• Title/Summary/Keyword: TOAD

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Analysis of effects of the arc-funace on the power system Considering the toad pattern of arc-funace (아크로 부하패턴을 고려한 전력계통 전압변동 분석)

  • Park Hyun Taek;Kim Jae Chul;Son Hak Sig;Kug Im Sang;Oh Dong hwan
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.295-297
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    • 2004
  • Arc-furnace is one of the large loads in the electric power system. When the arc-furnace operates, it may cause a bus voltage fluctuation in the power system, because it consumes a lot of reactive power. In this paper, we simulated this phenomenon by using a PSAF program with on-site measured arc-furnace load. The simulated results show that the fluctuation of bus voltage adjacent the arc-furnace was varied from $4.3\%\sim7.8\%$ the normal voltage because of reactive power consumption by arc-furnace. Therefore, we expect this study will come into use as the basic information on the probability of the demand control

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A Study on the Ovarian Cycle of Asian Toad (Bufo gargarizans) (두꺼비 (Bufo gargarizans) 난소주기에 관한 연구)

  • Park, Se-Hwa;Ko, Sun-Kun
    • Korean Journal of Environmental Biology
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    • v.33 no.4
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    • pp.419-424
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    • 2015
  • In order to determine the ovarian cycle of Asian Toad, Bufo gargarizans, the developmental stage based on the gonadosomatic index (GSI), size of follicle oocytes in ovary and vitellogenesis for adult females were investigated all around the year. The weight of ovary and GSI were the lowest from April, and all follicle oocytes exist in the pre-vitellogenic form, indicating that the vitellogenesis was suspended. The follicle oocytes in early-vitellogenic stage appeared in ovary during may when the weight of ovary and GSI start to increased, and the follicle oocytes in mid-vitellogenic and pre-vitellogenic stages existed during June and the weight of ovary and GSI also increased. This indicates that vitellogenesis has been carried out actively during this period. The follicle oocytes in mid-vitellogenic stage and late-vitellogenic stage when the vitellogenesis was also completed existed on September. Post-vitellogenic follicle oocytes after vitellogenesis started to appear from October and rapidly increased from December in hibernation. The full grown follicle oocytes existed during February, indicating the ovarian cycle that all follicle oocytes in ovary are developed separately, not synchronized, during the growing period of follicle oocytes and the post-vitellogenic follicle oocytes are maintained the ovulation period.

Development of the Management Tool for S&T information in distributed retrieval database (분산 저장된 과학기술정보 서비스를 위한 검색 데이터베이스 관리 도구의 설계 및 개발)

  • Lee, Seok-Hyoung;Yoon, Hee-Jun;Yeo, Il-Yeon;Choi, Sung-Pil;Yoon, Hwa-Mook
    • Proceedings of the Korea Contents Association Conference
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    • 2006.11a
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    • pp.677-681
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    • 2006
  • In this paper, we suggest the GUI Management Tool, named K-Manager, for management and service of science and technology information that stored in distributed retrieval databases. Generally, it must be adapted retrieval database system for web based S&T contents service. But, It is inconvenient contents manager or the system administrator controls information easily, because it does not support the S&T information management process like TOAD, which can use for the relation database, in information retrieval database system. Using K-Manager, content manager can process the S&T content and system manager can manage the databases easily. The proposed tool active controls information effectively which is stored in the distributed retrieval database which guarantee the safety management of the contents stored in database and operate retrieval with efficient performances. Our tool consists of two sub systems, one is content manager, the other is database manager for YESKISTI based on KRISTAL-IRMS.

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Growth Arrest by Bufonis Venenum is Associated with Inhibition of Cdc2 and Cdc25C, and Induction of p21WAF1/CIP1 in T24 Human Bladder Carcinoma Cells (섬수 추출물에 의한 T24 인체 방광암세포의 증식억제에 관한 연구)

  • Park Tae Yeol;Park Cheol;Yoon Hwa Jung;Choi Yung Hyun;Ko Woo Shin
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.5
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    • pp.1449-1455
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    • 2004
  • Bufonis venenum (dried toad venom; Chinese name, Chan su) is a traditional Chinese medicine obtained from the skin venom gland of the toad. It has long been used in treating arrhythmia and other heart diseases in China and other Asian countries. Additionally, Bufonis venenum has been reported to selectively inhibit the growth of various lines of human cancer cells. In the present study, it was examined the effects of extract of Bufonis venenum (EBV) on the growth of human bladder carcinoma cell line T24 in order to investigate the anti-proliferative mechanism and induction of apoptosis by EBV. Treatment of T24 cells to EBV resulted in the growth inhibition, morphological change and induction of apoptotic cell death in a dose-dependent manner. Flow cytometric analysis revealed that EBV treatment caused G2/M phase arrest of the cell cycle and down-regulation of cyclin A, cyclin B1 and Cdc2, which was associated with a marked up-regulation of cyclin-dependent kinases (Cdks) inhibitor p21 (WAF1/CIP1) in a p53-independent manner. The Cdc25C expression was also significantly inhibited by EBV treatment, however Wee1 kinase expression was not affected. The induction of apoptotic cell death by EBV was connected with down-regulation of anti-apoptotic Bcl-XS/L expression without alteration pro-apoptotic Bax expression. Taken together, these findings suggest that EBV may be a potential chemotherapeutic agent for the control of human bladder carcinorma cells and further studies will be needed to identify the active compounds that confer the anti-cancer activity of EBV.

Nutritional and Biochemical Studies on the Pollen toads -1. Studies on Lipid Compositions of Sunflower Pollen toad and Effects of Its Pollen toad on Liver Cholesterol Metabolism in Mouse- (화분립(花粉粒)의 영양생화학적(營養生化學的) 연구(硏究) -1. 해바라기 화분립(花粉粒)의 지질조성(脂質組成)과 Mouse 간장(肝臟) 콜레스테롤 대사(代謝)에 미치는 영향(影響)-)

  • Chung, Yung-Gun;Yoon, Soo-Hong;Kwon, Jung-Sook;Bae, Man-Jong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.13 no.2
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    • pp.169-174
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    • 1984
  • For the purpose of investigating whether the administration of sunflower pollen load has any influence upon liver cholesterol metabolism in mouse, lipids were isolated from sunflower pollen load, identified and quantitated by thin-layer and gas liquid chromatographies. We also studied changes in liver cholesterol level in mouse according to the amount and the period of pollen load administration. Lipids of sunflower pollen load were constituted 84.10f of neutral lipid, 10.50% of glycolipid and 5.40% of phospholipid. The main fatty acid contents of neutral lipid, glycolipid and phospholipid were ranged 28.48 to 33.70% of linoleic acid, 12.90 to 47.50% of palmitic acid ana 11.20 to 12.20% of oleic acid, however, phospholipid contained more palmitic acid than the other lipids. The body weight of the Pollen fed mouse significantly increased during experimental Period in comparison with control group. From the fact tat the ratio of liver weight to body weight of pollen fed mouse was smaller than that of control group, it was proved that liver lipid metabolism of pollen fed mouse was more active than that of control group. During early experimental period, liver cholesterol level had been increased according to pollen load administration(P.O), and then the level decreased rapidly to the similar level to that of control group at the end of the period.

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Creep Crack Growth Properties of Low Pressure Turbine Rotor Steel under Constant Load and Ct

  • Jeong, Soon-Uk
    • International Journal of Precision Engineering and Manufacturing
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    • v.3 no.2
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    • pp.95-101
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    • 2002
  • The propagation rate(da/dt) prediction parameter and the microstructure properties of creep crack in domestic 3.3NiCrMov steel were investigated at 550$\^{C}$ by using 0.5" CT specimen under constant load(4090N) and constant Ct(300∼4000N/mhr) condition that was maintained during crack growth of 1mm distance. C* usually increased with crack length though load was reduced in order to maintain constant Ct value as crack growth and considerably showed the scatter band, but Ct depended on load line displacement rate and represented a good relation with da/dt. At constant toad and Ct region, crack growth slope was 0.900 and 0.844 each, in the other hand C* slope was 0.480. Fully coalesced area(FCA) ahead of crack tip was increased as Ct value increase to the critical value, and after that value FCA decreased. The average diameter ditribution of cavity in FCA showed the greatest value about 1.5 ㎛ when Ct=2000N/mhr. The increasing of Ct in FCA view point enlarged the size of damage area and the size reached to maximum 800 ㎛ when Ct=2000N/mhr.

RT- PCR Analysis of Vitellogenin Gene Expression in Bombina orientalis (무당개구리 비텔로제닌 유전자의 발현의 RT- PCR 검출법)

  • 계명찬;이명식;강희정;정경아;안혜선
    • Korean Journal of Environmental Biology
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    • v.22 no.2
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    • pp.329-335
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    • 2004
  • To develop a biomarker for the monitoring of the contamination of estrogenic endocrine disrupters in the aquatic environment, reverse transcription -polymerase chain reaction (RT-PCR) analysis of vitellogenin (Vg) mRNA expression was optimized in Bombina orientalis, a Korean red bellied toad species. Based on partial cDNA sequences of both Vg and beta actin genes of B. orientalis, specific primers for RT-PCR of Vg and beta actin mRNAs were developed. Semiquantitative RT-PCR of the Vg mRNA in liver was optimized using a beta actin mRNA as an internal control in both sexes. In female RT-PCR using $1\;\mu{g}$ of the liver cDNA resulted in a linear increment in the PCR product of Vg from 18 to 34 cycles of amplification. In male, on the contrary, the RT- PCR product was first detected at 30 cycles of amplification and a linear increment was observed from 30 to 40 cycles of amplification, suggesting that male B. orientalis expresses minute amount of Vg mRNA which is a $2^{-12}$ equivalent of female. In conclusion, the optimized protocol for semiquantitative RT-PCR analysis of Vg mRNA level in B. orientalis male liver will be useful for the environmental monitoring the xenoestrogen contamination in the freshwater environment in Korea.

Tip Leakage Flow on the Transonic Compressor Rotor (천음속 회전익에서의 누설유동)

  • Park, Jun-Young;Chung, Hee-Taeg;Baek, Je-Hyun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.1
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    • pp.84-94
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    • 2003
  • It is known that tip clearance flows reduce the pressure rise, flow range and efficiency of the turbomachinery. So, the clear understanding about flow fields in the tip region is needed to efficiently design the turbomachinery. The Navier-Stokes code with the proper treatment of the boundary conditions has been developed to analyze the three-dimensional steady viscous flow fields in the transonic rotating blades and a numerical study has been conducted to investigate the detail flow physics in the tip region of transonic rotor, NASA Rotor 67. The computational results in the tip region of transonic rotors show the leakage vortices, leakage flow from pressure side to suction side and their interaction with a shock. Depen ding on the operating conditions, toad distributions and the position of shock-wave on the blade surface are very different close to the blade tip of the transonic compressor rotor. The load distribution and the shock-wave position close to the blade tip had the close relationship with the starting position of leakage vortex and the direction of leakage flow.

A Genetic Approach for Intelligent Load Redistribution Method in Heterogeneous Distributed System (이질형시스템에서 지능적인 부하재분배를 위한 유전적 접근방법)

  • Lee Seong-Honn
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.6 no.6
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    • pp.506-512
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    • 2005
  • Load redistribution algorithm is a critical factor in computer system. In a receiver-initiated Toad redistribution algorithm, receiver(underloaded processor) continues to send unnecessary request messages for load transfer until a sender(overloaded processor) is found while the system load is light. Therefore, it yields many problems such as low cpu utilization and system throughput because of inefficient inter-processor communications until the receiver receives an accept message from the sender in this environment. This paper presents an approach based on genetic algorithm(GA) for dynamic load redistribution including self-adjustable in heterogeneous distributed systems. In this scheme the processors to which the requests are sent off are determined by the proposed GA to decrease unnecessary request messages.

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The Effect of overcoming the TRAIL resistance through bufalin in EJ human bladder cancer cell (EJ 인간 방광암 세포에서 bufalin 의 TRAIL 저항성 극복 효과)

  • Hong, Su Hyun
    • Herbal Formula Science
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    • v.25 no.2
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    • pp.145-154
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    • 2017
  • Objectives : Bufalin is one of the bioactive component of 'Sum Su (蟾酥)', which is obtained from the skin and parotid venom gland of toad. Bufalin has been known to possess the inhibitory effects on cell proliferation and inducing apoptosis in various cancer cells. The tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) has concerned, because it can selectively induce apoptotic cell death in many types of malignant cells, while it is relatively non-toxic to normal cells. Here, we investigated whether bufalin can trigger TRAIL-induced apoptotic cell death in EJ human bladder cancer cells. Methods : Effects on the cell viability and apoptotic activity were quantified using MTT assay and flow cytometry analysis, respectively. To investigate the morphological change of nucleus, DAPI staining was performed. Protein expressions were measured by immunoblotting. Results : A combined treatment with bufalin (10 nM) and TRAIL (50 ng/ml) significantly promoted TRAIL-mediated growth inhibition and apoptosis in EJ cells. The apoptotic effects were associated with the up-regulation of death receptor proteins, and the down-regulation of cFLIP and XIAP. Moreover, our data showed that bufalin and TRAIL combination activated caspases and subsequently increased degradation of poly(ADP-ribose) polymerase. Conclusions : Taken altogether, the nontoxic doses of bufalin sensitized TRAIL-mediated apoptosis in EJ cells. Therefore, bufalin might be an effective therapeutic strategy for the safe treatment of TRAIL-resistant bladder cancers.