• Title/Summary/Keyword: Life-span

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A Case Study on Corrosion Rates of Concrete Sewer Pipes in Housing Sites (주택단지 오수용 콘크리트 흄관의 부식속도 측정 사례)

  • Kim, Young-Jin
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05a
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    • pp.550-553
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    • 2006
  • This study measured corrosion rates for checking and analysis of Hume pipes in the housing sites. According to the result, Concrete pipe is deteriorating for twenty years by hydrogen sulfide(H2S). Investigation method applied phenolphthalein method(depth of neutrality). Phenolphthalein method measured average depth from concrete surface to coloring point by red after spraying phenolphthalein solution. A result of investigation, Life span of Hume pipe in the housing site is investigated of twenty years.

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Toxicity and Antitumor Activities of Korean Medicinal Plants (I) (한국산 생약의 독성 및 항암 작용 (제1보))

  • Chang, Il-Moo;Chi, Hyung-Joon
    • Korean Journal of Pharmacognosy
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    • v.12 no.3
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    • pp.125-130
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    • 1981
  • Thirty species of Korean medicinal plants which have been frequently used in Oriental herb prescriptions were evaluated on their acute toxicity and potential antitumor activities against P-388 lymphocytic leukemia. The criteria for toxicity evaluation of measuring weight loss, toxicity day survivors and computing log cell kill indicated that 11 species possessed acute toxicity according to the doses administered. No significant antitumor activities were observed while the root of Angelica gigas Nakai (Umbelliferae) exhibited only 24% increased life span.

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A Review on the Development of Hold Clamp for Feeder Distribution Line (급전분기선 지지 크램프 개발에 대한 검토)

  • Park, Weon-Chan;Lee, Jae-Bong;Oh, Sung-Hyo;Park, Jong-Hak
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.1898-1903
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    • 2010
  • The hold clamp which is for holding feeder distribution line in direct current can be lengthened its span of life by inserting insulators(EDPM rubber) through improving its function such as preventing damage from temperature change and electric corrosion. This paper reviews the development background, design, manufacture and performance assessment of the hold clamp inserting insulators to prevent circulating current.

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Analysis of Statically Indeterminate Bearing-Shaft System and Prediction of the Behavior of Ball Bearing (베어링-축계의 부정정계 해석 및 볼베어링의 거동예측)

  • 김완두;한동철
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1993.12a
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    • pp.70-76
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    • 1993
  • From the analysis of shaft-bearing indeterminate system, moment and misalingment angle which was generated in bearing were determined. And the influence of span length between bearings on the fatigue life was established. The equation to estimate the cage rotational speed was proposed, and this equation was verified by the measuring of cage speed and shaft speed. And accoding to quasi-static analysis, the spinning speed of ball was determined.

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Development of Conveyor Belt Monitoring System (컨베이어 벨트상태 모니터링 시스템 개발)

  • 유재상
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.436-436
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    • 2000
  • In order to monitor the belt from being damaged by impact of large lump of materials in ores being transported on conveyor belt, we developed a conveyor belt monitoring system using vision. By the information such as the position and size of the damage of belt obtained by vision system, it is expected that not only the span of belt life will be lengthened, but also this system can enable operators to plan scheduled maintenance and prevent the enlargement of damaged parts in conveyor belt at an early stage

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Molt cycle in Neomysis awatschensis(Crustacea : Mysidacea) based on marsupial development

  • Ma, Chae-Woo;Oh, Chul-Woong;Kim, Jong-Chun
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.10a
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    • pp.317-318
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    • 2001
  • In crustacea the molting cycle is the most important physiological process affecting growth, behaviour, reproduction and population dynamics through their life span. Particularly molt cycle is closely related to reproductive cycle, and it is important to determine the successive stages of molt cycle to understand reproductive phenomena including ovarian cycle and the development of the embryos in the marsupium. (omitted)

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Control of Microgrid System with Super-capacitor and Battery (수퍼 커패시터와 배터리를 이용한 마이크로그리드 시스템의 제어)

  • Choi, Yongoh;Lee, Eonsuck;Chung, Sekyo;Song, Yujin
    • Proceedings of the KIPE Conference
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    • 2013.07a
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    • pp.242-243
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    • 2013
  • This paper presents a voltage and frequency regulation of a Micro-grid using a Battery energy storage system (BESS) and super-capacitor (SPC). The control methods for the both BESS and SPC are proposed to improve the regulation performance and battery life span. The simulation results using the PSCAD/EMTDC are provided to show the effectiveness of the proposed control.

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Screening of Korean medicinal plants for antitumor activity

  • Chang, Il-Moo;Woo, Won-Sick
    • Archives of Pharmacal Research
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    • v.3 no.2
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    • pp.75-78
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    • 1980
  • Potential antinumor activity of sixteen Korean medicinal plants was tested against leukemia SN 36, murine tomor model. Survival studies by measuring life span indicated that Morus alba (Moraceae), Verbascum phlomoides (Scrophulariaceae), Curcuma longa (Zingbieraceae), Torilis japonica (Umbelliferae), Bupleurum falcatum (Umbelliferae) and Codonopsis pilosula (Campanulaceae) exhibited significant antitumor activity with the dose-schedule employed in the experiment. Methanol (70%) extracts of Platycodon gradiflorum (Campanulaceae), Bupleurum longeradiatum (Umbelliferae) and Asiasarum sieboldii (Aristolochiaceae) showed rather potent toxicity.

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