• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2164-2166
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• 2002

This paper present a controller design scheme for time-delay system. The Smith Predictor has been proposed to solve the problem of time-delay. But this structure has a condition that parameters of plant and model have to be matched accurately. Because of this condition, it is not applied broadly in practical industrial process field. In this paper, the 2nd-order model with dead-time is used as plant model of the Smith Predictor and a main controller is designed by using the effect of mismatch between plant and model.

• Tunnel and Underground Space
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• v.16 no.4 s.63
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• pp.326-333
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• 2006

In this study, the vibration waveform of the single hole which is not interfered from the different blasting holes is separated, the each dominant frequency which is determinated through the Fast Fourier Transform(FFT) is measured. Also the separation waveform executed a superposition modeling which changes to delay time from 1ms to 80 ms in 1ms interval and controls the number of blasting holes from 2 holes to 15 holes in order to investigate the effect of PPV according to the duration time of the vibration and the number of blasting holes. As a result of analysis, the longer the duration time of the vibration, the longer the delay time which is not interfered from the different blasting holes and the effect regarding the number of blasting holes from inside identical delay time did not appear a lot.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1930-1933
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• 1991

In this paper, the robustness of self turning controller on the continuous time-delay system is investigated. The polynomial identification method using continuous time exponentially weighted least square algorithm is used for estimating the time.-delay system parameters. The pole-zero and pole placement method are adopted for the control algorithm. On considering the control weighting factor and reliability filter the effect of unmodeled dynamics of the plant are examined by the simulation.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.2
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• pp.156-160
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• 2012

In this paper, we investigate the effect of asynchronous haptic and video feedback on the performance of teleoperation. To analyze the effect, a tele-manipulation experiment is specially designed, which operator moves square objects from one place to another place by using master/slave telerobotic system. Task completion time and total number of falling of the object are used for evaluating the performance. Subjective study was conducted with 10 subjects in 16 different combinations of video and haptic feedback while participants didn't have any prior information about the amount of each delay. Initially we assume that synchronized haptic and video feedback would give best performance. However as a result, we found that the accuracy was increased when haptic and video feedback was synchronized, and the completion time was decreased when one of the feedback (either haptic or video) was decreased. Another interesting fact that we found in this experiment is that it showed even better accuracy when haptic information arrives little bit earlier than video information, than the case when those are synchronized.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.1
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• pp.89-93
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• 2009

In this paper, we investigated effect of sensing time on the performance of enhanced spectrum sensing method, which is the energy detector with multiples of verification using time delay, under Suzuki channel. We assumed that SNR is 1dB, $P_{FA}=0.1$ and various mobile speed such as 3, 60, 110 km/h. The performance is investigated by simulation and compared to that of conventional energy detector.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.35-42
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• 2003

In this paper, we classified the wavelength reservation mechanisms of optical burst switching (OBS), and investigated the path length priority effect of the offset time/delayed reservation (OT/DR)-based scheme like the just-enough-time (JET) protocol. And, we showed that the fiber delay line (FDL)-based scheme can avoid the path length priority effect in multiple hop network environments. Also, we proposed a novel FDL/DR with hop-by-hop priority increasing (HPI) scheme which can improve the end-to-end throughput by increasing the priority of bursts hop-by-hop using the input FDLs at each node. The simulation results showed that the proposed FDL/DR with HPI scheme could avoid the path length priority effect and enhance the end-to-end throughput in multiple hop network environments.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.6
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• pp.81-91
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• 2008

In this study, data collection delay time generated in bus information system is analysed and improvement on system reliability by minimizing the delay time is suggested. To minimize the data collection delay time (call setup time), factors on data collection phase are analyzed. Each connecting time that it occurs from wireless communication during data collection phase, is selected as a main effective variable and a model for selecting an optimum communication point to minimize the effect of data delay time by each connecting time is suggested. In this model, minimization of the point between the time carrying out wireless communication and vehicle moving time, is calculated and the difference between the bus arrival time and information delivered time to the passenger is reduced. The test results for the proposed model in BIS using a CDMA (Code Division Multiple Access) communication show that delay time in real system operation has been improved. The minimum data collection delay time based on optimal communication position leads to the better reliability for Bus Information System. This study can be applied to the selection of optimal communication position and detection position instead of empirical methods.

• International conference on construction engineering and project management
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• 2024.07a
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• pp.137-144
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• 2024

Public infrastructure projects are implemented to achieve targeted economic development of nations. However, due to the delayed execution of projects, the investment cost of the project increases in proportion to time overrun. The increased investment cost for the defined scope of project may have an effect on the achievement of planned future benefits, but the effect of delay on the loss of estimated benefits is not well explored. The primary objective of this research is to assess the effect of delayed execution of road and bridge construction projects on the estimated future benefits. Furthermore, the relationship between delay and the percentage loss of future benefits is modeled using the linear regression analysis. The data consists of 395 road and 248 bridge construction contracts under the Department of Roads, Nepal. The statistical analysis of road and bridge construction contracts showed that there is a reduction in estimated benefits in future years due to the effect of delay. The relationship between the percentage loss of estimated benefit and delay period in months was found to be significant for both road and bridge contracts. The results show that delay not only affects the short-term cost overrun but also the achievement of estimated future benefits. This research thus contributes valuable insights into the understanding of the impact of project delays on both cost overruns and the loss of estimated future benefits. Furthermore, this research has practical implications for policymakers, private sector investors, and financing agencies involved in infrastructure development projects.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.907-910
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• 2001

In this paper, we address a new time delay estimation method using third-order statistics and subband adaptive filtering to improve the accuracy of target detection for acoustic backscattered signals in a noise interference environment. Each reference and primary signals are decorrelated using the multiresolution analysis framework through a M-band discrete wavelet transform(M-DWT). Then noise effect can be reduced. Here, time delays are estimated iteratively in each subband using two different adaptation mechanisms that minimize the mean squared error (MSE) between the references and primary signal. More specifically, third-order cumulants and projection cross-correlation(PCC) criterion are utilized to achieve an effective SNR improvement for the time delay estimation.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.123-125
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• 2004

In order to achieve high efficiency and low cost, new high-speed addressing method is suggested. This can be achieved by reducing the address discharge delay time through the priming effect. This paper suggests a new ADR (Address During Reset) driving method which provides priming particles by using a separated driving method without adding auxiliary electrode or auxiliary discharge. The experimental results show an approximately loons reduction in the formative delay time of address discharge and a reduction in jitter of over 200ns. Also, due to enough time being available for reset, there was a reduction in light emitted during reset of about 29% which improved the dark contrast ratio considerably.