• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.573-580
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• 2006

The Saturation headway is a major parameter in estimating the intersection capacity and setting the signal timing. But Existing algorithms are still far from being robust in dealing with factors related to the variation of saturation headways at signalized intersections. So this study apply the fuzzy inference system using ANFIS. The ANFIS provides a method for the fuzzy modeling procedure to learn information about a data set, in order to compute the membership function parameters that best allow the associated fuzzy inference system to track the given input/output data. The climate conditions and the degree of brightness were chosen as the input variables when the rate of heavy vehicles is 10-25 %. These factors have the uncertain nature in quantification, which is the reason why these are chosen as the fuzzy variables. A neuro-fuzzy inference model to estimate saturation headways at signalized intersections was constructed in this study. Evaluating the model using the statistics of $R^2$, MAE and MSE, it was shown that the explainability of the model was very high, the values of the statistics being 0.993, 0.0289, 0.0173 respectively.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.4
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• pp.112-122
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• 1999

In realistic control systems the nonlinear saturation attributes of the control actuator due to physical limitations should be taken into account This nonlinear saturation of actuators may cause not only deterioration of the control performance but also a large overshoot during start-up and shut-down. As the overshoot increases the system may become oscillatory unstable. in this paper the supervisor implementation which guarantees good performance for saturation operation and prevents reset wind up is presented, Moreover the sufficient conditions of the stability for saturated system using supervisory control with a dynamic controller are provided in the continuous-time and in the discrete-time domain Numerical example is illustrated to depict the efficiency of supervisory control for a typical satuaurated production-distribution system controlled by a discrete-time dynamic controller and to validate basic results by simulation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.3
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• pp.459-463
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• 2002

We studied the effect of gain recovery at the optical fiber amplifier by the input pulse trains We also theoretically analyzed the limitation of the saturation and recovery time for the PDFA(Praseodymium-Doped Fiber Amplifier) which has the spectral gain at 1.3${\mu}{\textrm}{m}$ band. We can predict the interval between the pulse train, pump power, and the effect of the saturation and recovery time which is affected to the amplification of the optical pulse.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1184-1187
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• 2002

In this paper, we propose a Rail-to-Rail OTA using equivalent MOSFETs without cutoff region, which operate in triode and saturation regions. The proposed circuit has a merit that its input range is not limited due to voltage drop of current mirrors. The simulation results of the proposed circuit are shown. From the simulation results, the linearity of the proposed circuit is improved when input voltage is from 2V to 3V.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2040-2042
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• 2002

In this paper, we consider the design of gam scheduled controllers for linear systems with input saturation. We obtain a reachable set and a control gain, which guarantees that the controls are never saturated inside this reachable set and that the $L_2$ gain is minimized, from matrix inequalities. This proposed gain scheduled control gives better performance than that of static control case, and we present the simulation results to show the usefulness of the proposed control.

• Journal of Power System Engineering
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• v.11 no.1
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• pp.134-139
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• 2007

A delivery ship is used to handle the cargo with the crane to/from the ships. The ship is inclined in the direction of a cargo which is hung on a crane. In this case, a arc shaped rail should be in the equilibrium state to get good anti-rolling performance. In this study, a device and control algorithm are developed to take accurate and quick equilibrium of the rail. The device is composed of a hinged immovable support, screw jack and damper. And the control system is based on I-PD control law to consider of control input saturation and overshoot. The controller is composed of integral controller of feedforward path and proportional-derivative controller of feedback path. The parameters of controller is designed to follow the reference signal and to remove overshoot. The simulation results show that the desirable control performance is achieved.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.505-508
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• 2002

We studied the effect of gain recovery at the optical fiber amplifier by the input pulse trains. We also theoretically analyzed the limitation of the saturation and recovery time for the PDFA(Praseodymium-Doped Fiber Amplifier) which has the spectral gain at 1.3${\mu}{\textrm}{m}$ band. We can predict the interval between the pulse train, pump power, and the effect of the saturation and recovery time which is affected to the amplification of the optical pulse.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.211-224
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• 2019

This paper deals with a nonlinear controller based on saturation functions with variable parameters for set-point regulation and trajectory tracking control of an Autonomous Underwater Vehicle (AUV). In many cases, saturation functions with constant parameters are used to limit the input signals generated by a classical PD (Proportional-Derivative) controller to avoid damaging the actuators; however this abrupt bounded harms the performance of the controller. We, therefore, propose to replace the conventional saturation function, with constant parameters, by a saturation function with variable parameters to limit the signals of a PD controller, which is the base of the nonlinear PD with gravitational/buoyancy compensation and the nonlinear PD + controllers that we propose in this paper. Consequently, the mathematical model is obtained, considering the featuring operation of the underwater vehicle LIRMIA 2, to do the stability analysis of the closed-loop system with the proposed nonlinear controllers using the Lyapunov arguments. The experimental results show the performance of an AUV (LIRMIA 2) for the depth control problems in the case of set-point regulation and trajectory tracking control.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.12 no.2
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• pp.101-107
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• 2012

This study describes a proposed method of converting an input sound signal into a color image by emulating human synesthetic skills which make it possible to associate an sound source with a specific color image. As a first step of sound-to-image conversion, features such as fundamental frequency(F0) and energy are extracted from an input sound source. Then, a musical scale and an octave can be calculated from F0 signals, so that scale, energy and octave can be converted into three elements of HSI model such hue, saturation and intensity, respectively. Finally, a color image with the BMP file format is created as an output of the process of the HSI-to-RGB conversion. We built a basic system on the basis of the proposed method using a standard C-programming. The simulation results revealed that output color images with the BMP file format created from input sound sources have diverse hues corresponding to the change of the F0 signals, where the hue elements have different intensities depending on octaves with the minimum frequency of 20Hz. Furthermore, output images also have various levels of chroma(or saturation) which is directly converted from the energy.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.37 no.5
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• pp.22-33
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• 2000

Since the heavy-duty power manipulator generally has high ratio gear reducers at its joints, its dynamic characteristics is much slower than that of the master manipulator and it is likely to encounter the saturation in the input magnitude when it is used as the slave manipulator in telemanipulation systems. This paper proposes a force reflecting and compliant control scheme for the heavy-duty power telemanipulator. The main advantage of the proposed scheme is that it provides a precise position and compliant control performance for a telemanipulator with control input saturation. The stability of the proposed scheme is analyzed and a series of experiments shows its performance.