• Journal of Institute of Control, Robotics and Systems
• /
• v.7 no.4
• /
• pp.281-287
• /
• 2001

In this paper, we deal with a decentralized control scheme with input compensation form for gantry crane systems. By considering the gantry cranes characteristics, the system is decentralized into two subsystems, the travelling and swaying subsystem and the hoisting subsystem. For decentralizing the system, a simple algorithm is proposed using the observability canonical form. The decentralized subsystems include unknown inputs that one coupled with other subsystems and actuator failures. These unknown input and actuator failures are estimated by using PI observation techniques. And those estimated values are used to construct an input compensation form. Finally, the proposed decentralized control scheme for the gantry crane systems is verified by crane simulation.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.17 no.1
• /
• pp.11-19
• /
• 1992

This paper proposes a reduced order method which reduces passband error by changing controllability and observability gramian based on weighted functions in the linear time invariant system. In the case that the 4-order model is the reduced to 3-order model in the low-pass filter, the QEI in the proposed method is improved to 6.15724 compared to 10.16464 in the balanced realization method and the sensitivity is improved to 5.45962 compared to 7.790568. The frequency property curves show that the proposed method is superior to the balanced realization method.

• Proceedings of the KIEE Conference
• /
• 1987.11a
• /
• pp.133-136
• /
• 1987

This paper presents a new algorithm of optimal measurement system by using band matrix characteristic respectively for state estimation. A performance index of measurement system is established to reflect relation among measurement sets, probability of measurement failure and cost of individual meter installation. Selection ranking in the candidates of measurement sets is composed to guarantee the observability for any any single meter outage. Performance index sensitivity is introduced and recursive formula which based on the matrix inversion lemma used for selection. The proposed algorithm is composed of successive addition algorithm, successive elimination algorithm and combinatorial algorithm. The band matrix characteristic could save in memory requirements and calculate the performance index faster than earlier.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2004.10a
• /
• pp.539-553
• /
• 2004

This paper models and solves contracting schemes for both when quality is perfectly observable and when quality is not perfectly observable in supply chain. When quality is perfectly observable, the first-best optimal solution which is that the marginal utility of procurer obtained from the quantity and quality supplied by suppliers (the price) is equal to the marginal cost to produce the quantity and quality is obtained. However, when quality is not perfectly observable to procurers the optimal solution cannot be the first-best but the second-best where the price is greater than the marginal cost to produce the quantity and quality and social welfare is less than that of the first-best solution.

• ETRI Journal
• /
• v.28 no.2
• /
• pp.131-144
• /
• 2006

This work demonstrates a dead-reckoning (DR) scheme for a low-cost land navigation system and a DR/GPS system design using the sigma point Kalman filter (SPKF). T hrough an observability analysis and some simulations, it is shown that the performances of a stand-alone DR system and DR/GPS system can be improved by employing the proposed DR scheme and SPKF. By using the designed DR scheme and filter, the stand-alone DR system does not have any undetectable errors occurring on the curve trajectory. And the DR/GPS system can provide a stable and seamless navigational solution even in the case where the initial heading estimation error is large, such as 160 degrees, or when the GPS signal is unavailable due to tunnels, buildings, and so on. Simulation results indicate a satisfactory performance of the proposed system.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.4
• /
• pp.304-312
• /
• 2011

In an oligopolistic market, only a few firms account for most or all of total production, e.g., automobile, steel, and computer industries. For a dynamic oligopolistic market with two firms competing in quantities, we show that supervisory control theory of discrete event systems provides a novel approach to solve the dynamic oligopoly problem with the aim of maximizing the profits of both firms. Specifically, we show that the controllability, observability, and nonblocking property (which are the core concepts in supervisory control theory) are the necessary and sufficient conditions for two oligopolistic firms in disequilibrium to eventually reach equilibrium states of maximizing the profits of both firms.

• Journal of the Korean Home Economics Association
• /
• v.42 no.9
• /
• pp.177-193
• /
• 2004

The purpose of this study was to explore consumer behavior of perfume products. Data were collected through 7 focus group interviews with 33 female consumers whose ages ranged between the 20's and 40's. According to analysis of groups divided by age and frequency of use, some group differences were found in information source, purchase place, consideration factors, fragrance preference, etc. The study results indicated that perfume consumption behaviors could be explained in part by the innovation adoption and communication theories. Especially, relative advantage, compatibility, observability, and trialability were important factors influencing consumers' adoption of new perfume. Also, many respondents used perfume as a tool to present their own image and identity, as well as to send messages regarding their mood and condition to others.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.8 no.1 s.20
• /
• pp.25-31
• /
• 2005

PLA(Passive Linear Array) system has been primarily utilized to detect and track underwater targets, such as submarines. This system has difficulty in distinguishing between underwater targets and surface ships in a dense target environment. And a single-PLA system does not provide target state observability. At least two PLAs are necessary to observe a track uniquely. To classify and localize the underwater targets effectively, first of all, it is very of importance to discriminate the surface ships in the multi-target environment. These problems can be overcome by the association of distributed PLAs and radars. In this paper, we present an algorithm to solve the track-to-track association of the heterogeneous data from three PLAs and one radar are noncollocated with known sensor positions. Also, this paper shows the simulation results to verify the proposed algorithm.

• Proceedings of the KIEE Conference
• /
• 2007.10a
• /
• pp.219-220
• /
• 2007

Image plane상에서의 목표의 크기, 시선각 (Line-of-Sight angle) 및 관측자의 상태 정보 등을 이용하여 목표의 상태를 추정한다. 표적 모델을 Linear Time Varying(LTV) system처럼 다룰 수 있음을 밝히고, 이를 이용하여 가관측성(observability)이 성립하는 조건을 구하고 Kalman filter를 이용하여 비선형 추정기를 설계한다. 그리고 등가속도 표적 추정, 미사일의 정지 표적 공격 등의 모의실험에 적용해 본다.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.49 no.3
• /
• pp.136-141
• /
• 2000

This paper presents the design of an H$\infty$ based robust Static Synchronous Compensator (STATCOM) supplementary controller to suppress the subsynchronous resonance (SSR) in the series-compensated system. The IEEE second benchmark, System-l model is employed for this study. In order to design the effective controller, the modal controllability and observability indices to the oscillation modes are considered. Comprehensive time domain simulations using a nonlinear system model that the proposed STATCOM supplementary controller can suppress the SSR efficiently in spite of the variations of power system operating conditions.