• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.439-445
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• 2014

In this study, we developed a dynamic stand yield model to estimate the baseline carbon stock, which is essentially required for a forest carbon offset project based on forest management. For developing the yield model, the data was acquired from the databases of the $5^{th}$ National Forest Inventory. The model was validated by comparing its estimations with field measurements that were conducted from 4 study sites (14 plots with thinning treatments) located in Hong-chun, Hoeng-sung, Yang-yang Daechi and Yang-yang Jungja. The difference between the estimations and the field measurements was less than 5%. Using the dynamic stand yield model, we estimated the changes in stand yield volume and carbon stocks for each species according to the baseline scenarios. As the results, we found that baseline carbon stock was the highest at Quercus acutissima stand (83.01tC/ha), while the lowest at Pinus rigida stand (32.17tC/ha) and Pinus densiflora stand of central region (39.09tC/ha). Hence, a project provider could get more carbon emission credits from an improved forest management project when considering the project with Pinus rigida stand or Pinus densiflora stand (central region). The baseline carbon stock and the dynamic stand yield model developed from this study would be useful for designing carbon offset projects based on improved forest management.

• Journal of Embryo Transfer
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• v.16 no.3
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• pp.173-182
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• 2001

The present study was carried out to examine the effect of superoxide dismutase (SOD) on in vitro maturation (IVM) of porcine follicular oocytes and oxygen concentration with SOD on in vitro development (IVD) of porcine IVM/IVF embryos. The results were summarized as follows : 1. The rates of nuclear maturation, penetrated oocytes, polyspermic oocytes and mean numbers of the penetrated sperm were not different in the NCSU-23 maturation media with 0, 100, 500 and 1,000 units/ml SOD. However. the pronucleus formation rates were significantly lower in oocytes matured with addition groups than those of no addition groups of SOD (P>0.05). 2. The rates of blastocyst formation and total cell numbers of blastocyst at day 7 after in vitro fertilization were significantly lower in addition groups than those of the no addition groups of SOD (P>0.05). 3. The rates of blastocyst formation at day 7 after in vitro fertilization were higher in the NCSU-23 culture medium with 100 units/ml SOD than in those cultured with 0, 500 and 1,000 units/ml SOD under the 5% and 20% $O_2$concentrations. However, no differences was found in the total cell numbers of blastocyst among the treatments. In conclusion, these results suggested that the addition of SOD was not adequate for porcine oocyte maturation and further development, also the rates of blastocyst formation and total cell numbers of blastocyst at day 7 of porcine IVM/IVF embryos were not different in the NCSU-23 culture medium under the 5% and 20% $O_2$concentrations.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.114-118
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• 1991

This study was conducted to find out the suitable in vitro media for fertilization and culture on the pig oocytes matured in vivo and in vitro. The results obtained were as follows; A comparison of fertilization media on the oocytes matured in vivo was made between M199 with 10% FCS versus TL Hepes with 1% BSA Fertilization rate was significantly higher in the TL Hepes medium. But polyspermic incidence did not favor in the TL Hepes medium. Embryos were cultured in TL Hepes wash and culture medium for 48h after insemination. A total of 53 embryos were cultured and 39(73.6%) cleaved. Of these 39 embryos, 31(79.5%) cleaved equally to the 2-8 cell stage. Immature oocytes cultured in Waymouth's maturation medium were much more able to induce sperm swelling than immature oocytes cultured in TL Hepes maturation medium, however, most ova were polyspermic and did not develope to the 4 cell stage during 48h culture in TL Hepes wash and culture medium.

• Parasites, Hosts and Diseases
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• v.36 no.4
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• pp.217-225
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• 1998

A scanning electron microscopic study was performed to observe surface ultrastructures of excysted metacercariae and adults of Metagonimus miyatai. Metacercariae were collected from the scale of the pale chub (Zacco platypus). and adult flukes were harvested 1-4 weeks after infection to rats. In excysted metacercariae, the oral sucker was devoid of tegumental spines and had type I and type II sensory papillae. Anteriorly to the ventral sucker, spines were dense and digitated into 5-7 points, whereas near the posterior end of the body spines were sparse and digitated into 2-3 points. In one-week adults, 7 type II sensory papillae were arranged around the lip of the oral sucker. and at inner side of the lip one pair of small and two pairs of large type I sensory papillae were seen on each side. The distribution of tegumental spines was similar to that of metacercariae, but they were more differentiated with 9-11 pointed tips. In two- to four- week old adults, the surface ultrastructure was nearly the same as in one-week old adults, however, sperms were frequently seen entering into the Laurer＇s canal. Conclusively, the surface ultrastructure of M. miyatai was generally similar to that of M. yokogawai, however, differentiation of tegumental spines and distribution of sensory papillae around the oral sucker were different between the two species. which may be of taxonomic significance.

• Journal of Embryo Transfer
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• v.18 no.2
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• pp.143-149
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• 2003

This study was carried out to cryopreserve and to investigate characteristics of semen in Hanwoo. Semen was obtained from bulls selected by Daekwanryeong Branch station. Semen was collected each morning of the experiment, placed in water jacketed tubes at 37$^{\circ}C$, and trans-ported to the research laboratory within 10 minutes. Semen was extended with Egg yolk-glycerol extender to contain 50${\times}$10$^{6}$ sperm/ml. Semen was cooled over a 6h period in water jacketed tubes from about 25 to 5$^{\circ}C$, Egg yolk-glycerol extender was added in one step at 5$^{\circ}C$. Semen was aspirated into 0.5ml straws, which were sealed with powder. Egg yolk-glycerol extender, which is used in Hanwoo sperm frozen and stored, semen from 13 Hanwoo bulls collected, the postthawed percentages of motile sperm were 65.7%. In semen characteristics of Hanwoo bulls, number of bulls volume are 5.7 ml and total cell count are 975${\times}$10$^{6}$ m1 ejaculate.

• Research in Plant Disease
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• v.14 no.3
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• pp.214-218
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• 2008

Coleosporium neocacaliae, a needle rust fungus, was described and illustrated for the first time on the needles of Pinus koraiensis (Korean pine) in Korea. Detailed descriptions of the species were verified based on symptoms and signs, and light and scanning electron microscopic observations on aecia, aeciospores and peridial cells. The present needle rust fungus was apparently different from C. eupatorii, a solely recorded Coleosporium species on P. Koraiensis in Korea until this time, in having comparatively large sized aeciospores as $20-39{\times}14-27\;{\mu}m$ than those of latter species (size of aeciospores $15-27{\times}10-20\;{\mu}m$). Verrucose surface structure of aeciospores in light microscopy was revealed to be annulated with three to four rings and root-like base in scanning electron microscopy. Aecial stage of C. neocacaliae were formed on the middle days of April to the early days of June and collected around the central parts of Korean peninsula, including high mountains of about 1,000 m above sea level.

• Journal of the Korean Geophysical Society
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• v.2 no.3
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• pp.179-190
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• 1999

The overall structural framework was studied using the regional 2D seismic data, followed by the sequence stratigraphic study on the 3D seismic and well- log data in the margin of the South Con Son basin of the South China Sea. This research contributes to delineate depositional stratigraphy, depositional environment and geologic history in the 3D seismic area of highly complicated faulting. Eight Miocene sequences were indicated on the 3D seismic and well-log data, in which the structural maps of each sequence boundary and the isochron maps for the corresponding sequence were made. The seismic facies were analyzed for each sequence volume and sequence boundary surface. The 3D seismic area is characterized by coal beds deposited in the transgression environment (transgression systems tract) and channel distributions just above the sequence boundaries. During the Early Miocene, the coals and thick shales deposited in the mangrove swamp representing the lower coastal plain environment. During the Mid to Late Miocene, thick clastic sediments deposited in the coastal to shallow shelf by regional subsidence and marine transgression. The isochron maps and structural patterns indicate that the sediments were transported from west to east or from northwest to southeast.

• Korean Journal of Animal Reproduction
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• v.15 no.1
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• pp.41-47
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• 1991

The ability of fertilization in vitro and subsequent development of superovulated oocytes was assessed in a controlled environment using an in vitro fertilization technique. The in vitro fertilization percentage of oocytes with cumulus mass declined significantly(P<0.05) with increased doses from 4~10 to 16~40IU of PMSG for superovulation. However, the porportion of polyspermic penetration varied from 2.3 to 9.7% and there was no significant difference between treatments in incidence of polyspermy. When morphologically normal ova with cumulus mass were cultured for 66~72h in a plastic mini-straw to undergo fertilization in vitro, the mean percentage of embryos developed to 2-16 and 4-16cell stage was 61.8 and 17.6%; it was slightly(P<0.05) superior to the corresponding results from petri dish. A total of 52 two-cell embryos fertilized in a mini-straw were transferred to seven pseudopregnant rat. Among these recipients, two normal young were born from one recipient which received a total of six embryos. These results suggest that superovulated oocytes are proportionately less competent than normally ovulated oocytes to undergo fertilization in a controlled environment using an in vitro fertilization technique. Also, a plastic mini-straw designed was slightly superior to petri dish as a culture vessel for fertilization and embryo development in vitro.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.2
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• pp.59-67
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• 2022

In this study, the monthly airborne chlorides flying into the offshore bridges were investigated depending on the sea level. The target structures were 9 bridges located on the western and southern coast of South Korea. The airborne chlorides were measured at different sea levels on each bridge every month during 1 year. The results showed that the strongest seasonal wind from the northwest in winter expecially have led increase of the airborne chlorides, and its effect was more significant in the western coast than the southern coast. It was also found that the airborne chlorides declined with the increase of sea level. Three types of curves were suggested for analyzing the decrease trend with the sea level, based on the airborne chlorides at the lowest measurement height of main tower. The trend was varied depending on the sea area, and even in the same sea area, the local topographic condition affected the airborne chlorides. It means that the location and local topography should be considered simultaneously for durability management in the framework of the chloride source, and then the influence of the chloride source should be classified, e.g. safe and dangerous. From these results, it is expected that it could be used as baseline data for the evaluation of the deterioration environment in the Detailed guidelines for safety and maintenance of facilities [Performance evaluation]_Bridge.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.2
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• pp.1-11
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• 2015

This study sheds light on a pond design process which is a core facility of Hwaseol-dang in Muan, the Jeonnam. The plasticity of the pond was analyzed and interpreted for the design process using methods such as "literature search, interview, site visits, aerial pictures, aerial photographing, drawing figures of configuration plane via measurements, internet search, etc.", to trace the developing process of the design and the implications therein. The study results being centered on the developing process of the pond design are summarized herein below. The position of the Hwaseol-dang, being formed on a low hill having low competence as a place for a pavilion, draws more attention regarding its implications from the aspect of inner design. The pond Hwaseol-dang is in a rectangular shape of 1 : 1.2 ratio, in which the depth is a bit higher on the pond edge of the Hwaseol-dang thus being slanted, and Crape Myrtle, which is not known whether introduced during the formation of the pond, is cultivated on the island in the center widespread toward the southeast region. The planar design of the pond is interpreted as "rectangular pond" but it has a smooth half-moon shape where a part is excluded to remove edge. In particular, the three islands in rectangular pond, due to the narrow area, put one island and two half-moon-shaped islands in juxtaposition, and thus, although only being one island, resultantly exhibits the existence effect of proliferated three islands. This is allegedly due to the intentional formation aiming at the effect of hybrid while minimizing the overlap due to merging and adding from the aspect of constituting a design. Furthermore, the pond Hwaseol-dang is extended northwest along with Hwaseol-dang, and also the island in the center is thought to additionally have one or two, but the widespread phenomenon of the island in the center appears to consider the effect of "sit view on the floor of the pavilion of Hwaseol-dang". Considering that even a few examples of ponds having the three islands among the private house gardens in the nation are all curved ponds, the characteristics of the rectangular Hwaseol-dang pond establishing the garden effect of the three islands by modifying the one island in rectangular pond is highly notable. Considering that the three islands of "Yeongju, Bangjang, and Bongrae" is the original shape of the pond garden gestating Taoist ideology, as a symbolic design of a pond, it is regarded as the characteristics of the pond shape in Jeonnam area, and the so-called three treasures "Hwaseol-dang, Camellia, and oddly shaped stones, etc." are concentrated as the symbolism of Hwaseol-dang pond.