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This paper proposes a capacity planning system CPS to determine the capacity of machines and kits in integrated circuit final test plants. CPS applies the concept of workload levelling and infinite capacity planning on dual resources. CPS consists of four modules: Work-in-Process WIP-Pulling Module WPM, Lot Release Module LRM, Workload Accumulation Module WAM and Workload Balance Module WBM. The WPM pulls WIP from the end of the process route to meet the master production schedule MPS. If WIP cannot meet the MPS requirement, LRM is executed. WAM simultaneously accumulates the workload to conduct an IC final test machine and kit on a daily basis. WBM levels the loading of machines and kits by adjusting the lot starting time with the use of these resources. CPS is developed in Microsoft Visual Basic, and industrial data are used to test its performance. The experimental design includes four factors: workload balance heuristics, MPS variation, MPS variation frequency and product mix. The simulation results are analysed by using descriptive statistics and ANOVA. The results show that CPS is effective and efficient in balancing the workload of resources, including machines and kits.

This study illustrates the application of lean management and Radio Frequency Identification (RFID) technology to improve the logistics efficiency in a distribution center. The distribution center stores more than ten million parts belonging to about ten thousand types. There are more than ten thousand storage and retrieval operations for hundreds of part types on a daily basis. Value stream mapping was used to draw current state mapping with material flow, information flow, and time flow. Based on the concept of business process reengineering, future state mapping with RFID application was developed. Preliminary experiments showed that 100% read rate was achieved with a fixed RFID reader and an antenna installed at a garage door and Ultra-High Frequency passive tags mounted on each pallet. The benefit using RFID in the distribution center is analyzed (e.g., with a saving of cycle time and process time by 24% and 22%, respectively) and promoted.

This research proposed Advanced Planning and Scheduling (APS) system to effectively and efficiently balance machine loading for color filter fabrication plants in Thin Film Transistor - Liquid Crystal Display industry. APS uses six modules to estimate future equipment loading and calculate order due dates according to capacity limits by taking into account the due date and size of orders, as well as the capacity, loading, and yield of fabrication plants. These six modules include: Order Priority Module, WIP-Pulling Module, Order Release Module, Material Management Module, Workload Accumulation Module, and Workload Balance Module. A lot’s start processing time at each production step is selected leading to the best workload balance. Simulation and experimental design are used to evaluate the performance of APS. Production manager can use APS to improve color filter fabrication plants’ productivity and competitiveness.

Integrated Circuit (IC) manufacturing consists of four major phases - wafer fabrication, wafer probe, IC packaging, and final test. Wafer fabrication and wafer probe belong to front-end process, while IC packaging and final test belong to backend process. In this research, integrated capacity planning system (ICPS) is proposed for IC backend manufacturing by taking into account the capacity and capability of resources. This study develops integrated infinite capacity planning integrating the capacity planning of both IC packaging and final test processes to minimize the standard deviations of machine utilization and kit utilization as well as the total extra capacity requirement (as a percentage) exceeding the capacity limit of machine and kit. ICPS applies the concept of workload leveling and infinite capacity planning on dual resources. ICPS consists of five modules: Work-In-Process (WIP) Pulling Module, Lot Release Module, Resource Selection Module, Workload Accumulation Module, and Workload Balance Module. WIP-Pulling Module pulls WIP from the end of the process route to meet the master production schedule (MPS). If WIP cannot meet the MPS requirement, Lot Release Module is executed. ICPS will use Resource Selection Module to accumulate the required resource capacity along its routine at different time buckets. Workload Accumulation Module simultaneously accumulates the workload of the major resources. Workload Balance Module levels the loading of resources by adjusting the lot’s start time using these resources. ICPS is developed in Microsoft Visual Basic and industrial data are used to test its performance. The results show that ICPS is effective and efficient to balance the workload of resources for IC backend factories including packaging and final test.

An infinite capacity planning system (ICPS) considering the capacity and capability of machines as well as the capacity of jigs is developed for an integrated circuit packaging plant. ICPS consists of five modules: work-in-process (WIP) pulling module, lot release module, resource selection module, workload accumulation module, and workload balance module. The WIP-pulling module pulls WIP from the end of the process route to meet the master production schedule (MPS). If WIP cannot meet the MPS requirement, the lot release module is executed to release new lots. The resource selection module helps a lot to select an appropriate resource, by taking into account the resource's capacity and capability, at each operation step and calculate the lot's planned start time and planned finished time at each step. The workload accumulation module accumulates the workload of each machine and each jig on each day. The workload balance module balances the loading of machines and jigs by adjusting the lot's start time us...

Facility planning is crucial to the performance of array fabs in Thin Film Transistor - Liquid Crystal Display (TFT-LCD) industry. In order to avoid costly changes and modifications of fab layouts at the installation or production stages, the designers should carefully evaluate design alternatives and then select the best one during the design stage. A TFT-LCD manufacturing process consists of four basic processes: array, color filter, cell, and module. This research proposes an Array Fab Design Procedure (AFDP) to conduct quick calculations to develop and evaluate initial design alternatives for TFT-LCD array fabs. A series of practical formulae are presented to sequentially determine the related design parameters. The proposed AFDP provides a basis for rapid modeling and evaluation of array fab designs. AFDP is developed in Microsoft Visual Basic and data from real array fabs are used to demonstrate its effectiveness and efficiency. Results indicate that AFDP can quickly calculate the related fab design parameters. “Job shop with small bays” leads to the least average sheet moving distance. With AFDP as a tool, fab designers can evaluate design alternatives and conduct what-if analysis in the initial phase of fab design.

Resource-constrained multi-project scheduling problems (RCMPSP) consider precedence relationship among activities and the capacity constraints of multiple resources for multiple projects. RCMPSP are NP-hard due to these practical constraints indicating an exponential calculation time to reach optimal solution. In order to improve the speed and the performance of problem solving, heuristic approaches are widely applied to solve RCMPSP. This research proposes Hybrid Genetic Algorithm (HGA) and heuristic approach to solve RCMPSP with an objective to minimize the total tardiness. HGA is compared with three typical heuristics for RCMPSP: Maximum Total Work Content, Earliest Due Date, and Minimum Slack. Two typical RCMPSP from literature are used as a test bed for performance evaluation. The results demonstrate that HGA outperforms the three heuristic methods in term of the total tardiness.

An infinite capacity planning system (ICPS) is developed for an integrated circuit packaging plant. ICPS consists of five modules: Work-In-Process (WIP) Pulling Module, Lot Release Module, Resource Selection Module, Workload Accumulation Module, and Workload Balance Module. WIP-Pulling Module pulls WIP from the end of the process route to meet the master production schedule (MPS). If WIP cannot meet the MPS requirement, Lot Release Module is executed to release new lots. Resource Selection Module facilitates a lot to select an appropriate resource at each operation step and calculate the lot's planned start time and planned finished time at each step. Workload Accumulation Module accumulates the workload of each machine and each jig on each day. Workload Balance Module balances the loading of machines and jigs by adjusting the lot's start time using these resources. Simulation is used to evaluate ICPS performance, and results show that ICPS can effectively and efficiently balance the workload of production resources.

The garment manufacturing is a traditional and fashion industry, that is globally competitive and customer centric. The most critical operation process is sewing, as it generally involves a great number of operations. The aim of assembly line balancing planning in sewing lines is to assign task to the workstation in order that the machines of the workstation can perform the assigned tasks with a balanced loading. Assembly line balancing problem (ALBP) is known as an NP-hard problem. Thus, the heuristic methodology could be a better way to plan the sewing lines in a reasonable time. This paper presents a grouping genetic algorithm (GGA) for assembly line balancing problem of sewing lines in garment industry. GGA was first developed by Falkenauer in 1992 as a type of GA which exploits the special structure of grouping problem, and overcomes the drawbacks of GA. GGA allocates workload among machines as evenly as possible, so the minimum mean absolute deviations (MAD) can be minimized. The performance is verified through solving two real problems in garment industry. The computational results reveal that GGA outperforms GA in both simple and complex problems by 13.81% and 8.81%, respectively. This shows GGA's effectiveness in solving ALBP.

This research develops interaction models among companies in IC supply chain to study the information integration among them. The main processes of IC supply chain are IC design, wafer fabrication, wafer probe, IC packaging/ assembly, and final test. A workflow model between IC design houses and wafer fabrication plants is developed with focuses on purchase order, engineering data, and work-in-process status. This model facilitates the standardization and simplification for the information integration interfaces, which could increase the communication efficiency and effectiveness between customers and vendors. Finally, Extricity Alliance software is used in a case study to demonstrate the interaction process and information flow between IC design houses and wafer fabrication plants.

This research proposed lot release policies for color filter fabs based on iterative simulation. Heuristic lot release plan was first developed and used as the input of an AutoMod simulation model to generate the expected performance that was used to improve the release plan and then iteratively simulated.

This research proposes an Order Assignment Policy (OAP) to effectively and efficiently assign orders to color filter fabs. The objectives of this research is to minimize order tardiness and minimize the variance of fab utilization by taking into account fabs ' available capacity and orders ' due date, batch size, product type, and process routing. OAP consists of three modules: Order Priority Module (OPM), WIP-Pulling Module (WPM), and Order Release Module (ORM). OPM assigns different priorities to orders according different dispatching rules. WPM pulls WIP from the end of the process route to meet the orders in Master Production Schedule (MPS). If WIP cannot meet the MPS requirement, ORM is executed to select one of the fabs and release lots into this fab. An AutoMod simulation model is developed, and data of real color filter fabs are collected and used to evaluate OAP's performance based on the design of experiments. Preliminary simulation results show that the combination of OPM using Earliest Due Date (EDD) and ORM using Least Fab Utilization (LFU) leads to the least average lateness of orders, while OPM using Largest Batch Size (LBS) and ORM using LFU results in the least variance of fab utilization.