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Recent advances in catalytic combustion of AP-based composite solid propellants

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Defence Technology（防务技术） 2021年第3期17卷 1013-1031页

作者： Narendra Yadav prem kumar Srivastava Mohan Varma Department of Space Engineering&Rocketry India Department of Chemistry Birla Institute of TechnologyMesraRanchiIndia

Composite solid propellants(CSPs) have widely been used as main energy source for propelling the rockets in both space and military applications. Internal ballistic parameters of rockets like characteristic exhaust velocity, specific impulse, thrust, burning rate etc., are measured to assess and control the performance of rocket motors. The burn rate of solid propellants has been considered as most vital parameter for design of solid rocket motors to meet specific mission requirements. The burning rate of solid propellants can be tailored by using different constituents, extent of oxidizer loading and its particle size and more commonly by incorporating suitable combustion catalysts. Various metal oxides(MOs),complexes, metal powders and metal alloys have shown positive catalytic behaviour during the combustion of CSPs. These are usually solid-state catalysts that play multiple roles in combustion of CSPs such as reduction in activation energy, enhancement of rate of reaction, modification of sequences in reaction-phase, influence on condensed-phase combustion and participation in combustion process in gas-phase reactions. The application of nanoscale catalysts in CSPs has increased considerably in recent past due to their superior catalytic properties as compared to their bulk-sized counterparts. A large surface-to-volume ratio and quantum size effect of nanocatalysts are considered to be plausible reasons for improving the combustion characteristics of propellants. Several efforts have been made to produce nanoscale combustion catalysts for advanced propellant formulations to improve their energetics. The work done so far is largely scattered. In this review, an effort has been made to introduce various combustion catalysts having at least a metallic entity. Recent developments of nanoscale combustion catalysts with their specific merits are discussed. The combustion chemistry of a typical CSP is briefly discussed for providing a better understanding on role of co

关键词： Composite solid propellants Burn rate modifier Metallic nano-catalysts Catalytic combustion Thermal decomposition

Proximate Composition,Mineral Content and Fatty Acids Analyses of Aromatic and Non-Aromatic Indian Rice

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Rice science 2017年第1期24卷 21-31页

作者： Deepak kumar VERMA prem Prakash SRIVASTAV Agricultural and Food Engineering Department Indian Institute of TechnologyKharagpur 721302India

Awareness on nutritive value and health benefits of rice is of vital importance in order to increase the consumption of rice in daily diet of the human beings. In this study, a total of six aromatic and two non-aromatic rice accessions grown in India were analysed for their nutritional quality attributes including proximate composition, mineral contents and fatty acids. Data with three replications were used to measure Pearson＇s simple correlation co-efficient in order to establish the relationship among various nutritional quality attributes. The result on proximate composition showed that Govind Bhog had the highest moisture（13.57%） and fat（0.92%） content, which signifies its tasty attribute. Badshah Bhog exhibited the highest fibre content（0.85%）, carbohydrate content（82.70%） and food energy（365.23 k Cal per 100 g）. Among the minerals, the higher Ca（98.75 mg/kg）, Zn（17.00 mg/kg） and Fe（31.50 mg/kg） were in Gopal Bhog, whereas the highest Na（68.85 mg/kg） was in Badshah Bhog, the highest k（500.00 mg/kg） was in Swetganga, khushboo and Sarbati. The highest contents of unsaturated fatty acids viz. oleic acid（49.14%）, linoleic acid（46.99%） and linolenic acid（1.27%） were found in Sarbati, whereas the highest content of saturated fatty acids viz. myristic acid（4.60%） and palmitic acid（31.91%） were found in Govind Bhog and stearic acid（6.47%） in Todal. The identified aromatic rice accessions Gopal Bhog, Govind Bhog and Badshah Bhog and non-aromatic rice accession Sarbati were found nutritionally superior among all eight tested accessions. The nutritional quality oriented attributes in this study were competent with recognized prominent aromatic and non-aromatic rice accessions as an index of their nutritional worth and recommend to farmers and consumers which may be graded as export quality rice with good unique nutritional values in international market.

关键词： aromatic unsaturated nutritional proximate accession carbohydrate oleic vital competent attribute

Data with Non-Euclidean Geometry and Its Characterization

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Journal of Artificial Intelligence and Technology 2022年第1期2卷 3-8页

作者： prem kumar Singh Department of Computer Science and Engineering Gandhi Institute of Technology and Management-VisakhapatnamIndia

Recently,dealing with the non-Euclidean data and its characterization is considered as one of the major issues by *** first problem arises while defining the distinction among Euclidean and non-Euclidean geometry with its *** second problem arises while dealing with the non-Euclidean geometry in true,false,and uncertain *** third problem arises while investigating some patterns in non-Euclidean data *** paper focused on tackling these issues with some real-life examples in data processing,data visualization,knowledge representation,and quantum computing.

关键词： anisotropy Euclidean geometry heteroclinic orbit knowledge representation many-valued attributes non-Euclidean geometry

Four-Way Turiyam Set-Based Human Quantum Cognition Analysis

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Journal of Artificial Intelligence and Technology 2022年第4期2卷 144-151页

作者： prem kumar Singh Department of Computer Science and Engineering Gandhi Institute of Technology and Management-VisakhapatnamAndhra Pradesh 530045India

Recently, the Turiyam set was introduced for characterization of data sets beyond true, false, and uncertain regionsbased on human cognition. This set is able to represent the unknown, undefined, or conduit metaphor of human quantumcognition precisely. One of the suitable examples is USA–Russia conflicts or Cold war is beyond the characterization of win,draw, or loss. It is totally based on the conduit metaphor of USA and Russia. In this case, a set of countries that may supportRussia (Sr) can be characterized as true regions. A set of countries that does not support Russia (i.e., supporting the USA) can becharacterized as false regions (Su). There is also a set of countries that supports both Russia–USA based on the given *** types of countries and their vote are uncertain. The fourth case is some countries like India, China, and UAE that choosenothing to fulfill their conduit metaphor. It is called Turiyam or four-dimension cognition. The characterization of this typeof four-dimension Turiyam cognition and its representation is one of the crucial tasks for data science researchers. It is indeed arequirement to understand the human quantum cognition and its conduit metaphor. To tackle this issue, the current paper will tryto introduce a method for characterization of this undefined, unknown, or Turiyam cognition via a defined interval set. Theobjective is to provide a way to explore them in known graph (t), not known graph (f), partial graph (i), or unknown graph (l) withan example.

关键词： fourth dimensions knowledge representation non-Euclidean Quaternion Turiyam set unknown

A New High Performance Realization of Hyperchaotic Modified Canonical Chua Circuit Using JFETs

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Chinese Physics Letters 2008年第8期25卷 2803-2805页

作者： prem Bhushan Mital Umesh kumar R.S. Prasad IEC College of Engineering and Technology GB Nagar Pin-201 306 India Indian Institute of Technology Delhi Pin-110016 India Inderprastha Eng. College Sahibabad Ghaziabad (UP) India

A new implementation of hyperchaotic modified canonical Chua circuit using junction field-effect transistors （JFETs） is proposed. The design is based on a source coupled JFET circuit to approximate a smooth cubic nonlinearity and a two-terminal negative resistance element containing a p-n-p silicon transistor and an n-channel JFET. The realization is supported by Orcad Pspice simulation and numerical MATLAB results. The hyperchaotic nature is confirmed by two positive Lyapunov exponents associated with the attractor which is a fractal with a Lyapunov dimension between 3 and 4.

关键词： OSCILLATOR

Experimental investigation into the effects of Argemone biodiesel/diesel blends on cyclic variations in a multi-cylinder CRDI engine

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Clean Energy 2023年第2期7卷 363-374页

作者： Abhinav Sharma prem kumar Sarbjot Singh Sandhu Mandeep Singh Department of Mechanical Engineering Dr B R Ambedkar National Institute of TechnologyJalandhar-144011PunjabIndia

Internal combustion engines suffer from high cyclic variations that result in higher emissions,lower efficiency,higher fuel consump-tion and poor *** purpose of this study is to investigate how Argemone mexicana biodiesel(AGB)/diesel blended fuels affect the cyclic variability of combustion parameters such as maximum cylinder pressure(Pmax)and indicated mean effective pressure(IMEP)in a four-cylinder turbocharged intercooled common-rail direct injection engine under various engine loading *** chemical and physical properties of AGB produced from *** oil were measured and compared according to the ASTM D6751 *** various volumetric ratios,AGB and diesel fuel were blended as D100,AB10(10%AGB+90%D100),AB20(20%AGB+80%D100)and AB30(30%AGB+70%D100).The IMEP and Pmax time-series data were collected over 200 consecutive cycles at low,partial and high engine loads at a constant engine speed of 2000 *** coefficients of variation(COV)of combustion parameters(Pmax and IMEP)were measured for different AGB/diesel blends and found to be within acceptable *** results show that COV_(Pmax) and COV_(IMEP) decrease as the engine load *** was observed that at low load,AB10 has the lowest COV(Pmax,IMEP),and at partial and high load,AB20 has the lowest COV(Pmax,IMEP)among all the blends.

关键词： indicated mean effective pressure cyclic variations biodiesel diesel engine Argemone mexicana biodiesel

Structural build-up model for three-dimensional concrete printing based on kinetics theory

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 998-1014页

作者： Prabhat Ranjan prem P.S.AMBILY Shankar kumar Greeshma GIRIDHAR Dengwu JIAO Advanced Materials Laboratory CSIR-Structural Engineering Research CentreChennai 600113India Department of Architecture and Civil Engineering City University of Hong KongHong Kong 999077China

The thixotropic structural build-up is crucial in extrusion-based three-dimensional(3D)concrete *** paper uses a theoretical model to predict the evolution of static and dynamic yield stress for printed *** model employs a structural kinetics framework to create a time-independent constitutive link between shear stress and shear *** model considers flocculation,deflocculation,and chemical hydration to anticipate structural *** reversible and irreversible contributions that occur throughout the build-up,breakdown,and hydration are defined based on the proposed structural ***,detailed parametric studies are conducted to evaluate the impact of model *** is revealed that the proposed model is in good agreement with the experimental results,and it effectively characterizes the structural build-up of 3D printable concrete.

关键词： structural build-up rheology thixotropy 3D printable concrete kinetics theory ultra high performance concrete

Metaheuristics with Optimal Deep Transfer Learning Based Copy-Move Forgery Detection Technique

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Intelligent Automation & Soft Computing 2023年第1期35卷 881-899页

作者： C.D.prem kumar S.Saravana Sundaram Department of Information Technology Hindusthan College of Engineering and TechnologyCoimbatore641032TamilnaduIndia Department of Electrical and Electronics Engineering Hindusthan College of Engineering and TechnologyCoimbatore641032TamilnaduIndia

The extensive availability of advanced digital image technologies and image editing tools has simplified the way of manipulating the image *** effective technique for tampering the identification is the copy-move *** image processing techniques generally search for the patterns linked to the fake content and restrict the usage in massive data ***-ingly,deep learning(DL)models have demonstrated significant performance over the other statistical *** this motivation,this paper presents an Optimal Deep Transfer Learning based Copy Move Forgery Detection(ODTL-CMFD)*** presented ODTL-CMFD technique aims to derive a DL model for the classification of target images into the original and the forged/tampered,and then localize the copy moved *** perform the feature extraction process,the political optimizer(PO)with Mobile Networks(MobileNet)model has been derived for generating a set of useful ***,an enhanced bird swarm algorithm(EBSA)with least square support vector machine(LS-SVM)model has been employed for classifying the digital images into the original or the forged *** utilization of the EBSA algorithm helps to properly modify the parameters contained in the Multiclass Support Vector Machine(MSVM)technique and thereby enhance the classification *** ensuring the enhanced performance of the ODTL-CMFD technique,a series of simulations have been performed against the benchmark MICC-F220,MICC-F2000,and MICC-F600 *** experimental results have demonstrated the improvised performance of the ODTL-CMFD approach over the other techniques in terms of several evaluation measures.

关键词： Copy move detection image forgery deep learning machine learning parameter tuning forensics

Tuning the particle size and morphology of high energetic material nanocrystals

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Defence Technology（防务技术） 2015年第4期11卷 382-389页

作者： Raj kumar prem Felix SIRIL Pramod SONI School of Basic Sciences and Advanced Materials Research Centre Indian Institute of Technology Mandi Terminal Ballistics Research Laboratory

Morphology controlled synthesis of nanoparticles of powerful high energetic compounds(HECs) such as l,3,5-trinitro-l,3,5-triazinane(RDX) and 1,3,5,7-tetranitro-l,3,5,7-tetrazocane(HMX) were achieved by a simple solvent—antisolvent interaction(SAI) method at 70 ℃.The effects of different solvents on particle size and morphology of the prepared nano-HECs were studied *** size and morphology of the nano-HECs was characterized using field emission scanning electron microscopy(FE-SEM) imaging.X-ray diffraction(XRD) and Fourier transform infrared(FTIR) spectroscopy studies revealed that RDX and HMX were precipitated in their most stable polymorphic forms,i.e.a and P,*** analysis coupled with differential scanning calorimetry(TGA-DSC) studies showed that the thermal response of the nanoparticles was similar to the respective *** nanoparticles with spherical and rod shaped morphology were observed under different solvent *** mean particle size also varied considerably with the use of different solvents.

关键词：平均粒径高含能材料形貌纳米晶体场发射扫描电子显微镜差示扫描量热法纳米颗粒纳米粒子