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Modeling, analysis, and optimization of dimensional accuracy of FDM-fabricated parts using definitive screening design and deep learning feedforward artificial neural network

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Advances in Manufacturing 2021年第1期9卷 115-129页

作者： Omar Ahmed Mohamed Syed Hasan Masood Jahar Lal bhowmik School of Engineering Deakin UniversityGeelongAustralia Department of Mechanical Engineering Higher Institute of Engineering TechnologyBani WalidLibya Department of Mechanical and Product Design Engineering Swinburne University of TechnologyHawthornVIC 3122Australia Department of Health Science and Biostatistics Swinburne University of TechnologyHawthornVIC 3122Australia

Additive manufacturing(AM)technologies such as fused deposition modeling(FDM)rely on the quality of manufactured products and the process ***,the dimensional accuracy and stability of any AM process is essential for ensuring that customer specifications are satisfied at the highest standard,and variations are controlled without significantly affecting the functioning of processes,machines,and product *** study aims to investigate the effects of FDM fabrication conditions on the dimensional accuracy of cylindrical *** this study,a new class of experimental design techniques for integrated second-order definitive screening design(DSD)and an artificial neural network(ANN)are proposed for designing experiments to evaluate and predict the effects of six important operating *** determining the optimum fabrication conditions to obtain better dimensional accuracies for cylindrical parts,the time consumption and number of complex experiments are reduced considerably in this *** optimum fabrication conditions generated through a second-order DSD are verified with experimental *** results indicate that the slice thickness,part print direction,and number of perimeters significantly affect the percentage of length difference,whereas the percentage of diameter difference is significantly affected by the raster-to-raster air gap,bead width,number of perimeters,and part print ***,the results demonstrate that a second-order DSD integrated with an ANN is a more attractive and promising methodology for AM applications.

关键词： Artificial neural network(ANN) OptimizationDefinitive screening design(DSD) Analysis of variance(ANOVA) Fused deposition modeling(FDM) Dimensional accuracy

A hybrid model for energy efficient spectrum sensing in cognitive radio

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International Journal of Intelligent Computing and Cybernetics 2022年第2期15卷 165-183页

作者： Mahua bhowmik P.Malathi PES’s Modern College of Engineering SPPUPuneIndia D.Y.Patil College of Engineering PuneIndia

Purpose-Cognitive radio(CR)plays a very important role in enabling spectral efficiency in wireless communication networks,where the secondary user(SU)allows the licensed primary users(PUs).The purpose of this paper is to develop a prediction model for spectrum sensing in ***/methodology/approach-This paper proposes a hybrid prediction model,called krill-herd whale optimization-based actor critic neural network and hidden Markov model(KHWO-ACNN-HMM).The spectral bands are determined optimally using the proposed hybrid prediction model for allocating the spectrum bands to the *** better sensing,the eigenvalue based on cooperative sensing used in ***,a hybrid model is designed by hybridizing KHWO-ACNN and HMM to enhance the accuracy of *** predicted results of KHWO-ACNN and HMM are combined by a fusion model,for which a weighted entropy fusion is employed to determine the free spectrum available in ***-The performance of the prediction model is evaluated based on metrics,such as probability of detection,probability of false alarm,throughput and sensing *** proposed spectrum sensing method achieves maximum probability of detection of 0.9696,minimum probability of false alarm rate as 0.78,minimum throughput of 0.0303 and the maximum sensing time of 650.08 *** implications-The proposed method is useful in various applications,including authentication applications,wireless medical networks and so ***/value-A hybrid prediction model is introduced for energy efficient spectrum sensing in CR and the performance of the proposed model is evaluated with the existing *** proposed hybrid model outperformed the other techniques.

关键词： Actor critic neural network Cognitive radio Spectrum sensing Optimization Hidden Markov Model

Load shedding strategy coordinated with storage device and D-STATCOM to enhance the microgrid stability

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Protection and Control of Modern Power Systems 2019年第1期4卷 262-280页

作者： Sheetal Chandak Pritam bhowmik Pravat Kumar Rout Electrical Engineering Department Siksha‘O’Anusandhan UniversityBhubaneswar751030India Electrical and Electronics Engineering Department Siksha‘O’Anusandhan UniversityBhubaneswar751030India

Recently microgrids have drawn a potential attraction by fulfilling the environmental demands and the increasing energy demands of the end-users. It is necessary to focus on various protection and control aspects of a microgrid. During the transition between the grid-following and grid-forming modes, the voltage and the frequency instability due to the power mismatch condition becomes the major point of concern. Therefore, the paper executes a frequency-active power and voltage-reactive power drooping control strategy for the precise power-sharing among the distributed power generators. Furthermore, to handle the power deficit scenarios and to maintain the system stability, a system independent and priority-based adaptive three-stage load shedding strategy is proposed. The sensitivity of the strategy depends on the system inertia and is computed according to the varying absolute rate-of-change-of-frequency. The strategy incorporates the operation of battery storage system and distributed static compensator (D-STATCOM) in the microgrid, to provide a reliable power supply to the customers for a considerable time instead of a sudden load shedding. The effectiveness of the proposed strategies is investigated on a scaled-down modified IEEE 13-bus microgrid system on the podium of MATLAB 2015b through the time-domain simulation.

关键词： Microgrid Power-sharing Load shedding High inertia distributed generators Inertia-less distributed generators Battery storage system D-STATCOM

Reliability and efficiency enhancement of a radial distribution system through value-based auto-recloser placement and network remodelling

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Protection and Control of Modern Power Systems 2023年第1期8卷 1-14页

作者： Bratati Ghosh Ajoy Kumar Chakraborty Arup Ratan bhowmik Department of Electrical Engineering National Institute of Technology AgartalaJiraniaTripura 799046India

The electric distribution system(EDS)is prone to faults leading to power *** present energy market demands that electricity utilities invest more in different measures to improve the performance of the *** approach proposed here details a composite dual-phased methodology to improve the reliability and efficiency of the power delivered by the *** the first phase,the optimal allocation of auto-reclosers(AR)is undertaken by employing a newly formulated *** determination of the total number and location for AR placement is based on the economic analysis of two factors,i.e.,AR investment-maintenance cost and total benefit earned in terms of reliability improvement due to AR *** analysis also takes into account the impact of power outages on different load types,the load growth rate,and the inflation ***,to enhance the efficiency of the AR-incorpo-rated EDS,the technique of Radial Distribution System Remodelling is employed in the second *** method searches for a radial configuration that delivers power at minimum line *** phases comprising complex combinatorial operations are aided by a fresh hybrid of the Sine Cosine Algorithm,Krill Herd Algorithm,and a genetic operator of Differential *** results obtained from its application on the IEEE 69-bus distribution test system prove the credibility of the suggested formulation.

关键词： Auto-recloser placement Load flow Metaheuristic optimization algorithm Power loss minimization Reconfiguration Reliability assessment

Thermal history of a Late Mesoproterozoic paired metamorphic belt(?)during Rodinia assembly:New insight from medium-pressure granulites from the Aravalli-Delhi Mobile Belt, Northwestern India

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Geoscience Frontiers 2018年第2期9卷 335-354页

作者： Santanu Kumar bhowmik Somnath Dasgupta Sudipta Baruah Deepika Kalita Department of Geology and Geophysics Indian Institute of Technology Kharagpur Department of Geography Faculty of Natural SciencesJamia Millia Islamia

In this study, we investigate the possible record of a Late Mesoproterozoic paired metamorphic belt in the Aravalli-Delhi Mobile Belt(ADMB), NW India using a suite of supracrustal and metaigneous granulites from the Pilwa-Chinwali granulite terrain at the north-western margin of the ADMB. Using metamorphic reaction textures, mineral chemistry, metamorphic reaction history, geothermobarometric computations and electron microprobe dating of monazite in 5 samples of pelitic granulite, leptynite gneiss, enderbite and charnockite, we have deduced a medium-pressure granulite facies metamorphism(P between 4.9 and 6.8 kbar, T> 760-815℃) along a heating-cooling, counterclockwise P-T path between 1.09 and 1.01 Ga. When collated with published metamorphic and chronological constraints and geological settings of the adjoining crustal domains of the ADMB, these findings provide new insights into the developments of two tectonic domains of contrasting thermal gradients at ca. 1.0 Ga, consistent with metamorphic transformations in tectonically thickened middle-lower crustal sections during continental collision to continental subduction and in the root zones of spatially adjacent island arc, as part of the Rodinia supercontinent assembly event.

关键词： ADMB Granulites CCW-P-T path Monazite chemical dating ca. 1.0 Ga metamorphism Paired metamorphic belt

A Highly Accurate Dysphonia Detection System Using Linear Discriminant Analysis

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Computer Systems Science & Engineering 2023年第3期44卷 1921-1938页

作者： Anas Basalamah Mahedi Hasan Shovan bhowmik Shaikh Akib Shahriyar Department of Computer Engineering Umm Al-Qura UniversityMakkahSaudi Arabia Department of Computer Science and Engineering Khulna University of Engineering&TechnologyKhulna9203Bangladesh

The recognition of pathological voice is considered a difficult task for speech ***,otolaryngologists needed to rely on oral communication with patients to discover traces of voice pathologies like dysphonia that are caused by voice alteration of vocal folds and their accuracy is between 60%–70%.To enhance detection accuracy and reduce processing speed of dysphonia detection,a novel approach is proposed in this *** have leveraged Linear Discriminant Analysis(LDA)to train multiple Machine Learning(ML)models for dysphonia *** ML models are utilized like Support Vector Machine(SVM),Logistic Regression,and K-nearest neighbor(K-NN)to predict the voice pathologies based on features like Mel-Frequency Cepstral Coefficients(MFCC),Fundamental Frequency(F0),Shimmer(%),Jitter(%),and Harmonic to Noise Ratio(HNR).The experiments were performed using Saarbrucken Voice Data-base(SVD)and a privately collected *** K-fold cross-validation approach was incorporated to increase the robustness and stability of the ML *** to the experimental results,our proposed approach has a 70%increase in processing speed over Principal Component Analysis(PCA)and performs remarkably well with a recognition accuracy of 95.24%on the SVD dataset surpassing the previous best accuracy of 82.37%.In the case of the private dataset,our proposed method achieved an accuracy rate of 93.37%.It can be an effective non-invasive method to detect dysphonia.

关键词： Dimensionality reduction dysphonia detection linear discriminant analysis logistic regression speech feature extraction support vector machine

Development and Characterization of Al_2O_3 Dispersed Al/Mg/Cu/Ti Matrix Composite

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Journal of Materials Science & Technology 2013年第11期29卷 1085-1090页

作者： Sumit Chabri Subhranshu Chatterjee Santanu Pattanayak Himel Chakraborty Nandagopal bhowmik Arijit Sinha Department of Metallurgy and Materials Engineering Bengal Engineering and Science University School of Materials Science and Engineering Bengal Engineering and Science University

The effect of dispersion with different weight fractions of Al2O3 particles in metallic matrices （AI/Mg/Ti/Cu） fabricated by powder metallurgy was investigated. In the case of 15 wt% Al2O3 reinforced composites, peak hardness was attained which subsequently decreased with increasing the content of Al2O3. A correlation between the microhardness and nanomechanical properties at submicron scale was examined for all the composites. Specific strength and specific modulus were measured in order to figure out the performance of the composites.

关键词： Metal matrix composites Powder metallurgy Hardening Coarsening Hardness Nanoindentation

Correlation between human gut microbiome and diseases

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Infectious Medicine 2022年第3期1卷 180-191页

作者： Barkha Madhogaria Priyanka bhowmik Atreyee Kundu Department of Microbiology Techno India UniversityWest Bengal EM-4 Sector-VSalt Lake CityKolkata 700091West BengalIndia Department of Biological Sciences Adamas UniversityBarrackpore-Barasat Road24 Paragnas NorthJagannathpurKolkataWest BengalIndia

Human gut microbiome is a major source of human bacterial population and a significant contribution to both positive and harmful *** to its involvement in a variety of interactions,gut microorganisms have a great impact on our health throughout our *** impact of gut microbial population is been studied intensively in last two *** literature survey focusing developments in the field were searched in English language Electronic Databases like PubMed,Google Scholar,Pubag,Google books,and Research Gate were mostly used to understand the role of human gut mirobiome and its role in different human *** microbiome in healthy subjects differs from those who suffer from *** 2 diabetes,obesity,non-alcoholic liver disease,and cardiometabolic diseases have all been linked to dysbiosis of the gut *** of many disorders is also linked to changes in gut *** diseases like cancer,arithritis,autism,depression,anxiety,sleep disorder,HIV,hypertension,and gout are also related to gut microbiota *** focus in this review on recent studies looking into the link between gut microbiome dysbiosis and disease *** on how gut microbiota affects host metabolism has been changed in past decades from descriptive analyses to high throughput integrative omics data analysis such as metagenomics and *** of molecular mechanisms behind reported associations is been carried out in human,animals,and cells for measure of host physiology and *** many the mechanisms are not completely understood.

关键词： Bacteria Gut Infections Microbiome Microbiota Microflora

Optimization of fused deposition modeling process parameters:a review of current research and future prospects

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Advances in Manufacturing 2015年第1期3卷 42-53页

作者： Omar A.Mohamed Syed H.Masood Jahar L.bhowmik Department of Mechanical and Product Design Engineering Faculty of ScienceEngineering and TechnologySwinburne University of TechnologyHawthornMelbourneAustralia Department of Psychological Sciences and Statistics Faculty of HealthArts and DesignSwinburne University of TechnologyHawthornMelbourneAustralia

Fused deposition modeling （FDM） is one of the most popuIar additive manufacturing technologies for various engineering applications. FDM process has been introduced commercially in early 1990s by Stratasys Inc., USA. The quality of FDM processed parts mainly depends on careful selection of process variables. Thus, identifica- tion of the FDM process parameters that significantly affect the quality of FDM processed parts is important. In recent years, researchers have explored a number of ways to improve the mechanical properties and part quality using various experimental design techniques and concepts. This article aims to review the research carried out so far in determining and optimizing the process parameters of the FDM process. Several statistical designs of experiments and optimization techniques used for the determination of optimum process parameters have been examined. The trends for future FDM research in this area are described.

关键词： Fused deposition modeling (FDM) -Experimental design. Additive manufacturing. Processparameters. Mechanical properties.Part quality