• Title/Summary/Keyword: direct determination

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Development of the Corporate Entry In German Cataloging Rules (독일목록규칙에서의 단체기입의 전개과정)

  • Kim Tae-Soo
    • Journal of the Korean Society for Library and Information Science
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    • v.19
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    • pp.113-149
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    • 1990
  • The RAK has in general adopted the provisions of the paris principles to a far greater extent than many other cataloguing codes. And the analyses confirm that the determination of the main entries in German cataloging rules is a rather complex process and one which can result in inconsistent, arbitrary decisions. And the selection of the main entry requires a considerable amount of decision making which is time-consuming and costly. From the point of view of computers, all entries are equal as points of retrieval. In light of the above considerations the most important recommendation to be made is that the main entry principle be abandoned from cataloging theory and practice and be replaced by the title entry. It would eliminate the need for personal judgments required by the present rule. In so doing, it would bring uniformity and Standardization to cataloging practice. Use of the title entry would reduce the time and effort spent on the selection of the main entry which serves no important purpose in the catalog. Therefore title entry is more developed finding device than author entry in direct approach for document retrieval.

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Blank Design and Strain Prediction in Sheete Metal Forming Process (박판금속 성형공정에서의 블랭크 설계및 변형률 예측)

  • Lee, Choong-Ho;Huh, Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.6
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    • pp.1810-1818
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    • 1996
  • A new finite elemetn approach is introduced for direct prediction of bland shapes and strain distributions from desired final shapes in sheet metal forming. The approach deals with the geometric compatibility of finite elements, plastic deformation theory, minimization of plastic work with constraints, and a proper initial guess. The algorithm developed is applied to cylindrical cup drawing, square cup drawing, and fron fender forming to confirm its validity by demonstratin reasonable accurate numerical results of each problems. Rapid calculation with this algorithm enables easy determination of various process variables for design of sheet metal forming process.

Direct Determination of Cationic Disordering in Sodium Bismuth Titanate

  • Choi, Si-Young;Ikuhara, Yuichi
    • Applied Microscopy
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    • v.42 no.3
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    • pp.164-173
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    • 2012
  • The relaxor ferroelectric feature in lead-free perovskite oxides, where the dipoles are randomly oriented and they can be feasibly aligned parallel to the external bias, is attracting lots of attention in the field of piezoelectric materials science, since it is one of candidates to replace the toxic lead-based materials that are still being commercially used. However, the origin of relaxor characteristic and its related atomic structure are still ambiguous. In this study, $Na_{1/2}Bi_{1/2}TiO_3$, chosen as a model relaxor system, was found to exhibit a cationic-disordered atomic structure; and furthermore the nonpolar atomic structure and its related oxygen tilting were ascertained via annular bright field imaging skill. We also found that this cationic disordering gives rise to the local formation of atomic vacancies.

Precision Determination of Structure Displacement using LIDAR (라이다를 이용한 구조물 변위의 정밀계측)

  • Lee Hong-Min;Park Hyo-Seon;Lee Im-Pyeong;Lee Sang-Joo
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2006.04a
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    • pp.223-228
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    • 2006
  • Monitoring structures is important to maintain the safety and serviceability of the structures. The maximum displacement in the structure should be precisely and frequently monitored because it is a direct assessment index indicating its stiffness. However, no practical method has been developed to monitor such displacement precisely, particularly for high-rise buildings and long span bridges because they cannot be easily accessible. To overcome such difficult accessibility, we propose to use a LIDAR system that remotely samples the surface of an object using laser pulses and generates the coordinates of numerous points on the surface. By analyzing the LIDAR points sampled from the surfaces of a deformed structure, we can precisely determine the displacement of the structure. In this study, we thus develop a novel method based the LIDAR system and perform an indoor experiment to prove its performance. This experimental results strongly supports that the displacement measurement using the LIDAR system are enough accurate to be used for structural analyses.

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The Selection of Sample Injection Modes and Its Effect on the Calibration Bias in S Gas Detection by Gas Chromatography (GC의 주입방식 차에 따른 고농도 악취황 성분의 검량오차 연구 : 주입부피의 고정방식 대비 주입농도의 고정방식 간 비교연구)

  • Kim Ki-Hyun;Choi YJ
    • Journal of Korean Society for Atmospheric Environment
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    • v.21 no.2
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    • pp.269-274
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    • 2005
  • In this work, analytical bias arising from the gas chromatographic determination of sulfur compounds was evaluated by the application of direct loop injection method to the GC/PFPD detection of four sulfur compounds including H$_{2}$S, CH$_{3}$SH, DMS, and DMDS. For the proper evaluation of analytical uncertainties involved in GC calibration, we employed two comparative techniques of calibration at fxed concentration injection (CFCI) vs calibration at fixed volume injection (CFVI) method. The results of our study indicate that CFCI method exhibits very poor sensitivity due to the matrix effect with varying injection volumes. On the other hand, as CFVI method overcomes such limitation, it can be used to obtain very accurate quantification of S compounds at their high concentration levels above a few to a few tens ppb.

Frequency Response Based Multi-Objective Design Toolbox for PID Controller (PID 제어기의 주파수응답 기반 다목적 설계도구)

  • Jin, Lihua;Lim, Yeon-Soo;Kim, Young-Chol
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.10
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    • pp.1869-1875
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    • 2008
  • Recently, a direct data-driven synthesis of a proportional integral derivative(PID) controller for a linear time-invariant(LTI) plant was presented in [1]. The authors showed that a complete set of PID controllers achieving robust performance and stability can be calculated directly from frequency response(FR) data without an identified transfer function model. However, it is not convenient to use this method because it requires complicated numerical algorithms to find specific frequencies which are solutions of an identical equation. The method also requires determination of the boundary of the controller's parameters from a finite set of FR data. In this paper, we present the development of a user-friendly Matlab toolbox based on the method in [1]. This toolbox allows us to obtain a complete three-dimensional(3-D) graphical solution of PID controllers that meet multiple design objectives. Several examples are given to demonstrate the use of the toolbox.

An Evaluation of Fracture Toughness for SS400 Steel by R-curve and DCPD (R-곡선과 직류전위차(DCPD)에 의한 SS400강의 파괴인성 평가)

  • Jang Seok-Ki;Han Min-Su
    • Journal of Advanced Marine Engineering and Technology
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    • v.29 no.8
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    • pp.855-861
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    • 2005
  • Fracture toughness defined near the initiation of stable crack growth is investigated by R-curve and Direct Current electric Potential Determination(DCPD) under mode I plane strain conditions for CT specimen with 25.4mm thickness of SS400 steel. Fracture toughness. $J_{IC}$lit near crack tip of CT specimen by R-curve is 17.14 $kg_{f}/mm$ and however. its value by DCPD is 22.82 $Rg_{f} mm$ The value of fracture toughness by DCPD is larger than that by R-curve. Therefore, it is suggested that the evaluation of fracture toughness by R-curve is optimum than by DCPD, when considering amount of crack growth about each of fracture toughness.

A Study on Determining Optimal Gate Positions for Cavity Fill-Uniformity in Injection Molding Design (사출성형 설계에서 캐비티 충전 균형을 위한 수지 주입구의 최적 위치 결정에 관한 연구)

  • Park, Jong-Cheon;Seong, Yeong-Kyu
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.9 no.6
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    • pp.21-28
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    • 2010
  • This study shows an optimization procedure for an automatic determination on the gate position to ensure the fill-uniformity within a part cavity by using the injection molding simulation. For an optimization, the maximum pressure-difference within a part cavity induced at the stage of filling is used to evaluate degree of fill-uniformity. In addition, a direct search scheme based on the reduction of design space is developed and applied in the optimization problem. This corresponding proposed methodology was applied in the optimization on the gate location for a CD-tray molding, as a result, showed the improvement of the fill-uniformity within the cavity.

Sizing of Spray Particles Using Image Processing Technique

  • Lee, Sang-Yong;Kim, Yu-Dong
    • Journal of Mechanical Science and Technology
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    • v.18 no.6
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    • pp.879-894
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    • 2004
  • The image processing technique is simple and, in principle, can handle particles with various shapes since it is based on direct visualization. Moreover, a wide measurement area can be covered with appropriate optical arrangement. In the present paper, various techniques of image processing for sizing and counting particles are reviewed and recent developments are introduced. Two major subjects are discussed in detail: identification of particles (i.e., boundary detection and pattern recognition) and determination of in-focus criteria. Finally, an overall procedure for image processing of spray particles is suggested.

Optical Observations with Milliarcsecond Resolution of Stars, Their Environments and Companions

  • Sanborn, Jason J.;Zavala, Robert T.
    • Journal of Astronomy and Space Sciences
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    • v.29 no.1
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    • pp.63-67
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    • 2012
  • Observations with milliarsecond resolution using the Navy Optical Interferometer have been obtained for a number of stellar systems which include high-mass binaries, eclipsing binaries, and radio stars. These observations also reveal the previously unseen companions in single-lined spectroscopic binaries via directly measured flux ratios. We will present examples of published and ongoing research efforts of these systems to illustrate how an optical interferometer contributes to our knowledge of stars, their environment, and companions. These studies include a conclusive revealing of the previously unseen companion in the single-lined binary ${\Phi}$ Herculis, the direct determination of orbital parameters in the wide and close orbits of Algol, and revealing the orbit of ${\beta}$ Lyrae with spatially resolved images of the $H{\alpha}$ emission.