• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.298-301
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• 2001

In semiconductor manufacturing, wafer fabrication is the most complicated and important process, which is composed of several hundreds of process steps and several hundreds of machines involved. The productivity of the manufacturing mainly depends on how well they control balance of WIP flow to achieve maximal throughput under short manufacturing cycle time. In this paper mathematical formulation is suggested for the stepper scheduling, in which cycle time reduction and maximal production is achieved.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.97.4-97
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• 2001

Recently, TFT LCD (thin film transistor liquid crystal display) manufacturing industry is more concerned with the ways of cleaning large TFT LCD´s with high pixed density than ever Ultrasonic cleaners with high frequencies like 1MHz (megasonic cleaners) are effective in removing very small particles without causing mechanical damage to the surface. In this study a megasonic cleaner for TFT LCD manufacturing process is developed and the performance is evaluated through experiments. The experimental results show that the developed magasonic cleaners is effective in removing very small particle from the LCD panel.

• Korean Management Science Review
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• v.10 no.2
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• pp.111-120
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• 1993

The most important factors for a product to survive in the market are cost and quality. In recent years, quality proceeds to cost. There are many techniques of use to improve the quality of a product. One of the techniques is applying statistical methods (especially Taguchi method) to real operational conditions for a continuous manufacturing process in P company. There are 91 factors to control in the process. So, we predetermined 7 main effect factors and 6 interactive effect factors by statistical methods and advices of engineers. With these 13 factors, we determined the optimal level of operations for the process.

• Journal of Environmental Science International
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• v.21 no.7
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• pp.883-890
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• 2012

Emission characteristics of gaseous odor compounds emitted from the charcoal manufacturing process were investigated, and evaluated the odor removal efficiency of odor control devices. It was found that the measured odor dilution ratio of emission gases ranged from 10,000 to 44,814, which exceed largely the emission standard in the stack. Methylmercaptan, trimethylamine, hydrogen sulfide, acetaldehyde were turned out as major odor compounds of the charcoal manufacturing process. It was revealed that the odor removal ratio of odor control devices were very low due to the its improper maintenance and wrong design.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.2
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• pp.6-11
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• 2010

For the purpose of reducing the energy consumption in the house heating, the various devices have been developed. One of these is to control the flow in the heat pipe and the flow control valve using shape memory alloy(SMA) spring is proposed in our study. The proposed house heating system is to save the gas consumption and the remote control system is designed for the convenience of using the proposed valve. The developed valve consists of SMA spring, disk, return spring, and regulation handle. The regulation handle is for supplying the additional hot water and is controlled by remote-control-motor. In order to design the remote control system, the Zigbee wireless communication protocol is used. The performance of the proposed valve structure is shown through the experimental result.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.94-98
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• 2012

Butterfly valves are usually used by the plumbing systems in plant engineering field. Valves are used for controlling the flow rate and pressure of fluid. In order to control the flow rate using butterfly valve, the position control of valve disc should be designed. However, since there are lots of uncertain disturbance in plumbing system, the robust control system should be considered. Therefore, the sliding mode control system using neural network algorithm is proposed in this paper. The proposed control system provides the estimating method using neural network for the unmeasurable disturbance in the plumbing system. The performance of the proposed control system is evaluated through computer simulations.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.5
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• pp.13-19
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• 2011

In this paper, the active monitoring and control system is developed. This system can monitor the status of high the speed spindle in real time during its processing, and can analyze its influence of dimensional accuracy and processing if any, and can control the machining condition to realize the machining system equipped with active monitoring and self-diagnostic features. Machining experiment was performed on 3 materials Al, Brass and S45C in order to derive the relation between active monitoring and control algorithm by the machining load. In addition, we measured surface roughness of processing specimen along with the data change of spindle rotating speed and conveying speed according to variation of machining load. Based on these experiments, we derived relations for each material that can be applied to the control algorithm to allow self control of the rotating speed and conveying speed according to the machining load.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.6
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• pp.39-45
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• 2011

Due to the introduction of the electronic control systems, agricultural machine is getting complicated with its special function. The complex electronics system increases difficulty of maintenances in the wiring harness system. The heavy wiring harness has some poor reliability and workability in the production line of manufacture also. So, in this study, some small local control modules are developed to complement the difficulties with the benefits of distributed control system. All of the local control modules are connected by using CAN communication. This system developed this study has the advantages of modification or alteration of wiring and local modules. All the sensors and actuators can be easily monitored and controlled by the main controller with the appropriate communication protocol made by in this study.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.4
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• pp.31-38
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• 2022

In this study, we designed and manufactured an intelligent gripper-control device to safely grip unknown objects. The gripper control device consists of a DSP circuit, power supply circuit, communication circuit, and amplifier circuit diagrams. The DSP is used because the values of the 3-axis force sensor to which the gripper is attached are measured and calculated at high speeds. The gripping force is determined based on this value, and the object must be safely gripped with the determined value. A basic characteristic test of the control device of the manufactured intelligent gripper was conducted, and it was confirmed that it operated safely.

• Transactions of Materials Processing
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• v.15 no.1 s.82
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• pp.82-88
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• 2006

In this paper, the web-based monitoring system is developed for the effective process monitoring of mold manufacturing using web. In developed system, the cutting force for monitoring the manufacturing condition is measured using hall-sensor that is low cost and useful to be installed in a machine tool indirectly. Specially, the current of main spindle in a machine tool is converted into cutting force by various experiments. For effective web-based monitoring, the program which runs in the local computer of client is made to exchange message between a server and a client by making of ActiveX control and the result of manufacturing is shown on web-browser by Ch language. The developed system in this study is the foundation of establishing E-manufacturing in mold factory.