This study examines an imperfect production and inspection system with customer return and defective disposal. We develop an optimal lot sizing model with production and inspection quality investment, incorporating all the quality costs. We find the optimal lot size, rework frequency, defective proportion, and Type I and Type II inspection error proportions which minimize the total quality cost...

Rework continues to affect both cost and schedule performance throughout the construction industry. The direct costs alone often tally to 5% of the total construction costs. Using the data obtained from 359 construction projects in the Construction Industry Institute database, this paper assesses the impacts of rework on construction cost performance for projects in various categories. In addit...

This paper presents a test, diagnosis, and rework analysis model for use in manufacturing process modeling. The approach includes a model of functional test operations characterized by fault coverage, false positives, and defects introduced in test, in addition to rework and diagnosis (diagnostic test) operations that have variable success rates and their own defect introduction mechanisms. The...

Efficiency in the supply chain can be established by integrating supplier-retailer inventory policy. This article proposes integrated model between under stochastic demand. aims to determine optimal review period and calculate total cost, including some defective items, backorder price discounts, losing flexibility costs. We assume that retailer order 'n' times for every 'm' shipment from suppl...

In manufacturing systems, defective items are produced for machine drift and error. Usually, an imperfect production rate is random, if the not reworked, these considered trash harm environment. The proposed model aims to reduce waste by reworking products maximizing profit. For profit maximization or overall cost minimization of system, setup has significant. A discrete investment each phase i...

Citra Karya Metal is a mould maker and injection service for industries that produce plastic products such as brackets washing machines. Defective in the bracket's production are serious problems since number large. The existence of this defective product quite challenging company terms time cost. Products do not comply with standards will be reworked by flushing them from excessive or destroyi...

Economic production quantity (EPQ) inventory model for trended demand has been analyzed with rework facility and stochastic preventive machine time. Due to the complexity of the model, search method is proposed to determine the best optimal solution. A numerical example and sensitivity analysis are carried out to validate the proposed model. From the sensitivity analysis, it is observed that th...

Mistakes create rework. Rework takes time and increases costs. The traditional software engineering methodology defines the ratio of Design:Code:Test as 40:20:40. As we can easily see that 40% time and efforts are used in testing phase in traditional approach, that means we have to perform rework again if we found some bugs in testing phase. This rework is being performed after Design and code ...

This study uses mathematical modeling to examine a multi-product economic manufacturing quantity (EMQ) model with an enhanced end items issuing policy and rework failures. We assume that a multi-product EMQ model randomly generates nonconforming items. All of the defective are reworked, but a certain portion fails and becomes scraps. When rework process ends and the entire lot of each product i...