• Title/Summary/Keyword: multiple blocks

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Minocycline Directly Blocks Activation of Caspases After Oxidative Stress in PC12 Cells

  • Choi, Yu-Keum;Kim, Gab-Seok;Han, Byung-Hee
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.79.2-79.2
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    • 2003
  • Minocycline is known to protect neurons from microglia-mediated cell death in many experimental models of brain diseases including ischemic stroke, Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), traumatic brain injury, multiple sclerosis, and Parkinson's disease. Activation of caspase-2, 3, 8, and 9 was evident within 2-8 hr following oxidative insult with 0.5 mM hydrogen peroxide in PC12 cells. Minocycline significantly attenuated activation of these caspases up to 18 hr, resulting a significant increase in cell viability as assessed by MTT assay. (omitted)

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Load-Balance-Independent High Efficiency Single-Inductor Multiple-Output (SIMO) DC-DC Converters

  • Ko, Younghun;Jang, Yeongshin;Han, Sok-Kyun;Lee, Sang-Gug
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.3
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    • pp.300-312
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    • 2014
  • A single-inductor multiple-output (SIMO) DC-DC converter providing buck and boost outputs with a new switching sequence is presented. In the proposed switching sequence, which does not require any additional blocks, input energy is delivered to outputs continuously by flowing current through the inductor, which leads to high conversion efficiency regardless of the balance between the buck and boost output loads. Furthermore, instead of multiple output loop compensation, only the freewheeling current feedback loop is compensated, which minimizes the number of off-chip components and nullifies the need for the equivalent series resistance (ESR) of the output capacitor for loop compensation. Therefore, power conversion efficiency and output voltage ripples can be improved and minimized, respectively. Implemented in a 0.35-${\mu}m$ CMOS, the proposed SIMO DC-DC converter achieves high conversion efficiency regardless of the load balance between the two outputs with maximum efficiency reaching up to 82% under heavy loads.

Performance of multiple tuned mass dampers-inerters for structures under harmonic ground acceleration

  • Cao, Liyuan;Li, Chunxiang;Chen, Xu
    • Smart Structures and Systems
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    • v.26 no.1
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    • pp.49-61
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    • 2020
  • This paper proposes a novel high performance vibration control device, multiple tuned mass dampers-inerters (MTMDI), to suppress the oscillatory motions of structures. The MTMDI, similar to the MTMD, involves multiple tuned mass damper-inerter (TMDI) units. In order to reveal the basic performance of the MTMDI, it is installed on a single degree-of-freedom (SDOF) structure excited by the ground acceleration, and the dynamic magnification factors (DMF) of the structure-MTMDI system are formulated. The optimization criterion is determined as the minimization of maximum values of the relative displacement's DMF for the controlled structure. Based on the particle swarm optimization (PSO) algorithm to tune the optimum parameters of the MTMDI, its performance has been investigated and evaluated in terms of control effectiveness, strokes, stiffness and damping coefficient, inerter element force, and robustness in frequency domain. Meanwhile, further comparison between the MTMDI with MTMD has been conducted. Numerical results clearly demonstrate the MTMDI outperforms the MTMD in control effectiveness and strokes of mass blocks. Additionally, in the aspects of frequency perturbations on both earthquake excitations and structures, the robustness of the MTMDI is also better than the MTMD.

Fast Multiple Reference Frame Selection Method Using Neighboring Motion Vectors and Inter-mode Correlation (인접 블록의 움직임 벡터 및 인터모드간 상관관계를 이용한 고속 다중 참조 프레임 선택 기법)

  • Jeong, Chan-Young;Kim, Myoung-Jin;Joo, Won-Hee;Hong, Min-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.8C
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    • pp.764-771
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    • 2009
  • In this paper, we propose a fast multiple reference frame selection method using neighboring motion vectors and the correlation of inter-mode blocks in H.264 video coding. Using the property that an optimal reference frame has the statistical characteristics, the motion estimation of small Inter-block size is estimated from the motion estimation of the larger Inter-block size. Simulation results show that the proposal method decreased the computations about 91%. Without the sacrifice of coding performance, comparing to the H.264 multiple reference picture coding.

Suppression of the High Frequency Distortion by Adjustment of Transconductance of the Diode-Connected Transistor in the Current Mode Max Circuit for Multiple Inputs (다수 입력용 전류모드 Max 회로에서 다이오드결선 트랜지스터의 트랜스컨덕턴스 조정에 의한 고주파 왜곡 억제)

  • 이준수;손홍락;김형석
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.40 no.11
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    • pp.37-44
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    • 2003
  • A distortion suppression technology for employing multiple inputs in 3n+1 type current mode Max circuit is proposed using the adjustment of transconductance. If the number of input blocks of the current mode Max circuit increases, the high frequency distortion in the output signal grows. In this paper, it has been disclosed that the distortion in the multiple input Max circuit is proportional to such accumulated parasitic capacitance, to the derivative of the output signal and also to tile inverse of transconductance of the common diode-connected transistor. The proposed idea is by employing as larger transconductance of the common diode-connected transistor as possible. The effectiveness of the proposed idea has been proved through the HSPICE simulation for the current mode Max circuits with various numbers of input signals.

Cryptographic Key Generation Method Using Biometrics and Multiple Classification Model (생체 정보와 다중 분류 모델을 이용한 암호학적 키 생성 방법)

  • Lee, Hyeonseok;Kim, Hyejin;Nyang, DaeHun;Lee, KyungHee
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.28 no.6
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    • pp.1427-1437
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    • 2018
  • While biometric authentication system has been in general use, research is ongoing to apply biometric data to public key infrastructure. It is a significant task to generate a cryptographic key from biometrics in setting up a public key of Bio-PKI. Methods for generating the key by quantization of feature vector can cause data loss and degrade the performance of key extraction. In this paper, we suggest a new method for generating a cryptographic key from classification results of biometric data using multiple classifying models. Our proposal does not cause data loss of feature vector so it showed better performance in key extraction. Also, it uses the multiple models to generate key blocks which produce sufficient length of the key.

An Efficient Scheme to Achieve Differential Unitary Space-Time Modulation on MIMO-OFDM Systems

  • Liu, Shou-Yin;Chong, Jong-Wha
    • ETRI Journal
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    • v.26 no.6
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    • pp.565-574
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    • 2004
  • Differential unitary space-time modulation (DUSTM) has emerged as a promising technique to obtain spatial diversity without intractable channel estimation. This paper presents a study of the application of DUSTM on multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems with frequency-selective fading channels. From the view of a correlation analysis between subcarriers of OFDM, we obtain the maximum achievable diversity of DUSTM on MIMO-OFDM systems. Moreover, an efficient implementation strategy based on subcarrier reconstruction is proposed, which transmits all the signals of one signal matrix in one OFDM transmission and performs differential processing between two adjacent OFDM blocks. The proposed method is capable of obtaining both spatial and multipath diversity while reducing the effect of time variation of channels to a minimum. The performance improvement is confirmed by simulation results.

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ADS-B based Trajectory Prediction and Conflict Detection for Air Traffic Management

  • Baek, Kwang-Yul;Bang, Hyo-Choong
    • International Journal of Aeronautical and Space Sciences
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    • v.13 no.3
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    • pp.377-385
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    • 2012
  • The Automatic Dependent Surveillance Broadcast (ADS-B) system is a key component of CNS/ATM recommended by the International Civil Aviation Organization (ICAO) as the next generation air traffic control system. ADS-B broadcasts identification, positional data, and operation information of an aircraft to other aircraft, ground vehicles and ground stations in the nearby region. This paper explores the ADS-B based trajectory prediction and the conflict detection algorithm. The multiple-model based trajectory prediction algorithm leads accurate predicted conflict probability at a future forecast time. We propose an efficient and accurate algorithm to calculate conflict probability based on approximation of the conflict zone by a set of blocks. The performance of proposed algorithms is demonstrated by a numerical simulation of two aircraft encounter scenarios.

The Effect of Epidural Ketamine in Complex Regional Pain Syndrome Occuring after Lumbar Epidural Block -A case report- (요부경막외차단술 후 발생한 복합부위 통증증후군에서의 경막외 Ketamine의 효과 -증례 보고-)

  • Ock, Kyung-Jong;Han, Kyung-Rim;Kim, Jin-Soo;Kim, Chan;Kim, Eun-Young
    • The Korean Journal of Pain
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    • v.13 no.2
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    • pp.251-254
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    • 2000
  • A 20-year-old male patient developed severe right leg pain, hyperesthesia and allodynia after multiple lumbar epidural blocks. His pain was neuropathic pain (complex regional pain syndrome type I). The patient was treated with repeated administration of epidural ketamine at the rate of 0.2~0.7 mg/kg on multiple occasions. Complete relief of pain was achieved.

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Multiple Object Tracking using Color Invariants (색상 불변값을 이용한 물체 괘적 추적)

  • Choo, Moon Won;Choi, Young Mie;Hong, Ki-Cheon
    • Proceedings of the Korea Multimedia Society Conference
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    • 2002.11b
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    • pp.101-109
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    • 2002
  • In this paper, multiple object tracking system in a known environment is proposed. It extracts moving areas shaped on objects in video sequences and detects racks of moving objects. Color invariant co-occurrence matrices are exploited to extract the plausible object blocks and the correspondences between adjacent video frames. The measures of class separability derived from the features of co-occurrence matrices are used to improve the performance of tracking. The experimented results are presented.

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