• 한국염색가공학회지
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• 제3권2호
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• pp.25-33
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• 1991

Poly(ethylene terephthalate)(PET) and nylon 6 films stretched uniaxially and biaxially were sputter etched in the presence of argon gas. The surface of the etched films was investigated using a scanning electron microscope(SEM). While cracks perpendicular to the stretched direction were observed in the uniaxil stretched films sputter etched for 30 min., many protrusions were formed in the biaxial stretched films at the height of 0.3-0.4 gm for PET and $0.1-0.2\mum$ for nylon 6. The tops of two or three protrusions merged etching time increased to 60 min. The contact angle to water of the sputter etched PET and nylon 6 films decreased steeply when etched for one to 3 min. In order to investigate chemical changes on the surface ESCA analysis was carried out. In both films sputter etched $C_{1s}$ intensity decreased and $O_{1s}$ intensity increased compared with the unetched ones.

• 한국농공학회지
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• 제39권6호
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• pp.99-110
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• 1997

The study was conducted in order to investigate the basic geotechnical properties of sand-bentonite mixtures with the various bentonite contents. The results obtained are as follows : 1. Optimum moisture content of sand-bentonite mixtures was approximately 17.10~18.52% corresponding to the maximum dry density of 1.58~1 .64gf/$cm^3$. As the bentonite contents and curing peroid increased, both the maximum dry density and optimum moisture content of sand-bentonite mixtures increased. 2. The unconfined compressive strength of sand-bentonite mixtures increased as the increase of bentonite content, but it did not change along the curing period. 3. The sand-bentonite mixtures ruptured at 8~15% of the axial strain and the maxi-mum shearing stress was about O.7Okgf/$cm^2$. 4. According to the increase of bentonite content, the cohesion intercept and internal friction of the sand-bentonite mixtures increased slightly in the shear test, while the cohesion intercept increased largely, and the internal friction angle decreased largely in the triaxial test. 5. Both the initial void ratio and swelling of the sand-bentonite mixtures were very low with respect to the consolidation pressure increase. 6. The swelling and shrinkage of sand-bentonite mixtures increased slightly according to the increment of bentonite content.

• 식품기술
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• 제1권1호
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• pp.26-31
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• 1988

The storage stabilities of philipines; bananas were investigated according to the storage pretreatments and packaging methods during 60 days storage at $13^{\circ}C$. The better storage stability was got in bananas packaged with $60\mum$ low density polyethlene(PE) film inside the carton box than those without inside pack. Radiation gave the adverse effects on effects on bananas was only 20 days. And Shelf-life of bananas in no inner pack was 20 days. Soluble solid content of bananas packaged with PE film was 17 Brix degree after 60 days storage, but that with no inner package was around 20 after 20 days. Color was below 3 in color chart after 60 days storage and hardness was rapidly decreased from 40 days in bananas packaged with PE film, but color was became to 3 color after 30 days and hardness was rapidly decreased after 20 days in bananas without inner package. rarcentage of deteriorated bananas were below 3% in PE films after 60 days strorage, but 100% after 40 days in bananas without inner package.

• Journal of Advanced Marine Engineering and Technology
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• 제21권4호
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• pp.387-392
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• 1997

This paper describes a combination surge generator for carrying out performance tests on the surge protection circuits of shipboard electrical systems. Pspice simulations were performed to decide the values of the parts required and to analyze the characteristics of the generator circuitry. The surge generator fabricated can produce four of the most common surge test waveforms : the O.5i/S/100kHz Ringwave, the 1.2/50$\mu$S voltage, the 8/20$\mu$S current, and the lO/lOOOi/S voltage wave¬forms specified in ANSI Std. C62. Source impedances of the surge generator are 12$\Omega$ in the O.5$\mu$S/100kHz mode, O.5$\Omega$ in the 1.2/50$\mu$S and 8/20$\mu$S mode, and 40$\Omega$in the l0/1000$\mu$S mode, and are determined by the ratio of the maxi¬mum open - circuit voltage to the maximum short - circuit current. Experimental results show that the surge generator provides most of the outputs required for the testing of the surge protection circuits on shipboard electrical systems.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권11호
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• pp.555-561
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• 2001

In this paper, the low power (1.5 W) solenoid-type magnetic thin-film transformers utilizing a $Ni_{81}Fe_{19)$ core material were designed and fabricated for 5 MHz-drive DC-DC converter application. The $20\mum$ thick copper films were used as the coils. The transformers fabricated in this work have the sizes of $3.08 mm\times25.5 mm\; and\; 6.15 mm\times12.75 mm.$ The optimum design of solenoid-type magnetic thin film transformers was performed utilizing the conventional equations, a Maxwell computer simulator (Ansoft HFSS V7.0 for PC), and parameters obtained from the magnetic properties of NiFe magnetic core materials. frequency characteristics of inductance, dc resistance (R), coupling factor (k) and gain of developed transformers were measured using HP4194A impedance and gain-phase analyzer. The fabricated transformers with the size of $6.15 mm\time12.75 mm$ exhibit the inductance of $0.83 \muH$, the dc resistance of $2.3\Omega$$\Omega$, the k of 0.91 and the gain of -1 dB at 5 MHz, which show the comparable results to those reported in the recent literatures. The measured high-frequency characteristics for the fabricated transformers agreed well with those obtained by theoretical calculations .

• 보존과학연구
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• 통권19호
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• pp.109-132
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• 1998

According to excavation of Imdang site, these sites were excavated place to a various of sites from Early lron period to the Koryo Kingdom. Artifacts to be conserved were excavated from A, D and E district. Metal artifacts were excavated from D and E district and lacquer ware artifacts were excavated from Adistrict. Metal artifacts including lacquer ware iron sword, imitative bronze mirror, Osujen and bronze artifact with letter and so on. Bronze artifacts were covered with soil and rust and performed consolidation after passivation treatment with Benzotriazole solution. Also, iron artifacts performed desalting treatment with 0.1M sesquicarbonate solution. After desalinization, adhesive of these artifacts were processed with Araldite(rapid type) after consolidation with20%∼30% NAD-10 solution. Lacquer ware artifacts remained fragments of lacquer to be all corroded and soiled. Therefore these artifacts retained its original form. Fragments of lacquer joined with Caparol 1%∼3% solution and the soil of relics coated with PSNY 3%∼6% solution. There were many kinds of lacquer were. Lacquer ware artifacts presumed to a string instrument that provide important clues for lacquer ware research. As for lacquer fragments inquire, paints grain size were $2∼5\mum$ and conformed to vanished three times.

• 수완나부미
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• 제2권1호
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• pp.1-16
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• 2010

Vietnamese Blue and White Porcelain is famous for its unique form and colour of cobalt. It is said to be producted from the late of 14th Century to now. Vietnamese Blue and White Porcelain of 14th Century has a Mum design similar to that of Blue and White Porcelain of 14th Century in China. The Vietnamese Blue and White Porcelain of 15th, 16th Century was trade Ceramics which were shipped overseas. A base, having a dated inscription corresponding to 1450 and kept in the Topkapi Saray Museum is the best example of Vietnamese trade ceramics. The Vietnamese Blue and White Porcelain of 15th, 16th Century was a substitute for Chinese trade ceramics in these times when China had a police of the closure of China borderers to sea trade to protect China and was exported to the western Asia and the Southeast Asia. In recent, Fustat relics of Egypt was excavated the Vietnamese Blue and White Porcelain. It means that Vietnamese Ceramics of 15th, 16th Century was substitute for Chinese trade ceramics. In addition, Thai Blue celadon of 15th Century was exported to the western Asia as like Vietnamese Blue and White Porcelain. But when a police of the closure of China borderers to sea trade in China was stopped in the late of 16th Century and Chinese Ceramics were reborn in the same time, the Vietnamese Blue and White Porcelain was declined as trade items.

• 한국염색가공학회지
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• 제35권3호
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• pp.137-150
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• 2023

This paper investigated the applicability of polyester yarn coating using ther- moplastic polyester elastomer (TPEE) to replace polyvinyl chloride (PVC) coated yarn for blinds fabric. For this purpose, suitable TPEE for yarn coating was selected by measuring thermal and rheological properties and the yarn coating process conditions were investigated by changing variables such as extrusion temperature, die and nipple dimensions, take-up speed, and core yarn denier. TPEE coated yarns with a diameter of 0.3 and 0.4 mm were prepared, respectively. Tensile properties and cross-section uniformity revealed by a scanning electron microscopy (SEM) of the TPEE coated yarn were analyzed. Among several candidates, TPEE having a melt index of 35 and melting temperature of 153℃ was the most suitable for replacing PVC, and the opti- mum coating conditions for the TPEE coating yarn were a head temperature of 170℃ and core yarn denier of 420 denier. The selected TPEE coated yarns have enough ten- sile strength and uniformity to replace present PVC coated yarns, certified by SEM photograph.

• 한국동물학회지
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• 제26권4호
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• pp.253-270
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• 1983

흰쥐를 실험 동물로 하여 각간핵의 신경세포의 미세구조와 신경연접 기구를 확인하고, 고삐핵으로 부터 각간핵으로 투사되는 축삭종말의 형태를 밝히기 위하여 고삐핵을 전기적으로 제거(electrolytic lesion)한 후 간각핵에서 퇴행성 변화를 보이는 축삭종말을 전자현미경으로 관찰하였던 바, 다음과 같은 결론을 얻었다. 1. 흰쥐 각간핵에는 크기에 따라 대신경세포 ($27\\times12 \\mum$)와 소신경세포 ($15\\times10 \\mum$)가 구별되었다. 대신경세포는 그 세포질내에 잘 발달된 소기관들이 있었으며, 핵에는 약간의 핵막 함입이 형성되어 있었다. 소신경세포는 소기관들이 빈약하게 발달되어 있었고 핵은 매우 깊은 핵막의 함입이 이루어져 있었다. 이들 대, 소신경세포의 구성비는 3:7 정도로 소형세포가 많았다. 2. 각간핵의 신경종말의 현접형태는 그 종말내에 포함되어 있는 연접소포의 크기와 모양 및 분포 상태, 그리고 연접부에 형성된 연접치밀질의 발달에 기초를 두어 관찰한 결과 4형이 구별되었다. 제I형 연접은 작고 둥근 연접소포 (직경 40 nm)를 포함하여, 비대칭성 연접을 이루었고, 본연접이 가장 많이 출현하였다(40%). 제II형 연접은 크고 원형의 연접소포(직경 45 nm)를 포함하며, 대칭성인 연접치밀질을 형성하였고, 그 출현율은 18%였다. 제III형 연접은 원형 및 난원형 (직경, $25\\times40 nm$)이 섞여 있었으며, 대칭성인 연접을 형성하고 있었고, 33%의 출현율을 보였다. 제IV형 연접은 타원형의 연접소포 (직경, 25\\times50 nm$)를 갖고 있었으며 대칭성인 연접을 띠고 있었다.

• 한국응용곤충학회지
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• 제28권1호
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• pp.32-36
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• 1989

Cypermethrin과 pirimicarb도태 저항성계통 복수아흑진딧물(Myzus persicae Sulzer)에 대한 acephate, cypermethrin, demeton-S-methyl, pirimicarb 상호 혼합시의 연합독작용을 검토한 결과는 다음과 같다. Cypermethrin 도태 저항성계통에 Cypermethrin+acephate, cypermethrin+demeton-S-methyl, cypermethrin_pirimicarb를 처리하였을 때, 혼합비에 따른 정도의 차이는 있었으나. 독립작용 또는 길항작용을 보였다. Pirimicarb 도태 저항성계통에 pirimicarb+acephate, pirimicarb+cypermethrin을 각각 8:2, 2:8 혼합처리하였을 때 최대의 협동결과를 보였으나, pirimicarb+demeton-S-methyl의 경웨는 혼합비에 관계없이 길항작용을 나타내었다.