• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.2
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• pp.94-99
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• 2004

This study was conducted to determine the effect of salinity on the growth and development of Korean ginseng (Panax ginseng C.A.Meyer) and to evaluate the inorganic ion content in Korean ginseng with different general complete fertilizer (GCF) and NaCI concentrations at two growth stages. The stem height of Korean ginseng treated with different GCF and NaCI concentrations decreased at the higher EC (2.0 dS m$^{-1}$ ), but there were no significant difference in the stem diameter, the leaf length, and the leaf width among different treatments. The root growth increased with the supply of GCF. Especially, the root growth was facilitated two times at 3.0 dS $\textrm{m}^{-1}$ as compared to control. But the root growth more sharply decreased with NaCI treatment than GCF. The $\textrm{K}^{+}$ and $\textrm{Mg}^{2+}$ content in leaves and roots increased with GCF at the early growth stage. At the late growth stage, the $\textrm{K}^{+}$ content in leaves decreased but the $\textrm{Ca}^{2+}$ and $\textrm{Mg}^{2+}$ content increased. The $\textrm{Ca}^{2+}$ and $\textrm{Mg}^{2+}$ content in roots increased but the $\textrm{K}^{+}$ content decreased. The $\textrm{Na}^{+}$ content in Korean ginseng increased sharply with NaCl treatment. The $\textrm{NO}_3^{-}$ content in leaves and $\textrm{NH}_4^{+}$ content in leaves and roots increased as GCF concentration increased. The $\textrm{NO}_3^{-}$ content in leaves, stems, and roots at the late growth stage decreased as NaCl concentration increased. The $\textrm{NH}_4^{+}$ content in leaves and roots decreased significantly at the early growth stage, but it decreased significantly in leaves and stems at the late growth stage. The root activity of Korean ginseng increased with GCF, but decreased as the EC increased with NaCl. The water potential of leaves with GCF showed no significant difference compare to control, but the water potential of leaves treated with NaCl decreased as EC increased.

• Journal of Animal Science and Technology
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• v.50 no.3
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• pp.285-292
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• 2008

Data were taken from the dairy herd improve- ment program from the year 2000, composed of 10,929 first lactation cows consisting of 290,144 test-day records and 37,723 udder type records. The objective of the study was to estimate genetic and phenotypic correlation between fore udder attachment, rear udder height, rear udder width, udder cleft, udder depth, and somatic cell score (SCS) and to calculate heritability of udder depth, front teat length and SCS in Holstein cattle in Korea. The variance component estima- tion using test day model was determined by a derivative-free algorithm-restricted maximum likeli- hood(DF-REML) analysis method. Generally phenotypic correlations were very low between udder traits and lactation SCS which varied from －0.03 to －0.06. Heritability of all type traits and SCS was smaller than 0.12. The results of this study would be applicable to SCS using linear genetic evaluation for future studies.

• Tunnel and Underground Space
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• v.26 no.6
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• pp.455-465
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• 2016

The collapse of underground mine development void for mineral resources can cause the subsidence of ground surface. In order to prevent the subsidence of ground, data such as maps or pictures of past mining site is important information for current mine reclamation works. In particular, mine subsidence management was based on mining maps and pictures. The process of the mining area surveys, safety evaluation, and ground reinforcement are normally possible with information such as maps and pictures in past mining. During the Japanese colonial period and 1960's, a lot of mines were developed in Korea indiscriminately. However, mining information at that time is limited to use. In the future, mining information will become even more rare. MIRECO intends to establish a realistic alternative solution. In this study, the basic numerical information of developed mine tunnels in Korea is statistically reviewed, and advanced underground cavity measuring technology was studied. 4,473 mine tunnel opening data of 1,784 abandoned mines in korea were collected and sorted. As a result of the analysis, the average value of small mine tunnel openings in Korea was 1.982 m in height and 1.959 m in width. The mean value of shape factor was analyzed as 0.485. The summary of these numerical mine data will be helpful for understanding and researching Korean abandoned mines. Therefore, the development of measurement technology for abandoned mine cavities and tunnels is expected to facilitate more effective mine subsidence management works in Korea.

• FLOWER RESEARCH JOURNAL
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• v.17 no.1
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• pp.15-22
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• 2009

This study was conducted to examine characteristics of rhizome growth and flowering of white lotus (Nelumbo nucifera) plant in Muan Hoesan-lake for collecting the basic data on the cultivation and the flowering which is growing in Muan Hoesan-lake of Jeonnam province in Korea. We have planted from the seeds and the enlarged rhizomes of the white lotus which were planted in the plastic containers on April 20 and May 4, 2008, and cultivated under rain shelter condition. Rhizome growth pattern and the flowering characteristics of the white lotus were examined on September 4, 2008. Main rhizomes of the white lotus propagated by the seeds and the enlarged rhizomes were branched by 10% and 15%, respectively. Numbers of nodes in the bloomed and non-bloomed rhizomes of the white lotus were over 14 and below 11, respectively. Flower was not observed in the white lotus when propagated with seeds, however, flowers came out up to 80% by the enlarged rhizomes. First flowers were bloomed from the late July and to the early August, and the number of flowers were 4.0~4.4. The first flower stalks without branching of the main rhizome were emerged in 8.8th node, however, that with branching were 8.0th node. Time to flowering from the emergence of flower stalk on the above-ground parts were required 16 days. White flowers from the lotus were 15.3 cm in height and 28.2 cm in width, their longevity was 3.3 days and the averaged flower fresh weight was 29.2 g. The results conclude that optimum number of nodes on the main rhizomes for blooming the white lotus flowers should be over 8 nodes before the rhizome enlargement.

• Journal of agriculture & life science
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• v.45 no.3
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• pp.43-51
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• 2011

This project was conducted to measure actual temperature, relative humidity (RH), and light intensity at different apartment floors and to suggest suitable indoor plants by investigating morphological changes of Treophelosparmum asiatioum and Fittonia verchaffeltii var. argyroneura as affected by light intensity. Temperature and RH in apartment verandas were measured in three different (2nd, 9th, and 16th) floors on three different buildings for 30 days seasonally. The light intensity, temperature, and RH were recorded outside (parking area) and inside apartment verandas for 24 hours on a selected sunny summer day (between Aug. 19 and Sept. 14, 2008). Based on the first study, we investigated effect of simulated light intensity (40, 70, 100, and $600{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) on changes in growth and development of T. asiatioum and F. verchaffeltii var. argyroneurain growth chambers. However, daily mean light intensity of 2nd, 9th, and 16th floors was different each other as it was about 40, 70, and $100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. In the growth chamber experiment, plant height, internode length, and leaf length and width were not affected significantly by light intensity, but changes in leaf color were apparent in the new leaves with the increasing light intensity. The results suggest that T. asiatioum could be best fit to high, and F. verchaffeltii var. argyroneura to lower floor verandas, considering their aesthetic values.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.72-72
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• 2019

This study compared the growth characteristics of A. gigas according to the transplanting season, in the cultivation located in Yeongju, Gyeongsangbuk-do, transplanted in the autumn and spring. As a result of that the plant survival rate were observed the highest autumn transplanting (9.4%; autumn-92.2%, spring-82.8%) and bolting rate were observed lowest spring transplanting (7.1%; autumn-37.3%, spring-30.2%). Growth characteristics (height, leaf length and width, stem diameter) were observed the highest autumn transplanting in June and highest spring transplanting in August. The early growth is high growth due to long rooting time in autumn transplanting, but the difference in the ground growth between the two experiments was insignificant when the main growth period was from June to August. Further analysis of the growth characteristics and marker components of roots of A. gigas can be used to determine the optimal planting time and the establishment of high quality cultivation technology.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.822-831
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• 2021

Although programs have been developed to evaluate the risk of dragging anchors, it is practically difficult for VTS(vessel traffic service) operators to calculate and evaluate these risks by obtaining input factors from anchored ships. Therefore, in this study, the gross tonnage (GT) that could be easily obtained from the ship by the VTS operators was set as an independent variable, and linear and nonlinear regression analyses were performed using the input factors as the dependent variables. From comparing the fit of the polynomial model (linear) and power series model (nonlinear), the power series model was evaluated to be more suitable for all input factors in the case of container ships and bulk carriers. However, in the case of tanker ships, the power supply model was suitable for the LBP(length between perpendiculars), width, and draft, and the polynomial model was evaluated to be more suitable for the front wind pressure area, weight of the anchor, equipment number, and height of the hawse pipe from the bottom of the ship. In addition, all other dependent variables, except for the front wind pressure area factor of the tanker ship, showed high degrees of fit with a coefficient of determination (R-squared value) of 0.7 or more. Therefore, among the input factors of the dragging anchor risk assessment program, all factors except the external force, seabed quality, water depth, and amount of anchor chain let out are automatically applied by the regression analysis model formula when only the GT of the ship is provided.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.19 no.2
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• pp.8-19
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• 2023

Hydronic heated road pavement (HHP) systems have well studied and documented by many researchers. However, most of the systems run on asphalt, only a few are tested with concrete, and there rarely is a comparison between those two common road materials in their heating and cooling performance. The aim of this study is to investigate the thermal performance of the HHP, such as heat dissipation performance in winter season while focusing on the surface temperature of the concrete and asphalt pavement. For preliminary study a small-scale experimental system was designed and installed to evaluate the heat transfer characteristics of the HHP in the test field. The system consists of concrete and asphalt slabs made of 1 m in width, 1 m in length, and 0.25 m in height. In two slabs, circulating water piping was embedded at a depth of 0.12 m at intervals of 0.16 m. Heating performance in winter season was tested with different inlet temperatures of 25℃, 30℃, 35℃ and 40℃ during the entire measurement period. The results indicated that concrete's heating performance is better than that of asphalt, showing higher surface temperatures for the whole experiment cases. However, the surface temperature of both concrete and asphalt pavement slabs remained above 0℃ for all experimental conditions. The heat dissipation performance of concrete and asphalt pavements was analyzed, and the heat dissipation of concrete pavement was greater than that of asphalt. In addition, the higher the set temperature of the circulating water, the higher the heat dissipation. On the other hand, the concrete pavement clearly showed a decrease in heat dissipation as the circulating water set temperature decreased, but the decrease was relatively small for the asphalt pavement. Based on this experiment, it is considered that a circulating water temperature of 20℃ or less is sufficient to prevent road ice. However, this needs to be verified by further experiments or computational fluid dynamic (CFD) analysis.

• Journal of Periodontal and Implant Science
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• v.53 no.4
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• pp.306-317
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• 2023

Purpose: Biphasic calcium phosphate (BCP), a widely used biomaterial for bone regeneration, contains synthetic hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP), the ratio of which can be adjusted to modulate the rate of degradation. The aim of this study was to evaluate the clinical and radiographic benefits of reconstructing peri-implant bone defects with a newly developed BCP consisting of 60% β-TCP and 40% HA compared to demineralized bovine bone mineral (DBBM). Methods: This prospective, multicenter, parallel, single-blind randomized controlled trial was conducted at the periodontology departments of 3 different dental hospitals. Changes in clinical (defect width and height) and radiographic (augmented horizontal bone thickness) parameters were measured between implant surgery with guided bone regeneration (GBR) and re-entry surgery. Postoperative discomfort (severity and duration of pain and swelling) and early soft-tissue wound healing (dehiscence and inflammation) were also assessed. Data were compared between the BCP (test) and DBBM (control) groups using the independent t-test and the χ² test. Results: Of the 53 cases included, 27 were in the test group and 26 were in the control group. After a healing period of 18 weeks, the full and mean resolution of buccal dehiscence defects were 59.3% (n=16) and 71.3% in the test group and 42.3% (n=11) and 57.9% in the control group, respectively. There were no significant differences between the groups in terms of the change in mean horizontal bone augmentation (test group: -0.50±0.66 mm vs. control groups: -0.66±0.83 mm, P=0.133), postoperative discomfort, or early wound healing. No adverse or fatal complications occurred in either group. Conclusions: The GBR procedure with the newly developed BCP showed favorable clinical, radiographic, postoperative discomfort-related, and early wound healing outcomes for peri-implant dehiscence defects that were similar to those for DBBM.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.3
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• pp.287-301
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• 2009

The novel cut-and-cover tunnel construction method using rib-reinforced pre-cast arch segments has been recently developed and applied for practice to secure a structural stability of high covering and wide width section tunnels. Cut-and-cover tunnels are usually damaged by the seismic behavior of backfill grounds in case of a low covering condition. Seismic analyses are performed in this study to characterize the dynamic behavior of rib-reinforced pre-cast arch cut-and-cover tunnels. Seismic analyzes for 2 lane cast-in-place and rib-reinforced pre-cast arch cut-and-cover tunnels are carried out by using the commercial FDM program (FLAC2D) considering various field conditions such as the covering height embankment slope and excavation slope. It can be concluded that the amplification of seismic wave is reduced due to an increase in the structural stiffness induced by rib-reinforcement. The results show that the rib-reinforced pre-cast arch cut-and-cover tunnels are more effective against the seismic loading, compared to the cast-in-place cut-and-cover tunnels.