• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1410-1413
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• 1993

This paper presents the application of fuzzy control to three links of a Rhino robot and compares its performance to traditional PD control. The dynamics of motion of robot links are governed by nonlinear differential equations. The fuzzy controller, being an adaptive technique, gives better performance than the traditional linear PD controller over a typical operational range. The fuzzy controller reaches the desired position with no overshoot, which is unlikely with the PD controller.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2089-2091
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• 2001

In this paper, a hybrid controller that consists of a conventional PD controller and a neural network controller which adapts to various control conditions by online learning is used and a new learning algorithm of the neural networks is used to prevent weights of neural network from diverging. A conventional PI controller and the hybrid controller is applied to speed control of 3 phase induction motor. So in comparison with a PD controller, we prove superiority of hybrid controller by experiments.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.67.1-67
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• 2001

This paper presents a neural network based self-tuning fuzzy PI-PD control scheme for robust speed control of induction motor. The PID controller is being widely used in industrial applications. When continuously used long time, the electric and mechanical parameters of induction motor change, degrading the performance of PID controller considerably. This paper re-analyzes the fuzzy controller as conventional PID controller structure, and proposes a neural network based self-tuning fuzzy PI-PD controller whose scaling factors are adjusted automatically. Proposed scheme is simple in structure and computational burden is small ...

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.351-354
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• 2006

In underwater environment, the control of AUV is difficult, because of the existence of parameter uncertainties and disturbances as well as highly nonlinear and coupled system dynamics. The requirement for the simple and robust controller which works satisfactorily in those dynamical uncertainties, call for a design using the PD or sliding mode controller. The PD controller is very popular controller in the industrial field and the sliding mode controller has been used successfully for the AUV controller design. In this paper, the two controllers arc designed for ISiMI(Integrated Submergible Intelligent Mission Implementation) AUV and the performances are compared by numerical simulation under the modeling uncertainty and disturbances. The design process of PD and sliding mode controller for ISiMI AUV and simulation results are included to compare the performances of the two controllers.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.17 no.1
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• pp.13-17
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• 2011

There is a need in food industry to store minimally processed garlic for long time to have it be used just at the time of demand for final product processing. Optimal modified atmosphere packaging is expected to slow down the quality change extending its storage life. In order to find optimal packaging conditions, plastic films of different gas permeability properties (low density polyethylene (LDPE) $30{\mu}m$, polyolefin $50{\mu}m$ (PD 900), polyolefin $20{\mu}m$ (PD 941)) were used for packaging 400 g of minimally processed garlic. Perforated LDPE packages were prepared as control. The packaged products were stored at $1{\pm}1^{\circ}C$ for 52 days. Package treatments were compared in weight loss, decay, surface color, hardness and soluble solid content. While control package had normal atmosphere of air, LDPE, PD 900 and PD 941 packages attained internal concentration of $O_2$ 4.6% / $CO_2$ 12%, $O_2$ 0.9% / $CO_2$ 21% and $O_2$ 0.5% / $CO_2$ 13% after 45 days, respectively. Control packaging had rapid weight loss with high mold decay and great surface color change in 45 days. In PD 900 film packages of lowest gas permeability, the fresh-cut garlic could be stored without mold decay for 52 days. Except control packaging, there were no significant differences in surface color, hardness and soluble solid content among package treatments.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.6
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• pp.15-22
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• 2005

In this paper, we propose a PID-PD controller and its tuning method to be modified form of PID controller that consist of the affine set of PID and PI-PD controller by analyzing relation between these controllers. The proposed tuning method controls the closed-loop system to locate between the step responses of system controlled by PID and PI-PD controller. The controller is designed by the optimum tuning method to minimize the proposed specific cost functions. Its effectiveness is examined by the case studies and their analysis.

• International Journal of Ocean System Engineering
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• v.3 no.1
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• pp.16-21
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• 2013

This paper presents a design of fuzzy PD depth controller for the autonomous underwater vehicle entitled KAUV-1. The vehicle is shaped like a torpedo with light weight and small size and used for marine exploration and monitoring. The KAUV-1 has a unique ducted propeller located at aft end with yawing actuation acting as a rudder. For depth control, the KAUV-1 uses a mass shifter mechanism to change its center of gravity, consequently, can control pitch angle and depth of the vehicle. A design of classical PD depth controller for the KAUV-1 was presented and analyzed. However, it has inherent drawback of gains, which is their values are fixed. Meanwhile, in different operation modes, vehicle dynamics might have different effects on the behavior of the vehicle. In this reason, control gains need to be appropriately changed according to vehicle operating states for better performance. This paper presents a self-tuning gain for depth controller using the fuzzy logic method which is based on the classical PD controller. The self-tuning gains are outputs of fuzzy logic blocks. The performance of the self-tuning gain controller is simulated using Matlab/Simulink and is compared with that of the classical PD controller.

• Journal of Korean Physical Therapy Science
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• v.9 no.2
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• pp.159-170
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• 2002

Parkinson's disease(PD) is a progressive neurodegenerative disease that affects the functioning of the basal ganglia, a brain area that contributes to the control of movement. The disease is caused by the death of nerve cells in the brain that produce dopamine, a chemical messenger. The cells affected usually produce a neurotransmitter(a chemical that transmits nerver impulses) called dopamine, which acts with acetylcholine, another neurotransmitter, to fine-tune muscle control. In Parkinson's disease, the level of dopamine relative to acetylcholine is reduced, adversely affecting muscle control. When the supply of dopamine is depleted, the function of the basal ganglia is disrupted and its ability to control movement-deteriorates. The result is that PD patients experience moderate rigidity, difficulty in initiating movements and slowness in executing them, and a rhythmical tremor at rest. Although the cause of Parkinson's disease is not known, genetic factors may be involved. About 3 in 10 people with the disorder have an affected family member. About 1 in 100 people over the age of 60 in the US have Parkinson's disease. And Parkinson's disease is slightly more common in men. The course of the disease is variable, but drags may be the best effective in treating the symptoms and improving quality of life. But, The doctor may arrange physical therapy to help with physical mobility problems. It is important to continue to exercise and take care of your general health. Try to take a walk each day. Stretching exercises can help you maintain your strength and mobility. So, This papers will serve about the information of PD for clinical physical therapist. Finally, The aim of review is increasing approach method and technique for PD patients by the view of physical therapy.

• Journal of Society of Preventive Korean Medicine
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• v.25 no.3
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• pp.25-37
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• 2021

Objectives : To investigate the effectiveness of Korean Medicine services use on the all-cause mortality and incidence of Parkinson's disease(PD) in elderly patients with chronic disease based on the National Health Insurance Service Corhort Database (elderly), called as the NHIS-senior. Methods : This study was a retrospective cohort analysis conducted using the NHIS-senior. Patients with chronic diseases over 65 years old who were not diagnosed PD during 2007-2009 were identified. The case group was defined as patients who used both Korean Medicine and Western Medicine services and the control group consisted of patients who used Western Medicine service only. The all-cause mortality and incidence of PD was analyzed using the Cox proportional hazard model after a propensity score matching(PSM) with a 1:1 ratio. Results : After PSM, the cohort included 47,546 subjects (23,773 in the case group, 23,773 in the control group). Sex, age, comorbidity, severity of disability, and neurology medical service utilization were adjusted in both groups. The mortality was 0.668 times (95% C.I.: 0.646-0.690) lower in the case group than the control group, which was statistically significant (p<0.001). The incidence of PD was 1.051 times (95% C.I.: 0.962-1.148) higher in the case group than the control group, which was not statistically significant(p=0.272). Conclusion : It was not obvious that the use of both Korean Medicine service and Western Medicine services for prevention of PD is benefitial than using only Western Medicine. But it would be possible that using both Korean Medicine and Western Medicine services decreases the mortality than using Western Medicine alone.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.3
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• pp.110-120
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• 1996

The purpose of this study is to build up the control scheme that promptly controls the pressure in a hydraulic cylinder having small control volume, using a PCV(proportional control valve) and a digital computer. Object pressure control system has the character to be unstable easily, because the displacement-flow gain of the PCV is so large considering comparatively small volume of the hydraulic cylinder and the time delay of response of PCV is long. Considering the above-mentioned characteristics of the object pressure control system, in this study, a control system is designed with two degree of freedom scheme that is composed by adding a feed-forward control path to I-PD control system, and the reference model is used to decide control parameters. And through some experiments on FF-I-PD, the validity of this control method is confirmed.