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Transactions of Nonferrous Metals society of China 2012年第5期22卷 1001-1011页

作者： D.P.mondal Nidhi JHA Anshul BADkUL s.DAs Advanced Materials and Processes Research Institute(CsIR LAB) Bhopal 462064India

Aluminum-10% TiB master alloy was added in various proportions in 7178 Al alloy in order to examine the effect of TiB on grain refinement, wear and compressive deformation of the later one. Microstructural characterization reveals that TiB particles act as grain refiners for primary base alloy and result in globular dendrites. It was observed that the wear resistance and strength of the alloy decreased when the master alloy addition increased beyond 20%, even though the dendrites become much finer and almost spherical in nature.

关键词： aluminum alloys grain refinement Al-TiB master alloy compressive deformation sliding wear

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splicing operation and fuzzy molecular automaton

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International Journal of Intelligent Computing and Cybernetics 2012年第2期5卷 206-225页

作者： kumar s.Ray Mandrita mondal Electronics and Communication sciences Unit Indian Statistical InstituteKolkataIndia

Purpose–The purpose of this study is to develop a Turing machine or a finite automaton,which scans the input data tape in the form of DNA sequences and inspires the basic design of a DNA ***/methodology/approach–This model based on a splicing system can solve fuzzy reasoning autonomously by using DNA sequences and human assisted *** hardware consists of class IIs restriction enzyme and T4 DNA ligase while the software consists of double stranded DNA sequences and transition molecules which are capable of encoding fuzzy *** mixing solutions containing these components,the automaton undergoes a cascade of cleaving and splicing cycles to produce the computational result in form of double stranded DNA sequence representing automaton’s final ***–In this work,the authors have fused the idea of a splicing system with the automata theory to develop fuzzy molecular automaton in which 1,018 processors can work in parallel,requiring a trillion times less space for information storage,is 105 times faster than the existing super computer and 1,019 power operations can be performed using one Joule of ***/value–This paper presents a generalized model for biologically inspired computation in nano scale.

关键词： splicing operation Automaton Turing

spin-phonon decoherence in solid-state paramagnetic defects from first principles

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npj Computational Materials 2023年第1期9卷 1129-1136页

作者： sourav mondal Alessandro Lunghi school of Physics AMBER and CRANN InstituteTrinity CollegeDublin 2Ireland

Paramagnetic defects in diamond and hexagonal boron nitride possess a combination of spin and optical properties that make them prototypical solid-state *** the coherence of these spin qubits being critically limited by spin-phonon relaxation,a full understanding of this process is not yet *** we apply ab initio spin dynamics simulations to this problem and quantitatively reproduce the experimental temperature dependence of spin relaxation time and spin coherence *** demonstrate that low-frequency two-phonon modulations of the zero-field splitting are responsible for spin relaxation and decoherence,and point to the nature of vibrations in 2-dimensional materials as the culprit for their shorter coherence *** results provide an interpretation to spin-phonon decoherence in solid-state paramagnetic defects,offer a strategy to correctly interpret experimental results,and pave the way for the accelerated design of spin qubits.

关键词： phonon relaxation state

Integrating the Analytical Hierarchy Process(AHP) and the Frequency Ratio(FR) Model in Landslide susceptibility Mapping of shiv-khola Watershed,Darjeeling Himalaya

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International Journal of Disaster Risk science 2013年第4期4卷 200-212页

作者： sujit mondal Ramkrishna Maiti Department of Geography Raja N.L.Khan Women’s CollegePaschim MedinipurWest Bengal721102India Department of Geography and Environment Management Vidyasagar UniversityPaschim MedinipurWest Bengal721102India

To prepare a landslide susceptibility map of shivkhola watershed,one of the landslide prone parts of Darjeeling Himalaya,remote sensing and GIs tools were used to integrate 10 landslide triggering parameters:lithology,slope angle,slope aspect,slope curvature,drainage density,upslope contributing area(UCA),lineament,settlement density,road contributing area(RCA),and land use and land cover(LULC).The Analytical Hierarchy Process(AHP) was applied to derive factor weights using MATLAB with reasonable consistency ratio(CR).The frequency ratio(FR) model was used to derive class frequency ratio or class weights that indicate the relative importance of individual classes for each *** weighted linear combination(WLC) method was used to determine the landslide susceptibility index value(LsIV) on a GIs platform,by incorporating both factor weights and class *** shiv-khola watershed is classified into five landslide susceptibility *** overall classification accuracy is 99.22 and kappa statistics is 0.894.

关键词： weights susceptibility watershed

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Optimal harvesting of a prey-predator model with variable carrying capacity

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International Journal of Biomathematics 2017年第5期10卷 185-208页

作者： Chaity Ganguli T. k. kart P. k. mondal Department of Mathematics Indian Institute of Engineering science and Technology shibpur Howrah 711103 West Bengal India Department of Mathematics shibpur sri Ramkrishna Vidyalaya Howrah 711102 West Bengal India

This work deals with a prey-predator model in an environment where the carrying capacities are assumed to be variable with time and one species feeds upon the other. Independent harvesting efforts are applied in either species and asymmetrical intraguild predation occurs. A common resource is consumed by two competing species and at the same time predator also consumes the prey. At first we discuss the model under constant carrying capacity and make the conclusion that no limit cycle exists in this case. Then we discuss the model without intraspecific competition. Our main concern is to cover the above mentioned two cases together, i.e. the model with variable carrying capacity and intraspecific competition. We determine the steady states and examine the dynamical behavior. We also analyze the local and global stability of the interior equilibrium by Routh-Hurwitz criterion and a suitable Lyapunov function respectively. A Hopf bifur- cation occurs with respect to a parameter which is the ratio of predator＇s and prey＇s intrinsic growth rate. The possibility of bionomic equilibrium has been considered. The optimal harvest policy is formulated and solved with Pontryagin＇s maximum principle. some numerical simulations are given to explain most of the analytical results.

关键词： Variable carrying capacity intraguild predation Hopf bifurcation optimal harvesting.

Optimization of fused deposition modeling process parameters using a fuzzy inference system coupled with Taguchi philosophy

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Advances in Manufacturing 2017年第3期5卷 231-242页

作者： saroj kumar Padhi Ranjeet kumar sahu s. s. Mahapatra Harish Chandra Das Anoop kumar sood Brundaban Patro A. k. mondal Department of Mechanical Engineering Institute of Technical Education and Research Siksha 'O' AnusandhanUniversity Bhubaneswar 751030 India Department of Mechanical Engineering SRM UniversityKattankulathur 603203 India Department of Mechanical Engineering National Institute ofTechnology Rourkela 769008 India Department of Manufacturing Engineering National Instituteof Foundry and Forging Technology Ranchi 834003 India Department of Mechanical Engineering National Institute of Technology Warangal 506004 India

Fused deposition modeling （FDM） is an additive manufacturing technique used to fabricate intricate parts in 3D, within the shortest possible time without using tools, dies, fixtures, or human intervention. This article empiri- cally reports the effects of the process parameters, i.e., the layer thickness, raster angle, raster width, air gap, part orientation, and their interactions on the accuracy of the length, width, and thicknes, of acrylonitrile-butadiene- styrene （ABsP 400） parts fabricated using the FDM tech- nique. It was found that contraction prevailed along the directions of the length and width, whereas the thickness increased from the desired value of the fabricated part. Optimum parameter settings to minimize the responses, such as the change in length, width, and thickness of the test specimen, have been determined using Taguchi＇s parameter design. Because Taguchi＇s philosophy fails to obtain uniform optimal factor settings for each response, in this study, a fuzzy inference system combined with the Taguchi philosophy has been adopted to generate a single response from three responses, to reach the specific target values with the overall optimum factor level settings. Further, Taguchi and artificial neural network predictive models are also presented in this study for an accuracy evaluation within the dimensions of the FDM fabricated parts, subjected to various operating conditions. The pre- dicted values obtained from both models are in good agreement with the values from the experiment data, with mean absolute percentage errors of 3.16 and 0.15, respectively. Finally, the confirmatory test results showed an improvement in the multi-response performance index of 0.454 when using the optimal FDM parameters over the initial values.

关键词： Fused deposition modeling (FDM) ·Dimensional accuracy · Fuzzy logic · Performance characteristic · Multi-response performance index (MRPI)Artificial neural network (ANN)

Multi-scale analysis for transport of fine settling particles through an ice-covered channel in a laminar flow condition

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International Journal of sediment Research 2022年第6期37卷 794-808页

作者： subham Dhar Nanda Poddar B.s.Mazumder kajal kumar mondal Department of Mathematics Cooch Behar Panchanan Barma University Physics and Applied Mathematics Unit Indian Statistical Institute Department of Civil Engineering Indian Institute of Technology Bombay

The current research deals with the dispersion of fine settling particles in a fluid flowing through an icecovered channel under the laminar flow condition. An analytical solution of the two-dimensional convection-diffusion equation, based on the multi-scale homogenization technique, is obtained. To validate the current study, analytical results for the dispersion coefficient are compared with the available earlier research work. Moreover, the proposed analytical solutions for mean concentration distributions of the tracers are compared with the numerical results obtained from the finite difference technique. From the industrial and environmental points of view, the vertical concentration distribution provides a very significant information. The downstream evolution of the concentration distribution also is shown for typical time periods at different values of the settling velocity. The approach to the vertical uniformity shows that it is too slow a process in comparison to that of longitudinal normality. It was found that settling velocities of particles disturb the vertical uniformity and the centroid of the solute cloud rises due to the increase in settling velocity. Results illustrate that in the downstream direction, the vertical concentration distribution increases near the bed surface and it decreases in the proximity of the ice-covered surface of the channel with the increase of settling velocity, but the mean concentration of the solute increases. The current study may play an important role to understand the mechanism of the sedimentation process in a closed channel system.

关键词： sediment transport Dispersion Ice-covered channel Vertical uniformity Multi-scale analysis

Litterfall,decomposition and nutrient release of shorea robusta and Tectona grandis in a sub-tropical forest of West Bengal,Eastern India

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Journal of Forestry Research 2016年第5期27卷 1055-1065页

作者： Chittaranjan Das Naba kumar mondal Department of Environmental science The University of Burdwan

We studied leaf litter fall, decomposition and nutrient release patterns of shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha-1 a-1 for s. robusta to 11.03 ± 3.72 t ha-1 a-1 for T. grandis and the decay constant （k） of decomposed leaf litter was distinctly higher for T. grandis （2.70 ± 0.50 a-1） compared to s. robusta （2.41 ±0.30 a-1）. Biomass loss was positively correlated with the initial litter C, WsC, C/N and ash content in s. robusta and N, P and k concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for s. robusta and L, WsC, L/N and C/N ratio for T. grandis （P 〈 0.01）. Nutrient use efficiency （NUE） and nutrient accumulation index （NAI） of s. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P 〉 N 〉 k. Annual N, P and k input to soil through litterfall differed significantly between the two species in the following order： N〉k^P. s. robusta was superior in terms of k and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release （k 〉 P 〉 N） during decomposition of their leaf *** of N, k and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.

关键词： Decay constant Lignin Litterfall Nutrientreturn Decomposition Nutrient use efficiency

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Analytics of an Imperfect Four-Layer Production Inventory Model Under Two-Level Credit Period Using Branch-and-Bound Technique

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Journal of the Operations Research society of China 2022年第4期10卷 725-748页

作者： subrata Panja shyamal kumar mondal Department of Applied Mathematics with Oceanology and Computer Programming Vidyasagar UniversityMidnaporeW.B.721102India

This paper explains an integrated production inventory supply chain model,which consists of a supplier,a manufacturer and a retailer under two-level credit *** is manufacturer’s credit period offered by the supplier,and other is retailer’s credit period offered by the ***,the manufacturer replenishes raw materials from the supplier and produces non-deteriorating products in some cycles of equal *** is noted that here four inventory structures have been considered to show the flow of the materials as either raw materials or finished products from supplier to retailer via *** in this model,manufacturer’s imperfect production has been *** imperfect items are not *** retailer receives good finished products from the manufacturer and sells these to his/her customers during some cycles of equal length in total time *** main objective is to find the optimal number of production and business cycles of the manufacturer such that the integrated system can get the maximum *** above discussed model is elaborated with the help of a numerical example,and a sensitivity analysis is done with respect to some parameters used in this model.

关键词： supply chain Integrated production inventory Four-layer inventory system Imperfect production Two-level credit period

Bioconvection in Casson nanofluid flow with Gyrotactic microorganisms and variable surface heat flux

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International Journal of Biomathematics 2019年第4期12卷 111-135页

作者： I.s.Oyelakin s.mondal P.sibanda D.sibanda school of Mathematics Statistics and Computer Science University of KwaZulu-NatalPietermaritzburg Private Bag X01 Scottsville 3209 South Africa Department of Mathematics Amity University Kolkata New Town West Bengal 700135India school of Education University of KwaZulu-Natal Edgewood Private Bag X03 Pinetown 3605 South Africa

This paper presents a two-dimensional unsteady laminar boundary layer mixed convection flow heat and mass transfer along a vertical plate filled with Casson nanofluid located in a porous quiescent medium that contains both nanoparticles and gyrotactic microorganisms. This permeable vertical plate is assumed to be moving in the same direction as the free stream velocity. The flow is subject to a variable heat flux, a zero nanoparticle flux and a constant density of motile microorganisms on the surface. The free stream velocity is time-dependent resulting in a non-similar solution. The transport equations are solved using the bivariate spectral quasilinearization method. A grid independence test for the validity of the result is given. The significance of the inclusion of motile microorganisms to heat transfer processes is discussed. We show, inter alia, that introducing motile microorganisms into the flow reduces the skin friction coefficient and that the random motion of the nanoparticles improves the rate of transfer of the motile microorganisms.

关键词： Gyrotactic microorganisms bioconvection Casson nanofluid variable heat flux bivariate spectral quasilinearization method