsorption Congo red Trypan blue MgO NPs Kinetics Isotherm

Evaluation of vertical impact factor coefficients for continuous and integral railway bridges under high-speed moving loads

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Earthquake Engineering and Engineering Vibration 2021年第2期20卷 495-504页

作者： Anand M.gharad ranjan S.Sonparote Civil Engineering Department Shri Ramdeobaba College of Engineering and ManagementNagpur 440013India Department of Applied Mechanics Visvesvaraya National Institute of TechnologyNagpur 440010India

In the railway bridge analysis and design method,dynamic train loads are regarded as static loads enhanced by an impact factor(IF).The IF coefficients for various railway bridges have been reported as a function of span length or frequency of the bridges in Eurocode(2003).However,these IF coefficient values neglect the effects of very high speeds(>200 km/h)and soil-structure interaction(SSI).In this work,a comprehensive study to assess the impact factor coefficients of mid-span vertical displacements for continuous and integral railway bridges subjected to high-speed moving loads is *** different configurations,each for the three-dimensional(3D)continuous and integral bridge,are ***,single-track(1-T)and two-track(2-T)“real train”loading cases for both these bridge types are ***,finite element analysis of the full-scale 3D bridge models,to identify their IF values,considering the effects of SSI for three different soil conditions,is *** IF values obtained from the study for both bridge types are comparable and are greater than the values recommended by Eurocode(2003).The results reveal that with a loss of soil stiffness,the IF value reduces;thus,it confirms the importance of SSI analysis.

关键词： impact factor dynamic soil-structure interaction high-speed moving loads finite element analysis continuous bridge integral bridge

Nonlinear dynamic analysis of dragonfly-inspired piezoelectric unimorph actuated flapping and twisting wing

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International Journal of Smart and Nano Materials 2012年第2期3卷 103-122页

作者： Sujoy Mukherjee ranjan ganguli Department of Aerospace Engineering Indian Institute of ScienceBangalore-560012KarnatakaIndia

The nonlinear equations for coupled elastic flapping-twisting motion of a dragonfly-inspired smart flapping wing are used for a flapping wing actuated from the root by a PZT unimorph in the piezofan *** by the piezoelectric harmonic force generates only the flap bending motion,which,in turn,induces the elastic twist motion due to interaction between flexural and torsional vibration *** unsteady aerodynamic model is used to obtain the aerodynamic *** simulations are performed using a wing whose size is the same as the dragonfly Sympetrum frequens *** is found that the value of average lift reaches its maximum when the smart flapping wing is excited at a frequency closer to the natural frequency in ***,consideration of the elastic twisting of the flapping wing leads to an increase in the lift *** is also found that the flapping wing generates sufficient lift to support its own weight and carry a small ***,the piezoelectrically actuated smart flapping wing based on the geometry of a Sympetrum frequens wing and undergoing flapping-twisting motions can be considered as a potential candidate for use in micro air vehicle applications.

关键词： piezofan nonlinear vibration coupled flapping-twisting dragonfly smart material micro air vehicle

Enhancing Critical Path Problem in Neutrosophic Environment Using Python

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2957-2976页

作者： M.Navya Pratyusha ranjan Kumar VIT-AP University InavoluBesides AP SecretariatAmaravati APIndia

In the real world,one of the most common problems in project management is the unpredictability of resources and *** efficient way to resolve uncertainty problems and overcome such obstacles is through an extended fuzzy approach,often known as neutrosophic *** rigorous proposed model has led to the creation of an advanced technique for computing the triangular single-valued neutrosophic *** innovative approach evaluates the inherent uncertainty in project durations of the planning phase,which enhances the potential significance of the decision-making process in the *** proposed method,for the first time in the neutrosophic set literature,not only solves existing problems but also introduces a new set of problems not yet explored in previous research.A comparative study using Python programming was conducted to examine the effectiveness of responsive and adaptive planning,as well as their differences from other existing models such as the classical critical path problem and the fuzzy critical path *** study highlights the use of neutrosophic logic in handling complex projects by illustrating an innovative dynamic programming framework that is robust and flexible,according to the derived results,and sets the stage for future discussions on its scalability and application across different industries.

关键词： Classical critical path problem fuzzy critical path problem uncertainty neutrosophic triangular single-valued neutrosophic number neutrosophic critical path problem python programming languag

Modelling of Wideband Concentric Ring Frequency Selective Surface for 5g Devices

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Computers, Materials & Continua 2023年第1期74卷 341-361页

作者： Ankush Kapoor Pradeep Kumar ranjan Mishra Department of Electronics and Communication Engineering Jawaharlal Nehru Government Engineering CollegeSundernagar175018India Discipline of Electrical Electronic and Computer EngineeringUniversity of KwaZulu-NatalDurban4041South Africa Department of Electrical and Electronics Engineering University of Petroleum and Energy StudiesDehradun248007India

Frequency selective surfaces(FSSs)play an important role in wireless systems as these can be used as filters,in isolating the unwanted radiation,in microstrip patch antennas for improving the performance of these antennas and in other 5g *** analysis and design of the double concentric ring frequency selective surface(DCRFSS)is presented in this *** the sub-6 gHz 5g FR1 spectrum,a computational synthesis technique for creating DCRFSS based spatial filters is *** analytical tools presented in this study can be used to gain a better understanding of filtering processes and for constructing the spatial *** of the loop sizes,angles of incidence,and polarization of the concentric rings are the factors which influence the transmission coefficient as per the thorough investigation performed in this paper.A novel synthesis approach based on mathematical equations that may be used to determine the physical parameters ofDCRFSSbased spatial filters is *** proposed synthesis technique is validated by comparing results from high frequency structure simulator(HFSS),Ansys electronic desktop circuit editor,and an experimental ***,the findings acquired from a unit cell are expanded to a 2×2 array,which shows identical performance and therefore proves its stability.

关键词： Spatial filters double concentric ring frequency selective surface(DCRFSS) angle of incidence finite element method(FEM) polarization angles

Pattern of spatial variability in granulometric and mineralogical characteristics across an ecologically sensitive sub-tropical wetland(Bihar, India)

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International Journal of Sediment Research 2023年第4期38卷 516-529页

作者： Alvia Aslam Rajesh Kumar ranjan Avinash Dass Department of Environmental Science Central University of South Bihar

Floodplain wetlands are dynamic systems undergoing frequent hydro-sedimentological changes. Tropical/subtropical wetlands have even more pronounced climatic and biological influences on the sediment dynamics. In the current study, a protected subtropical wetland in Bihar(India) has been assessed for its sedimentary and mineralogical status. Sediment characteristics and associated granulometric parameters are discussed to highlight the wetland’s hydrogeomorphic character, energy dimension, and the depositional processes taking place. Statistical grain size parameters like graphic mean, graphic skewness,graphic kurtosis, and their interrelations studies have helped in understanding the sources of deposited materials. Multivariate statistics have identified, sand fractions, measures of central tendencies(mean,median, and mode), percent organic matter(%OM) and percent carbonates(%carbonates) as primary factors explaining the maximum variance in the data. The non-parametric Kruskal-Wallis test has identified %sand, %clay, electrical conductivity(EC), and %carbonates as the major factors responsible for significant spatial variability. The grain texture analysis shows that the majority of samples fall in the brackets of clayey silt; silty sand; and sand, silt, and clay. Common mineral components associated with these are quartz, feldspar, clay minerals, etc. The range for the mean grain size lies between 3Φ to 9Φ(Φ is diameter of the sediments) where most of the grain size distributions are symmetrically to fine symmetrically skewed, indicating intermediate energy to adjust to environmental conditions. The granulometric and physicochemical characteristics of the sediment samples also indicate the directional distribution pattern of sediment along the hydrological pathway. Future studies concentrating on the fluvial discharges of water and sediment will be highly insightful in reconstructing the past net sediment accumulation processes in the Baraila Wetland.

关键词： grain size analysis Hydrodynamic energy Mineralogy Allogenic source Terrigenous input Wetland