• Journal of Plant Biotechnology
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• v.40 no.2
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• pp.79-87
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• 2013

The aim of this study was to establish plant regeneration from leaf explants of Sedum tosaense Makino, which is globally rare and endangered species. The leaf explants of S. tosaense were cultured on the MS medium supplemented with different concentration of BA and NAA for callus induction. Callus induction was showed the highest (100%) on MS medium containing $2.0mg{\cdot}L^{-1}$ BA and $1.0mg{\cdot}L^{-1}$ NAA. The highest number of shoots were regenerated when callus were cultured on MS medium containing $2.0mg{\cdot}L^{-1}$ BA and $1.0mg{\cdot}L^{-1}$ NAA for 5 weeks. The axillary bud were cultured on the MS media supplemented with combination of BA and NAA for in vitro propagation. The highest number of adventitious shoot (7.9 per explants) formed at $1.0mg{\cdot}L^{-1}$ NAA and $2.0mg{\cdot}L^{-1}$ BA. For rooting, MS medium supplemented with or without $2.0g{\cdot}L^{-1}$ activated charcoal was tested. The optimal results were observed using MS medium supplemented with $2.0g{\cdot}L^{-1}$ activated charcoal, on which 85.7 (No. of root), 4.6 cm (length of root). 1,200 ppm $CO_2$ and 350 ppm $CO_2$ were supplied for make certain the effects of $CO_2$ on pre-acclimatization by photoautotrophic culture. 1,200 ppm $CO_2$ treatment was established higher than 350 ppm $CO_2$ treatment. Soil acclimatization of in vitro plantlets was the best in mixture soil consisted of peat moss and perlite with 100% survival rate and they showed the maximum growth.

• The Korean Journal of Petroleum Geology
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• v.3 no.1 s.4
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• pp.1-15
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• 1995

Seismic reflection profiles and exploratory drilling well samples from the southern marginal-continental shelf basin of Korea delineate that the Tertiary sedimentary sequences can be grouped into five sequences (Sequence A, Sequence B, Sequence C, Sequence D and Sequence E, in descending order). Paleontologic data, K-Ar age datings, correlation with tuff layers and sequence stratigraphic analysis reveal that the sequences A, B, C, D and E can be considered as the deposits of Holocene $\~$ Pleistocene, Pliocene, Late Miocene, Early $\~$ Middle Miocene and Oligocene, respectively. The sequence stratigraphic and structural analyses suggest that the southern part of the Cheju Basin had experienced severe folding and faulting. NE-SW trending strike-slip movement is responsible for the deformation. The sinistral movement of strike-slip fault ceased before the deposition of Sequence B. Age dating and rare-earth elements analysis of volvanic rocks reveal+ that the Sequence D was deposited during the Early $\~$ Middle Miocene and the Sequence I was deposited earlier than the deposition of the Green Tuff Formation. Sedimentary petrological studies indicate that sediments of the Sequence I came from the continental block provenance. After the deposition of the Sequence E, uplift of the source area resulted in increase of sediment supply, subsidence and volcanic activities. The Sequence D show these factors and the sediments of the Sequence D are considered to be transported from the recycled orogenic belt.

• Journal of Life Science
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• v.23 no.2
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• pp.228-236
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• 2013

This study was aimed at investigating whether dietary therapy using medicinal enzyme powder is effective in reducing constipation caused by loperamide in rats. Nine-week-old male Sprague Dawley were subdivided into 4 groups: normal diet group (C), loperamide treatment and normal diet (CL), medicinal enzyme powder diet (E), and loperamide treatment and medicinal enzyme powder diet (EL). Constipation was induced by subcutaneous injection of loperamide (1.5 mg/kg) 3 days prior to sacrifice. The treatment with loperamide led to an increase in weight gain, a decrease in the number and wet weight of fecal pellets, and a decrease in intestinal motility. The administration of the medicinal enzyme powder significantly reduced weight gain but increased intestinal mobility compared with the loperamide-treated group. The treatment with loperamide in the normal diet group reduced the activities of both suggesting that constipation may be involved in the low level of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT). Additionally, the loperamide treatment in the medicinal enzyme powder diet group increased the level of GOT, but reduced the level of GPT. Loperamide treatment also reduced cholesterol and increased the atherogenic index (AI) and cardiac risk factors (CRFs). Interestingly, the treatment with the medicinal enzyme powder effectively attenuated both the increase in AI and the reduction in high density lipopretein (HDL)-cholesterol, caused by the treatment with loperamide. Although there were no significant differences in the blood protein level, including hemoglobin and hematocrit, between the normal diet group and the loperamide-treated group, the administration of the medicinal enzyme powder to the loperamide-treated group effectively increased the levels of both hemoglobin and hematocrit. Collectively, the results demonstrate that the medicinal enzyme powder can help to combat the negative events caused by constipation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.7
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• pp.586-603
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• 2004

One of the subtle problems that make noise control difficult for engineers is “the invisibility of noise or sound.” The visual image of noise often helps to determine an appropriate means for noise control. There have been many attempts to fulfill this rather challenging objective. Theoretical or numerical means to visualize the sound field have been attempted and as a result, a great deal of progress has been accomplished, for example in the field of visualization of turbulent noise. However, most of the numerical methods are not quite ready to be applied practically to noise control issues. In the meantime, fast progress has made it possible instrumentally by using multiple microphones and fast signal processing systems, although these systems are not perfect but are useful. The state of the art system is recently available but still has many problematic issues : for example, how we can implement the visualized noise field. The constructed noise or sound picture always consists of bias and random errors, and consequently it is often difficult to determine the origin of the noise and the spatial shape of noise, as highlighted in the title. The first part of this paper introduces a brief history, which is associated with “sound visualization,” from Leonardo da Vinci's famous drawing on vortex street (Fig. 1) to modern acoustic holography and what has been accomplished by a line or surface array. The second part introduces the difficulties and the recent studies. These include de-Dopplerization and do-reverberation methods. The former is essential for visualizing a moving noise source, such as cars or trains. The latter relates to what produces noise in a room or closed space. Another mar issue associated this sound/noise visualization is whether or not Ivecan distinguish mutual dependence of noise in space : for example, we are asked to answer the question, “Can we see two birds singing or one bird with two beaks?"

• Journal of Nutrition and Health
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• v.17 no.2
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• pp.126-136
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• 1984

The long-term effects of vegetable and animal high fat diet on the lipid metabolism were investigated in male weaning rats. The rats were fed one of four semipurified diet ad libitum : control diet supplied 12% of calories as fat(control group), low fat diet supplied 3% of calories as fat (3% F group), 45% corn oil diet supplied 45% calories from corn oil (45% C group) and 45% butte. fat diet supplied 45% calories from butter fat (45 % B group). Incorporation of $acetate-1-^{14}C$ into lipid of liver, serum and adipose tissue as well as exhalation of $^{14}CO_{2}$ from $acetate-1-^{14}C$ were observed in rats fed for 4,8 and 12 weeks. The weigh of epididymal adipose tissue of rats, fed 45% corn oil and 45% butter fat . from 4 weeks to 8 weeks were higher, but not different at 12 weeks, compared with those of control group. The weight of abdominal adipose tissue appeared to be similar to those of epididymal adipose tissue. Incorporations of $acetate-1-^{14}C$ into lipid of liver were remarkably decreased in high fat diet groups, especially in 45% C group, but in 3% F group were increased more than those of control group. Incorporations of $acetate-1-^{14}C$ into epididymal adipose tissue in 3% F, 45% C and 45% B group at 8 weeks were remarkably increased but not different at 12 weeks, compared with those of control group. The incorporation of {acetate-1-}^{14}C into abdominal adipose tissue appeared to be similar to those of epididymal adipose tissue. Incorporations of $acetate-1-^{14}C$ into lipid of serum in 45% C and 45% B group were reduced reasonably at 4 and 8 weeks of diet as compared with those of control group. Exhalation of $^{14}CO_{2}$ was increased to maximum level at 10 minutes after injection of $acetate-1-^{14}C$. Expiration of $^{14}CO_{2}$ in 45% C and 45% B group were higher than those in 3% F and control group for initial 5 minutes after injection, but expirations of $^{14}CO_{2}$ did not have significant difference among groups of diet since 10 minutes.

• Restorative Dentistry and Endodontics
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• v.30 no.1
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• pp.58-65
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• 2005

The purpose of this study was to compare the shaping ability of the three $ProTaper^{(R)}$ instrumentation techniques in simulated canals. Thirty resin blocks were divided into 3 groups with 10 canals each. Each group was instrumented with manual $ProTaper^{(R)}$ (Group M), rotary $ProTaper^{(R)}$ (Group R), and hybrid technique (Group H). Canal preparation time was recorded. The images of pre- and post-instrumented root canals were scanned and superimposed. The amounts of canal deviation, total canal width, inner canal width, outer canal width and centering ratio were measured at apical 1, 2, 3, 4, 5 and 6 mm levels 1. Canal preparation time was the shortest in R group (p < 0.05). 2. The amounts of total canal width in R group was generally larger than the other groups, but no significant differences were observed except at the 1, 3 mm levels (p > 0.05) .3. The amounts of inner canal width in R group was larger than M group at the 1 mm level and H group was larger than R group at the 6 mm level (p < 0.05). The amounts of outer canal width in R group was larger than H group only at the 1 mm level (p < 0.05). 4. The direction of canal deviation in H, R group at the 1, 2, 3 mm levels was outward and that in M group at the 1, 2 mm levels was inward. The amounts of canal deviation in H group was larger than R group at the 6 mm level (p < 0.05). 5. The amounts of centering ratio in H group was larger than R group at the 6 mm level (p < 0.05).

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.77-86
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• 1986

The purpose of this study is to estimate an optimum formula of rainfall intensity on basis of the characteristics for short period of rainfall duration in Kyungpook province for the design of urban sewerage and small basin drain system. Results studied are as follows; 1. The optimum method for Taegu and Pohang, Iwai's and Gumbel-Chow's method are recommended respectively. 2. The opotimum type of rainfall intensity for these area, $I=\frac{a}{\sqrt{t}+b}$ (Japanese type), is confirmed with 2.52~4.17 and 1.86~4.54 as a standard deviation for Taegu and Pohang respectively. The optimum formula of rainfall intensity are as follows. Taegu : T : 200 year - $I=\frac{824}{\sqrt{t}+1.5414}$ T : 100 year - $I=\frac{751}{\sqrt{t}+1.4902}$ T : 50 year - $I=\frac{678}{\sqrt{t}+1.4437}$ T : 30 year - $I=\frac{623}{\sqrt{t}+1.4017}$ T : 20 year - $I=\frac{580}{\sqrt{t}+1.3721}$ T : 10 year - $I=\frac{502}{\sqrt{t}+1.3145}$ T : 5 year - $I=\frac{418}{\sqrt{t}+1.2515}$ Pohang : T : 200 year - $I=\frac{468}{\sqrt{t}+1.1468}$ T : 100 year - $I=\frac{429}{\sqrt{t}+1.1605}$ T : 50 year - $I=\frac{391}{\sqrt{t}+1.1852}$ T : 30 year - $I=\frac{362}{\sqrt{t}+1.2033}$ T : 20 year - $I=\frac{339}{\sqrt{t}+1.2229}$ T : 10 year - $I=\frac{299}{\sqrt{t}+1.2578}$ T : 5 year - $I=\frac{257}{\sqrt{t}+1.3026}$ 3. Significant I.D.F. curves derived should be applied to estimate a suitable rainfall intensity and rainfall duration.

• Journal of Korean Society of Forest Science
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• v.47 no.1
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• pp.16-26
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• 1980

Soluble carbohydrates and free amino acids in the terminal buds of Pinus elliottii were analyzed to understand the nutritional status of the buds during the period of female strobilus initiation. Grafted, 18-year-old slash pine trees in a seed orchard were divided into two groups, abundant-flowering (AFG) and poor-flowering group (PFG) according to their flowering history. Four types of terminal buds, with two types from each group, were examined: (1) large buds in upper crown (female-producing buds) and small buds in lower crown (male-producing) in AFG, (2) large buds in upper crown (vegetative buds) and small buds in lower crown (male-producing) in PFG. Bud samples were collected four times from late July to early September. Free sugars and free amino acids (75% ethanol-soluble) were determined by gas chromatography and automatic analysis, respectively. Sugar content in the large buds of both groups was greater than in the small buds of the same group. Fructose and glucose were major sugars found in the bud tissue. Arginine was the most abundant amino acid in all four types of buds, with the concentration increased from 23% in late July to 60% in early September. Arginine and total amino acid content in the female-producing buds of AFG was much lower than three other types of buds. When female-producing buds and male-producing buds of AFG were compared in their arginine content, the former contained about same amount as the latter in late July, but showed one-fourth of the latter in early September. The low level of argining in the female-producing buds suggested a minimal or negative role of arginine in the initiation of female flower primordia. A higher sugar to amino acid ratio was observed with female-producing buds of AFG than with vegetative or male-producing buds of either flowering group. The low amino acid content in the female­producing buds suggested that initiation of female strobilus primordia was associated with temporary reduction in the metabolic activity of the buds.

• Journal of the Korean Geotechnical Society
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• v.34 no.2
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• pp.19-32
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• 2018

During the process of gas hydrate extraction in the deep seabed, fine diatom particle migration occurs, which causes the seabed slope failure and the productivity deterioration of the gas hydrate. Therefore, a study related with the changes of the ground characteristics due to the fine particle migration is required. The objective of this study is to investigate the change of hydraulic properties of sand due to the migration of fine diatom particle in sandy soils. In order to simulate the sediments of the Ulleung basin gas hydrate in the East Sea, fifteen sand-diatom mixtures that have different diatom volume fractions (DVF) are prepared. During the falling head permeability tests, the coefficients of permeability are measured according to the DVF. In addition, for the simulation of the fine diatom particle migration, constant head permeability tests are conducted by applying the hydraulic pressures of 3 kPa, 6kPa, and 9 kPa on a specimen composed of two layers: a specimen with 50% DVF in upper layer and a specimen with 0% DVF in lower layer. Furthermore, the coefficient of permeability and the electrical resistivity of the migration zone are measured during the constant head permeability test. The falling head permeability tests show that the coefficient of permeability decreases as the DVF of the specimen increases. In addition, the gradient of the coefficient of permeability curve decreases in the DVF range of 10%~50% compared with that of 0%~10%, and increases above 50% in DVF. The result of constant head permeability tests shows that the coefficient of permeability decreases and electrical resistivity increases in the migration zone due to the fine diatom particle migration. This study demonstrates that fine diatom particle migration reduces the permeability of the soils and the behavior of the migration zone due to the fine diatom particle migration may be estimated based on the reversal relationship between the coefficient of permeability and the electrical resistivity.

• Journal of the Korean Geotechnical Society
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• v.33 no.11
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• pp.21-34
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• 2017

The ground penetrating radar (GPR) signal can be measured with different amplitudes according to the directivity, so the directivity of the antenna should be considered. The objective of this study is to investigate the directivity of antenna by analyzing the reflection characteristics of electromagnetic waves radiated from the antenna, and to evaluate effective range of angle that can inspect an abnormal area according to the directivity of antenna. For the measurement of the directivity, a circular metal bar is used as reflector and the signals are measured by changing the angle and the distance between reflector and antenna in the E- and H-plane. The boundary distance between the near field and the far field is determined by analyzing the amplitudes of reflected signals, and two points with different distances from each of near and far fields are designated to analyze radiation patterns in near and far fields. As a result of radiation pattern measurement, in the near field, minor lobes are observed at angle section at more than $50^{\circ}$ in both E- and H-plane. Therefore, antenna has the directivity for the direction of main lobe and minor lobes in near field. In the far field, antenna has the directivity for a single direction of main lobe because minor lobes are not observed. The amplitude of the signal reflected from the near field is unstable, but it can be distinguished from noise. Therefore, in the near field, the ground anomaly can be detected with high reliability. On the other hand, the amplitude of the signal reflected from the far field is stable, but it is hard to distinguish between reflected signal and noise because of the excessive loss of electromagnetic wave. The analyses of directivity in the near and the far fields performed in this study may be effectively used to improve the reliability of the analyses of abnormal area.