• Title/Summary/Keyword: merit factor

검색결과 125건 처리시간 0.15초

Evaluation of randomness of binary random sequence

  • Harada, Hiroshi;Kashiwagi, Hiroshi;Takada, Tadashi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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    • pp.979-983
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    • 1989
  • This paper proposes a new concept, called merit factor Fr, for evaluating the randomness of binary random sequences. The merit factor Fr is obtained from the expected values of the autocorrelation function of the binary random sequence. Using this merit factor Fr, randomness of the binary random sequences generated by the random sampling method is evaluated.

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카메라 렌즈 설계에서 직교화 방법에 관한 연구 (A study on convergence and stabilization of SVD damped least squares method in the triplet camera lens-system design)

  • 정정복;이원진;김경찬
    • 한국안광학회지
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    • 제1권1호
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    • pp.29-39
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    • 1996
  • Triplet 카메라 렌즈계(f'=50mm, f/3.5)를 통하여 고유값의 중간값은 최적의 감쇠 계수임과, 정규 방정식을 풀 때 SVD 직교화 방법을 적용하면 불량 조건을 제거하여 계산의 정확도를 높일 수 있어서 merit 함수는 최소값에 안정하면서도 빠르게 수렴할 수 있다는 것을 조사하였다. 양호 조건인 triplet 카메라 렌즈계에서 SVD 직교화 방법을 적용한 DLS 법에서 얻은 최소 merit 함수는 가우스 소거법에서 얻은 최소 merit 함수의 97.86%로서 크게 개선되지는 못하였다. 따라서 SVD 직교화 방법을 적용한 DLS 법이 가우스 소거법을 적용한 DLS 법보다 감쇠 계수 적용에 대한 안정성과 수렴속도가 좋으며, 최적화 방법에 적절한 감쇠 계수를 적용시켜주면 최적화 과정의 수렴 속도가 개선됨을 알 수 있었다.

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인터넷 기반 유통경로에 대한 소비자인식의 변화에 관한 실증적 연구 (A Empirical Study on the Changed Consumer Perception to Internet Based Channel)

  • 정기수;문승제
    • 산업융합연구
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    • 제1권1호
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    • pp.143-157
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    • 2003
  • This paper examines the changed consumer perception to internet based channel. Internet based channel has time merit, place merit, assortment merit, compatibility merit, and so on. For seller, in the mean while, it has merits in the way of diminishing physical distribution cost, promotion cost, and reaching globally in the same time. In spite of so many merits of internet based channel, there were many types complain in past. Most of all, consumers expect that it will provide low-price merit to consumer, because it doesn't need shop, warehouse, stock, etc. Based on the empirical analyses in past, it didn't work, especially to price oriented consumer's perception. But in this research, it shows changing consumer's perception. Comparing past data with current data, we found outstanding gross in price related variables figure. But, in goods delivery related factors and personal credit information related factor, consumer recognized much more negatively yet. So, we conclude that even though some factors show improved perception, there are tasks to solve. We will observe the tuning point at that time.

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On desirable conditions for a random number used in the random sampling method

  • Harada, Hiroshi;Kashiwagi, Hiroshi;Takada, Tadashi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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    • pp.1295-1299
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    • 1990
  • A new method called random sampling method has been proposed for generation of binary random sequences. In this paper, a new concept, called merit factor Fn, is proposed for evaluating the randomness of the binary random sequences generated by the random sampling method. Using this merit factor Fn, some desirable conditions are investigated for uniform random numbers used in the random sampling method.

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Hall소자 재료의 특성지수 (The figure of merit for hall element materials)

  • 이정한
    • 전기의세계
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    • 제25권4호
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    • pp.53-58
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    • 1976
  • Criteria and significance of the factor .root..mu..$R_{u}$ or ($R_{u}$/.root.p) in Hall element material selection are discussed. And the chart which is useful to compare the figure of merit F=.root..mu..$R_{u}$ in Hall element materials is presented with the F's for some practical Hall device materials.als.

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우수한 비주기 자기상관 특성을 갖는 새로운 다중 위상 부호열 (New Polyphase Sequence with Good Nonperiodic Autocorrelation Property)

  • 문경하;홍윤표;최기훈;송홍엽
    • 한국통신학회논문지
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    • 제29권7C호
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    • pp.915-920
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    • 2004
  • 본 논문에서는 비주기 자기상관 특성의 중요한 지표가 되는 merit factor의 관점에서 가장 우수한 비주기 자기상관 특성을 갖는 새로운 다중 위상 부호열(polyphase sequence)을 제안한다. 또한, 정수 환(integer residue ring)에서 LFSR(Linear Feedback Shift Register)을 이용한 일반적인 다중 위상 부호열 생성기를 제안하고 제안된 생성기에 기반한 다중 위상 부호열의 선형 복잡도를 분석한다.

The secondary excited induction generator in random wave input system

  • Kim, Moon-Hwan
    • Journal of information and communication convergence engineering
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    • 제7권2호
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    • pp.209-214
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    • 2009
  • The employment of the induction generator is preferable in the natural energy utilization by the minimum maintenance and the mechanical robustness, Another merit is also expected when it is connected to the power network system, because constant-voltage and constant frequency (CVCF) power generation is easily realized in spite of the variation of the rotor speed. However the induction generator needs much amount of the reactive power that reduces power factor in the primary side. The improvement of power factor in the primary side requires large VAR compensator, this point is solved, the merit of the induction machine as a main generator will become more established. This paper proposes a novel approach where the secondary is controlled by a PWM inverter not only to get CVCF power but also to improve the primary power factor. Basically the inverter is controlled so that the field current is supplied from the secondary side in this approach. The required capacity of the inverter is small, because only the slip power is controlled in the secondary side. In the experimental system where the sea wave torque simulator is used, the power factor is well improved by the microcomputer controlled PWM inverter.

Efficient Global Optimization of Periodic Plasmonic Nanoslit Array Based on Quality Factor Analysis

  • Jaehoon Jung
    • Current Optics and Photonics
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    • 제7권3호
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    • pp.248-253
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    • 2023
  • An efficient global optimization approach for a periodic plasmonic nanoslit array based on extraordinary optical transmission within an acceptable time range is proposed using 𝚀 factor analysis method. The particle swarm optimization is employed as a global optimization tool. The figure of merit is defined as a product of transmission peak value and 𝚀 factor. The design variables are the slit width, height, and period of the slit array, respectively. The optical properties such as transmission spectrum and bandwidth are calculated rigorously using the finite element method.

1차원 자성 포토닉 결정의 자기 광학 특성 수치해석 (Numerical Analysis of Magneto-Optic Performance of One-Dimensional Magneto-Photonic Crystal)

  • 박재혁;조재경
    • 한국자기학회지
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    • 제10권3호
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    • pp.99-105
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    • 2000
  • 두 종류의 유전체 층(A: $SiO_2$, B: T $a_2$ $O_{5}$ )을 주기적으로 적층한 구조에, Bi를 다량 치환한 가네트 박막(M: $Y_{1.93}$ B $i_{1.07}$F $e_{5}$ $O_{12}$ )을 결함층으로 삽입한 (A/B)$^{k}$ /M(B/A)$^{k}$ 의 구조를 갖는 1차원 자성 포토닉 결정의 자기 광학 특성을 수치해석하였다. 가시광과 적외선 영역에서 1차원 자성 포토닉 결정의 자성체 층의 두께( $d_{M}$)와 유전체 층의 적층수(k)를 변화시키며, 투과율(T)과 페러데이 회전각($\theta$$_{F}$ ) 및 성능지수(Q)를 조사하였다. 조사한 1차원 자성 포토닉 결정의 각 국재 모드에서의 페러데이 회전각 및 성능지수의 극대값들은 동일 조성의 단층 가네트 박막에 비해 수 배 내지 수 백 배 큰 값이 얻어졌다. 가시광 영역에서는 k = 11이고, $d_{M}$ = 375 nm일때, 최대값 Q = 0.15이 얻어졌다. 이 값은 단층의 가네트 막에 비해 약 30배 큰 값이며, 이 때의 = 720 nm, T = 0.54, $\theta$ = 8.13$^{\circ}$이었다. 적외선 영역에서는 k = 11이고, $d_{M}$ = 800 nm일때 , 최대값 Q = 0.285(단층 가네트 막에 비해 100배 큰 값)이 얻어졌고, 이 때의 = 1114 nm, T = 0.485, $\theta$$_{F}$ = 18$^{\circ}$이었다.

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Figures of Merit of (K,Na,Li)(Nb,Ta)O3 Ceramics with Various Li Contents for a Piezoelectric Energy Harvester

  • Go, Su Hwan;Kim, Dae Su;Han, Seung Ho;Kang, Hyung-Won;Lee, Hyeung-Gyu;Cheon, Chae Il
    • 한국세라믹학회지
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    • 제54권6호
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    • pp.530-534
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    • 2017
  • The figures of merit in the on-resonance and off-resonance conditions ($FOM_{on}$ and $FOM_{off}$) for the piezoelectric energy harvester (PEH) were measured and compared in $[(K_{0.485}Na_{0.515})_{1-X}Li_X](Nb_{0.99}Ta_{0.01})O_3$ (x = 0.04 ~ 0.09) (KNLNT) ceramics with various Li contents. The crystal structure of CuO-doped KNLNT ceramics changes from orthorhombic to tetragonal around the Li fraction of 0.065. The stable temperature range for the tetragonal phase widens to both higher and lower temperatures as Li is substituted. The piezoelectric charge constant ($d_{33}$), electromechanical coupling factor ($k_p$) and mechanical quality factor ($Q_m$) have maximum values at the Li fraction between 0.055 and 0.065 where the phase boundary lies between the orthorhombic and tetragonal phases. Both $FOM_{on}$ and $FOM_{off}$ have peak values around the phase boundary but the peak compositions are not exactly coincided. The optimal Li fraction in the KNLNT ceramic for a PEH application was found to be between 0.055 and 0.065.