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This paper presents the designing of two Swastik-shaped patch antennas operating at 5.8GHz which is designated for IEEE802.11b WLAN communications. The first proposed antenna is designed on a single layer of Rogers RO4350 resulting in a narrowband response of bandwidth 60MHz. The second proposed antenna is designed as two layered (air, Rogers RO4350) structure and has resulted in improved bandwidth. The obtained bandwidth is 210MHz which is 3.5 times of the bandwidth of the first antenna. The antennas are probe feeded. The Ansoft HFSS is employed for designing the antenna [ABSTRACT FROM AUTHOR]

ABS methods have been studied a lot in last few years . This paper gives a review of work done by few researchers for applying ABS algorithm for different problems i.e; for solving determined or undetermined linear systems , linear least square optimization problem and integer equations and linear programming problems. [ABSTRACT FROM AUTHOR]

Considerable amount of analytic work has been done for the case where the enterprise has got one warehouse, but little work has been done for the case where an enterprise has got more than one warehouse. In the present paper, we consider a situation where the enterprises have got two warehouses. In the proposed model, the demand rate is taken as a time and stock dependent. Shortages are allowed and partial backlogged and the backlogging rate is variable and is dependent on the length of the waiting time for the next replenishment. The longer the waiting time is the smaller the backlogging rate would be. Effect of inflation on the model also considered. A numerical example with sensitivity analysis is given to validate the results of the proposed model. [ABSTRACT FROM AUTHOR]

Trade credit financing has become a powerful tool to improve demand and profit in industry. In general, a supplier/retailer frequently offers trade credit to its credit risk downstream member in order to stimulate their respective demand. The main purpose of the present paper is to explore the impact of credit period on the retailer's demand, which may be instant or delayed. An EPQ model under the condition of two echelon trade credit with credit sensitive demand has been analyzed. This type of demand pattern can be observed in many consumer durables. The optimal credit period offered by the retailer and the optimal replenishment time has been jointly evaluated in order to maximize retailer's profit. Results have been validated with the help of examples. Comprehensive sensitivity analysis has been performed on different parameters. [ABSTRACT FROM AUTHOR]

In this paper a two-warehouse inventory model for deteriorating items with partial backordering and time as well as stock dependent demand has been developed. The rate of deterioration of items in the two warehouses follows Weibull distribution. We consider inflation in problem analysis. Also, a single warehouse version for deteriorating items is discussed. We show that the total cost of the system is influenced by the deterioration rate, the inflation rate and the backordering ratio. Most researchers on inventory models do not consider simultaneously the phenomena with two-warehouse, varying rate of deteriorating, inflation and partial backordering. Since these phenomena are not uncommon in real life, we incorporate them in our problem development. [ABSTRACT FROM AUTHOR]

In this paper, we focused on the scheduling and sequencing which is a form of Decision Making (DM) that plays a crucial role in production manufacturing and service industries. Job- scheduling problem arise when there is a choice as to the order in which number of tasks can be performed. In such problems, we determine an appropriate order or schedule for a series of jobs to be done on a finite number of service facilities. The paper presents the way of makingschedule of a finite number of jobs on a finite number ofmachines of unequal efficiencies by using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) Method in fuzzy environment. The order of machinesis random. The time taken by the machines for conducting jobsis assumed as imprecise processing time or fuzzy numbers. The fuzzy evaluation values are given by Triangular FuzzyNumbers (TNFs). Weights are given to each machine according totheir efficiency. A new distance is defined using which thedistance of each job from the positive and negative idealsolutions are calculated. Also a closeness coefficient isdefined to determine the ranking order of the jobs so that thecomplete schedule or sequence may finish at minimum time-span. Finally, anumerical example is illustrated for proposed method. [ABSTRACT FROM AUTHOR]

In this paper, we derive necessary and sufficient conditions for differentiable multiobjective fractional Minimax Programming under vector η-generalized convex functions and also weak and strong duality results have been proved. [ABSTRACT FROM AUTHOR]

Probabilistic or Stochastic programming is a framework for modeling optimization problems that involve uncertainty. The basic idea used in solving stochastic optimization problems has so far been to convert a stochastic model into an equivalent deterministic model and is possible when the right hand side resource vector follows some specific distributions such as normal, lognormal and exponential distributions. In this paper, a multi-objective stochastic programming problem has been considered with right hand side resource vector following general form of distributions …, which include many distributions such as Power Function distribution, Pareto distribution, Beta distribution of first kind, Weibull distribution, and Burr type XII distribution. In this approach, the multi-objective stochastic programming problem is converted into an equivalent deterministic model, which is then solved by a multi-objective programming genetic algorithm using Matlab. Few numerical examples are presented to illustrate the proposed approach. [ABSTRACT FROM AUTHOR]

The programming problem considered in this work has a linear--plus-linear fractional absolute value objective function with unrestricted variables. Mathematically this problem can be stated as: Maximize … Subject to A x = b, is x is unrestricted. Adjacent extreme point (simplex-type) methods proposed by Teterev [13] cannot be used to solve this class of problems. However, this paper explores the conditions under which extreme point algorithms can be used to arrive at a desired solution for a linear--plus-linear fractional programming absolute value objective function problem with unrestricted variables. [ABSTRACT FROM AUTHOR]

In this paper an inventory model is developed in which shortages are considered with two-storage under inflation induced demand rate. Due to different preservation environment it is assumed that in one warehouse deterioration rate is time varying linear and in the other it is taken as Weibull distributed deterioration. The classical optimization technique is used to drive the optimal solution. Finally, some numerical examples for illustration are provided. [ABSTRACT FROM AUTHOR]

Begum et al. (DOI: 10.1080/00207721.2010.543481) developed replenishment policy when demand rate is price-sensitive, deterioration rate follows three parameters, Weibull distribution and shortages are not allowed. In the paper it is observed that that the retailer's inventory stock is zero before the deterioration of units start. This article rectifies the model formulation. The remodel is validated with a numerical example and the sensitivity analysis of parameters is carried out. [ABSTRACT FROM AUTHOR]

This paper deals with the applications of Response Surface Methodology (RSM) on the effect of microwave heat treatment for mullite formation from placer sillimanite. The results of these investigations reveal that RSM data obtained from microwave heat treatment studies show that there is 92.55% of mullite formation under optimized conditions with composite charge material having 40% Al2O3, 60% sillimanite, with additive 60% SiC and 10% binder. The confirmatory experimental data of RSM optimised conditions also suggest that there is 97% of mullite formation using microwave heat treatment. A mullite is formed within 25 minutes from the sillimanite, under the above experimental conditions. FESEM image analysis shows the mullite formations in cluster form, SiC in massive structure and alumina needle form in microwave treated sample. Thus microwave heat source is much effective to form mullite from sillimanite. [ABSTRACT FROM AUTHOR]

This paper presents bicriteria in n-jobs, three machines flow shop scheduling problem to minimize the total elapsed time and rental cost of the machines under a specified rental policy in which the processing time, independent setup time each associated with probabilities including transportation time and job block concept. Further the concept of the break down interval for which the machines are not available for the processing is included. A heuristic approach method to find optimal or near optimal sequence has been discussed. A computer programme followed by a numerical illustration is given to substantiate the algorithm. [ABSTRACT FROM AUTHOR]

In this paper, we focused on the scheduling and sequencing which is a form of Decision Making (DM) that plays a crucial role in production manufacturing and service industries. Job-scheduling problem arise when there is a choice as to the order in which number of tasks can be performed. In such problems, we determine an appropriate order or schedule for a series of jobs to be done on a finite number of service facilities. The paper presents the way of making schedule of a finite number of jobs on a finite number of machines of unequal efficiencies by using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) Method in fuzzy environment. The order of machines is random. The time taken by the machines for conducting jobs is assumed as imprecise processing time or fuzzy numbers. The fuzzy evaluation values are given by Triangular Fuzzy Numbers (TNFs). Weights are given to each machine according to their efficiency. A new distance is defined using which the distance of each job from the positive and negative ideal solutions are calculated. Also a closeness coefficient is defined to determine the ranking order of the jobs so that the complete schedule or sequence may finish at minimum time-span. Finally, a numerical example is illustrated for proposed method. [ABSTRACT FROM AUTHOR]

In this paper an integrated inventory model for decaying items with exponential demand has been developed. The inventory is allowed to deteriorate during the time it is stored and during this time it undergoes Weibull rate of deterioration. Partially backlogged shortages are permitted with constant backlogging rate. The effect of inflation is also taken in this study. Production rate is taken as demand dependent. Numerical results are presented and discussed to demonstrate the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

In the present paper an order level inventory model for deteriorating items with multi dependent consumption rate under the inflationary conditions has been developed. We have taken a more realistic demand rate that depends on two factors, one is time, and the other is the stock level. The stock level in itself obviously gets depleted due to the customer's demand. In this model , shortages are allowed with complete backlogging. The results have been illustrated with the help of numerical example. [ABSTRACT FROM AUTHOR]

Inventory may be considered as an accumulation of a product that would be used to satisfy future demands for that product. In this paper an inventory model with two warehouses for deteriorating items with shortages is developed. We took the exponential demand and linear deterioration rate of inventory items in OW and RW. A number of structural property of the inventory system studied analytically. [ABSTRACT FROM AUTHOR]

In this paper an inventory system is developed for deteriorating items with multi-variate demand. Here, demand rate is a function of time, stock and selling price. In this study, we have taken production rate is demand dependent. We have also considered the situation, when the retailer has the reserve money but still wants to avail the facility of progressive credit period. Shortages are allowed in inventory which is completely backlogged. An optimization framework has been presented, which derives optimal ordering policies when the present values of total cost has been optimized. [ABSTRACT FROM AUTHOR]

In this paper a production inventory model is developed in which the production rate at any instant depends on the demand and the inventory level. The holding cost is an exponential increasing function of time. The effects of the time value of money are taken into the consideration. The demand rate is a linear function of time for the scheduling period. Through numerical example, sensitive analyses are carried out to examine the effect of the parameters. Results show that the discount rate parameter and the inventory holding cost have a significant impact on the proposed model. [ABSTRACT FROM AUTHOR]

In this paper, a generalized fractional programming problem with linear constraints and the objective function is the sum of the functions of the form Minimize … Subject to the linear constraints Ax ≥ b, and x ≥ 0 where a'x+p , c'x + q and e'x + r are linear functions has been discussed. Solution of the above generalized fractional programming problem can be recovered by reducing it to a fractional programming problem. [ABSTRACT FROM AUTHOR]

This paper details the application of linear programming and transportation model in a power generation company for optimizing the coal purchase plan. The company -- a private sector utility company in India-purchases coal using base tonnage with certain tolerance on lower or higher side from different sources around the world and the coal needs to be shipped from the supplier's mines to the company's generating facilities. Company would like to have the optimum solution for coal allocations considering the various possible scenarios in the next five years. Based on LP Transportation model, a base coal allocation model is first developed to optimize the purchase of coal from different sources and allocation to different generating facilities. The technical constraints and cost elements are considered in each year with necessary modifications as required for the new plants coming on stream. The model is further extended to calculate the optimum coal allocation which minimizes the total purchase cost in case quantity discount is offered by different sources. Further, cost escalations due to various uncertainties - in clearance of shipments at ports, which may cause delays in transportation - are also considered and the model is extended to include the effect of the same on the allocation and total cost. This has been done with help of Risk Premium Solver. The model can be further tweaked to include constraints on pollution control based on quality of coal (ash content, sulphur content etc.). The coal cost optimization model can also be extended to include simulation with appropriate simulation software like Witness, as done by Yabin Li. [ABSTRACT FROM AUTHOR]

Over the past three decades, intensive research on marine oil spill pollution control has been directed toward the development of mathematical models to predict and forecast the fate and transport of spilled oil and oil products in marine environments. Such research has been focused on selecting locations for the deployment of containment and collection systems to mitigate the effects of spilled oil on the environment. These models can be used for short-term tactical forecasting to help make decisions to contain, control and clean up accidental spill, however, they are not comprehensive for rapid response with regards to the clean up combating techniques strategy and also not accurate for spills detection. This paper proposes an operational research technique via optimal control theory and sequential decision processes as an alternative tool for optimal spill pollution control. [ABSTRACT FROM AUTHOR]

Interval-parameter two-stage stochastic programming is an optimization problem by incorporating some of the input model parameters as random variables with known probability distributions and discrete intervals simultaneously within the two-stage stochastic optimization framework. In this paper, we proposed an interval-parameter two-stage stochastic programming problem considering only the right hand side parameters of the constraints as exponential random variables with known mean and variance and all other parameters are discrete intervals. Both the random variables and discrete intervals are simultaneously conceived under one roof for the model parameters. In order to solve the problem, first we remove the randomness from the problem and formulate an equivalent deterministic interval non-linear programming model. Then the deterministic interval non-linear programming model is solved and find the interval optimal solutions which provides several alternatives that reflect different decisions. A numerical example is presented to exemplify the usefulness of the proposed methodology. [ABSTRACT FROM AUTHOR]

In this paper, an inventory model for non-instantaneous deteriorating items with stock-dependent consumption rate has been developed. The competitive nature of the market has been accounted for by taking inflation into consideration. The model is developed for a finite planning horizon, keeping in mind the short lifespan of the customer's preferences. An optimization frame work is presented to derive optimal replenishment policy when the present value of total cost is minimized. Numerical examples are provided to illustrate the optimization procedure. In addition, the sensitivity analysis of the optimal solution with respect to parameters of the system is carried out. [ABSTRACT FROM AUTHOR]

The present paper undertakes to study integrated network of queues with service parametric constants. There are three types of servers S1, S2 and S3 in which S1, S2 and S3 is different from each other. For this we had taken five service channels which may be useful in any economical decision measure. The study is based on probabilities for their comparative work. The mathematical formulation of steady state situation is formed in terms of difference equation. The generating function technique has been adopted for the solution for the above set of model. Marginal Mean Queue Length, Mean Queue Length is also analyzed in this study. We can obtain other decision making parameters which can be used in the economical decision wherever this model can be applied [ABSTRACT FROM AUTHOR]

In the present paper we study two generalizations of Shannon's Inequality and their applications in source coding. We define two new generalized mean code word lengths and study their bounds in terms of the generalized measures of entropies obtained by applying these generalizations. Particular cases are also obtained. [ABSTRACT FROM AUTHOR]

This paper proposes and examines several swap strategies for the sugar industry to create win-win situations for industries supplying sugar to their customers. A realistic data from three sugar mills of Uttar Pradesh, Maharashtra and Bihar is used to build a number of linear programming models of the strategies under investigation. The optimal solutions of these models are analysed to identify the strategies advantages or disadvantages. The success of swap strategies relies on alliances and partnerships between the sugar industries. They, however, seem to advocate very attractive alternative policies, create potentials for substantial cost savings and assure more reliable lead- time to delivery. [ABSTRACT FROM AUTHOR]

This paper is an attempt to study a bicriteria in n jobs m machines flow shop scheduling problems under a specified rental policy in which processing times are associated with probabilities. We consider bi-criteria scheduling problems involving minimization of rental cost of the machines with minimum makespan. A heuristic approach to find the best possible sequence by optimizing both the criteria's simultaneously is discussed. The effectiveness of the heuristic approach is justified by mathematical proofs and bi-criteria In- Out flow table of the jobs. A computer programme followed by a numerical illustration is given to substantiate the algorithm. [ABSTRACT FROM AUTHOR]

Kaul and Kaur [7] obtained necessary optimality conditions for a non-linear programming problem by taking the objective and constraint functions to be semilocally convex and their right differentials at a point to be lower semi-continuous. Suneja and Gupta [12] established the necessary optimality conditions without assuming the semilocal convexity of the objective and constraint functions but their right differentials at the optimal point to be convex. Suneja and Gupta [13] established necessary optimality conditions for an efficient solution of a multiobjective non-linear programming problem by taking the right differentials of the objective functions and constraint functions at the efficient point to be convex. In this paper we obtain some results for a properly efficient solution of a multiobjective non-linear fractional programming problem involving semilocally convex and related functions by assuming generalized Slater type constraint qualification. [ABSTRACT FROM AUTHOR]

A deteriorating inventory model taking into account the linear deteriorating rate of items, is developed for a deteriorating inventory system with linear time dependent demand. In this model, shortages are allowed with partial backlogging. Demand is a linear function of time and deterioration rate is also linear function of time. As a result in this paper, we establish a model to find the optimal order quantity by minimizing the total inventory cost. Sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out. [ABSTRACT FROM AUTHOR]

In this paper a two-warehouse supply chain inventory model with inflation induced demand is developed. we have assumed the inventory costs including holding cost and deterioration cost in RW are higher than those in OW. The effect of permissible delay in payments has been taken in to account. Shortages are allowed with complete backlogged. Production rate is considered as demand dependent in vendor model. Holding cost is taken as variable. We believe that our study will provide a solid foundation for the further study of this sort of important inventory models. A numerical example is given to illustrate the system. [ABSTRACT FROM AUTHOR]

In this Paper, a coordinated system for supplier, producer and retailer has been discussed for optimal collection, material control, production control and ordering policies of a deteriorating product deteriorating linearly with time. The demand rate and the production rate are considered as linear functions of time. The deterioration rate is considered of Weibull distribution form given by αβtβ-1 where α > 0 and β > 1 constant. Both cases of shortages and without shortages are considered. The shortage is considered as fully backlogged. [ABSTRACT FROM AUTHOR]

A single layer compact size Swastik-shaped microstrip patch antenna is designed and studied. The antenna is designed to cover the frequency band designated for IEEE802.11 b for WLAN applications. The proposed antenna has simulated return loss of -29.5dB at 5.8GHz frequency. The peak gain of this antenna at resonance frequency is 1.6dB. The antenna is probe feeded. The Ansoft HFSS is employed for the antenna design. [ABSTRACT FROM AUTHOR]

The Economic Production Quantity (EPQ) model is commonly used by practitioners in the fields of production and inventory management to assist them in making decision on production lot size. The common assumptions in this model are that all units produced are perfect and shortages are not allowed. But, in real situation the defective items will be produced in each cycle of production and shortages and scrap are possible. These assumptions will underestimate the actual required quantity. Hence, the defective items can not be ignored in the production process. Rework process is necessary to convert those defective into finished goods. This study proposes EPQ model that incorporates both imperfect production quality and falsely not screening out a proportion of defects, thereby passing them on to customers, resulting in defect sales returns. Two models of rework processes are considered; the EPQ model without shortages is studied first and with shortages is investigated next. To active this objective a suitable mathematical model is developed and the optimal production lot size which minimizes the total cost is derived. The relevant model is built, solved and necessary and sufficient conditions for a unique and global optimal solution are derived. An illustrative example is provided and numerically verified. The validation of result in this model was coded in Microsoft Visual Basic 6.0. [ABSTRACT FROM AUTHOR]

A look at the literature available on inventory reveals that several models have been formulated in a static environment. An inventory model for time dependent deterioration of units is formulated to determine the optimal ordering policy when the supplier offers a credit period linked to order quantity to settle the accounts. The environment of the whole study has been taken as inflationary. [ABSTRACT FROM AUTHOR]

Consider a single channel two station tandem queue such that no queue is allowed in front of station 1 but at most one customer is allowed to wait in between station 1 and station 2 and with blocking. Assuming that the arrival process and the service process are dependent, we obtain the steady state solution for the system when the joint distribution of interarrival time, service time at station 1 and service time at station 2 is trivariate exponential. Also, the moment and CAN estimators and asymptotic confidence limits for the expected number of customers in the system are obtained. [ABSTRACT FROM AUTHOR]

In the growing area of interconnected computer, security is very essential task. Security in its most basic meaning is the protection from intruders. Therefore the issue of security metrics has seen considerable activity in recent times, and there are numerous approaches to monitoring and measuring "security" available. However, the majority of these efforts generally apply to subsections of technical, or IT, security with a few notable exceptions. While these technical metrics are in many cases very effective at the specific task for which they were designed, they say little about the overall security, or safety, of the organization and provide little guidance for effective management. Measuring the state of "safety" of an organization is vastly broader than knowing how many packets a firewall dropped and is typically well beyond the scope of IT, or for that matter, information security. [ABSTRACT FROM AUTHOR]

Three fundamental factors that determine the rate of growth of a nation are efforts, capital and knowledge. Among these, increasing capital formation has been considered as the most important factor in forecasting economic growth especially of the underdeveloped economies. To balance the requirement for over all developmental and to cater the apatite of expanding economies, financial institutions and capital markets in India and abroad emerged to mitigate the chronic problem of inadequacy of long term funds. The past decade in many ways has witnessed tremendous market sentiment in India. It has grown radically a battery of financial institutions stock exchanges and other intermediaries at the country and state level came into existence, amount raised from the market, the number of listed stocks, market capitalization, trading volumes and turnover on stock exchanges, and investor population. Despite the expansion of the securities market and reformatory measures taken by the GOI very small percentage of household savings are chanalized into the securities market. This indicates a lack of awareness and lingering confidence of the investors in the securities market. Primary objective of investing reserves in securities by the investors is to maximize earnings and to keep funds liquid and safe. The astute investment policy involves setting out investment objective, reviving investment needs of the investors, relevant policy guidelines with respect to size of the investment portfolio, approach of investment portfolio, effective portfolio diversification, maturity of the investment trading in securities, switching etc. Constructed portfolios should be revisited time and again in the light of external and internal developments and desired changes should be made in order to achieve optimum results. Thus, the present study tried to asses the applicability of Sharpe's single Index Model in Indian security market and to analyze construction of optimal portfolios with minimum and maximum return. By using Treynor Measure, Sharpe Measure, Jensen Measure, Fama's Measure, constructed portfolio which can work in Indian Security Market optimally. For the study purpose past 4 four years daily base data has been taken of renowned one benchmark 30 stocks BSE sensitive Index containing different Indian stocks. Considered input values for the model are the security returns, unsystematic variance of security return, beta values of securities and market variance. [ABSTRACT FROM AUTHOR]

So far, most work has been done under assumption that supplier offered to the retailer a fixed delay period, in settling accounts. The main purpose of this chapter is to investigate the retailer's optimal replenishment policy for life time items under two-level delay permitted to reflect the supply chain management situation. In which retailer also offered to his customer a fixed delay period, called the customer's credit period, in settling his account. Demand rate depend on the customer's credit period offered by the retailer. Shortages are allowed and partial backlogged and also depend on the customer's credit period offered by the retailer. Furthermore, numerical example is given to illustrate the results with sensitivity analyses develop in this study. [ABSTRACT FROM AUTHOR]

fashionable commodities and high-tech products with short product life cycle, the willingness of a customer to wait for backlogging is diminishing with the length of the waiting time. Thus the length of the waiting time for the next replenishment would determine whether the backlogging would be accepted or not. In many real life situations, during a shortage period, the longer the waiting time is, the smaller is the backlogging rate would be. Therefore, for realistic business situations the backlogging rate should be variable and dependent on the waiting time for the next replenishment. [ABSTRACT FROM AUTHOR]