• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.4
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• pp.156-162
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• 2006

Transmission zones can be defined based on LMPs. Each zone consists of nodes with similar LMPs, and zonal price is determined by average nodal prices in each zone.[1] Network reduction is still important for the analysis of zonal systems under electricity market environments, even though the computing capability of computer system can deal with entire power systems. The Similarity Index is a good performance measure for the network reduction.[2] It can be applied to the network reduction between zones categorized by the nodal prices. This paper deals with a novel network reduction method between zones based on the similarity Index. Line admittances of reduced network were determined by using the least square method. The proposed method was verified by IEEE 39 bus test system.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.1
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• pp.71-81
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• 2017

In this study, a series of full-scale extrapolation procedures based on the Granville's similarity scaling method, which was employed by Schultz (2007), is modified and then applied to compare the resistance performance between two different anti-fouling coatings. As an analysis example, the low frictional AF coating based on a novel skin-friction reducing polymer named FDR-SPC (Frictional Drag Reduction Self-Polishing Copolymer), which had been invented by the present author, is employed. The low frictional coating, which gives 25.4% skin frictional reduction in lab test, is estimated to give 18.2% total resistance reduction for a 176k DWT bulk carrier.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.207-210
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• 2005

The Similarity Index[1] is a good Performance measure for the network reduction. It can be applied to the network reduction In the zone categorized by the nodal prices. This paper deals with a zonal reduction method based on the similarity indices. The proposed method was verified by IEEE 39 bus test system.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.510-520
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• 2019

To investigate the morphology characteristics of air layer in the air cavity, a numerical method with the combination of RANS equations and VOF two-phase-flow model is proposed for a plate with air cavity. Based on the model above, the dynamic and developmental process of air layer in the air cavity is studied. Numerical results indicate that the air layer in the plate's air cavity exhibits the dynamic state of morphology and the wavelength of air layer becomes larger with the increasing speed. The morphology of air layer agrees with the Froude similarity law and the formation of the air layer is not affected by the parameters of the cavity, however, the wave pattern of the air layer is influenced by the parameters of the cavity. The stable air layer under the air cavity is important for the resistance reduction for the air layer drag reduction.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.401-404
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• 2002

In general, speech coding methods are classified into the following three categories: the waveform coding, the source coding and the hybrid coding. In this paper, First, the reference waveform is detected after searching the pitch period by NAMDF similarity and similarity between the reference waveform and the waveform each pitch period. It made a decision whether the waveform is compressed with the threshold of similarity. If the waveform is compressed only magnitude and pitch information is transmitted into the input of G.723.1 vocoder. Performing through the G.723.1 vocoder, the waveform is restored with the magnitude and pitch information by PSOLA synthesis method. The result of simulation with proposed algorithm has a 31% reduction of bit rate than the standard 5.3kbps G.723.1 ACELP vocoder.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2018.11a
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• pp.73-76
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• 2018

A Gaussian noise is caused by surrounding environment or channel interference when transmitting image. The noise reduces not only image quality degradation but also high-level image processing performance. The Non-Local Means (NLM) filter finds similarity in the neighboring sets of pixels to remove noise and assigns weights according to similarity. The weighted average is calculated based on the weight. The NLM filter method shows low noise cancellation performance and high complexity in the process of finding the similarity using weight allocation and neighbor set. In order to solve these problems, we propose an algorithm that shows an excellent noise reduction performance by using Summed Square Image (SSI) to reduce the complexity and applying the weighting function based on a cosine Gaussian kernel function. Experimental results demonstrate the effectiveness of the proposed algorithm.

• Journal of Korean Society for Quality Management
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• v.20 no.2
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• pp.109-117
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• 1992

An inspection task largely can be seen as a job divided up into a series of visual search and classification subtasks. In these subtasks, an Inspector must performs to compare the standard references proposed in visual environments and recalled in his memory with the visual stimuli to be inspected. It means that the judgement of similarity should be demanded on inspection tasks. Therefore, the inspector's ability for the judgement of similarity and the difference similarity between inspection materials are important factors to effect on performances in inspection tasks. In this paper, to analysis the effect of these factors on inspection time, an inspection task is designed and suggested by means of computer simulator. Especially, the skin conductance responses(SCR) of subjects are measured to evaluate the complexity of tasks due to the difference of similarity between materials. In the results of experiment, the more similar or different the difference of similarity between materials is, the shorter the inspection time is because of the reduction of task complexity. And, When the inspector's cognition for similarity between materials is consistanct, the inpsection time is improved. Concludingly, the consistency of reponses for similarity judgement becomes a measurement to present the performance levels. And the information of inspection time that due to the difference of similarity between materials must be considered in planning and scheduling inspection tasks.

• The Research Journal of the Costume Culture
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• v.22 no.5
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• pp.743-759
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• 2014

The purpose of this study is to identify the antecedents of consumers' decision postponement on purchasing fast fashion brands. Ongoing search behavior, overchoice confusion, and similarity confusion were considered as antecedents. It was hypothesized that ongoing search behavior influences decision postponement both directly and indirectly through overchoice confusion and similarity confusion. Data were gathered by surveying university students in Seoul, using convenience sampling. Three hundred five questionnaires were used in the statistical analysis, which were exploratory factor analysis using SPSS and confirmatory factor analysis and path analysis using AMOS. Factor analysis proved that ongoing search behavior, overchoice confusion, similarity confusion, and decision postponement were uni-dimensions. Tests of the hypothesized path proved that ongoing search behavior influences decision postponement indirectly through overchoice confusion. In addition, similarity confusion influences decision postponement. The results suggest some confusion reduction strategies for marketers of fast fashion brands. Suggestions for future study are also discussed.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.153-154
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• 2008

This paper presents a window-based software package for the education and training for the reduction of power system by using locational marginal price (LMP), clustering, and similarity indices of each bus. The developed package consists of three modules: 1) the LMP module, 2) the Clustering module and 3) the Reduction module. Each module has a separated and interactive interface window. First of all, LMPs are created in the LMP module, and then the Clustering module carries out clustering based on the results of the LMP module. Finally, groups created in this Clustering module are reduced by using the similarity indices of each bus. The developed package displays a variety of tables for results of the LMPs of base network, voltages, phases and power flow of reduced network so that the user can easily understand the reduction of network. To demonstrate the performance of the developed package, it is tested for the IEEE 39-bus power system.

• The Journal of the Acoustical Society of Korea
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• v.38 no.3
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• pp.314-319
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• 2019

Computing chromagram similarity is indispensable in constructing cover song identification system. This paper proposes a code-based chromagram similarity to reduce the computational and the storage costs for cover song identification. By learning a song-specific codebook, a chromagram sequence is converted into a code sequence, which results in the reduction of the feature storage cost. We build a lookup table over the learned codebooks to compute chromagram similarity efficiently. Experiments on two music datasets were performed to compare the proposed code-based similarity with the conventional one in terms of cover song search accuracy, feature storage, and computational cost.