• Proceedings of the KWS Conference
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• 2004.05a
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• pp.156-158
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• 2004

The microstructural evolution in a 304 stainless steel weld during FSW was examined. The SZ and TMAZ showed typical dynamically recrystallized and recovered microstructures, respectively, The microstructural observation revealed that sigma phase was formed at the advancing side of the stir zone. A possibility was suggested that the rapid formation of the sigma phase is related to the transformation of austenite to delta-ferrite in the stir zone, from introduction of high strain and dynamic recrystallization during FSW.

• Proceedings of the IEEK Conference
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• 2002.06e
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• pp.47-50
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• 2002

An extended-counting analog to digital converter (ADC) is designed to have a high resolution(14bit) with low power consumption and small dia area. First order sigma-delta modulator with a simple counter for incremental operation eliminates the need of big decimation filter in conventional sigma-delta type ADC. To improve the accuracy and linearity, extended mode of successive approximation is followed. For 14-bit conversion operation, total 263 clocks(1 clock for reset, 256 clocks for incremental operation and extended 6 clocks for successive approximation operation) are needed with the sampling rate of 10 Ms/s This ADC is implemented in a 0.6um standard CMOS technology with a die area of 1 mm ${\times}$ 0.75 mm.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.4
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• pp.263-271
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• 2000

To investigate the distribution of air pollutants dispersion in the horizontal wind fields, a chaff release experiment was carried out by an airplane. The temporal and spatial variations of a chaff plume from an elevated point source using the WSR-88D(NEXRAD) radar. The observed profiles of radar reflectivity were compared with the Gaussian diffusion model at slightly unstable atmospheric condition. The present study shows that the distributions of radar reflectivity from chaffs and their concentration by the model are in general agreement with time variation. The dispersion coefficients in downwind($\sigma$(sub)x) and crosswind($\sigma$(sub)y) spread data exceeded what has generally been found at Pasquill and Brigg\`s estimates. As a result, it was clearly shown that horizontal and vertical diffusion coefficients are more accurately determined as compared with theoretical coefficients. At longer diffusion distances(than 10km), a radar observation provided the determination of maximum range and diffusion height more qualitatively, too.

• BMB Reports
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• v.31 no.6
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• pp.607-610
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• 1998

Transcription of mitochondrial DNA in the yeast S. cerevisiae depends on recognition of a consensus nonanucleotide promoter sequence by mitochondrial RNA polymerase specificity factor, which is a 43 kDa polypeptide encoded by the nuclear MTF1 gene. Mtf1p has only limited amino acid sequence homology to bacterial sigma factors, but functions in many ways like sigma in that it is required for promoter recognition and initiation of transcription. To analyze the corebinding region of Mtf1p, monoclonal antibodies to this protein were prepared. Recombinant Mtf1p overproduced in E. coli was purified to near homogeneity and used to raise monoclonal antibodies (mAbs). From fused cells screened for Mtf1p mAbs by immunodot blot analysis, 19 positive clones were initially isolated. Further analysis of positive clones by Western blotting resulted in 4 mAbs of Mtf1p.

• Communications of the Korean Mathematical Society
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• v.9 no.3
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• pp.731-737
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• 1994

Let $(\Omega, F, P)$ be a probability space with F a $\sigma$-algebra of subsets of the measure space $\Omega$ and P a probability measures on $\Omega$. Suppose $a > 0$ and let $(F_t)_{t \in [0,a]}$ be an increasing family of sub-$\sigma$- algebras of F. If $r > 0$, let $J = [-r, 0]$ and $C(J, R^n)$ the Banach space of all continuous paths $\gamma : J \to R^n$ with the sup-norm $\Vert \gamma \Vert_C = sup_{s \in J} $\mid$\gamma(x)$\mid$$ where $$\mid$\cdot$\mid$$ denotes the Euclidean norm on $R^n$. Let E and F be separable real Banach spaces and L(E,F) be the Banach space of all continuous linear maps $T : E \to F$ with the norm $\Vert T \Vert = sup {$\mid$T(x)$\mid$_F : x \in E, $\mid$x$\mid$_E \leq 1}$.

• Proceedings of the Korean Society for Quality Management Conference
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• 2004.04a
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• pp.229-238
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• 2004

많은 기업들이 급변하는 기업 환경과 고객의 요구 변화에서 생존과 지속적인 성장을 하기 위하여 신제품을 개발하고 있다. 하지만 신제품 개발을 하는데 있어 대부분의 기업들이 신제품 개발 프로세스의 후반부인 신제품 생산이나 프로토타이핑에 관심을 집중하고 있다. 이는 신제품 개발 프로젝트의 성공률을 낮추는 주요 원인으로 차후에 기술적인 문제 및 고객의 니즈의 부적합과 같은 문제를 일으키게 된다. 그래서 기업들은 과거 신제품 개발 프로세스의 문제점을 개선하기 위해 점차 신제품 개발 프로세스의 전반부인 상품기획 단계에 보다 관심을 갖게 되었다. 따라서 본 논문에서는 나날이 증대되고 있는 신제품 개발 프로세스의 전반부인 상품기획의 중요성에 대해 살펴보고, 이를 위하여 마케팅 단계에서 6시그마 품질 수준을 달성할 수 있는 MFSS (Marketing For Six Sigma)방법과 MFSS의 적용을 통해 과거의 신제품 개발 프로세스를 보다 효율적으로 개선하여 새로운 신제품 개발 프로세스인 MFSS Model를 제시하고자 한다.

• Journal of Korean Society for Quality Management
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• v.38 no.3
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• pp.449-462
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• 2010

In this Paper, We analyzed influence Factor to TPM Performance in medium and small enterprises by empirically. By Literature survey, We hypothesize education training and 5S influence to individual improvement, independence maintenance, planning and foresight, which also influence to flexibility, total equipment performance, quality, which finally influence to lower cost, delivery date. To analyze empirically, we survey questionnaire in medium and small enterprises being below 300 people. From statistical analysis, 7 hypotheses are rejected, which is different existing research. This is analyzed that reflect actuality that medium and small enterprises is different from large enterprises. We expect that result of this treatise does concentration effort in important factor to get TPM performance in medium and small enterprises.

• Journal of Korean Society for Quality Management
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• v.40 no.2
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• pp.106-116
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• 2012

This paper aims to develop the adequate quality cost model at a company which delivers ICT(information communication technology) services. One particular business unit was in the first instance selected and quality costs were then analysed at an organization level, for a department and for specific processes. Some areas were determined for quality improvement at each level and their causes were also investigated. However, the existing PAF(prevention, appraisal and failure) models reveled some limitations because the ICT services company included the different number of large and complicated business processes. The PAF model did not sufficiently highlight the detailed causes of failure costs. It did not also stimulate the relevant department's strong responsibility to improve such problems. Both micro PAF and process cost models were proposed in order to cope with this. In final, it explains the relationship between six sigma and quality costing, suggesting how to use the quality costing results as a means of promoting either continuous improvement or innovation in a case company.

• Journal of the Korean Statistical Society
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• v.9 no.1
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• pp.31-38
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• 1980

The problem considered in this paper can be defiened as follows. Consider observations $x_1, x_2, \cdot, x_n$ which are assumed to come from a mixed population of the density function, $$f(x) = \sum^m_{k=1} pkf_k(x)$$ where m is the number of subpoulations and $p_k$ is the proportion of subpopulation k such that $\sum^m_{k=1} pk=1, 0

• Journal of the Korean Ceramic Society
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• v.31 no.3
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• pp.241-248
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• 1994

The ionic conductivity in glassy systems were calculated as functions of temperature and ion concentration using Monte-Carol method considering interaction between neighbouring ion-site occupancies, {{{{ rho }}'s. Also the vacancy availability factor, V, the effective jump frequency factor, W, and the charge correlation factor, fc, have been investigated. The Arrhenius plot could be obtained from the ln {{{{ sigma }}T vs. 1/T* plots and was in exellent agreement with the experimental observations. The effects of the various types of potential well on the ionic conductivity have been considered. The activation energy Eg for ion motion in the glass was 1.3│ε│from the ln {{{{ sigma }}T vs. 1/T* plots.