• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.5
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• pp.435-443
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• 2009

In this paper, we propose a microstrip slot antenna that works in Bluetooth, Zigbee, WiMAX and WLAN frequency bands($2.4{\sim}5.825\;GHz$). To get the wide bandwidth from the microstrip antenna proposed, we insert a pair of parastic strips along the feed line on the FR-4 dielectric substance(${\varepsilon}_r=4.8$). Furthermore, a simple geometrical rotation with quadrilateral slot is designed to maximize the bandwidth and to gain a wider frequency band than the conventional rectangular slot antenna. A additional design of the loop type is added to a cactus-shaped patched for 2.4 GHz ISM frequency band. The total measured bandwidth of the antenna is from 2.4 GHz to 6 GHz and the maximum gains of the antenna are 3.82 dBi, 4.48 dBi, 6.41 dBi and 6.65 dBi at the frequencies of 2.4 GHz, 3.5 GHz, 5.25 GHz and 5.77 GHz.

• Journal of the Korean Geotechnical Society
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• v.24 no.12
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• pp.5-12
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• 2008

The reinforced earth wall, which is able to improve the strength of soil highly, is required in case of supporting high surcharge load such as high speed rail way, high embankment road, and massive reinforced earth wall in a mountainous area. And also, it is continuously required that the method is able to minimize the amount of excavated soil on account of environmental issue, boundary of land, etc., on excavation site. However, because the required length of reinforcement should be $60{\sim}80%$ of the height of reinforced earth wall for general reinforced earth wall, in fact the reinforced earth wall is hardly applied on the site of cut slope. In this paper we studied the design and construction cases of hybrid reinforcement retaining wall system combined with steel strips and soil nails, connecting the reinforced earth wall reinforcements to the slope stability reinforcements (soil nails) to ensure sufficient resistance by means of reducing the length of reinforcements of reinforced earth wall. And the feasibility of hybrid reinforcement retaining wall system, suggested by real data measured on site, is also discussed.

• Parasites, Hosts and Diseases
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• v.27 no.1
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• pp.9-14
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• 1989

Enzyme-linked immunoelectrotransfer blot (EITB) using crude worm antigen of adult Paragonimus westermani was performed for human patients sera to identify the species-specific components. Crude antigen was obtained by homogenizing and centrifuging 24-week old adult worms at 10,000 rpm for 60 minutes in phosphate buffered saline (PBS, PH 7.2) containing: Phenyl methyl sulfonyl auoride (PMSF). Gradient sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) was performed and blotted electrophoretically onto a sheet of nitrocellulose paper. The sheet was cut into strips and exposed to sera diluted 1 : 200 with PBS. SDS-PAGE showed 26 protein bands ranging 229 to 10 kDa. Of them 229, 91, 60, 50, 35∼31, 27, 25, 21, 17, 11 and 10 kDa components showed positive reaction with serum antibody of patients with p. westermani. Sera of patients infected with Clcnorchis sinensis reacted with 35∼31, 19, and 11 kDa bands. Human sera from cysticercosis and diphyllobothriasis cases showed non-specific cross reactions with 229, 35∼31, 27, 25 and 17kDa bands. Protein bands of 91, 60, 21 and 10kDa showed strong positive reaction without cross reactions with sera from other helminthic infections.

• Elastomers and Composites
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• v.42 no.1
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• pp.20-31
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• 2007

Material characteristics and lifetime evaluation are very important in design procedure to assure the safety and reliability of the rubber components. In this paper, the NBR compound was prepared by sulfur-cure system, and was used in predicting the lifetime of rubber gasket made by the compound. The accelerated material aging was investigated at different temperatures at 120, 140 and $160^{\circ}C$ and aging time from 3 hours to 600 hours at 5, 6, 7 vol %. of $H_2SO_4$ concentrations The rubber strips were placed in acid solution using pyrex g1ass tube. Both ends of pyrex g1ass tube were sealed to avoid evaporation of solution during heating at given time. The material test and accelerated acid-heat aging test were carried out to predict the useful life of NBR rubber gasket for a fuel cell stack. In order to investigate the effects of acid-heat aging on the properties of the NBR, tensile strength, elongation at break, hardness and crosslink-density were measured. The tensile strength decreases as the $H_2SO_4$ concentrations and temperature increase. Results were evaluated using Arrhenius equation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.4
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• pp.679-687
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• 2017

In this paper, a microstrip-fed triple-band monopole antenna with DGS (Defected Ground Structure) for WLAN/WiMAX applications was proposed. The proposed antenna is based on a microstrip-fed structure, and composed of two strip lines and DGS structure and then designed in order to get triple band characteristics. We carried out simulation about parameters. Adjusted the position and length of the two strips and three slits, we get the optimized parameters. The proposed antenna is fabricated on an FR-4 substrate of which the dielectric constant is 4.4, and its overall size is $34mm(W_1){\times}34mm(L_1){\times}1.6mm(t)$, and its proposed antenna size is $17.0mm(W_6){\times}30.75mm(L_3+L_4+L_9)$. From the fabricated and measured results, return loss of the proposed antenna satisfied return loss -10dB bandwidth 360 MHz (2.335~2.695 GHz), 645 MHz (3.37~4.015 GHz) and 1,770 MHz (5.14~6.91 GHz). And measured results of gain and radiation patterns characteristics displayed for operating bands.

• Korean Journal of Heritage: History & Science
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• v.56 no.2
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• pp.100-121
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• 2023

This paper examines the interior settings of a chamber and of a temporary place of enshrinement at Yeonghuijeon (永禧殿, Hall of Eternal Happiness), the representative official portrait hall in which portraits of early and late Joseon kings were enshrined. Also, it discusses the features of the Five Peak screens used therein. The physical environment of a chamber at Yeonghuijeon mainly consisted of a four-panel folding screen with a painting of Five Peaks and a large wooden platform, which was adorned with dragon and lion patterns and attached to lotus-leaf column balustrades. The Five Peak screen was installed on a large platform in the shape of ⊓, spreading across the second and third panels on the back and folding out on the first and fourth panels on the right and left sides. When a portrait was enshrined in a temporary place, a simpler and smaller platform with railings was used. A four-panel folding screen of the Five Peak painting was installed in the same way as in a chamber, but was unfolded around a smaller platform behind it. A royal portrait was displayed in each chamber, whereas a case in which a portrait was rolled up was put on the smaller platform in a temporary place. The Five Peak screens for a chamber and a temporary place were all large four-panel folding screens with two wide panels in the middle and two narrow panels on each side, and only strips of silk were mounted on the four edges of the screens without additional wide lower-side mountings. While screens for the chamber used patterned silk for mounting and white paper for backing on screen frames, screens for the temporary place used plain silk and recycled failed test papers for mounting and backing, respectively. By examining records in the literature on the Five Peak screens for Yeonghuijeon, this paper highlights two Five Peak screens, both of which lost their provenance from the hall. The structures of the two screens reflected the way they were to be installed at the hall. Furthermore, this paper assumes that a Five Peak screen, which had been unfolded on the throne in the main hall of Changdeokgung Palace after the 1960s, was produced in 1858 for the purpose of temporarily enshrining King Sunjo's portrait due to the fact that failed test papers of the 1840s were laid taut over the frame.