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Journal of Bionic Engineering 2023年第4期20卷 1737-1746页

作者： Ankit Samal Sanjeev kumar Manish Bhargava Barnik Saha Roy Mechanical Engineering Department National Institute of Technology AgartalaJiraniaTripura799046India Mechanical Engineering Department Subharti Institute of Technology and EngineeringMeerutUttar Pradesh250005India

Natural fibre-reinforced composites are now becoming incredibly common in various products because of their comparable qualities to conventional materials.Due to its availability,superior mechanical qualities,and low cost,banana pseudostem is extensively used in various applications requiring natural fibres.This study investigates the physical and mechanical properties of epoxy composites reinforced with banana pseudostem fibres that contain Al_(2)O_(3) particulate.In order to produce composites with fibre and filler loadings,manual hand layup was used.Fibre and filler loading effects on composite properties were studied in experiments.The results of the investigations demonstrate that proportion of Al_(2)O_(3) in composites significantly influences their mechanical and physical properties.Additionally,the composite with a fibre content of 30%shows improved mechanical proportions and hardness.Thermogravimetric analysis was used to study the composite's thermal behaviour.Composites are more thermally stable than raw epoxy.Fourier Transform Infrared Spectroscopy and Scanning electron microscopy analyses were used to characterize the composites.

关键词： Banana Pseudostem fibre Al_(2)O_(3) Epoxy Characterization Mechanical properties

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 network.Recently, diverse steganography techniques using edge identification have been proposed in literature.Numerous 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

Exploring the potential of artificial intelligence techniques in prediction of the removal efficiency of vortex tube silt ejector

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International Journal of Sediment Research 2023年第4期38卷 615-627页

作者： Sanjeev kumar Chandra Shekhar Prasad Ojha Nand kumar Tiwari Subodh Ranjan Department of Civil Engineering Indian Institute of Technology Department of Civil Engineering National Institute of Technology

A vortex tube silt ejector is a curative hydraulic structure used to remove sediment deposits from canals and is recognized as one of the most efficient substitutes for physically removing canal sediment. The spatially varied flow in the channel and the rotational flow behavior in the tube make the silt removal process complex. It is even harder to accurately predict the silt removal efficiency by traditional models accurately. However, artificial intelligence(AI) and machine learning approaches have emerged as robust substitutes for studying complex processes. Therefore, this research makes use of AI approaches; support vector machine(SVM), random forest(RF), random tree(RT), and multivariate adaptive regression spline(MARS) to compute the vortex tube silt ejection efficiency using the laboratory data sets. The outcomes of the artificial intelligence(AI)-based techniques also were compared with traditional models. It was found that the RT model(root mean square error, RMSE = 2.165, Nash Sutcliffe efficiency, NSE = 0.98) outperforms the other applied approaches which had relatively more significant result errors. The sensitivity analysis of the process depicts the extraction ratio as the key parameter in the computation of vortex tube silt ejector removal efficiency. The findings of the AI-based approaches discussed in the current study might be helpful for hydraulic engineers as well as researchers in the assessment of the removal efficiency of vortex tube silt ejectors.

关键词： Vortex tube silt ejector Support vector machine Random forest Random tree Multivariate adaptive regression spline

Quantization error in stereo imaging system with noise distributions

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第5期11卷 86-117页

作者： Deepika Saini Sanjeev kumar Department of Mathematics Graphic Era Deemed to be University Dehradun Uttarakhand 248002India Department of Mathematics Indian Institute of Technology Roorkee Roorkee 247667India

The problem of estimating quantization error in 2D images is an inherent problem in computer vision.The outcome of this problem is directly related to the error in reconstructed 3D position coordinates of an object.Thus estimation of quantization error has its own importance in stereo vision.Although the quantization error cannot be controlled fully,still statistical error analysis helps us to measure the performance of stereo systems that relies on the imaging parameters.Generally,it is assumed that the quantization error in 2D images is distributed uniformly that need not to be true from a practical aspect.In this paper,we have incorporated noise distributions(Triangular and Trapezoidal)for the stochastic error analysis of the quantization error in stereo imaging systems.For the validation of the theoretical analysis,the detailed simulation study is carried out by considering different cases.

关键词： Quantization error stereo images noise distributions range estimation error range error magnitude relative range error

Water and sediment geochemistry of an urban lake: Implications to weathering and anthropogenic activity

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International Journal of Sediment Research 2022年第6期37卷 809-822页

作者： Mohammad Saleem Ghulam Jeelani Ishfaq Ahmad Pall Javid Ganai Sanjeev kumar Department of Geology and Mining Government of Jammu and Kashmir Department of Earth Sciences University of Kashmir Physical Research Laboratory

Lakes are sensitive ecosystems and respond quickly to any natural or anthropogenic contamination,particularly in urban areas due to poor planning and mismanagement in urban settlement, encroachment, and anthropogenic pollution. In the current study, water and sediment geochemistry are used along with available time series of geospatial data sets to assess: a) provenance and sources of pollution in the lake sediment and water, b) health risk using various sediment and water quality indices, and c)the key drivers of lake shrinkage. Chemical index of alteration(CIA) of lake sediment is higher(>85) with an atypical cluster of samples(CIA 50-75) towards the south and west of the lake. Further, samples in this cluster show granodioritic provenance which is contrary to the overall mafic provenance of lake sediment. The unusual decrease in CIA in the southern and western side of the lake is attributed to anthropogenically induced fresh sediment in the lake. The results indicate that the sediment is highly polluted by cadmium(Cd) and moderately polluted by copper(Cu), molybdenum(Mo), lead(Pb), and boron(B). Higher Metal Index(MI) values for most of the water samples(>70%) and Hazard Index(HI) for chromium(Cr), nickel(Ni), and cadmium(Cd) towards west and south of the lake reflect the deterioration of water quality in the lake. Moreover, land use change detection attained from available time series of geospatial data sets indicate a drastic transformation of the open water area into other land use classes particularly human settlement, shrinking the lake open water area by 13 km~2 since 1859. The current study will help policy makers and managers to restore and conserve the lake.

关键词： Lake sediment Trace elements Pollution indices Provenance Anthropogenic sources

Evaluation and analysis of cutting speed, wire wear ratio, and dimensional deviation of wire electric discharge machining of super alloy Udimet-L605 using support vector machine and grey relational analysis

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Advances in Manufacturing 2018年第2期6卷 225-246页

作者： Somvir Singh Nain Dixit Garg Sanjeev kumar Department of Mechanical Engineering National Institute of Technology Kurukshetra 136119 India Department of Mechanical Engineering PEC University of Technology Chandigarh 160012 India

The current study investigates the behavior of wire electric discharge machining （WEDM） of the super alloy Udimet-L605 by employing sophisticated machine learning approaches. The experimental work was designed on the basis of the Taguchi orthogonal L27 array, consid- ering six explanatory variables and evaluating their influ- ences on the cutting speed, wire wear ratio （WWR）, and dimensional deviation （DD）. A support vector machine （SVM） algorithm using a normalized poly-kernel and a radial-basis flow kernel is recommended for modeling the wire electric discharge machining process. The grey rela- tional analysis （GRA） approach was utilized to obtain the optimal combination of process variables simultaneously, providing the desirable outcome for the cutting speed, WWR, and DD. Scanning electron microscope and energy dispersive X-ray analyses of the samples were performed for the confirmation of the results. An SVM based on the radial-basis kernel model dominated the normalized poly- kernel model. The optimal combination of process vari- ables for a mutually desirable outcome for the cutting speed, WWR, and DD was determined as Ton1, Toffa, Ip1, WT3, SV1, and WF3. The pulse-on time is the significant variable influencing the cutting speed, WWR, and DD. The largest percentage of copper （8.66%） was observed at the highest cutting speed setting 7.05% of copper at the low of the machine compared to cutting speed setting of the machine.

关键词： Support vector machine （SVM） Greyrelational analysis （GRA） Wire electric dischargemachining （WEDM） Udimet-L605 Scanning electronmicroscope （SEM） Wire wear ratio （WWR）

Sudden cardiac death in a case of Crohn's disease with COVID-19: A case report

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Journal of Acute Disease 2022年第3期11卷 123-126页

作者： Neeraj kumar Subhajit Ghosh Abhyuday kumar Sanjeev kumar Prem kumar Departments of Trauma&Emergency All India Institute of Medical SciencesPatnaIndia Departments of Anaesthesiology All India Institute of Medical SciencesPatnaIndia Departments of CTVS All India Institute of Medical SciencesPatnaIndia Departments of Radiology All India Institute of Medical SciencesPatnaIndia

Rationale:The mechanism of sudden cardiac death in COVID-19 can be multifactorial.Cardiac hypersensitivity to 5-ASA therapy leading to myocarditis has been reported in some cases.Cytokine storm syndrome and idiosyncratic reaction with mesalazine use may lead to sudden cardiac death in COVID-19.Use of immunosuppressants in hospitalized COVID-19 patients should be continued with caution,especially in patients with inflammatory bowel disease.Patient’s concern:A 75-year-old man who was tested positive for SARS-CoV-2 was admitted with a history of shortness of breath for the last two days.He was a known case of Crohn’s disease treated with mesalazine.Diagnosis:COVID-19 pneumonia with underlying Crohn’s disease leading to sudden cardiac death.Intervention:Remdesivir,antibiotics,steroids,low molecular weight heparin,tablet zinc,tab vitamin C,and other supportive treatment were started.Because of increased inflammatory markers,itolizumab was given to the patient on the 2nd day.Outcome:On the 5th day of the intensive care unit,the patient complained of sudden chest pain with respiratory distress leading to bradycardia and asystole and could not be resuscitated.Lessons:Causes for sudden cardiac death in COVID-19 pneumonia patients with Crohn’s disease is multifactorial.Although mesalazine may be a safe and effective drug in the management of inflammatory bowel disease,it can induce sytokine strom syndrome and idiosyncratic reactions that could be one of the reasons of sudden cardic death.Therefore,we should be aware of its serious and potentially life-threatening complications,especially in COVID-19 infected patients.

关键词： COVID-19 Sudden cardiac death Chron’s disease

Adaptive Three-phase Estimation of Sequence Components and Frequency Using H∞ Filter Based on Sparse Model

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Journal of Modern Power Systems and Clean Energy 2020年第5期8卷 981-990页

作者： Umamani Subudhi Harish kumar Sahoo Sanjeev kumar Mishra Department of Electronics and Telecommunication Engineering Indian Institute of Information Technology(IIIT)BhubaneshwarIndia Department of Electronics and Telecommunication Engineering Veer Surendra Sai University of Tecnology(Burla)SambalpurIndia

The estimation of sequence or symmetrical components and frequency in three-phase unbalanced power system is of great importance for protection and relay.This paper proposes a new H∞filter based on sparse model to track the sequence components and the frequency of three-phase unbalanced power systems.The inclusion of sparsity improves the error convergence behavior of estimation model and hence short-duration non-stationary PQ events can easily be tracked in the time domain.The proposed model is developed using l1 norm penalty in the cost function of H∞filter,which is quite suitable for estimation across all the three phases of an unbalanced system.This model uses real state space modeling across three phases to estimate amplitude and phase parameters of sequence components.However,frequency estimation uses complex state space modeling and Clarke transformation generates a complex measurement signal from the unbalanced three-phase voltages.The state vector used for frequency estimation consists of two state variables.The proposed sparse model is tested using distorted three-phase signals from IEEE-1159-PQE database and the data generated from experimental laboratory setup.The analysis of absolute and mean square error is presented to validate the performance of the proposed model.

关键词： Sequence component Clarke transformation H∞filter state space model

Effects of the type of forest alteration on gross nitrogen mineralization in soils of southern India

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Journal of Forestry Research 2021年第4期32卷 1689-1697页

作者： Niharika Sharma Sanjeev kumar Geosciences Division Physical Research LaboratoryAhmedabadGujarat 380009India

Change in land-use practices can result in major shifts in the cycling of various elements,particularly nitrogen(N),which is prone to anthropogenic perturbations.For quantifying these shifts,accurate measurements of rates of biogeochemical transformations of N are needed.We used the(^(15)N) isotope dilution technique to understand the effects of the types of forest alteration on(N) transformation rates by comparing gross N mineralization and ammonium(NH_(4)^(+)) consumption rates in soils of a managed forest,an unmanaged forest,and a rubber plantation in Kerala,India.Overall,nitrate(NO_3~-) dominated soils of the managed and unmanaged forests,whereas soils in the rubber plantation showed relatively higher NH_(4)^(+) concentration.Total N(TN) and total organic carbon(TOC) concentrations were the highest under the rubber canopy(TN:1.49±0.02 mg N g^(-1);TOC:7.96±0.86 mg C g^(-1)).In soils of all three forest types,gross N mineralization rates were higher compared to NH_(4)^(+) consumption rates.Despite high TN and TOC concentrations,the rates of gross N mineralization and NH_(4)^(+) consumption were considerably lower in the rubber plantation(mineralization:1.08±0.08 mg N kg^(-1)d^(-1);consumption:0.85±0.09 mg N kg^(-1) d^(-)) compared to the managed(mineralization:3.71±0.35 mg N kg^(-1) d^(-1);consumption:2.20±1.41 mg N kg^(-1) d^(-1)) and unmanaged(mineralization:2.20±1.07 mg N kg^(-1) d^(-1);consumption:1.39±0.27 mg N kg^(-1) d^(-1)) forests.The lower NH_(4)^(+) consumption rates in the rubber plantation led to significantly higher(p<0.05) residence time of NH_(4)^(+)(~4 days) compared to the managed and unmanaged forests(<2 days),possibly contributing to acidification of rubber soils(pH~4.8).These results together suggest that replacement of naturally grown forests with a mono-cropped plantation such as rubber negatively impact rates of N transformation processes in tropical soils and imply that change in tree species composition of naturally grown forests can adversely affect soil microbial activity.We recommen

关键词： Nitrogen Mineralization Forest soils Rubber plantation Land-use change

Blockchain-Based Secured IPFS-Enable Event Storage Technique With Authentication Protocol in VANET

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IEEE/CAA Journal of Automatica Sinica 2021年第12期8卷 1913-1922页

作者： Sanjeev kumar Dwivedi Ruhul Amin Satyanarayana Vollala Department of CSE Dr.Shyama Prasad Mukherjee International Institute of Information Technology Naya RaipurChhattisgarh 492002India

In recent decades,intelligent transportation systems(ITS)have improved drivers’safety and have shared information(such as traffic congestion and accidents)in a very efficient way.However,the privacy of vehicles and the security of event information is a major concern.The problem of secure sharing of event information without compromising the trusted third party(TTP)and data storage is the main issue in ITS.Blockchain technologies can resolve this problem.A work has been published on blockchain-based protocol for secure sharing of events and authentication of vehicles.This protocol addresses the issue of the safe storing of event information.However,authentication of vehicles solely depends on the cloud server.As a result,their scheme utilizes the notion of partially decentralized architecture.This paper proposes a novel decentralized architecture for the vehicular ad-hoc network(VANET)without the cloud server.This work also presents a protocol for securing event information and vehicle authentication using the blockchain mechanism.In this protocol,the registered user accesses the event information securely from the interplanetary file system(IPFS).We incorporate the IPFS,along with blockchain,to store the information in a fully distributed manner.The proposed protocol is compared with the state-of-the-art.The comparison provides desirable security at a reasonable cost.The evaluation of the proposed smart contract in terms of cost(GAS)is also discussed.

关键词： Authentication blockchain interplanetary file system(IPFS) secure information sharing security