• Journal of Korea Trade
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• v.23 no.3
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• pp.68-83
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• 2019

Purpose - The UNCITRAL Model Law on Electronic Transferable Records (Model Law) is based on the principles of non-discrimination against the use of electronic means, functional equivalence, and technology neutrality underpinning all UNCITRAL texts on electronic commerce. Investigating the disagreements between the Model Law and the Koran Commercial Act (KC Act), including the B/L Regulation, and suggesting the revision of the KC Act including the B/L Regulation, could be a valuable study. The purpose of this paper is to contribute to the harmonization of Korean legislation regarding electronic bill of lading in compliance with the Model Law. Design/methodology - The Model Law is flexible to accommodate the use of all technologies and models, such as registries, tokens, and distributed ledgers: that is, blockchain. In 2007, the KC Act was revised to regulate electronic bills of lading to promote the widespread legal use of electronic bills of lading. In addition, The Regulation on Implementation of the Provisions of the Commercial Act Regarding Electronic Bills of Lading (the B/L Regulation) was enacted to regulate the detailed procedures in using electronic bills of lading in 2008. This paper employs a legal analysis by which this paper does find differences between two rules in light of technology neutrality and global standard of electronic bills of lading model. Findings - The main findings are as follows: i) the Korean registry agency has characteristics of a closed system. ii) The KC Act has no provision regarding control. iii) The KC Act discriminates other electronic bills of lading on the ground that it was issued or used abroad. Moreover, this study does comprehensive analysis of Korean Acts in comparison with the Model Law and, in particular, this study analyzes the differences between the KC Act and the Model Law by comparing article by article in view of the harmonization of the two rules. Originality/value - The subject of previous several studies was draft provisions on Electronic Transferable Records before completion of the Model Law; thus, these studies did not take into consideration the character of the Model Law as the Model Law was chosen at the final stage of legislation. This study is aimed at the final version of the Model Law. So, this study is meaningful by finding the suggestion and directions for the Korean government to revise the KC Act and the B/L Regulation in line with the Model Law.

• Journal of Power Electronics
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• v.16 no.4
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• pp.1324-1335
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• 2016

This article explores the speed regulation problem of permanent magnet synchronous motor (PMSM) systems subjected to unknown time-varying disturbances. A continuous sliding mode control (CSMC) technique is introduced for the speed loop to enhance the robustness of PMSM systems and eliminate the chattering phenomenon caused by high-frequency switch function in the conventional control law. However, the high control gain of the CSMC law in the presence of strong disturbances leads to large steady-state speed fluctuations for PMSM systems. In many application fields, PMSM systems are affected by time-varying disturbances instead of constant disturbances. For example, electric bicycles are usually affected by changing environmental disturbances, including wind speeds, road conditions, etc. These disturbances may be in the form of constant, ramp, and parabolic disturbances. Hence, a generalized proportional integral (GPI) observer is employed to estimate these types of disturbances. Then, the disturbance estimation method and the aforementioned CSMC method are combined to establish a composite sliding mode control method called the CSMC+GPI method for the speed loop of PMSM systems. Contrary to the conventional sliding mode control technique, the proposed method completely eliminates the chattering phenomenon caused by the switching function in the conventional control law. Moreover, a small control gain for the CSMC+GPI method is chosen by feed-forwarding estimated values to the speed controller. Hence, the steady-state speed fluctuations are small. The effectiveness of the proposed control scheme is verified by simulation and experimental result.

• Journal of Families and Better Life
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• v.14 no.4
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• pp.13-26
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• 1996

Based on the conceptual framework of Double ABCX model of family stress and adaptation this study developed the enrichment program for the relationship of young daughters-in-law with their mothers-in-law. Results of empirical research concerning the relationship between them also provided for the basis of designing this program. Consisting of 6 sessions this education program was delivered to 20 young daughters-in-law in a rural area of Kyunggi-do province. The effectiveness of the program was evaluated through one-group posttest design and follow-up interview. Overall most participants in the program reported that the relationship with their mothers-in-law was enhanced in terms of understanding mothers-in-laws psychology and roles of improving communication and problem-solving skills self-control and of blaming.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2001.06a
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• pp.105-108
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• 2001

In this paper, we proposed a variable structure controller with fuzzy PI-쇼pe reaching law. we fuzzified as inputs to fuzzy system Rf(representative point's orthogonal distance(rd) to switching surface and RP's distance(r) to the origin of the 2-dimensional space whose coordinates are the error and the error rate. The increments of the coefficients $k_{p}$ and $k_{i}$, of the reaching law are calculated appropriate by the simplified Mamdanl inference. The proposed fuzzy PI-type reaching law makes it reduce the chattering and has no need to tune the PI parameters of reaching law. The effectiveness of the proposed fuzzy PI-type reaching law is shown by the simulation results of the control of a Ball-balance System.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1309-1313
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• 2010

In this paper, we propose a novel guidance law for controlling an UAV(Unmanned Air-Vehicle) to follow a reference line in vertical plane. A kinematics model representing the relative motion of the UAV to the reference line is derived. And then LQR(Linear Quadratic Regulator) theory is applied to the model to derive the VLFG(Vertical Line Following Guidance) law. The resultant guidance law forms a gain-scheduling controller scheduled by a simple parameter $\sigma$ which is a function of the UAV's velocity, axial acceleration, gravity, and the slope of the reference line. Also derived is a stability condition for the $\sigma$ variation based on Lyapunov theory. Simulation results show that the proposed guidance law can be applied effectively to UAV guidance algorithm design.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.12-15
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• 1996

In this paper, a new shape control law is derived as a result of introducing the parametric curve representation. This control alw is based on the estimation of the curve parameters corresponding to the target joint positions and the target tip position. Estimating target curve parameters makes it possible to find, easily, a simple shape control law by the Lyapunov design method.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.1
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• pp.1147-1154
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• 2001

In this paper, a new iterative learning control scheme for discrete time nonlinear systems is proposed based on an objective function consisting of the output error and input energy. The relationships between the proposed ILC and the optimal control are described. A new input update law is proposed and its convergence is proved under certain conditions. In this proposed update law, the inputs in the whole control horizon are updated at once considered as one large vector. Some illustrative examples are given to show the effectiveness of the proposed method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.2
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• pp.357-364
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• 2002

A new chattering free sliding made control is proposed for robot manipulators. The control input is derived from the reaching law and the Lyapunov stability criteria, which is only composed of continuous terms. It has a chattering free characteristics and a concise farm. In implementing procedures, no change of equations is needed. Thus, it does not degrade the original merits of the sliding mode control. And it is applied to a 2-link SCARA robot manipulator. It is shown that the proposed control has good trajectory tracking performance compared with the PD control and the conventional sliding mode control which uses the boundary layer concept.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.12
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• pp.1070-1078
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• 2000

A nonlinear adaptive flight control system is proposed using a backstepping controller with neural network controller. The backstepping controller is used to stabilize all state variables simultaneously without the two-timescale assumption that separates the fast dynamics, involving the angular rates of the aircraft, from the slow dynamics which includes angle of attack, sideslip angle, and bank angle. It is assumed that the aerodynamic coefficients include uncertainty, and an adaptive controller based on neural networks is used to compensate for the effect of the aerodynamic modeling error. It is shown by the Lyapunov stability theorem that the tracking errors and the weights of neural networks exponentially converge to a compact set. Finally, nonlinear six-degree-of-freedom simulation results for an F-16 aircraft model are presented to demonstrate the effectiveness of the proposed control law.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.1
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• pp.99-107
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• 2017

In this work, the nutation control of rigid spacecraft with only two momentum wheels is addressed by applying the feedback linearization technique. In this strategy, the primary performance index is to regulate the nutational angle by the momentum control of wheels. The spacecraft attitude equations of motion are transformed to a general linearized form by feedback linearization technique, including a guaranteed control law promising the internal dynamics stability to accomplish the nutation angle small. It is proven that the configuration of inertia properties plays a key role in analyzing spacecraft energy level. The behavior of the momentum wheels is also studied analytically and numerically. Finally, the effectiveness of the proposed nonlinear control law for the momentum transfer is verified by conducting numerical simulations.