• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.101.5-101
• /
• 2001

A linear input/output data-based predictive control with integral action is developed. The control input is obtained directly from the input/output data in a single step. However, the state estimation in subspace identification gives a biased estimate and there is model mismatch when the controller is applied to a nonlinear process. To overcome such difficulties, we add integral action to a linear input/output data-based predictive controller by augmenting the integrated white noise disturbance model and use each of best linear unbiased estimation(BLUE) filter and Kalman filter as a stochastic observer for the unmeasured disturbance. When applied to a continuous styrene polymerization reactor the proposed controller demonstrates.

• 한국소음진동공학회논문집
• /
• 제17권8호
• /
• pp.741-746
• /
• 2007

In this study, transfer path identification and output estimation are simulated by multi-dimension spectral analysis method (MDSA). Multi -input/single-output system give expression the vehicle suspension which each inputs are correlated reciprocally. In case of correlating with inputs, the system needs separating the each input signal by MDSA. Main simulations are about finding effective input by coherent output spectrum and selecting optimal input's number by multiple coherence function. Also, by shielding transfer path of each input, transfer path characteristic is identified in terms of overall integrated contribution level.

• 한국기계연구소 소보
• /
• 통권18호
• /
• pp.125-129
• /
• 1988

This paper proposes a sensitivity technique for analysis of the relationships between input variables (known values) and output variables(unknown values), These design variables are constrained by design equations. Thus, the output variables can be calculated by solving the equations with eliminating the input variables from the equations because the input variables become constants. If the output variables are not satisfied, the values of the input variables must be adjusted by increasing or decreasing the values and then the problem must be solved again. This is called as the iterative design procedure. The sensitivity technique, presented in this paper, gives the sensitivity on the changes of the values of the output variables to the input variables.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
• /
• pp.567-570
• /
• 2002

The LVDS (Low Voltage Differential Signaling) I/O cells, fully compatible with ANSI TIA/ EIA-644 LVDS standard, are designed using a 0.35${\mu}m$ standard CMOS technology. With a single 3V supply, the core cells operate at 1.34Gbps and power consumption of the output driver and the input receiver is 10. 5mW and 4.2mW, respectively. In the output driver, we employ the DCMFB (Dynamic Common-Mode FeedBack) circuit which can control the DC offset voltage of differential output signals. The SPICE simulation result of the proposed output driver shows that the variation of the DC offset voltage is 15.6% within a permissible range. In the input receiver, the proposed dual input stage with a positive feedback latch covers rail-to-rail input common-mode range and enables a high-speed, low-power operation. 5-channels of the proposed LVDS I/O pair can handle display data up to 8-bit gray scale and UXGA resolution.

• 전기학회논문지
• /
• 제62권6호
• /
• pp.767-781
• /
• 2013

In this paper, we proposes the AC input voltage and current sensorless control scheme to control the input power factor and DC output voltage of the three-phase Z-source PWM rectifier. For DC-link voltage control which is sensitive to the system parameters of the PWM rectifier, fuzzy-PI controller is used. Because the AC input voltage and current are estimated using only the DC-link voltage and current, AC input voltage and current sensors are not required. In addition, the unity input power factor and DC output voltage can be controlled. The phase-angle of the detected AC input voltage and estimated voltage, the response characteristics of the DC output voltage according to the DC voltage references, the FFT results of the estimated voltage and current, efficiency, and the response characteristics of the conventional PI controller and fuzzy-PI controller are verified by PSIM simulation.

• 대한산업공학회지
• /
• 제23권2호
• /
• pp.371-383
• /
• 1997

This paper propose a fuzzy regression method using fuzzy neural networks when a membership value is attached to each input-output pair. First, a method of linear fuzzy regression analysis is described by interpreting the reliability of each input-output pair as its membership values. Next, an architecture of fuzzy neural networks with fuzzy weights and fuzzy biases is shown. The fuzzy neural network maps a crisp input vector to a fuzzy output. A cost function is defined using the fuzzy output from the fuzzy neural network and the corresponding target output with a membership value. A learning algorithm is derived from the cost function. The derived learning algorithm trains the fuzzy neural network so that the level set of the fuzzy output includes the target output. Last, the proposed method is illustrated by computer simulations on numerical examples.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 춘계학술대회
• /
• pp.768-773
• /
• 2004

This work deals with the synthesis of discrete-time nonlinear controller for input time-delay existing nonlinear system and proposes a new effective method to compensate the influence of input time-delay. The controller is synthesised by using input/output linearization. Under the circumstance that input time-delay exist, controller have to produce future value that will be needed for system. On account of this reason described, a weighted average predictor of combined states is adopted. Using the discretization via Euler method, numerical simulations about Van der Pol system are performed to evaluate performance of the proposed method.

• 한국건축시공학회지
• /
• 제11권3호
• /
• pp.247-255
• /
• 2011

한국은행에서 2000년도에 발행된 산업연관표를 적용한 주요 건축자재의 에너지소비량과 $CO_2$ 배출에 대한 원단위 DB는 있지만 2005년, 2007년에 발행된 산업연관표를 이용한 원단위 DB는 없는 실정이다. 본 연구에서는 최근에 발행된 2005년, 2007년도 산업연관표를 이용하여 주요 건축자재에서 발생되는 에너지소비량 및 $CO_2$ 배출 원단위 값을 산정하고자 한다. 주요 건축자재의 에너지소비량 및 $CO_2$ 배출원단위 산출을 위한 방법은 산업연관표를 이용한 DB 구축 방식을 바탕으로 산출하였으며, 건설현장에서 주로 사용되는 16가지의 건설자재는 선별하여 적용하였다. 기존 연구결과에서 제시한 2000년도 산업연관표를 적용하여 산출된 원단위 DB 값과 비교한 결과 근소한 차이를 보이고 있어 본 연구의 산출방법이 적정한 것으로 판단하였다. 2005년, 2007년도 산업연관표를 이용하여 산출한 에너지소비량과 $CO_2$ 배출 원단위 값은 감소세를 보이고 있는 것으로 나타났으며, 시멘트와 철근을 주원료로 하는 자재에서 가장 많은 에너지소비량 및 $CO_2$ 배출 원단위 값을 나타났다. 본 연구의 결과를 통해 국내 실정에 적합한 건설자재 생산단계에서 발생되는 환경부하의 간접적인 예측이 가능할 것으로 사료된다.

• 한국건설관리학회논문집
• /
• 제13권5호
• /
• pp.94-102
• /
• 2012

최근 글로벌 금융위기, 미분양 주택의 증가 등으로 인해 건설기업의 효율성 분석이 요구되고 있다. 기업에 대한 효율성 분석시 가장 중요한 것은 효율성 측정에 사용된 투입-산출변수이다. 하지만 건설기업의 효율성 분석에 중요한 영향을 미치는 핵심적인 투입-산출변수를 추출하기 위한 체계적인 연구는 미흡하였다. 따라서 본 연구에서는 건설기업의 효율성 분석을 위한 핵심 투입-산출변수를 추출을 위해 투입-산출변수 별로 모든 조합을 제시한 모형을 제시하고 DEA모형과 PCA분석을 통하여 건설기업의 효율성을 분석에 중요한 요소인 투입-산출변수를 추출하고자 한다. 본 연구를 위해 기존 연구 및 이론적 고찰을 하고, 효율성 측정을 위한 변수 및 21개 모형을 설정하였다. 다음으로 효율성 및 PCA분석을 하고 결과를 도출하였다. 연구 결과, 핵심적인 투입 및 산출변수는 2006년의 경우 투입변수는 종업원수, 산출변수는 매출액, 2008년의 경우 투입변수는 자본금, 산출변수는 당기순이익, 2010년의 경우 투입변수는 고정자산, 산출변수는 매출액으로 나타났다. 건설기업 효율성 결과에 중요한 영향을 주는 변수 추출을 통해 개별 건설기업들이 효율성을 향상하기 위한 중점전략을 마련할 수 있을 것으로 판단된다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
• /
• pp.830-833
• /
• 2004

Voltage step-down characteristics of Ring/Dot type piezoelectric transformer were examined with increasing input voltage from $10\;V_{pp}$ to $140V_{pp}$. Then the output load resistance was fixed to $125\;\Omega$. The voltage gain showed constant value till the input voltage of $70\;V_{pp}$. And then it linearly decreased till the input voltage of $140V_{pp}$. The output voltage of fabricated piezoelectric transformer increased with increasing input voltage. And driving frequencies when the output voltage was maximum value were changed according to input voltage. Frequency shifts and temperature rise of fabricated sample showed 2 kHz, $13^{\circ}C$, respectively when input voltage was changed from $10\;V_{pp}$ to $140V_{pp}$. Because of the temperature rise of fabricated piezoelectric transformer, the step-down characteristics of it was deteriorated above the input voltage of $70\;V_{pp}$.