• Journal of the korean Society of Automotive Engineers
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• v.4 no.1
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• pp.1-4
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• 1982

우리가 흔히 쓰는 관리도에도 X over bar-R관리도, P(또는 Pn)관리도, C(또는 U)관리도가관리 도의 대종을 이루고 있다. 그러나 기계공업 특히 자동차공업분야에서는 기계가공 부품을 일일이 재기가 어렵거나 시간이 걸리므로 고-노고우 게이지(go-no go gauge)를 써서 선별하는 경우가 많다. 또 금형베품의 조립시에는 측정개소가 많기 때문에 어느 한 부분만을 제어서 관리할 수 없으므로 여러곳을 제어서 관리해야 하는데 이때 금형전체를 어떻게 맞출것인가, 혹은 제품의 공차관리를 어떻게 해나갈 것인가 하는 문제가 생긴다. 다음에 이러한 경우에 유용하게 쓰일 수 있는 관리도의 예를 소개하고자 한다.

• Journal of Korean Society for Quality Management
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• v.24 no.2
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• pp.172-178
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• 1996

In this study, we developed a software for statistical process control. This software presents $\bar{x}$, R, CUSUM, EWMA control chart and process capability index. In this system, statistical process control methods are integrated into the automated method on a real time base. It is available in process control of specified type and can be performed on personal computer with network system.

• 대한예방의학회:학술대회논문집
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• 2000.10a
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• pp.110-111
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• 2000

• Bulletin of the Korean Mathematical Society
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• v.49 no.1
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• pp.57-61
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• 2012

It is well known that one could use a fixed loxodromic or parabolic element of a non-elementary group $G{\subset}M(\bar{\mathbb{R}}^n)$ as a test map to test the discreteness of G. In this paper, we show that a test map need not be in G. We also construct an example to show that the similar result using an elliptic element as a test map does not hold.

• Proceedings of the Korean Reliability Society Conference
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• 2005.06a
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• pp.147-155
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• 2005

When a failure or fault is detected, the product is adjusted or design change and is returned to its original condition before the failure or fault. Continuous improvement of the FMEA system is to determine an optimum product reliability that minimizes the total cost per unit time associated with inspection, repair, and the nondetection cost.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.722-727
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• 2016

In this study, we attempted to reduce the generation of waste acids in the electropolishing process by improving the current efficiency. The optimum conditions of the electropolishing process when using the round bus bar were determined by the Taguchi method. The current density, polishing time, electrolyte temperature and flow rate were selected as the control factors for the current efficiency in the electropolishing process. An orthogonal array was created by considering three levels for each factor and experiments were carried out. The larger-the-better SN ratios were calculated by the Taguchi method. The current density was the most important factor affecting the current efficiency and the polishing time was the least important one. The optimum conditions to minimize the generation of waste acids were a current density of $45A/dm^2$, polishing time of 4 min, electrolyte temperature of $65^{\circ}C$ and flow rate of 7 L/min. The results of the ANOVA confirmed that the effects of the current density, electrolyte temperature and flow rate are significant at the 95% confidence level. The increase in the contact area and contact force afforded by using the round bus bar improved the current efficiency which, in turn, reduced the amount of waste acids generated. Further research is planned to investigate the effect of the type of bus bar on the current efficiency.

• Journal of the Korea Concrete Institute
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• v.25 no.2
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• pp.155-163
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• 2013

This study investigated the bond characteristics of embedded deformed steel bar in donut type biaxial hollow slabs. The donut type hollow sphere make concrete inner cover formed between steel bar and hollow sphere due to the hollow shape and arrangement. Generally, inner cover was thinner than outer cover, and some part of donut type biaxial hollow slab has smaller inner cover thickness than $2.5d_b$. It was affected to the bond condition of deformed bar. Furthermore, inner cover thickness changes along the longitudinal deformed bar due to hollow shape. Therefore, donut type hollow slab was divided 3 regions according to the hollow shape such as insufficient region, transition region, sufficient region. Pull-out test were performed to find out the effect of bond condition by the region. Main parameters are inner cover thickness, embedded length and bond location. Bond characteristics of donut type biaxial hollow slab were confirmed through comparison of bond stress-slip relationship, maximum bond strength and bond stress distribution of each regions. And the calculation method of bond strength of donut type biaxial hollow slab was suggested based on the test results.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.157-166
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• 1981

Laboratory experiements were conducted to evaluate water uptake and osmotic potential of soybean seeds associated with germinability. Bonus, Wayne, Essex and Pickett were selected for this study. Large and small seeds from the four varieties were included in water uptake measurements at $25^{\circ}C$ There were significant differences in water uptake during germination due to seed size and cultivars at optimum moisture condition, -6 and -15 bars soil moisture. As water stress increased, the water uptake of Pickett and Essex were superior to Bonus and Wayne, and small seeds were superior to large seeds. The seed moisture content at germination was 60.8% on a fresh weight basis under optimum moisture condition. The minimum moisture contents necessary for the germination were 50.2% at -6 bars and 50.9% at -15 bars. There were significant differences among varieties in seed osmotic potential during germination, although these differences depended on imbibition time. The average osmotic potential ranged from -32.0 bars after 4 hours imbibition to -11.2 bars at the beginning of germination. The correlation coefficient between seedling length and osmotic potential was not significant after any period of imbibition, suggesting that osmotic potential is not directly associated with seedling growth. However, osmotic potential is closely related to water uptake capacity of soybean seed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.16 no.1
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• pp.43-52
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• 2003

The present study is to investigate the ultimate behavior and limit state design of 2-I) R/C structures, with the changing of crack direction, and the yielding of the reinforcing steel bars, and Is to introduce an algorithm for the limit state design and analysis of 2-D R/C structures, directly from the finite element model. For the design of reinforcement in concrete the limit state design equation is incorporated into finite element algorithm to be based on the pointwise elemental ultimate behavior. It is also introduced a simplified nonlinear analysis algorithm for stress-strain relationship of R/C plane stress problem considering the cracking and its rotation in concrete and the yielding of the reinforcing steel bar. The algorithm is incorporated into the nonlinear finite element analysis. The analysis model is compared with the experimental model of R/C shear wall. In a simple design example for a shear wall, the required reinforcement ratios in each finite element is obtained from the limit state design equations.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.4
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• pp.97-103
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• 2017

The objective of this study is to develop and commercialize an on-board fuel storage system for CNG vehicles. A type 4 vessel is made of resin-impregnated continuous filament windings on a polyamide (PA6) liner. In particular, this study localized the PA6 liner's fabrication and development. To analyze the filament winding, a specimen test was performed, and the results were verified values obtained using finite element analysis. In this study, the filament winding and fibers were optimized for a 207 bar composite cylinder in a compressed natural gas vehicle.