• International Journal of Precision Engineering and Manufacturing
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• v.3 no.1
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• pp.66-75
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• 2002

The crane operation used fur transporting heavy loads causes a swinging motion with the loads due to the crane\`s acceleration and deceleration. This sway causes the suspension ropes to leave their grooves and can cause serious damage. Ideally, the purpose of a crane system is to transport loads to a goal position as soon as possible without any oscillation of the rope. Currently, cranes are generally operated based on expert knowledge alone, accordingly, the development of a satisfactory control method that can efficiently suppress object sway during transport is essential. The dynamic behavior of a crane shows nonlinear characteristics. When the length of the rope is changed, a crane becomes a time-varying system thus the design of an anti-sway controller is very difficult. In this paper, a nonlinear dynamic model is derived for an industrial overhead crane whose girder, trolley, and hoister move simultaneously. Furthermore, a fuzzy logic controller, based on expert experiments during acceleration, constant velocity, deceleration, and stop position periods is proposed to suppress the swing motion and control the position of the crane. Computer simulation is then used to test the performance of the fuzzy controller with the nonlinear crane model.

• Transactions on Electrical and Electronic Materials
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• v.15 no.3
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• pp.159-163
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• 2014

More accurate CD (Critical Dimension) control is required for the nanometer-scaled devices. However, since the reflectivity between substrate and PR (Photoresist) becomes higher, the CD (Critical Dimension) swing curve was intensified. The higher reflectivity also causes PR notching due to the pattern of sub-layer. For this device requirement, it was optimized for the thickness, refractive index(n) and absorption coefficient(k) in the bottom anti-reflective coating(BARC; SiON) and photoresist with the minimum reflectivity. The computational simulated conditions, which were determined with the thickness of 33 nm, n of 1.89 and k of 0.369 as the optimum condition, were successfully applied to the experiments with no standing wave for the 0.13um-device. At this condition, the lowest reflectivity was 0.44%. This optimum condition for BARC SiON film was applied to the process for 0.13um-device. The optimum SiON film as BARC to PR and sub-layer could be formed with the accurate CD control and no standing waver for the nanometer-scaled semiconductor manufacturing process.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.113-119
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• 2002

Recently, an automatic crane control system is required with high speed and rapid transportation. During the operation of crane system in container yard it is necessary to control the crane trolley position and loop length so that the swing of the hanging container is minimized We can do development of unmanned automation control system using automation travel control technique and anti-sway technique in crane system. Therefore, we designed a controller for Automation travel control to control the transfer crane system. Analyzed crane system through simulation, and proved excellency of control performance than other conventional controllers.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1914-1915
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• 2011

본 논문은 천정형 크레인의 파라미터 추정과 Fuzzy LMI 제어기법을 이용한 흔들림 억제 제어를 제안한다. 실제 크레인을 제어함에 있어서 크레인의 동적모델링 이외에도 미지의 물리적 매개변수 값을 규정하는 것은 중요한 요소이다. 이러한 점을 고려하여 크레인의 물리적 매개변수를 최소자승추정 방법을 통해 추정하여 크레인 제어의 성능향상을 제공한다. 또한 Fuzzy LMI 제어기법을 적용하여 천정형 크레인의 이동 중 발생하는 흔들림을 제어한다.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2473-2475
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• 2000

In this paper, we design a GA-fuzzy controller for position control and anti-swing at the destination point. Applied genetic algorithm is used to complement the demerit such as the difficulty of the component selection of fuzzy controller, namely, scaling factor, membership function and control rules. Lagrange equation is used to represent the motion equation of trolley and load in order to obtain mathematical modelling.

• Journal of Navigation and Port Research
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• v.26 no.5
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• pp.537-542
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• 2002

Recently, an automatic crane control system is required with high speed and rapid transportation. Therefore, when container is transferred from th intial coordinate to the finial coordinate, the container paths should be built in terms of the least time and no swing. So in this paper, we calculated the anti-collision path for avoiding collision in its movement to the finial coordinate. And we constructed the neural network predictive PID (NNPPID) controller to control the precise navigation. The proposed predictive control system is composed of the neural network predictor, PID controller, neural network self-tuner which yields parameters of PID. Analyzed crane system through simulation, and proved excellency of control performance than other conventional controllers.

• Journal of the Korean Society of Physical Medicine
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• v.16 no.2
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• pp.81-90
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• 2021

PURPOSE: Aging causes a decrease in muscle mass and a change in posture, which reduces motor function and makes it difficult to perform daily activities independently. As these factors are closely related to the deterioration of the quality of life, it is very important to prevent and manage negative changes in the musculoskeletal system. Forest healing is a nature therapy course that maintains and promotes health using various environmental factors in a forest. The purpose of this study was to identify the effects of the forest healing anti-aging programs on the physical health of the elderly. METHODS: Ten elderly people participated in this study, as part of a forest healing anti-aging program for two days. Functional fitness, muscle strength, gait function, and balance were evaluated before and after the program. RESULTS: The number of arm curls, chair stands, and steps in a 2-min walk significantly increased (p < .05). 8-feet up & go time was significantly decreased (p < .05). Biceps brachii, quadriceps femoris, and calf muscle strength were significantly increased (p < .05). Gait velocity and cadence were significantly increased (p < .05). Step length, stride length, step time, swing time, stance time, and cycle time were significantly decreased (p < .05). Reaching distance in the lateral directions was significantly increased (p < .05). CONCLUSION: The forest healing anti-aging program improves the physical health of the elderly.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.315-321
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• 2010

Malassezia furfur is an important causal factor for seborrheic dermatitis. Nowadays, the drugs available to treat this fungal infection are few. Several studies have documented the biological activity of essential oils. However, its antifungal properties are not completely understood, especially its anti-Malassezia activity. The aim of this study were to evaluate the effect of the plant essential oils on the growth of M. furfur using disk diffusion method and analyze by Gas chromatography-mass spectrometry (GC-MS) most active essential oils. In first screening, the 17 plant essential oils have possesses inhibitory activity against M. furfur at 2 mg/mL. Among the plant essential oils, oil of Citrus auranifoli was most active against M. furfur and its activity showed dose dependency. This anti-malassezial activity was high than that of itraconazole at 2 mg/mL. Oil of Citrus auranifolia also was phytochemically examined by GC-MS analysis, its main constituents were identified as limonene, ${\gamma}$-terpinene and terpinolene. It can be concluded that essential oils of Citrus auranifolia may have interesting applications to control fungal-derived diseases.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.5
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• pp.527-535
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• 2009

This paper describes the control system to suppress the load pendulation using tagline for the floating crane. Dynamic equation of motion of the floating crane and the load is derived using Newton's 2nd law and free body model. The floating crane and the load are assumed that they move in center plane. Each rigid body has 3 DOF (surge, heave, pitch), because it moves in two directions and rotates. Then, this system, which is composed of two rigid bodies, has 6 DOF. The gravitational force, the hydrostatic force, the hydrodynamic force and the tension of the wire rope are considered as external forces, which affect to the floating crane. To suppress the pendulation of the load, the tagline, which connects between the load and the float crane, is applied to the system. The tagline is composed of the spring and the wire rope. Proportional and Derivative control is used as a linear control algorithm. The results of the numerical analysis of the 3,600 ton floating crane show that the tagline system is effective to suppress the load pendulation.