• 무역상무연구
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• 제47권
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• pp.157-182
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• 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
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• 제5권6호
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• pp.621-629
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• 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
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• 제5권2호
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• pp.145-150
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• 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
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• 제3권1호
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• pp.32-42
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• 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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.1037-1041
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• 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.

• 한국군사과학기술학회지
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• 제20권1호
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• pp.25-32
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• 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.

• 통상정보연구
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• 제14권4호
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• pp.339-360
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• 2012

본 논문은 글로벌금융위기시기 정부의 정책의지에 따라 운영될 수 밖 에 없었던 정책금융지원기관으로서, 공적수출신용보증기관 무보가 중소조선기업 보증지원 시 운영상의 문제점을 개선할 수 있도록 방안을 제시하다. 그러므로 본 연구는 기존연구와는 달리 중소조선사를 대표하는 S조선 지원 사례를 서지(書誌)분석을 통하여, 무보의 선박수출보증보험운영상의 불합리한 규정의 개선 뿐 만아니라 무보의 중소조선사 총괄 보증제도 까지 연구범위를 확대하여, 무보의 선박수출보증제도의 운영상의 문제점 및 시사점 뿐 만 아니라 경제위기상황에서 정부의 정책적 오류 발생 및 이와 연관된 정책집행기구의 역할에 대한 정책적 시사점을 제시하였다.

• 한국콘텐츠학회논문지
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• 제20권11호
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• pp.281-291
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• 2020

본 연구는 변액연금보험 보증준비금 산정을 위해 보험업감독업무시행세칙에 제시된 표준자산 등을 가우스-포와송 점프확산과정으로 추정해보고 점프위험에 대한 고려가 변액연금보험 최저연금적립금보증의 보증수수료율과 보증위험 측정에 미치는 영향을 살펴본다. KOSPI 200을 제외한 모든 자산의 수익률 분포가 두터운 꼬리(fat tail)를 가져 다수의 자산수익률에 점프가 존재하고 있음을 확인하였다. 변액연금보험의 최저연금적립금보증 현금흐름을 분석한 결과 국내주가지수와 해외주가지수(원화)는 점프위험을 고려할 경우 보증수수료율과 보증위험이 감소하며 이는 자산모형에 점프위험이 고려되면서 변동성이 감소하는 효과에 기인한 것이다. 반면 국내채권지수와 해외채권지수(원화)의 경우 점프위험 고려 시 래칫형 보증을 중심으로 보증수수료율과 보증위험의 수준이 다소 증가한다. 마지막으로 해외주가지수(달러화)와 해외채권지수(달러화)는 래칫형 보증을 중심으로 동종지수의 원화지수와 반대의 결과가 나타난다. 요컨대 수익률 점프를 고려하지 않을 경우 보증수수료율과 보증위험이 과소 또는 과대평가될 수 있음을 보여준다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1810-1815
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• 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.

• 한국안전학회지
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• 제29권6호
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• pp.1-8
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• 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.