• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.2
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• pp.117-134
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• 1998

The study on the Assembling Mechanism of the Hairtail, Trichiurus lenpturus, at the Fishing Grounds of the Cheju Strait had been investigated by analyzing the relationship of the oceanographic conditions and the fishing ground of the Hairtail in the Cheju Strait. 1. The fishing grounds of the hairtail at the Cheju Strait are formed at the bottom of a high temperature of the tidal front at the coast. area of northern Cheju Island, the tip of the linguiform is high in salinity at the eastern and western entrances of Cheju Island, low salinity eddy on the surface and its surrounding front, various water masses in the Strait and coastal waters of the South Sea in Korea. 2. The fishing grounds of the Hairtail at the Cheju Strait begins with the sea surface temperature higher than $15^{\circ}C$ and the incoming of low salinity water now from the East China Sea. 3. Estimation of optimum temperature and salinity per season based upon analysis for relationship between temperature of water and salinity of the bottom layer and the catch is : 15.2~$16.4^{\circ}C$, 34.20~34.40${\textperthousand}$ in spring(June); 14.4~ $17.0^{\circ}C$, 33.70~34.30${\textperthousand}$ in summer(July~September); and 15.7~ $18.6^{\circ}C$, 33.70~34.50$\textperthousand$ in autumn(October~December). Hairtail are mostly caught at the Yellow Sea Warm Current and Tsushima Current with temperature over $14.5^{\circ}C$ and salinity over 33.70${\textperthousand}$ at the bottom layers of the Cheju Strait. 4. Considering the relationship between the amount of hairtail catch and the water temperature of bottom layer, when the bottom water being above $14.0^{\circ}C$ flowed into Cheju Strait through the western entrance of the strait in summer, the ca-h appears to have been abundant. In contrast, the catch has been poor when the temperature of such water was recorded to be below $13^{\circ}C$ Therefore, distribution patterns of water at the bottom layer can be used as a forecast index whether the catch of a certain year will be good or poor.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11a
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• pp.29-30
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• 2002

The goal of this research was to develop the effectiveness of in vitro culture method for A. formosanus and study the environment in vitro conditions affecting on growth. The first series of experiments were examined to investigate the response of three different basal media, MS (Murashige and Skoog, 1962), Knudson (KC; Knudson, 1946) and modified hyponex on growth and multiplication during in vitro culture. Multiple shoot proliferation was induced in shoot tip explants on Hyponex (H3) media supplemented with BA (1 mg1$\^$-1/) or TDZ (1-2 mg1$\^$-1/). Addition of activated charcoal (1%) to the TDZ containing medium promoted rapid shoot tip proliferation (11.1 shoots per explant) but the same medium had an opposite effect resulting in poor proliferation in the nodal explants. However, the regenerated shoots had slow growth rate and failed to elongate. This problem was overcome by transferring the shoot clumps to a hormone free H3 media supplemented with 2% sucrose and 0.5% activated charcoal. Using bioreactor culture for scaling up was also shown the best way for multiple shoot induction and growth of this plant. The second series of experiments was studied to investigate the effect of physical environment factors on growth of in vitro plantlets. The Anoectochilus formosanus plantlets were cultured under different air exchange rate (0.1, 0.9, 1.2h$\^$-1/), without sucrose or supplement 20g.1$\^$-1/ (photoautotrophic or photomixotrophic, respectively), and different photosynthesis photon flux (40, 80, 120 ,${\mu}$mol.m$^2$.s$\^$-1/- PPF). Under non-enrichment CO$_2$ treatment, slow growth was observed in photoautotrophical condition as compared with photomixotrophical condition on shoot height, fresh weigh and dry weight parameters; High air exchange (1.2.h-l) was found to be inadequate for plant growth in photomixotrophical condition. On the contrary, under CO$_2$, enrichment treatment, the plant growth parameters were sharply (visibly) improved on photoautotrophic treatments, especially on the treatment with air exchange rate of 0.9.h-1. The growth of plant in photoautotrophic condition was not inferior compared with photomixotrophic, and the best growth of plantlet was observed in treatment with low air exchange rate (0.9.h-1). Raising the PPF level from 80 to 120${\mu}$mol.m$\^$-2/.s$\^$-1/ decreased the plant height, particularly at 120${\mu}$mol.m$\^$-2/.s$\^$-1/ in photoautotrophic condition, fresh weight and dry weight declined noticeably. At the PPF of 120${\mu}$mol.m$\^$-2/,s$\^$-1/, chlorophyll contents lowed compared to those grown under low PPF but time courses of net photosynthesis rate was decreased noticeably. Light quality mainly affected morphological variables, changes of light quality also positively affected biomass production via changes in leaf area, stem elongation, chlorophyll content. Plant biomass was reduced when A. formosanus were grown under red LEDs in the absence of blue wavelengths compare to plants grown under supplemental blue light or under fluorescent light. Stem elongation was observed under red and blue light in the present experiment. Smaller leaf area has found under blue light than with other lighting treatments. Chlorophyll degradation was more pronounced in red and blue light compared with white light or red plus blue light which consequent affected the photosynthetic capacity of the plant. The third series of experiment were studied to investigate the effect of physical environment factors on growth of ex vitro plants including photosynthesis photon flux (PPF), light quality, growing substrates, electrical conductivity (EC) and humidity conditions. In the present experiments, response of plant on PPF and light quality was similar in vitro plants under photosynthesis photon flux 40${\mu}$mol.m,$\^$-2/.s$\^$-1/ and white light or blue plus red lights were the best growth. Substrates testing results were indicated cocopeat or peat moss were good substrates for A. formosanus growth under the greenhouse conditions. In case of A. formosanus plants, EC is generally maintained in the range 0.7 to 1.5 dS.m-1 was shown best results in growth of this plant. Keeping high humidity over 70% under low radiation enhanced growth rate and mass production.

• Korean Journal of Agricultural Science
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• v.36 no.2
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• pp.123-127
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• 2009

This study was carried out to gain the informations about seedling transplanting cultivation of Daehakchal Gold 1 which was developed at the Corn Breed. and Genetics Lab., Coll. of Life and Sci., Chungnam Nat'l Univ. in 2009. This hybrid and Check were sowed over four times at intervals of 10 days from 15th April(1st) to 30th May(last) and transplanted at CNU Corn Breed. Farm the 20th seedling cultivated after sowing, respectively. Results obtained from this experiment were as follows; stem height of this hybrid were variable regardless of sowing and transplanting times, while ear height was gradually increased according to delay of sowing times. Ear size and sharp of fresh corn as one of important traits was good at 2nd harvest times, while tip filling of ear harvested at 1st time was not good and also it's size decreased according to delay of transplanting stage. Stability of this hybrid expressed as ratio of stem height to ear height was very good as 50% below. Accordingly, the proper sowing and transplanting times of Daehackchal Gold 1 considered the late in April to early in May as harvesting proper period.

• Korean Journal of Veterinary Research
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• v.21 no.2
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• pp.151-159
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• 1981

An investigation on various causes of milking disturbances resulting from injuries and abnormalities of mammary system were made in 2,179 Holstein cows. To perform this investigation, 69 dairy farms of the suburban area of Seoul city, Gyeonggi-do and Chungnam provinces were andomly selected and subjected. Diagnosis was made by means of inspection and palpation of teat, insertion of teat canula, checking milk machines, anamneses and farm records. This investigation was, actively done from March 1977 to February 1979, The results obtained were summerized as follows; 1. It was found that 446 cows, accounting for 20.48% of 2,179 cows inspected, had supernumerary teats. Among them 53.59% had one, 43.72% had two, 2.47% had three, and 0.22% had four supernumerary teats, respectively. 2. Dry off quarters were found in 158 quarters which turned out to be 1.8% of 8,716 quarters inspected. Among dry off quarters, 62.02% seemed to be caused by mastitis, 30.37% by acquired teat obstructions, and 7.59% by congenital blind teats and glands respectively. 3. Teat sphincter stenosis was found in 154 teats of 50 cows, which represents 1.76% of 8,716 teats and 2.29% of 2,179 cows inspected, respectively. Among 154 teats with teat sphincter stenosis, 138 teats (85.7%) of 33 cows were found to be congenital and revealed highest incidence. 4. Loose sphincter was found in 78 teats of 36 cows, which figure 0.89% of 8,7l6 teats and 1.69% of 2,179 cows inspected, respectively. Among 78 teats with loose sphincter, 52 teats (66.66%) of 13 cows were found to be congenital and revealed highest incidence. 5. Injured teat tip caused by over milking of milk machine, was found in 229 teats of 156 cows, which figure 2.63% of 8,716 teats and 7.15% of 2,179 cows observed, respectively. 6. Other miscellaneous injuries and congenital abnormalities of teats and udders were diagnosed as follows: The teat laceration was found in 34 teats (0.39% of 8,716 teats), fissure of teat skin in 24 teats (0.28% of 8,716 teats), stricture of teat cistern in 21 teats (0.24% of 8,716 teats), teat fistula in 12 teats (0.14% of 8,716 teats), papillomas on testes in 8 teats (0.09% of 8,716 teats). Knothole orifice in 7 teats (0.08% of 8,716 teats), subcutaneous abscess of udder in 5 quarters (0.05% of 8,716 teats), membraneous obstruction of teat cistern in 4 teats (0.05% of 8,716 teats), and congenital short teat in 8 teats (0.09% of 8,716 teats), respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2359-2368
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• 2013

Cone penetration tests (CPTs) have been increasingly used for site characterizations. However, the site investigations using CPTs are often limited due to soil conditions depending on the cone size and capacity of the CPT system. The small sectional area of a miniature cone improves the applicability of the CPT system due to the increased capacity of the CPT system. A continuous intrusion system using a coiled rod allows fast and cost effective site investigation. In this study, the performance of the continuous intrusion miniature cone penetration test (CIMCPT) system has been evaluated by comparison tests with the standard CPT system at several construction sites in Korea. The results show that the CIMCPT system has a same performance with the CPT system and has advantages on the mobility and applicability. According to field verification tests for scale effect evaluation, the cone tip resistance evaluated by CIMCPT overestimates by 10% comparing to standard CPTs. A crawler mounted with the CIMCPT system has been implemented to improve accessibility to soft ground, and has shown improvement over the truck type CIMCPT system. Therefore, the improved CIMCPT system can be utilized as a cost effective and highly reliable soil investigation methodology to detect the depth of soft ground and to evaluate soil classification.

• Horticultural Science & Technology
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• v.16 no.3
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• pp.370-373
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• 1998

Fumigation by combination of methyl bromide/phosphide ($MB/PH_3$) was much more effective in disinfestating the rose insect pests (Aphis gossypii, Tetranychus urticae, and Frankliniella occidentalis) than that by individual MB or $PH_3$. Fumigation for 2 hours in the chamber using ;$MB/PH_3$ at the concentration of $10/3g{\cdot}m^{-3}$ brought about 91.3% and 100% mortality in aphids and thrips, respectively. Fumigation for 3 hrs using ;$MB/PH_3$ at the concentration of 5/3 or $7/3g{\cdot}m^{-3}$ showed over 96% mortalities in mites and thrips as well as no phytotoxicity symptoms, e.g. tip burn or bent neck, in cut roses, while mortalities of mites and thrips were not influenced by increasing $CO_2$ concerntration from 0.03% to 10% or decreasing $O_2$ concentration up to 15% in fumigation chamber.

• Journal of Korean Society of Forest Science
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• v.70 no.1
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• pp.72-76
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• 1985

Populus alba ${\times}$ P. glandulosa cuttings in nursery bed were inoculated with mycelium of ectomycorrhizal fungus, Pisolithus tinctorius (Pt) to evaluate effectiveness of the fungus in growth stimulation of poplar. Pt was cultured in 1l glass bottles with vermiculite-peatmoss mixture moistened with modified Melin-Norkrans' solution. The nursery bed was arranged for microplots of $1{\times}2m$ in size and fumigated with methyl bromide before inoculation and cutting placement. Fifty cuttings were placed in each microplot and two treatments (fumigation only and fumigation plus Pt inoculation) were replicated three times. At the end of the first growing season, inoculated plants grew 19% faster in height and produced 49% more dry weight (above-ground portion) than uninoculated plants. Survival rate of inoculated cuttings was also improved by 20% over that of uninoculated cuttings. Inoculated cuttings developed abundant fine root system with golden brown zigzag tips. In the middle of September a sporocarp of Pt was produced from an inoculated plot, suggesting successful establishment of mycorrhiza between poplar and Pt fungus.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.335-343
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• 2003

An experiment was conducted to investigate types of injury inflicted by the stone leek leafminer, Liriomyza chinensis Kato (Diptera: Agromyzidae) on welsh onion. A feeding scar made by an adult female was a hole round in shape, with diameter of 0.08 mm and 0.48 mm in lesion, resulting in a white spot, many of which often form vertical dotted lines on a leaf. Egg spots were oval with 0.1 ${\times}$0.14 mm in size, one or several of which often form a V-shape in group. Feeding by adults began immediately after emergence and was very active from 4th to 5th day. Oviposition was done from 2nd to 6th day after emergence. In both feeding and oviposition, they were more active in the day time. Larvae after emergence crawled up the leaf at first, and then moved up and down to feed on mesophyll. When in high density, they feed on leaf from leaf tip to bottom, and let the leaf die. Area of damage per one larva was calculated as 72.1 $\textrm{mm}^2$. The aged larvae escaped from the leaf in early morning, usually between 5 and 7 am. Most pupation sites were distributed near plants,5cm in soil depth and within 10 cm away from the plant. Pupae of L. chinensis overwintered 10cm below soil surface and emerged from early May to late June the next year Adults then moved to welsh onions near over wintering sites, nursery, transplanted, and levee.

• Progress in Medical Physics
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• v.12 no.1
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• pp.19-29
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• 2001

In dose modeling, the shape of actual source and sealed capsule are important parameter to determine the physical dose computation. The author investigated the effect of filter of source self-absorption and sealed capsule to designed the high dose rate Ir-192 source for Ralstron(Japan) unit. The size of source designed to 1.5 mm $\Phi$ x 1.5mm length of actual source sealed with stainless steel which is 3.0mm $\Phi$ x 12.0mm length connected to driving cable. The dose attenuation was derived 66.3 % from 2655 segmented source at reference point of 10mm lateral distance of source. The output dose rate factor in tissue for designed source showed 0.0013511 cGy/mCi-sec in reference point at 1cm lateral distance of source center. The dose distribution at inferior of source showed the 52% of that of source tip region, however, the filtering effect was small as 4% at 45degrees of source axis. The dose attenuation within 20 degrees of source axis at near source-cable connector showed large filtering effect as 40% over, but the small effect was revealed isotropic dose distribution at large angle.

• Imaging Science in Dentistry
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• v.39 no.3
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• pp.149-156
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• 2009

Purpose : The purpose of this study was to develop a stent-based image guided surgery system and to apply it to oral and maxillofacial surgeries for anatomically complex sites. Materials and Methods : We devised a patient-specific stent for patient-to-image registration and navigation. Three-dimensional positions of the reference probe and the tool probe were tracked by an optical camera system and the relative position of the handpiece drill tip to the reference probe was monitored continuously on the monitor of a PC. Using 8 landmarks for measuring accuracy, the spatial discrepancy between CT image coordinate and physical coordinate was calculated for testing the normality. Results : The accuracy over 8 anatomical landmarks showed an overall mean of $0.56{\pm}0.16\;mm$. The developed system was applied to a surgery for a vertical alveolar bone augmentation in right mandibular posterior area and possible interior alveolar nerve injury case of an impacted third molar. The developed system provided continuous monitoring of invisible anatomical structures during operation and 3D information for operation sites. The clinical challenge showed sufficient accuracy and availability of anatomically complex operation sites. Conclusion : The developed system showed sufficient accuracy and availability in oral and maxillofacial surgeries for anatomically complex sites.