• Journal of Educational Research in Mathematics
• /
• v.11 no.1
• /
• pp.113-121
• /
• 2001

The purpose of this paper is to investigate the significance and the role of intuitive model and the example of its development. Intuitive model is the tools of intuition in mathematics and the sources for the creative learning mathematics. It consists of the analogical model, paradigmatic model and diagrammatic model. Intuitive model must have a number features in order to be really useful as heuristic devices. It must present a high degree of natural, consistent and structural correspondence with the original. It must also correspond to human information processing characteristics and enjoy a relative autonomy with respect to the original. Sometimes, the difficulty in teaming mathematics stems from the abstractive characteristics of mathematics. So, we have to assist students' learning using the intuitive model that reveals the concrete representation and various changes of mathematical concepts, rules and principles.

• Korean Journal of Acupuncture
• /
• v.28 no.3
• /
• pp.187-199
• /
• 2011

Objectives : Pyoyubu (標幽賦), one of the classics in the science of acupuncture and moxibustion was written by Tu hankyoung (竇漢卿) during the Kum-Won dynasty of China (A.D 1196-1280). This paper is to explore his academic thoughts and make its correct interpretation with new copious notes. Methods : The translation was based on Original Chimgudaesung (原本鍼灸大成) and revisals of Chimguchuiyoung (鍼灸聚英), Yukyoungbuik (類經附翼), New Chimgudaesung (新鍼灸大成), etc. The format of this paper is in poetry and prose in order to abide by the original text. Results and Conclusions : The final part is devoted to five critical thinking on the text, which provides the fundamental principles and clinical guidelines for the current theory of acupuncture.

• Korean Management Science Review
• /
• v.15 no.2
• /
• pp.125-142
• /
• 1998

The aggregation on linear large-scale dynamic systems is examined in this paper and a "two-step" approach is proposed. In this procedure, the aggregated system consists of two subsystems. The first subsystem represents aggregation through the retainment of dominant eigenvalues of the original system, leading to a first approximation of the desired output of the original system. The purpose of augmenting it with a second subsystem is to provide an estimation of the error on the first approximation, thus permitting a second correction to the output approximation and resulting in an output approximation of greater accuracy. Optimization techniques are discussed for the determination of unknown parameters in the aggregated system. These techniques use minimization principles of certain suitable performance indices and are developed for both single input-single output and multiple input-multiple output system. Numerical examples illustrating these procedures are given and the results are compared with those obtained using existing methods. Finally, a pharmacokinetics problem is studied from the aggregation point of view.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.19 no.2
• /
• pp.229-244
• /
• 1994

In many applications of simulation-optimization, when comparing two or more alternatives, it is crucial to be able to estimate the confidence intervals on the outputs of interest with a reasonable level of accuracy. This acuracy has often been tested by the closeness of the coverage of the estimated confidence interval to the intended coverage. In this paper two variations to the Batch-Means Method of estimating the confidence intervals are presented and their performance are compared with the original method. The results indicate that the Batch Means Method modified by factors obtained by a second order autoregressive method is superior to the original and the one modified based on factors obtained from autocorrelation analysis.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1735_1736
• /
• 2009

This paper discusses about a robust servo system applying PID control to PMSM. The system has robustness by Sliding Mode Controller. A novel sliding surface is defined by virtual state. This sliding surface has nominal dynamics of an original PID control system. So Sliding Mode Control(SMC) technique can be used with PID controller. Its design is based on the augmented system whose dynamics have a higher order than that of the original system. The reaching phase is removed by using an initial virtual state whitch makes the initial sliding function equal to zero.

• Journal of KSNVE
• /
• v.6 no.5
• /
• pp.567-574
• /
• 1996

This paper concerns an articulated space robot with flexible links. The equations of its motion are derived by means of the Lagrangian mechanics. Assuming that magnitude of elastic motions are relatively small, the perturbation approach is taken to separate the original equations of motion into linear and nonlinear equations. Th effect the desired payload motion, open loop control inputs are first determined based on the nonlinear equations. One the other hand, in order to reduce the positional errors during the maneuver, vibration suppression is actively done with a feedforward control for disturbance cancellation to some extent. Additionally, for performance robustness against residual disturbance, an LQ control modified to have a prescribed degree of stability is applied based on the linear equations. Measurement equations are formulated to be used for the maximum likelihood estimator to reconstruct states from the original robot equations of motion. Finally, numerical simulations show effectiveness of the proposed control design scheme.

• Journal of Korean Institute of Industrial Engineers
• /
• v.9 no.2
• /
• pp.3-8
• /
• 1983

The multiple choice knapsack problem is modified. To solve this modified multiple choice knapsack problem, Lagrangian relaxation is used, and to take advantage of the special structure of subproblems obtained by decomposing this relaxed Lagrangian problem, a modified ranking algorithm is used. The K best rank order solutions obtained from each subproblem as a result of applying modified ranking algorithm are used to formulate restricted problems of the original problem. The optimality for the original problem of solutions obtained from the restricted problems is judged from the upper bound and lower bounds calculated iteratively from the relaxed problem and restricted problems, respectively.

• Structural Engineering and Mechanics
• /
• v.63 no.4
• /
• pp.439-446
• /
• 2017

This work proposes an original single variable shear deformation theory to study the buckling analysis of thick isotropic plates subjected to uniaxial and biaxial in-plane loads. This theory is built upon the classical plate theory (CPT) including the exponential function in terms of thickness coordinate to represent shear deformation effect and it involves only one governing differential equation. Efficacy of the present theory is confirmed through illustrative numerical examples. The obtained results are compared with those of other higher-order shear deformation plate theory results.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.427-431
• /
• 1996

The MRAS proposed by Schauder [8] is modified to improve robustness to the change of load torque and/or the variation of the stator resistance. The difference between the voltage and the current model is fed into the current model via proportional and integral gains. In order to generalize the MRAS, supposing that the rotor speed is time varying, we add a compensating term to the current model. It does not alter the Popov's integral inequality condition. Also, the asymptotic stability of the modified MRAS (MMRAS) is shown with the stability proof technique as in the original paper. By the simulation works, it is verified that the MMRAS obtains improved performance than the original MRAS.

• Journal of Institute of Control, Robotics and Systems
• /
• v.5 no.5
• /
• pp.505-510
• /
• 1999

In this paper, a novel sliding surface is proposed by defining a novel virtual state. This sliding surface has nominal dynamics of an original system and makes it possible that the sliding mode control(SMC) technique is used with the various types of controllers. Its design is based on the augmented system whose dynamics have a higher order than that of the original system. The reaching phase is removed by using an initial virtual state which makes the initial sliding function equal to zero.