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Tracking sources and paleotectonic settings of Mesozoic sandstones in interlinked rift basins of western India:An integrated approach using petrography and heavy mineral chemistry

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Journal of Palaeogeography 2022年第2期11卷 173-193页

作者： pawan kumar Rajak Angana Chaudhuri Naraga Prabhakar Santanu Banerjee Department of Earth Sciences Indian Institute of Technology BombayMumbai 400076India

Based on integration of field,petrographic and heavy mineral chemical data,this study highlights the source and tectonic setting of the Mesozoic sandstones of Kutch,Saurashtra,Narmada and Cambay basins at the western margin of India,formed by the progressive splitting of the eastern *** Kutch Basin is dominated by arkosic sandstone,whereas Saurashtra,Narmada and Cambay basins show the predominance of sub-arkose and *** modal analyses of framework grains in Kutch sandstones indicate basement uplift and transitional continent *** contrast,the sandstones of Saurashtra,Narmada and Cambay basins bear imprints of recycled orogenic and craton interior *** presence of abraded and detrital quartz overgrowth and rounded zircons in most sandstones reveal the recycling of sediments in these *** and rutile mineral compositions constrain the possible lithology of source *** tourmaline mineral chemistry(Ca-Fe_(tot)-Mg plot)suggests the derivation of sediments from various sources,including Li-poor granitoids associated with pegmatites,aplites,Ca-poor metapelites,metapsammites and quartz-tourmaline-rich granitic *** compositions of rutile grains(Cr *** plot)in sandstones indicate metapelitic *** gamut of all mineral chemical data supports the predominance of sediment sources from quartzo-feldspathic rocks with minor inputs from mafic *** on available paleocurrent data and correlation of source compositions,we infer that the Mesozoic sediments of Kutch,Saurashtra,Narmada and Cambay basins were primarily sourced by various lithologies of the Aravalli *** Narmada Basin possibly received additional sediment input from the Bundelkhand Craton.

关键词： Mesozoic sandstones Rift basins Tourmaline chemistry Rutile chemistry Kutch Basin Saurashtra Basin Cambay Basin Narmada Basin

Optical anisotropy and the direction of polarization of exciton emissions in a semiconductor quantum dot:Effect of heavy-and light-hole mixing

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Chinese Physics B 2017年第8期26卷 400-406页

作者： Ranber singh Rajiv kumar Vikramjeet singh Department of Physics Sri Guru Gobind Singh CollegeSector 26Chandigarh 160019India Department of Physics DAV University JalandharPunjab 144012India IKGPTU Campus HoshiarpurPunjab 146001India

The dependence of the directions of polarization of exciton emissions, fine structure splittings （FSS）, and polarization anisotropy on the light- and heavy-hole （LH-HH） mixing in semiconductor quantum dots （QDs） is investigated using a mesoscopic model. In general, all QDs have a four-fold exciton ground state. Two exciton states have directions of polarization in the growth-plane, while the other two are along the growth direction of the QD. The LH-HH mixing does affect the FSS and polarization anisotropy of bright exciton states in the growth-plane in the low symmetry QDs （e.g., C2v, CS, C1 ）, while it has no effect on the FSS and polarization anisotropy in high symmetry QDs （e.g., C3V, D2d）. When the hole ground state is pure HH or LH, the bright exciton states in the growth-plane are normal to each other. The LH-HH mixing affects the relative intensities and directions of bright exciton states in the growth-plane of the QD. The polarization anisotropy of exciton emissions in the growth-plane of the QD is independent of the phase angle of LH-HH mixing but strongly depends on the magnitude of LH-HH mixing in low symmetry QDs.

关键词： light-heavy hole mixing excitons quantum dots

Multifunctional characteristics of 3D printed polymer nanocomposites under monotonic and cyclic compression

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Defence Technology（防务技术） 2023年第12期30卷 13-22页

作者： pawan Verma Jabir Ubaid Fahad Alam Suleyman Deveci S.kumar Department of Mechanical Engineering Khalifa University of Science and TechnologyMasdar InstituteMasdar CityP.O.Box 54224Abu DhabiUnited Arab Emirates Borouge Pte.Ltd. Innovation CentreSas Al Nakhl6951Abu DhabiUnited Arab Emirates James Watt School of Engineering University of GlasgowGlasgowG128QQUK

This study presents the multifunctional characteristics of multi-walled carbon nanotube(MWCNT)/polypropylene random copolymer(PPR) composites enabled via fused filament fabrication(FFF) under monotonic and quasi-static cyclic compression. Utilizing in-house MWCNT-engineered PPR filament feedstocks, both bulk and cellular composites were realized. The morphological features of nanocomposites were examined via scanning electron microscopy, which reveals that MWCNTs are uniformly dispersed. The uniformly dispersed MWCNTs forms an electrically conductive network within the PPR matrix, and the resulting nanocomposite shows good electrical conductivity(~10^(-1)S/cm), improved mechanical performance(modulus increases by 125% and compressive strength increases by 25% for 8 wt% MWCNT loading) and pronounced piezoresistive response(gauge factor of 27.9-8.5 for bulk samples)under compression. The influence of strain rate on the piezoresistive response of bulk samples(4 wt% of MWCNT) under compression was also measured. Under repeated cyclic compression(2% constant strain amplitude), the nanocomposite exhibited stable piezoresistive performance up to 100 cycles. The piezoresistive response under repeated cyclic loading with increasing strain amplitude of was also *** gauge factor of BCC and FCC cellular composites(4 wt% of MWCNT) with a relative density of 30%was observed to be 46.4 and 30.2 respectively, under compression. The higher sensitivity of the BCC plate-lattice could be attributed to its higher degree of stretching-dominated deformation behavior than the FCC plate-lattice, which exhibits bending-dominated behavior. The 3D printed cellular PPR/MWCNT composites structures were found to show excellent piezoresistive self-sensing characteristics and open new avenues for in situ structural health monitoring in various applications.

关键词： Carbon nanotubes Nanoengineered polymer composites 3D printing Piezoresistive self-sensing Lattice structures

Information hiding with adaptive steganography based on novel fuzzy edge identification

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Defence Technology（防务技术） 2019年第2期15卷 162-169页

作者： Sanjeev kumar Amarpal singh Manoj kumar I.K.G Punjab Technical University Department of ECE Beant College of Engineering & Technology DAV Institute of Engineering & Technology

The evolution in communication techniques has created wide threats for crucial information transfer through a communication channel. Covert communication with steganography is a skill of concealing secret information within cover object and hence shields the data theft over rapidly growing ***, diverse steganography techniques using edge identification have been proposed in *** methods however utilize certain pixels in the cover image for inserting edge information,resulting in significant deformation. The conventional edge detection method limits the deployment of edge detection in steganography as concealing the information would introduce some variations to the cover image. Hence inserting data in pixel areas recognized by existing conventional edge detection techniques like canny cannot ensure the recognition of the exact edge locations for the cover and stego images. In this paper, an Adaptive steganography method based on novel fuzzy edge identification is proposed. The method proposed is proficient of estimating the precise edge areas of a cover image and also ensures the exact edge location after embedding the secret message. Experimental results reveal that the technique has attained good imperceptibility compared to the Hayat AI-Dmour and Ahmed AIAni Edge XOR method in spatial domain.

关键词： Information security Adaptive steganography Fuzzy edge detection Pattern recognition

Application of Response Surface Methodology for Analysing and Optimizing the Finned Solar Air Heater

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Journal of Thermal Science 2024年第3期33卷 985-1009页

作者： Vineet singh Vinod singh YADAV Vaibhav TRIVEDI Manoj kumar Niraj kumar Department of Mechanical Engineering School of Engineering&TechnologyIFTM UniversityMoradabadUttar PradeshIndia Department of Mechanical Engineering NITUttarakhandPauriUttarakhandIndia Department of Electronics and Communication Engineering Jaypee Institute of Information TechnologyNoidaUttar Pradesh201309India

In this research paper,a solar air heater with triangular fins has been experimentally analysed and ***,an experimental set-up of a solar air heater having triangular fins has been developed at the location of 28.10°N,78.23°*** heat transfer rate through fins and fins efficiency has been determined by the Finite Difference Method model *** experimental data and modeled data of response parameters have been optimized in MINITAB-17 software by the Response Surface Methodology *** creating the response surface design,three input parameters have been selected namely solar intensity,Reynolds number,and fin base-to-height *** range of solar intensity,Reynolds number,and fin base-to-height ratio is 600 to 1000W/m^(2),4000 to 6000,and 0.4 to 0.8 *** response surface design has been analyzed by calculating the outlet temperature,friction factor,Nusselt number,fin efficiency,thermal performance factor,and exergy *** optimum settings of input parameters:solar intensity is 1000 W/m^(2);Reynolds number is 4969.7,and the fin base to height ratio is 0.6060,on which these response:namely outlet temperature of 92.531℃,friction factor of 0.2350,Nusselt number of 127.761,thermal efficiency of 50.836%,thermal performance factor of 1.4947,and exergy efficiency of 8.762%.

关键词： solar air heater optimization fins exergy response surface methodology air

Grid Tied Solar PV System with Power Quality Enhancement Using Adaptive Generalized Maximum Versoria Criterion

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 722-732页

作者： Manoj Badoni Alka singh Ankit kumar singh Hemant Saxena Rajeev kumar Delhi Technological University Delhi 110042India.A.K.Singh is with Netaji Subhas University of TechnologyDelhi 110078India Netaji Subhas University of Technology Delhi 110078India Electrical and Electronics Engineering Department KIET Group of InstitutionsGhaziabadIndia Electrical Engineering Department Jamia Millia IslamiaNew DelhiIndia

A three phase grid tied solar photovoltaic(PV)system with power quality compensation features is presented in this *** system is used to transfer power generated from a solar PV array to feed linear and nonlinear loads along with compensation for several power quality(PQ)issues,such as harmonics,redundant reactive power and load *** generated DC power from the PV array is converted into AC by implementing a three-phase voltage source converter(VSC).In order to transfer active power and mitigate PQ problems,an efficient control technique is required for the grid tied solar PV *** study presents the use of an adaptive generalized maximum Versoria criterion(AGMVC)controller for VSC used in a solar PV energy conversion *** utilization of the solar PV array is accomplished by using the Perturb and Observe based maximum power point tracking(MPPT)*** experimental setup of the grid integrated PV system is implemented in the laboratory using an IGBT based VSC and DSP(dSPACE DS-1202).The performance of the AGMVC control technique is verified experimentally using laboratory *** control technique is compared with different conventional controllers,such as synchronous reference frame theory(SRFT)and instantaneous reactive power theory(IRPT)along with recently developed weight-based controllers viz.,least mean square(LMS),least mean mixed norm(LMMN)and normalized kernel least mean fourth-neural network(NKLMFNN).Numerous terms,such as fundamental weight convergence,steady state error,computational complexity,phase lock loop(PLL)requirement and harmonic compensation capability,are considered for comparison purposes of AGMVC with the above listed control *** system performance is verified according to the IEEE-519 standard.

关键词： Harmonics maximum versoria criterion power factor corection(PFC) solar photovoltaic

Depillaring of total thickness of a thick coal seam in single lift using cable bolts：A case study

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International Journal of Mining Science and Technology 2016年第2期26卷 223-233页

作者： kumar Rakesh Mishra Arvind kumar singh Arun kumar singh Amit kumar Ram Sahendr singh Rajendr Central Institute of Mining and Fuel Research (under CSIR) Dhanbad 826015 India Indian School of Mines Dhanbad 826004 India

Explaining fundamentals of application of cable bolting for a thick seam depillaring,this paper summarizes the results of field studies conducted during adoption of this approach in more than fifteen panels of Madhusudanpur 7 pit and incline *** 7.0 m thick Kajora top coal seam of this mine is developed on pillars along the floor horizon to an average height of 3.0 m,leaving a coal band of around 4.0 m along the *** of procured core samples showed that roof strata are easily caveable with a caveability index value of around 2000 *** caveable overlying strata and shallow depth of cover alleviated most of the expected strata mechanics problems of the thick seam ***,extraction of total thickness at shallow cover caused differential-subsidence and cracks on the *** manifestations were immediately tackled to avoid creation of a breathing path for spontaneous heating in the extracted area.

关键词： Cable bolting Thick seam depillaring Extraction height Pillar stability Caveability index

Underground mining of thick coal seams

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International Journal of Mining Science and Technology 2015年第6期25卷 885-896页

作者： kumar Rakesh singh Arun kumar Mishra Arvind kumar singh Rajendra Central Institute of Mining and Fuel Research (CIMFR under CSIR) Indian School of Mines (ISM)

This paper reviews underground mining methods for total thickness of a thick coal seam in single lift （TI＇rCSSL）. Review shows the required engineering for extraction of thick seams needs to be fitted with thickness of the seam, behavior of rock-mass and surrounding stress conditions for efficient mining. Variants of TI＇rCSSL are able to extract a maximum 10-12 m thickness only. An improvement in bending moment of the overlying coal band in longwall top coal caving （LTCC） provides better under-winning opportunity for the roof coal band. An acceptable limit of 25 MPa compressive strength of coal for the success of LTCC may be increased under favorable geo-technical conditions. Bord and pillar in India adopted induced caving of roof coal band for single lift depillaring of total thickness （SLDTr） of a compe- tent thick coal seam developed along floor. Case studies are given to arrest the adverse effects of extrac- tion height on pillars.

关键词： Thick coal seamSingle lift depillaring of total thicknessCSmIT)Extraction heightPillar instabilityCaving of coal

Sustainable Integrated Inventory Model for Substitutable Deteriorating Items Considering Both Transport and Industry Carbon Emissions

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Journal of Systems Science and Systems Engineering 2022年第3期31卷 267-287页

作者： Ranu singh Vinod kumar Mishra Department of Mathematics and Scientific Computing Madan Mohan Malaviya University of TechnologyGorakhpur-273010U.P.India

Sustainable integrated inventory management policy focuses on reducing the environmental impact of the manufacturing and transport *** study develops an integrated single-manufacturer single-buyer inventory model for substitutable deteriorating items considering transport and industry carbon *** article categorizes carbon emissions into two parts:direct and indirect *** also assume two mutually substitutable items,and substitution is considered on the buyer's *** one of the items is out of stock,the demand for that item can be partially satisfied by the stock of the other item;else,demand will be *** purpose of this study is to minimize the integrated cost of the supply chain with total carbon emissions produced by industry and transport sectors and to determine the optimal number of deliveries,order level and carbon emission quantity.A solution procedure is developed to find the optimal values of the *** experiments and sensitivity analyses are presented to demonstrate the proposed model.

关键词： Integrated inventory model sustainability deteriorating items substitutable items carbon emission