• 한국안전학회지
• /
• 제16권2호
• /
• pp.51-56
• /
• 2001

This paper is proposed an efficiency optimization control algorithm for a synchronous reluctance motor (SynRM) which minimizes the copper and iron losses. fen exists a variety of combinations of d and q-axis current which provide a specific motor torque. The objective of the efficiency optimization controller is to seek a combination of d and q-axis current components, which provides minimum losses at a certain operating point in steady state. It is shown that the current components which directly govern the torque production have been very well regulated by the efficiency optimization control scheme. The proposed algorithm allows the electromagnetic losses in variable speed and torque drives to be reduced while keeping good torque control dynamics. Simulation results are presented to show the validity of the proposed algorithm.

• 제어로봇시스템학회논문지
• /
• 제15권10호
• /
• pp.988-993
• /
• 2009

In this paper, we deal with a tracking gain-up controller design problem to control effectively the shake of tracking actuator after a track seek. A minimum tracking gain-up open-loop gain can be calculated by estimating the shake of tracking actuator and a desired transient specification is considered to diminish effectively the shake of actuator. A tracking gain-up controller is designed by considering a robust $H_{\infty}$ control problem with a regional stability constraint. The proposed tracking gain-up controller design method is applied to the track-following system of a DVD recording device and is evaluated through the experimental results.

• Coupled systems mechanics
• /
• 제13권1호
• /
• pp.73-93
• /
• 2024

In this work, we propose combining an advanced optimal control algorithm with a geometrically exact beam model. For simplicity, the 2D Reissner beam model is chosen to represent large displacements and rotations. The difficulty pertains to the nonlinear nature of beam kinematics affecting the tangent stiffness matrix, making it non-constant, which compromises direct use of optimal control methods for linear problems. Thus, we seek to accommodate a time varying control using linear-quadratic regulator (LQR) algorithm with the proposed geometrically nonlinear beam model. We provide a detailed theoretical formulation and its numerical implementation in a variational format form. Several illustrative numerical examples are provided to confirm an excellent performance of the proposed methodology.

• 디지털산업정보학회논문지
• /
• 제9권3호
• /
• pp.195-209
• /
• 2013

Purpose of this study is to empirically consider relation between QM activity factor and management result. For this, following 6 major variables of QM activity were established as independent variable; CEO's leadership, communication, process control, standardization, full participation and education/training while satisfaction of members and improvement of quality were established as dependent variable. And, a model was set up and hypothesis verification was conducted on the basis of data collected through questionnaires. The results are summarized as follows; First, QM factors which influenced satisfaction of members in management result were CEO's leadership, communication, process control, full participation and education/training but 'standardization' factor was not statistically significant. Second, QM factors which influenced improvement of quality in management result were CEO's leadership, communication, standardization, full participation and education/training but 'process control' factor was not statistically significant. Third, among main factors of QM activity, the factor which preferentially influenced satisfaction of members was 'full participation' factor while the factor which preferentially influenced improvement of quality was 'standardization' factor. According to such results, it is required to seek a statistical method regarding QM activity with focus on the factor of 'full participation' and 'standardization' among other things for the purpose of satisfaction of members as well as improvement of quality. It is believed that implication of this study can be useful information to realize management result considering main factors of QM activity and that it also can be basic reference data to seek a statistical method for satisfaction of members and improvement of quality by grasping core factors having influence over QM activity.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권2호
• /
• pp.1159-1163
• /
• 2013

International meetings on various aspects of cancer- its etiology, its diagnosis, its treatment, its palliation, and its prevention and control are held frequently. Many have similar themes, and many seek and receive the same speakers and audiences. A fundamental question arises: what difference does any individual meeting/congress/conference make or add to our understanding of the relevant issues? While many meetings conduct evaluations at the end of the Congress, few use evaluation as a tool to guide design, implementation, and evaluation of both short and long term impacts, and address the question of "what difference did the Congress make". The International Cancer Control Congresses, which are held biennially in different regions of the world, took the opportunity to use evaluation in this way, and ask the relevant questions. This paper describes that evaluation session of the ICCC4, held in Seoul, Korea in November 2011, which was part of the larger evaluation issue.

• 한국항해학회지
• /
• 제23권3호
• /
• pp.35-44
• /
• 1999

This research aims to seek active control of ball-beam position stability by resorting to neural networks whose layers are given bias weights. The controller consists of an LQR (linear quadratic regulator) controller and a neural networks controller in parallel. The latter is used to improve the responses of the established LQR control system, especially when controlling the system with nonlinear factors or modelling errors. For the learning of this control system, the feedback-error learning algorithm is utilized here. While the neural networks controller learns repetitive trajectories on line, feedback errors are back-propagated through neural networks. Convergence is made when the neural networks controller reversely learns and controls the plant. The goals of teaming are to expand the working range of the adaptive control system and to bridge errors owing to nonlinearity by adjusting parameters against the external disturbances and change of the nonlinear plant. The motion equation of the ball-beam system is derived from Newton's law. As the system is strongly nonlinear, lots of researchers have depended on classical systems to control it. Its applications of position control are seen in planes, ships, automobiles and so on. However, the research based on artificial control is quite recent. The current paper compares and analyzes simulation results by way of the LQR controller and the neural network controller in order to prove the efficiency of the neural networks control algorithm against any nonlinear system.

• 한국국방경영분석학회지
• /
• 제3권2호
• /
• pp.79-89
• /
• 1977

The purpose of this thesis is to overcome the shortcomings of the existing system which lacks cost-conciousness and does not consider the essentiality or the importance of an item, and to seek the method of providing effective, efficient and economic supply which is the objective of the military inventory management. Selective management technique and lot size model whose demand, and order and shipping time are distributed, are intorduced, and required distributions and parameters are analyzed. Finally hypothetical data are utilized to obtain the model output, which are compared with the existing model and analyzed.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.100.1-100
• /
• 2001

With the prolific growth of cable, satellite digital broadcasting and internet related industry, new digital contents are being demanded. Today, more end-users seek participations in the media through interactivity. Visual tracking technology, based on image processing, is mainly used in fields of human face tracking, security inspection, and traffic monitoring applications. In this research, we describe the interactive modules such as information display, e1-commerce and other services along with on-screen visuals on the streaming media using object visual tracking technology. The ...

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 하계학술대회 논문집 F
• /
• pp.2217-2220
• /
• 1997

To achieve the high performance speed control of synchronous permanent magnet motor, the influence of iron loss can not be negleced as the increase of driving frequency with high speed operation. This paper proposes a maximum efficiency control algorithm for permanent magnet synchonous motors by controlling the d-axis component of the armature current at any speed and torque. The objective of the optimum efficiency controller is to seek a combination of d-q axis current components which provide minimum input power (minimum losses) at a certain operating point by adding a small amout of perturbation to the d-axis current reference.

• Journal of applied mathematics & informatics
• /
• 제15권1_2호
• /
• pp.127-146
• /
• 2004

In this paper we consider a heat flow in an inhomogeneous. body without internal source. There exists special initial and boundary conditions in this system and we intend to find a convenient coefficient of heat conduction for this body so that body cool off as much as possible after definite time. We consider this problem in a general form as an optimal control problem which coefficient of heat conduction is optimal function. Then we replace this problem by another in which we seek to minimize a linear form over a subset of the product of two measures space defined by linear equalities. Then we construct an approximately optimal control.