• Title/Summary/Keyword: resistance sources

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The Packaging Technology Thermoelectric Generator (열전모듈을 이용한 발전기의 패키징)

  • 한경목;황창원;백동규;최승철
    • Journal of the Microelectronics and Packaging Society
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    • v.7 no.3
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    • pp.1-6
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    • 2000
  • A simple and compact type of thermoelectric generator was developed as the energy saving system using waste hot water and low temperature waste heat sources. Sixteen of Bi-Te thermoelectric modules were packaged in series for thermoelectric conversion system using hot water as heat source. The thermoelectric generator shows the power output of about 4.5 W with the temperature difference of about 75 K at 40 $\Omega$ and 0.35 A for the electrical resistance and current of the used thermoelectric module, respectively.

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김치 Starter 용으로 분리한 효모의 동정

  • Kim, Hye-Ja;Lee, Cheol-Soo;Kim, Young-Chan;Kang, Sang-Mo
    • Microbiology and Biotechnology Letters
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    • v.24 no.4
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    • pp.430-438
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    • 1996
  • The eleven strains, which could be used lactic and acetic acids as carbon sources, were isolated from kimchi and identified; the strains were facultative microorganisms which could be grown at low temperature (10$\circ$C) and around pH 3.2. As results of morphological, biochemical and physiological tests, 5 species of 3 genera were identified as Debaryomyces coudertii, Pichia edia, Pichia chambardii, Pichia haplophilia and Saccharomyces fermentati. Each strain was grown in basal media. In acidic resistance and acid utilization test, Saccharomyces sp. YK- 17 and Saccharomyces fermentati YK-19 were grown well in basal and YM media containing 0.3% lactic acid. And two strains were grown in basal and YM media containing O.3% lactic acid and 0.6% acetic acid. Since strain YK-19 was grown better at 10$\circ$C than that in 25$\circ$C, strain YK-19 was known to be a psychrophilic strain.

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Methodology on Improving Vibration Characteristics of Servo Write Fixture (서보라이트 픽스쳐의 진동 특성 개선 방법)

  • Yoon, Tae-Yong;Ku, C.P. Roger;Hanlon, Andrew K.;Taylor, Charles L.
    • Transactions of the Society of Information Storage Systems
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    • v.7 no.2
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    • pp.47-52
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    • 2011
  • This paper presents a method to improve vibration characteristics of servo track write (STW) fixture. STW fixtures supported by flexible mounts are subject to various vibration sources. Using Finite element analysis (FEA) vibration modes of the fixture are identified. The FEA results suggest certain vibration modes be reduced through design change of flexible mounts to improve vibration responses of the fixture. Based on layered flexible mounts theory a parametric study on shear and bending stiffness is performed to obtain a suitable flexible mount design leading to increased resistance to rocking motion. Experiments confirm improvement of vibration characteristics and drive performance through new mounts design.

Agent-Based Distance Relaying Algorithm for Phase-to-Ground Faults (에이전트 환경에서의 1선지락 거리계전 알고리즘)

  • Hyun, Seung-Ho;Jin, Bu-Gun;Lee, Seung-Jae
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.11
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    • pp.1885-1891
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    • 2007
  • This paper presents a distance relaying algorithm for phase-to-ground faults in transmission lines under Multi-Agent protection environment. In normal condition, a distance relay agent stores the latest states, e.g., voltage of source side, voltage of the opposite side and the loading conditions, etc., through communication between the agents. Once a fault occurs, the relay calculates the fault location using the knowledge about the states just before the fault happens. This stand-alone operation is to improve reliability under the fault condition at which the accuracy or time required for communication may not be guaranteed. The mathematical expression of fault location is derived through loop analysis, before hand, in the manner that both fault current from the opposite end and fault resistance are included implicitly so that their effects are minimized. The suggested algorithm is applied to a typical transmission system with two power sources on both ends to show its effectiveness.

A Phenomenologic Study on the Children's Living under the Institutional Care (시설아동의 삶(현상학적 접근))

  • Kim, Kwuy-Bun;Kim, Mee-Young
    • Journal of East-West Nursing Research
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    • v.6 no.1
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    • pp.23-36
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    • 2001
  • The purpose of this study was to discover knowledge about the sources and meanings of the children's living who is under the care of welfare institution. Participants were high school girls in Kwangju who offered unstructured description of their experience through interviews. The research was performed from March 2001 to September 2001. The results, analyzed and interpreted according to Gorgi's method of phenomenology, describe the structure of the phenomenon "living experience of the children under the institution care" with a relational perspective. The analysis revealed seven core themes : (1) anguish of heart against custom of institution, (2) resistance against their livelihood, (3) mortification on the distorted prejudice, (4) desire to escape, (5) fearfulness for the unreliable future, (6) self-pity, (7) challenge to the future. The foregoing argument suggest that children under the institutional care be supported by more mental health intervention and nurses be disciplined by supportive conversation technique.

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A Method for Real Time Monitoring of Oxide Thickness in Plasma Electrolytic Oxidation of Titanium

  • Yoo, Kwon-Jong;Lee, Yong-K.;Lee, Kang-Soo
    • Corrosion Science and Technology
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    • v.9 no.1
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    • pp.8-11
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    • 2010
  • During PEO (plasma-electrolytic-oxidation) treatment of titanium, the relationship between the thickness of oxide film and the measured electrical information was investigated. A simple real time monitoring method based on the electrical information being gathered during PEO treatment is proposed. The proposed method utilizes the current flowing from a high frequency voltage source to calculate the resistance of an oxide film, which is converted into the thickness of an oxide film. This monitoring method can be implemented in PEO system in which an oxide film is grown by constant or pulsed voltage/current sources.

Influence of Alkali-free based-Accelerator on the Expansion Behaviors of Cement Matrices with Different $C_3A$ Content under Sulfate Attack ($C_3A$량이 상이한 시멘트 경화체의 황산염 팽창 거동에 대한 알카리프리계 급결제의 영향)

  • Lee, Seung-Tae;Kim, Dong-Kyu;Lee, Kyu-Pil;Jung, Ho-Seop;Park, Kwang-Pil;Kim, Seong-Soo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.953-956
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    • 2006
  • Sulfate resistance of mortar specimens with or without alkali-free accelerator exposed to sulfate solutions for 360 days was investigated. Test results confirms a negative effect of alkali-free accelerator on the sulfate deterioration, irrespective of attacking sources. Based on the ASTM C1012 expansion test, the experimental findings demonstrated that higher $C_3A$ content in cement led to the higher expansion, especially in the mortar specimens with alkali-free accelerator.

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A Novel Distance Relaying Algorithm in a Multi-Agent Protection System of transmission line (Multi-Agent 송전계통 보호시스템에서의 새로운 거리계전 알고리즘)

  • Moon, H.K.;Jin, B.G.;Hyun, S.H.;Lee, S.J.
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.217-219
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    • 2003
  • This paper presents a distance relaying algorithm for a transmission line protection with MAS. First, the voltage and fault current of the opposite side are represented as a function of those of the measuring end using source voltages of both ends. These voltages are assumed to be obtained from the transformers protecting agents, periodically in normal state. Then, the fault location expression, independent of fault resistance, is derived with voltage and current in only one end of faulted line used. The suggested algorithm is applied to a simple system with two power sources to show its effectiveness.

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Development of the High Performance Thermoelectric Modules for High Temperature Heat Sources

  • Jinushi, Takahiro;Okahara, Masahiro;Ishijima, Zenzo;Shikata, Hideo;Kambe, Mitsuru
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.79-80
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    • 2006
  • From a viewpoint of heat stress at high temperatures and contact thermal resistance, it is confirmed that the optimal structure is the skeleton structure using Cu substrate on the cooling side, which has excellent heat conductivity and the optimal installation method is to adopt a carbon sheet and a mica sheet to the high temperature side, where Si grease is applied to the low temperature side, under pressurized condition. The power of the developed modules indicated 0.5W in an $FeSi_2$ module and 3.8 W with a SiGe module at 823K, respectively.

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A Case Study on the Fire of Factory Buildings in Korea

  • Jee, Nam-Yong;Lee, Kyung-Ku;Suh, Chee-Ho
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.450-455
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    • 1997
  • According to the fire statistics of the Ministry of Home Affairs, the fire ratio in factories, work places and warehouses shows 21.5% among total fire of buildings except the fire on cars or other fires. Especially, the buildings like factories and warehouses, which have a lot of ignitable sources and thus always have a strong possibility of fire, are needed to have well planned strategy in terms of life safety and property protection. In this respect, the present paper analyses the existing fire cases in factories, finds out the fire properties of factory buildings, and evaluates the codes concerning fire resistance and fire severity.

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