• Journal of the Korean Society for Precision Engineering
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• v.24 no.11
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• pp.91-100
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• 2007

Many manufacturing devices must execute motions as quickly as possible to achieve profitable high-volume production. Most of them have devices having flexibility and a time delay of one sampling is added to the plants when they are controlled by fast discrete controllers, which brings about non-minimum phase zeros. This paper develops a control strategy that combines feedforward and feedback control with command shaping for such devices. First, the feedback controller is designed to increase damping and eliminate steady-state error. Next, the feedforward controller is designed to speed up the transient response. Finally, an appropriate reference profile is generated using command-shaping techniques to ensure fast point-to-point motions with minimum residual vibration. The particular focus of the paper is to understand the interactions between these individual control components. The resulting control strategy is demonstrated on a model of a high-speed semiconductor manufacturing machine.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.57
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• pp.93-102
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• 2000

The objective of this paper is to introduce to development of resource planning system of footwear manufacturing. The system development is to be done separately by module and each of which makes interface possible. And the final goal of the system development is to combine those modules to be ERP system covering all works from order to make, shipment, accounting. First, in this case study, introduce analysis of existing business flow and design of standard business process for development of systems. Second, describe in and out of the standard business process for shoes production and information management. Third, basic structure and design of the total system flow, configuration of completed 6 sub-systems of developing total 13 sub-system are presented. Fourth, function of software modules and principal algorithm and basic data structuring techniques o the 6 sub-systems are explained. Finally, hereafter implementation and development plans are presented.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.10a
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• pp.97-100
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• 2000

Today deep drawing and ironing are the major process in manufacturing of battery case used in cellular phone from aluminum. The same technology is utilized in manufacturing of steel or aluminum cans for components of medical instrument, portable PC, walkman and so on. Most of these processes require multi-stage ironing following the deep drawing and redrawing processes. The practical aspects of this technology are well known and gained through extensive experiment and production know-how. However, the fundamental aspects of theses processes are relatively less known. Thus, it is expected that process simulations using FEM techniques would provide additional detailed information that could be utilized to improve the process condition. This paper illustrates the application of process modeling to deep drawing and redrawing operations for High Precision Rectangular Battery Case. A commercially avaliable finite element code LS-DYNA3D was used to simulate deep drawing and redrawing operations.

• The Journal of Information Systems
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• v.20 no.3
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• pp.1-24
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• 2011

Recently, six sigma has been widely adopted in a variety of industries as a disciplined, data-driven problem solving approach or methodology supported by a handful of powerful statistical tools in order to reduce variation through continuous process improvement. Also, data mining has been widely used to discover unknown knowledge from a large volume of data using various modeling techniques such as neural network, decision tree, regression analysis, etc. This paper proposes a six sigma methodology based on data mining for effectively and efficiently processing massive data in driving six sigma projects. The proposed methodology is applied in the hot stove system which is a major energy-consuming process in a "P" steel company for improvement of heat efficiency through reduction of energy consumption. The results show optimal operation conditions and reduction of the hot stove energy cost by 15%.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.303-306
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• 2001

To shorten the delivery time for new products, a lot of prototype plastic parts manufacturing technologies have been developed including injection molding, vacuum casting, thermal forming and so on. Among them, RIM is becoming one of a important soft tooling methods to produce prototype and mass production parts within short time. Further more, as the rapid prototyping technology based tooling methods are playing an important role in prototype manufacturing industry, the utility of the RIM is increasing. But few analyses and mold design techniques have been developed so far due to its chemical and mechanical complexity during the packing and curing process. This research suggests mold gate design criteria to prevent bobbles from molded parts through simplified mathematical model and change of bubble sizes according to the geometry of the molded parts through experiments. Also this study shows the differences of bobble generation mechanism between RIM and injection molding.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1123-1126
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• 2005

For creation of low temperature polycrystallinesilicon (LTPS) the line beam excimer laser annealing (ELA) is a well known and established technique in mass production. With introduction of Sequential Lateral Solidification (SLS) some aspects such as crystalline quality, throughput and flexibility regarding the substrate size could be improved, but for OLED manufacturing still further process development is necessary. This paper discusses line beam ELA and SLS techniques that might enable process engineers to make polycrystalline-silicon (poly-Si) films with a high degree of uniformity and quality as required for system on glass (SOG) and active matrix organic light emitting displays (AMOLED). Equipment requirements are discussed and compared to previous standards. SEM images of process examples are shown in order to demonstrate the viability.

• Progress in Superconductivity and Cryogenics
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• v.5 no.2
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• pp.30-35
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• 2003

The inductive superconducting fault current limiter (SFCLJ limits the fault current with its dc reactor. To fabricate the optimal dc reactor for inductive SFCL, several design and manufacturing technologies are necessary. In this paper, the manufacturing technology for dc reactor and cryogenic cooling method are described in detail. GM-cryocooler was used enlarge the critical current of dc reactor by cooling down the temperature of dc reactor about 20 K. Moreover, the results of short circuit test were described. Finally, the thermal characteristics of conduction-cooled system were discussed and then, sub-cooled nitrogen system was proposed to enhance the thermal stability of dc reactor.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.3
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• pp.13-19
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• 2003

The high speed machining technology has been improved remarkably in die/mold industry with the growth of parts and materials industries. Though the spindle speed of machine tool increases, the condition monitoring techniques of the machine tool, tool and workpiece in high speed machining ate incomplete. In tins study, efficient sensing technology in high speed machining is suggested by observing the characteristics of cutting force, gap sensor and accelerometer signal also, machinability of high-speed machining is experimentally evaluated sensing technique to monitor the machine tool and machining conditions was performed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.4
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• pp.1-7
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• 2010

Recently optical and electric and electronic forms in the field of ultra fine patterns has been used extensively, and techniques of the optical parts are required that can precision-machine this micro-patterns such as V or R-shaped micro-groove patterns. In this study, V and R type, shaping the way micro groove brass machining process to characterize the material feed rate and cutting depth and the V and R as a variable brother, using two kinds of diamond tools for each picture shape and surface roughness caused by conditions such as chips, processed through the analysis of effects of geometry and analysis such as precision machining.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.1
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• pp.83-90
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• 2002

As high-precision parts are needed with manufacturing techniques improved. the demand of high-precision machine tools has been increasing They are made to developed the precision measuring skill to maintenance the accuracy of themselves as a matter or course We one paper measured straightness and orthogonality of the square to verify that it is possible for CT(circular test) method by 2-dimensional probe and the square to measure orthogonality Furthemore we compared the result of the study with the computer simulation's to prove its possibility and made an improvement of measuring method.