• Journal of the Korean Society of Safety
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• v.31 no.3
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• pp.8-15
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• 2016

The purpose of this study is to design a model with the structural stability so as not to lose the operational function due to structural plastic or fail of a sliding blast door by blast pressure to this aim, a numerical simulation was performed using full-size experiments and M&S (Modeling & Simulation) of the sliding blast door. The sliding blast door ($W3,000{\times}H2,500mm$) under the blast load is in the form of a sliding type 2-way metal grill, which was applied by a design blast pressure (reflected pressure $P_r$) of 17 bar. According to the experimental results of a real sliding blast door under blast load, the blast pressure reached the sliding blast door approximately 4.3 ms after the explosion and lasted about 4.0 ms thereafter. The maximum blast pressure($P_r$) was 347.7 psi (2,397.3 kPa), it is similar to the UFC 3-340-02 of Parameter(91 %). In addition, operation inspection that was conducted for the sliding blast door after real test showed a problem of losing the door opening function, which was because of the fail of the Reversal Bolt that was installed to prevent the shock due to rebound of the blast door from the blast pressure. According to the reproduction of the experiment through M&S by applying the blast pressure measurement value of the full-size experiments, the sliding blast door showed a similar result to the full-size experiment in that the reversal bolt part failed to lose the function. In addition, as the pressure is concentrated on the failed reversal bolt, the Principal Tensile Failure Stress was exceeded in only 1.25 ms after the explosion, and the reversal bolt completely failed after 5.4 ms. Based on the result of the failed reversal bolt through the full-size experiment and M&S, the shape and size of the bolts were changed to re-design the M&S and re-analyze the sliding blast door. According to the M&S re-analysis result when the reversal bolt was designed in a square of 25 mm ($625mm^2$), the maximum pressure that the reversal bolt receives showed 81% of the principal tensile failure stress of the material, in plastic stage before fail.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.3
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• pp.12-21
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• 2012

The proximities of Cheonggye creek was a maj or space for the gathering of large populations from the past times and it is also a place containing the joy, anger, sorrow, pleasure and lives of the citizens. The Cheonggye creek which flowed downtown of Seoul throughout many historical events had disappeared into history completely in the modernization process due to the contamination with life sewages and overflow. However, the city authority of Seoul decided to restore it to its shape before covering the creek by means of dismantling the old elevated ways in Cheonggye creek in line with the Large Scale City Movement Project to revive the grey city and to improve the quality of the city landscape in 2002. The cultural space was created by activating the old town sphere in Cheonggye Creek and the amenities of the giant city was improved by the cultural and natural wave created along the creek. In addition, the educational opportunity has been provided to the citizens by means of reviving its historical nature. The design and cultural value of the Cheonggye Plaza were restored for the mean time and the urban environment requested during modem times was established. The Cheonggye Plaza which heightened the balanced development in Seoul which has been developed in an unbalanced way by dividing into northern and southern area of the river is very meaningful in the viewpoint of the landscape architect who designs the urban space. The re-birth as a cultural space of downtown owing to the efforts of the said cultural catalysts is meaningful.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.684-692
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• 2016

In the manufacturing process of the LQFP/TQFP (Low-profile Quad Flat Package/Thin Quad Flat Package), the requirement of a 3 dimensional inspection is increasing rapidly and a 3D inspection of the shape of a chip has become an important report of quality control. This study developed a 3 dimensional measurement system based on PMP (Phase Measuring Profilometry) for an inspection of the LQFP/TQFP chip and image processing algorithms. The defects of the LQFP/TQFP chip were classified according to the dimensions. The 2 dimensional optical system was designed by the dorm illumination to achieve constant light distribution, In the 3 dimensional optical system, PZT was used for moving 90 degree in phase. The problem of 2 ambiguity was solved from the measured moir? pattern using the ambiguity elimination algorithm that finds the point of ambiguity and refines the phase value. The proposed 3D measurement system was evaluated experimentally.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.5
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• pp.711-720
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• 2009

Leaf fibers have many good properties; they are strong, long, cheap, abundant and bio-degradable. Since they, however, contain a great quantity of non-cellulose components, they have been used for the materials of mats, ropes, bags and nets rather than those of clothing. In this study, we investigated the characteristics of leaf fibers in order to promote the use of leaf fibers for the materials of clothing as well as develop the high value-added textile fibers. Leaf fiber plants including New Zealand Flax, Henequen and Banana plant, which have various nature and shape, were used. New Zealand Flax and Henequen leaves were cut from lower part of plants. Banana leaves and pseudo-stems were peeled and cut from the stem of Banana plants. First, the thin outer skins like film of leaves, veins and stems were removed before retting. The chemical retting had been processed for 1hour, at 100 in 0.4% $H_2SO_4$ aqueous solution(liquid ratio 50:1). Then, the retted leaf fibers had been soaked for 1hour, at room temperature in 0.5% NaClO solution(v/v) to remove the miscellaneous materials. We investigated the physical characteristics of three leaf fibers including the transversal and longitudinal morphology, the contents(%) of pectin, lignin and hemicellulose, the length and diameter of fibers, the tensile strength of the fiber bundles, and the fiber crystallinity and the moisture regain(%). The lengths of fiber from three leaf fibers were similar to their leaf lengths. The fiber bundles were composed of the cellulose paralleled to the fiber axis and the non-cellulose intersecting at right angle with the fiber axis. The diameters of New Zealand Flax, Henequen and Banana fibers were $25.13{\mu}m$, $18.16{\mu}m$ and $14.01{\mu}m$, respectively and their tensile strengths were 19.40 Mpa, 32.16 Mpa and 8.45 Mpa, respective. The non-cellulose contents of three leaf fibers were relatively as high as 40%. If the non-cellulose contents of leaf fibers might be controlled, leaf fibers could be used for the materials of textile fiber, non-wovens and Korean traditional paper, Hanjee.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.47-51
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• 2000

A some of synthesized 2,3-dihydro-2,2,4,6,7-pentamethylbenzofuran-5-yl substituents in 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one derivatives as substrates were found to show herbicidal activity against rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) with post emergence under submerged conditions. The substrate with $R_{1}$=methyl substituents, $1{\sim}5$ showed the higher herbicidal activity to the seed, 3 leaf stage of rice plant and barnyard grass. The structure activity relationships (SARs) on the herbicidal activity of $R_{1}$ and $R_{2}$ on the azomethine bond in substrate were analysized. In the condition of $R_{1}$ groups are same, the herbicidal activity against 3 leaf stage of rice plant were governed by the optimal hydrophobicity $(logP)_{opt.}=4.57$. Whereas, in the case of barnyard grass, the herbicidal activities were largely dependent upon the steric effect, $B_{2}$ constant than hydrophobicity. In order to take the selective herbicidal activity between rice plant and barnyard grass, it is assumed that the (S) should be a round shape with higher hydrophobicity (logP>4.57) than optimal value. Also, the $R_{1}$ groups must be small and the $R_{2}$ groups are advisable to be unsaturate.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.1
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• pp.159-169
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• 2012

Seokgasan(石假山) is originated in Goryeo, is a Korean traditional technique handed down to Joseon and Seokgasan is the Korean creative culture of gardening by artificial stones, which replicates small artificial mountain of natural landscape in the garden. The object of this study is Seokgasan made by Seong-im(成任), who was a civil minister in Joseon and lived from 1421 to 1484, in his residence located in Inwang Mountain, Hanyang and the purpose of this study is to investigate the historical meaning and symbol of Seokgasan made by Seong-im on the base of the relative old literatures and embody its shape and structure. According to the result of this study on Seokgasan of Seong-im, it can find out some facts as follows; Seokgasan of Seong-im in the early Joseon succeeded to the structural form of Seokgasan of the artificial rock mountain type connected pond, which was made-up firstly in the garden of the Palace of Manwoldae in the Middle Goryeo, and it was called firstly as 'Seokgasan' in the garden of Seong-im's house. Seong-im's Seokgasan in the early Joseon had more concentrated philosophical meanings, including the idea of taoist immortal, than those in the Goryeo dynasty and was be emblematic of an imaginative space. Also there were lots of gardens modeled on the famous mountains and famous lakes in China much the same as the Goryeo dynasty. In addition, there was an exceptional purpose for building Seokgasan which could not be found in the Goryeo dynasty. That was practicality for emotional stability and cure. Seong-im's Seokgasan is record-relics with high value of landscape architecture history, which can identify its historical meanings, shapes and structural frames succeeded from the Goryeo dynasty.

• Journal of Korean Society of Rural Planning
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• v.26 no.2
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• pp.107-116
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• 2020

Up to date, the majority research on the major landscape elements in organic farming has been mainly focused on the practice of seeking efficiency. The problem is that this type of study contributes to polluting the agricultural environment and damaging the ecological circulation system. As an alternative, there is a growing body of research on organic farming, but it is not widely applied that research on how to manage the landscape considering the scenic characteristics of farming villages practicing organic farming. Therefore, this study was carried out in the conservative aspects of rural landscapes in order to effectively manage the landscape of organic agriculture and, intended to be used to maintain and preserve natural and ecologically harmonious landscapes by deriving management methods suitable for landscape elements targeting the major landscape elements of the organic farming complex. To carry out, this study performed the experts survey which is composed of 13 major landscape elements, including rice paddies and fields, monoculture and diverse crops, dirt roads, windbreak trees, accent planting, dum-bung(small pond), natural small river, natural waterways, plastic film houses, one-storied houses, and pavilion. As a result, Farm land was formed in a square shape, concentrated in an independent space, planted companion plants around the crop, and covered with plants to manage the borders. As for the surrounding environment, it was analyzed that the aspart road system circulating through the village, the evergreen broad-leaved windbreak forest around the cultivated land, and the accent plant located at the entrance of the village were suitable. The hydrological environment consists of Round small pond made of stone in an open space, natural rivers around the village, and natural channels around the farmland, and The Major facilities are suitable for greenhouses that are shielded by plants in independent regions, and wooden duck houses located inside the cultivation area are suitable and The settlement facilities were analyzed to be suitable for single-story brick houses located in independent residential areas, pavilion located with greenery in the center of the village, and educational spaces shielded with wood from arable land. If supplementary evaluation criteria suitable for the management of organic farming landscape are additionally supplemented based on the results derived from this study, It is expected to enhance the landscape value of ecologically superior organic farming.

• Archives of Plastic Surgery
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• v.34 no.1
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• pp.37-43
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• 2007

Purpose: Photogrammetry has been introduced as an alternative to direct measurement to obtain facial distances for a variety of anthropometric applications. The aim of this study is to establish morphological and functional value of an eye in Korean youths using specially designed computer software with digital photographic images. Methods: Authors measured anthropometry of an eye in Korean youths 1,449 individuals(622 males, 827 females) and analyzed stastically them. Results: The mean measurements are as follows. The diameter of cornea was $11.6{\pm}0.9mm$ in males and $11.3{\pm}0.9mm$ in females. The vertical dimension of palpebral fissure was $7.4{\pm}1.7mm$ in males and $8.2{\pm}1.6mm$ in females. The intercanthal width was $35.8{\pm}3.2mm$ in males and $34.4{\pm}2.9mm$ in females. The biocular width was $90.4{\pm}5.7mm$ in males and $87.4{\pm}5.3mm$ in females. The endocantion-superior margin of palpebral fissure distance was $12.7{\pm}1.4mm$ in males and $11.6{\pm}1.4mm$ in females. The horizontal dimension of palpebral fissure was $28.5{\pm}2.2mm$ in males and $27.4{\pm}1.9mm$ in females. The slant of palpebral fissure was $10.7{\pm}2.6^{\circ}$ in males and $11.3{\pm}3.0^{\circ}$ in females. The height of upper eyelid was $10.6{\pm}2.3mm$ in males and $10.7{\pm}2.3mm$ in females. The width of double fold was $2.0{\pm}0.7mm$ in males and $1.9{\pm}0.6mm$ in females. A double fold was seen in 21.9% of males and 44.9% of females. The most frequent shape of the double fold was type IV. The most common type of epicanthal fold was type III in both males and females. Conclusion: Photogrammetic measurement of large population using specially designed software could offer reliable data and these data could be useful reference for preoperative consultation, surgical planning and anthropometic study of eye.

• 한국해양학회지
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• v.29 no.2
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• pp.152-163
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• 1994

The characteristics and fluctuations of structures and spatial distributions of warm eddies (anticyclonic eddies) in the southwestern part of the East Sea (the Japan Sea) are discussed based on the data gathered y the Fisheries Research and Development Agency, Korea from 1967 to 1968. The warm eddies existed very often in the southwest of the Ullung Island. The warm eddies are elliptical in shape and the mean size is about 130 km in diameter. Bimonthly distributions of warm eddies, the largest value of observed frequency and diameter in August and the least in June, indicate that the generation of the warm eddy is related with the development of the East Korean Warm Current. The warm eddies move west, north or southward with 0.80∼2.50 cm/sec or stay over a few months at the same place southwest of the Ullung Island. Movement of warm eddies may be influenced by the neighboring currents, the Rossby wave and the topography. The relationship between the position of warm eddies and the bottom topography suggests that the development and the movement of warm eddies are controlled by the Ullung Basin. The warm eddies should be divided into two groups. One group is the shallow warm eddy with strong baroclinic characteristics and the other is the deep one with strong Barotropic characteristics. The shallow group seems to be closely related with positive values (in summer) of the sea level difference between Pusan and Mozi (the Tsushima Current), while the deep group has no relation with that.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.1
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• pp.1-12
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• 1994

Stow-net is originally spreaded with a lifting beam and a depressing beam. The net is improved by using canvas-made spreading devices by Mr. Han and his colleagues in the beginning of 1980's. The net is improved again by changing the partial shape of netting and arrangement of net pendants so as to be fitting with the actual performance of the net by Dr. Lee and his colleagues since 1988. The author studied to compare the fishing efficiency of those two kinds of nets(The former which was improve by Mr. Han is expressed as a traditional net and the latter improved again by Dr. Lee is expressed as an improved net in the present study). Twenty-one stow-netters concerned with the present study were selected among those based on the Port of Inchon, and were classified into two groups-eleven of them are a traditional net used group and ten are an improved net used group. The data on the fishing operation from August 1992 to March 1993, including the catch, the price of sell, the fishing operated times in every cruise and the fished position noticed by every stow-netter were offered by concerned stow-netters. From the data the times of operation, catch and value in every cruise were extracted and analyzed. The results obtained can be summarized as follows: 1. The times of operation in cruise were 13.7 by the traditional net used group and 12.7 by the improved net used group. 2. The mean catch per cruise showed 10.1M/T in the traditional net used group and 12.2M/T in the improved net used group, so the latter showed 21% better. 3. The mean catch per operation showed 0.7M/T in the traditional net used group and 0.9M/T in the improved net used group, so the latter showed 28% better. 4. The rate of three important species(starks, hair tail and croakers) in the total catch showed 83%, and the catch showed greater by the improved net used group at the rate of starks 141%, hair tail 110%, croakers 107%. 5. The rate of three important species in the total price showed 82%, but the price of starks which occupied the biggest in catch showed merely 5%, then the economical efficiency appeared low. 6. The mean price per stow-netter and per operation showed about 20%, greater respectively by the improved net used group and the mean price per operation by two important species(hair tail and croakers) showed greater about 30% by the improved net used group.