• 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.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.671-680
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• 2016

This research suggested a new real-time traffic signal control algorithm using fusion data of the travel time and the occupancy rate. This research applied the travel time data of traffic information system to traffic signal operation, and developed the signal control process using the degree of saturation that was estimated from the travel time data. This algorithm estimates a queue length from the travel time based on a deterministic delay model, and includes the process to change from the queue length to the degree of saturation. In addition, this model can calculate the traffic signal timings using fusion data of the travel time and the occupancy rate based on the saturation degree. The micro simulation analysis was conducted for effectiveness evaluation. We checked that the average delay decreased by up to 27 percent. In addition, we checked that this signal control algorithm could respond to a traffic condition of oversaturation and detector breakdown effectively and usefully. This research has important contribution to apply the traffic information system to traffic signal operation sectors.

• Quality Improvement in Health Care
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• v.12 no.1
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• pp.92-102
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• 2006

Background : Most hospitalized children will experience physical pain as well as psychological distress. Painful procedure can increase anxiety and fear of pediatric patients and their parents who do not have understanding logical of their disease and hospitalization. This study attempted to identify pain reduction in related to therapeutic intervention by age and environmental improvement. Methods : A total of 194 hospitalized children and their parents were investigated. Data collection period was 3 months from March to May 2004. Four instruments were used to collect the data : Faces Pain Rating Scale(FPRS), Heart rate, Oxygen saturation and Pain behavioral check list. The data were analyzed by a SPSS program and tested x2-test, t-test, ANCOVA. Results : 1. Age from 0 to 3, the Heart rate, FPRS, Oxygen saturation and Pain behavioral check list were significantly different in theraputic intervention group when compare to control group. 2. Age from 4 to 6, FPRS, Oxygen saturation and Pain behavioral check list were significantly different in theraputic intervention group when compare to control group. But the heart rate were not significantly different when compare to control group. 3. Age from 7 to 9, FPRS and Pain behavioral check list were significantly lower in therapeutic intervention group when compare to control group but Heart rate and Oxygen saturation were not significantly different when compare to control group. Conclusion : The results of this study concludes that most children experience acute pain during IV therapy and it can be reduced by age specific therapeutic intervention and by change of surrounding environment.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1770-1773
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• 1997

In this paper, a linear discrete time system subject to the input saturatioin is shown to be exponentially stabilizable on any compact subset of the constrained asymptotically stabilizable set by a linear periodic variable structure controller. We also establish tat any neutrally stable system subject to the input saturation can be globally asymptotically stabilizable via linear feedback.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.189-194
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• 1993

This paper presents an ARW(Anti-Reset Windup) method for discrete-time control systems with saturation nonlinearites. The method is motivated by the concept of the equilibrium point. The design parameters of the ARW scheme is explicitly derived by minimizing a reasonable performance index. The proposed method is closely related with the singular perturbed theory. The proposed method is applicable to any open-loop stable plants with saturation nonlinearities whose controllers are determined a priori by some design technique.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.23 no.2
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• pp.63-68
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• 2015

This paper presents the algorithm for envelope protection of helicopters. The algorithm consists of two feedback control loops: inner loop and outer loop. As an inner loop control, model following control is designed to meet the ADS-33 handling qualities specification by minimizing the tracking errors between the responses of the actual model and those of the command filter. In order to implement envelope protection, saturation limiter is imposed to command channels in command filter, whose limits are computed corresponding to the envelope limit. Fast model predictive control is designed as an outer loop control to deal with saturation constraints generated by the inner loop envelope protection and also imposed by outer loop envelope protection variables. Simulation results show that the proposed algorithm yields good envelope protection performance.

• Proceedings of the KIEE Conference
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• 2003.11b
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• pp.335-338
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• 2003

In this paper, we considered the design of gain scheduled controllers for linear systems with input constraints. The gain scheduled control is a method that uses larger control gain when the states are smaller, and smaller gain when it is larger. By doing this, we can use a full actuator capacity. Also we allow the over-saturation in control to improve the performance. First, we derive a control and a reachable set expressed as LMI form, while minimizing the $L_2$ gain from the disturbance to the measured output. Next, the reachable set is divided as nested subsets, and the control gains are obtained by minimizing the $L_2$ gain at each nested subset. Finally, the control gains are scheduled according to the status of states, i.e., the nested-subset in which the states are located. Performance of the proposed technique is illustrated through simulations of a six-story building subject to earthquake ground motion.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.3
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• pp.156-165
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• 1997

In the practical control systems, the dynamic range of actuatiors is limited(or saturated) when actuators are driven by sufficiently large signals. This gives rise to a nonlinearity as a result of actuator saturation. For example, the upper limit is imposed on productive capability by available factory space and capital equipment. Other examples of those kinds of actuator saturations are a maximum torque of the actua- ting motors and a throttle position in an aircraft speed control A saturating actuator may lead not only to a large overshoot during start-up and shut-down, but also to deterioration of the performance due to the uncertainties. That is, the speed of response is decreased and, possibly, the system output may not follow the lalrge reference inputs. The large-overshoot may be accompanied by rest wind-up(or called by integra- tor wind-up) which comes from controllers with integral action in saturation operation regions. Eventually, as the overshoot increases, the system has a limit cycle or becomes oscillatorily unstable. Due to these cir- cumstances, many studies are focused on the stability and robustness of the nonlinear systems with satu- rating actuator in the time-domain as well as in the frequency-domain.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.16 no.3
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• pp.301-309
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• 2003

The non linear control algorithm with actuator saturation for a randomly excited oscillator has been widely explored and has shown promising results, but the probabilistic analysis of the algorithm has been rarely made due to its non-linear nature and the fact that the analytical solution of probability density function (PDF) for controlled responses does not exist. In this paper, a method for the probabilistic analysis on the non linear control algorithm with actuator saturation is proposed based on the equivalent non linear system method. Numerical examples are given to verify the approximation solution of PDF comparing to a statistically obtained PDF using a Gaussian white noise and a Kanai - Tagimi filtered Gaussian white noise.

• Women's Health Nursing
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• v.15 no.1
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• pp.32-42
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• 2009

Purpose: This study was done to examine the effects of abdominal breathing on VAS-Anxiety (VAS-A), blood pressure, peripheral skin temperature and saturation oxygen in pregnant women in preterm labor. Method: The study design was a matched control group interrupted time series. Forty-six women matched to gestational age were assigned to either the experimental group (26) or control group (20). Data were collected between March 2007 and May 2008. For the experimental treatment the women performed abdominal breathing 30 times, which took 5 minutes, and did one set of 5-minute abdominal breathing daily for three days. Data collection was done before and after the abdominal breathing to measure VAS-A, blood pressure, peripheral skin temperature and oxygen saturation. Descriptive, $X^2$, Mann-Whitney U tests were used to analyze the data with the SPSS/PC+Win 15.0 program. Result: For the experimental group there were significant decreases in VAS-A (Z=-4.37, p=.00), systolic blood pressure (Z=-3.38, p=.00), and an increase in skin temperature (Z=-4.50, p=.00) and oxygen saturation (Z=-3.66, p=.00). Conclusion: These findings suggest that abdominal breathing in pregnant women in preterm labor results in decreases in anxiety(VAS-A) including biological evidences such as systolic blood pressure, and increases in peripheral skin temperature and oxygen saturation. Further longitudinal study is needed on the lasting effects and obstetric and neonatal outcomes following abdominal breathing.