• Title/Summary/Keyword: Rotation performance

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Performance Evaluation of Inelastic Rotation Capacity of Special Moment Frame Connections (보-기둥 접합부를 가진 철근 콘크리트 모멘트 골조의 비탄성 회전 능력에 대한 평가)

  • Lee, Ki-Hak
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.05a
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    • pp.688-691
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    • 2004
  • This study summarizes results of a research project aimed at investigating the inelastic rotation capacity of beam-column joints of reinforced concrete moment frames. A total of 28 specimens were classified as special moment frame connections based on the design and detailing requirements in the ACI 318-99 provisions. Then, the acceptance criteria, originally defined for steel moment frame connections in the AISC-97 Seismic Provisions, were used to evaluate the joint connections of concrete moment frames. Twenty seven out of 28 test specimens that satisfy the design requirements for special moment frame structures provided sufficient strength and are ductile up to a plastic rotation of $3\%$ without any major degradation in strength.

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Omni-directional Mobile Robot for 2D Translation and Rotation of a Puppet using Magnet (줄 인형의 2차원 이동 및 회전을 위한 자석기반 전 방향 로봇시스템)

  • Kim, Byeong-Yeol;Han, Young-Jun;Hahn, Hun-Soo
    • The Journal of Korea Robotics Society
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    • v.5 no.4
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    • pp.326-331
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    • 2010
  • Marionette controlling robot has a problem that generates interference in rotation and intersection, therefore, the research on the independent shifter to move freely on the stage is required. Connecting omni-directional mobile robot with marionette controlling robot can solve this problem. Omni-directional mobile robot makes itself rotate and translate in 2D plane freely. Magnetic device is used to connect the moving part with the control part of the robot to minimize the intereference generated by the movement of robot. When robot moves, it can move to all directions with the suitalbe setting of banlance power. The moment of inertia is minimized by dividing the robot to the upper and lower parts in the marionette performance stage. Rotation and interference problem of independent omni-wheel Robot can be solved by using the permanent magnet. The efficiency and safety of the marionette controlling robot is proved by the experiment.

Sector Investment Strategy with the Black-Litterman Model (블랙리터만 모형을 이용한 섹터지수 투자 전략)

  • Song, Jung-Min;Lee, Young-Ho;Park, Gi-Gyoung
    • Korean Management Science Review
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    • v.29 no.1
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    • pp.57-71
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    • 2012
  • In this paper, we deal with a sector investment strategy by implementing the black-litterman model that incorporates expert evaluation and sector rotation momentum. Expert evaluation analyzes the relative performance of the industry sector compared with the market, while sector rotation momentum reflects the price impact of significant sector anomaly. In addition, we consider the portfolio impact of sector cardinality and weight constraints within the context of mean-variance portfolio optimization. Finally, we demonstrate the empirical viability of the proposed sector investment strategy with KOSPI 200 data.

Biodegradation of Aromatic Compounds from Soil by Drum Bioreactor System

  • Woo, Seung-Han;Park, Jong-Moon
    • Journal of Microbiology and Biotechnology
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    • v.14 no.3
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    • pp.435-441
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    • 2004
  • A drum bioreactor was used for the treatment of sandy soil contaminated with three kinds of aromatic compounds (phenol, naphthalene, and phenanthrene), and its performance was evaluated in two different operation modes; intermittent and continuous rotation of drum. When the drum bioreactor was operated with one rotation per day, the microbial growth was relatively low, and most of the compounds remaining in soil, except naphthalene of 90 mg/kg dry soil, disappeared mainly due to volatilization. In contrast, when the drum was continuously rotated at 9 rpm (rotation/min), the number of microorganisms was drastically increased and nitrate was consumed for growth as a nitrogen source. Phenol and phenanthrene were removed at rates of 56.7 mg/kg dry soil/day and 3.2 mg/kg dry soil/day, respectively.

Development of Robust-to-Rotation Iris Feature Extraction Algorithms For Embedded System (임베디드 시스템을 위한 회전에 강인한 홍채특징 추출 알고리즘 개발)

  • Kim, Shik
    • The Journal of Information Technology
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    • v.12 no.4
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    • pp.25-32
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    • 2009
  • Iris recognition is a biometric technology which can identify a person using the iris pattern. It is important for the iris recognition system to extract the feature which is invariant to changes in iris patterns. Those changes can be occurred by the influence of lights, changes in the size of the pupil, and head tilting. This paper is appropriate for the embedded environment using local gradient histogram embedded system using iris feature extraction methods have implement. The proposed method enables high-speed feature extraction and feature comparison because it requires no additional processing to obtain the rotation invariance, and shows comparable performance to the well-known previous methods.

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A study on the improvement of polishing surface using Oscillation-type tool and AE sensor (요동형 공구와 AE센서를 이용한 연마면 향상에 관한 연구)

  • 김정욱;김성렬;안중환
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1682-1687
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    • 2003
  • Die polishing technology is very critical to determine quality and performance of the final products. Generally, the rotation-type tool is used most widely in the polishing process. However it is difficult to make the mirror surface, because the method using the rotation-type tool causes a lot of tiny scratch on the polished surface. This paper proposes a new method using the oscillation-type tool that reduces the scratch and improves the surface roughness. As result. the mirror surface was able to obtain by using the oscillation-type tool. AE is known to be closely related to material removal rate(MRR). As the surface is rougher, MRR gets larger and AE increase. The surface roughness can be indirectly estimated using the AE signal measured during automatic die polishing process. In this study. an AE sensor based monitoring system was developed to investigate the relation the level of AE RMS with the surface roughness during polishing process.

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A method of constructing fuzzy control rules for electric power systems

  • Ueda, Tomoyuki;Ishigame, Atsushi;Kawamoto, Shunji;Taniguchi, Tsuneo
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1371-1376
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    • 1990
  • The paper presents a method of constructing simple fuzzy control rules for the determination of stabilizing signals of automatic voltage regulator and governor, which are controllers of electric power systems. Fuzzy control rules are simplified by considering a coordinate transformation with the rotation angle .theta. on the phase plane, and by expanding the range of membership functions. Also, two rotation angles .theta. $_{1}$ and .theta. $_{2}$ are selected for the linearizable region and the nonlinear one of the system, respectively. Here, .theta. $_{1}$ is chosen by the pole assignment method, and .theta. $_{2}$ by a performance index. Fuzzy inference is applied to the connection of two rotation angles .theta. $_{1}$ and .theta. $_{1}$ by regarding the distance from the desired equilibrium point as a variable of condition parts. The control effect is demonstrated by an application of the proposed method to one-machine infinite-bus power system.

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PROPOSAL OF AMPLITUDE ONLY LOGARITHMIC RADON DESCRIPTER -A PERFORMANCE COMPARISON OF MATCHING SCORE-

  • Hasegawa, Makoto
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.450-455
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    • 2009
  • Amplitude-only logarithmic Radon transform (ALR transform) for pattern matching is proposed. This method provides robustness for object translation, scaling, and rotation. An ALR image is invariant even if objects are translated in a picture. For the object scaling and rotation, the ALR image is merely translated. The objects are identified using a phase-only matched filter to the ALR image. The ratio of size, the difference of rotation angle, and the position between the two objects are detected. Our pattern matching procedure is described, herein, and its simulation is executed. We compare matching scores with the Fourier-Mellin transform, and the general phase-only matched filter.

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High-Performance Givens Rotation-based QR Decomposition Architecture Applicable for MIMO Receiver (MIMO 수신기에 적용 가능한 고성능 기븐스 회전 기반의 QR 분해 하드웨어 구조)

  • Yoon, Ji-Hwan;Lee, Min-Woo;Park, Jong-Sun
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.3
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    • pp.31-37
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    • 2012
  • This paper presents an efficient hardware architecture to enable the high-speed Givens rotation-based QR decomposition. The proposed architecture achieves a highly parallel givens rotation process by maximizing the number of pivots selected for parallel zero-insertions. Sign-select lookahed (SSL)-CORDIC is also efficiently used for the high-speed givens rotation. The performance of QR decomposition hardware considerably increases compared to the conventional triangular systolic array (TSA) architecture. Moreover, the circuit area of QR decomposition hardware was reduced by decreasing the number of flip-flops for holding the pre-computed results during the decomposition process. The proposed QR decomposition hardware was implemented using TSMC $0.25{\mu}m$ technology. The experimental results show that the proposed architecture achieves up to 70 % speed-up over the TACR/TSA-based architecture for the $8{\times}8$ matrix decomposition.

Side Information Transmission using Reference Symbol in PTS Scheme (PTS 방식에서 기준 심볼을 이용한 부가정보 전송)

  • 유흥균;박종현;박진수
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.15 no.4
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    • pp.414-420
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    • 2004
  • Partial transmit sequence(PTS) scheme has been widely studied to reduce the peak-to-average power ratio(PAPR) of Orthogonal frequency-division multiplexing(OFDM) signal since it is flexible ad any spectral regrowth is not made. A necessity of the PTS scheme is to transmit the side information about the phase rotation factors for correct OFDM symbol recovery. In this paper, a new side information embedded PTS scheme using the reference symbols is proposed fur the PAPR reduction and the BER(bit error rate) performance is analyzed when the erroneous side information is received. In this proposed method, the information about the rotation factors is expressed by the phase of reference symbols. The proposed method maintains the same PAPR reduction performance as the conventional PTS scheme and OFDM symbols are correctly recovered by the side information to meet the required BER level, which is verified via the computer simulation. Also, it is shown that the proposed method can be easily realized and can be used for all kinds of digital modulation formats in the OFDM communication system.