• Title/Summary/Keyword: 평로

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A Femtosecond Laser Metrology on the Thermal Conductivity of a Nanoscale Superconductor Material (펨토초 레이저를 이용한 나노 스케일 초전도 재료의 열전도율 평가)

  • Kim, Yun Young
    • Journal of the Korean Society for Nondestructive Testing
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    • v.35 no.5
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    • pp.314-320
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    • 2015
  • The present study investigates the thermal characteristics of a nanoscale superconductor material. A thin-film of $YBa_2Cu_3O_7-x$ was deposited on a $SrTiO_3$ substrate by using a pulsed-laser deposition technique and characterized using an ultrafast laser system. In order to extract a thermal conductivity value, a numerical solution for a transient one-dimensional heat conduction equation was obtained using a finite-difference method. The curve-fit shows a value 1.2 W/mK, which is relatively lower than those of bulk materials. This research provides a material property of superconductor thin-film required for the thermal design of micro or nanodevices.

Analysis on Deployment of Fire Service Force in Korea (한국 소방력배치의 실태 분석)

  • Back, Min-Ho;Lee, Hae-Pyeong
    • Fire Science and Engineering
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    • v.20 no.1 s.61
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    • pp.55-70
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    • 2006
  • The purpose of this study is to analyze an adequate deployment of fire service force to be prepared to respond appropriately and effectively in Korea by settlement pattern. In order to examine the deployment of fire service force by the present standard, we analyzed the logical basis and the deployment of fire service force by city and province. We also classified clusters for settlement pattern through the statistical methods and raised several points for the existing deployment model of fire service force by the classified settlement pattern. As a result, it was confirmed that the deployment of fire service force by the settlement pattern was irrelevant to fire service need.

A Study on Improvement of Fire Service Deployment Standard in Korea (한국 소방력배치 기준의 개선에 관한 연구)

  • Lee, Hae-Pyeong;Back, Min-Ho
    • Fire Science and Engineering
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    • v.20 no.1 s.61
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    • pp.28-42
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    • 2006
  • The purpose of this study is to offer the improvement for deployment of fire service force in Korea by settlement patterns on the basis of analysis for the present standard and deployment of fire service force. For the adequate deployment and operation of fire service force by settlement patterns, we carried out the analysis of the present standard calculated with allocation of the authorized strength. We also classified clusters for settlement pattern through the statistical methods. We proposed the standard for deployment of fire service force reflected with environmental and need factors through the introduction of standardized index.

Analysis on Personnel System and Talent Cultivation System of the Tokyo Fire Department (동경소방청의 인사제도 및 인재양성제도의 분석)

  • Lee, Eui-Pyeong
    • Fire Science and Engineering
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    • v.22 no.4
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    • pp.105-114
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    • 2008
  • This study analyzed recruiting system, competence requirement system, promotion system by competence verification, and expert training system in fire officials of the Tokyo Fire Department. The recruiting system is classified into expert and Grade 1, 2, and 3 and all grades are appointed as a fire fighter. According to the competence requirement system, while in office, fire officials who have a certain qualification defined in the recruiting system can change their recruiting classification according to their ability such as Grade $3{\rightarrow}$Grade 2 or 1 or expert, Grade $2{\rightarrow}1$ or expert, or Grade $1{\rightarrow}$expert. The promotion system requires working hard, capability suitable to their grade, and careful verification. Also, a variety of on-site training and qualification systems are provided to reinforce professionalism of staffs and executives.

An Optimal Fixed-lag FIR Smoother for Discrete Time-varying State Space Models (이산 시변 상태공간 모델을 위한 최적 고정 시간 지연 FIR 평활기)

  • Kwon, Bo-Kyu;Han, Soohee
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.1
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    • pp.1-5
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    • 2014
  • In this paper, we propose an optimal fixed-lag FIR (Finite-Impulse-Response) smoother for a class of discrete time-varying state-space signal models. The proposed fixed-lag FIR smoother is linear with respect to inputs and outputs on the recent finite horizon and estimates the delayed state so that the variance of the estimation error is minimized with the unbiased constraint. Since the proposed smoother is derived with system inputs, it can be adapted to feedback control system. Additionally, the proposed smoother can give more general solution than the optimal FIR filter, because it reduced to the optimal FIR filter by setting the fixed-lag size as zero. A numerical example is presented to illustrate the performance of the proposed smoother by comparing with an optimal FIR filter and a conventional fixed-lag Kalman smoother.

A Study on the Current Measurement Using Spun Fiber (Spun 광섬유를 이용한 전류 측정에 관한 연구)

  • Kwon, Won-Hyun;Jeon, Suk-Hee;Kim, Young-Soo;Kim, Yo-Hee;Park, Han-Kyu
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.10
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    • pp.1158-1165
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    • 1988
  • In this paper, the polarization properties of spun fiber due to intrinsic birefringence and magneto-optic effects are theoretically analyzed and experimented. The degree of polarization which indicates the intrinsic birefrigence is measured over 0.818, and the variation of output polarization angle with input polarization angle is measured within 9$^{\circ}$. Compared with single mode fiber, spun fiber is found to have very excellent polarization-maintaining property. Implemented current measurement system using spun fiber can linearly measure the magnetic field up to 20,000 A/m generated by solenoid.

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Sensitivity Analysis of HAZUS Results Attenuation (지진파 감쇄식에 대한 민감도 분석 연구 (HAZUS))

  • Oh, Tae-Seok;Kim, Jun-Kyoung;Kang, Ik-Bum;Yoo, Seong-Hwa
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.247-252
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    • 2006
  • This study analysed the sensitivity of the attenuation functions for the seismic hazard estimation. For the seismic hazard estimation, this study used HAZUS software, which is developed originally by FEMA(USA). The scenario earthquake ($M_w=6.0$) is located the Hongsung area, where one of the recent macro earthquakes occurred in 1978. The area for seismic hazard estimation is assumed to be Boryung city in Choongnam-do. Three attenuation functions were applied for the sensitivity analysis. The results show that the attenuation functions have much influences on the seismic hazard on the various types of buildings. Therefore the attenuation function is very important factor for the seismic hazard estimation.

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A Practical Application on the External Treatment of Acne (A Focus on the Medical Herbs Published in the Woman's Monthly Magazines) (여드름 외용약의 실제적 응용에 관한 고찰(여성 월간지에 여드름 미용도포제로 소개된 본초를 중심으로))

  • Yu Hyun-jung;Choi In-hwa
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.17 no.1
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    • pp.34-44
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    • 2004
  • Objectives: The objective of this study was to teach patients clinically useful external application of acne. Methods: We investigated the effects and manufacturing methods of the medical herbs published in the woman's monthly magazines according to "Zhong-Yao-Da-Ci-Dian(中藥大辭典)". Results: We investigated that Saururus chinensis Baill.(三白草), Houttuynia cordata Thunb.(魚腥草), Coix lachrymajobi L.(薏苡仁) were discovered 3 times, Brassica oleracea L.(甘藍), Raphanus sativus L.(래복), Daucus carota L. var. Sativa DC.(홍래복), Oryza sativa L.(米皮糠), Spinacia oleracea L.(파래), Cucumis sativus L.(黃爪) 2 times, and Glycyrrhiza uralensis Fisch.(甘草), Gallus gallus domesticus Braisson.(?子白), Aloe vera L.(노회), Phascolus radiatus L.(綠豆), Prunus persica Batsch.(桃葉), Lycopersicon esculentum Mill.(番茄), Taraxacum mongolicum Hand.-Mazz.(蒲公英), Prunus armeniaca L.(杏仁), Musa paradisiaca L. var. Sapientum O. ktze.(香蕉) and Malus pumila Mill.(평과) were discovered once in woman's monthly magazine during last two years. According to the effects, we classificated four groups which were defervescence(淸熱), subsidence of edema(消腫), pyorrhea(排膿) and gloss(滋潤) group. Conclusion & discussion : We suggested the use of each medical herbs on the Consensus conference on acne classification. We needed the further study on the manufacturing method, the time of use and the dose

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The Change of the Physical Properties of Rayon/Cotton Blend Fabrics Treated with Cellulase by Addition of Silicon (셀룰라아제 처리시 실리콘 첨가에 따른 레이온/면 혼방직물의 물성변화)

  • 이선화;송화순
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.8
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    • pp.1032-1042
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    • 1998
  • The purpose of this study is to measure, compare, and investigate the physical properties of rayon/cotton blend fabrics treated with cellulase and cellulase & specific degeneration silicon and to present basic data which is in development a value-added fabric. The results are as follows. The condition for the treatment of cellulase was at 55$^{\circ}C$, pH 4 and the weight loss increased as the concentration of cellulase and the treated time increased. On treatment with cellulase, the crossectional view & longitudinal view of fiber noticed remarkable crack as weight loss increased and tensile strength and elongation decreased, and pilling was enhanced remarkably. KOSHI was increased, NUMERI and FUKURAMI were decreased as weight loss increased. In the basic characteristic value of clothing wearning, shape stability and drapability were decreased, but air content was improved. On treatment with cellulase & silicon, the degree of damage in the crossectional view & longitudinal view of the fiber reduced. Tensile strength, elongation, moisture regain improved. KOSHI and FUKURAMI were reduced, NUMERI was improved rather than when it was treated with cellulase. Therefore handle was improved. In the basic characteristic value of the clothing wearing, shape stability, air content, drapability were improved.

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Evaluation of Tool Wear of P/M High Speed Steel Flat Endmill (분말 고속도공구강 평엔드밀의 공구마멸 평가)

  • Jung, Ha-Seung;Ko, Tae-Jo;Kim, Hee-Sool;Bae, Jong-Soo;Kim, Yong-Jin
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.4
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    • pp.154-160
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    • 2002
  • Powder metallurgy(P/M) process has been used for the production of high performance high-speed steels. P/M high speed steel has more uniform and fine microstructure than those of conventional wrought products. Therefore, it offers distinct advantages over conventional tool steels. The superior uniformity of composition and fine microstrucure lead to excellent toughness and less distortion during heat treatment, which in turn can reduce total grinding costs and provides other benefits, such as uniform hardness and increased tool life. From these reasons, milling, hole machining, broaching, and gear manufacturing tools are major applications of P/M high-speed steels. In this research, we evaluated tool wear of flat endmill which is made of P/M high-speed steel from the view point of cutting tool performance.