• Journal of the Semiconductor & Display Technology
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• v.12 no.4
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• pp.39-44
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• 2013

In the semiconductor heat-treatment process, the temperature uniformity determines the film quality of a wafer. This film quality effects on the overall yield rate. The heat transfer of the wafer surface in the heat-treatment process equipment is occurred by convection and radiation complexly. Because of this, there is the nonlinearity between the wafer temperature and reactor. Therefore, the accurate prediction of temperature on the wafer surface is difficult without the direct measurement. The thermal camera and the T/C wafer are general ways to confirm the temperature uniformity on the heat-treatment process. As above ways have limit to measure the temperature in the precise domain under the micro-scale. In this study, we developed the thin film type temperature sensor using the MEMS technology to establish the system which can measure the temperature under the micro-scale. We combined the experiment and numerical analysis to verify and calibrate the system. Finally, we measured the temperature on the wafer surface on the semiconductor process using the developed system, and confirmed the temperature variation by comparison with the commercial T/C wafer.

• Journal of Advanced Navigation Technology
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• v.2 no.1
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• pp.43-52
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• 1998

In this paper, we have investigated the effects of geographic information on the performance of multiple ground target tracking system using multiple sensors. Geographic information is utilized in two cases: association and masking target measurement. Virtually no improvement is observed to the overall performance of tracking system when we applied mobility to the association procedure. Masking target measurement based on mobility produces desirable result that the number of false tracks is reduced. Since geographic information can be regarded as an additional sensor in sensor fusion paradigm, careful usage is required.

• Journal of the Korea Society for Simulation
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• v.3 no.2
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• pp.49-56
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• 1994

Performance measurement and analysis for computer systems has been studied for a long time. However, little attention has been focused on how to distribute a given budget to each part of a computer system for enhancing system performance maximally. In traditional approaches, performance enhancement is achieved by identifying a dominant system bottleneck and enhancing the bottleneck's performance. These approaches, however, often bring problems since the removal of a bottleneck may result in other bottlenecks. This paper proposes an approximated method for such budget distribution problem. For budget distribution, a critical set is defined. The set contains the servers of which performance changes affect the overall system performance significantly. Then, the given budget is distributed properly to every server in the critical set. To verify the proposed method, two benchmark experiments are carried out I SLAM environments. The experimental results show that the proposed method provides better results than the traditional method does in many cases.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.909-911
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• 1999

This paper proposes a robust control system with the disturbance observer for BLDC servo system. The overall control system is composed of the speed controller which is implemented with PI controller and the disturbance observer with free parameters. The BLDC servo system can improve the closed loop characteristics without affecting the command input response. The characteristics of the closed loop system is improved by suppressing disturbance effectively with the disturbance observer. Measurement noise is also considered by adjusting bandwidth of free parameters. We can overcome the drawbacks of the conventional PI controller. Finally, the performance of the controller is analyzed theoretically and some simulation results are presented to demonstrate the better performance than the conventional PI controllers.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.5
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• pp.474-482
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• 1992

This paper describes the speed control system of an induction type ac servomotor drive on the vector control basis of slip frequency and constant secondary flux control for a quick torque response. The system is composed of a digital controller using a SCB-V50 microprocessor and a PWM inverter with power MOSFETs for high speed switching. And, for the measurement of actual instantaneous currents, MDCS A070-051 hall sensors are employed. The rising time of step responce by this system through the test of a 600[W] ac servomotor is 30[ms]. Overall experimental result shows that the drive performance of the system is similar to that of a separately excited armature current control of a dc motior.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2489-2491
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• 2003

In this study, we implement the laser pattern controller using function generator IC. Overall system consists of : (1) laser excitation circuit and laser tube, (2) two small mirrors to reflect laser beam on the screen, (3) two small motors for X, Y axis enabling each attached mirrors to rotate, (4) controller for motor control and user interface, (5) system power. We explain the architecture of the system and required theory to implement the system. Finally, experimental results are illustrated to show the performance of the system.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.27-33
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• 2012

At present, the overall water resources monitoring ability in China is weak since there is an absence of a sound monitoring system and comprehensive monitoring information. In addition to the problem of weak management ability in monitoring, measurement and information, it can hardly meet the need of implementing the strictest management system of water resource and also restricts the practice of the system to some extent. The production states the necessity of further development of water resources monitoring ability and points out the concept of "One Country, One Account" for constructing water resources information. There is an analysis on the demand on further development of water resources monitoring ability and profound discussion about the strategies for supporting "three red-line" management.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.1 s.53
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• pp.88-96
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• 2009

This study proposes a wireless measurement system that is a new safety management system by using an FBG sensor and a PDA. The sensor part has many advantages of implementing a wireless measurement system, and the study emploies an FBG-LVDT sensor, FBG-STRAIN sensor, FBG-TEMP sensor, and FBG-ACC sensor, using FBG sensors. Also, the study show a configuration of a signal process system for operating a wireless transmission system of FBG sensors applied to the signal process system, and engrafted the cutting edge information technology industry in order to display from a remote distance using a PDA. In order to verify the applicability of the developed FBG sensors and wireless measurement monitoring system to the field, their accuracy, and usability, the study has conducted a static and dynamic test to a bridge in the field. The study made an assessment of service for the vibration of the bridge by applying dynamic data measured by an FBG-LVDT sensor and FBG-ACC sensor to Meister's curve and prepared methods for assessing the vibration of the bridge by proposing a standard of vibration limitation given the service of vibration of the bridge. As a follow up for this study, it would be necessary to set up an overall model for the standard of service assessment established in this study.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.58-59
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• 2014

EVM(Earned Value Management) is a management methodology for integrating scope, schedule and resources, and for objectively measuring project performance and progress. EVMS(Earned Value Management System) has been used for the performance measurement of R&D and construction projects in developed countries such as United States, United Kingdom and Australia. The nuclear power plant (NPP) projects in Korea have not applied EVMS. However, EVMS has come into request for overall schedule and cost risk management and performance measurement in overseas project of the nuclear power plant as a contractor. In this paper, based on the global EVMS guidelines, EVMS per unit processes have been developed for NPP projects. Moreover, using Business Process Management (BPM), it proposes an integrated process model with tasks, roles, and procedures for EVMS for NPP construction projects.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.1
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• pp.39-45
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• 2004

This paper proposes a new blind measurement model of blocking artifacts. This model plays an important role in the assessment and enhancement of image quality caused by block-based DCT coding system. The proposed model can measure blocking artifacts without reference to original images and consider the HVS based visual model such as frequency sensitivity and channel masking effect to detect and measure overall blocking artifacts quantitatively. The experimental results show that the proposed model is highly effective in measuring blocking artifacts.