• Korean Journal of Environmental Agriculture
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• 제24권4호
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• pp.404-408
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• 2005

In order to obtain the basic information far agricultural utilization of Germanium (Ge), the growth characteristics and germanium absorption in lettuce were investigated with different concentration of germanium in soil. This experiment was carried out in the waster pot $(15,000^{-1}a)$. Germanium concentrations in soil for lettuce cultivation were maintained at 0.26, 2.0, 4.0, 6.0 and $8.0mg\;kg^{-1}$, respectively. The content of germanium in lettuce was increased with the increase of germanium concentration in soil. When lettuce was cultivated on soil supplemented with Ge $8.0mg\;kg^{-1}$, germanium phytotoxicity (reduction of plant height, No. of leaf and fresh weight) was not observed. When lettuce was cultivated on soil supplemented with Ge 4.0 and $8.0mg\;kg^{-1}$, it germanium content were found 0.75 and $1.27mg\;kg^{-1}$, respectively. Germanium absorption efficiency of lettuce was not different by germanium concentrations in the soil. When lettuce was cultivated on soil supplemented with Ge 2.0, 4.0 and $8.0mg\;kg^{-1}$, its absorption germanium efficiency was found 0.05, 0.04 and 0.03%, respectively. Germanium contents in different parts of lettuce cultivated with Ge $8.0mg\;kg^{-1}$ were $0.65mg\;kg^{-1}$ on inner leaf and $1.59mg\;kg^{-1}$ on outer leaf.

• Korean Journal of Remote Sensing
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• 제33권5_1호
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• pp.469-480
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• 2017

This study aims to understand the relationship between lineaments and epicenters in Geochang region, Gyungsangnam-do, South Korea. An instrumental observation of earthquakes has been started by Korea Meteorological Administration (KMA) since 1978 and there were 6 earthquakes with magnitude ranging 2 to 2.5 in Geochang region from 1978 to 2016. Lineaments were extracted from LANDSAT 8 satellite image and shaded relief map displayed in 3-dimension using Digital Elevation Model (DEM). Then, lineament density was statistically examined by hotspot analysis. Hexagonal grids were generated to perform the analysis because hexagonal pattern expresses lineaments with less discontinuity than square girds, and the size of the grid was selected to minimize a variance of lineament density. Since hotspot analysis measures the extent of clustering with Z score, Z scores computed with lineaments' frequency ($L_f$), length ($L_d$), and intersection ($L_t$) were used to find lineament clusters in the density map. Furthermore, the Z scores were extracted from the epicenters and examined to see the relevance of each density elements to epicenters. As a result, 15 among 18 densities,recorded as 3 elements in 6 epicenters, were higher than 1.65 which is 95% of the standard normal distribution. This indicates that epicenters coincide with high density area. Especially, $L_f$ and $L_t$ had a significant relationship with epicenter, being located in upper 95% of the standard normal distribution, except for one epicenter in $L_t$. This study can be used to identify potential seismic zones by improving the accuracy of expressing lineaments' spatial distribution and analyzing relationship between lineament density and epicenter. However, additional studies in wider study area with more epicenters are recommended to promote the results.

• The Korean Journal of Food And Nutrition
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• 제11권1호
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• pp.61-67
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• 1998

Effects of various jelly prepared with different concentrations of agar and sugars on overall acceptability of the peach jelly were investigated. The preparations of peach for experimental jelly were carried by the mixture of peach pulp and juice(MPJ), and the extract form peach(EP). The results were summarized as follows ; 1. The pH for MPJ and EP were 3.95 to 4/31, respectively, and the brix degree were 13.0% and 11.5%, respectively. 2. The jelly prepared with MPJ added 3% agar and 30% sugar were most effective in appearance, hardness, springiness and overall acceptability. The relation of samples(P<0.001) was found to be significant. On the other hand, the jelly prepared with EP was higher scored than that with MPJ in overall acceptability, but there was no significant differences between samples. 3. The Hunter values of L*, a* and b* were the highest in both the jelly prepared with MPJ and that with EP, added 2% agar and 10% sugar. However, the L*, a* and b* values of the jelly added MPJ were higher than those of the sample added EP. 4. Texture and color scores of both the jelly added EP became higher as the concentrations of agar and sugars increased and there was significant differences between samples. 5. The relation between springiness and overall acceptability, and L* value of the jelly added MPJ showed negative at P<0.05 and that between springiness and overall acceptability of the jelly added EP also showed negative.

• The korean journal of orthodontics
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• 제40권1호
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• pp.16-26
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• 2010

Objective: The purposes of this study were to evaluate the force and stress depending on the type, deflection and thickness of the materials and to evaluate the mechanical properties of thermoplastic materials after repeated loading. Methods: Four types of thermoplastic products were tested. Force until the deflections of 2.0 mm and the stress when the materials were restoring to its resting position were evaluated. The mechanical properties of thermoplastic materials evaluated after 5 repeated loading cycles. Results: The interaction was observed between the thickness and the deflection (p < 0.05) from the regression equation. Thickness and amount of deflection rather than products and materials showed the largest effect on force and stress. In all products, at least 159 gf of force was required for more than 1.0 mm deflection or when materials with 1.0 mm thickness were deflected. The stress recorded was more than 19 gf/$mm^2$. During repeated loading, each group showed significant difference on the force and the stress (p < 0.01), 10 - 17% reduction of force and 4 - 7% reduction of stress in average. Conclusions: Proper thickness of thermoplastic materials and deflection level of tooth movement should be decided for the physiologic tooth movement. Force decay after repeated loading should be considered for the efficient tooth movement.

• Korean journal of applied entomology
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• 제41권3호
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• pp.211-216
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• 2002

The present study was aimed to examine the effect of different host plants on the biological property of cotton caterpillar, outbreak pest of cucurbit vegetables. The feeding and oviposition preferences toward cucumber and pumpkin were greater than those toward watermelon, oriental melon, and melon. The periods of egg and larva fed on oriental melon, melon, and pumpkin were longer than those on watermelon and cucumber. The longest pupal period was 10.5 days from cucumber. The hatching rate, pupation rate, emergence rate, and survival rate were observed from different host plants. The hatching rate was the highest on cucumber (87.2%) and the lowest on melon (72.8%). The pupation rate on watermelon and oriental melon (90.0% and 89.1%, respectively) was higher than that on cucumber (62.0%). The emergence rate on cucumber and pumpkin (93.5% and 92.0%, respectively) was higher than that on oriental melon (78.7%). The survival rate from hatching to emergence on watermelon (76.0%) was the highest, and the lowest on cucumber (50.0%). The adult period on melon (21.0 days) was the longest, and the shortest on cucumber (15.5 days) among 5 host plants. Average number of eggs per female on cucumber (281.8 eggs) was the highest, and the least on oriental melon (96.6 eggs). The survivorship on cucumber was the longest (30 days), and the shortest on pumpkin (17 days). The preoviposition period on oriental melon and melon (3.4 days) was longer than that on watermelon (2.1 days) and mean generation time in day (T) on melon was the longest (47.2 days) though they were not significant. The net reproductive rate per generation (R$_{o}$) on cucumber, 191.3, was the highest and the highest intrinsic rate of natural increase (r$_{m}$) was observed from cucumber as 0.127. All these results suggest that the growth ana reproduction of cotton caterpillar varies depending upon the kind of host plants. The analysis of the life table revealed that cucumber and pumpkin were the favorable host plants of cotton caterpillar.

• Journal of the Korean earth science society
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• 제39권3호
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• pp.241-249
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• 2018

As the international trade increases, vessel traffics around the Korean Peninsula are also increasing. Maritime accidents hence take place more frequently in the southern coast of Korea where many big and small ports are located. Accidents involving ship collision and sinking result in a substantial human and material damage as well as the marine environmental pollution. Therefore, it is necessary to locate the ships quickly when such accidents occur. In this study, we suggest a new ship detection index by comparing and analyzing the reflectivity of each channel of the Korea MultiPurpose SATellite-2 (KOMPSAT-2) images of the area around the Gwangyang Bay. A threshold value of 0.1 is set based on a histogram analysis, and all vessels are detected when compared with RGB composite images. After selecting a relatively large ship as a representative sample, the distribution of spatial reflectivity around the ship is studied. Uniform shadows are detected on the northwest side of the vessel. This indicates that the sun is in the southeast, the azimuth of the actual satellite image is $144.80^{\circ}$, and the azimuth angle of the sun can be estimated using the shadow position. The reflectivity of the shadows is 0.005 lower than the surrounding sea and ship. The shadow height varies with the position of the bow and the stern, perhaps due to the relative heights of the ship deck and the structure. The results of this study can help search technology for missing vessels using optical satellite images in the event of a marine accident around the Korean Peninsula.

• Korean journal of applied entomology
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• 제53권4호
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• pp.339-346
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• 2014

To control populations of the chestnut weevil, Curculio sikkimensis Heller, the effects of various immersion temperatures and times on the chestnut weevil were tested. The effects of immersion treatments on chestnut fruits were also analyzed. The mortality levels of C. sikkimensis larvae were evaluated at various temperatures ($30^{\circ}C$, $35^{\circ}C$, $40^{\circ}C$, $45^{\circ}C$, and $50^{\circ}C$) and time intervals (1, 2, 3, 5, 7, 10, 15, 22, and 24 h). Changes in the chestnut fruit due to the immersion treatment were measured in terms of color (lightness, redness, and yellowness), physiological effects (germination rate and decay rate), hardness, and change in constituent properties (moisture content, free sugar content, and tannin content). Mortality levels of C. sikkimensis larvae after immersion treatment at $30^{\circ}C$ were over 70% and 100% after 2 h and 7 h, respectively. Color (lightness, redness, and yellowness) of the chestnut fruits was not significantly different at $30^{\circ}C$ and $35^{\circ}C;$ however, the color was affected at temperatures over $40^{\circ}C$. The germination rate of the fruit was not affected by the immersion treatments, but the decay rate at $40^{\circ}C$ increased with an increase in immersion time. The hardness of the fruits decreased with an increase in immersion times and temperatures. These results can be used in the future for developing methods for the control of chestnut weevil populations.

• Korean Journal of Environmental Biology
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• 제34권4호
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• pp.320-328
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• 2016

This study was conducted to provide important basic information about effective management of the marine environment at major inflow streams in Lake Andong and Lake Imha. The investigation was conducted 8 times from May, 2015 (AD1, AD2, IH1, IH2) to September, 2016 (AD3, AD4, IH3, IH4), and 8 surveyed sites were selected at Lake Andong (4 sites) and Lake Imha (4 sites). The inquiry identified 114 species, $59,913.7inds.\;m^{-2}$ in Lake Andong and 112 species, $39,038.4inds.\;m^{-2}$ in Lake Imha. The results indicate that the number of species and individuals in Lake Andong is more than that in Lake Imha, because Lake Andong has a variety of riparian vegetation and a richness of organic materials. Community analysis at Lake Imha revealed a dominant index of 0.57 (${\pm}0.18$), a diversity index of 2.87 (${\pm}0.31$), an evenness index of 0.73 (${\pm}0.04$), and a richness index of 4.17 (${\pm}0.71$). The results of functional feeding group analysis showed that a high proportion of species and individuals are gathering collectors. The results of functional habitat group analysis showed that a high proportion of species and individuals are clingers. The result of a physico-chemical water assay and dissolved oxygen and electric conductivity tests revealed that these measures increased when the water temperature decreased. The result of Pearson's correlation analysis by biological factors and physico-chemical factors showed that species and electric conductivity are highly correlated with one another. Major inflow streams of Lake Andong and Lake Imha were exposed to various point pollution sources and non-point pollution sources. This implies a necessity for continuous monitoring of the aquatic ecosystems in order to effect systematic water quality management of Lake Andong and Lake Imha.

• Food Science of Animal Resources
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• 제31권1호
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• pp.86-91
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• 2011

This experiment was conducted to investigate the effects of dietary supplementation with lutein-containing materials on meat quality and lutein accumulation in broiler tissue. Broilers were subjected to one of the following treatments: C, basal diet (BD); T1, BD + 2.223% lutein from spinach extracted by ethanol fermentation; T2, BD + 2% radish green powder; T3, BD + 0.61% spinach powder; and T4, BD + 1.83% spinach powder. The weight gain, feed intake, and feed conversion did not differ among treatments. An evaluation of the color of the chicken breast meat revealed that the CIE $L^*$ value of the control was significantly (p<0.05) lower than that of the other treatments, whereas T4 had a significantly (p<0.05) lower CIE $a^*$ value and a higher (p<0.05) CIE $b^*$ value than the other treatments. The lipid oxidation (thiobarbituric acid reaction substances, TBARS) value was not significant among treatments. The results of a high performance liquid chromatography analysis revealed that the lutein peak was present only in the T4 liver tissue. These results showed that spinach powder (T4) affected meat color (CIE $a^*$ and $b^*$) however, TBARS and lutein accumulation were not affected.

• Radiation Oncology Journal
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• 제21권2호
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• pp.149-157
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• 2003

Purpose: The purpose of this study was to determine if there were prognostic differences between BRCA related and BRCA non-related Korean patients with early-onset breast carcinomas. Materials and Methods: Sixty women who had developed breast cancers before the age of 40, and who were treated at the Soonchunhyang University Hospital, were studied independently of their family histories. The age range was 18 to 40 with a median of 34.5 years. Lymphocyte specimens from peripheral blood were studied for the heterozygous mutations of BRCA1 and BRCA2 using direct sequencing methods. Immunohistochemistry was peformed on the paraffin-embedded tissue blocks that were available. Results: Eleven deleterious mutations (18.3%, 6 in BRCA1 and 5 in BRCA2) and 7 missense mutations of unknown significance (11.7%), were found among the 60 patients. More than half of the mutation were novel, and were not reported in the database. Most of the BRCA-associated patients had no history of breast cancer. No treatment related failures were observed in the BRCA carriers, with the exception of one patient that had experienced a new primary tumor of the contralateral breast. The seven year relapse free survival rate were 50 and 79% In the BRCA carrier and BRCA negative patients, respectively. Although the expression of estrogen and progesterone receptors were less common, and histological features more aggressive, in the BRCA associated tumors, the outcome of the patients with BRCA mutations was not poorer than that on the patients without deleterious mutations. Conclusion.: Despite the BRCA mutation carriers having adverse prognostic features, the recurrence rate was relatively lower than that in the BRCA non-carrying Korean patients wi4h early-onset breast carcinomas. In addition, although the prevalence of the BRCA mutation in Korean patients was higher than that in white patients, the penetrance of the cancer seemed to be relatively low in Korean women carrying BRCA mutations. A large population based study of the BRCA mutation, with a long-term follow-up of the study patients will be required to confirm these results.