• Title/Summary/Keyword: scaling factor

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Evaluation of the Dynamic P-Y Curves of Soil-Pile System in Liquefiable Ground (액상화 가능성이 있는 지반에 놓인 지반-말뚝 시스템의 동적 p-y 곡선 연구)

  • Han, Jin-Tae;Kim, Sung-Ryul;Kim, Myoung-Mo
    • Journal of the Korean Geotechnical Society
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    • v.23 no.3
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    • pp.141-147
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    • 2007
  • Various approaches have been developed for the dynamic response analysis of piles. In one of the approaches, the soil-pile interaction is approximated by using parallel nonlinear springs, namely the p-y curves. Currently available p-y curve recommendations are based on static and cyclic lateral load tests. Other researchers have attempted to extend the p-y curves by incorporating the effects of liquefaction on soil-pile interaction and derived scaling factors of p-y curves to account fur the liquefaction. However, opinions on the scaling factors vary. In this study, the sealing factors, which reflect the variation of the elastic moduli of surrounding soils, were established combining the relationship between excess pore pressures and the natural frequencies of a soil-pile system obtained from Ig shaking table tests and the relationship between the elastic moduli of surrounding soils and the natural frequencies of a soil-pile system obtained from numerical analyses. As a result, the scaling factors were presented in an exponential function.

Scaling Factor Tuning Method for Fuzzy Control System (퍼지제어 시스템을 위한 이득동조 방법)

  • 최한수;김성중
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.43 no.5
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    • pp.819-826
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    • 1994
  • This paper deals with a self-tuning fuzzy controller. The fuzzy controller is constructed with linguistic rules which consist of the fuzzy sets. Each fuzzy set is characterized by a membership function. The tuning fuzzy controller has paramenters that are input/output scaling factors to effect control output. In this paper we propose a tuning method for the scaling factor Computer simulations carried out on first-order and second-order processes will show how the present tuning approach improves the transient and the steady-state characteristics of the overall system.The applicability of the proposed algorithm is certified by computer simulation results.

A Study on the Impedance Scaled Tele-Nanomanipulation in a Nanoscale Virtual Environment (나노 스케일 가상환경에서의 나노-원격 조작의 임피던스 스케일링에 관한 연구)

  • Kim, Sung-Gaun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.11 s.254
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    • pp.1401-1407
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    • 2006
  • In a haptic interface system with a nanoscale virtual environment (NVE) using an atomic force microscope (AFM), impedance scaling is important. In order to explicitly derive the relationship between performance and impedance scaling factors, a nanoscale virtual coupling (NSVC) concept and a selection method of scaling factors of velocity (or position) and force are introduced. An available scaling factor region is represented based on Llewellyn's absolute stability criteria and the physical limitation of the haptic device. Experiments have been performed for tele-nanomanipulation tasks such as positioning, indenting and nanolithography with available force scaling factor in the NVE.

Control of Electromagnetic Levitation System using ε-scaling Partial State Feedback Controller (ε조절 요소를 가진 부분 상태 궤환 제어기를 이용한 자기부상 시스템의 제어)

  • Park, Gyu-Man;Choi, Ho-Lim
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.8
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    • pp.1572-1576
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    • 2011
  • The electromagnetic levitation(EMS) system is one of the well-known nonlinear system because of its nonlinearity and several control techniques have been proposed. We propose an ${\epsilon}$-scaling partial feedback controller for the ball position control of the EMS system. The key feature of our proposed controller is the use of the scaling factor ${\epsilon}$ which provides a function of controller gain tuning along with robustness. In this paper, we show the stability analysis of our proposed controller and the convergence analysis of the state observer in terms of ${\epsilon}$-scaling factor. In addition, the experimental results show the validity of the proposed controller and improved control performance over the conventional PID controller.

A New Scaling Theory for the Effective Conducting Path Effect of Dual Material Surrounding Gate Nanoscale MOSFETs

  • Balamurugan, N.B.;Sankaranarayanan, K.;Suguna, M.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.8 no.1
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    • pp.92-97
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    • 2008
  • In this Paper, we present a scaling theory for dual material surrounding gate (DMSGTs) MOSFETs, which gives a guidance for the device design and maintaining a precise subthreshold factor for given device parameters. By studying the subthreshold conducting phenomenon of DMSGTs, the effective conductive path effect (ECPE) is employed to acquire the natural length to guide the design. With ECPE, the minimum channel potential is used to monitor the subthreshold behavior. The effect of ECPE on scaling factor significantly improves the subthreshold swing compared to conventional scaling rule. This proposed model offers the basic designing guidance for dual material surrounding gate MOSFETs.

Performance and Convergence Analysis of Tree-LDPC codes on the Min-Sum Iterative Decoding Algorithm (Min-Sum 반복 복호 알고리즘을 사용한 Tree-LDPC의 성능과 수렴 분석)

  • Noh Kwang-seok;Heo Jun;Chung Kyuhyuk
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.1C
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    • pp.20-25
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    • 2006
  • In this paper, the performance of Tree-LDPC code is presented based on the min-sum algorithm with scaling and the asymptotic performance in the water fall region is shown by density evolution. We presents that the Tree-LDPC code show a significant performance gain by scaling with the optimal scaling factor which is obtained by density evolution methods. We also show that the performance of min-sum with scaling is as good as the performance of sum-product while the decoding complexity of min-sum algorithm is much lower than that of sum-product algorithm. The Tree-LDPC decoder is implemented on a FPGA chip with a small interleaver size.

An Adaptive Maximum Power Point Tracking Scheme Based on a Variable Scaling Factor for Photovoltaic Systems (태양광 시스템을 위한 가변 조정계수 기반의 적응형 MPPT 제어 기법)

  • Lee, Kui-Jun;Kim, Rae-Young;Hyun, Dong-Seok;Lim, Chun-Ho;Kim, Woo-Chull
    • The Transactions of the Korean Institute of Power Electronics
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    • v.17 no.5
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    • pp.423-430
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    • 2012
  • An adaptive maximum power point tracking (MPPT) scheme employing a variable scaling factor is presented. A MPPT control loop was constructed analytically and the magnitude variation in the MPPT loop gain according to the operating point of the PV array was identified due to the nonlinear characteristics of the PV array output. To make the crossover frequency of the MPPT loop gain consistent, the variable scaling factor was determined using an approximate curve-fitted polynomial equation about linear expression of the error. Therefore, a desirable dynamic response and the stability of the MPPT scheme were maintained across the entire MPPT voltage range. The simulation and experimental results obtained from a 3 KW rated prototype demonstrated the effectiveness of the proposed MPPT scheme.

An Effective Viewport Resolution Scaling Technique to Reduce the Power Consumption in Mobile GPUs

  • Hwang, Imjae;Kwon, Hyuck-Joo;Chang, Ji-Hye;Lim, Yeongkyu;Kim, Cheong Ghil;Park, Woo-Chan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.8
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    • pp.3918-3934
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    • 2017
  • This paper presents a viewport resolution scaling technique to reduce power consumption in mobile graphic processing units (GPUs). This technique controls the rendering resolution of applications in proportion to the resolution factor. In the mobile environment, it is essential to find an effective resolution factor to achieve low power consumption because both the resolution and power consumption of a GPU are in mutual trade-off. This paper presents a resolution factor that can minimize image quality degradation and gain power reduction. For this purpose, software and hardware viewport resolution scaling techniques are applied in the Android environment. Then, the correlation between image quality and power consumption is analyzed according to the resolution factor by conducting a benchmark analysis in the real commercial environment. Experimental results show that the power consumption decreased by 36.96% on average by the hardware viewport resolution scaling technique.

Relation of Threshold Voltage and Scaling Theory for Double Gate MOSFET (DGMOSFET의 문턱전압과 스켈링 이론의 관계)

  • Jung, Hak-Kee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.5
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    • pp.982-988
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    • 2012
  • This paper has presented the relation of scaling theory and threshold voltage of double gate(DG) MOSFET. In the case of conventional MOSFET, current and switching frequency have been analyzed based on scaling theory. To observe the possibility of application of scaling theory for threshold voltage of DGMOSFET, the change of threshold voltage has been observed and analyzed according to scaling theory. The analytical potential distribution of Poisson equation has been used, and this model has been already verified. To solve Poisson equation, charge distribution such as Gaussian function has been used. As a result, it has been observed that threshold voltage is grealty changed according to scaling factor and change rate of threshold voltages is traced for scaling of doping concentration in channel. This paper has explained for the best modified scaling theory reflected the influence of two gates as using weighting factor when scaling theory has been applied for channel length and channel thickness.

The effects of scaling factors and quantization in sensors on free motion of teleoperation system

  • Hwang, Dal-Yeon;Cho, SangKyu;Park, Sanguk
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1512-1515
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    • 1997
  • One of the advantages of master-slave teleoperation is scaling concept such as position scaling, force scaling Meanuhile, lots of quantization effects are generated from position and force sensors in the master and slave manipulator. In this paper, to show the output error caused by the quantizaion effects from the position sensor and position scaling factor, simulation is done for free motion without contact in slave side. Transfer functiion model in which the quantization effect is assumed to be a disturbance input to the system is derived. Model shows that Jacobian, scaling factors, and controller affect the output by quantization effects form esnsors. One dof master and slave are used for simulation. In our study, the higher sensor resolution decreases the output error form quantization. Scaling factors can amplify the quantizatiion effects form the sensors in master and slave manipulators.

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