• Journal of Institute of Control, Robotics and Systems
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• v.5 no.7
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• pp.836-840
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• 1999

Linear motion and angular motion in task space are handled separately in joint velocity planning for redundant robot manipulators. In solving inverse kinematic equations with given joint velocity limits, we consider the order of priority for linear motion and angular motion. The proposed method will be useful in such applications where only linear motions are important than angular motions or vice versa.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.346-351
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• 1987

In this study, digital simulation with nonlinear modeling is carried out to analyse the performance of a hydraulic servomotor system developed for the position control of a large inertia. Nonlinear element, such as nonlinear pressure flow relationships of servovalve, valve spool limits, nonlinear friction, and backlash and resilience of gear system are included in the simulation along with the dynamic characteristics of variable delivery pump compensation mechanism. Simulation results are compared with experimental results for both step and sinusoidal inputs. Independent of input magnitude, both results are in good agreement with minor differences in detail.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.47-50
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• 2007

The maximum current level in organic light emitting diodes (OLED) panel influences the maximum pixel luminance, the width of $V_{DD}$ lines, the maximum power consumption and the lifetime. We propose an algorithm that limits the overall current without any palpable image artifacts, and therefore, improve panel parameters by program.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.616-619
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• 2004

As interests Un virtual reality being increased, the importance of HCI(Human computer interaction) field using gesture is also increased. However, in the preceding gesture recognition, the requirement of high-cost peripheral equipments limits users right. In this paper we suggest that through using low cost of USB PC-camera users are allowed to have more flexibly and cost down so that it can be adopted much commonly.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1993.10a
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• pp.157-161
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• 1993

Optical devices and electronic equipments used in the laboratory of the synchrotron light source building of the accelerator have stringent vibration limits. In order to control the vibration of the building structure and HVAC systems which are main vibration sources are evaluated using experimental modal analysis. Double anti-vibration system is used for the HVAC system and results show that the double anti-vibration system reduces the vibrations of the building to acceptable levels.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.1
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• pp.106-110
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• 2008

The requirement for customized learning environments is increasing with the development of Web 2.0 technology To personalize services in E-learning, there are various functions available to the user. However, some components have fixed or inflexible functionality that limits what can be changed, and customization information has not been used for other purposes. In this paper, we propose an e-Space manager for the dynamic customization of learning environment control units. The proposed method can confirm which areas users have customized and how they have customized them. The advantage is that users can control their own learning environments, including not only the format, but also the content within the limits of the underlying system. The customization information is captured to confirm the competency model.

• Nuclear Engineering and Technology
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• v.47 no.7
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• pp.838-848
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• 2015

One of the most important operations in nuclear power plants is load following, in which an imbalance of axial power distribution induces xenon oscillations. These oscillations must be maintained within acceptable limits otherwise the nuclear power plant could become unstable. Therefore, bounded xenon oscillation is considered to be a constraint for the load following operation. In this paper, the design of a sliding mode control (SMC), which is a robust nonlinear controller, is presented.SMCis ameansto control pressurized water nuclear reactor (PWR) power for the load following operation problem in a way that ensures xenon oscillations are kept bounded within acceptable limits. The proposed controller uses constant axial offset (AO) strategy to ensure xenon oscillations remain bounded. The constant AO is a robust state constraint for the load following problem. The reactor core is simulated based on the two-point nuclear reactor model with a three delayed neutron groups. The stability analysis is given by means of the Lyapunov approach, thus the control system is guaranteed to be stable within a large range. The employed method is easy to implement in practical applications and moreover, the SMC exhibits the desired dynamic properties during the entire output-tracking process independent of perturbations. Simulation results are presented to demonstrate the effectiveness of the proposed controller in terms of performance, robustness, and stability. Results show that the proposed controller for the load following operation is so effective that the xenon oscillations are kept bounded in the given region.

• Journal of Korean Society for Quality Management
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• v.32 no.2
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• pp.132-153
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• 2004

CUSUM control charts are widely used to monitor processes with small shifts. CUSUM control charts are, however, less effective in detecting for recurring cycles or frequent small shifts in the processes. With Shewhart control charts, we have applied the variety of run rules to check the stability of process in addition to the situations that some points fall outside the control limits. In this paper, we propose the Z -CUSUM control chart for monitoring the process with recurring cycles or frequent small shifts by use of the zone concept as like the Shewhart control charts.

• Industrial Engineering and Management Systems
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• v.16 no.1
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• pp.109-117
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• 2017

In this article, a control chart based on multiple dependent (or deferred) state sampling for the gamma distributed quality characteristic is proposed using the gamma to normal transformation. The proposed control chart has two pairs of control limits, which can be determined by considering the in-control average run length (ARL). The shift in the scale parameter of a gamma distribution is considered and the out-of-control ARL is evaluated. The performance of the proposed chart has been shown for different levels of the parameters of the proposed control chart. It is also shown that the proposed chart is better than the Shewhart chart in terms of ARLs. A case study with a real data has been included for the practical usage of the proposed scheme.

• Proceedings of the Korean Society for Quality Management Conference
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• 2004.04a
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• pp.57-63
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• 2004

CUSUM control charts are widely used to monitor processes with small shifts. CUSUM control charts, however, are less effective in detecting for recurring cycles or frequent small shifts in the process. With Shewhart control charts, we have applied the variety of run rules to check the stability of process in addition to the situations that some points fall outside the control limits. In this paper, we propose the Z-CUSUM control chart for monitoring the process with recurring cycles or frequent small shifts by use of the zone concept as like the Shewhart control charts.