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Segmentation and classification of high spatial resolution images based on Hölder exponents and variance

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Geo-Spatial Information Science 2017年第1期20卷 39-45页

作者： Debasish Chakraborty Sourabh Singh Dibyendu dutta Regional Remote Sensing Centre-East National Remote Sensing CentreISRONew TownKolkataIndia Department of Computer Science and Engineering SMITSikkimIndia

Pixel-based or texture-based classification technique individually does not yield an appropriate result in classifying the high spatial resolution remote sensing imagery since it comprises textured and non-textured *** this study,Hölder exponents(HE)and variance(VAR)are used together to transform the image for measuring texture.A threshold is derived to segment the transformed image into textured and non-textured ***,the original image is extracted into textured and non-textured regions using this segmented image ***,extracted textured region is classified using ISODATA classification algorithm considering HE,VAR,and intensity values of individual pixel of textured *** extracted non-textured region of the image is classified using ISODATA classification *** case of non-textured region,HE and VAR value of individual pixel is not considered for classification for significant textural variation is not found among different ***,the classified outputs of non-textured and textured regions that are generated independently are merged together to get the final classified *** 1 m PAN images are classified using the proposed algorithm,and the classification accuracy is more than 88%.

关键词： High-resolution image texture segmentation Hölder exponents variance contrast classification ISODATA

Gadolinium doped tin dioxide nanoparticles: an efficient visible light active photocatalyst

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Journal of Rare Earths 2015年第12期33卷 1275-1283页

作者： Abdullah M Al-Hamdi Mika Sillanp?? Joydeep dutta Laboratory of Green Chemistry Lappeenranta University of Technology Chair in Nanotechnology Water Research Center Sultan Qaboos University Functional Materials Division School of Information and Communication Technology KTH Royal Institute of Technology

Photocatalytic degradation of phenol with sol-gel prepared rare earth doped tin dioxide （SnO2） nanoparticles was reported. Gadolinium doped tin dioxide （SnO2：Gd） nanoparticles were found to absorb higher visible light compared to lanthanum, neodymium and cerium doped materials that were studied in detail. Photocatalytic degradation of phenol under artificial white light and sunlight in the presence of SnO2：Gd nanoparticles was studied with high performance liquid chromatography （HPLC）, capillary electrophoresis （CE）, total organic carbon （TOC） measurements and the determination of chemical oxygen demand （COD）. Clear correlations be- tween the results obtained from these multiple measurements were found, and a kinetic pathway for the degradation process was pro- posed. Within 150 min of solar irradiation, the TOC of a 10 ppm phenol solution in water was reduced by 95%-99%, thus demon- strating that SnO2：Gd nanoparticles are efficient visible light photocatalysts.

关键词： rare earth dopants solar irradiation phenol photo-degradation tin dioxide nanoparticles organic by-products

Memory response in a nonlocal micropolar double porous thermoelastic medium with variable conductivity under Moore-Gibson-Thompson thermoelasticity theory

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Journal of Ocean Engineering and Science 2023年第3期8卷 263-277页

作者： Shishir Gupta Rachaita dutta Soumik Das Department of Mathematics and Computing Indian Institute of Technology(ISM)DhanbadJharkhand 826004India

The present study enlightens the two-dimensional analysis of the thermo-mechanical response for a mi-cropolar double porous thermoelastic material with voids(MDPTMWV)by virtue of Eringen’s theory of nonlocal ***-Gibson-Thompson(MGT)heat equation is introduced to the considered model in the context of memory-dependent derivative and variable *** employing the normal mode technique,the non-dimensional coupled governing equations of motion are solved to determine the an-alytical expressions of the displacements,temperature,void volume fractions,microrotation vector,force stress tensors,and equilibrated stress *** two-dimensional graphs are presented to demon-strate the influence of various parameters,such as kernel functions,thermal conductivity,and ***,different generalized thermoelasticity theories with variable conductivity are compared to visualize the variations in the distributions associated with the prior mentioned *** particu-lar cases are also discussed in the presence and absence of different parameters.

关键词： Memory-dependent derivative Eringen’s nonlocal elasticity theory Micropolar double porous thermoelastic material with voids Moore-Gibson-Thompson thermoelasicity Variable conductivity

Quality Assessment and Forecast Sensitivity of Global Remote Sensing Observations

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Advances in Atmospheric Sciences 2017年第3期34卷 371-382页

作者： Swapan MALLICK Devajyoti dutta Ki-Hong MIN School of Earth System Sciences Kyungpook National UniversityDaegu 41566South Korea National Centre for Medium Range Weather Forecasting Earth System Science OrganizationNoida 201309India

The satellite-derived wind from cloud and moisture features of geostationary satellites is an important data source for numerical weather prediction （NWP） models. These datasets and global positioning system radio occultation （GPSRO） satellite radiances are assimilated in the four-dimensional variational atmospheric data assimilation system of the UKMO Unified Model in India. This study focuses on the importance of these data in the NWP system and their impact on short-term 24-h forecasts. The quality of the wind observations is compared to the short-range forecast from the model background. The observation increments （observation minus background） are computed as the satellite-derived wind minus the model forecast with a 6-h lead time. The results show the model background has a large easterly wind component compared to satellite observations. The importance of each observation in the analysis is studied using an adjoint-based forecast sensitivity to observation method. The results show that at least around 50% of all types of satellite observations are beneficial. In terms of individual contribution, METEOSAT-7 shows a higher percentage of impact （nearly 50%）, as compared to GEOS, MTSAT-2 and METEOSAT-10, all of which have a less than 25% impact. In addition, the impact of GPSRO, infrared atmospheric sounding interferometer （IASI） and atmospheric infrared sounder （AIRS） data is calculated. The GPSRO observations have beneficial impacts up to 50 km. Over the Southern Hemisphere, the high spectral radiances from IASI and AIRS show a greater impact than over the Northern Hemisphere. The results in this study can be used for further improvements in the use of new and existing satellite observations.

关键词： wind observation increment observation impact forecast sensitivity to observation

Phosphate uptake and translocation in a tropical Canna-based constructed wetland

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Ecological Processes 2017年第1期6卷 122-128页

作者： Anil Kumar Haritash Sarbari dutta Ashish Sharma Department of Environmental Engineering Delhi Technological UniversityBawana RoadShahbad DaulatpurDelhi 110042India

Introduction:Considering the problem of eutrophication of the water bodies,phosphate removal from water has emerged as a research of topical *** present study aims to investigate the efficacy of Canna lily-based constructed wetland to remove phosphate from *** translocation of phosphate in plant tissue and its biochemical transformation in sediments is also studied to understand its accumulation and recirculation within the ***:The removal of phosphate stabilized at around 50%in the present study and plant uptake was found to be the major removal *** removal was 167 mg/m2 day for total phosphate and 84 mg/m2 day for available phosphate for an initial loading rate of 200 mg/m2 day and 85 mg/m2 day,respectively,at a HRT of 24 *** of the phosphate concentrated in above ground tissue of plant and its relative accumulation was maximum in *** of phosphate in sediments confirmed removal by sediments with an accumulation of apatite phosphate(Ca and Mg bound),but release of non-apatite form(Fe and Al bound).Conclusion:The study concludes that Canna-based constructed wetland can be an effective tool for phosphate removal from wastewater and sediments particularly under tropical *** harvesting of above ground tissue of Canna can result in nutrient export from the system,whereas autochthonous addition may result in recirculation.

关键词： Phosphate removal Canna lily Wetland Sediments Wastewater

Remediation of sulfidic wastewater by catalytic oxidation with hydrogen peroxide

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Journal of Environmental Sciences 2009年第12期21卷 1735-1740页

作者： Naveed Ahmad Saikat Maitra Binay Kanti dutta Farooq Ahmad Department of Chemical Engineering Universiti Teknologi PETRONAS Department of Chemical Engineering The Petroleum Institute

Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and ammonia. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-Ray diffraction analysis, scanning electrom microscope and energy dispersive X-ray analysis. The catalyst was quite effective in oxidizing the sulfide by hydrogen peroxide. The effects of sulfide concentration, catalyst loading, H2O2 dosing and temperature on the kinetics of sulfide oxidation were investigated. Kinetic equations and activation energies for the catalytic oxidation reaction were calculated based on the experimental results.

关键词： catalytic oxidation wastewater kinetic equation hydrogen peroxide sodium sulfide remediation

Influence of amphiphilic structures on the stability of polyphenols with different hydrophobicity

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Science China Chemistry 2007年第1期50卷 121-126页

作者： Bergensthl BJrn Food Technology Center for Chemistry and Chemical EngineeringLund UniversityPO Box 124S-22100LundSweden

Autooxidation of five polyphenols representing range of different hydrophobicities(catechin gallate (CG),(-)catechin((-)C),epicatechin(EC),epigallocatechin gallate(EGCG)and epigallocatechin(EGC)) in three different aqueous solutions:molecular solution,micellar solution(Tween-20)and liposomal dispersion(soybean lecithin)was monitored by *** rate of oxidation of the five polyphenols was higher at pH 4.5 than at pH *** with the control,addition of Tween-20(micellar structure)and lecithin(liposomal structure)significantly decreased the degradation of *** the presence of lecithin the autooxidation of all the five polyphenols was slower than in the presence of Tween-20. The effective protection of the colloidal structures was compared with the hydrophobicity of the poly- phenols estimated from the partitioning between octanol and *** protection from oxidation in the presence of the colloidal structures(micellar or liposomal)increased with increasing partitioning of a polyphenol towards the hydrophobic *** protecting effect of the colloidal structures was more effective at pH 4.5 than at pH 3.5.

关键词： amphiphilic structures autooxidation polyphenols K value effective protection

Molecular and cellular pathophysiology of circulating cardiomyocyte-specific cell free DNA (cfDNA): Biomarkers of heart failure and potential therapeutic targets

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Genes & Diseases 2023年第3期10卷 948-959页

作者： Abhi dutta Moumita Das Ankita Ghosh Santanu Rana Raja Peary Mohan College Integrated Biological Research Facility(RIBRF) Raja Peary Mohan CollegeUttarparaHooghlyWest Bengal 712258India

Pathological cardiac damage during heart failure is associated with cell death and damage associated molecular patterns (DAMPs) release which triggers a viscous cycle of sterile inflammation to mediate maladaptive cardiac tissue remodelling during the progression to heart failure. DAMPs like cytokines, chemokines, and nuclear or mitochondrial genomic fragments are released in the pathological myocardium. Interestingly, circulating or cytosolic DNA fragments can play a role in the disease by interaction with nucleic acid sensors expressed in cardiomyocyte and non-myocyte neighbouring cells. The circulating cell free DNA (cfDNA) fragments have been clinically reported as markers for various diseases including cardiovascular pathophysiology. Such cfDNA within the DAMP pool can mediate intra- and inter-cellular signalling cascade to upregulate transcriptional expression of inflammatory mediators and trigger oxidative stress within cells. The cellular role of such genomic equivalents varying with chronic or acute stress might be correlated with the cell death forms encountered in myocardium during disease progression. Thus, cfDNA can be phenotypically correlated as a critical player towards upregulation of pathological processes like interstitial fibrosis, cardiomyocyte contractile dysfunction and cell death. Herein, we review the association of cfDNA with heart failure and analyse their potential usage as novel and effective therapeutic targets towards augmentation of cardiac function.

关键词： Apoptosis Circulating DNA Fibrosis Heart failure Inflammation Nucleic acid receptor

SVM Algorithm for Vibration Fault Diagnosis in Centrifugal Pump

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Intelligent Automation & Soft Computing 2023年第3期35卷 2997-3020页

作者： Nabanita dutta Palanisamy Kaliannan Paramasivam Shanmugam School of Electrical Engineering Vellore Institute of TechnologyVelloreTamilNaduIndia ESAB India Limited ChennaiIndia

Vibration failure in the pumping system is a signiﬁcant issue for indus-tries that rely on the pump as a critical device which requires regular *** save energy and money,a new automated system must be developed that can detect anomalies at an early *** paper presents a case study of a machine learning(ML)-based computational technique for automatic fault detection in a cascade pumping system based on variable frequency drive(VFD).Since the intensity of the vibrational effect depends on which axis has the most signiﬁcant effect,a three-axis accelerometer is used to measure it in the pumping *** emphasis is on determining the vibration effect on different *** experiment,various ML algorithms are investigated on collected vibratory data through Matlab software in x,y,z axes and performances of the algorithms are compared based on accuracy rate,prediction speed and training *** on the proposed research results,the multiclass support vector machine(MSVM)is found to be the best suitable algorithm compared to other *** has been demonstrated that ML algorithms can detect faults automatically rather than conventional *** is used for the proposed work because it is less complex and pro-duces better results with a limited data set.

关键词： Fault diagnosis machine learning pump vibration analysis variable frequency drive