• Journal of Ginseng Research
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• 제20권3호
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• pp.331-338
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• 1996

This study was conducted to screen the antagonistic plants on northern root-knot nematode (Meloidogyne) and to utilize those in its control. Egg hatching of M. hapla was found to be inhibited by 17 plant methanol extracts, and 11 plant extracts among them were also toxic to M. hapla second stage juvenile. Egg hatching of iW. hapla was also found to be inhibited by squeezed extracts of Cassia tora and Zea mays, and they were also toxic to M. hapla second stage juvenile. Extracts of Achyranthes japonica, Melia axedrach and Acorus graminens were toxic to M. hapla second stage with a juvenile mortality above 70clc at the 10 folds diluted concent ration and A. graminens was toxic to tested juvenile mortality above 50% at the 100 folds diluted concentration. The toxicity was directly propotional to the diluted concentration of the plant extracts and to the exposure period. Punica granatum, Acorns graminens and Melia axedrach were effective in inhibiting root penetration of JW. hapla juveniles, among of them p. granatum is most effective Percent inhibition of penetration by second and third stage juveniles into tomato slants penetrating by it was 72.7 and 82.4%, respectively.

• 한국미생물·생명공학회지
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• 제22권3호
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• pp.290-295
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• 1994

Micelle, liposome and polyethylene glycol(PEG) were employed to reduce the cell mem- brane toxicity of Amphotericin B(Amp. B). Cholesterol-sulfate which can form a mixed micelle with Amp. B molecules was found very effective for the reduction of Amp. B toxicity. 0.01% of cholesterol-sulfate could reduce the toxicity of 5X 10$^{-6}$ M Amp. B by 90%. The required concent- ration of cholesterol-sulfate for the toxicity reduction was proportionally increased with increasing Amp. B concentration. PEG was also effective on the reduction of Amp. B toxicity. 2% PEG was required for the reduction of toxicity by 50%, regardless of Amp. B concentration. The liposome system showed an effective reduction of Amp. B toxicity on RBC, maintaining the antibiotic effect on Candida albicans as free drugs. This seems to be due to the fact that liposome bilayer plays a role of buffer system between ergosterol of fungi cell membrane and cholesterol of red blood cell membrane, which leads the redistribution of Amp. B between them, as the result, the reduction of drug toxicity on cell membrane.

• 한국정밀공학회지
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• 제1권3호
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• pp.71-84
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• 1984

This paper examined strain distribution and radius of curvature of the bulge by finite element method and investigated limit polar thickness strain to predict the formability of sheet metal as we substituted effective strain and the radius of curvature obtained by FEM into instability condition equation successively. In experiment, the radius of curvature and limit polar thickness strainwere obtained by Moire method. Also, a concent- ric set of photogrid circles was used to measure the strain of arbitrary point and mild steel was used as material. This results obtained are as follows: 1) The radius of curvature obtained by FEM is in good agreement with the Moire experimental value. 2) The polar thickness strain is getting larger as the inside is approached from the edge. This means that fracture occurred near the ploe. 3) The circumferential strains agree closely with the meridian strains and the polar thickness strain is about twice the circumferential (or meridian) strain. This result agrees with the fact that anisotropy coefficient (R-value) obtained by tensile test is about one. 4) The theoretical results of limit polar thickness strain obtained by authors' method are better agreement with experimental results than other theoretical results. Therefore, we can better predict the formability of sheet metal with authors' method.

• 한국전자통신학회논문지
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• 제16권6호
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• pp.1113-1120
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• 2021

콘텐츠 중심 네트워크(CCN)은 기존 위치(IP) 기반의 네트워크 방식을 콘텐츠 이름(Content Name) 중심의 네트워크 구조로 변모시킴으로써 네트워크 전반의 효율성을 높이고자 하는 시도이다. CCN에서는 네트워크 효율을 높이기 위해 라우터 저장공간을 활용한 캐싱을 수행하는데, 캐시 교체정책은 CCN의 전반적인 성능을 좌우하는 중요한 요소이다. 따라서 CCN 분야에서는 캐시 교체정책과 관련된 많은 선행 연구가 있었다. 본 논문에서는 CCN 기본 캐시 교체정책인 LFU를 개선한 실시간 생성자 인기도 기반의 캐시 교체정책을 제안하였다. 또한, 실험을 통해 제안한 캐시 교체정책이 대조군보다 우수함을 입증하였다.

• 융합신호처리학회논문지
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• 제16권3호
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• pp.115-121
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• 2015

가정 및 사무실의 전기/전자 기기가 내부 혹은 외부로부터 주 기능 수행을 위한 명령을 기다리고 있는 상태에서 소모되는 대기전력을 차단할 수 있는 장치를 저가로 개발하였다. 대기전력을 줄이기 위한 노력이 선진국들뿐만 아니라 국제적 차원에서 경주되고 있다. 우리나라도 가구당 전자/전기기기 보유대수가 증가되는 추세에 따른 대기전력이 점차 증가하고 있어 전기 에너지 낭비의 큰 요인이 되고 있다. 기존의 대기전력 차단장치는 그 장치 자체의 소비전력이 크고, 구조가 복잡하여 사용 의미를 퇴색시키는 문제점을 안고 있다. 본 논문에서는 기존 제품의 이러한 문제점을 보완시키고 대기전력을 완전히 차단하는 저가형 대기전력 차단장치를 제안한다. 그리고 제안한 대기전력 차단장치를 누전차단기와 콘센트에 적용하여 회로를 설계 및 구현하고 실험을 통하여 그 우수성을 확인하였다.

• 대한간호학회지
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• 제30권5호
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• pp.1219-1229
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• 2000

The purpose of this study was to describe and understand how diabetics dealt with the result of the various changes of lifestyle. The grounded theory approach of qualitative research methods was used for building a substantive theory about that. The subjects of this study were 10 clients who experienced diabetes from 4 to 30 years. The data was collected from August 1999 to November 1999 through in-depth interviews utilizing home visitation and telephone interview technique then it was and analyzed simultaneously by a constant comparative method in which the new data was continuously coded into categories and properties according to Strauss & Corbin,s methodology. One hundred six concepts were found and they were grouped into 35 categories and then into 14 categories. The results were as follows difficulty, unable to overcome the changes, disposition, disease process, tiredness, supportive environment, perception, handling, concent- ration, mastering, endurance, avoidance, giving up and tailoring. The core phenomenon was 'tiredness' and these categories were synthesized into one core concept, the process of tailoring. The process of tailoring in diabetics consisted of : 1) going through difficulty of disease management 2) experiencing tiredness from the difficulty of disease management 3) perception of disease from tiredness 4) undergoing various self-management 5) controlling the process of tailoring by one's own method. Six hypotheses were derived from the relation of these concepts and four types were from intensity of tiredness, direction of disposition, type of disease process and the level of supportive environment and perception. This study offers better understanding on diabetic experiences and may facilitate more appropriate interventive strategies to provide support, information and knowledge. The nurses should utilize the results to help diabetics enjoy their lives without any trouble and must continuously develop nursing knowledges and skills.

• 한국환경과학회지
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• 제6권2호
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• pp.141-152
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• 1997

The pilot plant had been made so as to be an association system from the various items managed to have degrees of efficiency and It have been done to consider the experimental result with irradiance period and pH influence of all major things to treatment function of Waste Stabilization Pond. The results are as following. The attained results for continuous & cyclic irradiance 1. 24L.-reactor was prior to 12L.-12D.-reactor on oxygen generation & algal production ability. 2. 24L.-reactor was prior to 12L.-12D.-reactor on nutrients removal efficiency. 3. In 24L.-reactor it maintained 5mg/L∼6mg/L, DO concent enough to a fish's survival. The attained results for pH condition 1. Oxygen generation ^ algal production in pH 4-reactor were higher than those in pH 10-reactor. 2. The acidic condition at pH 4 and alkalic condition at pH 10 did not so much affect an algal growth and nutrients removal. The attained results for whole 1. In view of the results appeared as [(NH3-N)+(NO3-N)] removal efficiency, 89.1%∼93.9% and PO4-P removal efficiency, 34.3%∼83.7% & COD removal efficiency, 88.5%∼93.9%. It is possible to treat the wastewater with starch and pH which have been known as thedifficult problem. 2. At the point of non using methanol to nitrificate NO3-N, the nutrients removal method by using an algal growth is the most economical method in the whole nutrients removal methods. 3. The nutrients removal method by using an algal growth contributes to natural ecosystem. 4. The nutrients removal method by using an algal growth is excellant in the prevention against the eutrophication.

• 한국환경농학회지
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• 제33권4호
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• pp.306-313
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• 2014

BACKGROUND: Forest soils contain microbes capable of consuming atmospheric methane ($CH_4$), an amount matching the annual increase in $CH_4$ concentration in the atmosphere. However, the effect of plant residue production by different forest structure on $CH_4$ oxidation is not studied in Korea. The objective of this study was to evaluate the effect of Korean alpine soils having different forestation structure on $CH_4$ uptake rates. METHODS AND RESULTS: the $CH_4$ flux was measured at three sites dominated with pine, chestnut and oak trees in southern Korea. The $CH_4$ uptake potentials were evaluated by a closed chamber method for a year. The $CH_4$ uptake rate was the highest in the pine tree soil ($1.05mg/m^2/day$) and then followed by oak ($0.930mg/m^2/day$) and chestnut trees ($0.497mg/m^2/day$). The $CH_4$ uptake rates were highly correlated to soil organic matter and moisture contents, and total microbial and methanotrophs activities. Different with the general concent, there was no any correlation between $CH_4$ oxidation rates, and soil temperature and labile carbon concentrations, irrespective with tree species. CONCLUSION: Conclusively, the methane oxidation rate was correlated in positive manner with organic matter, abundance of methanotrophs. Methane oxidation was different among tree species. This results could be used to estimate methane oxidation rate in forest of Korea after complementing information about statistical data and methane oxidation of other site.

• The Korean Journal of Ecology
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• 제15권4호
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• pp.433-449
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• 1992

Three horticultural herbaceous plants and a natural herbaceous plant were tested to determine the growth responses, biomass and uptake of cadmium(cd), lead(pb) by application of cd and pb soil treatment in pot culture. The ecological effects on the growth of the plants were investigated to determine the tolerance for the heavy metal pollutants cd and pb. the marginal concentrain of cd treatment on the growth of the each plant was below the 1, 000 ppm treatment of cd. The marginal concentration of pb treatment was below the 1, 000ppm treatment of pb in cultivation of salvia splendens ker., celosia cristata l. and below the 3, 000ppm treatment of pb in cultivation of portulaca grandiflora hook., sedum saramentosum bunge. the resistance for cd of sedum saramentosum bunge, celosia criastata l., portulaca grandiflora hook. and salvia splendens ker. was in the listed order. The resistence for pb was in order of sedum saramentosum bunge, portulaca grandiflora hook. Salvia splendens ker.and celosia criastata l.stems. The flowering of portulaca grandiflora hook. was sustained in the pb 1, 000ppm treated group only. The higher the concentration of pb in the soil cultivated the plants was, the less the content of leaf chlorophy11 in each plant was. The number of stomata per unit leaf area was the highest in salvia splendens ker. and in order of celosia l., sedum saramentosum bunge., portulaca grandiflora hook., the higher the cd and pb concentration of cd and pb treatment was, the more the concent of cd and pb in the part of each plant increased. the content of cd and pb in the stems of salvia spiendens ker. was the highest in the 1, 000ppm-treated ground and in order of the roots, the leaves and the flowers.

• Progress in Superconductivity
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• 제13권2호
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• pp.127-132
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• 2011

Many research groups have been manufacturing coated conductor by various processes such as PLD, MOD, and MOCVD, but the methods with production cost suitable for wide and massive application of coated conductor did not develop yet. Spray pyrolysis method adopting ultrasonic atomization was tried as one of the possible option. GdBCO precursor films have been deposited on IBAD substrate by spray pyrolysis method at low temperature and converted to GdBCO by post heat treatment. Ultrasonic atomization was used to generate fine droplets from precursor solution of Gd, Ba, and Cu nitrate dissolved in water. Primary GdBCO films were deposited at $500^{\circ}C$ and oxygen partial pressure of 1 torr. After that, the films were converted at various temperatures and low oxygen partial pressures. C-Axis oriented films were obtained IBAD substrates at conversion temperature of around $870^{\circ}C$ and oxygen partial pressures of 500 mtorr ~ 1 torr in a vacuum. Thick c-axis epitaxial film with the thickness of 0.4 ~ 0.5 ${\mu}m$ was obtained on IBAD substrate. C-axis epitaxial GdBCO films were successfully prepared by ex-situ methods using nitrate precursors on IBAD metal substrate. Converted GdBCO films have very dense microstructures with good grain connectivity. EDS composition analysis of the film showed a number of Cu-rich phase in surface. The precursor solution having high copper concent with the composition of Gd : Ba : Cu = 1 : 2 : 4 showed the better grain connectivity and electrical conductivity.