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A Local Contrast Fusion Based 3D Otsu Algorithm for Multilevel Image Segmentation

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 200-213页

作者： Ashish kumar Bhandari Arunangshu ghosh Immadisetty Vinod kumar Department of Electronics and Communication Engineering National Institute of Technology Patna

To overcome the shortcomings of 1 D and 2 D Otsu’s thresholding techniques, the 3 D Otsu method has been *** all Otsu’s methods, 3 D Otsu technique provides the best threshold values for the multi-level thresholding processes. In this paper, to improve the quality of segmented images, a simple and effective multilevel thresholding method is introduced. The proposed approach focuses on preserving edge detail by computing the 3 D Otsu along the fusion phenomena. The advantages of the presented scheme include higher quality outcomes, better preservation of tiny details and boundaries and reduced execution time with rising threshold levels. The fusion approach depends upon the differences between pixel intensity values within a small local space of an image;it aims to improve localized information after the thresholding process. The fusion of images based on local contrast can improve image segmentation performance by minimizing the loss of local contrast, loss of details and gray-level distributions. Results show that the proposed method yields more promising segmentation results when compared to conventional1 D Otsu, 2 D Otsu and 3 D Otsu methods, as evident from the objective and subjective evaluations.

关键词： 1D Otsu 2D Otsu 3D Otsu image fusion local contrast multi-level image segmentation

Fluid Inclusion Characteristics of Tungsten Mineralization in the Agargaon Area of Sakoli Fold Belt, Central India

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Journal of Earth Science 2020年第3期31卷 559-570页

作者： Girish kumar Mayachar Subhasish ghosh National Centre for Excellence in Geoscience Research Remote Sensing and Aerial SurveyGeological Survey of IndiaBangalore 560078India

The Lower to Middle Proterozoic Sakoli fold belt in Central India forms a triangular belt with significant mineralization of strategic *** Sakoli fold belt comprises metasediments,felsic and mafic volcanics with metabasalts bounded by the gneissic-migmatitic *** last pulses of granitic activity in the form of quartz lenses intrude the metasediments and are associated with tungsten *** metasediments are intruded by the quartz veins and tourmaline breccias trending 60°N to 65°E and 60°S to 65°W and are parallel to the regional structural *** tungsten mineralization in this area is restricted to tourmaline-quartz mica greisens and quartz *** NE-SW trending foliated contact zones of chlorite mica schist and porphyritic granite/gneisses have served as easy channels for the mineralizing vapours and solutions to percolate,which formed ore bearing greisens and quartz *** mineralization is erratic and manifested by sparse and sporadic disseminations of wolframite and scheelite associated with minor amount of molybdenite and *** fluid inclusion microthermometry on mineralized quartz veins and quartz-tourmaline veins reveals the existence of a metamorphogenic aqueous-gaseous(H2O-CO2+NaCl)fluid that underwent phase separation and gave rise to gaseous(CO2)*** salinity of tungsten mineralizations varies from low to high(1.32 wt.%to 40.44 wt.%NaCl eq.).The estimated P-T range of tungsten mineralization varies from 1.2 to 2.2 kbar at 280 to 390℃.Raman spectroscopy reveals that the fluid inclusions mainly contain H2O and CO2 with rarely H2S and *** isotopic data reveal that the sulfur isotope fractions from the depositsδ^34S ranging from+3.1‰to+3.35‰,suggesting the deep crustal source for the sulfur,which can be further interpreted as a single(magmatic)supply of sulfur during magmatic-hydrothermal *** studies reveal the presence of chlorides such as FeCl2/MgCl2 and CaCl2,indicating t

关键词： Sakoli fold belt fluid inclusions tungsten

COVID-19's impacts on dengue transmission:Focus on neighbourhood surveillance of Aedes mosquitoes

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Asian Pacific Journal of Tropical Medicine 2022年第8期15卷 339-340页

作者： Susanta kumar ghosh Chaitali ghosh ICMR-National Institute of Malaria Research BangaloreIndia Tata Institute for Genetics and Society BangaloreIndia

The ongoing COVID-19 pandemic has impacted the entire globe on all fronts,and vector-borne diseases are not an *** are certain similarities between dengue and COVID-19 since both diseases are positive-sense single-stranded RNA virus and have animal origin ***,both the diseases present over 80%asymptomatic *** is the most prevalent and fast-emerging viral infection *** dengue virus(DENV)has four serotypes,namely DENV-1,DENV-2,DENV-3 and DENV-4,and it is possible that the same person can be infected four times before full immunity is established[1];whereas,COVID-19 is an air-borne respiratory disease caused by the severe acute respiratory syndrome coronavirus 2,and several variants have emerged over *** late 2020,the variants posed an increased risk to global public health emergency,which prompted the characterisation of specific Variants of Interest and Variants of Concern to mitigate the COVID-19 pandemic[2].DENV is transmitted by several species of day-biting Aedes *** are highly adaptive and invasive species and are predominantly found in the tropical and subtropical *** recent decades,these mosquitoes have been discovered in all continents except *** aegypti and Aedes albopictus are two major vectors of *** means wherever these mosquitoes make their footprints,dengue creeps in.

关键词： immunity Focus prompt

Finite-time tracking control of heterogeneous multi-AUV systems with partial measurements and intermittent communication

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Science China(Information Sciences) 2024年第5期67卷 165-182页

作者： Bo CHEN Jiangping HU Bijoy kumar ghosh School of Automation Engineering University of Electronic Science and Technology of China Key Laboratory of Intelligent Analysis and Decision on Complex Systems Chongqing University of Posts and Telecommunications Yangtze Delta Region Institute (Huzhou) University of Electronic Science and Technology of China Department of Mathematics and Statistics Texas Tech University

The development of a distributed trajectory-tracking control strategy that is independent of velocity measurements is critical to achieving finite-time tracking control of autonomous underwater vehicle(AUV) systems. In this study, a group of heterogeneous AUV systems with intermittent communication links is considered and a finite-time trajectory-tracking control strategy is developed. The strategy includes two observers and one controller proposed for each follower-AUV. The first observer, a hybrid finite-time observer,estimates the state of the leader, whereas the second observer, which relies only on the position measurement,is proposed to estimate the states of the follower-AUV itself. In addition, a distributed trajectory-tracking controller is designed using the states estimated by the intermittent communication network even without velocity measurements. A homogeneous technique is utilized to prove that all followers can track the leader in a finite time. Finally, the effectiveness of the developed finite-time tracking control strategy is illustrated by numerical simulations.

关键词： distributed observer finite-time tracking homogeneous technique intermittent communication multiple heterogeneous AUVs

Wear and performance analysis of a 4-stroke diesel engine employing nanolubricants

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Particuology 2018年第2期16卷 54-63页

作者： Ankit Kotia Sheeba Borkakoti Subrata kumar ghosh Department of Mechanical Engineering DIT University Dehradun India Department of Mechanical Engineering Indian Institute of Technology (Indian School of Mines) Dhanbad India

In the present study, the performance of a 4-stroke diesel engine was experimentally evaluated upon adding Al2O3 or SiO2 nanoparticles to the engine oil （SAEISW40）. The viscosity and density of the resulting nanolubricants were determined while varying both the nanoparticle volume fraction and the temperature. Field emission scanning electron microscopy （FE-SEM） showed that the nanoparticles had a spherical morphology and dynamic light scattering analysis determined some aggregation of the nanoparticles in the engine oil. A pin-on-disc test apparatus was used for friction and wear analysis in the presence of the nanolubricants. Examination of wear scars by FE-SEM and energy dispersive spectroscopy found evidence of ball bearing and surface polishing effects, which were responsible for improvements in the tribological properties of the oil. The performance of these nanolubricants in a 4- stroke diesel engine test rig was assessed, and the greatest improvements in the tribological behavior and engine performance were observed when employing 0.3 vol% Al2O3.

关键词： SiO2 Al2O3 Engine oil 4-Stroke diesel engine Wear Friction

Mathematical Study of A Memory Induced Biochemical System

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IEEE/CAA Journal of Automatica Sinica 2018年第6期5卷 1142-1149页

作者： Mithun kumar ghosh Tridip Sardar Xianbing Cao Priti kumar Roy Centre for Mathematical Biology and Ecology Department of MathematicsJadavpur University Department of Mathematics Dinabondhu Andrews College College of Science Beijing Technology and Business University

In this work, to study the effect of memory on a bi-substrate enzyme kinetic reaction, we have introduced an approach to fractionalize the system, considering it as a threecompartmental model. Solutions of the fractionalized system are compared with the corresponding integer-order model. The equilibrium points of the fractionalized system are derived analytically. Their stability properties are discussed from numerical aspect. We determine the changes of the substances due to the changes of "memory effect". The effect is discussed critically from the perspective of product formation. We have also analyzed the memory induced system with a control measure in view of optimizing the product. Our numerical result reveals that the solutions of the fractionalized system, when it is free from memory, are in good agreement with the integer-order *** is noticed that the effect of memory influences the reaction in the forward direction and assists in yielding the product more quickly. However, an extensive use of memory makes the system slower, but introduction of a control input makes the reaction faster. It is possible to overcome the slowness of the reaction due to the undue effect of memory by appropriate use of a control measure.

关键词： Bi-substrate enzymatic reaction compartmental system control theoretic approach fractional-order differential equations memory effect

Performance Evaluation of Modified Black Clay as a Heterogeneous Fenton Catalyst on Decolorization of Azure B Dye: Kinetic Study and Cost Evaluation

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Transactions of Tianjin University 2019年第5期25卷 527-539页

作者： Vijyendra kumar Prabir ghosh Department of Chemical Engineering National Institute of Technology(India)

Black clay (BC) was used as a catalyst for the decolorization of Azure B dye by Fenton process. BC was modi ed by acid, alkali, distilled water, and calcination to check their changes in characterization and e ciency on decolorization of Azure B. Among three modi ed catalysts, maximum decolorization was obtained by acid-modi ed BC (AMBC) catalyst due to the highest removal of impurities, comparatively. The characterization of AMBC was done by Fourier-transform infrared spectroscopy and X-ray di raction spectroscopy which show the presence of metal ion. The BET surface area, pore volume, pore size, and density of AMBC were calculated to be 79.402 m 2 /g, 0.0608 m 3 /g, 0.00306 nm, and 16 g/cm 3 , respectively. The highest decolorization of 97.59% was achieved only in 10 min using AMBC at optimized calcination of 100 °C and 3 h of aging. AMBC was considered as the main catalyst for optimizing the di erent process parameters. Optimized conditions were obtained: pH 2, 0.2 mL of H 2 O 2 , catalyst dose 0.3 g, room temperature (30 °C), and stirring speed 400 r/min. The catalyst has showed excellent stability and reusability. It could remove more than 85% of color even after four cycles of run and less than negligible leaching of iron. AMBC has good recycling ability among other modi ed catalysts. To check the selectivity of catalyst, di erent dyes such as Congo red and mixed dye (mixture of Azure B and Congo red) decolorization were studied. In the present work, kinetic study was also carried out and a three-stage decolorization process was found.

关键词： Black clay Azure B Heterogeneous Fenton process Wastewater treatment

Adder design using a 5-input majority gate in a novel “multilayer gate design paradigm” for quantum dot cellular automata circuits

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Journal of Semiconductors 2015年第4期36卷 95-103页

作者： Rohit kumar Bahniman ghosh Shoubhik Gupta Department of Electrical Engineering Indian Institute of Technology Kanpur Microelectronics Research Center 10100Burnet RoadBldg. 160University of Texas at Austin University of Glasgow

This paper proposes a novel design paradigm for circuits designed in quantum dot cellular automata （QCA） technology. Previously reported QCA circuits in the literature have generally been designed in a single layer which is the main logical block in which the inverter and majority gate are on the base layer, except for the parts where multilayer wire crossing was used. In this paper the concept of multilayer wire crossing has been extended to design logic gates in multilayers. Using a 5-input majority gate in a multilayer, a 1-bit and 2-bit adder have been designed in the proposed multilayer gate design paradigm. A comparison has been made with some adders reported previously in the literature and it has been shown that circuits designed in the proposed design paradigm are much more efficient in terms of area, the requirement of QCA cells in the design and the input-output delay of the circuit. Over all, the availability of one additional spatial dimension makes the design process much more flexible and there is scope for the customizability of logic gate designs to make the circuit compact.

关键词： multilayer gate design QCA adders MUX 5-input majority voter

A Comparative Assessment of Temperature Data from Different Sources for Dehradun, Uttarakhand, India

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Journal of Meteorological Research 2016年第6期30卷 1019-1032页

作者： Atul Kant PIYOOSH Sanjay kumar ghosh Department of Civil Engineering Indian Institute of Technology Roorkee

A comparative study of extreme temperature parameters from different sources is carried out by examining standardized anomalies, trends, correlation, and equivalence of datasets. Maximum temperature （Tmax） and minimum temperature （Wmln） for Dehradun, from two different sources such as computed and gridded data from Climatic Research Unit （CRU） and observed data from India Meteorological Department （IMD） are used for 1901-2012. The CRU data are compared initially with IMD, by graphical assessment of standardized anomalies. Subsequently, change points are identified by using Cumulative Sum （CUSUM）-chart technique for trend analysis. The magnitude and significance of trends are determined by applying Sen＇s slope test, and on the basis of these, trends are compared. Further, correlation analysis is carried out and datasets are tested for equivalence by using Wileoxon-Mann Whitney test. The result shows that annual standardized anomalies of CRU data follow the pattern of annual standardized anomalies of IMD data. The CRU data exhibit similar trends and are well correlated with IMD dataset. Moreover, CRU anomaly data are identical with IMD anomaly data in the recent decades. High resolution gridded CRU data have open access and may be more useful due to its spatio-temporal continuity for land areas of the world.

关键词： cumulative sum Sen's slope temperature trend temperature anomaly correlation Wilcoxon Mann-Whitney test