• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.3
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• pp.409-415
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• 2022

The length of the acceleration lane in the area of entrance terminals is calculated based on 13 PS/ton horsepower of a cargo truck in Korea, so it is generally overestimated compared with the capacity of most vehicles traveling on an entrance ramp. Most drivers have, therefore, an indiscreet tendency to enter the main lane in all sections of an acceleration lane, which affects the traffic flow of the main lane. Because of this tendency, measures are required to minimize the impact on traffic flow of the main lane. The operating speed, rate of entrance, and traffic volume for each vehicle were investigated at the entrance terminals of the interchanges (ICs) of Yangji IC, Suseok IC, Yongin IC, and Osan IC, and the level of improvement in traffic flow was analyzed via VISSIM simulation. From the VISSIM simulation analysis, 74.0 % of the total vehicles traveled over the specified speed from the nose point where drivers would be able to recognize the traffic condition of the main carriageway, or the point at which there is a simplification of the curve section. In addition, 88.6 % of the vehicles entered the main carriageway up to 0.8 points compared with the entire length of the acceleration lane. It was subsequently found that an improvement of average speed in the main carriageway and at the entrance ramp can be achieved from 60.1 km/h to 68.5 km/h by intentionally limiting the entrance point onto the main carriageway up to 0.265 points of the entrance ramp.

• Journal of Marine Life Science
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• v.1 no.1
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• pp.1-7
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• 2016

In order to assess seasonal and geographical characteristics of pollutant Escherichia coli, we investigated its distribution in Nakdong River mouth and Busan coastal water from February 2013 to November 2015. The coastal area was divided into five different zones (I-V) based on the pollutant level and geographical characteristics. During the study periods, water temperature and salinity varied from 7.50 to 27.64℃ and 16.82 to 34.82 psu, respectively. The annual water temperature variation was characterized in temperate zone. The salinity was significantly (p<0.05) decreased in zone IV and zone III after heavy rain during summer season in 2014, resulting led to elevated E. coli biomass. The highest colony formation of E. coli was recorded at 6,000 cfu l^-1 during autumn at station 1 (zone I). On the other hands, during all seasons of 2015, E. coli abundances were kept to be low level in zone III. The E. coli was not significantly (p>0.05) correlated with water temperature. However, the salinity was significantly (r=-0.53, p<0.05) correlated with the E. coli, implying that salinity plays a crucial role in the proliferation of E. coli. Consequently, E. coli in western Busan coastal water might have been significantly promoted by pollutant sources from Nakdong Rive discharge during the spring and summer rainy seasons depending on annual rainfall variations. On the other hands, E. coli in station 1 (i.e., Suyeong Bay) was obviously high due to influences of discharge water from municipal wastewater treatment plant. However, there was no clear seasonality of E. coli.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.193-200
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• 2023

This study evaluate the quality characteristics and antioxidative properties of acorn mook containing seoritae powder(0%, 2%, 4%, 6%). Among them the results of moisture content, Hunter color system, Texture, and antioxidant activity by making a section different Acorn Mook. The moisture content of samples 70.83%~81.77%, as the Seoritae powder Level in the formulation increased. As the Seoritae powder Level in the formulation increased, L-value of samples decreased, a-value of samples 7.29~7.79 increased and b-value decreased. According to the texture evaluation results, as the Seoritae powder level in the formulation significant decreased, the hardness, adhesivness, chewiness and cohesiveness, chewiness of acorn mook decreased. Seoritae powder level in the formulation increased Total phenol contents increased, Total flavonoid contents, DPPH free radical scavenging activity and ABTS radical scavenging activity of acorn mook decreased. The sensory results, the 2% samples received high taste, color, elasticity, chewiness, overall acceptability scores. In addition the 4% added samples of Seoritae powder showed a good overall evaluation compared to the control samples, so if acorn mook is manufactured by adding 2%~4% of Seoritae powder, it is thought that there is a possibility of commercialization of Seoritae acorn mook. We have the above results adding Seoritae powder to make a traditional food mook will help to use it as basic data for making acorn mook with excellent antioxidant activity.

• Korean Journal of Plant Resources
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• v.37 no.1
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• pp.22-34
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• 2024

Recently, in several regions of Korea, we discovered the occurrence of Sagina micropetala Rauschert and S. procumbens L. All the plants of the genus Sagina growing in Korea are 5-merous and belong to the sect. Spergella. However, the two taxa we discovered belong to the sect. Saginella and are 4-merous. In addition, morphological characteristics such as sepals during the fruiting season and seeds were significantly different from those of species of the genus Sagina that occur in Korea. To clearly identify these species, we compared and observed their primary morphological characteristics using illustrated books and literature. Morphologically, S. micropetala exhibits the following traits: pubescence along the leaf margin, horizontally spreading sepals with red margins, and convex protrusions on the seed surface. In contrast, S. procumbens can be distinguished by its pedicels, which are curved during the flowering season and erect during the fruiting season. This plant also has broadly ovate sepals with white or yellowish-green margins, and flat seed surface protrusions. In terms of molecular analyses, 19 samples of Sagina were divided into two clades (S. micropetala and S. procumbens), confirming the taxonomic identity of the Sagina spp.

• The Journal of the Petrological Society of Korea
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• v.26 no.1
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• pp.45-54
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• 2017

The characteristics of the rock cleavage in Jurassic Geochang granite were analysed using the distribution of microcrack lengths and spacings. The phases of distribution of the above lengths and spacings were derived from the enlarged photomicrographs(${\times}6.7$) of the thin section. First, the length and spacing-cumulative diagrams for the six directions of rock cleavages were arranged in increasing order($H2{\rightarrow}R1$) on the density(${\rho}$) of microcrack length. The various parameters were extracted through the combination of the above two types of diagrams. The discrimination factors representing the three quarrying planes and three rock cleavages were acquired through the mutual contrast between the values of parameters. The analysis results of the research are summarized as follows. The evaluation for the six directions of rock cleavages was performed using the parameters such as (1) intersection angle(${\alpha}-{\beta}$) and (2) exponent difference(${\lambda}_S-{\lambda}_L$) between two exponential straight lines related to spacing(${\alpha}$, ${\lambda}_S$) and length(${\beta}$, ${\lambda}_L$). The values of parameters(1 and 2) are in order of H(hardway, (H1 + H2)/2) < G(grain, (G1 + G2)/2) < R(rift, (R1 + R2)/2). On the contrary, the values of the above two parameters for three planes are in order of R < G < H. Meanwhile, the direction of convergence between two exponential straight lines was derived. The above direction is compliant to arrangement of the line os' centering around the line ol. The above two lines converge in the direction of the Y-axis when the line ol and line os' occupy the upper region on the left and the lower region on the right, respectively(R-type). On the contrary, the above two lines converge in the direction of the X-axis when the order of arrangement between line ol and line os' is reversed(H-type). Especially, the positive(+) or negative(-) value of intersection angle(${\alpha}-{\beta}$) is determined by the arrangement of two vertical lines. This type of correlation analysis is useful for evaluating the relative strength of rock cleavage and discriminating three quarrying planes.

• Korean Journal of Plant Taxonomy
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• v.32 no.3
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• pp.339-362
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• 2002

Pollen morphology of 13 species of Korean Euphorbia was re-examined by means of LM and SEM. Taxonomic evaluation of palynological characters and relationships among taxa were also discussed based on the analysis of polar length, equatorial diameter, aperture size and exine thickness. Korean Euphorbia species were classified into three groups based on the mean size of polar length (P) and equatorial diameter (E) as follows:Group 1. sect. Tulocarpa and Tithymalus of subgenus Esula; $(P){\times}(E)=(54.88-67.17{\mu}m){\times}(44.30-64.75{\mu}m)$, Group 2. sect. Esula and Helioscpiae of subgenus Esula; $(P){\times}(E)=(39.98-47.24{\mu}m){\times}(36.07-38.83{\mu}m)$, Group 3. sect. Chamaesyce and Hypericifoliae of subgenus Chamaesyce; $(P){\times}(E)=(30.32-32.51{\mu}m){\times}(21.71-26.23{\mu}m)$. Various features of surface sculpturing were also grouped into 8 types by the characteristics of perporation size and distance of perporations as well as connection state of it. Pollen size and surface sculpturing were comparatively available in the levels of subgenus and section. Especially subgenus Chamaesyce was distinctly different from subgenus Esula by having compactly distributed perporations on exine surface as well as its small size of pollen grains. Because of the great variations in pollen size and the occurrence of various types of surface sculpturing according to the local poulations of each species, it was evaluated that they were unsuitable in classifying each species of Euphorbia. But such cases, that is, E. hylonoma being more familiar with E. ebracteolata than E. Pallasii, and E. pekinensis and E. fauriei as well as E. pallasii being strongly related with each other based on the similarity of surface sculpturing, reflected its usefulness in the classification of some Euphorbia species.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.309-315
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• 2019

Cervical cancer is the fourth most common malignant neoplasm in women worldwide. Most cases of cervical cancer are caused by an infection by the human papillomavirus. Molecular diagnostic methods have emerged to detect the HPV for sensitivity, specificity, and objectivity. In particular, real-time PCR has been introduced to acquire a more sensitive target DNA or RNA. RNA extraction and complementary DNA synthesis are proceeded before performing real-time PCR targeting RNA. To identify an adequate and sensitive cDNA synthesis kit, this study evaluated the two commonly used kits for cDNA synthesis. The results show that the $R^2$ and efficiency (%) of the two cDNA synthesis kits were similar in the cervical cancer cell lines. On the other hand, the Takara kit compared to Invitrogen kit showed P<0.001 in the $10^2$ and $10^3$ SiHa cell count. The Takara kit compared to the Invitrogen kit showed P<0.001 in the $10^1$ and $10^2$ HeLa cell count. Furthermore, 8, 4, 2, 1, and 0.5 ml of forty exfoliated cell samples were used to compare the cDNA synthesis kits. The Takara kit compared to the Invitrogen kit showed P<0.01 in 8, 4, and 1 ml and P<0.05 in 0.5 mL. The study was performed to identify the most appropriate cDNA synthesis kit and suggests that a cDNA synthesis kit could affect the real-time PCR results.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.4
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• pp.247-265
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• 2008

Objectives: Many types of liver diseases can damage regenerative potential of mature hepatocytes, hepatic progenitor cells or oval cells. In such cases, a stem cell-based therapy can be an alternative therapeutic option. We examined whether human amnion-derived mesenchymal stem cells (HAM) and human umbilical cord-derived stem cells (HUC) could differentiate into hepatocyte-like cells as therapeutic cells for the liver diseases. Methods: HAM and HUC were isolated from the amnion and umbilical cord of the volunteers after a caesarean section with informed consent. In order to differentiate these cells into hepatocyte-like cells, cells were cultivated in hepatogenic medium using culture plates coated with fibronectin. Effects of hepatocyte growth factor, L-ascorbic acid 2-phosphate, insulin premixture fibroblast growth gactor 4, dimethylsulfoxide, oncostatin M and/or dexamethasone were examined on the hepatic differentiation. After differentiation, the cells were analyzed by RT-PCR, immunocytochemistry, immunoblotting, albumin ELISA, urea assay and periodic acid-schiffs staining. Results: Initial fibroblast-like appearance of HAM and HUC changed to a round shape during culture in the hepatogenic medium. However, in all hepatogenic conditions examined, HUC secreted more amounts of albumin or urea into medium than HAM. Expression of some of hepatocyte-specific genes increased and expression of new genes were observed in HUC following cultivation in hepatogenic medium. Results of immunocytochemistry and immunoblotting analyses demonstrated that HUC secreted albumin into the culture medium. PAS staining further demonstrated that HUC could store glycogen inside of the cells. Conclusions: Both HUC and HAM could differentiate into albumin-secreting, hepatocyte-like cells. Under the same hepatogenic conditions examined, HUC more efficiently differentiated into hepatocyte-like cells compared with the HAM. The results suggest that HUC and HAM could be used as sources of stem cells for the cell-based therapeutics such as in liver diseases.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.506-521
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• 2007

Statement of problem: The cumulative success rate of wide implant is still controversial. Some previous reports have shown high success rate, and some other reports shown high failure rate. Purpose: The aim of this study was to analyze, and compare the biomechanics in wide implant system embeded in different width of crestal bone under different occlusal forces by finite element approach. Material and methods: Three-dimensional finite element models were created based on tracing of CT image of second premolar section of mandible with one implant embedded. One standard model (6mm-crestal bone width, 4.0mm implant diameter central position) was created. Varied crestal dimension(4, 6, 8 mm), different diameter of implants(3.3, 4.0, 5.5, 6.0mm), and buccal position implant models were generated. A 100-N vertical(L1) and 30 degree oblique load from lingual(L2) and buccal(L3) direction were applied to the occlusal surface of the crown. The analysis was performed for each load by means of the ANSYS V.9.0 program. Conclusion: 1. In all cases, maximum equivalent stress that applied $30^{\circ}$ oblique load around the alveolar bone crest was larger than that of the vertical load. Especially the equivalent stress that loaded obliquely in buccal side was larger. 2. In study of implant fixture diameter, stress around alveolar bone was decreased with the increase of implant diameter. In the vertical load, as the diameter of implant increased the equivalent stress decreased, but equivalent stress increased in case of the wide implant that have a little cortical bone in the buccal side. In the lateral oblique loading condition, the diameter of implant increased the equivalent stress decreased, but in the buccal oblique load, there was not significant difference between the 5.5mm and 6.0mm as the wide diameter implant. 3. In study of alveolar bone width, equivalent stress was decreased with the increase of alveolar bone width. In the vertical and oblique loading condition, the width of alveolar bone increased 6.0mm the equivalent stress decreased. But in the oblique loading condition, there was not a difference equivalent stress at more than 6.0mm of alveolar bone width. 4. In study of insertion position of implant fixture, even though the insertion position of implant fixture move there was not a difference equivalent stress, but in the case of little cortical bone in the buccal side, value of the equivalent stress was most unfavorable. 5. In all cases, it showed high stress around the top of fixture that contact cortical bone, but there was not a portion on the bottom of fixture that concentrate highly stress and play the role of stress dispersion. These results demonstrated that obtaining the more contact from the bucco-lingual cortical bone by installing wide diameter implant plays an important role in biomechanics.

• Korean Journal of Environment and Ecology
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• v.23 no.5
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• pp.431-438
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• 2009

The main purpose of this research is to prepare and provide basic materials for the propagational strategy of eelgrass by investigating on the morphological adaptation of Korean Zostera marina to ocean currents. An eelgrass plant mainly consists of rhizome, leaf sheath, leaves and roots. The rhizome is the horizontal stem of the plant that serves as the backbone from which the leaves and roots emerge. The leaf sheath is the bundle at the base of the leaves that holds the leaves together, protecting the meristem, the primary growth point of the shoot. Leaves originate from a meristem which is protected by a sheath at the actively growing end of the rhizome. As the shoot grows, the rhizome elongates, moving across or within the sediment, forming roots as it progresses. The aggregated leaves from the leaf sheath are found to have two cell layers on one side and multiple layers of airy tissues called aerenchyma on the other. The aerenchyma tissues are developed in multi-layered cell structures surrounding the veins which are formed in the leaf sheath. Generative shoots are made of rhizomes, which are circular or ovoidal, stem, and spathe and spadix. The transverse section of rhizome and the stem and central floral axis is found to be circular, ovoid and in the shape of convex respectively, and the vascular bundle, which is a part of transport system, has one large tube in the center and two small tubes on both sides. The layers of collenchyma cells numbered from 12 to 15 in the stem, and from 7 to 12 in the rhizome. The seed coat is composed of sclereids, small bundles of sclerenchyma tissues, which prevent the influx of sea water from the outside and help endure the environmental stress. In conclusion, alternative multi-layer structure in circular, convex type aggregated leaf base are interpreted to morphological adaption as doing tolerable elastic structure through movement of seawater. The generative shoots develop long slim stem and branches in circular or ovoidal shapes to minimize the adverse impacts of sea current, which can be interpreted as the plant's morphological adaptation to its environment.