• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.47
• /
• pp.157-182
• /
• 2010

A counter-guarantee is an independent undertaking and it functions in the same way as an ordinary independent guarantee. However, the typical notion of independence which applies to the relationship between the guarantee and the underlying contract cannot be exactly transposed to the relationship between the counter-guarantee and the primary guarantee, because the primary guarantor bears its duties that derive from the mandate. In this respect, this study reviews, with some critics, a Korean appellate court's decision and argues that, in spite of the principle of independence between the counter-guarantee and the primary guarantee, the primary guarantor may not be entitled to reimbursement from the counter-guarantor, if it is objectively evident that the primary guarantor has failed to perform its duty of verifying compliance under the primary guarantor or if it is objectively evident that the primary guarantor knows that it is objectively evident that there was fraudulent calling by the beneficiary under the primary guarantee.

• International Journal of Control, Automation, and Systems
• /
• v.5 no.6
• /
• pp.621-629
• /
• 2007

In the adaptive fuzzy control field for affine nonlinear systems, there are two basic configurations: direct and indirect. It is well known that the direct configuration needs more restrictions on the control gain than the indirect configuration. In general, these restrictions are difficult to check in practice where mathematical models of plant are not available. In this paper, using a simple extension of the universal approximation theorem, we show that the only required constraint on the control gain is that its sign is known. The Lyapunov synthesis approach is used to guarantee the stability and convergence of the closed loop system. Finally, examples of an inverted pendulum and a magnet levitation system demonstrate the theoretical results.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.5 no.2
• /
• pp.145-150
• /
• 2005

We proposed the indirect adaptive fuzzy model based sliding mode controller to control nonaffine nonlinear systems. Takagi-Sugano fuzzy system is used to represent the nonaffine nonlinear system and then inverted to design the controller at each sampling time. Also sliding mode component is employed to eliminate the effects of disturbances, while a fuzzy model component equipped with an adaptation mechanism reduces modeling uncertainties by approximating model uncertainties. The proposed controller and adaptive laws guarantee that the closed-loop system is stable in the sense of Lyapunov and the output tracks a desired trajectory asymptotically.

• Transactions on Control, Automation and Systems Engineering
• /
• v.3 no.1
• /
• pp.32-42
• /
• 2001

In this paper, a parameter estimator is developed for the plant model whose structure is represented by the Takagi-Sugeno model. The essential idea behind the on-line estimation is the comparison of the measured stated with the state of an estimation model whose structure is the same as that of the parameterized model. Based on the parameter estimation scheme, and indirect Model Reference Adaptive Fuzzy control(MRAFC) scheme is proposed to provide asymptotic tracking of a reference signal for the systems with uncertain for slowly time-varying parameters. The developed control law and adaptive law guarantee the boundedness of all signals in the closed-loop systems. In addition, the plant state tracks the state of the reference model asymptotically with time for any bounded reference input signal.

• Proceedings of the KIEE Conference
• /
• 1996.07b
• /
• pp.1037-1041
• /
• 1996

Input-output linearization technique in nonlinear control does not guarantee the robustness in the presence of parameter uncertainty or unmodeled dynamics, etc. However, it has been used as an important preliminary step in achieving additional control objectives, for instance, robustness to parameter uncertainty and disturbance attenuation. An indirect adaptive control scheme based on input-output linearization is proposed in this paper. The scheme consists of a Hopfield network for process parameter identification and an adaptive sliding mode controller based on input-output linearization, which steers the system response into a desired configuration. A numerical example is presented for the trajectory tracking of uncertain nonlinear dynamic systems with slowly time-varying parameters.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.20 no.1
• /
• pp.25-32
• /
• 2017

Most of weapon systems use aided navigation system which integrates inertial navigation and aiding sensors to compensate the INS errors increasing with the passage of time. Various aid sensors can be applied such as Global Navigation Satellite System (GNSS), radar, barometer, etc., but there might exist time delay caused by signal processing or transferring aid information. This time delay leads out-of-sequence measurements (OOSM) systems. Previously, optimal and suboptimal measurment update method for OOSM systems, where the time delay length are known, are proposed. However, previous algorithm does not guarantee the positive definite property of covariance matrix. In order to improve numerical stability for aided navigation using delayed-measurement, this paper proposes a new measurement covariance update algorithm be similar to Joseph-form in Kalman filter. Futhermore, we propose how to implement it in indirect feedback Kalman filter structure, which is commonly used in aided navigation systems, for time-delayed measurement systems. Simulation and vehicle test results show effectiveness of a proposed algorithm.

• International Commerce and Information Review
• /
• v.14 no.4
• /
• pp.339-360
• /
• 2012

We have more risks in international trade market than in the domestic business market because economic activities are going on with business transactions in different countries. K-sure's Refund Guarantee System is the most important system for Korean Small and Middle Shipbuilding Industries' business, but Korean exporters of Shipbuilding Industries are more interested in export financing through K-sure rather than its financial supporting services. The export insurance becomes more important service for international trade business and it its count as the only one indirect way of supporting export business because export insurance is accepted internationally under the WTO system. Also, it is the only measure that can cover emergency risk, credit risk, exchange risk which cannot be covered by private insurance. As the major risk manager for Korean exporters, the K-sure needs to provide an integrated risk management service for customers. Korean exporters can take more challenges in ever competitive international trade market and we can witness promotion of export in the future which is essential to Korea's economic growth.

• The Journal of the Korea Contents Association
• /
• v.20 no.11
• /
• pp.281-291
• /
• 2020

This study used Gauss-Poisson jump diffusion process on standard assets to estimate the statutory reserves of Variable Annuity (VA) guarantees specified in Korean bylaw of insurance supervision and calculated guarantee fees and risks based on the model to see the effect of considering the jumps. Financial assets, except KOSPI 200, have fat-tailed return distributions, which is an indirect evidence of discontinuous jumps. In the case of a domestic stock index and foreign stock indexes(Korean Won), guarantee fees and risks decrease when jumps are considered in models of underlying assets. This is explained by decreases in standard deviations after the jump diffusion is considered. On the other hand, in the case of domestic bond indexes and a foreign bond index(Korean Won), guarantee fees and risks tend to increase when jumps are considered. Results from a foreign stock index(US Dollar) and a foreign bond index(US Dollar) were opposite to those from the same kinds of Korean Won indexes. We conclude that VA guarantee fees and risks may be under or over estimated when jumps are not considered in models of underlying assets.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.1810-1815
• /
• 2011

Although the effectiveness of an express train's service is measured in "Total System Time or Cost" units, many cases had used indirect method what based on the distintion by number of passengers in a station or experiential knowledgements. These methods are not guarantee itself as an optimal strategy. Focusing "Total System Time or Cost" directly, this paper investigates the express train service's stop scheduling based on each OD-volume and trip time which mainly affect system time and cost. To do this, we built an IP model which has a binary set presenting express train's stop scheduling as decision variable and suggest a Genetic Algorithm (GA) to find heuristic optimal solution.

• Journal of the Korean Society of Safety
• /
• v.29 no.6
• /
• pp.1-8
• /
• 2014

Safety certification and inspection of dangerous machines and equipments used in industries are to save lives of workers and properties involved. Cause analysis of industrial accidents is essential to prove the effectiveness of such certification and inspection. This study focuses on suggesting systematic method for cause analysis of industrial accidents associated with dangerous machines and devices. Incorporating transition from the current user-oriented indirect regulations to more manufacturer and user balanced direct regulations, suggested method coupled with safety certification, safety inspection, safety management and safety education will guarantee more effective prevention of industrial accidents.