• Title/Summary/Keyword: scaling methods

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Low Back Pain and Related factors in Dental Hygienists (일부 치과위생사의 요통경험 및 관련요인(II))

  • Yi Seung-Ju;Cho Myung-Sook
    • The Journal of Korean Physical Therapy
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    • v.11 no.2
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    • pp.123-130
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    • 1999
  • Objectives : This study was to investigate the experience rate and factors related with Low Back Pain(LBP). Methods : Questionnaires were completed by 236 dental hygienists in Taegu city and Kyungpook province in June 23-27, 1999. The solicited information was used to estimate odds ration and $95\%$ confidence intervals for the LBP related factors association. Results : The experience rate of LBP was $78\%$. The experience rate of LBP was significantly associated with scaling posture(odds ratio=2.228)(p=0.0371) and stress with dentist(odds ratio=2.767) (p=0.0136). Conclusions : Data from this study support a statistically significant association between LBP and some factors found in other research to increase the relation with LBP. Study findings may have implications for targeting at dental hygienists for scaling posture education or intervention program.

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Robust Blind Watermarking using DCT Texture Block Coefficient (DCT 질감 블록 계수를 이용한 강인한 블라인드 워터마킹)

  • Shin, Yong-Dal;Park, Kyung-Nam
    • Journal of Korea Society of Industrial Information Systems
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    • v.13 no.4
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    • pp.108-114
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    • 2008
  • In this paper, we proposed robust blind watermarking algorithm using texture block coefficient based on discrete cosine transform(DCT). The proposed method embedded all of watermark signals into DC component of $8\times8$ block DCT in order to robust various external attack The texture block coefficient was composed absolute value of DCT coefficients. Experiment showed that the proposed method better than conventional methods in the invisibility and various attack such as dithering, cropping, and scaling.

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Blind Watermarking Using DCT and Variance (DCT 및 분산을 이용한 블라인드 워터마킹)

  • Shin, Yong-Dal
    • Journal of Korea Multimedia Society
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    • v.9 no.10
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    • pp.1276-1281
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    • 2006
  • In this paper, We proposed a robust blind digital watermarking algorithm using variance and DCT domain. The proposed method embedded watermark signals into DC components of $8{\times}8$ block DCT using valiance, texture regions and smooth regions. In the digital watermarking algorithms using DCT domain, more robustness can be achieved if watermarks are embedded in DC components since DC components have much larger perceptual capacity than AC components. Experiment showed that robustness of the proposed method better than that of the conventional methods in JPEG quality and scaling attack.

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A TWO-LEVEL FINITE ELEMENT METHOD FOR THE STEADY-STATE NAVIER-STOKES/DARCY MODEL

  • Fang, Jilin;Huang, Pengzhan;Qin, Yi
    • Journal of the Korean Mathematical Society
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    • v.57 no.4
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    • pp.915-933
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    • 2020
  • A two-level finite element method based on the Newton iterative method is proposed for solving the Navier-Stokes/Darcy model. The algorithm solves a nonlinear system on a coarse mesh H and two linearized problems of different loads on a fine mesh h = O(H4-𝜖). Compared with the common two-grid finite element methods for the considered problem, the presented two-level method allows for larger scaling between the coarse and fine meshes. Moreover, we prove the stability and convergence of the considered two-level method. Finally, we provide numerical experiment to exhibit the effectiveness of the presented method.

Neural Network based Fuzzy Type PID Controller Design (신경 회로망 기반 퍼지형 PID 제어기 설계)

  • 임정흠;권정진;이창구
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.86-86
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    • 2000
  • This paper describes a neural network based fuzzy type PID control scheme. The PID controller is being widely used in industrial applications. however, it is difficult to determine the appropriate PID gains for (he nonlinear system control. In this paper, we re-analyzed the fuzzy controller as conventional PID controller structure, and proposed a neural network based fuzzy type PID controller whose scaling factors were adjusted automatically. The value of initial scaling factors of the proposed controller were determined on the basis of the conventional PID controller parameters tuning methods and then they were adjusted by using neural network control techniques. Proposed controller was simple in structure and computational burden was small so that on-line adaptation was easy to apply to. The result of practical experiment on the magnetic levitation system, which is known to be hard nonlinear, showed the proposed controller's excellent performance.

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A Study on Clustering Kansei Factors for the Surface Roughness of Materials

  • Jun, Chang Lim;Choi, Kyungmee
    • Communications for Statistical Applications and Methods
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    • v.10 no.1
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    • pp.49-60
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    • 2003
  • The human sensibility product design requires information on consumer's emotions such as vision, auditory, olfactory, gustatory, or tactile perceptions. In this study, tactile sense which has not been well studied compared to other senses, is measured and statistically analysed. The emotional responses of 37 pairs of positive and negative adjectives describing tactile senses are collected and analysed through the questionnaire to find the correlation between adjectives and surface roughness of the sample. Mean ranks for 37 pairs of adjectives on four samples are obtained, and used to cluster these adjectives by factor analysis, multidimensional scaling, or cluster analysis.

Hybrid Fuzzy Controller Based on Control Parameter Estimation Mode Using Genetic Algorithms (유전자 알고리즘을 이용한 제어파라미터 추정모드기반 HFC)

  • Lee, Dae-Keun;Oh, Sung-Kwun;Jang, Sung-Whan
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2545-2547
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    • 2000
  • In this paper, a hybrid fuzzy controller using genetic algorithm based on parameter estimation mode to obtain optimal control parameter is presented. First, The control input for the system in the HFC is a convex combination of the FLC's output in transient state and PID's output in steady state by a fuzzy variable, namely, membership function of weighting coefficient. Second, genetic algorithms is presented to automatically improve the performance of hybrid fuzzy controller utilizing the conventional methods for finding PID parameters and estimation mode of scaling factor. The algorithms estimates automatically the optimal values of scaling factors, PID parameters and membership function parameters of fuzzy control rules according to the rate of change and limitation condition of control input. Computer simulations are conducted to evaluate the performance of proposed hybrid fuzzy controller. ITAE, overshoot and rising time are used as a performance index of controller.

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A study about rotor position estimation enhance using IQ math in DSP (DSP 내의 IQ math를 이용한 회전자 위치 추정 정밀도 향상에 관한 연구)

  • Jang, Joong-Hack;Lee, Kwang-Ho;Hong, Sun-Ki
    • Proceedings of the KIEE Conference
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    • 2005.10c
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    • pp.98-100
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    • 2005
  • DSPs used at motor control are usually fixed point processor. They need scaling because they cannot excute floating point calculation. Scaling for floating point calculation makes the DSP's speed down, complex coding and etc. Therefore the IQ math is adopted. IQ math makes the fixed point processor possible to calculate the floating point math. In addition, IQ math can reduce memory usage and be more faster than that without IQ math. It seems that IQ math is appropriate in motor position control. In comparison of the position calculation between the IQ math, math function and the sine table, the method using IQ math is superior than other methods.

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A MONTE CARLO METHOD FOR SOLVING HEAT CONDUCTION PROBLEMS WITH COMPLICATED GEOMETRY

  • Shentu, Jun;Yun, Sung-Hwan;Cho, Nam-Zin
    • Nuclear Engineering and Technology
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    • v.39 no.3
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    • pp.207-214
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    • 2007
  • A new Monte Carlo method for solving heat conduction problems is developed in this study. Differing from other Monte Carlo methods, it is a transport approximation to the heat diffusion process. The method is meshless and thus can treat problems with complicated geometry easily. To minimize the boundary effect, a scaling factor is introduced and its effect is analyzed. A set of problems, particularly the heat transfer in the fuel sphere of PBMR, is calculated by this method and the solutions are compared with those of an analytical approach.

Face Size Detection using Deep Learning (딥 러닝을 통한 얼굴 크기 탐지)

  • Tseden, Batkhongor;Lee, Hae-Yeoun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2018.05a
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    • pp.352-353
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    • 2018
  • Many deep learning approaches are studied for face detection in these days. However, there is still a performance problem to run efficiently on devices with limited resources. Our method can enhance the detection speed by decreasing the number of scaling for detection methods that use many different scaling per image to detect the different size of faces. Also, we keep our deep learning model easy to implement and small as possible. Moreover, it can be used for other special object detection problems but not only for face detection.