• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.7
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• pp.113-120
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• 2021

An experimental device was designed to control the opening of a damper via operating the folding blade drive of the device and to control the amount of air flowing through the damper. In addition, an inverter was installed in the blower to control its fan rotation speed and hence the amount of air flowing through the damper. An experimental study was conducted on the opening of the folding blade damper and changes in the rotational speed of the blower. From the results, the theoretical air volume of the folding blade damper and experimental air volume were observed to be in good agreement within an error range of ±3%. As the mass flow rate of the air passing through the folding blade damper increases proportionally with the changes in damper opening and fan rotation speed, the performance of the damper can be controlled proportionally. The mass flow rate was also observed to increase linearly; therefore, the mass flow rate of the air passing through the folding blade damper increases proportionally with changes in the rotation speed of the blower, such that the performance of the damper is proportional to a constant air volume even with varying rotation speeds of the blower.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.149-157
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• 2003

This study focused on relationships between Pb and Cd concentrations and the difference of success reproductive progress in urban (Seoul) and industrial complex (Ansan) areas. Results of the Pb analysis for the feral pigeons from Seoul (egg contents:1.64 $\mu\textrm{g}$ wet $g^{-1}$, adults in bones: 29.5 $\mu\textrm{g}$ wet $g^{-1}$ and the Ansan industrial complex (egg contents: 1.13 $\mu\textrm{g}$ wet $g^{-1}$, adults in bones: 10.5 $\mu\textrm{g}$ wet g-1) showed that the Pb level of eggs and adults is significantly different between the two colonies (p<0.05). Cd concentrations in liver and kidneys of adult pigeons were also significantly different between Seoul(liver: 0.24 ${\mu}g$ wet $g^{-1}$, kidney: 1.05 $\mu\textrm{g}$ wet $g^{-1}$ and the Ansan (liver: 0.14 $\mu\textrm{g}$ wet $g^{-1}$, kidney: 0.43 $\mu\textrm{g}$ wet $g^{-1}$ colonies (P<0.05). Clutch size of Feral Pigeons living in Seoul was similar between the two colonies, 1.9$\pm$0.3 in Seoul and 2.0$\pm$0.0 in Ansan. The length, breadth, and thickness of eggs were not significantly different between the two colonies (p>0.05). Incubation period in Seoul (17.8 days) did not differ from the Ansan (17.4 days). No difference in growth rate (body weight, wing length, and tarsus length) was found between the two test groups (p>0.05). In Seoul, 65.2% were hatching, and 42.1% fledging. The Proportion of hatching and fledging in the Ansan was 60.7% and 45.0%, respectively. The significant differences between the two colonies for reproductive sucess were not found (p>0.05). With regard to the reproductive effects to the heavy metals, the Pb and Cd concentrations feund in the two colonies were not as high as those considered in results of toxic effects in other species.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.74-85
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• 1995

A study was conducted to provide some basic data for controlling the Mulberry scale insect(Pseudaulacaspis pentagona T.). Experiments were carried out with checking their field-life, and a few selected insecticides were tested when mulberry leaves were not in use. About 57% of female were survived from the overwintering attached to the bark. Over 80% of the scale were distributed within the range of 30cm from the base of each stem. One hundred percent and 96.7% of eggs were hatched under 25$^{\circ}C$ and 27$^{\circ}C$ respectively. Eighty percent of pupae emerged both under 25 and 27$^{\circ}C$. The Mulberry scale require about 33 days under 25$^{\circ}C$ and 30 days under 27$^{\circ}C$. This species had 2 generations each year in mulberry field in Suwon. Overwintered as a mated female only. Oviposited about 170 eggs under their scale starting from the late April (in 1994) through the mid May (in 1993). Phenthoate EC sprayed in the mid June against the larvae was very effect with over 96% of control value.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.217-231
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• 2020

In 2019, the sex pheromones of Spodoptera frugiperda were used to examine moth trapping in cornfields in Gochang, Korea. Four types of traps were prepared, two funnel-types and two delta-types, each baited with 300 or 1000 ㎍ of a two-component (2C) blend of synthetic sex pheromones [100% (Z)-9-tetradecenyl acetate (Z9-14Ac) and 2% (Z)-7-dodecenyl acetate (Z7-12Ac)]. The greatest number of S. frugiperda were captured in the 300 ㎍ funnel-type trap (first catch: August 6). Large numbers of Mythimna loreyi (a non-target) were also caught in the funnel-type traps. Two wing-type traps were baited with 1000 ㎍ of the 2C blend or a four-component (4C) blend [100% (Z)-9-tetradecenyl acetate, 8% (Z)-11-hexadecenyl acetate (Z11-16Ac), 2% (Z)-7-dodecenyl acetate, and 1% (Z)-9-dodecenyl acetate (Z9-12Ac)] and the capture efficiency was assessed. Low numbers of S. frugiperda were captured regardless of the blend, and more M. loreyi were captured using the 4C blend. The two intraspecies groups clustered separately in a phylogenetic tree constructed using partial sequences (1004 bp) of cytochrome c oxidase subunit 1 (CO1). Of the 70 S. frugiperda captured in the pheromone traps, 66 belonged to CO1-RS (CO1 rice-strain) and 4 to CO1-CS (CO1 corn-strain). Twelve consistent single nucleotide polymorphisms (SNPs) were identified in CO1 between the CO1-RS and CO1-CS groups of S. frugiperda. Of the 73 S. frugiperda, 4 had the same SNP pattern as the CO1-CS group (including the corn strain) and 69 had the same SNP pattern as the CO1-RS group (including the rice strain).

• Journal of Korean Society of Forest Science
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• v.2 no.1
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• pp.59-65
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• 1962

The objects of this experiment are to find out the local variation of the Dendrolimus Spectabilis Butler, of which sample was first collecteted 15 bodies of male and 35 bodies of female adult at Suwon area. the wing veins and the scale shape have been observed through the microscope (100) and the scale size (from the bottom of the scale to the top of the lobe) has also been measured by the micrometer. The results of this experiment are as follows: 1. There is nodifference between the venation of the male body and that of the female body. Also we can not find any differences between the right and the left wing, and between each body. The fore wings consit of 13 longitudinal veins and the only one "V" shape cross vein which is between the 5th and 6th vein. The hind wings consist of 9 longitudinal veins and the only one "V" shape cross vein which is mentioned above. 2. The scale types are divided into 4 Groups in its shape. (A) The scales of I Group are short and the lower parts of them almost look like a circle, having a small projection at their bottom. The upper parts of them have 2 or 10 lobes. We can find the lobes with fine hairs or the lobes without them at the top of the scales. (B) The scales of II Group are longer than that of I Group. The shape of the lower parts of the scales is similar to that of I Group. The upper parts of the scales have 2 or 10 lobes. (C) The scales of III Group are long and almost alike in a long wedgeshape. The upper parts of the scales have 2 Or IO lobes and we can find long fine hairs at the top of each lobe. (D) The scales of IV Group are long and the shape of the lower parts of the scales is similar to that of III Group. The lobes are short and not sharp. We can find 2 or 9 lobes. 3. The scales of I Group and II Group are distributed on the whole surface except on the outer margin. The most scales of III Group are distributed on the wing base. The scales of IV Group are distributed on the outer margin only. The scales with 4 or 5 lobes are most widely distributed not considering their Group or distributing parts. 4. In I Group the variation of the scale length become gradually greater as the number of the lobes are increasing. In II, III, IV Group, however, the variation of the scale length is in direct opposition to the above mentioned. The variation of the scale width becomes pretty small in any Groups and the scale width become wider as the number of the lobes are increasing. 5. The source of the wing colouration is pigmnetal colour, and the wing colouration is expressed by the amount of brown and white scales.

• Korean Journal of Plant Taxonomy
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• v.39 no.1
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• pp.12-23
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• 2009

To verify hybridity of Asplenium castaneo-viride, external morphology, spore morphology, anatomy and chromosomes of the species and of the two presumed parental species, A. incisum and A. ruprechtii, were examined. A. castaneo-viride usually had 1-pinnately divided frond. However, some individuals had almost simple fronds with pinnatisect basal parts similar to A. ruprechtii, while others had fronds similar to A. incisum in having oblanceolate blades and basal pinnae with triangular, 2-3 lobed apices. On the surface of the spores, sculpturing consisted of folds that were usually prominent; forming long wings, and irregular or incomplete reticulation. However, reticulation patterns varied among species. A. castaneo-viride showed a wide range of variation from sparse to dense patterns, whereas A. incisum showed only from sparse to intermediate patterns. A. ruprechtii showed from intermediate to dense patterns. The spore size of A. castaneo-viride was $54.63{\mu}m$, larger than other two species ($47.81{\mu}m$ in A. incisum and $44.22{\mu}m$ in A. ruprechtii). The level of undulation of epidermal cell wall was also different. A. incisum had the most shallowly undulated wall, and A. castaneo-viride had a pattern intermediate between the two presumed parental species. This same patterns was recognized in the density of stomata. The density of $45.91/mm^2$ in A. castaneo-viride was intermediate between the two presumed parental species ($67.00/mm^2$ in A. incisum, and $37.86/mm^2$ in A. ruprechtii). Chromosome number was constant (2x =2n = 72) as in A. incisum and A. ruprechtii. However, A. castaneo-viride showed a different ploidy level. The populations of Mt. Mai (Jeonbuk province) and Mt. Duryun (Jeonnam province) were diploid (2n = 72) which is a new record for this taxon, whereas the population of Mt. Buram (Seoul) was tetraploid (2n = 144). Conclusively, A. castaneo-viride was revealed to be a hybrid of A. ruprechtii and A. incisum based on evidence involving leaves, spores, epidermal cells, stomata and chromosome number.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.121-127
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• 1972

The present paper deals with the results of the comparative morphology on the urohyal bones on the right-eye flounders, pleuronectidae fishes in Korean waters. The results obtained are as follows : 1. The position of the tip of sciatic part is quite different depending on the genera and species of the fishes. The sciatic part of the genera, Platichthys and Cleisthenes, is very short extending to the middle portion of the main part. In the fishes of Eopsetta and Tanakius, it is also very short extending to the anterior 1/3 of the distance from the tip of main part. The fishes of Verasper and Dexistes have a short sciatic part which extends toward the posterior 1/4 of the distance from the tip of main part. The fishes Of Limanda, Clidoderma, Glyptecephalus and Microstomus have a long sciatic part which extends as long as the main part. However, those of Kareius and Pleuronichthys have a very long sciatic part extending twice long as the main part. The tip of sciatic part of the fishes belonging to Eopsetta, Verasper, Limanda, Platichthys, Tanakius and Glyptocephalus is a truncate form. It is pointed upward in the fishes of Kareius, Pleuronichthys, Clidoderma and Microstomus, but pointed forward in Cleisthenes and Dexistes. 2. The size and form of the cardiac apophysis vary with the developmental grades of the urohyal bone. The fishes of Eopsetta, Verasper, Platichthys, Tanakius, Kareius and Dexistes possess relatively large apophyses and those of Pleuronichthys and Clidoderma have small apophyses. Intermediate size of the apophysis is found in the fishes of Limanda, Microstomus and Cleisthenes. A long and barlike apophysis is found in Glyptocephalus. Three kinds of the cardiac. apophysis are found in the fishes examined, i. e., lateral wing in Eopsette, Verasper, Limanda, Platichthys, Tanakius, Glyptocephalus, Kareius, Pleuronichthys and Clidoderma, pointed forward in Microstomus and Cleisthenes, and truncate with a well-developed inner ridge type in Dexistes. 3. The angle of the main part and sciatic part varies from 30 to 60 degrees in the fishes studied except for the fishes of Pleuronichthys, Clidoderma and Microstomus which show a semi-elliptical form.

• Korean Journal of Plant Taxonomy
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• v.33 no.3
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• pp.227-253
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• 2003

Morphological characters of C. kobomugi, C. gibba, C. echinata. C. remotiuscula. C. maakii. C. curta, and C. loliacea of genus Carex were rexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning electron microscope(SEM) and a light microscope(LM). Morphological characters. such as length and width of stem and leaf, sheath, bract, spike, scale, perigynium, beak of perigynium, length of spike peduncle, size, and frequency of stomatal complex of leaf, number of bract, shape of stem transection, scale and apex of scale, beak and base of perigynium, achene, epidermal cell and cell wall of perigynium, achene, leaf epidermal patterns (fundamental epidermal cell and cell wall, silica body, subsidiary cell), hair, papillae, prickle present/absent of perigynium and leaf were useful for the identification of observed seven taxa. Examined six taxa of section Macrocephalae, Gibbae, Stellulatae, Elongatae, Ovales, and Heleonates were distint from each other with respect of length and width stem, leaf, bract, perigynium, perigynium beak, lenght of spike peduncle, perigynium, and leaf. A key based on data was presented here.

• Composites Research
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• v.32 no.1
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• pp.65-70
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• 2019

The aircraft composites wing parts are usually integrated with adhesive or fastener. These laminated composites have weak interlaminar strength, which can lead to delamination. In order to compensate the disadvantages of laminated composites, it is possible to improve the strength, durability, shock and fatigue resistance by reinforcing the fiber in the thickness direction. In addition, using a single structure near-net-shape saves the manufacturing time and the number of fasteners, thus can reduce the overall cost of the composite parts. In this study, compression test, tensile test and open-hole tensile test are carried out for three structural architecture of 3D (three-dimensional) textile preforms: orthogonal(ORT), layer-to-layer(LTL) and through-the-thickness(TTT) patterns. Among these, the orthogonal textile composite shows the highest Young's modulus and strength in tensile and compression. The notch sensitivity of the orthogonal textile composite was the smallest as compared with UD (unidirectional) and 2D (two-dimensional) fabric laminates.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.681-686
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• 2011

The aim of this study was to investigate the distribution of soil biota across forest types and soil depths in Gwangneung Experimental Forest. We selected 5 sites, which are 3 deciduous- and 2 coniferous forests. The abundance of microflora in these areas was analyzed by the phospholipid fatty acid (PLFA) indicators, and the density of mesofauna was measured by the abundance of nematodes and microarthropods. The abundance of soil microflora was higher in the A layer than in the B layer based on the PLFA indicators, but there were no differences between deciduous and coniferous forests. Average density of nematodes was higher in the A horizon than in the B horizon. The density of fungivorous nematodes was higher in the deciduous forests. Mean densities of Collembola and Oribatida were 44% and 42% of microarthropods in soil samples, respectively. The results of microbial PLFA indicators were significantly correlated with the density of their consumers, which reflected that the food web in fungi- and bacteria-based soil developed in this forests. This study suggested that the distribution of soil organisms largely separated by soil depths and was slightly affected by the forest type in the Gwangneung Experimental Forest.