• International Journal of Control, Automation, and Systems
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• v.6 no.2
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• pp.186-193
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• 2008

The Internet's low cost and ubiquity present an attractive option for real-time distributed control of processes on the factory floor. When integrated with the Internet, the LonWorks open control network can give ubiquitous accessibility with the distributed control nature of information on the factory floor. One of the most important points in real-time distributed control of processes is timely response. There are many processes on the factory floor that require timely response. However, the uncertain time delay inherent in the network makes it difficult to guarantee timely response in many cases. Especially, the transmission characteristics of the LonWorks/IP network show a highly stochastic nature. Therefore, the time delay problem has to be resolved to achieve high performance and quality of the real-time distributed control of the process in the LonWorks/IP Virtual Device Network (VDN). It should be properly predicted and compensated. In this paper, a new distributed control scheme that can compensate for the effects of the time delay in the network is proposed. It is based on the PID controller augmented with the Smith predictor and disturbance observer. Designing methods for output feedback filter and disturbance observer are also proposed. Tracking position control experiment of a geared DC Servo motor is performed using the proposed control method. The performance of the proposed controller is compared with that of the Internal Model Controller (IMC) with the Smith predictor. The result shows that the performance is improved and guaranteed by augmenting a PID controller with both the Smith predictor and disturbance observer under the stochastic time delay in the LonWorks/IP VDN.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.467-470
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• 2004

MANPro-based control is a novel control paradigm aimed at intelligent manufacturing systems on the basis of mobile agent-based negotiation process (MANPro). MANPro is a negotiation mechanism based on the agent-based control architecture and, especially, it adapts a mobile agent system called N-agent for the negotiation process. N-agent travels around the network of distributed manufacturing systems to acquire information, and it makes a decision for system control according to the obtained information. MANPro includes communication architecture and information architecture for intelligent shop floor control. MANPro also considers the following issues: (1) negotiation mechanism, (2) single-agent internal strategic policies, and (3) information model. Communication architecture concerns the first issue of the negotiation mechanism. It provides information exchanging mechanism with functional modules. In specific, N-agent is equipped with an intelligent reasoning engine with a built-in knowledge base. This reasoning engine is closely related to the single-agent internal strategic policies of the second issue. Finally, ontology-based information architecture addresses information models and provides a framework for information modeling on negotiation. In this paper, these three issues are addressed in detail and a framework of MANPro-based control is also proposed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.1
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• pp.35-41
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• 2010

In developing modern aircraft, the reconfiguration control that can improve the safety and the survivability against the unexpected failure by partitioning control surfaces into several parts has been actively studied. This paper deals with the reconfiguration control using model predictive control method considering the saturation of control surfaces under the control surface failure. Linearized aircraft model at trim condition is used as the internal model of model predictive control. We propose the controller that performs optimization using LMI (linear matrix inequalities) based semi-definite programming in case that control surface saturation occurs, otherwise, uses analytic solution of the model predictive control. The performance of the proposed control method is evaluated by nonlinear simulation under the flight scenario of control surface failure.

• Korean Journal of Acupuncture
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• v.24 no.4
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• pp.163-180
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• 2007

Objective : Oriental medicines have been applied to Membranous nephropathy(MN) for the purpose on increasing renal blood flow and modulating immune activity in according to Oriental medicine theories. Magsungsinyeom-bang (MSSYB) is one of the prescription which is known to show positive results in clinic with lack of laboratorial evidence. Thus, this study was aimed to evaluate the effects of MSSYB and partially investigate the mechanisms of it. Methods : The effect of MSSYB was evaluated by the morphology for the GBM thickening, protein excretion in urine and biochemical parameters in serum using cBSA-induced MN mice model. Mice were administered with MSSYB(250 or 500 mg/kg) or PBS for control group from experimental week 3 for 4 weeks. Results : 24 hrs proteinuria and the concentrations BUN was significantly decreased in the MS groups compared to the control group while the concentrations of serum albumin was higher in the MS groups than control group. MSSYB didn't affect the ratio of CD3e+/CD or 19CD4+/CD8 in the spleen and kidney, but inhibit the expression of IL-1${\beta}$, TNF-${\alpha}$, IL-6, and production of IgG and IgM. In histological analysis of kidney tissue, thickening of GBM was significantly decreased in the MS group compared to control group. Conclusions : MSSYB showed the positive results on the cBSA-induced membranous nephropathy in mice, thus, it could be a useful candidate for oriental drug for treating the membranous nephropathy in clinic.

• Journal of Power System Engineering
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• v.17 no.3
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• pp.82-88
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• 2013

For commercialized servo drives of the motion stage to include embedded controller, external terminal is provided for tracking command and encoder output, but internal terminal is not for control input. Thus, it is difficult to combine out signal of embedded controller with that of external compensator such as disturbance observer. In this study, for precise tracking control of motion stage without hardware change of the servo drive, tacking control system is composed of an inner loop of servo drive and an outer loop of disturbance observer. Then, the control system is designed so that the output response of actual plant corresponds with nominal model's in transient state as well as in steady state. Finally, the experiment results show that the designed control system is effective to reconcile actual plant behavior with nominal model under nonlinear friction and parameter perturbation.

• New & Renewable Energy
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• v.4 no.4
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• pp.65-71
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• 2008

Considering the world's environmental problem, HEVs are projected as one of the solution. The keys of the HEV cruise control are expanding the use of electric motor and operating the internal combustion engine in the efficient region. This paper presents a new structure of SOC sustaining model where state-machine control is used. The proposed model defines battery charging and discharging as states and SOC of the battery as control variables. In this paper, we introduce various methods in deterministic rule-based control for HEV and describe a new SOC sustaining controller used by state-machine.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.7
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• pp.113-121
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• 2005

In this paper, a constant output power supply system for ozonizer is proposed to remove the noise of ozonizer and control the output of ozonizer using feedback control. The proposed system is based on the rouble control loop such as the outer voltage control loop and inner current control loop. In the proposed system overshoots and oscillations due to the computation time-delay are compensated by explicit incorporation of the time-delay in the current control loop transfer function. The inner current control loop is adopted by an internal model controller. The internal model controller is designed to a second order deadbeat reference-to-output response which means that its response reaches the reference in two sampling time including computational time-delays. The outer voltage control loop employing P-Resonance controller is proposed. The resonance controller has an infinite gain at resonant frequency, and the resonant frequency is set to the fundamental frequency of the reference voltage in this paper. Thus the outer voltage control loop causes no steady state error as regard to both magnitude and phase. The effectiveness of the proposed control system has been verified by the experimental results.

• The Journal of Internal Korean Medicine
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• v.37 no.3
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• pp.467-483
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• 2016

Objective: This study was performed to investigate the effect of IUS (Inulsan, an extract of Artemisiae capillaris (茵蔯), Curcumae longae (鬱金), and Crataegi fructus (山査)) on anti-hyperlipidemia, anti-oxidation, and anti-inflammation.Method: We administered water extracts of Artemisiae capillaris, Curcumae longae, and Crataegi fructus for three weeks to db/db mice (C57BL/Ks), animal models induced with type 2 diabetes mellitus. Mice were divided into three groups: normal (C57BL/6J mice group), control group (db/db mice without administration of IUS) and IUS group (db/db mice treated with IUS). Then we measured total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride in the serum after the oral administration of IUS.Results: 1. IUS did not show any cytotoxicity in RAW 264.7 cells. 2. IUS decreased AST, ALP, and creatinine levelsand did not show any liver or renal toxicity in the db/db mice. 3. IUS increased DPPH and ABTS radical scavenging activity and decreased ROS production in RAW 264.7 cells. 4. IUS significantly decreased IL-1β, IL-6, and TNF-α production in RAW 264.7 cells. 5. IUS increased HDL cholesterol and significantly decreased total cholesterol and triglyceride in db/db mice. 6. IUS significantly decreased the atherogenic index and cardiac risk factor. 7. In contrast with the control group, fat infiltration in the liver and aorta decreased in IUS treated mice. The cell nucleus was located in the central area in H&E staining of liver. And endomembranes also were more thinner than the control group in H&E staining of aorta.Conclusions: These results suggest that IUS might be effective in the prevention and treatment of dyslipidemia.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.1
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• pp.18-24
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• 2015

In this study, a $CO_2$ air-conditioning system was investigated with different types of electrically driven compressors, parallel flow type gas cooler, four-pass type evaporator, internal heat exchanger integrated with accumulator, and electric expansion valve. The experimental study was conducted under various operating conditions (ie., different rotational compressor speeds, air inlet temperatures and air velocity coming into heat exchangers). The experimental results showed the cooling capacity was 3.5kW at $35^{\circ}C$ ambient temperature when the vehicle was idle (ie., the worst condition for cooling off the gas cooler). In terms of performance effect of the compressor, the e-RP model had a slightly better cooling capacity and coefficient of performance than the e-GR model under the same test conditions. An experimental equation for optimum cooling-performance control was also suggested based on the results. A high-pressure control algorithm for the super critical cycle was determined to achieve both maximum cooling performance and efficient energy consumption. The results from the experimental equation coincided with those of previous experimental studies.

• The Journal of Internal Korean Medicine
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• v.40 no.4
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• pp.567-581
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• 2019

Objective: This study aimed to evaluate the inhibitory effects of SGX01 on the lung injuries of COPD mice model. Materials and Methods: This study was carried out in two ways: in vitro and in vivo. In vitro, L929 cells were challenged with LPS, and then treated with six concentrations of SGX01 (10, 30, 50, 100, 300, and $500{\mu}g/ml$) and analyzed by ELISA. In vivo, C57BL/6 mice were challenged with LPS and cigarette smoking solution (CSS), and then treated with a vehicle only (control group), dexamethasone 3 mg/kg (dexa group), or a SGX01 200 mg/kg (SGX01 group). After sacrifice, the BALF or lung tissue was analyzed with Cytospin, FACS, ELISA, real-time PCR and H&E, and Masson's trichrome staining. Results: SGX01 significantly decreased NO, $TNF-{\alpha}$, and IL-6 on L929 cells challenged with LPS. In the COPD model, SGX01 significantly inhibited the increase of neutrophils, $TNF-{\alpha}$, IL-17A, CXCL-1, MIP2, CD8+ cells in BALF, and $TNF-{\alpha}$, $IL-1{\beta}$ mRNA expression in lung tissue. It also decreased the severity of the histological lung injury. Conclusion: This study suggests the usability of SGX01 for COPD patients by controlling lung tissue injury.