• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.2
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• pp.825-836
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• 2016

In this paper, a speed-up technique for the non-local means (NLM) image denoising method based on local binary descriptor (LBD) is proposed. In the NLM, most of the computation time is spent on searching for non-local similar patches in the search window. The local binary descriptor which represents the structure of patch as binary strings is employed to speed up the search process in the NLM. The descriptor allows for a fast and accurate preselection of non-local similar patches by bitwise operations. Using this approach, a tradeoff between time-saving and noise removal can be obtained. Simulations exhibit that despite being principally constructed for speed, the proposed algorithm outperforms in terms of denoising quality as well. Furthermore, a parallel implementation on GPU brings NLM-LBD to real-time image denoising.

• Korean System Dynamics Review
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• v.8 no.1
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• pp.117-149
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• 2007

This paper aims to analyse the impact of city-county consolidation on promotion practices of local government employees, using system dynamics approach. The cases employed in this study are Cheongju City and Cheongwon County which reached the referendum stage twice but without success. While the idea of consolidating two neighbouring local governments via a merger sounds enticing, some opponents argue that consolidation may cause some problems on the part of local government employees, emphasizing that consolidation could lengthen actual time period needed for local government employees' promotion. The majority of the existing literature on city-county consolidation, however, tends to describe the most successful cases, focusing on the achievements it has made or the political processes associated with it. With this in mind, this paper attempts to identify the impacts of consolidation on the local government employees' promotion time period, utilizing system dynamics approach. It concludes that consolidation could rather shorten the time period of promotion of local government employees concerned from the long term perspective.

• International Journal of Air-Conditioning and Refrigeration
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• v.10 no.4
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• pp.177-183
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• 2002

A pulsed tracer gas technique is applied to measure the distributions of local mean age and local mean residual-life-time of air in a half-scale experimental chamber, The airflow patterns in the chamber are visualized by a Helium bubble generator for three different exhaust locations. A supply slot is located at the top of a right wall, and an exhaust slot is at either bottom-left (Case 1), bottom-right (Case 2), or top-left (Case 3) location. Results show that the distributions of local mean age and local mean residual-life-time are different from each other, but both of them are closely related to the airflow pattern in the space. Included are discussions on explaining the variations of overall room ventilation effectiveness depending upon airflow rates for three different supply-exhaust configurations.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.6
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• pp.228-234
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• 2002

This paper proposes a real-time application of rationalized Haar transform which is based on the local rationalized Haar transform, local operational matrix and local delay operational matrix. This approach let a general sampling time be used by introducing a scaling factor. In the existing method of orthogonal functions, a major disadvantage is that process signals need to be recorded prior to obtaining their expansions. This paper proposes a novel method of rationalized Haar transform to overcome this shortcoming. And the proposed method is suitable for the analysis of linear systems. The proposed method is expected to the applicable to the adaptive control which demanded to the real-time applications.

• Journal of Ocean Engineering and Technology
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• v.16 no.5
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• pp.66-72
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• 2002

Fracture behaviors of pipes with local wall thinning are very important for the integrity of nuclear power plant. However, effects of local wall thinning on strength and fracture behaviors of piping system were not well studied. Acoustic emission(AE) has been widely used in various fields because of its extreme sensitivity, dynamic detection ability and location of growing defects. In this study, we investigated failure modes of locally wall thinned pipes and AE signals by bending test. From test results, we could be divided four types of failure modes of ovalization, crack initiation after ovalization, local buckling and crack initiation after local buckling. And fracture behaviors such as elastic region, yielding region, plastic deformation region and crack progress region could be evaluated by AE counts, accumulative counts and time-frequency analysis during bending test. The result of the frequency range is expected to be basic data that can inspect plants in real-time.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.1
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• pp.66-72
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• 2016

The aim of this paper is to investigate the characteristics of the signal of local ice load acting on side shell in the bow part due to ice broken by an icebreaker in ice-covered waters. The Korean icebreaking research vessel "ARAON" voyaged to the Arctic Ocean during the summer of 2010, and measurements of local ice load were carried out using several strain gauges. In this study, the time history of measured signals was analyzed and the characteristic values including rising time and half-decaying time were presented using non-dimensional parameters.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.14-24
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• 2020

Real-time performance is to return the exact result value to the correct cycle, or to perform the specified work at a certain cycle. Windows does not support real-time performance, so it supports real-time performance using expensive third parties such as RTX and INtime. This paper aims to support real-time performance of Windows through RTiK, a real-time kernel that operates in the form of a device driver in Windows. In Windows 7, RTiK used a timer using local APIC supported by x86 hardware. However, due to the Kernel Patch Protection (KPP) on Windows 10, it became impossible to use a local APIC timer. Therefore, a timer is implemented to inform the determined cycle using Local APIC IPI, and performance measurement is performed to confirm that the cycle operates normally within the error range. This enables real-time performance on Windows 10.

• Journal of architectural history
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• v.32 no.1
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• pp.73-88
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• 2023

Recently, local studies looking at the 'local(region) as a whole' are gradually increasing. The study of local architectural history is important in that it provides specific information that encompasses the local and the entire and clues to three-dimensionalize the time and space in the local. To infer the 'presentness' of each era, reliable data in various fields are needed. Recently, as many databases (DB) and archives, from the 'National Archives of Korea' to other local archives, have been established and publicized, research resources in the local are growing rapidly in quantity and quality. Nevertheless, it is difficult to comprehensively check the data necessary to study the local architectural history(local architectural history research resources). Against this background, this study confirmed the trend of changes in the archive construction environment and the status and problems of local architectural history research resources in places that currently disclose local history research resources among generalized web-archives. Next, the relationship between the actual research on local architectural history was confirmed through the analysis of existing studies and the data used for Jeju. As a result, local studies, local archives, and local architectural history research agree with recent changes in local research trends, and the degree of archival construction has reached the same level as the available research resources except core data in local architectural history research. However, there is a problem that the density of information that can be used is low because the local architectural history research resources that can be obtained are fragmented because there are no archives and construction entities specialized in local architecture. As each archive has entered the stabilization and upgrading stage, the construction of new archives needs to be reconsidered, but it is time to find a detailed way to link related information quickly and accurately, such as private records, to reduce the gap in information needed in terms of research on local architecture and architecture history.

• Journal of Korea Multimedia Society
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• v.18 no.2
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• pp.158-167
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• 2015

This study presents a new method to improve the speed of high quality volume rendering. We improve the speed of ambient occlusion which is one of the global illumination techniques used in traditional volume visualization. Calculating ambient occlusion takes much time because it determines an illumination value of a sample by integrating opacities of nearby samples. This study proposes an improved method for this by using local statistics such as averages and standard deviations. We calculate local statistics for each volume block, a set of nearby samples, in pre-processing time. In the rendering process, we efficiently determine the illumination value by assuming the density distribution as a normal distribution. As the results, we can generate high quality images that combine ambient occlusion illumination with local illumination in real time.

• Bulletin of the Korean Mathematical Society
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• v.59 no.2
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• pp.507-528
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• 2022

We propose a path integral method to construct a time stepwise local volatility for the stock index market under Dupire's model. Our method is focused on the pricing with the Monte Carlo Method (MCM). We solve the problem of randomness of MCM by applying numerical integration. We reconstruct this task as a matrix equation. Our method provides the analytic Jacobian and Hessian required by the nonlinear optimization solver, resulting in stable and fast calculations.