• Title/Summary/Keyword: Simplified computation method

Search Result 81, Processing Time 0.021 seconds

The facial expression generation of vector graphic character using the simplified principle component vector (간소화된 주성분 벡터를 이용한 벡터 그래픽 캐릭터의 얼굴표정 생성)

  • Park, Tae-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.12 no.9
    • /
    • pp.1547-1553
    • /
    • 2008
  • This paper presents a method that generates various facial expressions of vector graphic character by using the simplified principle component vector. First, we analyze principle components to the nine facial expression(astonished, delighted, etc.) redefined based on Russell's internal emotion state. From this, we find principle component vector having the biggest effect on the character's facial feature and expression and generate the facial expression by using that. Also we create natural intermediate characters and expressions by interpolating weighting values to character's feature and expression. We can save memory space considerably, and create intermediate expressions with a small computation. Hence the performance of character generation system can be considerably improved in web, mobile service and game that real time control is required.

A Comparative Study of Branch Metric Calculator in QAM-TCM Decoder (QAM-TCM 복호기의 가지척도계산방식 비교 연구)

  • 김진우;최시연;강병희;오길남;김덕현
    • Proceedings of the IEEK Conference
    • /
    • 2001.09a
    • /
    • pp.249-252
    • /
    • 2001
  • TCM(Trellis Coded Modulation) has soft decision scheme so that BM(Branch Metric) calculates the ED(Euclidean Distance) between the received signal and each code words in signal space. For computing the ED, square and square root computations increase the hardware complexity. Some simplified method is known for convolutional codes with QPSK(Quadrature Phase Shift Keying), PSK(Phase Shift Keying) modulation. But it is not acceptable for QAM (Quadrature Amplitude Modulation)-TCM scheme. In this paper, we suggest that two modified BM computation methods, which is applicable for QAM-TCM. By comparative study, we also assessed two proposed method in the case of hardware complexity and BER (Bit Error Rate) performance.

  • PDF

A STUDY ON THERMAL MODEL REDUCTION ALGORITHM FOR SATELLITE PANEL (인공위성 패널 열해석모델 간소화 알고리즘 연구)

  • Kim, Jung-Hoon;Jun, Hyoung Yoll;Kim, Seung Jo
    • Journal of computational fluids engineering
    • /
    • v.17 no.4
    • /
    • pp.9-15
    • /
    • 2012
  • Thermal model reduction algorithms and techniques are introduced to condense a huge satellite panel thermal model into the simplified model on the purpose of calculating the thermal responses of a satellite on orbit. Guyan condensation algorithm with the substitution matrix manipulation is developed and the mathematical procedure is depicted step by step. A block-form LU decomposition method is also invited to compare the developed algorithm. The constructed reduced thermal model induced from the detailed model based on a real satellite panel is satisfying the correlation criterion of ${\pm}2^{\circ}C$ for the validity accuracy. Guyan condensation algorithm is superior to the block-form LU decomposition method on computation time.

Assessment of speckle image through particle size and image sharpness

  • Qian, Boxing;Liang, Jin;Gong, Chunyuan
    • Smart Structures and Systems
    • /
    • v.24 no.5
    • /
    • pp.659-668
    • /
    • 2019
  • In digital image correlation, speckle image is closely related to the measurement accuracy. A practical global evaluation criterion for speckle image is presented. Firstly, based on the essential factors of the texture image, both the average particle size and image sharpness are used for the assessment of speckle image. The former is calculated by a simplified auto-covariance function and Gaussian fitting, and the latter by focusing function. Secondly, the computation of the average particle size and image sharpness is verified by numerical simulation. The influence of these two evaluation parameters on mean deviation and standard deviation is discussed. Then, a physical model from speckle projection to image acquisition is established. The two evaluation parameters can be mapped to the physical devices, which demonstrate that the proposed evaluation method is reasonable. Finally, the engineering application of the evaluation method is pointed out.

Practical formula for determining peak acceleration of footbridge under walking considering human-structure interaction

  • Cao, Liang;Zhou, Hailei;Chen, Y. Frank
    • Structural Engineering and Mechanics
    • /
    • v.83 no.6
    • /
    • pp.729-744
    • /
    • 2022
  • In this paper, an analytical formulation is proposed to predict the vertical vibration response due to the pedestrian walking on a footbridge considering the human-structure interaction, where the footbridge and pedestrian are represented by the Euler beam and linear oscillator model, respectively. The derived coupled equation of motion is a nonlinear fourth-order partial differential equation. An uncoupled solution strategy based on the combined weighted residual and perturbation method) is proposed to reduce the tedious computation, which allows the separate integration between the bridge and pedestrian subsystems. The theoretical study demonstrates that the pedestrian subsystem can be treated as a structural system with added mass, damping, and stiffness. The analysis procedure is then applied to a case study under the conditions of single pedestrian and multi pedestrians, and the results are validated and compared numerically. For convenient vibration design of a footbridge, the simplified peak acceleration formula and the idea of decoupling problem are thus proposed.

Simplified approach for symbol error rate analysis of SC-FDMA scheme over Rayleigh fading channel

  • Trivedi, Vinay Kumar;Sinha, Madhusudan Kumar;Kumar, Preetam
    • ETRI Journal
    • /
    • v.40 no.4
    • /
    • pp.537-545
    • /
    • 2018
  • In this paper, we present a comprehensive analytical study of the symbol error rate (SER) of single-carrier frequency-division multiple access (SC-FDMA) with zero-forcing frequency domain equalization (ZF-FDE) over a Rayleigh fading channel. SC-FDMA is considered as a potential waveform candidate for fifth-generation (5G) radio access networks (RANs). First, the $N_C$ fold convolution of the noise distribution of an orthogonal frequency-division multiplexing (OFDM) system is computed for each value of the signal-to-noise ratio (SNR) in order to determine the noise distribution of the SC-FDMA system. $N_C$ is the number of subcarriers assigned to a user or the size of the discrete Fourier transform (DFT) precoding. Here, we present a simple alternative method of calculating the SER by simplifying the $N_C$ fold convolution using time and amplitude scaling properties. The effects of the $N_C$ fold convolution and SNR over the computation of the SER of the SC-FDMA system has been separated out. As a result, the proposed approach only requires the computation of the $N_C$ fold convolution once, and it is used for different values of SNR to calculate the SER of SC-FDMA systems.

An analysis of Flood Inundation using Query and Mathematical Method (Query 및 Mathematical 기법을 이용한 홍수범람 해석)

  • Jeong, Ha-Ok;Park, Sang-Woo;Choo, Tai-Ho;Park, Kun-Chul
    • Journal of Wetlands Research
    • /
    • v.12 no.1
    • /
    • pp.33-40
    • /
    • 2010
  • In this study, it has been intended to present the ways to improve some problems such as the difficulty of using the program which had got from the existing study, the computation and application of a lot of parameter and the complicated processing which need to be more simplified. Also It has been tried to bring up the ways to make a flood inundation map and a detailed inundation analysis which could reduce the risk factors. We selected an Anseong-Cheon basin, and wrote a flood inundation scenario based on extreme flood to exceed the planned frequency to consider only overflow and levee break and executed inundation simulation. Researchers conducted an analysis of overflow and levee break using function of HEC-RAS Storage with a One-Dimensional model. It applied Elevation versus Volume Curve for more correct inundation simulation than a method of Area-Time-Depth which used in popular. This study will suggest a mathematical method of SURFER with a little difference of inundation area more simplified and precise flood inundation than complicated Arcview 3.2a which used Query method of Arcview 3.2a.

A response spectrum method for seismic response analysis of structures under multi-support excitations

  • Li, Jian-Hua;Li, Jie
    • Structural Engineering and Mechanics
    • /
    • v.21 no.3
    • /
    • pp.255-273
    • /
    • 2005
  • Based on the random vibration theory, a response spectrum method is developed for seismic response analysis of linear, multi-degree-of-freedom structures under multi-support excitations is developed. Various response quantities, including the mean and variance of the peak response, the response mean frequency, are obtained from proposed combination rules in terms of the mean response spectrum. This method makes it possible to apply the response spectrum to the seismic reliability analysis of structures subjected to multi-support excitations. Considering that the tedious numerical integration is required to compute the spectral parameters and correlation coefficients in above combination rules, this paper further offers simplified procedures for their computation, which enhance dramatically the computational efficiency of the suggested method. The proposed procedure is demonstrated for tow numerical examples: (1) two-span continuous beam; (2) two-tower cabled-stayed bridge by using Monte Carlo simulation (MC). For this purpose, this paper also presents an approach to simulation of ground motions, which can take into account both mean and variation properties of response spectrum. Computed results based on the response spectrum method are in good agreement with Monte Carlo simulation results. And compared with the MSRS method, a well-developed multi-support response spectrum method, the proposed method has an incomparable computational efficiency.

A Study of Error Estimation and Adaptive Junction Subdivision for Electromagnetic Topology (전자기 토폴러지 기법에서의 오차 추정 및 적응적 정션 세분화 연구)

  • Park, Yoon-Mi;Chung, Young-Seek;Jung, Hyun-Kyo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.24 no.6
    • /
    • pp.623-632
    • /
    • 2013
  • Electromagnetic topology simplifies a complex analysis area in accordance with electromagnetic coupling. And then electromagnetic topology divides the simplified continuous area into sub-areas and analyzes electromagnetic problems at the sub-areas. Therefore electromagnetic topology has a merit to analyze the electromagnetic coupling in large and complex systems, however simplified modeling technique can generate large errors. In this paper, power balance method is used to estimate errors and subdivide junctions in the electromagnetic topology. The method is applied to analyze conducted and radiated electromagnetic coupling in two kinds of cavity models. Improvement of accuracy was accomplished in accordance with junction subdivision. Moreover we could save computation time and memory comparing with FDTD results.

Simplified projective transform for reconstruction of cylindrical panorama (실린더 파노라마 영상의 재구성을 위한 단순화된 사영 변환)

  • Lee Kang-Ho
    • Journal of the Korea Society of Computer and Information
    • /
    • v.11 no.2 s.40
    • /
    • pp.169-175
    • /
    • 2006
  • In this paper we propose a method of reconstruction of cylindrical panorama using simplified projective transform from the panning image on the fixed camera. For the practical construction of cylindrical panorama we consider the rotation of the camera on the Y-axis only, even though considering the rotation components on all of the X,Y,Z axis on three-dimensional space for projective transform between general panoramas. The restriction mentioned above simplifies projective transform with existing 8 degrees of freedom into the one with 4 degrees of freedom. In the results, overall computation for projective transform can be decreased to the great extents in quantify, because the number of corresponding points required for inducing the transforming formula is gone down by half. Proposed algorithm from the simulation carried out in this paper shows similar performance and decreased computational quantity compared with existing algorithm. Also, it shows the construction of cylindrical panorama using simplified projective transform.

  • PDF