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Fast Uncertainty Quantification of Electromechanical Oscillation Frequency on Varying Generator Damping

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Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 2043-2048页

作者： Yongli Zhu Chanan singh Department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTX77840USA

This letter develops a fast analytical method for uncertainty quantification of electromechanical oscillation frequency due to varying generator dampings. By employing the techniques of matrix determinant reduction, two types of uncertainty analysis are investigated to quantify the impact of the generator damping on electromechanical oscillation frequency, i.e., interval analysis and probabilistic analysis. The proposed analytical frequency estimation formula is verified against conventional methods on two transmission system models. Then, Monte Carlo experiments and interval analysis are respectively conducted to verify the established lower/upper bound formulae and probability distribution formulae. Results demonstrate the accuracy and speed of the proposed method.

关键词： Electromechanical oscillation interval analysis Monte Carlo simulation quadratic eigenvalue problem uncertainty quantification

Long-term fertilizer nitrogen management—Soil health conundrum

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Pedosphere 2024年第1期34卷 23-25页

作者： BIJAY-singh Department of Soil Science Punjab Agricultural UniversityLudhiana 141004India

The mental model that fertilizer nitrogen (N) acts as a replacement for N mineralized from soil organic matter (SOM) needs to be revisited. Soil organic matter, the storehouse of N in soil, is one of the most important indicators of soil health. It supplies more N to crop plants than the current-year fertilizer N even when applied at high rates. Limited research shows that the application of fertilizer N above the optimum levels on a long-term basis deteriorates soil health by mineralizing SOM and depleting the soil N pool. Because soil N includes portions of fertilizer N applied in several previous years, year after year application of fertilizer N below the optimum levels will also lead to a gradual decline in soil N pool or soil health. To sustain high crop yield levels, fertilizer N needs to be applied on a long-term basis neither above nor below the optimum levels to ensure that soil health in terms of sustaining supply of soil N is maintained, if not enhanced.

关键词： soil Soil optimum

Properties of Ternary One Dimensional Plasma Photomic Crystals for an Obliquely Incident Electromagnetic Wave Considering the Effect of Collisions in Plasma Layers

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Plasma Science and Technology 2012年第12期14卷 1084-1090页

作者： S. PRASAD Vivek singh A. K. singh Department of Physics Faculty of ScienceBanaras Hindu University

An analytical study is presented on the modal dispersion characteristics, group velocity, and effective group, as well as the phase index of a ternary one dimensional plasma photonic crystal for an obliquely incident electromagnetic wave considering the effect of collisions in plasma layers. The dispersion relation is derived by using the transfer matrix method and the boundary conditions based on electromagnetic theory. The dispersion curves are plotted for both the normal photonic band gap structure and the absorption photonic band gap structure. It is found that the increase in the angle of incidence shifts the photonic band gap toward higher frequencies. Also, the cutoff frequency is independent of collisions.

关键词： ternary plasma photonic crystal dispersion curves group and phase velocities,obliquely incident collision effect

Geochronological and genetic characterization of basaltic basement from western offshore basins in India

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Geoscience Frontiers 2024年第5期15卷 372-398页

作者： Piyush Gupta Shakti singh Rathore Sandeep singh Geochronology Laboratory KDMIPEOil and Natural Gas Corporation Ltd.9Kaulagarh RoadDehradun 248195India Department of Earth Sciences Indian Institute of TechnologyRoorkee 247667India

^(40)Ar-^(39)Ar geochronology,geochemistry,and Sr-Nd isotopic compositions of 30 core samples from 24 offshore drill wells in the Western offshore basins have been used to characterize the genetics of the volcanic basement from the Kutch,Mumbai,and Kerala-Konkan offshore *** from the volcanic basement rocks demonstrate extremely varied isotopic and geochemical fingerprints,which are suggestive of significantly diverse parent magma compositions and emplacement *** tholeiitic basement from Kutch Offshore basin has Ar-Ar ages that range between 60 Ma and 62 *** basement is characterised by a within-plate basalt signature,with depleted isotopic signatures similar to least contaminated Deccan Traps basalts,and a component of subducted crustal *** basement from Mumbai Offshore Basin has eruption ages between 63 Ma and 65 Ma and show a strong within-plate OIB *** and isotopic signatures are consistent with Renuion lavas and an enriched-end member of Deccan Traps ***,Kerala-Konkan Offshore Basin shows significant E-MORB affinity and is characterized by primitive-mantle signatures and least contamination from the upper continental crust,with ages of eruption between 60 Ma and 61 Ma based on obtained^(40)Ar-^(39)Ar *** study suggests that the Mumbai Offshore Basalts’mode of the eruption was comparable with onshore Deccan volcanism,whereas the basaltic basement in Kutch Offshore was formed after the main phase of Deccan eruption and may have been an offshoot of a"tail"of the main Deccan *** parent magma for the volcanic E-MORB basement in the Kerala-Konkan Offshore Basin is thought to have come from mixing along the Carlsberg Mid-Oceanic Ridge and the material from the Réunion plume with the northward movement of the Indian Plate during the Early *** is thought to have occurred concurrently with the formation of the Chagos-Laccadive Ridge.

关键词： ^(40)Ar-^(39)Ar geochronology Western offshore basins Kutch offshore basin Mumbai offshore basin Kerala-Konkan offshore basin

Investigation of structural, morphological and electrochemical properties of mesoporous La2CuCoO6 rods fabricated by facile hydrothermal route

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 987-995页

作者： Jashandeep singh Ashok Kumar Department of Physics National Institute of Technology KurukhsetraHaryana 136119India Department of Applied Sciences National Institute of Technical Teachers Training and ResearchChandigarh 160019India

This work introduces the facile hydrothermal synthesis of double perovskite La2CuCoO6.X-ray diffraction pattern confirmed the formation of a monoclinic phase with P121/c1 *** electron microscopy results revealed that the self-assembled porous rods were composed of nanocrystallite *** estimated specific surface area of these mesoporous rods with an average pore diameter of 6 nm was^41 m^2·g^–*** presence of ions with oxidation states of La^3+,Cu^2+,and Co^2+/Co^3+on the surface of the mesoporous La2CuCoO6 rods was confirmed by X-ray photoelectron spectroscopic *** cyclicvoltammetry and chronopotentiometry,the electrode fabricated from the mesoporous La2CuCoO6 rods were found to exhibit pseudocapacitive behavior with a specific capacitance of 259.4 F·g^–1 at a current density of 0.5 A·g^–***^89%retention in specific capacitance was achieved after 1000 charge/discharge cycles at a constant current density of4 A·g^–1.

关键词： rare earth double perovskites oxide materials hydrothermal electrochemical

Indian summer monsoon rainfall (ISMR) forecasting using time series data: A fuzzy-entropy-neuro based expert system

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Geoscience Frontiers 2018年第4期9卷 1243-1257页

作者： Pritpal singh Smt. Chandaben Mohanbhai Patel Institute of Computer Applications CHARUSAT Campus

This study presents a model to forecast the Indian summer monsoon rainfall（ISMR）（June-September）based on monthly and seasonal time scales. The ISMR time series data sets are classified into two parts for modeling purposes, viz.,（1） training data set（1871-1960）, and（2） testing data set（1961-2014）.Statistical analyzes reflect the dynamic nature of the ISMR, which couldn＇t be predicted efficiently by statistical and mathematical based models. Therefore, this study suggests the usage of three techniques,viz., fuzzy set, entropy and artificial neural network（ANN）. Based on these techniques, a novel ISMR time series forecasting model is designed to deal with the dynamic nature of the ISMR. This model is verified and validated with training and testing data sets. Various statistical analyzes and comparison studies demonstrate the effectiveness of the proposed model.

关键词： Indian summer monsoon rainfall(ISMR) Fuzzy set Entropy Artificial neural network(ANN) Forecasting

Protracted zircon growth in migmatites and In situ melt of Higher Himalayan Crystallines:U-Pb ages from Bhagirathi valley, NW Himalaya,India

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Geoscience Frontiers 2019年第3期10卷 793-809页

作者： Sandeep singh Department of Earth Sciences Indian Institute of Technology Roorkee

The Higher Himalayan Crystallines(HHC), in western Garhwal, Uttarakhand are located in a regionalscale intracontinental ductile shear zone(15-20 km wide) bounded by the Main Central Thrust at the base, and the South Tibetan Detachment System at the top. The migmatite zone in the centre has the highest grade of metamorphism in the NW Himalayas and show evidence of flowage. Zircons extracted from samples of metasediment, migmatite, biotite granite and in situ partial melt(tourmaline-bearing leucogranite) along the Bhagirathi Valley, preserve U-Pb isotopic evidence of magmatic history, magma source and effects of the Himalayan orogeny in the region. Three distinct periods of zircon growth in the leucogranite record the episodic influx of magma between 46 Ma and 20 Ma indicating a time span of more than 25 Ma between the onset of fluid-fluxed partial melting in the mid-crustal intracontinental shear zone and the emplacement of the magma into the upper crust in a post-collisional extensional setting. Metamorphic zircon growth was initiated about 46 Ma, when the partial melts were generated as the migmatite zone was exhumed.

关键词： Himalayas Crustal anatexis Zircon SHRIMP U-Pb dating Migmatites Granites

Impact of surface Albedo on Martian photochemistry

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Earth and Planetary Physics 2020年第3期4卷 206-211页

作者： Deepak singh Physical Research Laboratory AhmedabadIndia

Solar energy is the primary driving force behind a planet’s climate system,and surface albedo plays a key role in determining the energy budget of the *** the Snow,Ice,and Aerosol Radiation(SNICAR)with the Laboratoire de Météorologie Dynamique(LMD)Mars General Circulation Model(MGCM)to create a new coupled model leads to an approximately 4%drop in the net CO2 ice deposition on *** simulated surface albedo affects the concentration of gaseous species in the Martian atmosphere(condensation-sublimation cycle).The new set-up also impacts the solar energy available in the *** two effects together lead to subsequent and significant changes in other chemical species in the Martian *** with results of the MGCM model alone,in the new coupled model CO2(gas)and O3 show a drop of about 1.17%and 8.59%in their respective concentrations,while H2O(vapor)and CO show an increase of about 13.63%and 0.56%in their respective *** trace species,OH shows a maximum increase of about 29.44%,while the maximum drop of 11.5%is observed in the O *** neutral species such as Ar and N2 remain unaffected by the albedo changes.

关键词： Mars Albedo snow photochemistry climate modelling

Multi-Objective Optimization of Fused Deposition Modeling for Mechanical Properties of Biopolymer Parts Using the Grey-Taguchi Method

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 51-64页

作者： Kapil Kumar Hari singh Department of Mechanical Engineering National Institute of TechnologyKurukshetra136119India

The urgent need to develop customized functional products only possible by 3D printing had realized when faced with the unavailability of medical devices like surgical instruments during the coronavirus-19 disease and the ondemand necessity to perform surgery during space *** have recently been the most appropriate option for fabricating surgical instruments via 3D printing in terms of cheaper and faster *** all 3D printing techniques,fused deposition modelling(FDM)is a low-cost and more rapid printing *** article proposes the fabrication of surgical instruments,namely,forceps and hemostat using the fused deposition modeling(FDM)*** mechanical properties are the only indicator to judge the quality of the functional *** mechanical properties of FDM-processed parts depend on various process *** parameters are layer height,infill pattern,top/bottom pattern,number of top/bottom layers,infill density,flow,number of shells,printing temperature,build plate temperature,printing speed,and fan *** strength and modulus of elasticity are chosen as evaluation indexes to ascertain the mechanical properties of polylactic acid(PLA)parts printed by *** experiments have performed through Taguchi’s L27orthogonal array(OA).Variance analysis(ANOVA)ascertains the significance of the process parameters and their percent contributions to the evaluation ***,as a multiobjective optimization technique,grey relational analysis(GRA)obtains an optimal set of FDM process parameters to fabricate the best parts with comprehensive mechanical *** electron microscopy(SEM)examines the types of defects and strong bonding between *** proposed research ensures the successful fabrication of functional surgical tools with substantial ultimate tensile strength(42.6 MPa)and modulus of elasticity(3274 MPa).

关键词： Fused deposition modeling Mechanical properties Taguchi method ANOVA Grey relational analysis SEM