This paper studies a single-stage production system, two-stage production system where specification limits are designed for inspection. When quality characteristics fall below a lower threshold or above an upper threshold, a decision is made to rework or scrap the item. The target is to determine the optimum target for a process based on rework or scrap costs. In contrast to previous studies, ...

At Skyworks Solutions throughput of the back side through-wafer via etch process was low because of a high rework rate. The high rework rate was due to an organic residue blocking the etch. A process was first developed to remove the residue and then integrated into the via etch process. The optimized via etch process resulted in a reduction in reworks and a significant increase in process thro...

In pipe spool assemblies used in construction, pre-fabrication errors inevitably occur due to the complexity of the tasks involved in the pipe spool fabrication process, the inaccuracy of the tools employed for performing these tasks, human error, and inadequate inspection and monitoring during the process. Permanent deflections may also occur during shipment and transportation. After delivery ...

Fast-tracking through activity overlapping allows for shortening the total project duration at the expense of an increased likelihood of rework. Activity overlapping allows downstream successor construction activities to start with incomplete information from their upstream predecessor design activities. The nature of information evolution and the strength of dependency between these activities...

We study a production-inventory system with multiple unreliable supply sources. Through inspection and rework the system can improve the quality of the units received from the supply sources. There are two interleaved decisions: the replenishment quantities from the sources and the inspection-rework quantities among the units received. We show the optimal solution to the replenishment decision ...

In this paper, two economic production quantity (EPQ) models are proposed for deteriorating/imperfect items with rework process. The production process is imperfect, and imperfect quality items are reworked to become serviceable. At the same time, the remaining good quality items may deteriorate. The inspection of deteriorated items is also imperfect, so that deteriorated items may be sold to c...

Rework cycle is at the heart of modeling projects, one of the major application areas of system dynamics. In this paper we introduce a new formulation for rework cycle in which multiple defects may exist in a task. We compare the performance of this model with three other formulations, two adopted from system dynamics literature and one agent-based formulation. This comparative study illustrate...

in this paper, absorbing markov chain models are developed to determine the optimum process mean levels for both a single-stage and a serial two-stage production system in which items are inspected for conformity with their specification limits. when the value of the quality characteristic of an item falls below a lower limit, the item is scrapped. if it falls above an upper limit, the item is ...

Quality is a critical attribute of software. A software process with sophisticated design and analysis would benefit the quality of the output software greatly. To enhance the quality of a software process, some quality assurance activities need to be incorporated into the process. As a consequence, the quantity of rework activities as well as the cost and duration of the process would be incre...