• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.9
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• pp.886-894
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• 2014

A wideband bow-tie antenna fed by wideband microstrip-coplanar stripline(CPS) balun and band notch structures that can be applied to bow-tie antenna are proposed in this paper. In order to increase bandwidth, bow-tie radiators are reshaped so that the surface current flows continuously, and wideband impedance matching is achieved by adjusting strip width and spacing of CPS feeding line. The VSWR is measured as 2:1 over the wide frequency range of 2.3~12 GHz. The fabricated antenna size is $60mm{\times}60mm$. In order to achieve the band-notch function at WLAN(5.8 GHz), ${\lambda}/4$ folded-slits located ${\lambda}/4$ away from feeding point are utilized. To minimize the slit size, folded-slit type is adopted. The measured VSWR is 7:1 and gain attenuation is 14 dB at 5.8 GHz.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.400-403
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• 2002

The fundamental experiments for measuring soft x-ray characteristics from the vacuum capillary are described. These experiments were primarily performed in order to generate line spectra such as x-ray lasers. The generator consists of a high-voltage power supply, a polarity-inversion ignitron pulse generator, a turbo-molecular pump, and a radiation tube with a capillary. A high-voltage condenser of 200 nF in the pulse generator is charged up to 20 kV by the power supply, and the electric charges in the condenser are discharged to the capillary in the tube after closing the ignitron. During the discharge, weakly ionized plasma forms on the inner and outer sides of a capillary. In the present work, the pump evacuates air from the tube with a pressure of about 1 mPa, and a demountable capillary was developed in order to measure x-ray spectra according to changes in the capillary length. In this capillary, the anode (target) and cathode elements can be changed corresponding to the objectives. The capillary diameter is 2.0 mm, and the length is adjusted from 1 to 50 mm. When a capillary with aluminum anode and cathode electrodes was employed, both the cathode voltage and the discharge current almost displayed damped oscillations. The peak values of the voltage and current increased when the charging voltage was increased, and their maximum values were -10.8 kV and 4.7 kA, respectively. The x-ray durations observed by a 1.6 ${\mu}$m aluminum filter were less than 30 ${\mu}$s, and we detected the aluminum characteristic x-ray intensity using a 6.8 ${\mu}$m aluminum filter. In the spectrum measurement, two sets of aluminum and titanium electrodes were employed, and we observed multi-line spectra. The line photon energies seldom varied according to changes in the condenser charging voltage and to changes in the electrode element. In the case where the titanium electrode was employed, the line number decreased with corresponding decreases in the capillary length. Compared with incoherent visible light, these rays from the capillary were diffracted and diffused greatly after passing through two slits.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.84-90
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• 1986

An experiment was conducted to know the effects of planting dates (March 5, 15, and 25 and April 4) and transparent polyethylene (P.E.) film treatments(tunnel, tunnel slit, and mulch) on air and soil temperatures and growth and yield of a sweet corn variety, Great Bell. Maximum air and soil temperatures and minimum air and soil temperatures were greater at tunnel>tunnel slit>mulch in that order. Differences in maximum air and soil temperatures among the P.E. film treatments were much greater than those in minimum air and soil temperatures. However, when film was opened due to high air temperature over 40$^{\circ}C$ in the tunnel, air temperature was similar but soil temperature was lower com-pared to mulch. High temperature stress could be avoided in tunnel slit without opening film by increase in the number of slits. Cold damage of corn seedlings was avoided by tunnel and reduced by tunnel slit, and frost-damaged seedlings under the mulch were recovered in few days. The number of days from planting to silking was reduced as planting date delayed. At early plantings, tunnel enhanced early growth and silking, but it delayed at late plantings because tunnel was opened during the most of day time due to high temperature. Black streaked dwarf virus(BSDV) disease was more severe at early plantings and it was reduced in tunnel slit at late plantings because plants were grown under the film at the time of infection. The number of marketable ears was similar among all treatments except mulch at March 5 planting where BSDV was severely infected. Gross income was high in tunnel and tunnel slit at March 25 planting which had more larger marketbale ears and tunnel and tunnel slit at March 5 planting which had higher market price.

• Journal of the Korea Concrete Institute
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• v.22 no.5
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• pp.703-710
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• 2010

Reinforced concrete beams of existing structure often encounter insufficient shear problems for various reasons. Application of steel plates is one of widely used methods for shear strengthening of reinforced concrete beams that are insufficient of shear capacity. This study presents test results on strengthening shear deficient RC beams by external bonding of vertical and diagonal slit type steel plates with anchor bolt. Test parameters are width, interval, angle and length of slits with anchor bolt. The purpose was to evaluate the failure modes and shear capacities for RC beams strengthened by various slit type steel plates with anchor bolt. The results showed that the slit type steel plate specimens strengthened by adhesive bonding and bolting failed in shear fracture modes at maximum load. Flexural crack first occurred on the tension face of beam and then inclined cracks occurred on the shear span. Finally, slit type steel plates strengthened by adhesive bonding and fastening bolts managed to delay abrupt debonding and didn't detach fully from main body of RC beam.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.8
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• pp.930-936
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• 2007

In this paper, the high gain and broadband antenna operating for SDMB(Satellite Digital Multimedia Broadcasting) system is realized, The proposed antenna consists of the SAP(Shorted Annular Patch) structure, which inhibits surface-wave and the parasitic SAP element with spacing of $0.25 {\lambda}_0$ in order to improve gain, bandwidth and directivity. The RHCP(Right Hand Circular Polarization) is generated by two slits, which are made along the periphery of the circular patch at the diametrically opposite points, The simulated maximum gain of the proposed antenna is 12.6 dBi, which is better 5.22 dBi than maximum gain of the conventional microstrip patch antenna. The measured maximum gain is 10.5dBi at operating frequency 2.63GHz. Also, the measured impedance bandwidth$(VSWR{\leq}2)$ of the proposed antenna is $360MHz(2.488{\sim}2.848 GHz)$, which is better 300 MHz than the bandwidth of the conventional microstrip patch antenna. The measured HPBW(Half Power Beam Width) of the proposed antenna is $45.8^{\circ}$, and the measured FBR(Front to Back Ratio) is 15.49 dBi, The 3dB axial ratio bandwidth is 220 MHz$(2.54{\sim}2.76 GHz)$.

• The Research Journal of the Costume Culture
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• v.12 no.5
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• pp.859-879
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• 2004

As a result of research, the characteristics of the general costumes from the king Young-Cho period to the king Jung-Cho period in Genre Paintings of Mung-Hyun Oho, Yong Yun, In-Sang Lee, Hee-Eon Kang follows. First, the typical man wore his hair in a topknot(sangtu), and put on 'Bung-gu-ji', 'Lip', or a scarf on his head. The length of the 'Jeogori'(Korean traditional jacket) was long enough to cover the waist. Dress for work had side slits, and had half length sleeve Jeogori, and short pants looked like 'Jam-bang-i'. They went barefoot and wore 'Jipsin'(Korean traditional straw shoes). Dress for outdoor was 'Po' that knot at front of chest by band. 'Baji'(slacks) were with knot below knee, worn 'Hang-jun'(ankle band) and the width of slacks was suitable. They were 'Beoseon'(Korean traditional socks) and shoes. Second those in the upperc1ass and those in the military put on 'Mang-geon', 'Gat', 'Sa-bang-gan', 'Tang-geon', 'Bok-geon' on their head on a topknot. Most of them wore 'So-chang-i', 'Jung-chi-mag' or 'Do-po'. The length of Jeogori covered the waist or the hip and were tied with 'Go-rum'(ribbon). Baji was tied with Hang-jun and 'Dae-nim'. The waist of the slacks were tied with a dark colored waist-band and folded down their waist of slacks. They wore white color Beoseon and 'Hye' or dark color leather shoes. They wore 'Sup'(assistant of arm) for bow. It showed the lifestyle of the 18C with fan, 'Be-ru', 'Mug', 'Yun-jug', teacup, pot, etc. Third, child's hair was short or knotted to the back of the head. The length of Jeogori reached waist line, Git of Jeogori was 'Dunggurai-Kit'(shape of round) and other style Jeogori, which reached the hip line, had side-slit. Baji was tied with Dae-nim, and the width of the slacks is suitable. They hang 'Yum-nang'(Pocket). Final, most women worked outdoors wearing their hair in a high twisted style, or covered it with scarf. They wore Jeogori and 'Chima'(Korean traditional skirts), Bagi. They folded up the sleeves of the Jeogori. And they folded the 'Jambang-i-styled' pants to just above the knees, fastening at the waist. When they wore skirts, they also wore underpants under the skirt that went down to the knees. Most of them went barefoot and wore straw shoes, Jipsin. Through genre paintings, we can understand the ways and forms of our ancestor's clothing. And with our understanding, interest, and passion, we can be familiar with Hanbok in our daily life by succeeding and creating its peculiar style. And then we can promote the globalization of Hanbok.

• Journal of the Korean Society of Costume
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• v.50 no.3
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• pp.59-72
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• 2000

Dragon robe was defined as a robe on which the principal design consisted of dragon. Dragon patterns have been used on princess robes during T'and Dynasty. In Sung, Dragon-figured robes seem to have an Imperial prerogative. Yuan took over the use of robes with dragons patterns as a definite institition. Ming tried to reject all Yuan innovations, the dragon robe was retained as an unofficial court costume. The Emperor's semiformal robes which at first had four dragon medallions, later had twelve along with the 12 Symbols(십이장문). As Ch'ing dragon robes were only intended fro semiformal use. The Later Ch'ing robes date from after 1719, when the Ch'ien-lung(건륭) introduced 12 Symbols on Ch'ing robes. The Ch'ien-lung laws were disobeyed, notably the ones that specified the number of claws on the dragons. THe Emperor's dragon robe, lung-p'ao, (용포) was described as bright yellow in color, having four slits and horsefoof cuffs. The basic pattern consisted of nin dragons, in addition it had 12 Symbols. The elaborate textile techniques reached their peak in Ch'ing Dynasty-with its Weaving and Dyeing Office in Peking, and this factories at Hangchow(항주), Soochow(소주), and Naking(남경) -helps to explain why the decay of the Ch'ing bureaucracy hastended the decline of dragon robes. In the Ch'ing Dynasty tow terms were used for dragon robe, depending on the number of claws on the dragons. Those with five-clawed dragons were called lung-p'ao, while those with four-clawed dragons were called mang-p'ao(망포). The Court felt compelled to take corrective meausres. It decreeed that Ninisters of State and other officials, who had been bestowed five-clawed lung dragons, must take out one claw. Finally, the sale of ranks and the attendant privilege of wearing dragon robes gradually increased during the 18 th century, reaching its height in the 19 th century, Finally, after the Taiping Rebellion, when the Imperial Treasury was depleted by the wholesale destruction of revenue-producing lands, the Chinese government came to depend on such sales as an important source of revenue and the practice became even more widespread. The ensuing mass production of dragon robes, and the necessity of conforming to the fairly rigid basic pattern established in 1759, resulted in marked deterioration of workmanship, and a comparative monotony of decoration. The patterns on the dragon robes slight changes continued to be made in the ways of representign them. The li shui (입수) portion at the base of the robe become inreasingly wider throughout the 19th century. The background became cluttered with symbols of good fortune, scattered among the clouds and waves. As a result of all this extraneous decoration, the dragons were so crowded that they had to shrink back into the small size that they had originally occupied in the medallons. Kuang-hsu(광저) was a long one, allowing time for the manufacture of numerous robes. Also, it would seem likely that Occidental museums and collections would have a considerable number of his robes, in view of the widespread looting of his palaces during the Allied occupation of Peking in 1900, and the frequent sales of Late Ch'ing imperial textiles by destitute Manchu courtiers in the '20's.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.11
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• pp.1510-1519
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• 2007

This comparative study analyzes and compares tight skirt sewing methods which are found in the clothing configuration reference text books available in contemporary universities and which are used in commercially-available domestic consumer products. The study samples included 15 text books and 12 tight skirt consumer products of different brands on sale at three department stores in Seoul each of which had a belt, a back-centered zipper, and back double slits. The findings of the study are summarized as follows: First, text books mainly show very basic sewing methods of using zippers on both sides of the straight-lined waist belt. This indicates that it is necessary for such methods to be complemented so that they cover a recent variety of designs, materials, and sewing machines. For consumer products, the main sewing method is to use a curved waist belt and a console zipper in silhouette running across half the hipbone. Second, consumer products employ three different types of cutting and sewing methods for putting an inseam on the center of the back slit part: to leave the whole inseam hemmed in the back center, to cut the left side of the inseam to the upper part of the back slit, and to cut the inseam to both the upper parts of the back slit. However, a method shown in most of the sampled text books is to cut the inseam of the back center to both the upper parts of the back slit. Third, the way of finishing a bottom edge hem in the text books is to do slip-stitch, herringbone stitch, and slinting hemming, in order after doing over-lock stitch, or to cut the hem on the bias and then slip-stitch, while for the consumer products the most frequently used sewing method is to finish the bottom edge hem by doing secoui-stitch. Finally, while in the text books the method of stitching darts and tucks is used for lining, the main lining method used in consumer products is to make tucks only. Also in the way of stitching the side seams of lining or the seams of the back center, there is a difference between the two sample groups of text books and the consumer products: while the former suggests using both open seams and over-lock stitch, the latter is found to finish the seams using an over-lock stitch only.

• Clean Technology
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• v.24 no.3
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• pp.183-189
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• 2018

Hollow carbon spheres (HCS) and carbon spheres (CS) were prepared by a hydrothermal reaction and they were introduced as a substrate for the deposition of $MnO_2$ nanoparticles. The $MnO_2$ nanoparticles were deposited on the carbon surface by a chemical redox deposition method. After deposition, the $MnO_2$ nanoparticles were uniformally distributed on the carbon surface in a slit-shape, and sparse $MnO_2$ slits appeared on the HCS surface. The $MnO_2-HCS$ showed an initial specific capacitance of $164.1F\;g^{-1}$ at scan rate of $20mv\;s^{-1}$, and after 1,000 cycles, the specific capacitance was maintained to $141.3F\;g^{-1}$. The capacity retention of $MnO_2-HCS$ and $MnO_2-CS$ were calculated to 86% and 78% in the cycle performance test up to 1,000 cycles, respectively. $MnO_2-HCS$ showed a good cycle stability due to the mesoporous hollow structure which can cause a faster diffusion of the electrolyte and can easily adsorb and desorb $Na^+$ ions on the surface of the electrode.

• Macromolecular Research
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• v.10 no.1
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• pp.2-12
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• 2002

The small-angle X-ray scattering (SAXS) beamline BL4C1 at the 2.5 GeV storage ring of the Pohang Accelerator Laboratory (PAL) has been in its first you of operation since August 2000. During this first stage it could meet the basic requirements of the rapidly growing domestic SAXS user community, which has been carrying out measurements mainly on various polymer systems. The X-ray source is a bending magnet which produces white radiation with a critical energy of 5.5 keV. A synthetic double multilayer monochromator selects quasi-monochromatic radiation with a bandwidth of ca. 1.5%. This relatively low degree of monochromatization is sufficient for most SAXS measurements and allows a considerably higher flux at the sample as compared to monochromators using single crystals. Higher harmonics from the monochromator are rejected by reflection from a flat mirror, and a slit system is installed for collimation. A charge-coupled device (CCD) system, two one-dimensional photodiode arrays (PDA) and imaging plates (IP) are available its detectors. The overall performance of the beamline optics and of the detector systems has been checked using various standard samples. While the CCD and PDA detectors are well-suited for diffraction measurements, they give unsatisfactory data from weakly scattering samples, due to their high intrinsic noise. By using the IP system smooth scattering curves could be obtained in a wide dynamic range. In the second stage, stating from August 2001, the beamline will be upgraded with additional slits, focusing optics and gas-filled proportional detectors.