• Title/Summary/Keyword: SCI논문

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A Study on the Moderating Effects of the R&D Fund Management System between National R&D Fund and Research Performance (정부지원 연구비와 연구성과간의 관계에서 연구비관리시스템의 조절효과)

  • Son, Chung Geun
    • Journal of Korea Society of Industrial Information Systems
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    • v.18 no.5
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    • pp.107-117
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    • 2013
  • In order to enhance the performance of National R&D program, it is required not only the R&D funds and human resources, but also the composition of the research environment in which the researchers could fully concentrate on study. Particularly in Korea, executive burdens that arise in the course of the administration of research fund are frequently causing difficulties in concentrating on study. To remove this burden on financial management and maximize the efficiency of research funding, the government has implemented the central management system of the R&D fund. This study analyzed the moderating effects of the centralized management system of the R&D fund on the relationship between government fund and performance of the university research. Based on the analyzed result, this study concluded that the higher level of centralized management system of the R&D fund is implemented, the more influence on research outcomes grow. This study is significant to extend previous research point of view, as well as analyze the practical effect of government policies.

Drag Reduction of a Circular Cylinder With O-rings (O-ring을 이용한 원주의 항력감소에 관한 실험적 연구)

  • Lim, Hee-Chang;Lee, Sang-Joon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.8
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    • pp.1174-1181
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    • 2003
  • The flow around a circular cylinder was controlled by attaching O-rings to reduce drag force acting on the cylinder. Four experimental models were tested in this study; one smooth cylinder of diameter D (D=60mm) and three cylinders fitted with O-rings of diameters d=0.0167 D, 0.05D and 0.067 D with pitches of PPD=2D, 1D, 0.5D and 0.25D. The drag force, mean velocity and turbulence Intensity profiles in the near wake behind the cylinders were measured for Reynolds numbers based on the cylinder diameter in the range of Re$_{D}$=7.8$\times$10$^3$~1.2$\times$10$^{5}$ . At Re$_{D}$=1.2$\times$10$^{5}$ , the cylinder fitted with O-rings of d=0.0167D in a pitch interval of 0.25D shows the maximum drag reduction of about 5.4%, compared that with the smooth cylinder. The drag reduction effect of O-rings of d=0.067D is not so high. For O-ring circulars, as the Reynolds number increases, the peak location of turbulence intensity shifts downstream and the peak magnitude is decreased. Flow field around the cylinders was visualized using a smoke-wire technique to see the flow structure qualitatively. The size of vortices and vortex formation region formed behind the O-ring cylinders are smaller, compared with the smooth cylinder.der.

Is Yi Soyeon an astronaut or a space tourist? : The First Korean Astronaut Debate on the view of ANT (이소연은 우주인인가 관광객인가? : ANT의 관점으로 본 한국최초우주인 논쟁)

  • An, Hyoung-Joon
    • Journal of Science and Technology Studies
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    • v.9 no.1
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    • pp.89-127
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    • 2009
  • The Korean Astronaut Project(KAP) aims to make the first Korean astronaut fly and take part in space activities in the International Space Station(ISS) in April 2008. KAP was on the purpose of studying the requirement to master manned space technologies as part of the long-term basic plan for national space development. However, people criticized that Ms. Yi was a 'space tourist' not an 'astronaut' because KAP was a program for pride, prestige in 21c's new space race, not specifically science and technology. The government emphasized that Yi carried out her 15 experiments in ISS very competently. In contrast people devaluated Yi's space experiments as below the level, though some of them are enough meaningful to be published on SCI journals. Why did the government fail to make people take Ms. Yi as an astronaut? I answer to this question using the notion of "Network Analysis" based on Actor-Network Theory(ANT).

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Numerical and Experimental Analysis of Micro Gas Turbine Heat Transfer Effect (초소형 가스터빈엔진 열전달 현상의 수치적 및 실험적 연구)

  • Seo, Junhyuk;Kwon, Kilsung;Choi, Ju Chan;Baek, Jehyun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.2
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    • pp.153-159
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    • 2015
  • In this study, a 2-W micro-gas turbine engine was designed using micro-electro-mechanical systems (MEMS) technology, and analytical and experimental investigations of its potential under actual combustion conditions were performed. An ultra-micro-gas turbine contains a turbo-charger, combustor, and generator. A compressor, turbine blade, and generator coil were manufactured using MEMS technology. The shaft was supported by a precision computer numerical control machined air bearing, and a permanent magnet was attached to the end of the shaft for generation. An analysis found that the cooling effect of the air bearing and compressor was sufficient to cover the combustor heat, which was verified in an actual experiment.

Research on the Holding Value of Academic Journals Based on the Half-Life Index-Number in Science and Technology (과학기술분야 학술잡지의 반감기 측정에 의한 소장 가치 연구)

  • So, Min-Ho;Ko, Seong-Soon
    • Journal of Korean Library and Information Science Society
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    • v.39 no.4
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    • pp.377-395
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    • 2008
  • This article aims to help decide until when a library has to hold journal volumes for user efficiency by measuring the value of academic journals to find the frequency of journal use over the elapsed time based on the half-life index-number of literature obsolescence by Burton & Kebler. Four general subjects categories in science was analyzed. (4 detailed subjects in mathematics, 12 in physics, 12 in chemistry, 14 in technology was selected.) As a result, citation ages are $20{\sim}29$ years in mathematics, $8{\sim}11$ in physics, chemistry, and technology. Average half-life indexes are 11.22 year in mathematics, 7.5 in physics, 8.4 in chemistry, and 8.88 in technology.

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Decreasing Parameter Decision in Edge Strength Hough Transform (경계선 강도 허프 변환에서 감쇄 파라미터의 결정)

  • Woo, Young-Woon;Heo, Gyeong-Yong;Kim, Kwang-Baek
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.06a
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    • pp.728-731
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    • 2007
  • Though the Hough transform is a well-known method for detecting analytical shape represented by a number of free parameters, the basic property of the Hough transform, the one-to-many mapping from an image space to a Hough space, causes the innate problem, the sensitivity to noise. To remedy this problem, Edge Strength Hough Transform (ESHT) was proposed and proved to reduce the noise sensitivity. However the performance of ESHT depends on the size of a Hough space and image and some other parameters, which play an important role in ESHT and should be decided experimentally. In this paper, we derived a formula to decide decreasing parameter. Using the derived formulae, the decreasing parameter value can be decided only with the pre-determined values, the size of a Hough space and an image, which make it possible to decide them automatically.

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Study of the Supersonic Ejector-Diffuser System with a Mixing Guide Vane (혼합 안내깃을 적용한 초음속 이젝터-디퓨져 시스템에 대한 연구)

  • Kong, Fanshi;Jin, Yingzi;Kim, Heuydong
    • Journal of the Korean Society of Propulsion Engineers
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    • v.17 no.1
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    • pp.52-60
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    • 2013
  • Ejector-diffuser system makes use of high-pressure primary stream to entrain the low-pressure secondary stream through pure shear action between two streams. In general, the flow field in the ejector-diffuser system is highly complicated due to turbulent mixing, compressibility effects. A fatal drawback of the ejector system is in its low efficiency. Many works have been done to improve the performance of the ejector system, but not yet satisfactory. In the present study, a mixing guide vane was installed at the inlet of the secondary stream for the purpose of the performance improvement of the ejector system. A CFD method has been applied to simulate the supersonic flows inside the ejector-diffuser system. The present results obtained were validated with existing experimental data. The mixing guide vane effects are discussed in terms of the entrainment ratio, total pressure loss as well as pressure recovery.

On the historical investigation of Bernoulli and Euler numbers associated with Riemann zeta functions (수학사적 관점에서 오일러 및 베르누이 수와 리만 제타함수에 관한 탐구)

  • Kim, Tae-Kyun;Jang, Lee-Chae
    • Journal for History of Mathematics
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    • v.20 no.4
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    • pp.71-84
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    • 2007
  • J. Bernoulli first discovered the method which one can produce those formulae for the sum $S_n(k)=\sum_{{\iota}=1}^n\;{\iota}^k$ for any natural numbers k. After then, there has been increasing interest in Bernoulli and Euler numbers associated with Riemann zeta functions. Recently, Kim have been studied extended q-Bernoulli numbers and q-Euler numbers associated with p-adic q-integral on $\mathbb{Z}_p$, and sums of powers of consecutive q-integers, etc. In this paper, we investigate for the historical background and evolution process of the sums of powers of consecutive q-integers and discuss for Euler zeta functions subjects which are studying related to these areas in the recent.

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Formula for Equivalent Impulsive Force to Predict Vibrational Response of High-frequency Staircases (고진동수 계단의 진동응답 산정을 위한 등가임펄스 산정식 제안)

  • Kim, Na Eun;Lee, Cheol Ho;Kim, Sung Yong
    • Journal of Korean Society of Steel Construction
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    • v.27 no.2
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    • pp.181-193
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    • 2015
  • High-frequency staircases are widely used nowadays to meet aesthetics and functionality needed in modern architecture. Unfortunately, no design guide is available in domestic practice to predict response or evaluate the vibration performance of high-frequency staircases. SCI-P354 published by the Steel Construction Institute of UK provides the formula for effective impulsive force. However, this formula was shown to overestimate the response of high-frequency staircases excited by fast ascending and descending over 2.2Hz pace frequency because it was developed based on the walking test in a slow pace frequency. This study proposes a semi-analytical formula to predict the response of stiff staircases based on analytical and experimental studies of response acceleration for various walking frequencies covering 1.4~4.5Hz.

The Integrity Verification of Tube-end Sleeve by ECT (와전류탐상검사에 의한 튜브엔드 슬리브 건전성 검증)

  • Kim, Su Jin;Kwon, Kyung Joo;Suk, Dong Hwa;Park, Ki Tae
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.11 no.1
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    • pp.20-24
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    • 2015
  • Steam generator(S/G) tubes in pressurized water reactor (PWR's) are subject to several types of degradation. This degradation includes denting, pitting, intergranular attack(IGA), intergranular stress corrosion cracking(IGSCC), fatigue, fretting and wear. Degradation can be derived from either the primary side(inside) or the secondary side(outside) of the tube. Recent issue for tube degradation in domestic steam generator is the tube end cracking on seal weld region. The seal weld region at the tube end and tube itself is regarded as a pressure boundary between the primary side and the secondary side. One of the Westinghouse Model-F S/G has experienced tube end cracking and its number of plugging approximately becomes to the operating limit up to 5% due to tube end cracking which was reported as SAI/MAI(single/multiple axial indication) or SCI/MCI(Single/multiple circumferential indication) from the results of eddy current testing. Eddy current mock-up test was carried out to determine the origin of cracking whether it is from weld zone area or parent tube. This result was helpful to analyze crack location on ECT data. Correct action on this problem was the installation of tube-end sleeve. Last year, after removing 340 installed plugs from tubes, selected 269 tubes took tube-end sleeve installation. Tube-end sleeve brought pressure boundary from parent tube to installed sleeve tube. Tube-end sleeve has the benefit of reducing outage period and increasing more revenue than replacing S/G. This paper is provided to assist interest parties in effectively understanding this issue.