• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.11
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• pp.1656-1663
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• 2004

As the structures become larger, higher and more complicated, the demand for safety level has increased. In recent years, TLD(Tuned Liquid Damper) proved to be a successful control tool for reducing structural vibrations. For this reason, the influence of some key parameters of the U-type TLD on the dynamic response is studied. And simple and effectively developed learning control logic is used to control vibration of U type Tuned Liquid Damper system. The purpose of this paper is design optimal control system to deal with unknown errors from non linearity and variation that cost modeling difficulty in complex structure and is followed with the desired behavior. Finally this hybrid control method applied to U type Tuned Liquid Damper structure gives the benefit from better performance of precision and stability of the structure by reducing vibration effect. This research leads to safety design in various structure to robust unspecified foreign disturbances such as windy-load and earthquake.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.2
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• pp.71-79
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• 2022

The aim of this study is to see how government spending on education, health, and social security affects ratios in Indonesia. The third sector has a critical role to play in reducing the dependency ratio. It also aims to lower unemployment and poverty rates. This study uses the GMM panel data model. This model can determine the dynamic response of the ratio that comes from a number of variables. This study uses data from 33 provinces from 2010 to 2018. The results show that government spending in the education and health sectors has a positive effect on the dependency ratio, both in the short and long term. Social security has a significant effect on the dependency ratio in the long term, but not in the short term. Government spending in the education sector and health sector and social security sector have a positive and significant effect on disease and illness. The study's findings show a high level of poverty with a large standard deviation. The high ratio value is due to the large number of restrictions placed on a number of regions. Each province has made a significant contribution to overcoming these challenges, particularly in terms of the comparative ratio.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.11a
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• pp.353-360
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• 2000

A design of PIDA(Proportional-Integral-Derivative-Acceleration) controller for the third-order plant using the CDM(Coefficient Diagram Method) is presented. Using CDM, the closed-loop system with the designed PIDA controller can be made stable and satisfied both the transient and steady state response specifications without any adjustment. The effect of output step disturbance can also be lastly rejected. The fast step response of the controlled system can be achieved by reducing the equivalent time constant. The MATLABs simulation results show that the performances of the designed controlled system using CDM is better than the performance of the controlled system using PIDA controller designed by its own technique.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.867-871
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• 2009

Response surface methodology (RSM) was used for the optimization of antioxidant capacity in gardenia extracts. The antioxidant capacities of gardenia fruit extracts were investigated by ferric reducing ability (FRA) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity (RSA) assays. The optimum extraction parameters for the strongest antioxidant capacity were the ethanol concentration (EtOH) of 48.9%, extraction temperature of $72.9^{\circ}C$, and extraction time of 29.9 min. Analysis of variance (ANOVA) showed that the quadratics of EtOH and extraction temperature had highly significant effect on the antioxidant capacity (p<0.001). The antioxidant capacity was correlated with contents of bioactive components [crocin, geniposide, and total phenolic (TP) compounds] in gardenia extracts and mainly attributed to the content of the TP compounds.

• Journal of Korean Association for Spatial Structures
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• v.16 no.4
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• pp.37-44
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• 2016

The seismic isolation system reduces the seismic vibration that is transmitted from foundation to upper structure. This seismic isolation system can be classified into base isolation and mid-story isolation by the installation location. In this study, the seismic behavior of dome structure with mid-story isolation is analyzed to verify the effect of seismic isolation. Mid-story isolation is more effective than base isolation to reduce the seismic responses of roof structure. Also, this isolation would be excellent in structural characteristics and construction.

• Journal of the Optical Society of Korea
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• v.18 no.4
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• pp.395-400
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• 2014

We proposed a method for fast turn-off switching of a vertically-aligned liquid crystal cell by low-temperature curing of the polymer structure. We confirmed that the turn-off times of the fabricated cells were reduced significantly as the curing temperature was lowered to $-20^{\circ}C$. We accounted for the effect of low-temperature curing on the turn-off time by using a mathematical model and by observing images obtained via scanning electron microscopy. We also confirmed that low-temperature curing is more effective in reducing the response time when the device is operated at a low temperature.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.751-753
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• 1995

Practical controllers of industrial systems are usually designed and realized in continuous time domain. However, due to the programmable and flexible nature of digital computers and the speed and stability superioity of digital components over analog ones, it seems more effective to adapt digital controllers. When an existing analog controller performs satisfactory, it is often advantageous to use the digital redesign techinque to obtain an equlivalent digital controller which substitutes the analog one. One method of the digital redesign is to use a periodic gain. This method gives a riffle effect on the steady state response, although it's transient response is satisfactory. This paper suggests a method which eliminates or deminishes periodic ripples generated by the periodic function.

• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.395-400
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• 1998

A design of PIDA (Proportional-Integral-Derivative-Acceleration) controller for the third-order plant using the CDM (Coefficient Diagram Method) is presented. Using CDM, the closed-loop system with the designed PIDA controller can be made stable and satisfied both transient and steady state response specifications without any adjustment. The effect of output step disturbance can also be lastly rejected. The fast step response of the controlled system can be achieved by reducing the equivalent time constant. The MATLAB's simulation results show that the performances of the designed controlled system using CDM is better than the performances of the controlled system using PIDA controller designed by its own technique.

• Earthquakes and Structures
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• v.24 no.6
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• pp.405-413
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• 2023

Various methods have been used to strengthen structures against earthquakes. Isolator systems are among the methods to control the structure's response. Instead of increasing the strength and capacity of the structure, these systems react to earthquakes. In this paper, an isolator system was investigated with the flexible piers of ∨ and ∧ elements, which were perpendicular to each other and connected by a rod hinged at both ends. The behavior of the isolator system was studied. Many structures have non-rigid connections; the effect of this issue was considered in the pendulum column's performance in this paper. Its mathematical equations were derived, solved with MATLAB software, and compared with ABAQUS results. Later on, the isolator system was investigated during different earthquakes. The results show that this mechanism is suitable as an isolator. The period was found to be longer in the flexible pier form. The flexible piers have an influential role in the system's response by reducing the system's stiffness considerably. Among the different damping ratios, those with more than 15% had better results. Finally, the tested model verified the theory.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.499-505
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• 2007

The major effective of this study is to investigate the fatigue effects of rail pad on High Speed Railway with concrete slab track system. It analyzed the mechanical behaviors of HSR concrete slab track with applying rail pad stiffness based on fatigue effect (hardening and increasing stiffness) on the 3-dimensional FE analysis and laboratory test for static & dynamic characteristics. As a result, the hardening of rail pad due to fatigue loading condition are negative effect for the static & dynamic response of concrete stab track which is before act on fatigue effect. The analytical and experimental study are carried out to investigate rail pad on fatigue effected increase vertical acceleration and stress and decrease suitable deflection on slab track. And rail pad based on fatigue effect induced dynamic maximum stresses, the increase of damage of slab track is predicted by adopting fatigue effected rail pad. after due consideration. The servicing HSR concrete slab track with resilient track system has need of the reasonable determination after due consideration fatigue effect of rail pad stiffness which could be reducing the effect of static and dynamic behavior that degradation phenomenon of structure by an unusual response characteristic and a drop durability.