• Journal of Welding and Joining
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• v.17 no.6
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• pp.84-89
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• 1999

Most of ferrous b.c.c weld materials may experience martensitic transformation during rapid cooling after welding. It is well known that volume expansion due to the phase transformation could influence on the relaxation of welding residual stress. To apply this effect practically, it is a prerequisite to establish a numerical model which is able to estimate the effect of phase transformation on residual stress relaxation quantitatively. For this purpose, the analysis is carried out in two regions. i.e., heating and cooling, because the variation of material properties following a phase transformation in cooling is different in comparison with the case in heating, even at the same temperature. The variation of material properties following phase transformation is considered by the adjustment of specific heat and thermal expansion coefficient, and the distribution of residual stress in analysis is compared with that of experiment by previous study. consequently, in this study, simplified numerical procedures considering phase transformation, which based on a commercial finite element package was established through comparing with the experimental data of residual stress distribution by other researcher. To consider the phase transformation effect on residual stress relaxation, the transition of mechanical and thermal property such as thermal expansion coefficient and specific heat capacity was found by try and error method in this analysis.

• Proceedings of the KSRS Conference
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• v.2
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• pp.856-859
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• 2006

In river with bar, the characteristics of its physical conditions have a close relationship with bar morphology. In this paper, a monitoring approach of bar transformation in the Han River Estuary is presented using RADARSAT/SAR Images. The estuary is divided into North and South Korea and its area is blocked by CCL(Civil Control Line). Satellite remote sensing, therefore, is uniquely suited to monitoring bar transformation. Based on SAR signatures for bars, bar transformation is investigated from 2000 to 2005, and monitoring of suspended-silt transportations from terrestrial runoff is tried to understand the morphology during the events of severe rain storm. SAR data did not reveal clearly the bar locations because of most of data acquisitions during high tides from 6.8 m to 9.0 m. Even though the problem, it could be said that in the estuary vegetated area and natural levees are developed well, but bars and shifted after an event like a flood. It is also showed that suspended solids such as silt transported through the estuary could contribute highly to a sedimentation environment around Incheon.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.5
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• pp.434-439
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• 2004

Medicago truncatula is a model plant for molecular genetic studies of legumes and plant-microbe interactions. To accelerate finding of genes that play roles in the early stages of nodulation and stress responses, a trans-genic plant was developed that contains a promoter­reporter fusion. The promoter of rip], a Rhizobium-induced peroxidase gene, was fused to the coding region of $\beta-glucuronidase (GUS)$ gene and inserted into a modified plant transformation vector, pSLJ525YN, in which the bar gene was preserved from the original plasmid but the neomycin phosphotransferase gene was replaced by a polylinker. Transformation of M. truncatula was carried out by vacuum infiltration of young seedlings with Agrobacterium. Despite low survival rates of infiltrated seedlings, three independent transformants were obtained from repeated experiments. Southern blot analyses revealed that 7 of 8 transgenic plants of the T 1 generation contained the bar gene whereas 6 $T_1$ plants contained the GUS gene. These results indicate that vacuum infiltration is an effective method for transformation of M. truncatula. The progeny seeds of the transgenic plants will be useful for mutagenesis and identification of genes that are placed upstream and may influence the expression of rip] in cellular signaling processes including nodulation.

• The Journal of Internal Korean Medicine
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• v.37 no.5
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• pp.786-795
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• 2016

Objective: To evaluate the effectiveness of traditional Korean medicine treatment (TKM) on a patient with ACA infarction and hemorrhagic transformation with hemiplegia and urinary disturbance. Methods: A patient diagnosed with left anterior cerebral artery (ACA) infarction and hemorrhagic transformation was treated with electroacupuncture, moxibustion, and herbal medicine. Results: Improvements in the Manual Muscle Test (MMT), modified Barthel Index (MBI), National Institutes of Health Stroke Scale (NIHSS), modified Rankin scale (mRS), and K-MMSE were observed following the TKM treatment [MMT Gr. (3/0)→Gr. (4+/4+), MBI 20→89, NIHSS 8→2, mRS 5→1, MMSE-K 21→28]. Conclusion: TKM treatment could help improve the symptoms of patients with ACA infarction and hemorrhagic transformation.

• Journal of the Korean Ceramic Society
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• v.27 no.6
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• pp.808-816
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• 1990

The thermal behavior of transformation and characteristics of seeded sample powders prepared by simultaneous $\alpha$-Al2O3 seed addition with water on the Al-sec-butoxide hydrolysis were studied. $\alpha$-Al2O3 seed particles are shown to act as nuclei for transformation of $\theta$-to $\alpha$-Al2O3 and to result in an increase in thetransformation kinetics and lowering of the transformation temperature by as much as 143$^{\circ}C$. Simultaneous seed addition on the hydrolysis resulted in uniform dispersin and creation of nucleation site on seed surface and only 0.1wt% seeding lowered the transformation temperature by as much as 115$^{\circ}C$. For 3wt% seed addition, $\alpha$-Al2O3 single phase was obtained at 95$0^{\circ}C$ for 100 minutes and the specific surface area of products were lowered to 11.9$m^2$/g as compared with that of $\alpha$-Al2O3 powder prepared without seed at 115$0^{\circ}C$ ; 15.1$m^2$/g due to depression of vermicular structure growth.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.27-33
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• 2003

The optimal condition of in vitro regeneration and transformation were investigated for newly bred potato varieties in Korea. Leaf and internodal stem tissues of 'Chubak', 'Namsuh', 'Jasim', 'Jopung' and 'Jowon' were used to investigate the influence of growth regulator on regeneration efficiency The effect of phenolic compound acetosyringone on gene transformation efficiency was also investigated. Leaf tissue of 'Jowon' and internodal stem tissues of 'Jopung' were showed high regeneration efficiency on M5 medium supplemented with 0.1 mg/L GA₃, 2.0 mg/L Zeatin and 0.01 mg/L NAA. The other three potato cultivars were showed low regeneration efficiency less than 25%. The effect of acetosyringone on Agrobacterium-mediated gene transformation with leaf and internodal stem tissues were noticeable. By adding the 75 μM of acetosyringone during the Agrobacterium innoculation, the transformation efficiency was increased up to 1.5∼4.0 fold compare to non-treated control. In case of 'Jowon' the transformation efficiency was 87.9% in leaf tissue and 'Jopung' was 68.4% in internodal stem tissues.

• Journal of Plant Biotechnology
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• v.3 no.3
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• pp.113-121
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• 2001

The use of a marker gene in a transformation process aims to give a selective advantage to the transformed cells, allowing them to grow faster and better, and to kill the non-transformed cells. In general, the selective gene is introduced into plant genome along with the genes of interest. In some cases, the marker gene can be the gene of interest that will confer an agronomic characteristic, such as herbicide resistance. In this review we list and discuss the use of the most common selective marker genes on plant transformation and the effects of their respective selective agents. These genes could be divided in categories according their mode of action: genes that confer resistance to antibiotics and herbicides; and genes for positive selection. The contention of the marker gene flow through chloroplast transformation is further discussed. Moreover, strategies to recover marker-free transgenic plants, involving multi-auto-transformation (MAT), co-transformation, site specific recombination and intragenomic relocation of transgenes through transposable elements, are also reviewed.

• Korean Journal of Remote Sensing
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• v.26 no.1
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• pp.39-45
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• 2010

This study used the keypoint observed simultaneously on two images and on twodimensional intensity image data, which was obtained along with the two point clouds data that were approached for automatic focus among points on terrestrial LiDAR data, and selected matching point through SIFT algorithm. Also, for matching error diploid, RANSAC algorithm was applied to improve the accuracy of focus. As calculating the degree of three-dimensional rotating transformation, which is the transformation-type parameters between two points, and also the moving amounts of vertical/horizontal, the result was compared with the existing result by hand. As testing the building of College of Science at Konkuk University, the difference of the transformation parameters between the one through automatic matching and the one by hand showed 0.011m, 0.008m, and 0.052m in X, Y, Z directions, which concluded to be used as the data for automatic focus.

• Journal of the Korean Society for Heat Treatment
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• v.13 no.4
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• pp.265-271
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• 2000

The microstructural change and transformation characteristics with cooling rate i.e. wheel speed were investigated in 82.8wt%Cu-12.8wt%Al-4.3wt%Ni SMA ribbons fabricated by melt-spinning. The thickness and width of ribbon were decreased with increasing wheel speed, while the uniformity of it was improved. At same wheel speed, the grain size of the contact surface of ribbon was smaller than that of free surface. The mean grain size was decreased with increasing wheel speed, resulted in obtaining grains with $3{\mu}m$ in mean diameter in the wheel speed of 30 m/s. However, micro-voids and cracks at grain boundary could be observed at higher wheel speed. $M_s$ and $A_s$ temperatures were decreased, and $M_s{\sim}M_f$ and $A_s{\sim}A_f$ temperature ranges were broadened with increasing wheel speed. All the ribbons were retained the ordered $D0_3$ due to rapid cooling, the volume fraction of it was increased with increasing wheel speed.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1390-1394
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• 2004

We have achieved efficient transformation system for forage-type tall fescue plants by Agrobacterium tumefaciens. Mature seed-derived embryogenic calli were infected and co-cultivated with each of three A. tumefaciens strains, all of which harbored a standard binary vector pIG121Hm encoding the neomycin phosphotransferase II (NPTII), hygromycin phosphotransferase (HPT) and intron-containing $\beta$-glucuronidase (intron-GUS) genes in the T-DNA region. Transformation efficiency was influenced by the A. tumefaciens strain, addition of the phenolic compound acetosyringone and duration of vacuum treatment. Of the three A. tumefaciens strains tested, EHA101/pIG121Hm was found to be most effective followed by GV3101/pIG121Hm and LBA4404/pIG121Hm for transient GUS expression after 3 days co-cultivation. Inclusion of 100 $\mu$M acetosyringone in both the inoculation and co-cultivation media lead to an improvement in transient GUS expression observed in targeted calli. Vacuum treatment during infection of calli with A. tumefaciens strains increased transformation efficiency. The highest stable transformation efficiency of transgenic plants was obtained when mature seed-derived calli infected with A. tumefaciens EHA101/pIG121Hm in the presence of 100 $\mu$M acetosyringone and vacuum treatment for 30 min. Southern blot analysis indicated integration of the transgene into the genome of tall fescue. The transformation system developed in this study would be useful for Agrobacterium-mediated genetic transformation of tall fescue plants with genes of agronomic importance.