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West Bengal, India

Jana D.K.,Haldia Institute of Technology | Das B.,Jhargram Raj College | Maiti M.,Vidyasagar University
Applied Soft Computing Journal | Year: 2014

In this paper, some multi-item inventory models for deteriorating items are developed in a random planning horizon under inflation and time value money with space and budget constraints. The proposed models allow stock dependent consumption rate and partially backlogged shortages. Here the time horizon is a random variable with exponential distribution. The inventory parameters other than planning horizon are deterministic in one model and in the other, the deterioration and net value of the money are fuzzy, available budget and space are fuzzy and random fuzzy respectively. Fuzzy and random fuzzy constraints have been defuzzified using possibility and possibility-probability chance constraint techniques. The fuzzy objective function also has been defuzzified using possibility chance constraint against a goal. Both deterministic optimization problems are formulated for maximization of profit and solved using genetic algorithm (GA) and fuzzy simulation based genetic algorithm (FAGA). The models are illustrated with some numerical data. Results for different achievement levels are obtained and sensitivity analysis on expected profit function is also presented. Scope and purpose The traditional inventory model considers the ideal case in which depletion of inventory is caused by a constant demand rate. However for more sale, inventory should be maintained at a higher level. Of course, this would result in higher holding or procurement cost, etc. Also, in many real situations, during a shortage period, the longer the waiting time is, the smaller the backlogging rate would be. For instance, for fashionable commodities and high-tech products with short product life cycle, the willingness for a customer to wait for backlogging diminishes with the length of the waiting time. Most of the classical inventory models did not take into account the effects of inflation and time value of money. But at present, the economic situation of most of the countries has been much deteriorated due to large scale inflation and consequent sharp decline in the purchasing power of money. So, it has not been possible to ignore the effects of inflation and time value of money any further. The purpose of this article is to maximize the expected profit of two inventory control systems in the random planning horizon. © 2014 Elsevier B.V. Source

Mukhopadhyay S.,Jhargram Raj College | Mondal S.,Indian Institute of Technology Kharagpur | Singh S.P.,Indian Institute of Technology Kharagpur | Date A.,Indian Institute of Technology Kharagpur | And 2 more authors.
Optics Express | Year: 2013

Large nonlinear phase shift achieved by exploiting intracavity second order cascaded nonlinear process in a non-phasematched second harmonic generating crystal is transformed into amplitude modulation through soft aperturing the nonlinear cavity mode variation within the laser gain medium to mode-lock a Nd:YVO4 laser. The laser delivers stable dual wavelength cw mode-locked pulse train with pulse duration 10.3 ps and average power of 1.84 W and 255 mW at 1064 nm and 532 nm respectively for a pump power of 12 W. A comprehensive theoretical analysis finds the regime of self starting and stable cascaded second order mode-locking, inconformity with the experimental result. © 2013 Optical Society of America. Source

Ojha A.,Vidyasagar University | Das B.,Jhargram Raj College | Mondal S.,Vidyasagar University | Maiti M.,Vidyasagar University
Applied Soft Computing Journal | Year: 2010

In this paper, discount in transportation cost on the basis of transportated amount is extended to a solid transportation problem. In a transportation model, the available discount is normally offered on items/criteria, etc., in the form AUD (all unit discount) or IQD (incremental quantity discount) or combination of these two. Here transportation model is considered with fixed charges and vechicle costs where AUD, IQD or combination of AUD and IQD on the price depending upon the amount is offered and varies on the choice of origin, destination and conveyance. To solve the problem, genetic algorithm (GA) based on Roulette wheel selection, arithmetic crossover and uniform mutation has been suitably developed and applied. To illustrate the models, numerical examples have been presented. Here, different types of constraints are introduced and the corresponding results are obtained. To have better customer service, the entropy function is considered and it is displayed by a numerical example. To exhibit the efficiency of GA, another method-weighted average method for multi-objective is presented, executed on a multi-objective problem and the results of these two methods are compared. Crown Copyright © 2009. Source

Das B.C.,Vidyasagar University | Das B.,Jhargram Raj College | Mondal S.K.,Vidyasagar University
Computers and Industrial Engineering | Year: 2013

This study develops an integrated production inventory model of supplier and retailer where a delay in payment is offered by supplier to retailer for a constant deteriorating item. Here shortages are not allowed. In this model retailer's procurement cost linearly depends on the credit period and supplier's process cost also is a linear function of the amount of quantity purchased by retailer. In this model, the objective is to decide the position of the credit period and number of replenishment of retailer in finite time horizon in such a way that the integrated system gets the optimum cost. The model is explained with the help of numerical examples and the sensitivity analysis of some parameters are also carried out. © 2013 Elsevier Ltd. All rights reserved. Source

Hazra D.K.,Indian Association for The Cultivation of Science | Chatterjee R.,Jhargram Raj College
Journal of Molecular Structure | Year: 2013

In situ solid state polymerization method was performed with mixtures of polyoxometalate (POM) and N-vinylcarbazole (NVC) in desired weight ratios for the synthesis of nanocomposites. The yield of the PNVC-H4SiW 12O40 nanocomposite increased with increasing amount of H4SiW12O40 as well as with [H 4SiW12O40]/[PNVC] loadings. The formation of PNVC in the system was endorsed by FTIR, UV-vis, and 1H1 NMR spectroscopic analyses. HRTEM studies revealed that the PNVC-H 4SiW12O40 nanoparticles have an average grain size of 62.13 nm and that the H4SiW12O40 nanoparticles are fairly well-dispersed in the composite matrix. SEM analysis shows the presence of agglomerates of nano particles embedded in the matrix. AC conductivity (σac)-frequency variation was constant for PNVC but showed an increasing trend with higher H4SiW12O 40:PNVC weight ratios in the composite. © 2013 Elsevier Ltd. All rights reserved. Source

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