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Defence Technology（防务技术） 2019年第3期15卷 326-337页

作者： Swagatam Paul Partha Dey Snehasish Bhattacharjee Sanjib Kumar Acharyya Prasanta Sahoo jayanta chattopadhyay Department of Mechanical Engineering Jadavpur University Kolkata India Department of Mechanical Engineering Academy of Technology Hooghly West Bengal India Bhaba Atomic Research Centre Mumbai India

In the present study a phenomenological constitutive model is developed to describe the flow behaviour of 20MnMoNi55 low carbon reactor pressure vessel (RPV) steel at sub-zero temperature under different strain rates. A set of uniaxial tensile tests is done with the variation of strain rates and temperature ranging from 10^-4s^-1 to 10^-1s^-1 and -80℃ to 140℃ respectively. From the experimental data, family of flow curves at different temperatures and strain rates are generated and fitted exponentially. The strain rate and temperature dependence of the coefficients of the exponential flow curves are extracted from these curves and characterised through a general phenomenological constitutive coupled equation. The coefficients of this coupled equation are optimised using genetic algorithm. Finite element simulation of tensile tests at different strain rates and temperatures are done using this coupled equation in material model of Abaqus FEA software and validated with experimental results. The novelties of proposed model are:(a) it can predict precisely the flow behaviour of tensile tests (b) it is a simple form of equation where fitting parameters are both function of strain rate ratio and temperature ratio,(c) it has ability to characterize flow behaviour with decreasing subzero temperatures and increasing strain rates.

关键词： Flow behaviour RPV steel Cryogenic temperature Strain rate

Nil Clean Graphs of Rings

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Algebra Colloquium 2017年第3期24卷 481-492页

作者： Dhiren Kumar Basnet jayanta Bhattacharyya Department of Mathematical Sciences Tezpur University Napaazn Tezpur-784028 Assam India

In this article, we define the nil clean graph of a ring R. The vertex set is the ring R, and two ring elements a and b are adjacent if and only if a ＋ b is nil clean in R. Graph theoretic properties like the girth, ... 详细信息

关键词： nil clean ring weak nil clean ring nil clean graph

Geochemical characteristics of Neogene sandstones of the East and West Siang Districts of Arunachal Pradesh,NE India:implications for source-area weathering,provenance,and tectonic setting

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Acta Geochimica 2022年第1期41卷 100-120页

作者： Roshmi Boruah jayanta Jivan Laskar Department of Geological Sciences Gauhati UniversityGuwahatiAssam 781014India

Sandstones from the Neogene Siwalik successions of the East and West Siang Districts of Arunachal Pradesh were analyzed to evaluate source-area weathering,provenance,and tectonic setting by using major,trace,and rare earth elements(REEs)as *** sandstones are classified as lithic arenite and wacke arenite based on their mineralogical *** values of different weathering indices such as Chemical Index of Alteration(CIA;60.93–89.86)and Chemical Index of Weathering(CIW;40–96.8)suggest moderate to intense weathering in the source *** plot of Th/Sc versus Zr/Sc indicates enrichment of zircon by sediment sorting and/or recycling from a weathered *** high positive correlation between Al2 O_(3) and K2 O points towards a strong influence of the constituent clay minerals on the major oxide composition of the *** analysis together with enriched LREE,flat HREE,negative Eu anomalies(Eu/Eu^(*)=0.47 to 0.90)in the chondrite-normalized diagrams,and the ratios of La/Sc,La/Co,Th/Sc,Th/Co,Cr/Th collectively suggests that the Neogene sediments were derived from felsic igneous and/or reworked sedimentary/metasedimentary sources in an upper continental crustal *** geochemical characteristics of the studied Neogene Siwalik sandstones indicate that the sediments were sourced from pre-Himalayan gneisses and granitoids together with metabasic rocks,which had formed in a passive margin tectonic setup.

关键词： Geochemistry Neogene sandstones Arunachal Pradesh Paleo-weathering Provenance Tectonic setting

Soft-sediment deformation structures in the Mesoproterozoic Kaimur Sandstone,Vindhyan Supergroup(Central India),and their seismotectonic implications

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Journal of Palaeogeography 2023年第3期12卷 463-486页

作者： jayanta Kumar Pati Anuj Kumar Singh Department of Earth and Planetary Sciences Faculty of ScienceUniversity of AllahabadPrayagraj211002India National Centre of Experimental Mineralogy and Petrology 14 Chatham LinesUniversity of AllahabadPrayagraj211002India

The unequivocal identification of soft-sediment deformation structures(SSDS)is a significant attribute to constrain the effect of transient geological events in the spatio-temporal evolution of ancient sedimentary *** paper reports and discusses,for the first time,the occurrence of several cm-to dm-scale SSDS within sandstone successions of the Mesoproterozoic Kaimur Group(Vindhyan Supergroup),exposed at the Hanumandhara Hill of Chitrakoot-Satna border region,Madhya Pradesh State,*** SSDS are confined to a deformed interval comprising seven individual sedimentary units of variable composition and texture,which are sandwiched between nearly horizontally undeformed sandstone *** SSDS consist of load structures(load casts,flame structures,pseudonodules and ball-and-pillow structures),contorted lamination,convolute lamination,boudins and pinch-and-swell structures,deformed cross-stratification,slump structures,clastic injections,fluid escape structures,and syn-sedimentary fractures/*** pre-sent study suggests that the formation of these SSDS is essentially related to a combination of processes(gravitational instability,liquefaction,fluidization,and fluid escape)predominantly induced by seismic *** addition,the restricted occurrence of fractures/faults in these deformed layers emphasizes the passage of seismically-induced Rayleigh *** the observed types of SSDS,their lateral homo-geneity and geographic distribution along with the geodynamic framework of the Vindhyan Basin,the whole area can be tentatively attributed to having experienced moderate-to high-magnitude(M≥5)*** present study combined with earlier reports of seismically-induced SSDS,from other regionally disposed formations belonging to the Lower(e.g.,Kajrahat Limestone,Chopan Porcellanite,Koldaha Shale,Rohtas Limestone,and Glauconitic Sandstone of the Semri Group)and Upper(e.g.,Bhander Limestone of the Bhander Group)Vindhyan Supergroup,respectively,provi

关键词： Soft-sediment deformation structures SSDS Seismites Kaimur Group Vindhyan Basin Sand-stone Central India

Metallogeny of the Lannigou Sedimentary Rock-hosted Disseminated Gold Deposit in Southwestern Guizhou Province,China

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Acta Geologica Sinica(English Edition) 2007年第1期81卷 121-134页

作者： BAO Zhiwei jayanta GUHA Key Laboratory for MetaUogenic Dynamics Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou Guangdong 510640 China Earth Sciences/CERM University of Quebec at Chicoutimi Chicoutimi P.Q. G7H 2B1 Canada

The Lannigou deposit is a large-sized sedimentary rock-hosted disseminated gold （SRHDG） deposit located in the Youjiang Basin. It is hosted by the Middle Triassic turbidite. Wall rock alterations, including silicification, pyritization, arsenopyritization, carbonatization and argillization, commonly occur along fractures. PGE study demonstrates that either Permian basalts or Triassic ultrabasic intrnsives are unlikely to be the main source of gold mineralization. Coupled with the lack of other nmgmatic activity in the vicinity of the mining area, an amagmatic origin is proposed. Organic matter compositions and GC-MS analysis of the ores and host rocks show that the organics in the ores and the host rocks have a common source; the organic matter in the ores was mainly indigenous. The positive correlation between S2 and Au contents, along with the common occurrence of organic inclusions, suggest involvement of organic matter in the ore-forming process in terms of promoting Au leaching from the source rocks, making colloidal Au migration possible, as well as hydrocarbon reduction of sulphate. Geological and geochemical characteristics of the Lannigou deposit suggest that it was formed through circulation of meteoric water and probably less importantly organic bearing formation water driven by high geothermal gradient caused by late Yanshanian extension, which leached Au from the source bed, and then migrated as Au-bisnlfides and colloidal Au, culminating in deposition by reduction-adsorption and surface complexation of gold onto the growth surface of arsenlan pyrite.

关键词： sedimentary rock-hosted disseminated gold deposit metallogeny Lannigou Guizhou

Design and performance evaluation of a parking management system for automated, multi-story and robotic parking structure

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International Journal of Intelligent Computing and Cybernetics 2019年第4期12卷 444-465页

作者： Gursel Serpen jayanta Debnath The University of Toledo ToledoOhioUSA

Purpose–The purpose of this paper is to present design and performance evaluation through simulation of a parking management system(PMS)for a fully automated,multi-story,puzzle-type and robotic parking structure with the overall objective of minimizing customer wait times while maximizing the space ***/methodology/approach–The presentation entails development and integration of a complete suite of path planning,elevator scheduling and resource allocation *** PMS aims to manage multiple concurrent requests,in real time and in a dynamic context,for storage and retrieval of vehicles loaded onto robotic carts for a fully automated,multi-story and driving-free parking *** algorithm suite employs the incremental informed search algorithm D*Lite with domain-specific heuristics and the uninformed search algorithm Uniform Cost Search for path search and *** optimization methodology based on nested partitions and Genetic algorithm is adapted for scheduling of a group of *** study considered a typical business day scenario in the center of a ***–The simulation study indicates that the proposed design for the PMS is able to serve concurrent storage-retrieval requests representing a wide range of Poisson distributed customer arrival rates in real time while requiring reasonable computing resources under realistic *** customer waiting times for both storage andretrievalrequestsare withinacceptable bounds,whichare set as nomore than 5min,evenin the presence of up to 100 concurrent storage and retrieval *** design is able to accommodate a variety of customer arrival rates and presence of immobilized vehicles which are assumed to be scattered across the floors of the structure to make it possible for deployment in real-time ***/value–The intelligent system design is novel as the fully automated robotic parking structures are just in the process of being matured from a techno

关键词： Robotic parking Automated parking Artificial intelligence Search Dynamic path planning,Scheduling Resource allocation Real-time system

Investigation of proton structure function F_(2)^(p)at HERA in light of an analytical solution to the Balitsky–Kovchegov equation

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Communications in Theoretical Physics 2024年第3期76卷 120-126页

作者： Ranjan Saikia Pragyan Phukan jayanta Kumar Sarma HEP laboratory Department of PhysicsTezpur UniversityTezpurAssam-784028India Department of Physics Moran CollegeMoranhatAssam-785670India

In this paper,the proton structure function F_(2)^(p)(x,Q^(2))at small-x is investigated using an analytical solution to the Balitsky–Kovchegov(BK)*** the context of the color dipole description of deep inelastic scattering(DIS),the structure function F_(2)^(p)(x,Q^(2))is computed by applying the analytical expression for the scattering amplitude N(k,Y)derived from the BK *** transverse momentum k and total rapidity Y,the scattering amplitude N(k,Y)represents the propagation of the quark-antiquark dipole in the color dipole description of *** the BK solution we extracted the integrated gluon density xg(x,Q^(2))and then compared our theoretical estimation with the LHAPDF global data fits,NNPDF3.1sx and ***,we have investigated the behavior of F_(2)^(p)(x,Q^(2))in the kinematic region of 10^(-5)≤x≤10^(-2)and 2.5 GeV^(2)≤Q^(2)≤60 GeV^(2).Our predicted results for F_(2)^(p)(x,Q^(2))within the specified kinematic region are in good agreement with the recent high-precision data for F_(2)^(p)(x,Q^(2))from HERA(H1 Collaboration)and the LHAPDF global parametrization group NNPDF3.1sx.

关键词： quantum chromodynamics(QCD) perturbative QCD(pQCD) proton structure function small-x Balitsky-Kovchegov equation

Small x phenomenology on gluon evolution through the BFKL equation in light of a constraint in multi-Regge kinematics

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Communications in Theoretical Physics 2020年第2期72卷 50-59页

作者： Pragyan Phukan Madhurjya Lalung jayanta Kumar Sarma HEP laboratory Department of PhysicsTezpur UniversityIndia

We investigate the impact of so-called kinematic constraint on gluon evolution at small *** the constraint on the real emission term of the gluon ladder diagram,we obtain an integro-differential form of the Balitsky-Fadin-Kuraev-Lipatov(BFKL)*** we solve the equation analytically using the method of *** sketch the Bjorken x and transverse momentum kt2 dependence of our solution of unintegrated gluon distributions f(x,kt2)in the kinematic constraint supplemented BFKL equation and contrasted the same with the original BFKL *** we extract the integrated gluon density xg(x,Q2)from unintegrated gluon distributions f(x,kt2)and compared our theoretical prediction with that of global data fits,namely NNPDF3.1 sx and *** we illustrate the phenomenological implication of our solution for unintegrated gluon distribution f(x,kT2)towards exploring high precision HERA DIS data by the theoretical prediction of proton structure functions(F2 and FL).

关键词： parton evolution equation gluon distribution function perturbative QCD

Non-invasive cuffless blood pressure and heart rate monitoring using impedance cardiography

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Intelligent Medicine 2022年第4期2卷 199-208页

作者： Sudipta Ghosh Bhabani Prasad chattopadhyay Ram Mohan Roy jayanta Mukherjee Manjunatha Mahadevappa Department of Computer Science&Engineering Indian Institute of Technology KharagpurKharagpurWest Bengal 721302India School of Medical Science&Technology Indian Institute of Technology KharagpurKharagpurWest Bengal 721302India Department of Cardiology Medical College&HospitalKolkataWest Bengal 700073India

Background Continuous blood pressure(BP)monitoring provides additional information about how changes in BP may correlate with daily activities and sleep *** from the American Heart Association and American College of Cardiology strongly suggest confirming a diagnosis of hypertension with continuous BP ***-invasive and non-intrusive detection of haemodynamic parameters is emerging as a norm,based on self-monitoring wearable medical *** have carried out several studies using non-invasive and continuous BP measurements as an alternative to conventional cuff-based *** this work,we proposed a novel method for cuffless estimation of BP using impedance cardiography(ICG).Methods We conducted a single-centre,cross-sectional study of 104 subjects(of whom 30 were categorized as controls and the remaining 74 as the disease group)at the Medical College and Hospital,*** disease group consisted of patients with confirmed coronary artery disease,while the individuals in the control group were deemed to be *** subjects underwent electrocardiogram recording by on-duty doctors in order to determine their health status.A custom-made device based on the principle of impedance plethysmography was designed to record impedance changes due to subjects’peripheral blood *** device was used to record ICG *** this study,we developed a novel auto-adaptive algorithm based on ICG signals for non-invasive,cuffless,continuous monitoring of BP and heart *** mathematical models were developed for all the estimated parameters(BP and heart rate)for both the study groups(control and disease).The developed models were auto-adaptive and did not require subject-specific *** indicators including,𝑟2,error percentage,standard deviation,and mean difference were used to quantify the performance of the *** The ICG signal recorded by the device was used to extract features and compute t

关键词： Impedance cardiography Augmentation index Systolic pressure Diastolic pressure Heart rate

Dengue and its effects on liver

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World Journal of Clinical Cases 2015年第2期3卷 125-131页

作者： jayanta Samanta Vishal Sharma Department of Gastroenterology Postgraduate Institute of Medical Education and Research

Dengue has emerged as an important arboviral disease with significant impact on the disease burden in population residing in tropical countries. Dengue is spread by the bite of Aedes mosquito. The virus seems to have some hepatotoxic effects. Affliction of liver in form of derangements in the liver function tests is common and may include mild elevations in serum bilirubin, elevated transaminases and derangements in serum albumin. Although asymptomatic in most cases, clinical manifestations like jaundice, and acute liver failure(ALF) may occasionally complicate the clinical picture. Indeed, dengue has been implicated as an important cause of ALF in endemic countries. The present review focuses on the hepatic manifestations and the pathogenesis of the liver injury in dengue.

关键词： Dengue Liver Viral hepatitis Acute liver failure Transaminases Bilirubin