• Journal of Sericultural and Entomological Science
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• v.26 no.1
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• pp.25-29
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• 1984

Since 1966, practical use of active heavy analogs of the hormones has been also worked out as an insecticide and brought the features of it to the light as cocoon producer. On the other hand, it is expected to afford the increase of silk productivity resulted from control of the fifth larval period by delaying normal development. With these regards, some of analogs have been tried to apply practically to the silkworm for an increase of cocoon productivity. One of the synthesized juvenile hormone available is "Manina". And it is presently used for the increase of silk productivity in Korea. For the practical use, it is very essential the varietal differences in the increase of silk productivity by topical application was tested and the obtained results are summarized as follows. 1. It was evident that the fifty larval period was extended by topical application after 48 hrs. of the last ecdysis, ranging from 8 hrs. to one day, as compared to the control. 2. In pupal rates, there is no significance between control and treatments. It proved that there was no toxicity to silkworm by topical application in general, except jam 120. With regards to an increase of cocoon yield in Japanese, it was resulted from 17∼24% of cocoon yield from 10,000 larvae, as compared to that of control. In case of Chinese, the incrasing rates were varied from 15∼26% of cocoon yield, 17.8kg of it with 26% increase for Jam 122 and 16.7kg of it with 25% increase for Jam 118. In case of all hybrids, an increase of the cocoon yield took places from 20% to 31% and the weight of cocoon layer for the Japanese increased by 6 to 14%, those for the Chinese by 4 to 7% and those for the hybrids ranged from 21 to 29% increase. 3. It was recognized that the hybrid vigor rate took places with the hybrids between high responsing parents to juvenile hormones.

• Korean Journal of Environment and Ecology
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• v.23 no.6
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• pp.528-534
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• 2009

Styan's Grasshopper Warblers (Locustella pleskei) are vulnerable species distributed in East-Asia only. Its known breeding sites in Korea are remote islets including Hongdo Islet, Chilbal Islet, Mara Islet, and Chuja Islets, and, therefore, the breeding biology of this species is still poorly known. This study was conducted on Mara Islet (N $33^{\circ}$ 06', E $126^{\circ}$ 16') from May to September 2008 to investigate the breeding status and breeding site characteristics of the grasshopper warblers. A total of 11 breeding pairs and their nests were found on trees and shrubs at artificially planted forests and hedges of Pinus thunbergii. The grasshopper warblers preferentially utilized the shrub trees for nesting places, and major nesting trees were Camellia japonica, Pittosporum tobira and Pinus thunbergii as nesting trees. Average heights of nesting trees and nests were $2.77{\pm}1.10m$ and $1.75{\pm}0.56m$, respectively. The grasshopper warblers selected lower shrubs and trees for nesting than randomly selected ones around them, probably to avoid strong and prevailed winds in flat and un vegetated environments on Mara Islet. The shape of nests was a round bowl-type, and measurements of nests were $11.9{\pm}0.5cm$ in exterior nest diameter, $11.1{\pm}1.1cm$ in height of exterior nest, $5.8{\pm}0.4cm$ in interior nest depth, and 6.0cm in interior nest diameter. It incubated eggs until the early August on Mara islet, and incubation periods of Mara Islet was possibly later than that of other areas. Furthermore, the clutch size in the study area was three, and they laid smaller number of eggs than normal clutch size (4~5 eggs) reported in other areas. Although we could not observe any nest predator on this species in the study area, selective cutting and pruning of trees will diminish dense shrub layer of forests. Therefore, it may affect the breeding of this threatened species which prefers dense shrubs of artificially planted forest of Pinus thunbergii. This study suggests that detailed and consistent further research on breeding biology and habitats of the grasshopper warblers are needed to conserve and manage of Pinus thunbergii forests on Mara Islet as an important breeding site of Styan's Grasshopper Warblers.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.4
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• pp.83-97
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• 2011

In this study, space allocation with an assessment system for improving the function of the ecological use and function of each space was undertaken to suggest appropriate goals and directions. Ogeum Park, used as the study site, is a stronghold green zone located in the fan-shaped area of the Songpa-gu green zone on a 22ha area site. The assessment system for this study consisted of a total of 3 steps: Step 1 includes the division of the spatial block, Step 2 assesses the proper functioning of each spatial block, while Step 3 includes space allocation and presents improvements for function by space. This study performed a basin analysis with the consideration that Ogeum Park is a forest area and divided the site into a total of 8 areas according to how the sections of land are used. The function of wildlife habitat included an analysis of plant ecology(vegetation type, vegetation layer, potential vegetation), animal ecology(wild birds), and waterways. The function of leisure and use included an analysis of gradients, noise, paths, status of use, and status of facilities. The evaluation of the function of habitat sorted items into native vegetation, vegetation diversification, vegetation potential, animal diversification and potential of animal habitats. The results of grading the evaluation scores by space in the function of habitat showed that the Areas IV and VII, which were 90% of the maximum point, were Grade A, Areas II and V were Grade B at 70% and Area I and VI were Grade C at 50%. Areas III and VIII, which were not found to be beyond the standard of 50%, were excluded. The evaluation of the functions of leisure and use classified items into use potential, use preference, use concentration, use diversification and use convenience. The results of the graded evaluation scores by space in use function, showed areas V and VI as Grade A, or 90% of the maximum score. Grade B, 70% of the maximum score, was given to Areas I and VII. Grade C, 50% of the maximum score, included Areas II, IV and VIII. Area III, graded lower the standard of 50%, was excluded. The study evaluated areas according to a common standard, classified spaces by proper functions into ecological spaces, environmentally-friendly use spaces and use spaces according to the standard of spatial distribution on the basis of the above results through a synthesis of grades of habitat function, leisure function and use. This offers ideas for the improvement of wildlife habitat and environment-friendly use functions by space.

• Korean Journal of Poultry Science
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• v.47 no.2
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• pp.95-105
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• 2020

This study presents the production characteristics and physiological characteristics of five Korean native chicken (KNC) breeds consisting of Hwanggalsaek Jaeraejong (HJ), Korean Rhode Island Red (KR), Korean White Leghorn (KL), Korean Brown Cornish (KC), and Korean Ogye (KO). We investigated their production performances, vitalities, and stress responses. We measured the survival rate, body weight, age at first egg-laying, hen-day egg production, egg weight, amount of telomeric DNA, heterophil-lymphocyte ratio (H/L ratio), and heat shock protein (HSP)-70, HSP-90α and HSP-90β gene expression levels for 493 KNCs. The survival rate was highest in KR, and lowest in KO. Body weights were steadily high in the order of KC, KR, HJ, KO and KL. Average hen-day egg production was highest in KL, and lowest in KC. While the amount of telomeric DNA was highest in KR, and lowest in KC. Furthermore, both the H/L ratio and the HSP-90β gene expression level were highest in KC, and lowest in KR. These results indicated that the KR breed was highly resistant to stress, whereas KC was more susceptible to stress. Taken together, it is considered that with improvements the KC breed would be more suited to be used as a Korean broiler breed while KL would be more appropriately used as a Korean layer breed. In addition, it is considered that the KR breed is appropriate to be used as a maternal chicken breeder based on good production capacity and excellent robustness, while the HJ breed is desirable to be improved as a high-quality Korean meat breed based on its excellent meat quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.77-85
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• 2002

In the southern sea of Korea and the areas of Tsushima warm currents the relationship between the distributions of eggs and larvae of anchovy (Engraulis japonica) and oceanic conditions was examined on July and August 1997, The south Korean coastal waters, the water temperature of below $20\~23^{\circ}$ and the salinity of above 33.0 (PSU), the mixed waters between the south Korean coastal waters and the Tsushima warm currents, $21\~25^{\circ}$ and $32.0\~32.5$ and the Tsushima warm currents, above $26^{\circ}$ and below 31.5 were distributed at the surface layer. The Tsushima warm currents were distributed at the northeast of Jeju Is. and off the southern sea of Korea. As an appearance of warm streamer, the mixed waters were intruded into the coastal areas of Komun Is.$\~$Sori Is. and Sori Is.$\~$Yokji Is.. Approximate paths of surface water by the drift card experiments were similar with the intrusions of the warm water identified from the water temperature and salinity distributions. The distributions of chlorophyll concentration were consistent with the distributions of water temperature and salinity, Anchovy eggs and larvae were mostly distributed at Komun Is., Yokji Is, and the southwest of Koie Is. where chlorophyll concentrations were high and cyclonic circulations by the warm water intrusions (warm streamers) were formed.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.3
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• pp.178-184
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• 2001

A study was carried out to investigate the effect of rice bran and charcoal meal application on growth in rice and bacterial population in paddy soil. Four different treatments were applied ; at whole layer placement of rice bran 1.8Mg/ha(1.8WR), surface of rice bran 1.8Mg/ha(1.8SR), charcoal meal 3.0Mg/ha(3.00M), and combined rice bran 1.8Mg/ha and charcoal meal 3.0Mg/ha (1.8R+3.0C) through field experiment. $NH_4-N$ and $NO_3-N$ in soil were high in the application of 1.8SR and 1.8R+3.0C until heading stage after rice bran application. Amount of nitrogen absorbed by rice plant were the highest in application of 1.8R+3.0C, and the lowest in application of 3.0CM. Rice yield was no differences among treatments. A number of total aerobic bacteria were the highest in application of 1.8R+3.0C at panicle formation stage of rice. Cellulose decomposers were high in application of 1.8SR at tillering stage and in application of 1.8R+3.0C at harvesting stage. The microorganisms of ammonia-oxidizing and denitrifying bacteria showed higher number in the application of 1.8R+3.0C and 1.8SR at tillering stage than heading stage. Azotobacter had tendency to decreased with the passage of time, but increased when rice bran was added. Athiorhodacea were numerous in the application of 1.8WR, but a few in the application of 3.0CM through growing period of rice plant.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.255-262
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• 1994

Field microplot(D 20cm, L 85cm) experiment filled with Bonryang sandy loam soil(Typic Udifluvents) was conducted to obtain quantitative information on the movement of applied nutrients under different soil moisture regimes and ladino clover cultivation. The slaked lime was detected as an exchangeable Ca in the layer applied. The released Ca into the soil water proceeded rapid downward movement. Ca content in the soil was lowest at 20~30cm and tended to increase with soil depth. Downward movement of Mg in the slaked lime was similar to the movement of Ca to a greater extent. Plant uptake of Mg and leaching loss out of the microplot increased with lowering soil moisture tension. Downward movement of K was rapid in comparision with Ca and Mg. Lowering soil moisture tension enhanced both plant uptake and leaching loss of applied K. Irrigation at 0.2bar soil miosture condition increased plant uptake of Ca, Mg and K by 55, 71 and 76 % to compare to the plant uptake of Ca:0.49g, Mg:0.21g and K:1.90g/microplot at the nonirrigated condition respectively. Distribution of each of these elements seemed to be greatly affected by the downward movement of Ca with soil moisture, plant uptake of Mg(69%), and plant uptake and downward movement of K.

• Food Science and Preservation
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• v.22 no.4
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• pp.512-519
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• 2015

In this study, the effects of gamma-radiation treatment on cell wall composition and physiological characteristics of astringent persimmon fruit were investigated. The soluble tannin contents of gamma-radiated samples were reduced by the radiation treatment. The hardness of the radiated fruit was decreased when compared to non-radiated fruit. Alcohol-insoluble component of the cell wall in the radiated fruit was decreased from 39.3 mg/g to 37.2 mg/g. The water-soluble content of the radiated fruit was increased from 11.4 mg/g to 13.9 mg/g. The cell wall content of the non-radiated fruit was 26.6 mg/g whereas the cell wall content of radiated fruit was decreased to 23.1 mg/g. Due to the maturation of astringent persimmon fruit by gamma-radiation, water-soluble compounds were increased whereas decreasing in cell wall compounds. The contents of lignin, pectin, and cell wall were decreased from 0.82 mg/g and 3.56 mg/g to 0.77 mg/g and 3.14 mg/g, respectively. Acid-soluble hemicellulose content was decreased by gamma-radiation, while alkali-soluble hemicellulose and cellulose contents were increased. Activities of sotening enzyme as polygalacturonase, pectinesterase and $\beta$-galactosidase existed in persimmon fruit were increased by gamma-radiation. In the sensory evaluation, gamma-radition treated persimmon showed very low astringent taste when compared to the non-radiated fruit. In hardness test, the non-radiated persimmon maintained the hardness while gamma-treated persimmon showed softened outer layer due to the condensation of tannin during radiation treatment. Therefore, gamma-radiation treatment will be used for the removal of its astringency of persimmon fruit and for enhancement of its maturation.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.139-151
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• 2018

The National Base Map construction consists of the regular correction work of dividing the whole country into two regions and carrying out the modification Plotting by aerial photographs every two years as well as the real time updating work of correcting the major change feature within two weeks by the field survey and the As-Built Drawing. In the case of the Building Layout Drawing of Korea Real estate Administration intelligence System(KRAS) used for real time updating work of the National base map, the coordinate transformation error is included in the positional error when applied to the National Base Map based on the World Geodetic Reference System as the coordinate system based on the Regional Geodetic Reference System. In addition, National Base Map is registered based on the outline(eaves line) of the building in the Digital Topographic Map, and the Cadastral and Architecture are registered based on the building center line. Therefore, the Building Object management standard is inconsistent. In order to investigate the improvement method, the network RTK survey was conducted directly on a location of the Building Layout Drawing of Korea Real estate Administration intelligence System(KRAS) and the problems were analyzed by comparing with the plane plotting position reference in National Base Map. In the case of the general structure with the difference on the Building center line and the eaves line, beside the location information was different also the difference in the ratio of the building object was different between Building center line and the eave. In conclusion, it is necessary to provide the Base data of the double layer of the Building center line and the outline of the building(eaves line) in order to utilize the Building Layout Drawing of Korea Real estate Administration intelligence System(KRAS). In addition, it is necessary to study an organic map update process that can acquire the up-to-dateness and the accuracy at the same time.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.11-18
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• 2004

The eruption of permanent teeth represents the movement in the alveolar bone before appearance in oral cavity, to the occlusal plane after appearance in oral cavity, and additive movement after reaching th the occlusal plane. Tooth eruption is mostly controlled by genetic signals. The eruption stage is divided to preeruptive alveolar stage, alveolar bone stage, mucosal stage according to the process of growth and development. If the disturbance is occured in any stage of eruption, tooth does not erupt. The cause of eruption disturbance are ectopic position of the tooth germ, obstruction of the eruption path and defects in the follicle or PDL. In the treatment of eruption disturbance, surgical procedures are commonly used. There are three kind of surgical procedure ; surgical exposure, surgical repositioning, surgical exposure and traction Surgical exposure is basic procedure. This involves removal of mucosa, bone, lesion that are surrounding the teeth, dental sac when necessary to maintain a patent channel between the crown and the normal eruptive path into the oral cavity. To ensure this patency, many techniques including cementation of a celluloid crown, packing with gutta-percha or zinc oxide-eugenol, or a surgical pack, are used. When surgical exposure is conducted, operators should not expose any part of cervical root cement and not injure periodontium or root of adjunct tooth. After surgical exposure, tooth should be surrounded by keratinized gingiva. There is direct relationship between the extent of development of pathophysiologic aberrations and the intensity of the manipulative injury inflicted on the tooth by surgical treatment, so operator should consider this thing. In these cases, surgical exposure is conducted on Maxillary 1st milars that have a eruption disturbance and improve the eruption disturbance effectively.