Multiproduct Economic Lot Scheduling Problem with Returns and Sorting Line

This work studies a hybrid manufacturing–remanufacturing system with a sorting line and disposal. In particular, it models a company that collects used product, remanufactures returned products that have been evaluated as suitable to be recovered, and manufactures new products to satisfy customer demand. Specifically, the system is modeled as a multilevel inventory system, with three types of stock (used products inventory, recoverable inventory, and serviceable inventory), each characterized by an inventory holding cost, and three limited capacity resources: a sorting line, which enables the company to distinguish those returns that are remanufacturable from those that are not; a remanufacturing line to carry out operations on sorted remanufacturable returns; and a manufacturing line to produce new products in order to satisfy customer demand. Each resource is characterized by a setup cost, as well as a constant production rate, while each type of stock is associated with an inventory holding cost. The aim of the paper is to develop a model for the considered production system in order to minimize the setup and inventory holding costs. In particular, the objective is to evaluate the behavior of a controllable disposal rate with the minimization of the total cost function, by considering the effect on the remanufacturing and manufacturing lines.

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The Study of MTO Online Manufacturers' Guaranteed Delivery Time Model with Order Batching

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.933.824 ◽

2014 ◽

Vol 933 ◽

pp. 824-829

Author(s):

Qiang Gang Zhu ◽

Lei Liu ◽

Yun Sheng Wang

Keyword(s):

Lead Time ◽

Delivery Time ◽

Lot Size ◽

Setup Cost ◽

Time Model ◽

Holding Cost ◽

Inventory Holding Cost ◽

Inventory Holding ◽

Cost Of Transportation ◽

Marketing Approach

To MTO on-line manufacturers, one of the most popular time-based competitive strategies is to widely advertise a uniform delivery time guarantee to all the customers. While providing time guarantee can be an effective marketing approach, it is critical for firms to reduce lead time to keep the promise. Decreasing lot size in batching is one of the most important levers to compress lead time in operation. This research expands existing blanket delivery-time guarantee models by integrating operation approach and marketing approach. The online manufacturers guaranteed delivery time model with order batching is established. Some analytic results are provided, and numerical examples are conducted to provide further insight into the problem. The effects of batch processing setup cost, unit inventory holding cost and unit compression cost of transportation time are analyzed. The results indicate that when batch processing setup cost decrease, unit inventory holding cost or unit compression cost of transportation time increase, the online manufacturer should decrease the lot size and shorten the guaranteed delivery time. The customers time and price sensitivities have adverse influences on the manufacturers delivery time decision.

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Optimization of Inventory Holding Cost Due to Price, Weight, and Volume of Items

Journal of Risk and Financial Management ◽

10.3390/jrfm14020065 ◽

2021 ◽

Vol 14 (2) ◽

pp. 65

Author(s):

Amulya Gurtu

Keyword(s):

Physical Nature ◽

Quantity Discounts ◽

Actual Cost ◽

Inventory Policies ◽

Average Percentage ◽

Holding Costs ◽

Holding Cost ◽

Inventory Holding Cost ◽

Retail Organizations ◽

Inventory Holding

The inventory carrying cost has been assumed uniform for all products in an organization or a warehouse. This assumption is not valid for a diversified range of items in an organization or warehouse. This paper tested this hypothesis of variations in inventory holding costs in a warehouse in two industries based on the physical nature and the price of products. It is found that organizations with a wide variety of products need to calculate the inventory holding cost for each item (SKU) rather than using an average percentage cost of inventory. Inventory holding costs of items in two different organizations were calculated based on the various factors, including the actual cost of space due to the voluminous nature of the items with their existing inventory policies. A variation in inventory holding costs for each item was observed. The variation was small for an organization with homogeneous input costs, and it was large for a multi-product organization. The overall savings in the inventory holding cost due to adjusting the inventory policies through this methodology was found to be about 3%, which is significant for a big organization. This analysis will affect the decision the determining inventory carrying cost, inventory policies (e.g., stocking levels), and pricing policies (e.g., quantity discounts) for retail organizations.

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The Inventory Routing Problem with Demand Moves

SN Operations Research Forum ◽

10.1007/s43069-020-00042-z ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Annelieke C. Baller ◽

Said Dabia ◽

Guy Desaulniers ◽

Wout E. H. Dullaert

Keyword(s):

Urban Areas ◽

Research Literature ◽

Inventory Routing ◽

Routing Problem ◽

Inventory Routing Problem ◽

Solution Approach ◽

Holding Cost ◽

Inventory Holding Cost ◽

Problem Instances ◽

Inventory Holding

AbstractIn the Inventory Routing Problem, customer demand is satisfied from inventory which is replenished with capacitated vehicles. The objective is to minimize total routing and inventory holding cost over a time horizon. If the customers are located relatively close to each other, one has the opportunity to satisfy the demand of a customer by inventory stored at another nearby customer. In the optimization of the customer replenishments, this option can be included to lower total costs. This is for example the case for ATMs in urban areas where an ATM-user that wants to withdraw money could be redirected to another ATM. To the best of our knowledge, the possibility of redirecting end-users is new to the operations research literature and has not been implemented, but is being considered, in the industry. We formulate the Inventory Routing Problem with Demand Moves in which demand of a customer can (partially) be satisfied by the inventory of a nearby customer at a service cost depending on the quantity and the distance. We propose a branch-price-and-cut solution approach which is evaluated on problem instances from the literature. Cost improvements over the classical IRP of up to 10% are observed with average savings around 3%.

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