• Proceedings of the KIPE Conference
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• 2001.12a
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• pp.79-82
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• 2001

New electronic ballast for metal halide laws is proposed New ballast has higher efficiency than that of conventional ballast. Proposed 2 stage ballast uses low arm switch as synchronous rectifier mitch. Switch-on voltage drop is smaller than that of diode in small current(<1.5A). High arm switch is turned on in zero voltage in proposed ballast. So conduction loss and switching loss are reduced Index word - synchronous rectifier mitch, toro voltage switching, conduction loss, switching loss.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.101-106
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• 2007

Noise pollution from a high speed train has been a serious social issue nowadays. Especially when a train speed exceeds 300km/hr, an aerodynamic noise level has been known to be increased based on 4-6th power laws. In this paper, a simple approach to evaluate the sensitivity effect on noise due to the speed change has been examination.

• Journal of Power Electronics
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• v.17 no.3
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• pp.766-776
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• 2017

In modern power systems, high penetration of distributed generators (DGs) results in high stress on system stability. Apart from the intermittent nature of DGs, most DGs do not contribute inertia or damping to systems. As a result, a new control method named virtual synchronous machine (VSM) was proposed, which brought new characteristics to inverters such as synchronous machines (SMs). In addition, different active power droop controls for VSMs are being proposed in literatures. However, they are quite different in terms of their dynamic characteristics despite of the similar control laws. In this paper, mathematical models of a VSM adopting different active power droop controls are built and analyzed. The dynamic performance of the VSM output active power and virtual rotor angular frequency are presented for different models. The influences of the damping factor and droop coefficient on the VSM dynamic behaviors are also investigated in detail. Finally, the theoretical analysis is verified by simulations and experimental results.

• Journal of Korean Academy of Nursing Administration
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• v.19 no.4
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• pp.513-524
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• 2013

Purpose: This study was conducted to identify ethical climate factors in hospitals and analyze their influence on job satisfaction and organizational commitment. Methods: A convenience sample of 196 nurses from one national university hospital in J city participated in this descriptive study survey. Instruments included the Ethical Climate Questionnaire, Job Satisfaction Scale, and Organizational Commitment Scale. Cronbach's ${\alpha}$ and factor analysis were done to test reliability and construct validity of the scales. Data were collected from March 15 to March 25, 2013 and analyzed using descriptive statistics, one-way ANOVA, t-test, Pearson correlation, and multiple regression with SPSS/WIN 18.0. Results: Seven ethical climate factors were identified; laws and professional codes, social responsibility, company rules and procedures, self-interest, personal morality, efficiency, and friendship. Factors influencing job satisfaction were friendship (${\beta}$=.25), social responsibility (${\beta}$=.20), laws and professional codes (${\beta}$=.20), and educational level (${\beta}$=.27), explaining 37.6% of variance in job satisfaction. Factors influencing organizational commitment included social responsibility (${\beta}$=.29), friendship (${\beta}$=.27), laws and professional codes (${\beta}$=.23), and age (${\beta}$=.19), with explanatory power of 44.6%. Conclusion: Results can be used as preliminary data for developing new strategies to establish positive ethical climates in hospital environments and thus enhance nurses' job satisfaction and organizational commitment.

• Journal of Arbitration Studies
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• v.13 no.2
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• pp.459-488
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• 2004

General interest in the out-of-court dispute resolution system are mounting in Korea, and the spread of ADR(alternative dispute resolution) is the worldwide trend. In addition, it was confirmed that the resolution of disputes by ADR such as the decision based on arbitration made by the Prime Ministerial Administrative Decision Committee is no longer in exclusive possession of the civil case. The activation of ADR could lead to the smooth agreement between parties by getting away from the once-for-all mode of decision such as the dismissal of the application or the cancellation of disposal and the like in relation to administrative cases for the years. In consequence, it is anticipated that the administrative litigation that applicants have filed by not responding to the administrative decision would greatly reduce in the future. But, it would be urgent to provide for the legal ground of the ADR system through the revision of related laws to take root in our society because ADR has no legal binding power relating to the administrative case due to the absence of its legal grounds. The fundamental reason for having hesitated to introduce ADR in relation to the administrative case for the years is the protective interest of the third party as well as the public interest that would follow in case the agreement on the dispute resolution between parties brings the dispute to a termination in the domain of the public law. The disputes related to the contract based on the public law and the like that take on a judicial character as the administrative act have been settled within the province of ADR by applying the current laws such as the Civil Arbitration Law, Mediation Law, but their application to the administrative act of the administrative agency that takes on a character of the public law has been hesitated. But as discussed earlier, there are laws and regulations that has the obscure distinction between public and private laws. But there is no significant advantage in relation to the distinction between public and private laws. To supplement and cure these defects it is necessary to include the institutional arrangement for protection of the rights and benefits of the third party, for example the provision of the imposition of the binding power on the result of ADR between parties, in enacting its related law. It can be said that the right reorganization of the out-of-court dispute resolution system in relation to the administrative case corresponds with the ideology of public administration for cooperaton in the Administrative Law. It is high time to discuss within what realm the out-of-court dispute resolution system, alternative dispute resolution system, can be accepted and what binding power is imposed on its result, not whether it is entirely introduced into the administrative case. It is thought that the current Civil Mediation Law or Arbitration Law provides the possibility of applying arbitration or mediation only to the civil case, thereby opening the possibility of arbitration in the field of the intellectual property right law. For instance, the act of the state is not required in establishing the rights related to the secret of business or copyrights. Nevertheless, the disputes arising from or in connection with the intellectual property rights law is seen as the administrative case, and they are excluded from the object of arbitration or mediation, which is thought to be improper. This is not an argument for unconditionally importing ADR into the resolution of administrative cases. Most of the Korean people are aware that the administrative litigation system is of paramount importance as the legal relief for administrative cases. Seeing that there is an independent administrative decision system based on the Administrative Decision Law other than administrative litigation in relation to administrative cases, the first and foremost task is the necessity for the shift in thinking of people, followed by consideration of the plan for relief of the rights through the improvement of the administrative decision system. Then, it is necessary to formulate the plan for the formal introduction and activation of ADR. In this process, energetic efforts should be devoted to introducing diverse forms of ADR procedures such as settlement conference, case evaluation, mini-trial, summary jury trial, early neutral evaluation adopted in the US as the method of dispute resolution other than compromise, conciliation, arbitration and mediation

• International Journal of Aeronautical and Space Sciences
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• v.15 no.1
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• pp.1-19
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• 2014

Attaching a piezoelectric transducer to a vibrating structure, and shunting it with an electric circuit, gives rise to different passive, semi-passive, and semi-active control techniques. This paper attempts to review the research related to structural vibration control, via passive, semi-passive, and semi-active control methods. First, the existing electromechanical modeling is reviewed, along with the modeling methods. These range from lumped parameters, to distributed parameters modeling of piezostructural systems shunted by electrical networks. Vibration control laws are then discussed, covering passive, semi-passive, and semi-active control techniques, which are classified according to whether external power is supplied to the piezoelectric transducers, or not. Emphasis is placed on recent articles covering semi-passive and semi-active control techniques, based upon switched shunt circuits. This review provides the necessary background material for researchers interested in the growing field of vibration damping and control, via shunted piezostructural systems.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.30
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• pp.91-120
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• 2006

An Arbitration agreement is one kind of contracts between two or more contracting parties; any possible disputes that arise concerning a contract will be settled by arbitration. Contracting parties who have made a valid arbitration agreement will submit a dispute for settlement to private persons(arbitrators) instead of to a court. Arbitration may depend upon the agreement of the private parties, but it is also a system which has been built on the law and which relies upon that law in order to make it effective both nationally and internationally. That is to say, arbitration is wholly dependent on the underlying support of the court. The complementarity of the courts and of the arbitrators is a well-established fact; they seek for the common purpose, the efficacy of international commercial arbitration. Most states' laws contain the provisions which have been set for the supportive role of the courts relating to arbitration; (1) the enforcement of the arbitration agreement(rulings on validity of the arbitration agreement), and the establishment of the tribunal at the beginning of the arbitration, (2) challenge of arbitrators, interim measures, and intervention during evidence in the middle of the arbitral proceedings, (3) filing of the award, challenge of the arbitral award, and recognition and enforcement of the arbitral award at the end of the arbitration. Most international instruments and national laws concerning arbitration believe that authoritative courts should play their power not to control and supervise arbitration but to support and develop the merits of arbitration at most. 1985 UNCITRAL Model Law also expressly limit the scope of court's intervention to assist arbitration, not to control it.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.301-304
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• 2016

Cyber world constitute the infrastructure of the country and its people and control. Cyber attacks and leakage of personal information are being threatened damage to the national economy and national security. December 2014 had been cyber hacking attacks on Korea Hydro & Nuclear Power Nuclear cooling system design drawings of a spill, and Cheong Wa Dae website hacked, KBS stations occurred in cyber hacking accidents. As a result, ICT-based Protection Act, Promotion of Information and Communications Network Utilization and Information Act on Protection, etc., privacy laws are being enforced, personal information in the form of requirements from leading high-tech eoryeowoona is to prevent the attacks of armed hackers Internet information society It proposes positive measures to keep your personal information officer and laws.

• Structural Engineering and Mechanics
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• v.85 no.2
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• pp.233-246
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• 2023

Bending and buckling analysis of multi-directional porous functionally graded sandwich plate has been performed for two cases namely: FG skin with homogeneous core and FG core with homogeneous skin. The principle of virtual displacements was employed and the solution was obtained using Navier's technique. This theory imposes traction-free boundary conditions on the surfaces and does not require shear correction factors. The validation of the present study has been performed with those available in the literature. The composition of metal-ceramic-based FGM changes in longitudinal and transverse directions according to the power law. Different porosity laws, such as uniform distribution, unevenly and logarithmically uneven distributions were used to mimic the imperfections in the functionally graded material that were introduced during the fabrication process. Several sandwich plates schemes were studied based on the plate's symmetry and the thickness of each layer. The effects of grading parameters and porosity laws on the bending and buckling of sandwich plates were examined.

• Journal of Drive and Control
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• v.19 no.1
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• pp.51-61
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• 2022

This paper presents a model-free system based on a framework of a backstepping sliding mode control (BSMC) with a radial basis function neural network (RBFNN) and adaptive mechanism for electro-hydraulic systems (EHSs). First, an EHS mathematical model was dedicatedly derived to understand the system behavior. Based on the system structure, BSMC was employed to satisfy the output performance. Due to the highly nonlinear characteristics and the presence of parametric uncertainties, a model-free approximator based on an RBFNN was developed to compensate for the EHS dynamics, thus addressing the difficulty in the requirement of system information. Adaptive laws based on the actor-critic neural network (ACNN) were implemented to suppress the existing error in the approximation and satisfy system qualification. The stability of the closed-loop system was theoretically proven by the Lyapunov function. To evaluate the effectiveness of the proposed algorithm, proportional-integrated-derivative (PID) and improved PID with ACNN (ACPID), which are considered two complete model-free methods, and adaptive backstepping sliding mode control, considered an ideal model-based method with the same adaptive laws, were used as two benchmark control strategies in a comparative simulation. The simulated results validated the superiority of the proposed algorithm in achieving nearly the same performance as the ideal adaptive BSMC.