• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.2
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• pp.495-502
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• 2013

In the mobile Ad hoc Network(MANET), improving technique for management and control of topology is recognized as an important part of the next generation network. In this paper, we proposed an efficient node life time management of ATICC(Adaptive Time Interval Clustering Control) in Ad-hoc Networks. Ad-hoc Network is a self-configuration network or wireless multi-hop network based on inference topology. This is a method of path routing management node for increasing the network life time through the periodical route alternation. The proposed ATICC algorithm is time interval control technique depended on the use of the battery energy while node management considering the attribute of node and network routing. This can reduce the network traffic of nodes consume energy cost effectively. As a result, it could be improving the network life time by using timing control method in ad-hoc networks.

• Journal of Advanced Navigation Technology
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• v.23 no.6
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• pp.577-583
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• 2019

A dynamic system is called positive if any trajectory of the system starting from non-negative initial states remains forever non-negative for non-negative controls. In this paper, we consider the new stability condition for the positive time-varying linear discrete interval systems with time-varying delay and unstructured uncertainty. The delay time is considered as time-varying within certain interval having minimum and maximum values and the system is subjected to nonlinear unstructured uncertainty which only gives information on uncertainty magnitude. The proposed stability condition is an improvement of the previous results which can be applied only to time-invariant systems or had no consideration of uncertainty, and they can be expressed in the form of a very simple inequality. The stability conditions are derived using the Lyapunov stability theory and have many advantages over previous results using the upper solution bound of the Lyapunov equation. Through numerical example, the proposed stability conditions are proven to be effective and can include the existing results.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.330-333
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• 2002

Even if the train of subway starts in a certain interval from the origin according to the operation plan. as the number of passenger gets increased during operation. the boarding and getting-off time will increase, and the temporary breakdown happens to the system of train during operation, causing the delay from the operation plan. this leads to the vicious circle of train operation. making the interval of train operation irregular in downtown especially. To solve this problem, we propose the method of advanced algorithm by the actual data relating to the train operation including operation time required between stations, distance between stations. capability of train, and the dwelling time, location and distance between the preceding train and next one. The central train control system adjusts the dwelling time at each station in order to recover the delayed time, and increase the operation speed at the each station. As control algorithm is applied the dwelling time and to increase the speed, the train maintains certain interval after certain amount of time passes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.1
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• pp.85-93
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• 2000

In this paper, the predischarge propagation processes of SF\ulcorner gas stressed by impulse voltages under nonuniform electric field perturbed by a needle protrusion are described. The statistical and formative time-lags and the time interval between leader pulses were investigated on the basis of the predischarge current measured in the gas pressure range of 0.1~0.5 MPa. The predischarge current is closely related to the waveform, amplitude and polarity of applied votages, the gas pressure and the gap geometry. Both the positive and negative predischarge processes in nonuniform electric field develop in a regime of stepwise leader propagation leading to electrical breakdown. The mean of the time interval between leader pulses gives about a factor of 10 higher for the negative than for the positive leader current puls-es. According as the gas pressure increases, the statistical time-lag was almost unchangeable, but the formative time-lag was gradually decreased.

• Journal of Trauma and Injury
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• v.29 no.4
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• pp.139-145
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• 2016

Purpose: The major pelvic trauma results in high mortality with associated fatal other injuries. During early stage of resuscitation, multidisciplinary approach is essential to improve the survival and outcomes. This study aims to report the effect and positive outcome of the trauma team approach on the management of hemodynamically unstable pelvic bone fracture. Methods: This retrospective review included all patients with hemodynamically unstable pelvic bone fracture admitted between March 2007 and December 2015. Patients were divided into group A, which comprised those admitted before the trauma team approach was started, and group B, which comprised those admitted after the approach was started. The advanced trauma life support protocol was followed for all patient. The comparisons between the two groups were based on medical records. Study variables included demographics, initial vital sign, injury severity score, fracture type, and injury mechanism. We analyzed the outcomes in each group with respect to the time interval for doctors' arrival, total length of stay in the emergency department (ED), time interval for computed tomography evaluation, 24-hour mortality, time interval for definitive fixation, and definitive fixation in the time-window of opportunity. Results: Fifty-three patients met the inclusion criteria. No statistically significant differences in demographic data existed between the two groups. The time interval for doctors' arrival (min, $63.09{\pm}50.48$ vs $21.48{\pm}17.75$; p=0.038) and total length of stay in the ED (min, $269.33{\pm}105.96$ vs $115.49{\pm}56.24$; p=0.023) were significantly improved. The 24-hour mortality was not significantly different between the two groups.(%, 14.3 vs 12.0; p=1.000) However, the time interval for definitive fixation and definitive fixation in the time-window of opportunity showed better results. Conclusion: The trauma team approach has positive effects, which include initial resuscitation through multidisciplinary approach and shortening the time interval to definitive fixation, on the management of hemodynamically unstable pelvic bone fracture.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.3
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• pp.447-454
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• 2010

This paper presents multiple fuzzy prediction systems based on an Interval type-2 TSK fuzzy Logic System so that the uncertainty and the hidden characteristics of nonlinear data can be reflected more effectively to improve prediction quality. In proposed method, multiple fuzzy systems are adopted to handle the nonlinear characteristics of data, and each of multiple system is constructed by using interval type-2 TSK fuzzy logic because it can deal with the uncertainty and the characteristics of data better than type-1 TSK fuzzy logic and other methods. For input of each system, the first-order difference transformation method are used because the difference data generated from it can provide more stable statistical information to each system than the original data. Finally, computer simulations are performed to show the effectiveness of the proposed method for two typical time series examples.

• Journal of the Korean Data and Information Science Society
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• v.8 no.2
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• pp.271-276
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• 1997

A dynamic discount approach is proposed for the estimation of the Poisson parameter and the forecasting of the Poisson random variable, where the parameter of the Poisson distribution varies over time intervals. The recursive estimation procedure of the Poisson parameter is provided. Also the forecasted distribution of the Poisson random variable in the next time interval based on the information gathered until the current time interval is provided.

• Journal of Korean Institute of Industrial Engineers
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• v.15 no.2
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• pp.103-108
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• 1989

PERT formulae for the mean and variance of activity time are near exact only over a short interval of the concentration parameter which is defined as the sum of the two shape parameters of the beta distribution. Aiming a better estimation of the mean and variance of activity time, we propose a method of subjectively estimating this concentration parameter via estimating the probability of completing the activity within a specified time interval.

• Journal of the Korean Data and Information Science Society
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• v.7 no.2
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• pp.227-234
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• 1996

The discount survival model is proposed for the application of the Cox model on the analysis of survival data with time-varying effects of covariates. Algorithms for the recursive estimation of the parameter vector and the retrospective estimation of the survival function are suggested. Also the algorithm of forecasting of the survival function of individuals of specific covariates in the next time interval based on the information gathered until the end of a certain time interval is suggested.

• Journal of Electrical Engineering and Technology
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• v.6 no.5
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• pp.713-722
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• 2011

In the present paper, the problem of stability analysis for linear systems with interval time-varying delays is considered. By introducing a new Lyapunov-Krasovskii functional, new stability criteria are derived in terms of linear matrix inequalities (LMIs). Two numerical examples are given to show the superiority of the proposed method.