• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.10
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• pp.1451-1457
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• 2002

When an aqueous liquid such as water having high electric conductivity and high surface tension is discharged from a nozzle under a strong DC electric field, fine drops ranging from 30 to 450 microns can be obtained only through the spindle mode. In the present study, effects of the electric conductivity and the surface wettability of nozzle materials on formation of drops with this mode were investigated. For that, three nozzles with the same size but with different materials were prepared and tested; a stainless steel needle, and a plain and a metal (gold)-coated (except for the tip portion) silica needles. Uniform drops were obtained with the gold-coated silica nozzle over the wider range of the DC voltage input. That is, formation of the liquid cone and detachment of the liquid spindle (ligament) can be more stabilized and frequent with the needles having high electric conductivity but with low surface wettability at their tips.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.3
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• pp.19-27
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• 2011

A weaving machine for texture industry uses a lot of needles and the nib of these needles is necessary to be kept with sharp edge. The re-grinding of the needle by a special purpose of the grinding wheel can be selected for achieving this aim. This study focused on the manufacture and performance assessment the special grinding wheel. A forming mold for the grinding wheel was designed and a sintering process for furnace process control was established. Manufactured wheels were tested for determining suitable grade of the wheel. The selection of optimal grinding conditions was achieved by a response surface method and a genetic algorithm.

• Journal of Korean Society for Atmospheric Environment
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• v.1 no.1
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• pp.25-32
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• 1985

To examine the effects of air pollution on Pinus thunbergii growing around Yocheon Industrial Complex, evaluation of visible injury based on Injury Index and chemical analysis of water-soluble sulfur and fluorine contents in needles were carried out on 30 sampling sites. Histological responses of needles were also investigated on the necrotic needle tissues. Not only Injury Index but water-soluble sulfur and fluorine contents were higher at all sites than those at control site, and showed significant correlationship among them. Especially, they were rather higher in the vicinity of air pollutants sources. Water-soluble sulfur contents were positively correlated with average atomospheric $SO_3$ concentrations. Microscopic examination of necrotic needle tissues showed that mesophyll cells were collapsed with hypertrophy and collapse of transfusion cells.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.439-457
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• 2000

The causes, risk factors and sequelae of mastectomy were studied, and the physical therapy approaches on post-mastectomy was discussed in this study. It was found that the patients taken mastectomy have experienced pins and needles in muscle, weakening of muscle, pains, deterioration of motion in joint region and activities of daily living, psychiatric sequelae, and etc even after the conservertive therapies like the chemical therapy, radiotherapy, immunotherapy, and hormone therapy. However, few study on the physical therapy approaches for patients with breast cancer has been carried in Korea at present. The followings were proposed as the physical therapy approaches. 1. Shoulder joint motion approach to relax the limit of range of motion 2. Control of breathing exercise for dealing with removal of the pectorailis muscle 3. Method to reduce the edema of arms for tackling the cut of lymph node 4. Method to reduce pains, pins and needles 5. Support home exercise program after discharging from hospital, sexual life and pregnancy, and activities of daily living training method.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.227-232
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• 2000

Fresh pine needles were collected and extracted with 95% methanol and the extract was concentrated to determine its antimicrobial activity. The methanol extract had a considerable inhibitory effect on the tested bacteria, such as Esherichia coli 0157;H7, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. The methanol extract of pine needles was further fractionated to chloroform, ethylacetate, butanal, and water fractions. Among these four fractions, the butanol and water fractions, which showed a relatively strong inhibitory effect on all of the tested bacteria, were purified and the minimum ingibitory concentration (MIC) was determined for each microorganism. The MIC raged between 25 mg/ml and 45 mg/ml depending on the microorganism. the purified active fractions were applied to sterilized milk as a model food system to define the antimicrobial effectiveness and it was found that the antimicrobial activities in the water fractions were stronger than those in the butanol fractions.

• Journal of the Korean Wood Science and Technology
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• v.16 no.2
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• pp.62-68
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• 1988

잣나무의 Diterpene resin acids의 함량을 조사하기 위하여 침엽(needle), 일차조직(cortex), 목질부(sylem)별로 수지를 채취하여 최근 유행하고 있는 capillary column을 사용하는 GC를 이용하여 정량분석을 하였다. 분석결과 7종의 resin acid가 밝혀졌으며, 그 중 lambertianic acid는 neelde에서 74~87%, cortex에서 42-57%, xylem에서 18-28%로 분석되었는데, 다른 Pinus류에서 보다 훨씬 많은 양이 함유되어 병리곤충 분야나 농약 분야에서 고찰할 만한 가치가 있다고 생각하며, 그 외 l-obrnyltrans-p-coumarate, isocupressic acid pinusolide 등도 분석 되었다.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1423-1428
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• 2003

We investigated the amount of the toxic gases emitted from the Electrostatic Precipitators(ESPs), which were currently used by indoor air cleaners. We used the wire-to-plate(WTP) type and the needle-to-plate(NTP) type corona discharger in our study. Using the voltage, the polarity of wire, the number of needles of NTP as the input variables, we studied the characteristic of Ozone and $NO_x$ generation in the ESPs. As the results, we found out that the concentration of Ozone, $NO_2$ and $NO_x$ is increased, but the amount of NO is decreased with increasing the voltage and the number of needles. And we knew that the generation rate of ozone and $NO_x$ is very related with the corona region.

• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.45-51
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• 1997

주목 잎을 채취하여 건조하고 아세톤-물 (7 : 3, v/v) 의 혼합액으로 추출한 후 에틸아세테이트 및 수용성 부분으로 분리하고 Sephadex-LH 20으로 충진한 칼럼을 이용하여 2개의 flavan 단량체와 2개의 후라보노이드 배당체를 단리하였다. 에틸아세테이트용성 추출물은 대부분 (+)-catechin 과 (-)-epicatechin으로 구성되어 있었으며 수용성 부분에서는 quercetin-3-0-arabinopyranosyl-($1"'{\rightarrow}6"$)-${\beta}$-D-glucoside와 quercetin-3-O-rutinoside 인 두 개의 탄수화물로 구성된 배당체를 분리하였으며 주목에서는 이들 화합물은 아직 보고된 바가 없다. 이들의 구조결정을 위하여 박층크로마토그래피를 실시하고 $^1H$-NMR과 $^{13}C$-NMR 스펙트럼을 기존의 스펙트럼과 비교, 분석하여 정확한 구조를 규명하였다.

• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.81-87
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• 1997

일본잎갈나무잎을 채취하여 아세톤 : 물 (7 : 3, v/v) 의 혼합용액으로 추출한 후 에틸아세테이트용성 화합물과 수용성 화합물로 분리하였으며 Sephadex LH-20으로 충진한 칼럼을 사용하여 화합물을 단리 하였다. 단리 화합물을 확인하기 위하여 셀룰로오스 박층 크로마토그래피(TLC)를 실시한 후 자외선 램프 하에서 관찰하였다. 바닐린 발색제를 분무히여 정색반응을 조사하고 $R_r$ 값을 구하였다. 단리된 화합물들의 구조는 $^1H$-NMR과 $^{13}C$-NMR 스펙트럼을 이용하여 그 구조를 규명하였으며 에틸아세테이트용성 화합물에서는 (+)-catechin, (-)-epicatechin, kaempferol-O-arabinofuranoside와 kaempferol-3-O-arabinopyranoside, 수용성 화합물에서는 apigenin-8-C-rhamnosyl-($1"'{\rightarrow}2"$)-glucoside(2"-O-rhamnosylvitexin)을 단리 하였다.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.155-157
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• 1997

This paper presents the results of an experimental investigation of ground impedance in the low frequency region regarding the transiant state on the soil and ground electrodes(rod, electric rod with needles, electric mesh). The grounding resistance playing an important part in substation grounding designs is measured. Especially, the reduction effect of ground impedance by using the electric rod with needles in the soils are presented.