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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

Analysis of a harvested tritrophic food chain model in the presence of additional food for top predator

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International Journal of Biomathematics 2018年第4期11卷 271-299页

作者： Prabir Panja Swarup Poria shyamal kumar mondal Department of Applied ScienceHaldia Institute of Technology Haldia-721657 West Bengal India Departmcnt of Applied MathematicsUniversity of Calcutta 92 APC Road Kolkata 700009 India Department of Applied Mathematics with Oceanology and Computer ProgrammingVidyasagar University Midnapore 721 102 West Bengal India

In this paper, we propose and analyze a three-species predator prey system in the presence of additional food for top predator. It is assumed that the middle predator is acting as a prey as well as a predator and the top predator consumes both prey as well as middle predator. It is also considered that a constant amount of additional food for top predator exists in the ecosystem. The effects of harvesting of top predator are investigated. The existence and stability conditions of the equilibria have been discussed analytically. The Hopf bifurcation analysis of the system with respect to predation rate of prey to the top predator and the harvesting effort have been analyzed both analytically and numerically. Pontryagin＇s maximum principle is used to determine the optimal harvesting of top predator population to maximize the discounted net revenue. From our analysis, it is seen that the additional food has a significant impact to prevent the extinction risk of top predator population and also to increase revenue collection. Finally, some numerical results have been given in support of our analytical findings.

关键词： Predator Prey Hopf bifurcation Pontryagin's maximum principle Harvesting.

An inventory model under development cost-dependent imperfect production and reliability-dependent demand

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Journal of Management Analytics 2017年第3期4卷 258-275页

作者： Barun Khara Jayanta kumar Dey shyamal kumar mondal Department of Applied Mathematics with Oceanology and Computer Programming Vidyasagar UniversityMidnaporeWBIndia Department of Mathematics Mahishadal Raj CollgePurba MedinipurWBIndia

This paper considers a model that deals with an imperfect production process where both perfect and imperfect quality items are ***,demand depends on selling price and reliability of the *** manufacturing company expects to produce perfect quality *** due to the long-run process,several kinds of problem such as labor,machinery,and technology *** a result,the manufacturing system becomes out-of-control state and consequently produces both perfect and imperfect quality *** items are ready to sell but imperfect items are reworked at a cost to become *** cost,reliability of the product and reliability parameter of the manufacturing system can be improved by introducing the development cost and also by improving the quality of the raw material of the production *** such circumstances,a profit function has been developed to find the optimum values of reliability parameter of the manufacturing system,reliability of the product and duration of production such that a manufacturer gets a maximum ***,the model has been illustrated with some numerical examples exploring the sensitivity analysis with respect to some parameters.

关键词： imperfect production production time reliability parameter reliability of product

A supply chain model for imperfect production system with stochastic lead time demand

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Journal of Management Analytics 2018年第4期5卷 309-333页

作者： Rabin kumar Mallick Amalesh kumar Manna shyamal kumar mondal Department of Applied Mathematics with Oceanology and Computer Programming Vidyasagar UniversityMidnaporeIndia

This study deals an integrated manufacturer-buyer supply chain system for imperfect production under stochastic lead time ***,defective rate has been followed as a function of production ***,the produced units have been inspected in order to screen the defective units but screening rate is less than the production rate and greater than the demand *** purchases the products from the ***,we assume that shortage during the lead time is permitted and demand during the shortage period is fully *** objective is to derive the optimal production rate,ordering quantity and to maximize joint total ***,two different models for different probability distribution functions of stochastic lead time demand have been *** numerical examples are provided to show the applicability of the proposed models comparing the optimum average ***,sensitive analysis,conclusion and future researches are presented.

关键词： supply chain imperfect production stochastic lead time demand back order

Multi-item EPQ model with learning effect on imperfect production over fuzzy-random planning horizon

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Journal of Management Analytics 2017年第1期4卷 80-110页

作者： Amalesh kumar Manna Barun Das Jayanta kumar Dey shyamal kumar mondal Department of Applied Mathematics with Oceanology and Computer Programming Vidyasagar UniversityMidnapore-721102WBIndia Department of Mathematics Sidho-Kanho-Birsha UniversityPuruliaWBIndia Department of Mathematics Mahishadal Raj CollegeMahishadal721628WBIndia

Uncertainty is certain in the world of *** study revisits an economic production quantity(EPQ)model with shortages for stock-dependent demand of the items with reworking and disposing of the imperfect ones over a random planning horizon under the joint effect of inflation and time value of money,where the expected time length is imprecise in *** of learning effect has been incorporated to reduce the defective *** total expected profit over the random planning horizon is maximized subject to the imprecise space *** possibility,necessity and credibility measures have been introduced to defuzzify the *** simulation-based genetic algorithm is used to make decision for the above EPQ model in different measures of *** model is illustrated through an *** analysis shows the impacts of different parameters on the objective function in the model.

关键词： imperfect production rework shortage learning effect random planning horizon genetic algorithm

Evaluation of the CROPGRO-Peanut model in simulating appropriate sowing date and phosphorus fertilizer application rate for peanut in a subtropical region of eastern India

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作物学报：英文版 2017年第4期5卷 317-325页

作者： Debjani Halder Rabindra kumar Panda Rajiv kumar Srivastava shyamal Kheroar Department of Agriculture Government of West Bengal Mathabhanga Cooch Behar 736 146 West Bengal India School of Infrastructure Indian Institute of Technology Bhubaneswar 751 013 Odisha India Agricultural and Food Engineering Department Indian Institute of Technology Kharagpur 721 302 West Bengal India Department of Agronomy Uttar Banga Krishi Viswavidyalaya Pundibari Cooch Behar 736 165 West Bengal India

Projected changes in weather parameters, mainly temperature and rainfall, have already started to show their effect on agricultural production. To cope with the changing scenarios, adoption of appropriate management strategies is of paramount importance. A study was undertaken to evaluate the most appropriate combination of sowing date and phosphorus fertilization level for peanut crops grown in sandy loam soil in a subhumid region of eastern India. Field experiments were conducted during the summer seasons of 2012 and 2013 on peanut crops at the farm of the Indian Institute of Technology, Kharagpur. The DSSAT v4.5 CROPGRO-Peanut model was used to predict the phenology, growth, and yield of peanut crop under combinations of four sowing dates and four phosphorus fertilization levels. The model was calibrated with a 2012 dataset of growth, phenology, and yield parameters for estimating the genetic coefficients of cultivar TMV-2 and was validated with a 2013 dataset of the same parameters. Simulations of pod yield and other yield parameters using the calibrated model were found to be quite accurate. The model was able to reasonably simulate pod yield and final biomass with low normalized root mean square error (RMSE_n), low absolute root mean square error (RMSE_a) and high coefficient of determination (R^2> 0.7) over a wide range of sowing dates and different phosphorus fertilization levels sensitivity analysis indicated that sowing from the second week of January to the end of February with 30–50 kg P_2O_5 ha^(-1)would give the highest pod yield.

关键词： Sowing date Phosphorus fertilizer CROPGRO-Peanut model Sensitivity analysis RMSE

Gut dysfunction in Parkinson's disease

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World Journal of Gastroenterology 2016年第25期22卷 5742-5752页

作者： Adreesh Mukherjee Atanu Biswas shyamal kumar Das Department of Neurology Bangur Institute of Neurosciences and Institute of Post Graduate Medical Education and Research

Early involvement of gut is observed in Parkinson’s disease (PD) and symptoms such as constipation may precede motor symptoms. α-Synuclein pathology is extensively evident in the gut and appears to follow a rostrocaudal gradient. The gut may act as the starting point of PD pathology with spread toward the central nervous system. This spread of the synuclein pathology raises the possibility of prion-like propagation in PD pathogenesis. Recently, the role of gut microbiota in PD pathogenesis has received attention and some phenotypic correlation has also been shown. The extensive involvement of the gut in PD even in its early stages has led to the evaluation of enteric α-synuclein as a possible biomarker of early PD. The clinical manifestations of gastrointestinal dysfunction in PD include malnutrition, oral and dental disorders, sialorrhea, dysphagia, gastroparesis, constipation, and defecatory dysfunction. These conditions are quite distressing for the patients and require relevant investigations and adequate management. Treatment usually involves both pharmacological and non-pharmacological measures. One important aspect of gut dysfunction is its contribution to the clinical fluctuations in PD. Dysphagia and gastroparesis lead to inadequate absorption of oral anti-PD medications. These lead to response fluctuations, particularly delayed-on and no-on, and there is significant relationship between levodopa pharmacokinetics and gastric emptying in patients with PD. Therefore, in such cases, alternative routes of administration or drug delivery systems may be required.

关键词： Parkinson’ s disease Gut dysfunction Sialorrhea Dysphagia Gastroparesis Constipation Gut microbiota

Experimental Study of Perfectly Patterned Silica-Titania Optical Waveguide

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Photonic Sensors 2012年第1期2卷 81-91页

作者： Rimlee DEB ROY Devika SIL Sunirmal JANA Prasanta kumar BISWAS shyamal kumar BHADRA Fiber Optics & Photonics Division Central Glass & Ceramic Research Institute 196 Raja S. C. Mullick Road Jadavpur Kolkata-700 032 India Sol-Gel Division Central Glass & Ceramic Research Institute 196 Raja S. C. Mullick Road Jadavpur Kolkata-700 032 lndia Department of Chemistry Temple University Philadelphia PA 19122 USA

Inorganic silica-titania thin films with thicknesses 150 nm-200 nm are deposited on high purity and polished silicon wafer and silica glass substrates by sol-gel dipping process and are patterned by capillary force lithography technique. Subsequently grating structure is embossed in green stage. The patterned gel films are subjected to stepwise heat treatment to 500 ℃ and above in pure oxygen atmosphere in order to achieve major conversion of mixed-gel to oxide optical films which are characterized by Ellipsometry, Fourier transform infrared spectroscopy （FTIR） and atomic force microscopy （AFM） to optimize the fabrication parameters and to get perfectly matched film. Removal of organics and formation of perfectly inorganic silica-titania network at optimized heat treatment in controlled environment are ensured by FTIR spectral study. The difference in refractive indices between the substrate and coated film as developed waveguides for operating wavelength show the planar waveguide behavior of the films. calculated theoretically matches exactly with the （632.8 nm） and the measured optical properties

关键词： Optical properties sol-gel technique thin films oxides

Amyotrophic lateral sclerosis: promising therapeutic outcome–not far away?

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Neural Regeneration Research 2016年第5期11卷 856-856页

作者： Adrija Hajra Dhrubajyoti Bandyopadhyay shyamal kumar Hajra Department of Internal Medicine IPGMERKolkataIndia Department of Accident and Emergency Lady Hardinge Medical CollegeNew DelhiIndia

Dear editors,Amyotrophic lateral sclerosis（ALS）is a neurodegenerative *** affects motor neurons in the brain and spinal cord resulting in bulbar palsy and respiratory *** also causes weakness of *** disease usually progresses to fatal outcome within 2-4 *** stem cell research for diagnosis and treatment of neurodegenerative disorders is highly promising.

关键词： MSCs cell not far away promising therapeutic outcome NCT