• Title/Summary/Keyword: 고정-고정 보

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A Study on the Asymmetric Preswirl Stator System (비대칭형 전류 고정날개 추진 시스템 연구)

  • Moon-Chan Kim;Jin-Tae Lee;Jung-Chun Suh;Ho-Chung Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.30 no.1
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    • pp.30-44
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    • 1993
  • This paper deals with both experimental and theoretical methods for performance prediction of asymmetric stater propulsion systems which have been used for the purpose of recovery of a propeller slipstream rotational energy due to a stator located in front of the propeller. Using the developed computer code based on the lifting surface theory, theortical investigation on the interaction between the stator and the propeller is provided in order to obtain general insight on the performance characteristics of the propulsion systems in uniform and non-uniform flow. Such theoretical calculations have end agreements with model Inset results. The asymmetric stator would give an efficiency gain of about 6% to the compound propulsor system compared with the single propeller system.

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Design of Bit-Pattern Specialized Adder for Constant Multiplication (고정계수 곱셈을 위한 비트패턴 전용덧셈기 설계)

  • Cho, Kyung-Ju;Kim, Yong-Eun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.11
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    • pp.2039-2044
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    • 2008
  • The problem of an efficient hardware implementation of multiple constant multiplication is frequently encountered in many digital signal processing applications such as FIR filter and linear transform (e.g., DCT and FFT). It is known that efficient solutions based on common subexpression elimination (CSE) algorithm can yield significant improvements with respect to the area and power consumption. In this paper, we present an efficient specialized adder design method for two common subexpressions ($10{\bar{1}}$, 101) in canonic signed digit (CSD) coefficients. By Synopsys simulations of a radix-24 FFT example, it is shown that the proposed method leads to about 21%, 11% and 12% reduction in the area, propagation delay time and power consumption compared with the conventional methods, respectively.

Cipher method of digital voice data using fixed time slot mode in PCM system (고정 타임슬롯 모드를 사용하는 PCM 시스템에서 디지털 음성 데이터 보안 기법)

  • Im, Sung Yeal
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.04a
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    • pp.782-785
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    • 2010
  • 본 논문은 연속된 음성 신호를 전송로 상에 전송하기 위해 음성 신호를 G.711 표준 권고인 PCM으로 다중화한 후 고정 타임슬롯을 배정하여 전송하는 시스템에서 PCM 화된 디지털 음성 데이터를 실시간으로 암호화하여 전송하는 스트림 암호화 기법에 관한 것이다. 실시간으로 처리되는 음성 데이터의 암호화 시에는 하드웨어 방식이 적합한 데, 본 논문에서는 고정 타임슬롯을 배정받는 음성 데이터의 실시간 암호화 기법에 관한 것이다. 일반적으로 아날로그 음성 신호 코딩 시에 국내에서는 북미 방식인 ${\mu}-law$ 코딩 기법을 적용하는 데 이는 표본화한 음성 데이터를 양자화전에 압축하고 복호화 후 신장하는 비선형 양자화 기법을 적용하는 것으로 표본화된 값을 8 비트의 PCM 데이터로 변화하여 E1(2.048Mbps) 급 속도로 전송한다. 본 논문에서는 PCM 전송로 상에 전송되기 전의 직렬 입력 데이터를 암호화 장치를 거쳐 해당 타임슬롯에 해당하는 8 비트의 데이터를 실시간으로 암호화하여 전송로 상으로 전송하고 역으로 수신 단에서는 PCM 전송로를 거친 직렬 입력 데이터를 암호화된 타임슬롯을 판별하여 해당 타임슬롯의 데이터를 복호화하여 원래 데이터를 복원한다. 본 논문에서는 고정 타임슬롯을 배정받은 PCM 데이터를 암호화하여 전송한 후 수신 단에서 복호화 과정을 거친 후 타임슬롯 단위로 데이터 암호화/복호화가 가능함을 보여준다.

In-Plane Buckling Analysis of Curved Beams Using DQM (미분구적법(DQM)을 이용한 곡선보의 내평면 좌굴해석)

  • Kang, Ki-Jun;Kim, Young-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.7
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    • pp.2858-2864
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    • 2012
  • The differential quadrature method (DQM) is applied to computation of the eigenvalues of in-plane buckling of the curved beams. Critical moments and loads are calculated for the beam subjected to equal and opposite bending moments and uniformly distributed radial loads with various end conditions and opening angles. Results are compared with existing exact solutions where available. The DQM gives good accuracy even when only a limited number of grid points is used. More results are given for two sets of boundary conditions not considered by previous investigators for in-plane buckling: clamped-clamped and simply supported-clamped ends.

A Memory-based Learning using Repetitive Fixed Partitioning Averaging (반복적 고정분할 평균기법을 이용한 메모리기반 학습기법)

  • Yih, Hyeong-Il
    • Journal of Korea Multimedia Society
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    • v.10 no.11
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    • pp.1516-1522
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    • 2007
  • We had proposed the FPA(Fixed Partition Averaging) method in order to improve the storage requirement and classification rate of the Memory Based Reasoning. The algorithm worked not bad in many area, but it lead to some overhead for memory usage and lengthy computation in the multi classes area. We propose an Repetitive FPA algorithm which repetitively partitioning pattern space in the multi classes area. Our proposed methods have been successfully shown to exhibit comparable performance to k-NN with a lot less number of patterns and better result than EACH system which implements the NGE theory.

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Robust Gaze-Fixing of an Active Vision System under Variation of System Parameters (시스템 파라미터의 변동 하에서도 강건한 능동적인 비전의 시선 고정)

  • Han, Youngmo
    • KIPS Transactions on Software and Data Engineering
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    • v.1 no.3
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    • pp.195-200
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    • 2012
  • To steer a camera is done based on system parameters of the vision system. However, the system parameters when they are used might be different from those when they were measured. As one method to compensate for this problem, this research proposes a gaze-steering method based on LMI(Linear Matrix Inequality) that is robust to variations in the system parameters of the vision system. Simulation results show that the proposed method produces less gaze-tracking error than a contemporary linear method and more stable gaze-tracking error than a contemporary nonlinear method. Moreover, the proposed method is fast enough for realtime processing.

Fixed-Width Booth-folding Squarer Design (고정길이 Booth-Folding 제곱기 디자인)

  • Cho Kyung-Ju;Chung Jin-Gyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.8C
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    • pp.832-837
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    • 2005
  • This paper presents a design method for fixed-width squarer that receives a W-bit input and produces a W-bit squared product. To efficiently compensate for the quantization error, modified Booth encoder signals (not multiplier coefficients) are used for the generation of error compensation bias. The truncated bits are divided into two groups (major/minor group) depending upon their effects on the quantization error. Then, different error compensation methods are applied to each group. By simulations, it is shown that the performance of the proposed method is close to that of the rounding method and much better than that of the truncation method and conventional method. It is also shown that the proposed method leads to up to $28\%\;and\;27\%$ reduction in area and power consumption compared with the ideal squarers, respectively.

Out-of-Plane Buckling Analysis of Curved Beams Using DQM (미분구적법(DQM)을 이용한 곡선보의 외평면 좌굴해석)

  • Kang, Ki-Jun
    • Journal of the Korean Society of Safety
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    • v.17 no.4
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    • pp.189-195
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    • 2002
  • The differential quadrature method (DQM) is applied to computation of the eigenvalues of out-of-plane bucking of curved beams. Critical moments including the effect of radial stresses are calculated for a single-span wide-flange beam subjected to equal and opposite in-plane bending moments with various end conditions, and opening angles. Results are compared with existing exact solutions where available. The differential quadrature method gives good accuracy even when only a limited number of grid points is used. New results are given for two sets of boundary conditions not previously considered for this problem: clamped-clamped and clamped-simply supported ends.

Parameter-Efficient Multi-Modal Highlight Detection via Prompting (Prompting 기반 매개변수 효율적인 멀티 모달 영상 하이라이트 검출 연구)

  • DongHoon Han;Seong-Uk Nam;Eunhwan Park;Nojun Kwak
    • Annual Conference on Human and Language Technology
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    • 2023.10a
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    • pp.372-376
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    • 2023
  • 본 연구에서는 비디오 하이라이트 검출 및 장면 추출을 위한 경량화된 모델인 Visual Context Learner (VCL)을 제안한다. 기존 연구에서는 매개변수가 고정된 CLIP을 비롯한 여러 피쳐 추출기에 학습 가능한 DETR과 같은 트랜스포머를 이어붙여서 학습을 한다. 하지만 본 연구는 경량화된 구조로 하이라이트 검출 성능을 개선시킬 수 있음을 보인다. 그리고 해당 형태로 장면 추출도 가능함을 보이며 장면 추출의 추가 연구 가능성을 시사한다. VCL은 매개변수가 고정된 CLIP에 학습가능한 프롬프트와 MLP로 하이라이트 검출과 장면 추출을 진행한다. 총 2,141개의 학습가능한 매개변수를 사용하여 하이라이트 검출의 HIT@1(>=Very Good) 성능을 기존 CLIP보다 2.71% 개선된 성능과 최소한의 장면 추출 성능을 보인다.

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