• 제목/요약/키워드: input coefficient

검색결과 1,027건 처리시간 0.028초

적분 슬라이딩 모드 제어기를 이용한 출력 궤환 안정화 (Output Feedback Stabilization using Integral Sliding Mode Control)

  • 오승록
    • 대한전기학회논문지:시스템및제어부문D
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    • 제52권3호
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    • pp.142-147
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    • 2003
  • We consider a single-input-single-output nonlinear system which can be represented in a normal form. The nonlinear system has a modeling uncertainties including the input coefficient uncertainty. A high-gain observer is used to estimate the states variables to reject a modeling uncertainty. A globally bounded output feedback integral sliding mode control is proposed to stabilize the closed loop system. The proposed integral sliding mode control can asymptotically stabilize the closed loop system in the presence of input coefficient uncertainty.

Correlation between chloride-induced corrosion initiation and time to cover cracking in RC Structures

  • Hosseini, Seyed Abbas;Shabakhty, Naser;Mahini, Seyed Saeed
    • Structural Engineering and Mechanics
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    • 제56권2호
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    • pp.257-273
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    • 2015
  • Numerical value of correlation between effective parameters in the strength of a structure is as important as its stochastic properties in determining the safety of the structure. In this article investigation is made about the variation of coefficient of correlation between effective parameters in corrosion initiation time of reinforcement and the time of concrete cover cracking in reinforced concrete (RC) structures. Presence of many parameters and also error in measurement of these parameters results in uncertainty in determination of corrosion initiation and the time to crack initiation. In this paper, assuming diffusion process as chloride ingress mechanism in RC structures and considering random properties of effective parameters in this model, correlation between input parameters and predicted time to corrosion is calculated using the Monte Carlo (MC) random sampling. Results show the linear correlation between corrosion initiation time and effective input parameters increases with increasing uncertainty in the input parameters. Diffusion coefficient, concrete cover, surface chloride concentration and threshold chloride concentration have the highest correlation coefficient respectively. Also the uncertainty in the concrete cover has the greatest impact on the coefficient of correlation of corrosion initiation time and the time of crack initiation due to the corrosion phenomenon.

폭기공정의 물질전달 계수와 기체 포집율 및 소요동력의 상관관계에 대한 비교연구 (Comparison Study on Empirical Correlation for Mass Transfer Coefficient with Gas Hold-up and Input Power of Aeration Process)

  • 박상규;양희천
    • 대한기계학회논문집B
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    • 제41권6호
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    • pp.415-421
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    • 2017
  • 환경규제의 강화에 따라 수처리 비용이 증가하는 추세이므로 폭기공정의 에너지 이용효율을 제고할 수 있는 소요동력에 대한 보다 정량적인 연구가 필요하다. 본 논문은 폭기공정의 물질전달 특성을 규명하기 위해 물질전달 계수와 기체 포집율 및 소요동력에 대한 상관관계식을 제시하였다. 소요동력이 커지면 기체 포집율은 감소하고 레이놀드 수는 증가하며, 혼합유동 선단 도달거리와 확산도가 증대되므로 물질전달 계수는 증가하였다. 물질전달 계수와 기체 포집율 및 소요동력의 상관관계 규명을 위해 제시한 실험식은 최대 약 ${\pm}10%$의 오차 범위에서 실험결과와 일치하였다.

PZT계 압전변압기의 공진특성과 전기적 성질 (Resonance characteristics and electrical properties of PZT-piezoelectric transformer)

  • 박순태;정수태;이종헌
    • E2M - 전기 전자와 첨단 소재
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    • 제8권1호
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    • pp.27-34
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    • 1995
  • The analysis of nonlinear equivalent circuit and the resonance characteristics of input current and output voltage were simulated, and their electrical properties are discussed in the transverse-type piezoelectric ceramic transformer. The nonlinear resonance characteristics of input current and output voltage showed by the thermal effect due to a higher driving current, the nonlinearity increased greatly as driving current increased. When load resistor was 100[M.ohm.], the nonlinear coefficient was -1.3. The nonlinear resonance curve of input current and output voltage for a variation of input voltage and load resistor agreed with the discussed theory. The output voltage increased nearly proportioned to input voltage when load resistors were below 50[M.ohm.], the voltage step-up ratio decreased when a load resistor was 100[M.ohm.] and their maximum value was 950.

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신경망을 이용한 판온예측모델내 공정상수 설정 방법 (A Computing Method of a Process Coefficient in Prediction Model of Plate Temperature using Neural Network)

  • 김태은;이해영
    • 조명전기설비학회논문지
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    • 제28권11호
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    • pp.51-57
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    • 2014
  • This paper presents an algorithmic type computing technique of process coefficient in predicting model of temperature for reheating furnace and also suggests a design method of neural network model to find an adequate value of process coefficient for arbitrary operating conditions including test conditons. The proposed neural network use furnace temperature, line speed and slab information as input variables, and process coefficient is output variable. Reasonable process coefficients can be obtained by an algorithmic procedure proposed in this paper using process data gathered at test conditons. Also, neural network model output equal process coefficient under same input conditions. This means that adquate process coefficients can be found by only computing neural network model without additive test even if operating conditions vary.

전력용 HEMT를 이용한 1740~1780MHz 대역의 MMIC 전력증폭기 설계 (Design of MMIC Power Amplifier using Power HEMT at 1740~1780MHz)

  • 윤관기;조희철이진구
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 추계종합학술대회 논문집
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    • pp.675-678
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    • 1998
  • In this paper, power amplifiers for PCS phone were designed with the GEC Marconi H40 HEMT libray. The 1st stage was carefully designed in order to obtain k〉1 using a parallel resistor, and its S21 gain of 18.3dB and input reflection coefficient of -4dB were obtained. And S21 gain of 18dB and input reflection coefficient of -7dB were obtained from the 2nd stage. Finally, total S21 gain of 38dB, input reflection coefficient of -16dB, power gain of 35.2dB, output power of 28.7dBm and PAE(power added efficiency) of 29% were obtained from the designed MMIC power amplifiers. The chip size is $1.729$\times$0.94\textrm{mm}^2.$

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인공신경망기법에 상관계수를 고려한 서울 강우관측 지점 간의 강우보완 및 예측 (Rainfall Adjust and Forecasting in Seoul Using a Artificial Neural Network Technique Including a Correlation Coefficient)

  • 안정환;정희선;박인찬;조원철
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2008년도 정기총회 및 학술발표대회
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    • pp.101-104
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    • 2008
  • In this study, rainfall adjust and forecasting using artificial neural network(ANN) which includes a correlation coefficient is application in Seoul region. It analyzed one-hour rainfall data which has been reported in 25 region in seoul during from 2000 to 2006 at rainfall observatory by AWS. The ANN learning algorithm apply for input data that each region using cross-correlation will use the highest correlation coefficient region. In addition, rainfall adjust analyzed the minimum error based on correlation coefficient and determination coefficient related to the input region. ANN model used back-propagation algorithm for learning algorithm. In case of the back-propagation algorithm, many attempts and efforts are required to find the optimum neural network structure as applied model. This is calculated similar to the observed rainfall that the correlation coefficient was 0.98 in missing rainfall adjust at 10 region. As a result, ANN model has been for suitable for rainfall adjust. It is considered that the result will be more accurate when it includes climate data affecting rainfall.

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산업연관분석을 통한 공간정보산업의 특징 및 정책방향성에 대한 연구 (A Study on Strategy Direction for Promoting the Geo-spatial Information Industry by Input-Output Analysis)

  • 임시영;안종욱;이미숙
    • Spatial Information Research
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    • 제20권6호
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    • pp.69-76
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    • 2012
  • 본 연구에서는 산업연관분석을 통해 공간정보산업의 특징을 도출하였다. 이를 위하여 공간정보산업을 재분류하고 이에 맞게 산업연관표를 수정하여 공간정보산업을 분석하였으며 생산유발계수, 영향력계수, 감응력계수를 도출하였다. 그 결과 공간정보산업은 생산유발효과는 작으나 전방연쇄효과가 매우 큰 산업으로 확인되었다. 이를 기반으로 공간정보산업 육성을 위한 정책의 방향성을 '산업생태계 조성, 고도화와 활용도 향상 병행, 장기적 관점 수립'으로 제시하였다.

소프트웨어산업과 의료산업이 한국경제에 미치는 파급효과 (The Impact of Software and Medical Industry on Korea Economy)

  • 윤은경;문준환;최항석
    • 한국IT서비스학회지
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    • 제17권2호
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    • pp.49-67
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    • 2018
  • This study compares economic impact between Software and Medical industry through Input Output Table by Bank of Korea. We classify Software and Medical industry by The ninth Korea Standard Industry Classification and use linkage effects, value added inducement coefficient, and labor inducement coefficient to analyze economic impact. First, software and medical industry have different linkage effects between backward and forward. Second, They have higher value added inducement coefficient than average of all industry. Third, They not only have higher labor inducement coefficient than average of all industry but also simillar effect on labor induction. According to the result of this study, software and medical industry have high economic impact on Korea economy, and therefore are intensively fostered by policy support.

Input Density에 대한 Compandor 특성에 관한 연구 (A Study On The Computer Characteristics For the Various Input Probability Density Function)

  • 박찬경;한영열
    • 한국통신학회:학술대회논문집
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    • 한국통신학회 1984년도 추계학술발표회논문집
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    • pp.92-95
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    • 1984
  • This paper describes the output P.D.F. of various Compandors, optimum, -law and A-law for the Gaussian and Laplacian Density as an input analog signal. Also we consider the truncated densities compensated by weighted impulse or density coefficient.

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