• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.2
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• pp.192-201
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• 2001

Analyzing internal structure, flow rate and dynamic behavior characteristics of electronically controlled shock absorber, damping performance limit is identified to comprise the two reciprocal characteristics of ride comfort and handling safety. Regardless of its lower performance than the active suspension control system, the semi-active suspension control system has been taking interest because of its absolutely higher performance than passive suspension system. Since the pervious studies have been concentrated mostly on analytic aspect and survey on the internal structure of the shock absorber remain insufficient, the main discourse of this paper is focused on analyzing the nonlinear shock absorber which varies the damping force of semi-active suspension system and the dynamic characteristics of the solenoid valve, a sort of pressure valve, and proposing the design factors of importance.

• Journal of Digital Convergence
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• v.19 no.2
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• pp.51-60
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• 2021

In this study, Based on the analysis of the correlation between internal control quality and earnings management, this article discusses the correlation between internal control quality and real activity earnings management and accrued earnings management. For this study, by introducing the concept, classification, measurement method and model of internal control and earnings management, the research hypothesis of this article was proposed. In this analysis, Use the relevant measurement model to calculate the actual activity earnings management level and accrued earnings management level of the enterprise, as the explained variable, establish a model for regression and were analyzed. Also, this study could find the final results draws a conclusion through empirical research: there is a significant negative correlation between the internal control quality of listed companies, real activity earnings management, and accrued earnings management. On the basis of this conclusion, the analysis of possible causes provides a basis for the development of internal control theory and the supervision and control of earnings management behavior in the future.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.755-759
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• 1989

This paper considers an active vibration control system based on pole placement incorporating the internal model principle when the system is subjected to disturbances which are generated by a linear dynamical system. Experimental results are presented which show the effectiveness of the method when the system is excited by a sine wave disturbance and system parameters are knwon. An adaptive control design is also discussed.

• Journal of the Korea Convergence Society
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• v.11 no.12
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• pp.243-251
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• 2020

The purpose of the study is to explore the relationship between the type of reporting weaknesses in the Internal Accounting Control System and executive compensation, and then analyze whether such relevance varies depending on the characteristics of governance structure. The analysis data used 6,343 KOSPI&KOSDAQ companies excluding the financial industry from 2011 to 2016. As a results of the study, First, executive compensation decreased in companies reporting the weaknesses of CL. Second, this relevance was further strengthened according to the governance structure. This study confirms that information on the operation results of system is an important factor in determining manager compensation. It implies that it is necessary to study reasonable compensation policies and governance structures suitable for companies. If an internal control system that affects executive compensation is added, the basis for stronger support of the research results can be prepared.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.341-347
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• 2012

Network Access Control system of medical asset protection solutions that installation and operation on system and network to provide a process that to access internal network after verifying the safety of information communication devices. However, there are still the internal medical-data leakage threats due to spoof of authorized devices and unauthorized using of users are away hours. In this paper, Network 2-Factor Access Control Model proposed for prevention the medical-data leakage by improving the current Network Access Control system. The proposed Network 2-Factor Access Control Model allowed to access the internal network only actual users located in specific place within the organization and used authorized devices. Therefore, the proposed model to provide a safety medical asset environment that protecting medical-data by blocking unauthorized access to the internal network and unnecessary internet access of authorized users and devices.

• Journal of Power System Engineering
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• v.13 no.6
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• pp.43-50
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• 2009

If an internal combustion engine is operated by consolidated control, the minimum fuel consumption is achieved satisfying the demanded objectives. For this, it is necessary that the engine is operated on the ideal operating line which satisfies minimum fuel consumption. In this context of view, there are many tries to achieve given object. However, the parameter in the internal combustion engines are variable and depend on the operating points. Therefore, it is necessary to cope with the uncertainties such that the optimal operating may be possible. From this point of view, this paper gives a controller design method and a robust stability condition for engine torque control which satisfies the given control performance and robust stability in the presence of physical parameter perturbation. Exactly, the present paper considers a robust stability of this 2DOF servosystem with nonlinear type uncertainty in the engine system, and a robust stability condition for the servosystem is introduced. This result guarantees that if the plant uncertainty is in the permissible set defined by the given condition then a gain tuning can be carried out to suppress the influence of the plant uncertainties.

• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.367-377
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• 2001

Objectives: We aimed to identify. the effect of Jeongcheon-tang(定喘湯) and Cheongsangboha-tang(淸上補下湯) on the transcriptional activities of cytokine IL-4, IL-5, IL-6 and IL-10 involved in asthma model. Materials and Methods: RBL-2H3 cell lines were used. Cells were stimulated with calcium inophore($2{\mu}M$ : Sample group 1, $4{\mu}M$ : Sample group 2) for maximal gene expression. After 3rd treatment of samples and incubation(per 24hours), total cellular RNAs were collected using Trizol solution method. Then transcriptional activities of IL-4, IL-5, IL-6 and IL-10 were measured by RT-PCR with electrophoresis. Results: In IL-4 study, Jeongcheon-tang treated group showed 82.76%(Sample group 1) of transcriptional activities compared to the control group and Cheongsangboha-tang treated groups showed 85.77% (Sample group 1), 89.42% (Sample group 2) of transcriptional activities compared to the control groups. In IL-5 study, Jeongcheon-tang treated groups showed 88.24%(Sample group 1), 98.83%(Sample group 2) of transcriptional activities compared to the control groups and Cheongsangboha-tang treated group showed 73.66%(Sample group 2) of transcriptional activities compared to the control group. In IL-6 study, Jeongcheon-tang treated group showed 92.95%(Sample group 2) of transcriptional activities compared to the control group and Cheongsangboha-tang treated group showed n.40%(Sample group 2) of transcriptional activities compared to the control group. In IL-10 study, Jeongcheon-tang treated group showed 118.46% (Sample group 2) of transcriptional activities compared to the control group. Conclusions: This study shows that Jeongcheon-tang has the inhibitory effect on the transcription of IL-4, IL-5, IL-6 gene expression and the increasing effect on the transcription of IL-10 gene expression, and Cheongsangboha-tang has the inhibitory effect on the transcription of IL4, IL-5 and IL-6 gene expression in RBL-2H3 cell lines. Advanced studies are required to investigate the mechanisms of inhibition or increase by herbal medicine in asthma model.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.5
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• pp.592-599
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• 1998

In this paper, we design a tracking controller which satisfies transient response specifications and maintains tracking error within a tolerable limit for the uncertain track-following system of an optical disk drive. To this end, a robust $H_{\infty}$ control problem with regional stability constraints and sinusoidal disturbance rejection is considered. The internal model principle is used for rejecting the sinusoidal disturbance caused by eccentric rotation of the disk. We show that a condition satisfying the regional stability constraints can be expressed in terms of a linear matrix inequality (LMI) using the Lyapunov theory and S-procedure. Finally, a tracking controller is obtained by solving an LMI optimization problem involving two linear matrix inequalities. The proposed controller design method is evaluated through an experiment.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.183-188
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• 2014

Solenoid operated electromagnetic control valve (ECV) using in an external variable displacement swash plate type compressor is widely used for air conditioning control system because of its low energy consumption and high efficient characteristics. ECV controls the entire vehicle air conditioning system by means of a pulse width modulation (PWM) system that supplied from an external controller. Different pressure ports located within ECV has important functions to control the air/refrigerant flow through its internal passages. The flow paths are preciously maintained with acceptable ranges of leakage (gap) between the parts inside it which is followed by effective design and critical dimensioning of its internal features. Therefore, it saves energy losses from the solenoid operation as well as ensures the balance of forces within it. The research paper highlights analysis of the leakages (at different pressure ports) and dimensioning tolerance factors that affects the ECV performance.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.4
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• pp.1088-1091
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• 2005

This study was designed to research whether Dinamika can yield a suitable diagnosis for Activity of Autonomic Nene System on stroke. The testing of Dinamika was carried out at Oriental Medical Centar of Dong-Eui University with the participation of 27 patients. The results of Dinamika examinations shows as follows : Group A(the rising of a parasympathetic nerve system) is 0 persons. And Group B(the balancing autonomic none system) is 4 persons. Group C(the rising of a sympathetic nerve system) is 23 persons. There are 7 persons that it is difference of more than $20\%$ between B1 (the control ability of autonomic nerve system) and B2(the potential energy to control autonomic nerve system), 11 person that B1 and B2 are less than $10\%$, 1 person that B1 and B2 are balanced about $60\%$, 8 person that it is balanced domain from $10\%\;to\; 60\%$ between B1 and B2. According to this study on activity of autonomic nerve system using Dinamika on Stroke, these results suggest that 27 patients evidence the problem of autonomic none systems.