• International Journal of Control, Automation, and Systems
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• v.6 no.4
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• pp.515-525
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• 2008

In this paper, the problem of delay-dependent stabilization for singular systems with multiple internal and external incommensurate constant point delays is investigated. The condition when a singular system subject to point delays is regular independent of time delays is given and it can be easily test with numerical or algebraic methods. Based on Lyapunov-Krasovskii functional approach and the descriptor integral-inequality lemma, a sufficient condition for delay-dependent stability is obtained. The main idea is to design multiple memoryless state feedback control laws such that the resulting closed-loop system is regular independent of time delays, impulse free, and asymptotically stable via solving a strict linear matrix inequality (LMI) problem. An explicit expression for the desired memoryless state feedback control laws is also given. Finally, a numerical example illustrates the effectiveness and the availability for the proposed method.

• International Journal of Safety
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• v.5 no.2
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• pp.6-11
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• 2006

The time delay in servo control on LonWorks/IP Virtual Device Network (VDN) is highly stochastic in nature. LonWorks/IP VDN induced time delay deteriorates the performance and stability of the real-time distributed control system and hinders an effective preventive and predictive maintenance. Especially in real-time distributed servo applications on the factory floor, timely response is essential for predictive and preventive maintenance. In order to guarantee the stability and performance of the system for effective preventive and predictive maintenance, LonWorks/IP VDN induced time delay needs to be predicted and compensated for. In this paper position control simulation of DC servo motor using Zero Phase Error Tracking Controller (ZPETC) as a feedforward controller, and Internal Model Controllers (IMC) based on Smith predictor with disturbance observer as a feedback controller is performed. The validity of the proposed control scheme is demonstrated by comparing the IMC based on Smith predictor with disturbance observer.

• The Journal of Internal Korean Medicine
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• v.26 no.1
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• pp.156-168
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• 2005

Objective : The purpose of this research is to examine the effects of Pinelliae Rhizoma (PR) extract on immune cells and cytokines in ovalbumin (OVA)-induced asthmatic mice. Methods : In vivo, C57BL/6 mice were sensitized and handicapped by OVA for 12 weeks. During this experiment, the one group was then treated with PR extract for the 8 weeks (3 times per week) and analyzed by ELISA and flow cytometer. Results : In vivo, there were significant decreases in eosinophils, IL-4, IL-5, IL-13, IgE in BALF (bronchoalveolar lavage fluid) compared with that of control group. However, $IFN-{\gamma}$ in BALF of GS group increased significantly, compared with that of control group. Additionally, the population of $CD3e^-/CCR3^+,\;CD69^+/CD3e^+,\;IgE^+/B220^+,\;CD11b^+/Gr-l^+$ cells in the PR group decreased, compared with that of control group. Conclusion : The results of this study support a role for PR as an effective treatment for asthma in its experimental success in significantly decreasing inflammation and asthma reactions, and in increasing $IFN-{\gamma}$, which helps prevent such reactions.

• Journal of Power System Engineering
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• v.18 no.1
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• pp.7-13
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• 2014

• Computational Structural Engineering
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• v.9 no.3
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• pp.125-134
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• 1996

The base-isolation of building, as appeared in many studies, has shown remarkable performance in seismic response attenuation of the internal system as well as the building structure itself. But for the case that the internal system is submerged and hence subject to a considerable hydrodynamic effect, the seismic response of the system due to the base-isolation of building can be greater than the case that they are in air. This paper presents the dynamic analysis of a submerged internal system on base-isolated building to show such an example. The results show that an additional treatment is required to reduce the adverse effects on the seismic response of such a system when the building is base-isolated, and that the system response can be reduced to some extent by an appropriate control of fluid gap between the system and the building structure.

• Journal of Oriental Neuropsychiatry
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• v.20 no.4
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• pp.127-135
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• 2009

Objectives : This study was conducted to assess the effect of Chunwangbosim-dan(CB) on the autonomic nervous system by using heart rate variability measurement. Methods : The eligible subjects were composed of the healthy female group of ages 25 to 30 years. They were divided into two groups, the CB group(n=16) and the control group(n=16). We measured the heart rate variability respectively for 3 times at 14:00, 16:00, and 17:00. In the CB group, subjects were administered CB at 15:00. For the measurement values, Mean Heart Rate and SDNN(standard deviation of the NN intervals) were used as time domain analysis, and HF(high frequency), LF(low frequency), and LF / HF ratio were used as frequency domain analysis. Results : The degree of LF changes in the CB group was significantly lower than control group at 1 hour after administration. Conclusions : We suggest that Chunwangbosim-dan may be useful for stabilization of the autonomic nervous system by controlling sympathetic nerve in healthy people.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.142-147
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• 1988

Free-path-type guidance system does not need a hardwired path in the environment so that it gives a mobile robot a flexible path. ln this study to achieve the free-path-type guidance system for a mobile robot which is steered by the differential steering of both drive forewheels, position recognition systems are constructed using odometer system as an internal position sensor. Two odometer systems, a auxiliary wheel odometer and a 2-encoder odometer system are constructed and path following algorithms using these odometer systems are designed and experimented. PID control type is adopted in the path following algorithms.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1353-1360
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• 2009

This study examines the effects of internal control system and Analysis of characteristics and Earning management in Vulnerable Cooperation. During research period 2005${\sim}$2007, Purpose of this study is to examines whether financial characteristics has exist or not. Second, Earning management also. As a result of analysis are as follows, First T-test and logistic regression has found explanatory with stastical significance about CURRENT, RNPS, and DEPT. Second, DA of Vulnerable Cooperation is significantly higher than Normal cooperation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.6
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• pp.313-320
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• 2015

In this paper, a method to obtain the probability distribution of room temperature and cooling load is presented, when the internal heat generation is applied to the system as a disturbance in the air conditioning system with slab cooling storage. The probability distribution of room temperature and the cooling load due to the disturbance were examined in one room of an office building. When considering only the electric power consumption as a probability component, it was found that the effect on room temperature and cooling load is small, because the probability component of the measured electric power consumption in the building is small. On the other hand, when considering the stochastic fluctuations of electric power consumption together with the heat generated by human bodies, the mean value of the cooling load was about 2,300 W and the ratio of the standard deviations was 19% (10 o'clock in second day). It was revealed that the stochastic effects of internal heat generation acting on the air conditioning system with slab cooling storage are not small.

• Transactions on Control, Automation and Systems Engineering
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• v.4 no.1
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• pp.2-8
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• 2002

This paper discusses haptic display for grasping a virtual object by two fingers. Much research has been done on fundamental analysis for stability of haptic display. But it is difficult to apply the results immediately to grasping situations by two fingers, since the studies usually deal with a single device and a single object and the fingertip force in grasping situations has two components, internal and external components. The conventional methods, which specify the coupling impedance at each contact point separately, have no other alternative but to specify the impedance for the sum of the internal and external components. So even if only the impedance for the external force should be changed, the impedance for the internal force is also changed at the same time. In this paper, a new method, in which the coupling impedance is specified separately for the internal and external forces, is proposed and the stability of the proposed method is discussed using passivity analysis for 1 -DOF(Degree-Of-Freedom) system. Finally, some experiments are performed to study the effects of the proposed method.