• Title/Summary/Keyword: calculation method

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MMAD Computation for Fast Diamond-Search Algorithm (고속 다이아몬드 탐색 알고리즘을 위한 MMAD 연산법)

  • 서은주;김동우;한재혁;안재형
    • Journal of Korea Multimedia Society
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    • v.4 no.5
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    • pp.406-413
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    • 2001
  • Ordinary high-speed block matching algorithms have a disadvantage that they need to get MAD (Mean Absolute Distance) as many as the number of search points due to comparing the MAD between the current frame's search block and the reference frame's search block. To solve such disadvantage of high-speed block matching algorithm, the proposed high-speed DS algorithm employs a MMAD calculation method using a specific characteristic that neighboring pixels have almost same values. In this thesis, we can get rid of unnecessary MAD calculation between the search point block by the new calculation method which uses the previously calculated MAD as the current search point and by breaking from the established MAD calculation method which calculates the MAD of a new search point by each search stage. Comparing with the established high-speed block matching algorithm, this new calculation's estimated movement error was shown as similar, and th total calculation amount decreased by $2FN^2Ep$.

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Calculation Methods for Slot Utilization Based on Erasure nodes in DQDB Networks (소거노드 기반 DQDB망의 슬롯 이용률 평가식)

  • Cho, Kyoung-Sook;Oh, Bum-Suk;Kim, Chong-Gun
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.10
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    • pp.2654-2662
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    • 1998
  • Maximum single bus throughput of standard IEEE 802.6 DQDB(Distributed Queue Dual Bus) is not obtained over 1. Therefore, lots of studies for improving bus throughput have done by QA slot preuse/reuse. We propose three calculation cethods for network's utilization with preuse/reuse scheme based on erasure nodes. One is calculation method by traffic density function, other is calculation method for obtaining maximum throughput. The other is calculation method using probability concept which follows real DQDB operation mechanisms. The calculated throughputs are compared with each others. The results shows some favorite phenomena. The proposed calculation methods can be casily expanded in mumber of nodes or in number of erasure nodes.

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Developing of Slope Calculation Algorithm using Cell-based Modeling (셀 기반 모델링을 이용한 경사계산 알고리즘 개발)

  • An, Sang-Hyun;Kang, Yong-Seok;Shin, Young-Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.8 no.3
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    • pp.121-128
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    • 2005
  • Forest fire is expanded to large-scale forest fire based on topographic characteristics, particularly slope. This report addresses the currently available methods of calculation slope angle from a digital elevation model and develops a new method that circumvents a number of the shortcomings associated with other algorithms. The results of the comparison of five different slope angle calculation algorithms show that maximum uphill slope angle calculation is the proper method for the purpose of predicting forest fire hazard.

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Computation cost reduction method of EBCOT using upper subband search information in the wavelet domain (웨이블릿 영역에서의 상위 부대역 탐색정보를 이용한 EBCOT의 연산량 감소 방법)

  • Choi, Hyun-Jun;Paik, Yaeung-Min;Seo, Young-Ho;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.8
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    • pp.1497-1504
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    • 2009
  • This Paper Propose a method to reduce the calculation time in JPEG2000. That is, if a coefficient is estimate a upper-level subband and its descendents skip the scan process. There is a trade-off relationship between the calculation time and the image quality or the amount of output data, the calculation time and the amount of output data decreases, but the image degradation increases. The experimental results showed that in calculation time was 35% in average, which means that ls ge ses. The ein calculation time and output data can be obtls ed with a cost of an acceptlble image quality degradation.

Monte Carlo shielding evaluation of a CSNS Multi-Physics instrument

  • Liang, Tairan;Shen, Fei;Yin, Wen;Xu, Juping;Yu, Quanzhi;Liang, Tianjiao
    • Nuclear Engineering and Technology
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    • v.51 no.8
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    • pp.1998-2004
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    • 2019
  • The Multi-Physics (MP) instrument is one of 20 neutron spectrometers planned in the China Spallation Neutron Source (CSNS). This paper presents a shielding calculation for the MP instrument using Monte Carlo codes MCNPX and FLUKA. First, the neutrons that escape from the CSNS decoupled water moderator and are delivered to the beam line of the MP instrument are calculated to use as the source term of the shielding calculation. Then, to validate the calculation method based on multiple variance reduction techniques, a cross check between MCNPX and FLUKA codes is performed by comparing the calculation results of the dose rate distribution on a simplified beam line model. Finally, a complete geometry model of the MP instrument is set up, and the primary parameters for the shielding design are obtained according to the calculated dose rate map considering different worst-case scenarios.

A spent nuclear fuel source term calculation code BESNA with a new modified predictor-corrector scheme

  • Duy Long Ta ;Ser Gi Hong ;Dae Sik Yook
    • Nuclear Engineering and Technology
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    • v.54 no.12
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    • pp.4722-4730
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    • 2022
  • This paper introduces a new point depletion-based source term calculation code named BESNA (Bateman Equation Solver for Nuclear Applications), which is aimed to estimate nuclide inventories and source terms from spent nuclear fuels. The BESNA code employs a new modified CE/CM (Constant Extrapolation - Constant Midpoint) predictor-corrector scheme in depletion calculations for improving computational efficiency. In this modified CE/CM scheme, the decay components leading to the large norm of the depletion matrix are excluded in the corrector, and hence the corrector calculation involves only the reaction components, which can be efficiently solved with the Talyor Expansion Method (TEM). The numerical test shows that the new scheme substantially reduces computing time without loss of accuracy in comparison with the conventional scheme using CRAM (Chebyshev Rational Approximation Method), especially when the substep calculations are applied. The depletion calculation and source term estimation capability of BESNA are verified and validated through several problems, where results from BESNA are compared with those calculated by other codes as well as measured data. The analysis results show the computational efficiency of the new modified scheme and the reliability of BESNA in both isotopic predictions and source term estimations.

A dynamic finite element method for the estimation of cable tension

  • Huang, Yonghui;Gan, Quan;Huang, Shiping;Wang, Ronghui
    • Structural Engineering and Mechanics
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    • v.68 no.4
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    • pp.399-408
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    • 2018
  • Cable supported structures have been widely used in civil engineering. Cable tension estimation has great importance in cable supported structures' analysis, ranging from design to construction and from inspection to maintenance. Even though the Bernoulli-Euler beam element is commonly used in the traditional finite element method for calculation of frequency and cable tension estimation, many elements must be meshed to achieve accurate results, leading to expensive computation. To improve the accuracy and efficiency, a dynamic finite element method for estimation of cable tension is proposed. In this method, following the dynamic stiffness matrix method, frequency-dependent shape functions are adopted to derive the stiffness and mass matrices of an exact beam element that can be used for natural frequency calculation and cable tension estimation. An iterative algorithm is used for the exact beam element to determine both the exact natural frequencies and the cable tension. Illustrative examples show that, compared with the cable tension estimation method using the conventional beam element, the proposed method has a distinct advantage regarding the accuracy and the computational time.

Reliability Assessment and Transmission Capability Calculation in Power System using Well-being Method (Well-being 평가기법을 이용한 전력시스템의 신뢰도평가 및 송전용량 계산)

  • Son, Hyun-Il;Bae, In-Su;Kim, Jin-O
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.5
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    • pp.841-846
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    • 2010
  • Reliability in electrical power system refers to normal operation for schedule time in some system that action consists. It means that if there is no contingency of electric power supply decrease or load curtailment, reliability of the system is high. In this paper, a method for evaluation of transmission capability is proposed considering reliability standards. Deterministic and probabilistic methods for evaluation of transmission capability has been studied. These researches considered uncertainty of system components or N-1 contingency only. However, the proposed method can inform customers and system operators more suitable transmission capability. Well-being method using state probabilities of system components proves to be a more effective method in this paper comparing with calculation of LOLE(Loss of Load Expectation). The length of calculation is shorter but it can give more practical information to the exact system operators. Well-being method is applied to IEEE-RTS 24bus system to evaluate reliability in case study. The result is compared with a existing way to evaluate reliability with LOLE and it shows that transmission capability connected with adjacent networks. This paper informs system operators and power suppliers of reliable information for operating power system.

Mesurement of Evoked Otoacoustic Emission Latency Using Linear Prediction Coding Spectrum (선형예측부호화 스펙트럼을 이용한 유발이음청 방재파의 잠시측정)

  • An, Jung-Il;Choi, Jin-Young;Lee, Kuhn-Il
    • Journal of Biomedical Engineering Research
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    • v.12 no.3
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    • pp.185-190
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    • 1991
  • An automatized latency calculation method of an e-OAE(evoked otacoustic emission) is proposed. The e-OAE signal measured from a normal adult is averaged 1000 times to remove noises. This averaged signal is converted to digital signal and that is processed by IBM-AT computer for latency calculation. we separate the stimulated and the emitted signal on the time domain by a modified LPC (linear prediction coding) spectrum, and the latency is calculated by cross-correlation method. By proposed latency calculation method the latency is 7.9[ms] for normal adult. The performance of the proposed method is also compared with that of the auto-correlation and cross performance of the proposed method is also compared with that of the auto-correlation and cross-correlation method. The result show that the proposed method has same precision with the conventional methods and can automatically calculate latency without subjective observation.

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A Novel Rotor Position Error Calculation Method using a Rotation Matrix for a Switching Frequency Signal Injected Sensorless Control in IPMSM (스위칭 주파수 신호 주입 IPMSM 센서리스 제어를 위한 회전 행렬 기반의 새로운 위치 오차 추정 기법)

  • Kim, Sang-Il;Kim, Rae-Young
    • The Transactions of the Korean Institute of Power Electronics
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    • v.20 no.5
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    • pp.402-409
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    • 2015
  • This paper proposes a novel rotor position error calculation method for high-frequency signal-injected sensorless control. The rotor position error using the conventional modulation method can be only measured up to ${\pm}45^{\circ}$. In addition, when the rotor position estimation error is not sufficiently small, the small angle approximation in no longer valid. To overcome these problems, this study introduces a new rotor position error calculation method using the rotating matrix. In this study, the position error measurement range of the proposed method is extended from ${\pm}45^{\circ}$ to ${\pm}90^{\circ}$. The linearity between the real rotor position error and the estimated error is maintained by nearly $90^{\circ}$. These features of the proposed method improve the performance of the sensorless control. The validity of the proposed method is verified by simulations and experiments.