• Korean Journal of Materials Research
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• v.9 no.5
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• pp.460-466
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• 1999

The deep level electron traps in AP-MOCVD GaAs/undoped Al\ulcornerGa\ulcornerAs/n-type GaAs heterostructures have been investigated by means of Deep Level Transient Spectroscopy DLTS). In terms of the experimental procedure, GaAs/undoped Al\ulcornerGa\ulcornerAs/n-type GaAs heterostructures were deposited on 2" undoped semi-insulating GaAs wafers by the AP-MOCVD method at $650^{\circ}C$ with TMGa, AsH3, TMAl, and SiH4 gases. The n-type GaAs conduction layers were doped with Si to the target concentration of about 2$\times$10\ulcornercm\ulcorner. The Al content was targeted to x=0.5 and the thicknesses of Al\ulcornerGa\ulcornerAs layers were targeted from 0 to 40 nm. In order to investigate the electrical characteristics, an array of Schottky diodes was built on the heterostructures by the lift-off process and Al thermal evaporation. Among the key results of this experiment, the deep level electron traps at 0.742~0.777 eV and 0.359~0.680 eV were observed in the heterostructures; however, only a 0.787 eV level was detected in n-type GaAs samples without the Al\ulcornerGa\ulcornerAs overlayer. It may be concluded that the 0.787 eV level is an EL2 level and that the 0.742~0.777 eV levels are related to EL2 and residual oxygen impurities which are usually found in MOCVD GaAs and Al\ulcornerGa\ulcornerAs materials grown at $630~660^{\circ}C$. The 0.359~0.680 eV levels may be due to the defects related with the al-O complex and residual Si impurities which are also usually known to exist in the MOCVD materials. Particularly, as the Si doping concentration in the n-type GaAs layer increased, the electron trap concentrations in the heterostructure materials and the magnitude of the C-V hysteresis in the Schottky diodes also increased, indicating that all are intimately related.ated.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.283-290
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• 2014

This experiment had been conducted to determine optimal culture conditions for the growth and cut flowers of Calla (Zantedeschia 'Black Magic' 'Golden Affair') in highlands. Tubers of calla 'Black Magic' was treated with 0, 100, and $200mg{\cdot}L^{-1}$ concentration of $GA_3$. ABA content in tubers and roots were twice higher ($20-25pmol{\cdot}mL^{-1}$) in control than in $GA_3$ treated tubers and roots. ABA contents in tubers was not consistent but ABA contents in roots increased with increasing $GA_3$ concentration. However ABA is in inverse proportion to GA. It was mean that GA of high contents was ABA of low contents. Calla 'Golden Affair' was treated with different mulching materials (Control, black PE, Reflective film, Rice hull) and $GA_3$ concentrations (0, 50, 100 and $200mg{\cdot}L^{-1}$). It was largest in the length of flower at mulching of reflective film, Rice hull and it was greatest in the number of cut flowers at the treated with $200mg{\cdot}L^{-1}$ $GA_3$, Therefore the proper condition was at $200mg{\cdot}L^{-1}$ $GA_3$ with reflective film mulching.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.250-254
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• 1995

Isolated barley aleurone layers were used to examine response of (1-3)- and $(1-3,1-4)-{\beta}-glucanases{\;}to{\;}GA_3$. Protein content and levels of (1-3)- and $(1-3,1-4)-{\beta}-glucanases$ increased in the presense of added $GA_3$. However, (1-3)- and $(1-3,1-4)-{\beta}-glucanases$ showed different response to $GA_3$ in their production and secretion patterns. $(1-3,1-4)-{\beta}-glucanases$ showed higher increase in enzyme activity than $(1-3)-{\beta}-glucanase$ in the early stage of$GA_3$treatment. Secretion of enzyme by $GA_3$ into the surrounding medium was more enhanced in $(1-3,1-4)-{\beta}-glucanases$ than in $(1-3)-{\beta}-glucanase$, The differential response of the enzymes might be related to the physiological role of the enzymes in germination of barley grain.

• Journal of the Korean Magnetics Society
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• v.7 no.1
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• pp.44-48
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• 1997

The nanocrystalline Nd-Fe-B alloys with low Nd content were prepared by rapid solidification technique. The alloys consist of both$\alpha$-Fe as the main phase and $Nd_2Fe_{14}B_1$ as a secondary phase and have an ultrafine grain structure of about 30 nm. The addition of Ga in $Nd_4Fe_{82}B_{10}Mo_3Cu_1$ alloy increases remanence up to 1.29 T and improves squareness. The nanocrystalline $Nd_5Fe_{81}B_9Mo_3Cu_1Ga_1$ alloy has a volume fraction of $Nd_2Fe_{14}B_1$ phase of around 35% due to the increase of Nd content and shows an improved coercivity. The remanence, coercivity and energy product of optimally annealed nanocrystalline $Nd_5Fe_{81}B_9Mo_3Cu_1Ga_1$ alloy are 1.24 T, 257.4 kA/m (3.23 kOe), and 100.3 kJ/ ㎥ (12.6 MGOe), respectively.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.673-677
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• 2005

This experiment was conducted to clarify the effect of pyroligneous liquor on endogenous substances that were GA (gibberelic acid)-like substances, starch, and protein of Neofinetia falcata cultured in vitro. When seedlings of Neofinetia falcata were treated with several concentrations (0, 0.5, 1.0, 2.0, 3.0 ml/L) of pyroligneous liquor, the growth of seedlings was enhanced in 1.0ml/L pyroligneous liquor added media. The activity of GA-like substances was lower in the leaf, but higher in the and root than that of the control. The content of starch in 1.0ml/L pyroligneous liquor was lower in the leaf, but higher in the root than that of the control. And the content of protein in 1.0ml/L pyroligneous liquor was also lower in the leaf, but higher in the root than that of the control.

• Journal of Plant Biotechnology
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• v.48 no.3
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• pp.186-192
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• 2021

The roots of Korean ginseng (Panax ginseng) have a long history of usage as a medicinal drug. Ginsenosides, a group of triterpenioid saponins in ginseng, have been reported to show important pharmacological effects. Many studies have attempted to identify the ginsenoside synthesis pathways of P. ginseng and to increase crop productivity. Recent studies have shown that exogenous gibberellin (GA) treatments promote storage root secondary growth by integration of the modulating cambium stem cell homeostasis with a secondary cell wall-related gene network. However, the dynamic regulation of ginsenoside synthesis-related genes and their contents by external signaling cues has been rarely evaluated. In this study, we confirmed that GA treatment not only enhanced the secondary growth of P. ginseng storage roots, but also significantly enriched the terpenoid biosynthesis process in RNA-seq analysis. Consistently, we also found that the expression of most genes involved in the ginsenoside synthesis pathways, including those encoding methylerythritol-4-phosphate (MEP) and mevalonate (MVA), and the saponin content in both leaves and roots was increased by exogenous GA application. These results can be used in future development of biotechnology for ginseng breeding and enhancement of saponin content.

• Journal of the Semiconductor & Display Technology
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• v.7 no.4
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• pp.13-18
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• 2008

This paper explores a content-based image retrieval framework with relevance feedback based on genetic algorithm (GA). This framework adopts GA to learn the user preferences using the similarity functions defined for all available descriptors. The objective of the GA-based learning methods is to learn the user preferences using the similarity functions and to find a descriptor combination function that best represents the user perception. Experiments were performed to validate the proposed frameworks. The experiments employed the natural image databases and color and texture descriptors to represent the content of database images. The proposed frameworks were compared with the other two relevance feedback methods regarding effectiveness in image retrieval tasks. Experiment results demonstrate the superiority of the proposed method.

• International Journal of Costume and Fashion
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• v.14 no.2
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• pp.33-50
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• 2014

Investigations on the symbolic role, spiritual health benefits and efficacy of the clothing items of the Ga wolomo (chief priest) have received little attention. Highlighting the relevance of these clothes, this paper focuses on the chief priest's dress code for his appointment, confinement, ordination, ceremonial and daily life activities. Data were collected through content analysis, participant observation and interviews with people from selected Ga communities, such as La, Teshie and Ga Mashie. The findings revealed that the selection of the chief priest is confirmed with a special clothing item. His traditional clothes and adornment also have meanings, importance and symbolic interpretations; explained in their uses, colour and style. As the spiritual head, the role of the chief priest's costume is very distinguished and symbolic in executing his duties; protecting, strengthening faith, confidence and assurance during spiritual healing, and when solving pertinent problems in the community. The paper concludes by recommending further research and documentation on other aspects of the Ga clothing culture, such as hand items and hair styles from the pre-colonial period to the present.

• Journal of agriculture & life science
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• v.43 no.2
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• pp.23-30
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• 2009

The object of this study was to evaluate the effect of the gibberellin treatment on fruit enlargement and ripening promotion in 'Niitaka' pear(Pyms pynfolia). Fruit weight was similar between $GA_{4+7}$ treatments and the gibberellin-paste control, but fairly increased of fruit weight compared to non-treatment Most effective time for $GA_{4+7}$ treatment to increase diameter and length was on 35 and 40 days after full bloom, respectively. Shape index was similar in all treatments. Fruit enlargement at the period of early growth, $GA_{4+7}$ 2.4% treatment was remarkably effective than $GA_{3}+GA_{4+7}$ 2.7% treatment or non-treatment However at the period of maturity, $GA_{4+7}$ 2.4% treatment and $GA_{3}+GA_{4+7}$ 2.7% treatment showed little differences in fruit enlargement and coloring. In maturing promotion effect, young fruit treated with $GA_{3}+GA_{4+7}$ showed similar fruit coloring to ethephon treatment on 35 days after full bloom, and both of those treatments promoted fruit coloring than non- treatment about 6 days. $GA_{3}+GA_{4+7}$ treatments resulted higher solid content and decreased acidity than non-treatment However, there was no differences in fruit hardness comparing to non-treatment As a result, gibberellin was most effective in fruit enlargement, so as all $GA_{3}+GA_{4+7}$ treatments were more effective on fruit enlargement than ethephon treatment or non-treatment Specifically, when $GA_{3}+GA_{4+7}$ was treated 35days after full bloom of flower, the diameter, the length and the shape of fruit index were best, and fruit coloring was good as well.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.88-93
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• 2005

The functional vice (Oryza sativa L.) has been highly regarded recently, in the change of rice maykets in the world. Goami2 (GA), one of the functional rice varieties, was developed from high-quality rice, Ilpumbyeo (IP). From the previous study, GA has been proved its beneficial effect on the improvement of metabolic control and body weight reduction especially in obesity, We could certain that GA was very difficult to be gelatinized due to the micro lump shown in the Scanning electron micrographs (SEM) photos. To improve its cooking quality, we investigated the changes of physicochemical properties, which were differentiated by the conditions of milling and blending. As GA was milled every $2\%$ until eliminating $12\%$, the nitrogen content was decreased linearly. But the decreasing rate of nitrogen content of GA during milling process was relatively lower than that of IP. Thus, we assumed that GA has relatively high nitrogen in inner starch of grain. The degree of milling had no effect on the gelatinization of cooked GA, but affected lightness and whiteness linearly, which were ranged in normal values when the rice was milled more than $10\%$ in weight. So we could concluded that the milling process was not proper to improve cooking quality of GA. And we could suggested that GA was needed to soak into water at least one hour before cooking by it water absorption rate at normal temperature$(21^{\circ}C)$ and sensory evaluation. From the texture analysis, cooked GA had higher hardness than other varieties. Therefore, we blended GA with IP, Baekjinju(BJ) and Hwasunchalbyeo(HS), then subjected to sensory evaluation. All evaluation items including the sensory preference were the highest scores for the rice blended with glutinous rice varieties, BJ and HS.