• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.2
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• pp.323-336
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• 2000

In order to achieve the deployment of B-ISDN services in a short time, B-ISDN is being combined with terrestrial ATM network and satellite network which covers a widespread service range. This paper analyzes and investigates several previously existent CDV compensation methods in order to compensate CDV arising from interfacing satellite TDMA and ATM. Specifically to supplement the problems of timestamp and cell number counting methods, new Partial Timestamp mechanism for CDV compensation is proposed. The CDV compensating efficiency of the proposed mechanism is analyzed and evaluated by simulations. It goes to show that Partial timestamps mechanism has many advantages in the aspect of the CDV compensation.

• Journal of Mechanical Science and Technology
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• v.14 no.7
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• pp.764-772
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• 2000

In this paper, an engine-CVT integrated control algorithm is suggested by considering the inertia torque and the CVT ratio change response lag in acceleration. In order to compensate for drive torque time delay due to CVT response lag, two algorithms are presented: (1) an optimal engine torque compensation algorithm, and (2) an optimal engine speed compensation algorithm. Simulation results show that the optimal engine speed compensation algorithm gives better engine operation around the optimal operation point compared to the optimal torque compensation while showing nearly the same acceleration response. The performance of the proposed engine-CVT integrated control algorithms are compared with those of conventional CVT control, and It is found that optimal engine operation can be achieved by using integrated control during acceleration, and improved fuel economy can be expected while also satisfying the driver's demands.

• The Journal of the Acoustical Society of Korea
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• v.9 no.6
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• pp.53-61
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• 1990

Real-time implementations of the active adaptive noise controller are proposed and tested. There are three problems in active noise control such as real-time processing, an acoustic feedback of secondary signal and a time-delay of control system elements. For real-time processing, the DSP56001 was used. To avoid acoustic feedback, the secondary signal was excluded from prediction. And for compensation of time delay, the ahead prediction was applied. As the primary noise is reflected in space, the reflected noise should be controlled for perfect noise control. But in this case, the controller might be unstable. For solving the problem, it is proposed that the source noise and the reflected noise are predicted separately. Some experimental results show the stability and effectiveness of the proposed controller.

• The Transactions of the Korea Information Processing Society
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• v.7 no.9
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• pp.2980-2993
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• 2000

In order to achieve the rapid deployment of services. B-ISON network is being combined with terrestrial ATM and satellite network. Cell delay variation (CDV) generated by the difference of transfer mode between TOMA and ATM deteriorates transmission quality of the network system. We proposed the Partial Timestamps algorithm to supplement the problems of existing COV compensation methods. To minimize CDV and to utilize the satellite channels efficiently. only the optimized timestamps of a few cells within a control unit time of TDMA are selected and transmitted to the receiving earth station. The COV compensating efficiency of Partial Timestamps is evaluated by simulation. It is confirmed that CDV compensation capability of the proposed mechanism is superior to the other methods.

• Smart Structures and Systems
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• v.14 no.6
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• pp.1173-1196
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• 2014

Real-time dynamic substructuring tests have been conducted on a cable-deck system. The cable is representative of a full scale cable for a cable-stayed bridge and it interacts with a deck, numerically modelled as a single-degree-of-freedom system. The purpose of exciting the inclined cable at the bottom is to identify its nonlinear dynamics and to mark the stability boundary of the semi-trivial solution. The latter physically corresponds to the point at which the cable starts to have an out-of-plane response when both input and previous response were in-plane. The numerical and the physical parts of the system interact through a transfer system, which is an actuator, and the input signal generated by the numerical model is assumed to interact instantaneously with the system. However, only an ideal system manifests a perfect correspondence between the desired signal and the applied signal. In fact, the transfer system introduces into the desired input signal a delay, which considerably affects the feedback force that, in turn, is processed to generate a new input. The effectiveness of the control algorithm is measured by using the synchronization technique, while the online adaptive forward prediction algorithm is used to compensate for the delay error, which is present in the performed tests. The response of the cable interacting with the deck has been experimentally observed, both in the presence of delay and when delay is compensated for, and it has been compared with the analytical model. The effects of the interface delay in real-time dynamic substructuring tests conducted on the cable-deck system are extensively discussed.

• ETRI Journal
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• v.28 no.5
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• pp.680-683
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• 2006

One objective in developing the next generation of wireless communication systems is to increase data rates and reliability. A promising way to achieve this is to combine multiple-input and multiple-output signal processing with a space-time coding scheme, which offers higher coding and diversity gains and improves the spectrum efficiency and reliability of a wireless communication system. It is noted, however, that time delay differences and phase differences among different channels increase symbol interference and degrade system performance. In this letter, we investigate phase differences and their effects on multiple-input and multiple-output systems, and propose a compensation algorithm for the Rayleigh fading model to minimize their effects.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.56-59
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• 1997

Vision system is mainly consist of three parts of perception, action. One of these parts, perception system detects visual target in surrounding environment. Block-based motion estimation with compensation is one of the popular approaches without accuracy. The hierarchical method the optical flow with gradient is used to improve optical flow time delay.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.05a
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• pp.102-103
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• 2010

• IEMEK Journal of Embedded Systems and Applications
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• v.15 no.1
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• pp.17-23
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• 2020

We propose a system time synchronization method between embedded Linux-based distributed control devices by using Transmission Control Protocol (TCP) communication and General Purpose Input Output (GPIO) device. The GPIO signal is used as the trigger signal for synchronization and the TCP communication is used to transfer the system time of master Linux, which serves as the reference clock, to slave Linux. Precise synchronization performance is achieved by measuring and compensating for the propagation delay of GPIO signal and the acquisition and setting latency of Linux system time. We build an experimental setup consisting of two embedded Linux systems, and perform extensive experiments to verify the performance of the proposed synchronization method.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2723-2725
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• 2005

In this paper, a robust $H{\infty}$ stabilization problem to a uncertain discrete-time nonlinear systems with time-delay via fuzzy static output feedback is investigated. The Takagi-Sugeno (T-S) fuzzy model is employed to represent an uncertain nonlinear systems with time-delayed state. Then parallel distributed compensation technique is used for designing of the robust fuzzy controller. Using a single Lyapunov function, the globally asymptotic stability and disturbance attenuation of the closed-loop fuzzy control system are discussed. Sufficient conditions for the existence of robust $H{\infty}$ controllers are given in terms of linear matrix inequalities via similarity transform and congruence transform technique.