• 천문학회보
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• 제41권2호
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• pp.58.3-58.3
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• 2016

The Kepler space mission provides quantitative and qualitative photometric time series of oscillating stars. It is possible to examine statistical study with seismic properties of solar-like stars. Global seismic properties - large frequency separation (${\Delta}{\nu}$), frequency of maximum power (${\nu}_{max}$) and amplitude of Gaussian envelope (A) widely have been used to determine empirical scaling relations for inferring the stellar physical quantities - mass, age and temperature. We aim to confirm whether width of Gaussian envelope on power excess (${\delta}{\nu}_{env}$) can be used with parameter of scaling relation before redgiant phase using Kepler data. Therefore we analyze the characteristics of ${\delta}{\nu}_{env}$ of 129 solar-like stars from main-sequence to subgiant. We have demonstrated that ${\delta}{\nu}_{env}$ has highly correlations with global parameters - ${\Delta}{\nu}$ and ${\nu}max$. We have also found the break of ${\delta}{\nu}_{env}-{\Delta}{\nu}$ and ${\nu}_{max}$ relations.

• 전자공학회논문지
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• 제49권12호
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• pp.173-178
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• 2012

RF 직접 추출 방법을 통해 얻은 정확한 MOSFET 기판 파라미터를 이용하여 기판저항만을 가진 BSIM4 모델은 스케일링 부정확성 때문에 넓은 영역의 게이트 길이에 적용하기에는 물리적으로 맞지 않다는 것이 증명됐다. BSIM4의 비물리적인 문제점을 제거하기 위해서 추가적인 유전체 기판 캐패시터를 가진 수정된 BSIM4 모델이 사용되었고, 이 모델의 물리적 타당성은 우수한 게이트 길이 scalability를 관찰함으로써 증명되었다.

• Korea-Australia Rheology Journal
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• 제13권4호
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• pp.197-203
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• 2001

We reported on the eletrorheological (ER) properties of several semiconducting polymers including poly (p-phenylene) (PPP), poly (acene quinone) radicals (PAQRs), microencapsulated polyaniline (MPANI) and polyaniline (PANI) those we synthesized. The yield stress dependence on electric field strength for the ER fluids using these semiconducting polymers was mainly examined. The yield stress, which is an important design parameter for ER fluids, was observed to satisfy a universal scaling function, allowing that yield stress data for all the ER fluids examined in this study collapse onto a single curve for a broad range of electric field strengths. The proposed scaling function incorporates both the polarization and conductivity models.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2000년도 춘계학술대회 학술발표 논문집
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• pp.228-231
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• 2000

A hybrid fuzzy controller by means of the genetic algorithms is presented. The control input for the system in the HFC is a convex combination of the FLC's output in transient state and PlD's output in steady state by a fuzzy variable. The HFC combined a PID controller with a fuzzy controller concurrently produces the better output performance than any other controller. A auto-tuning algorithms is presented to automatically improve the performance of hybrid fuzzy controller using genetic algorithms. The algorithms estimates automatical Iy the optimal values of scaling factors, PID parameters and membership function parameters of fuzzy control rules. Especially, in order to auto-tune scaling factors and PID parameters of HFC using GA three kinds of estimation modes are effectively utilized. The HFCs are applied to the second process with time-delay. Computer simulations are conducted at step input and the performances of systems are evaluated and also discussed in ITAE(Integral of the Time multiplied by the Absolute value of Error ) and other ways.

• 전기전자학회논문지
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• 제27권4호
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• pp.391-398
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• 2023

In this paper, we propose an alternative analysis to regulate DC motors using a PID controller with a gain scaling factor. We start by providing a systematic design method for selecting the PID gains of our proposed controller by seeing the effect of ϵ on damping ratio, overshoot and settling time from the frequency response analysis. With the help of matlab (simulink), We proceed to show that the proposed controller provides robust stability against system parameter uncertainty and the effect of the gain scaling factor on steady-state error. The validity of our control method along with the analysis is verified with the simulation results.

• Advances in concrete construction
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• 제13권6호
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• pp.471-479
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• 2022

In this paper, vibrational attributes of double-walled carbon nanotubes (CNTs) has been studied based upon nonlocal elastic shell theory. The implication of small scale is being perceived by establishing nonlocal Love shell model. The wave propagation approach has been operated to frame the governing equations as eigen value system. The comparison of local and nonlocal model has been overtly explored by means of scaling parameter. An appropriate selection of material properties and nonlocal parameter has been considered. The influence of changing mechanical parameter Young's modulus has been studied in detail. The dominance of end condition via nonlocal parameter is explained graphically. The results generated furnish the evidence regarding applicability of nonlocal shell model and also verified by earlier published literature.

• Journal of Advanced Marine Engineering and Technology
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• 제34권1호
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• pp.109-115
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• 2010

본 논문은 퍼지 제어를 통한 이동용 로봇에 대한 추적 제어에 대해서 다루고 있다. 이동용 로봇은 Mamdani 형식의 퍼지 제어기로 제어 된다. 퍼지 제어기에 있어서 이동용 로봇과 목표 사이의 각도와 각도의 변화율이 입력으로 사용되고, 출력으로 조향각이 추론되어 제어입력이 된다. 퍼지 규칙은 전문가의 경험적 지식을 참조하여 7개를 사용하였다. 또한 퍼지 제어기 설계에 있어서 하나의 관심 분야인 환산계수(scaling factor) 조정 방법에 대해 제안한다. 본 논문에서는 이를 위해 파라미터 최적화 분야에서 잘 알려진 실수코딩 유전알고리즘을 적용하였다. 시뮬레이션을 통해 다양한 초기 조향각이 주어진 경우, 목표치에 대한 추적 안정성을 보여 퍼지 제어기의 유효성이 확인된다.

• 한국정보통신학회논문지
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• 제18권2호
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• pp.303-310
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• 2014

n개의 무선 노드가 랜덤하게 위치한 초 광 대역 애드 혹 네트워크에서의 개선된 용량 스케일링 법칙을 보인다. 먼저, 수정된 계층적 협력 기술이 사용되는 경우를 고려한다. 단위 면적의 밀집 네트워크에서, 유도한 용량 스케일링은 전력 제한된 성격 때문에 특정 동작 영역에서 경로손실 지수 ${\alpha}$에 의존함을 보인다. 또한, 계층적 협력 기술은 2 < ${\alpha}$ < 3에서 우월하지만 ${\alpha}{\geq}3$에 대해서는 다중 홉 라우팅을 사용하는 것이 더 높은 용량을 취득함이 밝혀진다. 둘째로, m개의 기지국이 초 광 대역 네트워크에 균일하게 분포한 경우, 인프라 구조의 영향 및 이득을 분석한다. 이때, 모든 동작 영역에 대해 전력 제한된 성격 때문에, 유도한 용량 스케일링은 ${\alpha}$에 의존한다. 게다가, 변수 m이 특정 레벨 이상일 때 전체 용량이 m과 함께 선형적으로 스케일함을 보인다. 그러므로 계층적 협력 또는 인프라 구조의 사용은 특정 조건에서 초 광 대역 네트워크의 용량을 개선하는데 도움이 된다.

• 한국경영과학회지
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• 제42권2호
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• pp.35-48
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• 2017

As the technology convergence paradigm emerges, the need for "CIA techniques" to analyze the mutual effects of technology is increasing. However, since the CIA input parameter estimation is difficult, the present study suggests a "CIA input parameter setting model" to alleviate the difficulty of CIA input parameter estimation. This paper is focused on the difference of measurement difficulty by each scale which expert's estimation behavior was defined as measurement activity quantifying the judgment of future technology. Therefore, this model is designed to estimate the input variable as a sequence or isometric scale that is relatively easy to measure, and then converts it into a probability value. The input parameter setting model of the CIA technique consists of three sub-models : 'probability value derivation model', 'influence estimation model', and 'impact value calculation model', in order to develop a series of models the Thurstone V model, Regression Analysis, etc has been used.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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• pp.157-160
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• 2000

In order to design a low complexity and high performance SOVA decoder for Turbo Codes, we need to analyze the decoding performance with respect to several important design parameters and find out optimal values for them. Thus, we use a scaling factor of soft output and a update depth as the parameters and analyze their effect on the BER performance of the SOVA decoder. finally, we shows the optimal values of them for maximum decoding performance of SOVA decoder for 3GPP complied Turbo codes.