• Plant Resources
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• 제6권2호
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• pp.108-113
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• 2003

This study was carried out to obtain basic information for possibility of oral vaccine in carrot using Agrobacteruim -mediated transformation system. The epitope region of porcine epidemic diarrhea virus (PEDV) spike gene which is classified as a member of the Coronaviridae and causes an acute enteritis in pigs was successfully expressed in carrot (Daucus carota) using the Agrobacterium-mediated transformation system. Hypocotyl segments of in vitro germinated plantlets were infected with Agrobacteriun tumefaciens LBA 4404 harboring PEDV spike gene. Embryogenic callus (EC) was induced on MS selection medium with 1 mg/L 2,4-D, 50 mg/L kanamycin and 300 mg/L cefotaxime after 45 days of culture. Subcultured ECs on MS selection medium without 2,4-D were converted to somatic embryos (SE) of various stage; globular, heart and torpedo stage. Putative transgenic embryos were selected on MS medium with 50 mg/L kanamycin and 300 mg/L cefotaxime. Regenerated plantlets from transformed SE were induced on MS medium containing 50 mg/L kanamycin after 30 days of culture. Genomic PCR confirmed the integration of PEDV spike gene into nuclear genome of carrot and northern blot analysis demonstrated the expression of PEDV spike gene in transgenic carrot.

• 열처리공학회지
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• 제27권1호
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• pp.15-22
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• 2014

This study is to investigate the phase changes and cold workability after isothermal transformation at $780^{\circ}C$ by using the high temperature gas nitrided (HTGN) STS 430 ferritic stainless steel specimens. The phase diagram of STS 430 steel obtained by calculation showed that the phase appeared at $1100^{\circ}C$ showed as ${\alpha}+{\gamma}{\rightarrow}{\gamma}{\rightarrow}{\gamma}+Cr_2N{\rightarrow}{\gamma}+Cr_2N+CrN$ with increasing nitrogen concentration. Also, the transformation of ${\gamma}{\rightarrow}Cr_2N$ during heat treatment isothermally at $780^{\circ}C$, nitrogen pearlite with lamellar type was fully formed at the nitrogen permated surface layer for 10 hrs. However, this transformation was not completed for 1 hr, resulting nitrogen pearlite plus martensite. The cold rolled specimen of isothermally transformed at $780^{\circ}C$ for 10 hrs after high temperature gas nitriding decreased the layer thickness of nitrogen pearlite inducing the deformation of hard $Cr_2N$ phase. the dissolution rate of $Cr_2N$ phase increased rapidly with increasing cold rolling ratio. Specimens with the microstructure of nitrogen pearlite (isothermally transformed at $780^{\circ}C$ for 10 hrs) were possible to cold rolling without crack formation. However, the mixed structures of nitrogen pearlite + martensite (isothermally transformed at $780^{\circ}C$ for 1 hr) were impossible to cold deformation without cracking.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.75-80
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• 2001

The purpose of this study is to investigate the characteristics of springback for various process conditions of the 2D draw-bending operation. The process variables are the forming temperature, the geometry of tools such as punch profile radius(Rp) and die profile radius(Rd). Especially, in order to control the springback, the use of the warm forming method is applied. For the warm draw-bending, five steps of temperature ranges, from room temperature to $200^{\circ}C$, were adopted. And two kinds of steel sheets, namely SCP1 and TRIP(transformation-induced plasticity), the newly developed high strength Steel, were adopted. As a result, the springback was affected by the elevated temperature and the geometry of tools in two kinds of steel sheets.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.355-355
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• 2006

In this study, we have applied principal component analysis-based 2D (PCA2D) correlation spectroscopy to the temperature-dependent IR spectra of biodegradable poly(hydroxyalkanoate). PCA2D analysis reveals clearly that there are two components in crystalline band of C=O stretching mode without being hampered by noise. To better understand the thermal behavior of biodegradable poly(hydroxyalkanoate), eigenvalue manipulating transformation (EMT) technique was also employed. By uniformly lowering the power of a set of eigenvalues associated with the original data, the subtle contributions from minor eigenvectors are highlighted. Details of thermal behavior of biodegradable poly(hydroxyalkanoate) studied by PCA2D correlation spectroscopy with EMT will be discussed.

• 한국작물학회지
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• 제49권3호
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• pp.232-236
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• 2004

오차드그래스의 최적 조직배양조건을 확립하기 위하여 'Roughrider' 품종의 성숙종자로부터 최적 배발생 캘러스 유도 및 식물체 재분화에 미치는 배지첨가물질의 영향을 조사하였다. 성숙종자로부터 배발생 캘러스 유도시 첨가되는 생장조절 물질로는 3 mg/L 2,4-D가 가장 효율적이었으며, 식물체 재분화에는 1 mg/L 2,4-D와 3 mg/L BA가 첨가된 배지에 캘러스를 배양했을 때 36.3%의 재분화율을 나타내었다. 캘러스 유도배지와 재분화배지에 1 g/L의 casein hydrolysate와 300 mg/L의 proline을 동시에 첨가해주었을 때 캘러스 유도율과 재분화율이 각각 57.3%와 60.7%로 증가되었다. 또한 항산화물질로서 10 mg/L의 $\textrm{AgNO}_3$ 와 40 mg/L의 cysteine을 첨가해준 과 켈러스 유도율 재분화율 각각 68.7%와 71.7%까지 증가되었다. 본 연구를 통하여 확립된 성숙종자로부터 효율적인 배발생 캘러스의 유도 및 식물체 재분화 체계는 유전자 형질전환을 통한 신품종 오차드그래스 개발에 유용하게 응용되어질 수 있을 것이다.

• 한국환경성돌연변이발암원학회지
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• 제24권1호
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• pp.1-9
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• 2004

Three D-type cyelins (D1, D2, and D3) are expressed in G1 phase of the cell cyele and have been implicated in cell transformation and neoplasia in human and mouse. Cyclin D1 overexpression or amplification was described in various human cancers. However, there is controversy about the role of cyclin D2 in cell cyele progression and human carcinogenesis. Specially, loss of cyelin D2 is involved in a vital tumor suppressor function in normal breast tissue, and that its loss may be related to tumorigenesis. The author examined to effect over-expression of cyclin D2 on the cell proliferation, apoptosis, and cell cycle using cyclin D2 transfected stable T47D breast cancer cells to investigate whether cyclinD2 functions as a positive regulator or negative regulator in cell proliferation. Overexpression of cyclin D2 led to the suppression of cell growth in cyclin D2 transfected T47D in both in its expression level and a time dependent manner with up to 50% reduction of cell growth at 72 hours. Therefore, the authors performed the cell cycle phase analysis using the flow cytometry to investigate the effect of cyclin D2 on the cell cycle phase in cyclin D2 transfected stable T47D cells. The flow cytometry analysis revealed increased sub G0 phase in cyclin D2 transfeted cells up to 23% at 72 hours. To confirm these results induced by overexpression of cyclinD2, the apoptotic bodies were counted in control and cyclin D2 transfected T47 cells. There are markedly increases of apoptotic bodies in cyclin D2-transfected cells up to 18%. These results suggested that Cyclin D2 suppresses the cell proliferation in breast cancers cells via the induction of apotosis.

• Journal of Electrical Engineering and Technology
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• 제8권5호
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• pp.1188-1193
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• 2013

In content based image retrieval (CBIR) system, the images are represented based upon its feature such as color, texture, shape, and spatial relationship etc. In this paper, we propose a MRI Image Retrieval using wavelet transform with mahalanobis distance measurement. Wavelet transformation can also be easily extended to 2-D (image) or 3-D (volume) data by successively applying 1-D transformation on different dimensions. The proposed algorithm has tested using wavelet transform and performance analysis have done with HH and $H^*$ elimination methods. The retrieval image is the relevance between a query image and any database image, the relevance similarity is ranked according to the closest similar measures computed by the mahalanobis distance measurement. An adaptive similarity synthesis approach based on a linear combination of individual feature level similarities are analyzed and presented in this paper. The feature weights are calculated by considering both the precision and recall rate of the top retrieved relevant images as predicted by our enhanced technique. Hence, to produce effective results the weights are dynamically updated for robust searching process. The experimental results show that the proposed algorithm is easily identifies target object and reduces the influence of background in the image and thus improves the performance of MRI image retrieval.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2000년도 추계학술대회 논문집
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• pp.33-36
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• 2000

The dynamic recrystallization (DRX) of medium carbon steels (SCM 440 and POSMA45) was studied with torsion test in the temperature range of $900-1100^{\circ}C$ and the strain rate range of $5.0x10^{-2}\;-\;5.0x10^0/sec$. To establish the quantitative equations for DRX, the evolution of flow stress curve with strain was analyzed. The critical strain (${\varepsilon}_c$) and strain for maximum softening rate ( ${\varepsilon}^{*}$) could be confirmed by the analysis of work hardening rate ($d{\sigma}/d{\varepsilon}\;=\; \theta$). The volume fraction of dynamic recrystallization ($X_{DRX}$) as a function of processing variables, such as strain rate ( $\dot{\varepsilon}$ ), temperature (T), and strain ( $\varepsilon$ ) were established using the ${\varepsilon}_c$ and ${\varepsilon}^{*}$. For the exact prediction, the ${\varepsilon}_c$, ${\varepsilon}^{*}$ and Avrami' exponent (m') were quantitatively expressed by dimensionless parameter, Z/A respectively. The transformation-effective strain-temperature curve for DRX could be composed. It was found that the calculated results were agreed with the experimental data for the steels at any deformation conditions.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.800-811
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• 2014

Recent developments in the prediction of the contribution of windnoise to the interior SPL have opened a realm of new possibilities in terms of i) how the convective and acoustic sources terms can be identified, ii) how the interaction between the source terms and the side glass can be described and finally iii) how the transfer path from the sources to the interior of the vehicle can be modelled. This work discusses in details these three aspects of wind noise simulation and recommends appropriate methods to deliver required results at the right time based on i) simulation and experimental data availability, ii) design stage at which a decision must be made and iii) time available to deliver these results. Several simulation methods are used to represent the physical phenomena involved such as CFD, FEM, BEM, FE/SEA Coupled and SEA. Furthermore, a 1D and 2D wavenumber transformation is used to extract key parameters such as the convective and the acoustic component of the turbulent flow from CFD and/or experimental data whenever available. This work focuses on the validation of the wind noise source characterization method and the vibro-acoustic models on which the wind noise sources are applied.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2000년도 추계학술대회 논문집
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• pp.162-167
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• 2000

The warm deep drawability in square cup drawing is investigated about a newly developed high-strength steel sheet with retained austenite which is transformed into martensite during forming. For this investigation, six steps of temperature ranges, from room temperature to $250^{\circ}C$, and five kinds of drawing ratio, from 2.2 to 2.6 were adopted. As a result the maximum drawing force and the maximum drawing depth were affected by the elevated temperatures, and the more stable thickness strain distribution was observed to the elevated temperatures. But blue shortness happened over $200^{\circ}C$. The FEM analysis using the LS-DYNA code is adopted to compare the experimental results with the analytical results for thickness strain distribution.