• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.503-507
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• 2019

Asteroid specimens were collected using fishing nets from the East Sea, Korea. The specimens were identified as Solaster paxillatus Sladen, 1889, belonging to the family Solasteridae of the order Valvatida. This species can be distinguished from three other Korean Solaster species by having 10 arms; subambulacral spines comprising four or five near base of arm, six or seven in middle part, and five or six in distal part of arm; furrow spines comprising four or five near basal part and three or four in distal part of arm; and suboral spines comprising more than ten spinules. The morphological characteristics of this species were described with illustrations. Solaster paxillatus is first reported in marine fauna of Korea.

• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.1
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• pp.2925-2933
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• 1973

For the efficient utilization of farm machines on the inclined uqland, work performance in plowing, harrowing and terracing and critical workable gradients were tested on three farm machines which are 47 ps-farm tractor, 8 ps-power tiller and 5 ps-power tiller. The results of this study are summarized as follows; 1) The steeper the slope of the upland was the more inefficient the work performance of all machines was. 2) The critical workable gradients of the machines were proved as 14 for 47 ps-farm tractor, 12 for 8 ps-power tiller and 10 for 5ps-power tiller. 3) Plowing in the way of turning the furrow slices against the slope in order to build up terraces, the critical workable gradients were 8 for 47 ps-farm tractor and 8 ps-power tiller and 6 for 5 ps-power tiller. 4) Two-way plow is recommended for plowing with farm tractor on inclined upland, and high lug of tire would be good to prevent the slippage, and side valance-weight should be attached to power tiller for preventing its overturning.

• Animal Systematics, Evolution and Diversity
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• v.36 no.4
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• pp.420-423
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• 2020

As a result of continuous taxonomic studies on the Korean crabs, Carcinus aestuarii Nardo, 1847 belonging to the superfamily Portunoidea is newly reported from Korean waters. Carcinus aestuarii has characteristics as followings: cardiac, hepartic and brachial regions are divided by deep furrow; shape of three lobes in frontal area is flatter with hairy; inside of carpus is with one sharp tooth; the posterior-lateral margin of the carapace is concave, and so on. The examined specimen doesn't have hairy and bump on outer margin of the chelipeds which differed from the previous description of the specimens collected from Tokyo Bay, Japan. Here, the diagnosis and the picture of Korean specimen is provided. Korean portunoids currently consist of 20 species belonging to 10 genera.

• Applied Microscopy
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• v.50
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• pp.13.1-13.7
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• 2020

We examined the morphology of fertilized egg and ultrastructures of fertilized egg envelopes of Ancistrus cirrhosus belong to Loricariidae using light and electron microscopes. The fertilized eggs formed a mass on the spawning place and were yellowish, spherical, non-transparent, demersal, adhesive, and a narrow perivitelline space. But, the adhesiveness of fertilized eggs was disappeared after spawning excluding contact parts. The micropyle with funnel shape was surrounded by 15-19 furrow lines of egg envelope in a spoke-like pattern. The outer surface of egg envelope has smooth side and inner surface of egg envelope was rough with grooves. Also, the total thickness of the fertilized egg envelope was about 32.58 ± 0.85 ㎛ (n = 20), and the fertilized egg envelope consisted of three layers, an outer adhesive electron-dense layer, a middle layer with low electron density and an inner electron-dense layer with grooves in counter structure from other most teleost. Collectively, these morphological characteristics and adhesive property of fertilized egg, and ultrastructures of micropyle, outer surface, and section of fertilized egg envelope are showed species specificity.

• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.149-157
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• 1978

This study was carried out to obtain basic data for the type selection of furrow openers for the no-tillage soybean planter trailed by the two-wheel tractor from the standpoint of minimum draft and good performance of furrowing. For this study, two models of furrow opener, hoe and disc type, were tested on the artificial soil stuffed in the moving soil bin. The results obtained were as follows. In the case of disc furrow opener, the drafts were measured according to various diameters of discs under the condition of disc angle $8^{\circ}$ and $16^{\circ}$, working depth 3cm and 6cm, working speed 2.75cm/sec. Minimum draft appeared when the diameter of disc was about 28cm and the drafts increased as the diameter of discs became larger or smaller than this diameter. Specific draft showed almost same tendencies as above but showed the minimum when the diameter was about 30cm. For the purpose of controlling the seeding depth, the relationships between draft and working depths, 3cm and 6cm, were tested. The variations of draft concerning the various working depths showed linear changes and were affected in higher degree by depths than other factors. There were general tendencies at both working depths, 3cm and 6cm, that total draft showed the minimum with the disc diameter of about 28cm and specific draft showed it with the disc diameter of about 30cm regardless of disc angle and working speed. For the purpose of controlling the working width and speed, the relationships among drafts, disc angle and working speed were investigated and there were general tendencies that the draft increased as the angle and speed were increased and the draft was affected more by speed than by angle. To compare the hoe-type with disc-type opener, the specific drafts of hoe openers were compared with those of disc opener of $16^{\circ}$ angle and 30cm diameter. The specific draft of disc-type opener with the diameter of 30cm was $0.35{\sim}0.5kg/cm^2$, while $0.71{\sim}1.02kg/cm^2$ in the case of hoe type with the lift angle of $20^{\circ}$ which is 2 times as much as that of disc type in average value. And the furrows opened by disc openers were cleaner than those opened by hoe openers.

• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.201-205
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• 2000

Eleven runoff $plots(3{\times}15\;m)$ were built on a sloping field of a high plateau in Kangwon Province, Korea. The plots were treated with different tillage, residue covers and fertilizers, corn and potato were cultivated, and sediment discharge was measured from the plots for 3 years. Agricultural management practices were monitored around the plots to develop adequate best management practices. The least sediment occurred from the plots with no-till and 100% residue cover $(corn,\;0.1{\sim}2.2\;t/ha/year)$ and with contour tillage and vinyl sheet cover plots $(potato,\;0.1{\sim}0.2\;t/ha/year)$. The largest sediment was measured from the plots with up-and-down till and no cover ($11{\sim}33$ and $16{\sim}31\;t/ha/year$ from corn and potato plots, respectively). The type of organic and commercial fertilizers seemed not to affect sediment discharge. Sediment discharge from contour plots were largely dependent on the collapse of ridges due to the flush of water stored in furrows. The sediment discharge from contour corn and potato plots with no residue cover was $10{\sim}27$ and $16{\sim}24\;t/ha/year$, respectively. No-till with residue cover, vinyl cover for tuber crops, construction of furrow dam, frost heave research, furrow and ridge tillage with furrow dam after tuber crop harvest, limited stalk harvest of row crops, use of winter cover crops, and other common best management practices were recommended to minimize the sediment discharge from a high plateau sloping land culture.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.221-224
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• 2006

To analyze how the furrow directions made by the azimuth of $90^{\circ}-270^{\circ}(N\;90^{\circ})$, $120^{\circ}-300^{\circ}(N\;120^{\circ})\;and\;0^{\circ}-180^{\circ}(N\;180^{\circ})$ effect on the growth characteristics and yield of 2 and 3-year-old ginseng, both of $N\;90^{\circ}\;and\;N\;180^{\circ}$ compared with$N\;120^{\circ}$ recommended as the standard practices for ginseng cultivation. $N\;90^{\circ}$ showed lower quantum and air temperature during forenoon, while it showed higher quantum and air temperature from 15:00 to 19:00 than that of $N\;120^{\circ}$. $N\;180^{\circ}$ showed high quantum and air temperature due to the distinct increase of sunlight penetrated from 9:00 to 11:00, and which were similar to that of$N\;120^{\circ}$ during afternoon. Stem length and leaf area in $N\;90^{\circ}\;and\;N\;180^{\circ}$, respectively, were decreased more than that of$N\;120^{\circ}$, and those in $N\;180^{\circ}$ were decreased more distinctly than $N\;90^{\circ}$. Heat injury rate was decreased in $N\;90^{\circ}$, while it was increased distinctly in $N\;180^{\circ}$ that showed high quantum and air temperature, and which showed great variation according to the year. Yield of $N\;180^{\circ}$ was decreased more than that of$N\;120^{\circ}$ in 2004, the year when it was a relatively high air temperature during summer season, but which was increased more than that of$N\;120^{\circ}$ in 2005 showing a rotatively low air temperature.

• Journal of Biosystems Engineering
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• v.12 no.3
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• pp.30-41
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• 1987

The geometrical shape of a plow bottom may be the most important factor affecting the performance of a plow for a given soil and operating conditions. There are various designs of the Jaenggi (Korean plow) available commercially, which may be different from each other and from the plow (Western plow) in respect to the shape and performance. This study was intended to investigate the geometrical characteristics of Jaenggi. The coordinate digitizer equipped with 3 potentiometers was designed and manufactured for measurement of the shape of curved plane of moldboard and share. The digitizer was connected to a microcomputer having the data acquisition system. This device was used to analyze the plow bottoms of 5 differently-made Jaenggis and one cylindrical plow. The results of the study are summarized as follows: 1. It was possible to measure easily and quickly the curved plane of plow bottom and to plot the view on three major plans using the coordinate digitizer electrically connected to a microcomputer system. 2. The shape of five Jaenggi bottoms analyzed could be characterized by the cutting angle having the range of $33-42^{\circ}$, the maximum share-lift angle of $41-50^{\circ}$, and the setting angle of moldboard wing of $46-70^{\circ}$. The most critical difference of the shape factors between the Jaenggi and the plow was found in the maximum share-lift angle, the former was more than twice as much as the latter. 3. The analysis of the shape of Jaenggi bottoms showed that the share projections on 3 major plans had a varied triangle, which was quite different from that of plow bottom. Especially, it was analyzed that the shape of furrow slice for the Jaenggi had a skewed rectangle, leaving a considerable height of the ridge at the furrow bottom. 4. The dihedral angle was similar range of $30-85^{\circ}$ for the all bodies investigated, but the directional angle was somewhat different from each other. The difference in directional angle was $5^{\circ}$ for the plow, $20^{\circ}$ for the Jaenggi A and $30^{\circ}$ for the Jaenggi B. 5. Area of the spherical representation region was 0.0328 for the plow, 0.1194 for the Jaenggi A and 0.1716 for the Jaenggi B. This may indicate that the plow came close to a working surface and the Jaenggi A and the Jaenggi B departed from a working surface to a somewhat greater extent.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.271-276
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• 1983

In field studies, the insecticides carbofuran(Furadan 3G) and diazion(3G) at the rate of 1,8 kg a.i./ha as a single side-furrowing treatment from March 13 to April 10(7 to 10 days intervals) were evaluated in terms of the control effects to the onion maggots(Hylemyia antique Meigen) and some phytotonic effects to the garlic plants. The treatments with carbofuran were significantly more effective in onion maggot control than the treatment with diazinon and untreated, and the earlier treatments the better control effects were obtained. Phytotonic effects only with carbofuran on garlic plants were of served as increases ranged $16.5\~23.2\%$ in plant heights, $22.0\~32.0\%$ in stem diameters and $15.5\~22.8\%$ in bulb diameters compared to the untreated. The greatest yield of garlics was resulted in the plots of Match-13 treatments with carbofuran, ca. 10,700kg/ha in the carbofuran treatment, ca. 5637kg/ha in the diazinon treatment and ca. 4728kg/ha in the untreated plots. The magnitude of yield increase of garlics in the plots treated with carbofuran was attributable to positively stimulate the growth response of garlic plants as well as the control effects to onion maggots.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.5
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• pp.458-460
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• 2001

A 11-month-old infancy was referred for treatment of cleft palate. The patient's congenital deformities had included oronasal fistula on the soft palate and bifid uvula. Furrow double-opposing Z-plasty was performed under general anesthesia. However, postoperative bleeding developed at ward. Despite the pressure of operative wound, venous oozing continued and hemoglobin concentration and RBC were decreased (Hb: 5.5g/dL, RBC: $1.98{\times}10^6/mm^3$). The patient was pale and confused and transferred to Surgical Intensive Care Unit(SICU) We could not keep the peripheral venous line and there was a high risk of hypovolemic shock. Emergency transfusion was performed through the central femoral venous line and emergency operation for bleeding control was carried out. We explored the operation site and found bleeding point from the posterior pharyngeal wall. Electrocoagulation and surgicel packing were carried out and bleeding was stopped.