• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.145-146
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• 2011

A micro-grid (MG) is usually interconnected to the main grid through the dedicated line. Immediately after the removal of the grid supply, the MG should be disconnected and remain disconnected until the main grid is re-energized. It should detect islanding condition as soon as it happens to adjust the setting of the protection relays in the MG. This paper proposes an islanding detection algorithm for the MG based on the active and reactive power delivered to the dedicated line in the time domain. The performance of the proposed algorithm is verified under islanding conditions and fault conditions using the PSCAD/EMTDC simulator. The results indicate that the proposed algorithm can discriminate the islanding conditions from the various fault conditions.

• BMB Reports
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• 제34권2호
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• pp.139-143
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• 2001

Thioredoxin (Trx) is a redox protein possessing conserved sequence Cys-Gly-Pro-Cys in ail organisms. Trx acts as an electron donor of many proteins including thioredoxin peroxidase (TPx). Yeast Trx 2 has two redox active cysteine residues at positions 31 and 34. To investigate the redox activity of each cysteine, we generated mutants C31S, C34S, and C31S/C34S using site directed mutagenesis and examined the redox activity of Trx variants as an electron donor for yeast TPx enzymes. None of the three Cysmutated Trx proteins was active as a redox protein in the 5', 5'-dithiobis-(2-dinitrobenzoic acid) reduction under the condition of the presence of NADPH and thioredoxin reductase, and in the thioredoxin dependent peroxidase activity of yeast TPx II. C34S enhanced the glutamine synthetase protection activity of yeast TPx I, even though 100 times more protein was needed to exhibit the same activity to WT. The formation of a mixed disulfide intermediate between Trx and TPx II subunits was analyzed by SDS-PAGE. The mixed dieter form of TPx II was found only for C34S. These results suggest that Cys-31 more effectively acts as an electron donor for TPx enzymes.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.289-292
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• 2003

디지털화된 멀티미디어 컨텐츠는 고속의 디지털 네트워크를 통해 제작자로부터 소비자에게 직접 전달되는 형태로 변화하고 있으며, 아울러 디지털 컨텐츠를 보호하기 위한 저작권의 보호라는 커다란 문제와 직면하여 이를 보호하고 디지털 컨텐츠를 활성화하기 위한 노력이 한창 진행 중이다. 또한, 보다 효율적인 체계로의 변화를 요구하고 있는 상황에서 디지털 컨텐츠 분야의 비즈니스에 사용 될 기본적인 매개체인 저작권 문서의 효율성이 강조되고 있는 실정이다. 따라서 컨텐츠를 제공하는 특정 시스템에 머무르지 않고 같은 목적을 가진 타 시스템과 컨텐츠를 공유하기 위한 범용적인 비즈니스 모델의 설계가 요구되고 있다. 이에 본 논문에서는 범용 디지털 컨텐츠에 적용 가능한 비즈니스 모델을 설계하였으며 설계된 비즈니스 모델에 따른 저작권 문서 편집 시스템을 설계 및 구현하였다.

• 자동차안전학회지
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• 제7권4호
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• pp.20-25
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• 2015

The basic point of a vehicle recall is to remove vehicle defects as soon as possible and thus prevent possible road traffic accidents caused by the defects beforehand. Therefore, the core of vehicle recall under the self-certification system consists of a timely response and fast remedy of defects. The present study aimed to deduce a plan for improvement of the system necessary for the fast remedy of defects through a phased analysis of defect investigation procedure based on defect investigation statistical data. There will be a need to make the TSB(Technical Service Bulletin) or service campaign data submission of a manufacturer compulsory for the collection of broad defect information in the stage of information analysis and to impose a higher penalty when the manufacturer violates the data submission in the investigation stage. In addition, it is considered that an active service campaign should be induced and a punishment for late recall will be needed for consumer protection.

• Smart Structures and Systems
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• 제17권5호
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• pp.691-708
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• 2016

Recently, number of smart material are investigated and widely used in civil construction and other industries. Present study investigates the application of smart semi-active piezoelectric friction damper (PFD) made with piezoelectric material for the seismic control of the horizontally curved bridge isolated with lead rubber bearing (LRB). The main aim of the study is to investigate the effectiveness of hybrid system and to find out the optimum parameters of PFD for seismic control of the curved bridge. The selected curved bridge is a continuous three-span concrete box girder supported on pier and rigid abutment. The PFD is located between the deck and abutments or piers in chord and radial directions. The bridge is excited with four different earthquake ground motions with all three components (i.e. two horizontal and a vertical) having different characteristics. It is observed that the use of semi-active PFD with LRB is quite effective in controlling the response of the curved bridge as compared with passive system. The incorporation of the smart damper requiring small amount of energy in addition with an isolation system can be used for effective control the curved bridge against the dynamic loading.

• 한국결정성장학회지
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• 제5권4호
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• pp.370-377
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• 1995

우주 항공 기술의 첨단인 Space Shuttle Orbiter(SSO)의 두 coating material 인 Reaction Cured Glass(RCG)와 Spinel(C742)을 제조하여, 표면 위에 부딪히는 원자들의 재결합 가능성 $\gamma$를 확산반응기에서 측정하였다. SSO의 재진입 온도인 약 1000K에서 C742의 산소 원자들의 재결합 가능성 $\gamma$는 $3 {\times} 10^{-2}$으로 RCG에서의 $4 {\times} 10^{-4}$ 보다는 더 큰 값을 갖는다. C742에서 $\gamma$값이 더 높다는 것은 RCG에서 보다 더 많은 활성점을 갖고 있다는 것을 의미한다. 낮은 온도에서 활성점에 있는 원자의 탈착을 유도함으로써 보다 활성이 낮은 표면 코팅 재료를 개발할 수 있다.

• Archives of Pharmacal Research
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• 제28권9호
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• pp.1037-1041
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• 2005

Geranium (Pelargonium inquinans Ait) leaves were extracted with $80\%$ MeOH, and partitioned into n-hexane, ethyl acetate, BuOH and $H_2O$ to isolate the anticoagulant principles. The EtOAc fraction was found to be the most active, and was further purified using silica and octadecylisilane column chromatography employing a bioassay-guided fractionation method. The active compound was isolated and identified as $1,2,3,4,6-pentagalloyl-\beta-D-glucopyranose$(PGG) (compound I). The isolated anticoagulant significantly prolonged the activated partial thrombin time (APTT) and thrombin time (TT) using normal human plasma. One microgram of $1,2,3,4,6-pentagalloyl-\beta-D-glucopyranose$ showed 0.063 heparin units in the APTT and 2.73 heparin units in the TT for anti-thrombosis. This is the first report of the isolation of PGG from geranium plants.

• The Plant Pathology Journal
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• 제23권3호
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• pp.180-186
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• 2007

The biocontrol agent, Serratia plymuthica A21-4, has been developed for controlling pepper Phytophthora blight. Serratia plymuthica A21-4 strongly inhibits the mycelial growth, zoospore formation, and cyst germination of Phytophthora capsici in vitro. The application of a cell suspension of strain A21-4 to pepper plants in pot experiments and in greenhouse successfully controlled the disease. The bacteria produced a potent antifungal substance which was a key factor in the suppression of Phytophthora capsici. The most active chemical com-pound was isolated and purified by antifungal activity-guided fractionation. The chemical structure was identified as a chlorinated macrolide $(C_{23}H_{31}O_8Cl)$ by spectroscopic (UV, IR, MS, and NMR) data, and was named macrocyclic lactone A21-4. The active compound significantly inhibited the formation of zoosporangia and zoospore and germination of cyst of P. capsici at concentrations lower than $0.0625{\mu}g/ml$. The effective concentrations of the macrocyclic lactone A21-4 for $ED_{50}$ of mycelial growth inhibition were $0.25{\mu}g/ml,\;0.25{\mu}g/ml,\;0.30{\mu}g/ml \;and\;0.75{\mu}g/ml$ against P. capsici, Pythium ultimum, Sclerotinia sclerotiorum and Botrytis cinerea, respectively.

• Asian Pacific Journal of Cancer Prevention
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• 제13권3호
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• pp.897-900
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• 2012

Cervical cancer resulting from prior infection with human papillomavirus (HPV) is a significant public health threat against young Japanese women. A national immunization plan to vaccinate 13~16 year old female students against HPV infection has been started in Japan since 2010, and may reach almost full coverage by the end of 2012. Older age females who may already be sexually active are not targeted by this plan but should follow safer sex practices as well as periodic screening of the cervix cytology to reduce their risk of developing cervical cancer. HPV vaccination alone does not offer full protection either, because only some HPV types are covered by the vaccines and the long-term efficacy of the vaccines has not been determined yet. Therefore, we did a survey at an international university in Japan to study the knowledge and attitude of female college students towards prevention of cervical cancer, to examine the age when they start sexual activity and other related attributes that may influence the risk of cervical cancer. We discuss the results of our survey and what they imply for the possible impact of an HPV immunization plan on the risk of cervical cancer in Japan, and conclude by an emphasis on the need to increase awareness among Japanese female adolescents and to enhance the cervical screening rates among older females who are already sexually active.

• BMB Reports
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• 제29권4호
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• pp.321-326
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• 1996

Spinach glycolate oxidase was subjected to a series of chemical modifications aimed at identifying amino acid residues essential for catalytic activity. The oxidase was reversibly inactivated by treatment with pyridoxal 5'-phosphate (PLP). The inactivation by PLP was accompanied by the appearance of an absorption peak of around 430 nm, which was shifted to 325 nm upon reduction with $NaBH_4$. After reduction, the PLP-treated oxidase showed a fluorescence spectrum with a maximum of around 395 nm by exciting at 325 nm. The substrate-competitive inhibitors oxalate and oxaloacetate provided protection against inactivation of the oxidase by PLP. These results suggest that PLP inactivates the enzyme by fonning a Schiff base with lysyl residue(s) at an active site of the oxidase. The enzyme was also inactivated by tryptophan-specific reagent N-bromosuccinimide (NBS). However, competitive inhibitors oxalate and oxaloacetate could not protect the oxidase significantly against inactivation of the enzyme by NBS. The results implicate that the inactivation of the oxidase by NBS is not directly related to modification of the tryptophanyl residue at an active site of the enzyme. Treatments of the oxidase with cysteine-specific reagents iodoacetate, silver nitrate, and 5,5'-dithiobis-2-nitrobenzoic acid did not affect significantly the activity of the enzyme.