Loading...
Search for:
discount
0.006 seconds
Total 52 records
A polynomial time branch and bound algorithm for the single item economic lot sizing problem with all units discount and resale [electronic resource]
, Article International Journal of Optimization in Civil Engineering ; 2012, 2(2): 183-202 ; Shadrokh, Sh ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
The purpose of this paper is to present a polynomial time algorithm which determines the lot sizes for purchase component in Material Requirement Planning (MRP) environments with deterministic time-phased demand with zero lead time. In this model, backlog is not permitted, the unit purchasing price is based on the all-units discount system and resale of the excess units is possible at the ordering time. The properties of an optimal order policy are argued and on the basis of them, a branch and bound algorithm is presented to construct an optimal sequence of order policies. In the proposed B&B algorithm, some useful fathoming rules have been proven to make the algorithm very efficient. By...
Order allocation in a multiple-vendor and quantity discount environment: A multi-objective decision making approach
, Article Management Science Letters ; Volume 8, Issue 10 , 2018 , Pages 975-990 ; 19239335 (ISSN) ; Jahromi, A. E ; Soleimani, M ; Sharif University of Technology
Growing Science
2018
Abstract
Integrated supplier selection and order allocation is a complex problem that is important for both designing and operating supply chains. It becomes especially complicated when quantity discounts are considered at the same time. Under such circumstances, most studies often formulate the problem as a Multi-Objective Linear Programming problem (MOLP), and then transform it to a Mixed Integer Programming problem (MIP) to handle the inherited multi-objectives, simultaneously. But, objectives are not of equal importance and in this approach scaling and subjective weighting often are not considered. In addition, some of the studies that use weighting method to solve the MOLP, usually ignore to...
Multi-product multi-constraint inventory control systems with stochastic replenishment and discount under fuzzy purchasing price and holding costs
, Article American Journal of Applied Sciences ; Volume 6, Issue 1 , 2009 , Pages 1-12 ; 15469239 (ISSN) ; Akhavan Niaki, S. T ; Aryaneznad, M. B ; Sharif University of Technology
2009
Abstract
While in multi-periodic inventory control problems the usual assumption are that the orders are placed at the beginning of each period (periodic review) or depending on the inventory level they can happen at any time (continuous review), in this research, we relax these assumptions and assume that the periods between two replenishments of the products are independent and identically distributed random variables. Furthermore, assuming the purchasing price are triangular fuzzy variables, the quantities of the orders are of integer-type and that there are space, budget and service level constraints, incremental discount is considered to purchase products and a combination of back-order and...
Investigation the Effective Factors on Discount Rate of Exchange Traded Funds (ETFs) in Tehran Stock Exchange
, M.Sc. Thesis Sharif University of Technology ; Bahramgiri, Mohsen (Supervisor)
Abstract
Financial markets have been formed to attract and utilize the community’s funds,. In these markets different securities are supplied to meet the needs of a huge variety of investors. they should know the performance and characteristics of these securities, Otherxise they lost in the market. But most investors aren’t familiar with these securities and for this reason almost withdraw from the market. Funds was made up to solve this problem and facilitate the process of entering these investors in financial markets. In funds, professional managers manage portfolio with the capital provided by investors. Exchange Traded Funds (ETFs) are one type of these funds. The stock of ETFs issued in the...
The gardener problem with reservation policy and discount
, Article Computers and Industrial Engineering ; Volume 123 , 2018 , Pages 82-102 ; 03608352 (ISSN) ; Pasandideh, S. H. R ; Akhavan Niaki, S. T ; Nahavandian, M. H ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The Newsboy problem has always been an important issue in inventory management. The multi-product newsboy problem with random yield and budget constraint named as the Gardener Problem is one of the novels and popular extensions of the newsboy problem. Different from the existing studies, this paper presents a multi-product gardener problem with reservation policy. Moreover, a discount rate is offered to those customers who are willing to make reservations. In addition to the demand from the original customers, extra demand is included in the model due to the motivation received by the discount rate. A solution algorithm namely the multi-product gardener problem with reservation policy...
An efficient optimal algorithm for the quantity discount problem in material requirement planning
, Article Computers and Operations Research ; Volume 36, Issue 6 , 2009 , Pages 1780-1788 ; 03050548 (ISSN) ; Shadrokh, S ; Kianfar, F ; Sharif University of Technology
2009
Abstract
An optimal algorithm based on branch-and-bound approach is presented in this paper to determine lot sizes for a single item in material requirement planning environments with deterministic time-phased demand and constant ordering cost with zero lead time, where all-units discounts are available from vendors and backlog is not permitted. On the basis of the proven properties of optimal order policy, a tree-search procedure is presented to construct the sequence of optimal orders. Some useful fathom rules have been proven, which make the algorithm very efficient. To compare the performance of this algorithm with the other existing optimal algorithms, an experimental design with various...
A branch and bound algorithm for the dynamic quantity discount lot size problem with resale
, Article 38th International Conference on Computers and Industrial Engineering 2008, Beijing, 31 October 2008 through 2 November 2008 ; Volume 1 , 2008 , Pages 3-11 ; 9781627486828 (ISBN) ; Shadrokh, S ; Sharif University of Technology
2008
Abstract
This paper presents an optimal algorithm based on Branch and Bound approach for determining lot sizes for purchased component in Material Requirement Planning (MRP) environments with deterministic time-phased demand and constant ordering cost with zero lead time. Backlog is not permitted and the unit purchasing price depends on the quantity of an order and resale of the excess is possible at the ordering time. We assume an all-units discount system with single price break point. Based on proven properties of an optimal order policy, a tree search procedure is designed to construct the sequences of orders and resales amount in optimal order policy. Some useful fathom rules have been proven to...
The Inventory – Routing Problem Considering Discount
, M.Sc. Thesis Sharif University of Technology ; Shavandi, Hassan (Supervisor)
Abstract
In this research, the inventory – routing problem considering discount is studied. The problem consists of a supplier and several retailers who form a network of demand and supply points. In this research, offering discount to retailers is considered as an appropriate policy for reducing total costs of the supply chain. The supplier can augment the utility of her trucks by offering discounts and incentives to the retailers and delivering them amounts of product beyond their economic ordering quantity. This way, the supplier can have full truck-loads instead of lower than full truck-loads while delivering the demands of the retailers. This, can result in a decrease in transportation costs and...
Two metaheuristics to solve a multi-item multiperiod inventory control problem under storage constraint and discounts
, Article International Journal of Advanced Manufacturing Technology ; Volume 69, Issue 5-8 , 2013 , Pages 1671-1684 ; 02683768 (ISSN) ; Niaki, S. T. A ; Mousavi, S. M ; Sharif University of Technology
2013
Abstract
In this paper, a multi-item multiperiod inventory control problem with all-unit and/or incremental quantity discount policies under limited storage capacity is presented. The independent random demand rates of the items in the periods are known and the items are supplied in distinct batch sizes. The cost consists of ordering, holding, and purchasing. The objective is to find the optimal order quantities of all items in different periods such that the total inventory cost is minimized and the constraint is satisfied. A mixed binary integer programming model is first developed to model the problem. Then, a parameter-tuned genetic algorithm (GA) is employed to solve it. Since there is no...
Modeling and solving a bi-objective joint replenishment-location problem under incremental discount: MOHSA and NSGA-II
, Article Operational Research ; 2018 ; 11092858 (ISSN) ; Akhavan Niaki, S. T ; Abdollahi, R ; Sharif University of Technology
Springer Verlag
2018
Abstract
In this paper, the joint replenishment-location problem of some distribution centers (DCs) with a centralized decision maker who is responsible for ordering and dispatching shipments of a single product is modeled. The warehouse spaces of the DCs are limited and the product is sold under an incremental discount policy. The model seeks to minimize the total cost of the supply chain under the joint replenishment policy along with minimizing the cost of locating the DCs in potential sites as the first objective. The second objective is to minimize the warehouse space of all DCs using the revisable approach. As the proposed model is a bi-objective integer non-linear optimization problem...
Three hybrid GAs for discounted fixed charge transportation problems
, Article Cogent Engineering ; Volume 5, Issue 1 , 2018 ; 23311916 (ISSN) ; Hashemi, Z ; Sharif University of Technology
Cogent OA
2018
Abstract
The problem of allocating heterogeneous fleet of vehicles to the existing distribution network for dispensing products fro. manufacturing firm t. set of depots is considered. It is assume. heterogeneous fleet of vehicles with the given capacities and total costs consisting o. discounted fixed cost an. variable cost proportional to the amount shipped is employed for handling products. To minimize the total transportation costs, the problem is modeled i. form of the nonlinear mixed integer program. Due to the NP hard complexity of the mathematical model, three prioritized K-mean clustering hybrid GAs, by incorporating two new heuristic algorithms, are proposed. The efficiency of the algorithms...
Modeling and solving a bi-objective joint replenishment-location problem under incremental discount: MOHSA and NSGA-II
, Article Operational Research ; Volume 20, Issue 4 , 2020 , Pages 2365-2396 ; Akhavan Niaki, S. T ; Abdollahi, R ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2020
Abstract
In this paper, the joint replenishment-location problem of some distribution centers (DCs) with a centralized decision maker who is responsible for ordering and dispatching shipments of a single product is modeled. The warehouse spaces of the DCs are limited and the product is sold under an incremental discount policy. The model seeks to minimize the total cost of the supply chain under the joint replenishment policy along with minimizing the cost of locating the DCs in potential sites as the first objective. The second objective is to minimize the warehouse space of all DCs using the revisable approach. As the proposed model is a bi-objective integer non-linear optimization problem...
The single period problem with price discount and probabilistic initial inventory
, Article 2006 IIE Annual Conference and Exposition, Orlando, FL, 20 May 2006 through 24 May 2006 ; 2006 ; Haji, M ; Sharif University of Technology
2006
Abstract
In this paper we consider a newsvendor problem in which the suppliers offer quantity discounts. We assume that the initial inventory at the beginning of the period is a random variable. This assumption, among other applications, may apply to the case where the decision about the order quantity must be made at a time long before the start of the period and the available inventory may decrease due to several factors, such as deterioration, consumption, etc. up to the start of the period. In this paper, we obtain the optimal order quantity that maximizes the total profit for this model
A Weibull distributed deteriorating inventory model with all-unit discount, advance payment and variable demand via different variants of PSO
, Article International Journal of Logistics Systems and Management ; Volume 40, Issue 2 , 2021 , Pages 145-170 ; 17427967 (ISSN) ; Banerjee, T ; Shaikh, A. A ; Akhavan Niaki, S. T ; Bhunia, A. K ; Sharif University of Technology
Inderscience Publishers
2021
Abstract
The goal of this research is to formulate an inventory control problem of a single item with variable demand dependent on displayed stock level and selling price of the commodity. The item deteriorates based on a three-parameter Weibull distribution and advance payment is needed to purchase the item with the all-unit discount policy. Shortages are allowed partially and backlogged with the rate dependent on the length of customers' waiting time. The corresponding problem is formulated as a profit maximisation model. For solving this problem, four different variants of particle swarm optimisation (PSO) are utilised. Then, the application of the model is illustrated with the help of a numerical...
A hybrid polynomial-time algorithm for the dynamic quantity discount lot size model with resale
, Article Computers and Operations Research ; Volume 39, Issue 7 , 2012 , Pages 1771-1778 ; 03050548 (ISSN) ; Eshghi, K ; Sharif University of Technology
Abstract
We propose an efficient optimal algorithm for determining the lot sizes for purchase component in Material Requirement Planning (MRP) environments with deterministic time-phased demand and zero lead time. In this model, backlog is not permitted, the unit purchasing price is based on the all-units discount system with single price break point and resale of the excess units is acceptable at the ordering time. The problem is divided into the sub-plans with specific properties by the dynamic programming (DP) method already presented. By modifying the main structure of the DP method, we present a branch-and-bound algorithm to obtain the optimal ordering policy for each sub-plans. Furthermore, we...
Project Procurement Scheduling, Considering Incremental Discount Model
, M.Sc. Thesis Sharif University of Technology ; Shadrokh, Shahram (Supervisor)
Abstract
Project Scheduling is one of the most important branches of the operational research and management science and scheduling the project activities is considered to be one of the branches of project scheduling issue. Different goals are considered in project scheduling, but financial goals are one of the most necessary criterions in this research area.This study investigates the matter of project procurement scheduling considering incremental discount model and also storehouse space limitation with the aim of minimizing the costs of ordering, maintaining and purchasing materials required for the project.Project procurement scheduling issue, restrictions included, is an NP¬hard issue....
Project Procurement Scheduling Problem With Gradual Ordering and All-Unit Discount under The Presence of Multiple Suppliers
, M.Sc. Thesis Sharif University of Technology ; Shadrokh, Shahram (Supervisor)
Abstract
Simultaneous planning of project scheduling and material procurement can improve the project execution costs. Hence, the issue considering this approach that each activities requirement can be distributed on the duration of it, has been addressed here by a mixed-integer programming model (named model 2). The proposed model facilitates the procurement decisions by accounting for a number of suppliers offering a distinctive discount formula from which to purchase the required materials. This paper proposed a genetic algorithm combining with a heuristic method to deal with the problem. The underlying factors of the solution methods are calibrated by the Taguchi method to obtain robust...
A stochastic aggregate production planning model in a green supply chain: Considering flexible lead times, nonlinear purchase and shortage cost functions
, Article European Journal of Operational Research ; Volume 230, Issue 1 , 2013 , Pages 26-41 ; 03772217 (ISSN) ; Baboli, A ; Sazvar, Z ; Sharif University of Technology
2013
Abstract
In this paper we develop a stochastic programming approach to solve a multi-period multi-product multi-site aggregate production planning problem in a green supply chain for a medium-term planning horizon under the assumption of demand uncertainty. The proposed model has the following features: (i) the majority of supply chain cost parameters are considered; (ii) quantity discounts to encourage the producer to order more from the suppliers in one period, instead of splitting the order into periodical small quantities, are considered; (iii) the interrelationship between lead time and transportation cost is considered, as well as that between lead time and greenhouse gas emission level; (iv)...
A parameter-tuned genetic algorithm for the resource investment problem with discounted cash flows and generalized precedence relations
, Article Computers and Operations Research ; Volume 36, Issue 11 , 2009 , Pages 2994-3001 ; 03050548 (ISSN) ; Akhavan Niaki, T ; Shahsavar, M ; Sharif University of Technology
2009
Abstract
A resource investment problem with discounted cash flows (RIPDCF) is a project-scheduling problem in which (a) the availability levels of the resources are considered decision variables and (b) the goal is to find a schedule such that the net present value of the project cash flows optimizes. In this paper, the RIPDCF in which the activities are subject to generalized precedence relations is first modeled. Then, a genetic algorithm (GA) is proposed to solve this model. In addition, design of experiments and response surface methodology are employed to both tune the GA parameters and to evaluate the performance of the proposed method in 240 test problems. The results of the performance...
Oligopolistic contracting: Channel coordination under competition
, Article Naval Research Logistics ; Volume 66, Issue 8 , 2019 , Pages 619-631 ; 0894069X (ISSN) ; Talebian, M ; Sharif University of Technology
John Wiley and Sons Inc
2019
Abstract
We study contracts between a single retailer and multiple suppliers of two substitutable products, where suppliers have fixed capacities and present the retailer cost contracts for their supplies. After observing the contracts, the retailer decides how much capacity to purchase from each supplier, to maximize profits from the purchased capacity from the suppliers plus his possessed inventory (endowment). This is modeled as a noncooperative, nonzero-sum game, where suppliers, or principals, move simultaneously as leaders and the retailer, the common agent, is the sole follower. We are interested in the form of the contracts in equilibrium, their effect on the total supply chain profit, and...