• JSTS:Journal of Semiconductor Technology and Science
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• v.11 no.1
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• pp.1-5
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• 2011

To enter next process control, numerous approaches, including run-to-run (R2R) process control and fault detection and classification (FDC) have been suggested in semiconductor manufacturing industry as a facilitation of advanced process control. This paper introduces a novel type of optical plasma process monitoring system, called plasma eyes chromatic system (PECSTM) and presents its potential for the purpose of fault detection. Qualitatively comparison of optically acquired signal levels vs. process parameter modifications are successfully demonstrated, and we expect that PECSTM signal can be a useful indication of onset of process change in real-time for advanced process control (APC).

• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.2
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• pp.1-10
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• 2002

Process capability indices are widely used in industries and quality assurance system. In past years, process capability analysis have been used to characterize process performance on the basis of univariate quality characteristics. However, in actual manufacturing industrial, statistical process control (SPC) often entails characterizing or assessing processes or products based on more than one engineering specification or quality characteristic. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index $MC_{pm}^+$ using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.36
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• pp.275-285
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• 1995

In recent years there has been increasing interest in the issue of process centering in manufacturing process, The traditional process capability indices Cp, Cpk and Cpu are used to provide measure of process performance, but these indices do not represent the issue of process centering. A new measure of the process capability index Cpm is proposed that takes into account the proximity to the target value as well as the process variation when assessing process performance. However, Cpm only considers acceptance cost for deviation from target value within specification limits, do not includes economic consideration for rejected items. This paper proposes flexible process performance measures that considered quadratic loss function caused by quality deviation within specification limits, rejection cost associated with the disposition of rejected items, and inspection cost. In this model disposition of rejected items are considered under perfect corrective procedures and the absence of perfect corrective procedures.

• Transactions on Electrical and Electronic Materials
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• v.13 no.3
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• pp.129-135
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• 2012

A number of surface mount technology (SMT) process variables including land design are considered for minimizing tombstone defect in flexible printed circuit assembly in high volume manufacturing. As SMT chip components have been reduced over the past years with their weights in milligrams, the torque that once helped self-centering of chips, gears to tombstone defects. In this paper, we have investigated the correlation of the assembly process variables with respect to the tombstone defect by employing statistically designed experiment. After the statistical analysis is performed, we have setup hypotheses for the root causes of tombstone defect and derived main effects and interactions of the process parameters affecting the hypothesis. Based on the designed experiments, statistical analysis was performed to investigate significant process variable for the purpose of process control in flexible printed circuit manufacturing area. Finally, we provide beneficial suggestions for find-pitch PCB design, screen printing process, chip-mounting process, and reflow process to minimize the tombstone defects.

• Journal of Information Processing Systems
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• v.14 no.3
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• pp.607-620
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• 2018

The problem surrounding methods of implementing the software testing process has come under the spotlight in recent times. However, as compliance with the software testing process does not necessarily bring with it immediate economic benefits, IT companies need to pursue more aggressive efforts to improve the process, and the software industry needs to makes every effort to improve the software testing process by evaluating the Test Maturity Model integration (TMMi). Furthermore, as the software test process is only at the initial level, high-quality software cannot be guaranteed. This paper applies TMMi model to Automobile control software testing process, including test policy and strategy, test planning, test monitoring and control, test design and execution, and test environment goal. The results suggest improvement of the automobile control software testing process based on Test maturity model. As a result, this study suggest IT organization's test process improve method.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.9
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• pp.95-102
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• 2004

A flexible incremental roll forming process has been developed by adopting the advantages of the incremental forming process and the roll forming process: i.e., inherent flexibility of the incremental forming process and continuous bending deformation of the roll forming process. It has an adjustable roll set as a forming tool composed of one upper center roll and two pairs of lower support rolls, which plays a key role during forming process. Through the experiments based on the various combinations of process parameters, it is shown that the incremental roll forming process is so effective as to manufacture various doubly curved sheet metals including concave-convex combination shapes in which there exists a line of inflection. The proposed relationship of the experimental parameters and the radius of curvature of the formed sheet boundary is found to be useful in prediction and control of the final shape.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.11
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• pp.98-105
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• 1999

As the IC(Integrated Circuit) has been densified and complicated, it is required to thorough process control to improve yield. Experts, for this purpose, focused on the process analysis automation, which is came from the strict data management in semiconductor manufacturing. In this paper, we presents the process analysis system that can analyze causes, for a output after processes. Also, the plasma etching process that highly affects yield among semiconductor process is modeled to predict a output before the process. To approach this problem, we use adaptively trained neural networks that exhibit superior accuracy over statistical techniques. And in comparison with methods in other paper, a method that history of trend for input data is considered is shown to offer advantage in both learning and prediction capability. This research regards CD(Critical Dimension) that is considerable in high integrated circuit as output variable of the prediction model.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.76.4-76
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• 2001

ESR(ElectroSlag Remelting) Process is secondary fine process and melts steels by electric resistance heat and fines the melting steels by an approproate solidification process. The final products are determined through the velocity of melting and the course of solidification in the process that is achieved by way of proper course of solidification. Thus, it is very important to monitor and control the process parameters which affects the melting and solidification process to get the high quality products. This paper describes a method to derive the mathematical model and analysis the dynamic characteristics for designing a controller of the ESR processes. The process consists of a melting and solidifying process and electrical system include the contact resistance mechanism ...

• Journal of the Korean Society of Industry Convergence
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• v.22 no.2
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• pp.235-241
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• 2019

The shoe manufacturing process is very low compared to other industries due to the labor-intensive process. As automation and smart factories are becoming more and more automated, changes in the shoe manufacturing process are also needed. In this paper, we want to standardize the fuse manufacturing process by modularizing it. First, we defined the terms of shoeupper and fuse process, the shoe upper fuse process by function and classified it as a modular process. The fuse process can be modularized with pattern supply module, pattern recognition module, pattern laminate module, pattern waiting module, adhesion module, heat pressing module, transmission module, etc.

• Knowledge Management Research
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• v.20 no.3
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• pp.107-117
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• 2019

Successful start-ups are driven by opportunities, teams, and the resources needed to grow the business. Systematic business process management is required to maximize the efficiency of business operations. However, the existing entrepreneurial process research has limitations that it is difficult to intuitively and dynamically provide the necessary information for start-up operation, and it is necessary to define necessary information (resources, stakeholders, activities). In this study, we suggest the "Start-up Process Repository System" which overcomes limitations of existing entrepreneurial process research. The architecture for the Start-up Process Repository System provides five layers and enables each layer to interact four interfaces between each layer. This study improves start-ups' accessibility to the start-up business process repository created from the existing repository architecture and increases the utility derived from it by providing methodologies for components that offer useful start-up knowledge.