• Journal of the Korean Society for Heat Treatment
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• v.5 no.3
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• pp.149-156
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• 1992

Transformation behavior and reversible shape memory effct of Ti-Ni-Cu alloys with various Cu content has been investigated by means of electrical resistivity measurement, differential scanning calorimetry. X-ray diffraction and strain gage sensor. The transformation sequence in Ti-Ni-Cu alloys substituted by Cu for Ni up to 5at.% occurs to $B2{\leftrightarrow}B19^{\prime}$ and it proceeds in two stages by addition of 10 at.%Cu. i.e. $B2{\leftrightarrow}B19{\leftrightarrow}B19^{\prime}$. But the content of Cu increases up to 20at.%, it has been transformed in one stage ; $B2{\leftrightarrow}B19$. The shape change of Ti-40Ni-10Cu alloy which was constrain aged in circular form bended in $B2{\leftrightarrow}B19$ transformation but it spreaded out in $B19{\leftrightarrow}B19^{\prime}$ transformation. The amount of reversible shape change (${\Delta}{\varepsilon}$) of Ti-47Ni-3Cu alloy constrain aged at $400^{\circ}C$ after solution treatment has a maximum value of about $5.6{\times}10^{-3}$, but that of cold rolled and constrain aged specimens exhibits a little value independent of Cu concentrations.

• Korean Journal of Metals and Materials
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• v.46 no.12
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• pp.780-787
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• 2008

For the advanced high strength steels (AHSS), high-manganese TWIP (twinning induced plasticity) steels exhibit high tensile strength (800-1000 MPa) and high elongation (50-60%). However, the TWIP steels need to be understood of delayed fracture following the cup drawing test. Among the factors to cause delayed fracture, i.e, martensite transformation, hydrogen embrittlement and residual stress, the effects of martensite transformation (${\gamma}{\rightarrow}{\varepsilon}$ or ${\gamma}{\rightarrow}{\alpha}^{\prime}$) were investigated on the delayed fracture phenomenon. Microstructural phase analysis was conducted for cold rolled (20, 60, 80% reduction ratio) steels and tensile deformed (20, 40, 60% strain) steels. For the Al-added TWIP steels, no martensite phase was found in the cold rolled and tensile deformed specimen. But, the TWIP steels with no Al addition indicated the martensite transformation. The cup drawing specimens showed the martensite transformation irrespective of the Al-addition to the TWIP steel. However, the TWIP steel with no Al exhibited the larger amount of martensite than the case of the TWIP steel with Al addition. For the reason, it was possible to conclude that the Al addition suppressed the martensite transformation in TWIP steels, therefore preventing the delayed fracture effectively. However, it was interesting to note that the mechanism of delayed fracture should be incorporated with hydrogen embrittlement and/or residual stress as well as the martensite transformation.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.6 no.2
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• pp.1-8
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• 2002

Let $T_{\phi}$ be a generalized Gauss transformation and $[a_1,\;a_2,\;{\cdots}]_{T_{\phi}}$ be a symbolic representation of $x{\in}[0,\;1)$ induced by $T_{\phi}$, i.e., generalized continued fraction expansion induced by $T_{\phi}$. It is shown that the distribution of relative frequency of [$k_1,\;{\cdots},\;k_n$] in $[a_1,\;a_2,\;{\cdots}]_{T_p}$ satisfies Central Limit Theorem where $k_i{\in}{\mathbb{N}}$ for $1{\leq}i{\leq}n$.

• Korean Journal of Microbiology
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• v.27 no.2
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• pp.162-167
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• 1989

Western blot analysis of lysates of Streptococcus pneumoniae revealed a single polypeptide species that cross-reacted with E. coli RecA antiserum. The apparent molecular weight of this putative RecA protein analog (RecAsp) was 24, 000 smaller than any other known RecA analogue. The RecAsp protein was present at the same level in competent and non-competent cells.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.2
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• pp.309-314
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• 1987

Using computer picture processing, a method of extracting the region of a car number plate is described. A modified Hough transformation, in which parameter plane is restricted, is proposed. The demerits of Hough transformation, i.e., it requires much computation time and storage capacity, are reduced by this method. Further, taking the features of a car number plate into consideration, the region of a car number plate is extracted.

• Communications of the Korean Mathematical Society
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• v.29 no.4
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• pp.519-526
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• 2014

A large number of summation and transformation formulas involving (generalized) hypergeometric functions have been developed by many authors. Here we aim at establishing two (presumably) new general hypergeometric transformations. The results are derived by manipulating the involved series in an elementary way with the aid of certain hypergeometric summation theorems obtained earlier by Rakha and Rathie. Relevant connections of certain special cases of our main results with several known identities are also pointed out.

• The Journal of Society for e-Business Studies
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• v.6 no.2
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• pp.1-12
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• 2001

AS EC is expanded and activated, many message standards, EDI, XML, UDF, etc are defined and is used at various business part. But the existed translator supports only one mapping translation, for example, EDI-to-UDF, UDF-to-EDI. So many user must be introduced a new translation when new business(message standard) is beginning, To solve this problem, we propose XConverter System as registering mapping information which is able to transform to user requested format using same translator even though it is transferred any formatted message in this paper. Also, We design and implement this system which is capable to integrate with existed legacy system, including DB transformation functionality. The .XConverter System supports changing the business message format to the common user used message format. And this system easily migrates with existed legacy system because DB transform module is component. Therefore, The proposed System is more various and flexible than the other translation system that provide just one mapping transformation.

• Journal of the Korean Ceramic Society
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• v.25 no.3
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• pp.277-283
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• 1988

Extremely fine $TiO_2$ powders were synthesized from titanium chloride by the precipitation and freeze drying method. The phase transformation and electrical conductivity were investigated as a function of temperature. X-ray analysis showed that the phase transformation of the synthesized powder from the anatase to rutile occured at 64$0^{\circ}C$ and finished at 92$0^{\circ}C$ due to small particle size and large specific surface area. The activation energy obtained from electrical conductivity vs. temperature was about 1.63eV. This relatively large value was due to porosity in the specimen.

• Bulletin of the Korean Mathematical Society
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• v.49 no.3
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• pp.621-633
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• 2012

By establishing a new summation formula for the series $_3F_2(\frac{1}{2})$, recently Rathie and Pogany have obtained an interesting result known as Kummer type II transformation for the generalized hypergeometric function $_2F_2$. Here we aim at deriving their result by using a very elementary method and presenting two elegant results for certain terminating series $_3F_2(2)$. Furthermore two interesting applications of our new results are demonstrated.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.149-154
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• 2001

현재 어느 기업이든 업무 환경을 e-Transformation하는 쪽에 많은 노력을 기울이고 있으며 이의 성과는 곧 기업의 경쟁력 제고와 밀접한 관계에 있다. 이러한 환경의 변화는 건설산업에 있어서도 예외일 수 없으며 오히려 국내외 현장에서 Business가 이루어지는 건설산업에서는 더욱 업무환경을 e-Transformation화하는 것이 필요한 상태이다. 그러나 많은 기업들의 노력에도 불구하고 If의 실제적 가시효과는 크지 않은 것이 현실이며 Best Practice도 국내외의으로 많지 않고 이에 따라 건설업에서의 17 활용 수준은 매우 미미한 상태이다. 국내외에 널리 알려진 ERP Package도 국내의 건설 업무 Process에 최적으로 적용할 수 있는 Solution은 없어 많은 기업에서 IT 적용의 방향 수립을 제대로 못하고 있는 상황이다: LG건설은 이러한 건설환경에서 IT를 활용하여 모든 업무를 공사과 손익이 연결된 사업관리를 이루고 언제 어디서든지 IT를 활용한 업무를 수행할 수 있도록 하는 통합정보시스템을 구축, 운영 중에 있으며 현재 많은 성과를 거두고 있다. 또한 핵심 기술에 대하여는 정보화 사업 전략하에 건설업계에서는 드물게 정보화 사업도 추진 중에 있으며 이러한 성공사례를 공유하고자 한다.