• Title/Summary/Keyword: 수명율

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장거리 표면 플라즈몬과 금속-액체의 계면현상

  • 백문구;이재형;장준성
    • Proceedings of the Optical Society of Korea Conference
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    • 1988.06a
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    • pp.132-134
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    • 1988
  • 얇은 금속면의 얀쪽 표면에 유전율이 같은 물질을 두는 감쇄 전반사 방법에 의하면 수명이 긴 표면 플라즈몬이 생성될수 있다. 이럼엄을 이용하여 금속표면과 접한 액체에서의 라만 산란의 증가를 얻을수 있다.

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Mechanical Deterioration of Overhead Transmission Lines by Forest Fires (산불에 의한 가공 송전선로의 기계적 열화 특성)

  • 김영달;김성덕;심재명;정동화;강지원
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.6
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    • pp.26-34
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    • 2000
  • The considerations for remaining life of ACSR (Aluminum Stranded Conductors Steel Reinforced) in transmission lines have become gradually important to hold reliability and stability of power supply. The remaining life of ACSR exposed to the atmosphere for a long period may rely on deterioration caused by environmental indices such as atmospheric corrosion, galvanic corrosion, crevice corrosion and fatigue corrosion. One of reduction of useful life in overhead transmission lines built on the ridge of mountain is often caused by forest fires.This paper deals with investigation of strength deterioration performance of ASCR due to fires through several testing and analyzing data for tension load and extension of blazed ACSR. Test samples are ACSR 480[$\textrm{mm}^2$] conductors, which are artificially fired to regular durations. Mechanical properties such as tension load and extension for fired ACSR conductors are tested and estimation functions for mechanical performances corresponding to fire duration are determined. As a result, it can be verified that both tension load and extension of ACSR are reduced by increasing fire duration. Hence, it is obvious that ACSR due to forest fires may lead to mechanical deterioration.

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Postharvest Physiology and Prolonging Vase Life of Cut Freesia (Freesia refracta) (절화 프리지아의 수확후 생리 및 수명연장)

  • Kwon, Hye Jin;Hwang, Moon Joo;Kim, Ki Sun
    • Horticultural Science & Technology
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    • v.17 no.3
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    • pp.361-364
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    • 1999
  • This study was conducted to examine the effects of pulsing treatment and to develop techniques treated right after harvest by grower for extending vase life and improving flower quality in cut freesia. Thirty minutes dipping treatment of STS 2 mM followed by 20 hr pulsing in sucrose 10% + BA 10 ppm + 8-HQS 300 ppm solution showed the best results in vase life and flower quality of cut freesia when kept in vase water. This pretreatment extended vase life by 24.7% than control, and improved quality of cut freesia significantly in flower diameter, percent flowering (35.4%), fresh weight, water uptake, and carotenoid content, and depressed ethylene production and respiration rate.

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Maximum Lifetime Geocast Considering Link Error Rates in Ad-Hoc Networks (Ad-hoc 네트워크에서 최대 네트워크 수명과 링크 에러율을 고려한 지오캐스트)

  • Lee, Ju-Young
    • Journal of the Korea Society for Simulation
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    • v.15 no.3
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    • pp.69-77
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    • 2006
  • Geocasting is a form of communication that transmits messages to all nodes within a given geographical region(i.e., the geocasting region). Most of conventional onery aware protocols were based on shortest-hop routing that is, they minimized the cost in terms of the distance and total transmission energy not considering both the residual energy at each node and the link error ratio when selecting the routes for communication. In this paper we propose a MLRG(Maximum Lifetime Reliable Geocast) protocol for energy-efficient and reliable geocasting in Ad-hoc networks. The proposed MLRG, a position-based and routing-based geocasting algorithm, maximizes the network lifetime using newly defined cost function and selecting the energy balanced routes on the basis of each node's residual energy, and provides a reliable communication considering the link error ratio.

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Effects of some insect growth regulators on adult and egg viability of the house fly, Musca domestica L. applied via larval medium (유충의 먹이에 처리한 IGR계 살충제가 집파리의 성충과 부화율에 미치는 영향)

  • Park, Chung-Gyoo;Kim, Doo-Ho
    • The Korean Journal of Pesticide Science
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    • v.3 no.1
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    • pp.78-83
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    • 1999
  • Sublethal effects of imidacloprid (30 and 100 ppm) and insect growth regulators; flufenoxuron (3 and 10 ppm), triflumuron (10 ppm), and teflubenzuron (3 ppm), were tested by treatment via larval rearing medium of a housefly, Musca domestica, in laboratory. Pupal weight was significantly reduced by treatment to the 3rd larvae with high concentrations of imidacloprid (100 ppm) and flufenoxuron (10 ppm), and the adults that survived the flufenoxuron 10 ppm treatment deposited significantly fewer eggs compared with controls and other treatments. Adult longevity and egg viability, however, were not affected by any of the treatments.

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Studies on the Manufacturing of Carbon Bond Graphite Crucible (카아본 본드형 흑연 도가니 제조에 관한 연구)

  • 김충일;김문수
    • Journal of the Korean Ceramic Society
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    • v.13 no.1
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    • pp.11-19
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    • 1976
  • This study was focused on the improvement of production techniques of small crucibles in relation with the appropriate selection of raw materials, various batch compositions and physical and chemical characteristics of the crucibles. Various tests gave the optimum batch composition for the carbon bond graphite cructble as follows: Pyontaek graphite flake (refractory aggregate) : 40Part Silicon carbide: 15Part Tar pitch (binder) : 11Part Inorganic additives (to improve the oxidation resistance) : 15 Part Cryolite : 3 Part Ferro manganese : 2 Part Ferrosilicon : 25 Part Crucibles pressed with 400kg/$\textrm{cm}^2$ at 12$0^{\circ}C$. and fired in reducing atmosphere at 120$0^{\circ}C$ brought the most favorable results as follows: Bulk density : 2.31 Apparent density : 2.58 Porosity : 15.2% Oxidation loss at 1, 50$0^{\circ}C$. for 3 hrs : below 3.77% Water absorption : 6.01% Compressive strength : 438kg/$\textrm{cm}^2$ Tensile strength : 256kg/$\textrm{cm}^2$.

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Effect of Popcorn, Wolbachia Variant, on Development and Reproduction in Drosophila melanogaster (Wolbachia 변이종 Popcorn이 초파리의 발육과 생식에 미치는 영향)

  • 한상미;민경태;한명세;이상철
    • Korean journal of applied entomology
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    • v.39 no.3
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    • pp.193-197
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    • 2000
  • Wolbachia, vertically transmitted bacterial endosymbionts, is known to induce cytoplasmic incompatibility (CI), parthenogenesis, or feminization in some insect species. The Wolbachia found to exist symbiotically as a non-virulent form in Drosophila melanogaster, however popcorn is a lethal strain of Wolbachia, which causes tissue degeneration and early death of its adult host. Popcorn-infected flies showed the delayed duration of an egg and larvae, and their pupal period and life span reduced. The oviposition and egg-hatching rate of popcorn-infected flies were decreased 15% and 80%, respectiv~ly, compared to those of the normal Wolbachia-infected flies. The pupation and emergence rates of popcorn-infected flies were 67% and 65%, respectively. When popcorn-infected flies were crossed with Wolba-chia-infected flies, and vice versa, both crosses resulted in a significant reduction in egg production, egg¬hatching, pupation, and emergence rate, and their progeny revealed the popcorn syndrome. When popcorn-infected male flies were crossed with uninfected females, popcorn was not detected in their progeny. Popcorn also maternally transmitted in flies, but it did not induce CI and affected on its host life cycle as a virulence.

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A Comparative Study on the Analysis Methods of Degradation Data under Random Coefficient Model (확률계수 열화모형하에서 열화자료의 분석방법 비교 연구)

  • Jo Yu-Hui;Seo Sun-Geun;Lee Su-Jin
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2006.05a
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    • pp.117-123
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    • 2006
  • 최근 들어 전통적인 (가속)수명시험으로도 고 신뢰도 제품의 신뢰도 평가가 힘들므로 제품의 성능열화를 관측하여 수명 정보를 추정하는 열화 시험에 대한 관심이 증대되고 있다. 본 논문은 대수정규분포를 따르는 확률계수 열화율 모형 하에서 분포 모수 및 수명분포의 분위수를 추정하는 세 가지 통계적 분석법(근사적, 해석적, 수치적 방법)의 통계적 성능을 비교하였다. 즉, 다양한 수치실험상황 하에서 모형에 포함되는 (측정)오차의 영향을 고려하여 세 방법의 우월성을 조사하였다.

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A Study on the Half-life of Library and Information Science Literature Published in Korea (한국(韓國) 문헌정보학(文獻情報學) 문헌의 반감기(半減期) 연구)

  • Ko, Mi-Young
    • Journal of Information Management
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    • v.24 no.4
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    • pp.24-42
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    • 1993
  • This study examines the obsolescence of library and information science literature published in Korea, analysing citations appeared in major periodicals of 1992. Periodicals, languages, and forms of cited literatures are analyzed to find the half-life and the annual aging factors of Korean library and information science literature and then synthesized.

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