• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.344-351
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• 1999

The safe operation of electro railways is greatly dependant on its protective systems. The system so-called Fault Protection Wire(FW) is now widely adapted to protect in AT feeding systems. It is connected between the feeder and trolley circuit to return the fault current to autotransfonmers at substation. This paper computed the distribution of fault currents at FW in the system and also evaluated the safety from electric shock when ground fault or flashover occur in the feeding system. The results show FW is useful to protect power supply network from fault in electric railways

• 동의생리병리학회지
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• 제26권2호
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• pp.181-188
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• 2012

The object of this study was to observe the gatro protective effects of BJS-mix001, a mixed herbal formula consisted of 4 herbal drugs Pinelliae Rhizoma : Coptidis Rhizoma : Massa Medicata Fermentata : Ostreae Testa = 1 : 1 : 1 : 1 (g/g) mixtures, which were main component of oriental medicine for treating various digestive diseases, in indomethacin induced gastric damages in rats. Three different dosages of BJS-mix001 (200, 100 and 50 mg/kg) were once orally administered 30 min before indomethacin treatment. Six hrs after indomethacin treatment, changes on the gross lesion scores, fundic histopathology, MPO activity and anti oxidant activities were observed. The results were compared with omeprazole, antioxidant and proton pump inhibitor 10 mg/kg and DA-9601, a standardized extract of the herb Artemisia asiatica 100 mg/kg treated group, respectively. As results of all three different dosages of BJS-mix001 in the indomethacin induced gastric damaged rats, significant decreased gastric damages were detected as compared with the indomethacin treated control rats. BJS-mix001 also strengthened the antioxidative defense systems - decreased the level of lipid peroxidation and catalase activity but increased the level of superoxide dismutase and glutathione contents. BJS-mix001 showed similar gastro protective effects as compared with equal dosage of DA-9601, and BJS-mix001 50 mg/kg showed slighter effects as compared with omeprazole 10 mg/kg, in the present study. The results obtained in this study suggest that BJS-mix001 showed favorable effects in the indomethacin induced gastric damages mediated by strengthening of the antioxidative defense systems.

• 조명전기설비학회논문지
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• 제21권3호
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• pp.132-141
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• 2007

최근 경제 발전으로 인한 전력 에너지 소비 증가로 발전선비의 확충이 요구되는 상황이다. 그러나 화석연료고갈 및 지구환경문제로 대형 화력 발전설비의 확충이 어려워지고 있다. 따라서 발전부지 확보가 용이하고 환경오염의 위험이 적은 분산전원에 대한 관심이 한층 더 고조되고 있다. 그러나 이러한 분산전원이 배전계통에 연계되면 전압변동, 고조파, 보호협조, 고장전류 증가 등의 문제를 일으키므로 이에 대한 적절한 연구가 필요하다. 본 논문에서는 국내 22.9[kV] 배전계통에 다수의 분산전원이 연계되었을 경우, 각 계전기가 감지하는 고장전류의 크기와 방향성을 고려하여 고장 감지 및 고장 지점을 확인하는 방법을 제안하였다. 이를 기반으로 하여 배전계통 보호기기인 자동재폐로 차단기-구분개폐기 보호시스템이 상호협조를 이루기 위한 온라인 보호 협조방안을 제시하였다.

• 셀메드
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• 제10권2호
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• pp.11.1-11.14
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• 2020

Nigella sativa commonly known as Black seed, Black cumin or Kalonji (Family Ranunculaceae) is a widely used for its miraculous healing power. Use of N. sativa seeds and oil has splendid historical past in diverse traditional systems of medicine and food. In Tibb-e-Nabwi (Prophetic Medicine), it is considered as one of the greatest forms of healing medicine. Phytochemically; it contains fixed oil, protein, alkaloids saponin and essential oil. Therapeutic properties of this plant are due to the presence of thymoquinone which is one of major active component and has different beneficial properties. In Unani System of Medicine the diseases are treated with nontoxic herbal drugs. As per Unani classical literature N. sativa perform various pharmacological actions like carminative, anti-inflammatory, analgesic, diuretic, emmenagogue, galactagogue, expectorant etc. Ample of phytochemical, pharmacological and clinical researches has been executed on N. sativa., which may include antidiabetic, anticancer, immunomodulator, analgesic, antimicrobial, anti-inflammatory, bronchodilator, hepato-protective, renal protective, gastro-protective, antioxidant properties, etc. This review is an effort to summarize the literature on scientific researches of pharmacognostical characteristics, chemical composition and pharmacological activities of the kalonji seeds

• 조명전기설비학회논문지
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• 제29권4호
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• pp.116-125
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• 2015

This paper presents experimental results obtained from actual installation conditions of surge protective devices (SPDs), with the aim of understanding the coordination of cascaded Class I and Class II SPDs. This paper also proposes effective methods for selecting and installing coordinating cascaded SPDs. The residual voltage of each SPD and the energy sharing of an upstream Class I tested SPD and a downstream Class II tested SPD were measured using a $10/350{\mu}s$ current wave. In coordinating a cascaded voltage-limiting SPD system, it was found that energy coordination can be achieved as long as the downstream SPD is a metal oxide varistor with a higher maximum continuous operating voltage than the upstream SPD; however, it is not the optimal condition for the voltage protection level. If the varistor voltage of the downstream SPD is equal to or lower than that of the upstream SPD, the precise voltage protection level is obtained. However, this may cause serious problems with regard to energy sharing. The coordination for energy sharing and voltage protection level is fairly achieved when the cascaded SPD system consists of two voltage-limiting SPDs separated by 3 m and with the same varistor voltage.

• ETRI Journal
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• 제32권5호
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• pp.665-675
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• 2010

Recent research on mobile Internet protocol television and digital right management (DRM) interconnections has focused on multimedia technologies designed to enhance content scalability and adaptive content distribution. However, due to the architectural and scalable limitations, recent systems are not flexible and securable with respect to their adaptive content distribution and protective policy management. Therefore, we propose a content protective multi-agent platform that provides secure multimedia services, correlation management, pattern-based management, and multi-source multi-use (MsMu)-based services. Our architecture, supported by DRM, lets us create a rich set of MsMu-based content protection and seamless multimedia services through the extension of one source multi-use (OsMu)-based content services. We have verified our platform, which provides scalable and securable services with a 17% lower service response time by using a testbed.

• Preventive Nutrition and Food Science
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• 제14권1호
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• pp.37-42
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• 2009

The protective activity of seolitae chungkukjang added with green tea against oxidative stress was investigated under the cellular systems using LLC-$PK_1$ cells. The treatment of 2,2'-azobis(2-aminopropane) dihydrochloride (AAPH) showed increase in lipid peroxidation, and decrease in endogenous antioxidant enzymes activity and cell viability. However, the methanol extract of seolitae chungkukjang inhibited lipid peroxidation by 58.3%, and increased cell viability up to more than 60%. In addition, it enhanced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. Seolitae chungkukjang improved oxidative stress-induced cellular injury through the radical scavenging activities. In particular, the addition of green tea in seolitae chungkukjang showed stronger effect against oxidative stress induced by AAPH. The more addition of green tea resulted in the greater antioxidative effect through elevation in activities of SOD and GSH-Px, and inhibition of lipid peroxidation, eventually leading to increase in cell viability. Theses results suggested that seolitae chungkukjang added with green tea have protective effects from cellular oxidative damage and could be considered as an application for the development of chungkukjang with functionality.

• Preventive Nutrition and Food Science
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• 제15권1호
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• pp.7-13
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• 2010

We investigated whether the fermented soymilk extract (FSE) has protective effects against high glucose-induced oxidative stress in human umbilical vein endothelial cells (HUVECs). FSE was prepared via fermentation of soymilk with Bacillus subtilis followed by methanol extraction. To determine the protective effect of FSE, oxidative stress was induced by exposing of HUVECs to the high glucose (30 mM) for 48 hr. Exposure of HUVECs to high glucose for 48 hr resulted in a significant (p<0.05) decrease in cell viability, catalase, SOD and GSH-px activity and a significant (p<0.05) increase in intracellular ROS level and thiobarbituric acid reactive substances (TBARS) formation in comparison to the cells treated with 5.5 mM glucose. However, at concentration of 0.1 mg/mL, FSE treatment decreased intracellular ROS level and TBARS formation, and increased cell viability and activities of antioxidant enzymes including catalase, SOD and GSH-px in high glucose pretreated HUVEC. These results suggest that FSE may be able to protect HUVECs from high glucose-induced oxidative stress, partially through the antioxidative defense systems.

• Progress in Superconductivity
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• 제5권2호
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• pp.128-131
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• 2004

The resistive superconducting fault current limiters (SFCLs) are very attractive devices for the electric power network. But they have some serious problems when the YBCO thin films were used for the current limiting materials due to the in homogeneities caused by manufacturing process. When the YBCO films have some inhomogeneities, simultaneous quenches are difficult to achieve when the fault current limiting units are connected in series for increasing operating voltage ratings. Magnetic field application is one of the prospective way of inducing simultaneous quenches far the series-connected resistive FCL components. Magnetic field was typically generated by the fault current thorough a coil, which is connected to components of the fault current limiter in series, leaving the problem, which provides significant inductance to the power line and suppresses critical current density of the superconducting components. In this article we investigated the possible application of the protective current transformer (p-CT), which is available current source to the magnetic coil. This system inductively coupled to the circuit, therefore, remarkably reducing impedance to the circuit. The current by the protective current transformer was directly fed to the coil, generating magnetic field large enough to reduce critical current density of the components. This successfully induced simultaneous quenches of the series-connected resistive FCL components.

• Journal of Advanced Marine Engineering and Technology
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• 제20권2호
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• pp.92-92
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• 1996

Recently, with the rapid development in the oceanic systems such as the oceanic structures and vessel, there occurs much interest in the impingement erosion-corrosion. In this paper, Cu-metal was tested by using of erosion apparatus with water-jet type and was investigated under the behaviour of impingement erosion-corrosion according to various environmental conditions, and the properties of Cu-metal were evaluated through the measurement by weight loss, weight loss rate, protective efficiency. The results were compared with those obtained using Cu-metal applied to cathodic protection and Cu-alloys added to Zn or Al-metal. As a basis of those results, the best protective efficiencies could be taken as using cathodic protection method and Cu-alloy with Al & Zn material addings, and will be suggested as the fundamental data of the anti-impingement erosion-corrosion on Cu-metal of impeller material for oceanic centrifugal pump.