• Journal of KSNVE
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• v.8 no.6
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• pp.1037-1042
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• 1998

This paper discusses the dependence of the convergence rate on the acoustic error path in these popular algorithms and introduces new algorithms which increase the convergence region regardless of the time-delay in the acoustic error path. We also Propose a novel control algorithm (AFC/CAFC) for tonal noise cancellation. The proposed algorithm estimates the magnitude and phase of the tonal noise. The algorithm uses the steepest descent method for the phase/magnitude estimation. Performances of tile CAFC algorithm are presented in comparison with those by the AFC algorithm based on computer simulations and experiments.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.670-677
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• 1998

Many of the adaptive noise control systems utilize a form of the least mean square (LMS) algorithm. In the active control of noise, it is common practice to locate an error microphone far from the control source to avoid the near-field effects by evanescent waves. Such a distance between the control source and the error microphone makes a certain level of time-delay inevitable and, hence, may yield undesirable effects on the convergence properties of control algorithms such as filtered-x LMS. This paper discusses the dependence of the convergence rate on the acoustic error path in these popular algorithms and introduces new algorithms which increase the convergence region regardless of the time-delay in the acoustic error path. Performances of the new LMS algorithms are presented in comparison with those by the conventional algorithms based on computer stimulations and experiments.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.310-313
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• 2000

This paper presents a new scheduling method for ILP processing called NHS(Novel Hybrid Scheduling). It concerns not only exploiting as much ILP as possible like other state-of-the-art scheduling scheme, but also choosing the most important instructions among many ready-to-execute instructions to processors in order to reduce the execution time under limited hardware resource. At the heart of NHS is a conception called CCP(Complex Critical Path), an extension of CP(Critical Path). By using CCP, compiler not only can get a global information of the whole program to extract ILP, but also can collecting data dependence information and control flow information. The paper also presents the simulation results, to date, of our attempts to study the NHS scheduling method. The results indicate good potential for this scheduling method.

• Proceedings of the KIEE Conference
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• 2001.10a
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• pp.100-103
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• 2001

The magnetic force calculation methods, the Maxwell's stress tensor method, virtual work method, and nodal force method are reviewed. The methods are applied to the magnetic force calculation of 2D linear and nonlinear Problems. As the results the convergence of the methods as the number of elements increases, accuracy of the methods, and integral path dependence of the methods are discussed. Finally some recommendations on the usage of the methods, including the determination of the integral path, are given.

• Journal of Contemporary Eastern Asia
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• v.21 no.2
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• pp.13-26
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• 2022

This study explores the following research question to address issues linked to emotions, identity, and institutions: how has the cult (institution) of the three Kims affected North Koreans' strong sense of nationalism (emotion), which is based on their Juche ideology (identity)? This paper investigates four fundamental elements of historical institutionalism: time boundedness, path dependency, institutional changes, and the shadow of the past. First, time boundedness illustrates how culture and education have been used to build trust and loyalty in the general public to construct individual and family cults. Second, path dependence reveals how the Songbun system has resulted in strong nationalism throughout Rodongdang's institutionalization. Third, institutional changes highlight the significance of age divides, as different age groups do not always support the three Kims' cult. Finally, the shadow of the past helps us understand the primary processes for generating mass ardent nationalism in the form of powerful impulses for self-sacrifice.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.1A
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• pp.1-7
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• 2011

Cell Capacity and cell layout are strongly dependent on the up-link interference caused by out-of-cell mobiles. Accurate prediction of the propagation path loss from out-of-cell mobiles is essential to achieve system designs that minimize the infrastructure required for a given quality of service (QOS). Less accurate predictions can be expected to yield designs requiring the use of a greater number of base stations. In order to quantify the dependence of infrastructure on prediction accuracy, this paper considers the cellular systems, LOS (line of sight) cells along a road or highway.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.5
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• pp.1303-1315
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• 2012

In the draft of the IEEE 802.11s standard, a tree topology is established by the proactive tree-building mode of the Hybrid Wireless Mesh Protocol (HWMP). It is used for cases in which the root station (e.g., gateway) is an end point of the majority of the data connections. In the tree topology, the root or central stations (e.g., parent stations) are connected to the other stations (e.g., leaves) that are one level lower than the central station. Such mesh stations are likely to suffer heavily from contention in bottleneck links when the network has a high traffic load. Moreover, the dependence of the network on such stations is a point of vulnerability. A failure of the central station (e.g., a crash or simply going into sleep mode to save energy) can cripple the whole network in the tree topology. This causes performance degradation for end-to-end transmissions. In a connected mesh topology where the stations having two or more radio links between them are connected in such a way that if a failure subsists in any of the links, the other link could provide the redundancy to the network. We propose a scheme to utilize this characteristic by organizing the network into concentric tiers around the root mesh station. The tier structure facilitates path recovery and congestion control. The resulting mode is referred to as Tier-based Proactive Path Selection Mode (TPPSM). The performance of TPPSM is compared with the proactive tree mode of HWMP. Simulation results show that TPPSM has better performance.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.222-235
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• 2019

Since Fukushima nuclear disaster occurred in 2011, the nuclear energy policy of the international society has been in recession. However, In Korea, the nuclear-friendly policy had remained and even expanded over the last 60 years until the Park Geun-hye government. In other words, there was the path dependence of nuclear energy policy. Since the Moon Jae-in government that pledged to perform nuclear phase-out policy in 2017 was inaugurated, the nuclear-friendly policy began to swerve from the course of path dependence. Based on the mai logic of historical institutionalism, this study looked into the change of Korean nuclear policy by before and after the Fukushima nuclear accident. As the result of this research, the external situation of Fukushima Nuclear Accident became a critical turning point and led to a change in the government's policy on nuclear power. From an institutional perspective, it influenced the paradigm of nuclear power policy, policy decision structure, and laws of nuclear power. From a doer's perspective, it influenced political idea and social acceptability. Since Moon Jae-in government was inaugurated in 2017, nuclear phase-out policy has secured its institutional foundation and nuclear power policy has basically changed from nuclear-friendly policy to nuclear phase-out policy. Therefore, the energy policy of Moon Jae-in government gets out of the nuclear power based path dependency that previous governments pursued, keeps punctuated equilibrium, and changes to renewable energy oriented policy.

• Journal of Sensor Science and Technology
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• v.6 no.2
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• pp.95-105
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• 1997

A new open-loop signal processing technique of digital phase tracking is known to have a Potential to solve the problems in the open-loop processor such as limited dynamic range, dependence on the optical intensity fluctuations, and dependence on gain fluctuations of signal path. But new problems with digital phase tracking must be solved before it can be a useful signal processing method. In this paper, barriers to the success of the digital phase tracking such as harmonics content, phase difference, amplitude variations of the phase modulation(PM) signal, bandwidth limit of the signal path, and the implementation of the mixer, are pointed out and their effects on the performance of the signal processor are analyzed to calculate the requirements of the signal processor for $1{\mu}rad$-grade FOG.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.2
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• pp.111-117
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• 2016

The primary concern of this research is to examine the phonon mean free path (MFP) spectrum contribution to heat conduction. The size effect of materials is determined by phonon MFP, and the size effect appears when the phonon MFP is similar to or less than the characteristic length of materials. Therefore, knowledge of the phonon MFP is essential to increase or decrease the heat conduction of a material for engineering applications, such as micro/nanosystems. In this study, frequency dependence of the phonon transport is considered using the Boltzmann transport equation based on a full phonon dispersion model. Additionally, the phonon MFP spectrums of in-plane and out-of-plane heat transport are investigated by varying the film thickness of the silicon layer from 41 nm to 177 nm. This will increase the understanding of anisotropic heat conduction in a SOI (Silicon-on-Insulator) transistor.