• Title/Summary/Keyword: positions

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A Study on Luminescent Characteristics according to Crystal Defect of ZnS Powder Phosphors (ZnS 형광체 분말의 결정결합에 따른 발광특성연구)

  • 박용규;성현호;조황신;양해석;이종찬;박대희
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.10
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    • pp.876-882
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    • 2000
  • ZnS phosphors were sintered at vacuum atmosphere, Sintered under the temperature of 950$\^{C}$, ZnS phosphors were grown into the sphalerite structure and two emission peaks were observed at the positions of 460nm and 528nm of the emission spectra. Sintered over the temperature of 1050$\^{C}$, there were simultaneously the sphalerite and wurtize structure in the ZnS phosphors and three emission peaks were observed at the positions of 440nm and 515nm of emission spectra. The emission peaks of 460nm obsrved under the sphalerite structure and 440nm observed under the wurtize structure were due to the vacancy of Zn formed in the ZnS phosphors. The emission peaks of 528nm observed under the sphalerite structure and 515nm observed under the wurtize structure wre caused by the radiative transitions from the level of the vacancy of S formed in the ZnS phosphors to the valance band.

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A Study of Surface Stress Effects on Equilibrium States of thin Nanofilm (나노박막의 표면응력에 의한 평형상태에 대한 연구)

  • Kim, Won-Bae;Cho, Maeng-Hyo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.4
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    • pp.331-334
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    • 2009
  • In this paper, we present a surface relaxation model in atomistic calculations for thin nanofilms. This surface relaxation model is very simple model which have only two degrees of freedoms to determine the atomic positions of nanofilms. Whereas in conventional molecular statics simulations, the same number of degrees of freedoms at all atom positions are used as unknown variables. In order to prove the reliability of the presented model, we present the results of self-equilibrium strain calculations with the surface parameters obtained from this model.

A Study on Effect of Recirculated Exhaust Gas upon Wear of Cylinder Liner and Piston in Diesel Engines

  • Bae, Myung-Whan;Tsuchiya, Kazuo
    • Journal of Mechanical Science and Technology
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    • v.15 no.11
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    • pp.1524-1532
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    • 2001
  • The effects of recirculated exhaust gas on the wear of cylinder liner and piston were experimentally investigated by a two-cylinder, four cycle, indirect injection diesel engine operating at 75% lo ad and 1600 rpm. For the purpose of comparison between the wear rates of the two cylinders with and without EGR, the recirculated exhaust gas was sucked into one of two cylinders after the soot in exhaust emissions was removed by an intentionally designed cylinder-type scrubber equipped with 6 water injectors(A water injector has 144 nozzles of 1.0 mm diameter), while only the fresh air was inhaled into the other cylinder. These experiments were carried out with the fuel injection timing fixed at 15.3$^{\circ}$ BTDC. It was found that the mean wear rate of cylinder liner with EGR was greater in the measurement positions of the second half than those of the first half, that the mean wear rate without EGR was almost uniform regardless of measurement positions, and that the wear rate of piston skirt with EGR increased a little bit, but the piston head diameter increased, rather than decreased, owing to soot adhesion and erosion wear, and especially larger with EGR.

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Development of a Real Time Three-Dimensional Motion Capture System by Using Single PSD Unit (단일 PSD를 이용한 실시간 3차원 모션캡쳐 시스템 개발)

  • Jo, Yong-Jun;Oh, Choon-Suk;Ryu, Young-Kee
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.11
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    • pp.1074-1080
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    • 2006
  • Motion capture systems are gaining popularity in entertainment, medicine, sports, education, and industry, with animation and gaming applications for entertainment taking the lead. A wide variety of systems are available for motion capture, but most of them are complicated and expensive. In the general class of optical motion capture, two or more optical sensors are needed to measure the 3D positions of the markers attached to the body. Recently, a 3D motion capture system using two Position Sensitive Detector (PSD) optical sensors was introduced to capture high-speed motion of an active infrared LED marker. The PSD-based system, however, is limited by a geometric calibration procedure for two PSD sensor modules that is too difficult for common customers. In this research, we have introduced a new system that used a single PSD sensor unit to obtain 3D positions of active IR LED-based markers. This new system is easy to calibrate and inexpensive.

A Few Suggestions For The Arbitrator To Manage The Arbitration Procedure In Favor Of The Parties -Focused on KCAB's Arbitration Procedure- (중재인의 중재절차 진행상 유의사항에 관한 연구 - 대한상사중재원의 절차를 중심으로 -)

  • Lee, Joo-Won;Shin, Koon-Jae
    • Journal of Arbitration Studies
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    • v.22 no.1
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    • pp.23-41
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    • 2012
  • Arbitration provides quicker resolution and may also limit the erosion of business relationships that is often the result of prolonged litigation. The process of arbitration typically involves four phases: 1) selection of arbitrator(s) and opening statement of positions by the parties; 2) rebuttal of opposing positions; 3) interviews, hearings, and information gathering; and 4) rendering of a decision and issuance of the arbitrator's award. A distinctive feature of arbitration is the party's ability to select the arbitrator and the process and rules that will be followed at the hearing. Once that process has been completed, the parties are in the hands of the arbitrator or tribunal. The arbitrator's duty goes on the arbitration procedure efficiently and renders arbitration award. This article discussed various ways the arbitrator leads to a shorter, less risky arbitration, which benefits the parties. We recommend the arbitrator the following comments; Before the hearing the arbitrator decides to whether an arbitration agreement is valid, and a scope of authorities of him in advance. In the hearing, the arbitrator gives both parties a sufficient opportunity to produce evidence, witnesses, and make their arguments. Lastly, the arbitrator need to be cautious in guiding the parties toward an amicable settlement.

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Calculation of the Ideal Positions of Hydrogen Atoms in Compounds (화합물내에서의 수소원자의 이상적 위치계산)

  • Suh Il-Bwan;Kim Kyung-Han;Oh Mi-Ran;Park Koon Ha;Kim Moon-Jib
    • Korean Journal of Crystallography
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    • v.8 no.1
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    • pp.59-63
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    • 1997
  • A method for the calculation of the idealized hydrogen positions in the following seven different kinds of compounds has been shown: (1) tertiary C-H, (2) secondary C-H, (3) $CH_3$ group with tetrahedral angles, (4) aromatic C-H or amide N-H, (5) O-H group with X-O-H angle tetrahedral, (6) terminal $X=CH_2$ or $X=NH_2^+$ with the hydrogen atoms in a plane and (7) acetylenic C-H with X-C-H linear.

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The Carcinogenic Region of Benzo[a]pyrene Metabolites and Its Molecular Complex with Guanine and Adenine (Benzo[a]pyrene 대사체의 발암활성 영역 및 DNA 염기와의 분자착물의 배향)

  • Kim, Jong Moon;Son, Gwan Su;Doh, Seong Tak;Kim, Seog Kyu;Park, Byung Kak
    • Journal of the Korean Chemical Society
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    • v.40 no.4
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    • pp.229-234
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    • 1996
  • Carcinogenicities of Benzo[a]pyrene(BP) and its metabolites were investigated by PM3. The 4, 5, 5a, and 6 positions forming transbutadiene(TB) frame in BP have been proved to be carcinogenic region by LUMO. We have found that the carcinogenic region of BP-triol, ultimate cacinogen, is shifted from 4, 5, 5a, and 6 positions of precarcinogen to 10, 10a, 12c, and 12b ones. The appreximate charge transfer quantities turned out to have the largest value between HOMO of Guanine and LUMO of BP-triol corresponding to TB region on each other.

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Measurement of Infrared Signature according to the Operating Condition and Location of a Small Scale Engine (축소형 제트 엔진의 구동 조건 및 측정 위치에 따른 적외선 신호 측정 연구)

  • Gu, Bonchan;Jegal, Hyunwook;Baek, Seung Wook;Choi, Seongman;Kim, Won Cheol
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2017.05a
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    • pp.596-597
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    • 2017
  • In this study, the measurements of infrared (IR) signature were carried out using a small scale engine with the variation of the engine performance and target positions in the exhaust plume. The operating conditions of the engine were kept constant for each test, and the measured positions were sapced at refular intervals from the nozzle exit. The measured IR signature was calibrated by using a blackbody. The results of infrared signature measurements are shown in three bands for analysis of spectral characteristics. As the engine performance decreased and the distance from the nozzle exit increased, the IR signature decreased and the level of decrease varied according to the bands.

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An Experimental Study on the Pumping Characteristics of Diffuser/Nozzle Based Piezoelectric Micropumps with Different Geometries and Operating Conditions (압전 구동방식 마이크로 펌프에서 기하학적 형상과 작동조건에 따른 점핑특성에 대한 실험적 연구)

  • Yong, Jung-Kwon;Kim, Chang-Nyung;Kim, Chin-Uck
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.21 no.1
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    • pp.33-40
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    • 2009
  • In the present experimental study, the pumping performances of diffuser/nozzle based piezoelectric micropumps are estimated with different operating factors and geometries. Here, the effects of the input voltage and frequency on the pumping performances have been examined together with the influences of the positions of the inlet and outlet. The results show that the flow rate of the micropump is larger with larger input voltage with the largest flow rates for the frequency to be close to 6.0 Hz all through the current experimental study. Also, it has been found that the positions of the inlet and outlet affect much on the performance of the piezoelectric micropumps. Error estimation has been carried out for the evaluation of the pumping performance in association with the uncertainty of the measurement.

A Study on the Optimal Position of Vehicle Side Mirrors according to the Perception of Visual Information (시각정보의 인식도에 의한 자동차 Side Mirror의 최적 위치결정에 관한 연구)

  • 김도회;이근희
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.14 no.24
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    • pp.123-132
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    • 1991
  • This study deals with the experiment of perceiving visual information according to the positions of vehicle side mirrors. In the design of vehicle, the consideration of safety is very important. Therefore we consider the positions of side mirrors to use visual information effectively which is important factor to driver. This paper presents the position of side mirror to elevate the degree of visual perception for the circumstances of danger by experiments. To exhibit the circumstances of danger. 4 LED(Light Emitted Diode) art located at each side(right. left front. hack) of vehicle. A subject pushes the LED switch to see that if he perceives the circumstance of danger. To record the circumstance of randomly generated danger, computer interface card is used to control 4 LED and swithch on IBM PC/AT Experiments are divided into 2 parts. The 1st experiment present the independence of right & left side mirror. The 2nd experiment present optimal position of right & left side mirror. The vehicle used in experiment is model EL of H Co.. Statistical process of experimental data using SPSS(Statistical Package for Social Sciences)/PC package concludes that 1) the optimal position of right side mirror is 54cm forward of exist position. 2) for the left side mirror, the position of 120cm forward of exist position shows the worst degree of perception. and the optimal position does not exist in statistical meaning.

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