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Studies on the Internal Ballistics of Composite Solid Rocket Propellants Incorporating Nano-Structured Catalysts

Advances in Aerospace Science and Technology 2017年第4期2卷 48-72页

作者： Mukesh R. Sivasubramaniyam R. Elangovan R. R. Abhinaya Sree R. Harish R. Rajashree D. satish kumar kanhar Department of Aeronautical Engineering A.C.S College of Engineering Bangalore India Department of Mechanical Engineering A.C.S College of Engineering Bangalore India

This paper deals with the analysis of burn rate using various catalysts of Iron Oxide and determining which gives the higher burn rate with low pressure variation. The Ammonium Perchlorate (AP) was obtained and ground into fine powder with the particle size ranging from 63 to 125 μm. The propellant strands were prepared with proportions by mixing AP with the binder (Hydroxyl Terminated Polybutadiene), the catalyst (Iron Oxide), curing agent (Isophorone diisocyanate) and the plasticizer (Dioctyladipate). The prepared propellant mixture was cured at around 63 deg C to get various propellant strands. The first strand was prepared with the absence of a catalyst to set an initial base of comparison with other Iron Oxide catalysts, namely, Flower Shaped, Micro and Nano, based on the size of the particles. The combustion process was carried out in a strand burner, which was in turn connected to a data acquisition system. The obtained output was analysed in the form of graphs. The burn rate was achieved by calculating the slope of the graph i.e . by calculating the difference between the highest and the lowest peak of the graph and dividing the total time by the answer. The experiment was repeated with the different catalyst types, as mentioned above, at different pressures. It was observed that the Nano shaped Iron Oxide exhibits better burning characteristics when compared to the rest with the pressure index of 0.792. In this paper, the various experiments carried out along with their procedures are explained in detail. The results obtained and the techniques used are also elaborately described in this paper.

关键词： Ammonium Perchlorate Dioctyladipate Hydroxyl Terminated

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Effect of cooling media on bead geometry,microstructure,and mechanical properties of wire arc additive manufactured IN718 alloy

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Advances in Manufacturing 2024年第1期12卷 124-149页

作者： Parveen kumar satish kumar Sharma Ratnesh kumar Raj Singh Department of Mechanical Engineering Thapar Institute of Engineering and TechnologyPatialaPunjab147004India

This work aims to present and explore thermal management techniques for the wire arc additive manufacturing(WAAM)of IN718 components.Excessive heat can be mitigated via air or water cooling.In this study,the material was deposited under four different heat-input conditions with air or water cooling.In air cooling,the layer is deposited in a normal atmospheric air environment,whereas with water cooling,the material is deposited inside a water tank by varying the water level.To validate the air and water cooling thermal management techniques,IN718 single-pass and multilayer linear walls were deposited using the bidirectional gas metal arc welding based WAAM setup under four different heat input conditions.During the deposition of single layers,the temperature profiles were recorded,and the geometric and microstructural features were explored.For multilayer wall structures,the mechanical properties(hardness,tensile strength,and elongation)were determined and assessed using the corresponding microstructural features explored through scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and electron backscatter diffraction(EBSD)analyses.The microstructure observed through SEM analysis in the building direction was found to be nonhomogenous compared with that in the deposition direction.Moreover,water cooling was found to govern bead characteristics,such as wall width and height.The grain size and anisotropy of the mechanical properties also decreased in the water-cooled case.Hence,water cooling is an economical and efficient method to mitigate excessive heat accumulation in WAAM-deposited IN718.

关键词： Air cooling Water cooling IN718 Bead characteristics Microstructure Electron backscatter diffraction(EBSD)

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Genomic selection of eight fruit traits in pear

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Horticultural Plant Journal 2024年第2期10卷 318-326页

作者： Manyi Sun Mingyue Zhang satish kumar Mengfan Qin Yueyuan Liu Runze Wang Kaijie Qi Shaoling Zhang Wenjing Chang Jiaming Li Jun Wu College of Horticulture State Key Laboratory of Crop Genetics&Germplasm Enhancement and UtilizationNanjing Agricultural UniversityNanjingJiangsu 210095China State Key Laboratory of Crop Biology College of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandong 271018China The New Zealand Institute for Plant and Food Research Limited Private Bag 1401Havelock North 4157New Zealand Zhongshan Biological Breeding Laboratory NanjingJiangsu 210014China

Genomic selection (GS) has the potential to improve selection efficiency and shorten the breeding cycle in fruit tree breeding. In this study,we evaluated the effect of prediction methods, marker density and the training population (TP) size on pear GS for improving its performance and reducing cost. We evaluated GS under two scenarios:(1) five-fold cross-validation in an interspecific pear family;(2) independent validation. Based on the cross-validation scheme, the prediction accuracy (PA) of eight fruit traits varied between 0.33 (fruit core vertical diameter)and 0.65 (stone cell content). Except for single fruit weight, a slightly better prediction accuracy (PA) was observed for the five parametrical methods compared with the two non-parametrical methods. In our TP of 310 individuals, 2 000 single nucleotide polymorphism (SNP) markers were sufficient to make reasonably accurate predictions. PAs for different traits increased by 18.21%-46.98%when the TP size increased from 50to 100, but the increment was smaller (-4.13%-33.91%) when the TP size increased from 200 to 250. For independent validation, the PAs ranged from 0.11 to 0.45 using rrBLUP method. In summary, our results showed that the TP size and SNP numbers had a greater impact on the PA than prediction methods. Furthermore, relatedness among the training and validation sets, and the complexity of traits should be considered when designing a TP to predict the test panel.

关键词： Pear Pyrus Prediction method TP size SNP marker number

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Jensen-Renyi’s-Tsallis Fuzzy Divergence Information Measure with its Applications

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Communications in Mathematics and Statistics 2022年第3期10卷 451-482页

作者： Ratika Kadian satish kumar Department of Mathematics Maharishi Markandeshwar(Deemed to be)UniversityMullana-Ambala 133207India

In this paper,we have characterized the sum of two general measures associated with two distributions with discrete random variables.One of these measures is logarithmic,while others contains the power of variables,named as joint representation of Renyi’s-Tsallis divergence measure.Then,we propose a divergence measure based on Jensen-Renyi’s-Tsallis entropy which is known as a Jensen-Renyi’s-Tsallis divergence measure.It is a generalization of J-divergence information measure.One of the silent features of this measure is that we can allot the equal weight to each probability distribution.This makes it specifically reasonable for the study of decision problems,where the weights could be the prior probabilities.Further,the idea has been generalized from probabilistic to fuzzy similarity/dissimilarity measure.Besides the validation of the proposed measure,some of its key properties are also studied.Further,the performance of the proposed measure is contrasted with some existing measures.At last,some illustrative examples are solved in the context of clustering analysis,financial diagnosis and pattern recognition which demonstrate the practicality and adequacy of the proposed measure between two fuzzy sets(FSs).

关键词： Fuzzy sets Divergence measure Similarity measure Clustering analysis Financial diagnosis

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Survey on recent advances in IoT application layer protocols and machine learning scope for research directions

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Digital Communications and Networks 2022年第5期8卷 727-744页

作者： Praveen kumar Donta satish Narayana Srirama Tarachand Amgoth Chandra Sekhara Rao Annavarapu Department of Computer Science and Engineering Indian Institute of Technology(Indian School of Mines)Dhanbad826004India School of Computer and Information Sciences University of HyderabadHyderabad500046India Mobile&Cloud Lab Institute of Computer ScienceFaculty of Science and TechnologyUniversity of Tartu50090Estonia

The Internet of Things(IoT)has been growing over the past few years due to its flexibility and ease of use in real-time applications.The IoT's foremost task is ensuring that there is proper communication among different types of applications and devices,and that the application layer protocols fulfill this necessity.However,as the number of applications grows,it is necessary to modify or enhance the application layer protocols according to specific IoT applications,allowing specific issues to be addressed,such as dynamic adaption to network conditions and interoperability.Recently,several IoT application layer protocols have been enhanced and modified according to application requirements.However,no existing survey articles focus on these protocols.In this article,we survey traditional and recent advances in IoT application layer protocols,as well as relevant real-time applications and their adapted application layer protocols for improving performance.As changing the nature of protocols for each application is unrealistic,machine learning offers means of making protocols intelligent and is able to adapt dynamically.In this context,we focus on providing open challenges to drive IoT application layer protocols in such a direction.

关键词： Internet of things Machine learning Application layer Request-response protocols Publish-subscribe protocols

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2.0 Ga orogenic graphite deposits and associated 13C-enriched meta-carbonate rocks from South China Craton:Implications for global Lomagundi event

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Geoscience Frontiers 2022年第4期13卷 181-192页

作者： Yihe Li Madhusoodhan satish-kumar Sasidharan Kiran Chuanhui Wan Jianping Zheng Institute of Geophysics and Geomatics Hubei Subsurface Multi-scale Imaging Key LaboratoryChina University of GeosciencesWuhan 430074China Department of Geology Faculty of ScienceNiigata UniversityNiigata 950-2181Japan Graduate School of Science and Technology Niigata UniversityNiigata 950-2181Japan Eighth Geological Brigade of Hubei Xiangyang 441000China School of Earth Sciences State Key Laboratory of Geological Processes and Mineral ResourcesChina University of GeosciencesWuhan 430074China

The Lomagundi(-Jatuli)event,characterized by extremely high positive global inorganic carbon isotope excursion at about 2.2 billion years ago,is pivotal in investigating the causes and consequences of great oxygenation event,inventory and sequestration of carbon on the Earth’s surface,evolution of life,and more profoundly tectonic control on Earth’s environment.However,the reasons that caused the isotopic excursion are not resolved yet.Herein,we report the discovery of meta-carbonate rocks with distinct positive carbon isotopic excursion from the Paleoproterozoic continental collision zone of the Kongling Complex,South China Craton.The δ^(13)C_(V-PDB) values for meta-carbonate rocks show positive values in the range from+5.5‰to+11.6‰,whereas the δ^(13)C_(V-PDB) values of associated graphite deposits range from-25.8‰to-9.5‰.Zircon U-Pb-Hf isotopes from zircon-bearing meta-carbonate sample yielded weighted average _(207)Pb/_(206)Pb age of 2001.3±9.5 Ma,with correspondingε_(Hf)(t)range from-7.05 to-3.16,comparable to the values of local 2.9–2.6 Ga basement rocks.Geochemical characteristics of meta-carbonate rocks,such as their rare earth element patterns and the trace element parameters of La,Ce,Eu,and Gd anomalies and Y/Ho ratio,suggest that the carbonate deposition took place in passive continental margin in association with large volumes of organic carbon.The extensive graphite deposits from Kongling Complex in South China Craton,their equivalents in the North China Craton and elsewhere across the globe prove that the burial of ^(12)C-enriched organic carbon has eventually resulted in the global enrichment of ^(13)C in the atmospheric CO_(2),which is recorded in the marine carbonate rocks.Isotopic mass balance estimates indicate that more than half of the organic carbon was buried during the oceanic closure.Hence,the observed global shift could be directly related to the continent collision event in greater China,thus resolving the long-standing paradox of the Lomagundi global positive carbon isotope excursion.Mo

关键词： Positive carbon isotope excursion Lomagundi(-Jatuli)event Kongling Complex South China Craton Marine carbonate

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Assessment of geodetic strain and stress variations in Nepal due to 25 April 2015 Gorkha earthquake:Insights from the GNSS data analysis and b-value

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Geodesy and Geodynamics 2022年第3期13卷 288-300页

作者： Sravanthi Gunti Priyom Roy J.Narendran Ramesh Pudi S.Muralikrishnan K.Vinod kumar M.Subrahmanyam Y.Israel B.satish kumar National Remote Sensing Centre Indian Space Research Organization(ISRO)BalanagarHyderabad500037India Sustainability Risk Management Solutions of IndiaNoida201301India Department of Geophysics Andhra UniversityVisakhapatnam530003India

A magnitude M;7.8 earthquake occurred on 25 April 2015(referred as Gorkha earthquake).We have analyzed the spatial variation of b-value and two-dimensional strain within Nepal Himalaya before and after the Gorkha earthquake.We have used continuous Global Navigation Satellite System(GNSS)data from 30 stations in the Nepal region for geodetic strain estimation and earthquake data for b-value estimation.The GNSS data were processed using double differencing technique for the accurate position of each station.The precise velocity vectors show a general azimuth of north east for all the stations and have been used to derive two-dimensional strain.Between epicenters of Gorkha(25 April 2015)and Dolakha earthquakes(12 May 2015),we observed high co-seismic horizontal displacements(0.2 m to 2 m).In the Pre-seismic deformation study,maximum strain accumulation(56.40×10;)and low bvalue(0.79-0.89)was observed in and around the Western Nepal region,which may be responsible for the 2015 Gorkha earthquake.The potential seismic zones were identified by GIS based integration of geodetic strain and b-value map and superimposition using weighted overlay method.The Maximum strain and low b-value are now observed in the eastern part of Nepal.Hence,the spatial disposition of elastic energy has changed after the two major earthquakes and continuous seismic hazard assessment is required in the eastern Nepal.

关键词： Himalaya Co-seismic offsets Bernese 5.2 UNAVCO Grid_Strain

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Numerical investigation of the effect of transitory strand opening on mixing in a multistrand tundish

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 535-542页

作者： Sabin kumar Mishra Pradeep kumar Jha satish Chandra Sharma satish kumar Ajmani Department of Mechanical and Industrial Engineering Indian Institute of Technology RoorkeeRoorkee 247667UttarakhandIndia Steelmaking and Casting Research Group Tata SteelR&DBurma MinesJamshedpur 831007JharkhandIndia

In a multistrand,the outlet near the inlet produces short circuiting flow.This leads to the formation of dead zones inside the tundish,and consequently,the mean residence time decreases.In the present study,numerical investigation of mixing inside a delta shaped tundish with sloping boundaries was carried out by solving the Navier-Stokes equation and employing the standard turbulence model.To decrease the dead zone volume inside the tundish,the effect of closing the outlet near the inlet for a small amount of time and further opening it on the mixing behavior of the tundish was studied.The outlets near the inlet were closed for varying amount of time,and the transient analysis of fluid flow and the tracer dispersion study were carried out to find the mixing parameters of the tundish,namely,mean residence time and the ratio of mixed to dead volume of the tundish.An optimum closure time of the near outlet has been found,which yields best mixing inside the tundish.The numerical code was validated against the experimental observation by performing the tracer dispersion study inside a multistrand tundish and the reasonably good match between the experimental and numerical results in terms of residence time distribution （RTD） curves.The results obtained from the present study confirm the strong role of choosing the right time for opening and closing the outlets to get improved characteristics for the fluid flow and mixing behavior of the tundish.The educational version of computational fluid dynamics （CFD） software PHOENICS was used to solve the governing equations and interpret the results in different forms.

关键词： continuous casting billets tundish flow simulation mean residence time dead volume computational fluid dynamics （CFD）

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Optimal integration of DGs into radial distribution network in the presence of plug-in electric vehicles to minimize daily active power losses and to improve the voltage profile of the system using bioinspired optimization algorithms

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Protection and Control of Modern Power Systems 2020年第1期5卷 21-35页

作者： satish kumar Injeti Vinod kumar Thunuguntla Department of Electrical Engineering National Institute of Technology WarangalTelengana State 506004India

Purpose:The increase in plug-in electric vehicles(PEVs)is likely to see a noteworthy impact on the distribution system due to high electric power consumption during charging and uncertainty in charging behavior.To address this problem,the present work mainly focuses on optimal integration of distributed generators(DG)into radial distribution systems in the presence of PEV loads with their charging behavior under daily load pattern including load models by considering the daily(24 h)power loss and voltage improvement of the system as objectives for better system performance.Design/methodology/approach:To achieve the desired outcomes,an efficient weighted factor multi-objective function is modeled.Particle Swarm Optimization(PSO)and Butterfly Optimization(BO)algorithms are selected and implemented to minimize the objectives of the system.A repetitive backward-forward sweep-based load flow has been introduced to calculate the daily power loss and bus voltages of the radial distribution system.The simulations are carried out using MATLAB software.Findings:The simulation outcomes reveal that the proposed approach definitely improved the system performance in all aspects.Among PSO and BO,BO is comparatively successful in achieving the desired objectives.Originality/value:The main contribution of this paper is the formulation of the multi-objective function that can address daily active power loss and voltage deviation under 24-h load pattern including grouping of residential,industrial and commercial loads.Introduction of repetitive backward-forward sweep-based load flow and the modeling of PEV load with two different charging scenarios.

关键词： Plug-in electric vehicles(PEVs) Distributed generators(DGs) Repetitive distribution power flow Particle swarm optimization algorithm(PSO) Butterfly optimization(BO) Daily active power loss

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A Hybrid Offline-Online Approach to Adaptive Downlink Resource Allocation Over LTE

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 766-777页

作者： satish kumar Rajesh Devaraj Arnab Sarkar IEEE the Department of Computer Science and Engineering IIT Guwahati

Radio resource management mechanisms in current and future wireless networks is expected to face an enormous challenge due to the ever increasing demand for bandwidth and latency sensitive applications on mobile devices. This is because an optimal resource allocation scheme which attempts to multiplex the available bandwidth in order to maximize Quality of service(QoS), will pose an exponential computational burden at eNodeB. In order to minimize such computational overhead, this work proposes a hybrid offline-online resource allocation strategy which effectively allocates all the available resources among flows such that their QoS requirements are satisfied. The flows are firstly classified into priority buckets based on real-time criticality factors. During the offline phase, the scheduler attempts to maintain the system load within a pre-specified safe threshold value by selecting an appropriate number of buckets. This offline selection procedure makes use of supervisory control theory of discrete event systems to synthesize an offline scheduler. Next, we have devised an online resource allocation strategy which runs on top of the offline policy and attempts to minimize the impact of the inherent variability in wireless networks. Simulation results show that the proposed scheduling framework is able to provide satisfactory QoS to all end users in most practical scenarios.

关键词： Discrete event systems (DES) hybrid scheduling long term evolution (LTE) quality of service (QoS) radio resource management supervisory control

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