• Journal of Information Processing Systems
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• 제20권2호
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• pp.185-199
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• 2024

In this paper, an improved automated spectral clustering (IASC) algorithm is proposed to address the limitations of the traditional spectral clustering (TSC) algorithm, particularly its inability to automatically determine the number of clusters. Firstly, a cluster number evaluation factor based on the optimal clustering principle is proposed. By iterating through different k values, the value corresponding to the largest evaluation factor was selected as the first-rank number of clusters. Secondly, the IASC algorithm adopts a density-sensitive distance to measure the similarity between the sample points. This rendered a high similarity to the data distributed in the same high-density area. Thirdly, to improve clustering accuracy, the IASC algorithm uses the cosine angle classification method instead of K-means to classify the eigenvectors. Six algorithms-K-means, fuzzy C-means, TSC, EIGENGAP, DBSCAN, and density peak-were compared with the proposed algorithm on six datasets. The results show that the IASC algorithm not only automatically determines the number of clusters but also obtains better clustering accuracy on both synthetic and UCI datasets.

• 수산경영론집
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• 제14권2호
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• pp.1-14
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• 1983

This paper considers a classification of the 88 islands located at Kyong-nam area in Korea, using by examples of 12 components of the islands. By means of principal component analysis 2 principle components were extracted, which explained a total of 73.7% of the variance. Using an eigen variable criterion (λ>1), no further principle components were discussed. Principal component 1 and 2 explained 63.4% and 10.3% of the total variance respectively, The representation of the unrelated factor scores along the first and second principal axes produced a new information with respect to the classification of the islands. Based upon the representation, 88 islands were classified into 6 groups i. e. A, B, C, D, E, and F according to similarity of the components among them in this paper. The "Group F" belongs to a miscellaneous assortment that does not fit into the logical category. category.

• 산업경영시스템학회지
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• 제16권27호
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• pp.83-89
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• 1993

In order to model the Group Technology Problem three formulations are used, that is, generally the following formulations are used: (1) Matrix formulation, (2) Mathematical programming formulation, (3) Graph formulation. In the case of Matrix formulation, it is difficult to discribe the situation using the multi-job machine. But this paper proposed the model of Group Technology using the multi-job machin, taking the method of making practical application of principle of similarity coefficient.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.53-56
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• 2003

In this paper, we propose a new method which generates the trajectory of the mouth shape for the characters by the user inputs. It is based on the character at a basis syllable and can be suitable to the mouth shape generation. In this paper, we understand the principle of the Korean language creation and find the similarity for the form of the mouth shape and select it as a basic syllable. We also consider the articulation of this phoneme for it and create a new mouth shape trajectory and apply at face of an 3D avatar.

• Molecules and Cells
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• 제25권2호
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• pp.163-171
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• 2008

The genus Cynodon comprises ten species. The objective of this study was to evaluate the genetic diversity of Korean bermudagrasses at the morphological, cytological and molecular levels. Morphological parameters, the nuclear DNA content and ploidy levels were observed in 43 bermudagrass ecotypes. AFLP markers were evaluated to define the genetic diversity, and chromosome counts were made to confirm the inferred cytotypes. Nuclear DNA contents were in the ranges 1.42-1.56, 1.94-2.19, 2.54, and 2.77-2.85 pg/2C for the triploid, tetraploid, pentaploid, and hexaploid accessions, respectively. The inferred cytotypes were triploid (2n = 3x = 27), tetraploid (2n = 4x = 36), pentaploid (2n = 5x = 45), and hexaploid (2n = 6x = 54), but the majority of the collections were tetraploid (81%). Mitotic chromosome counts verified the corresponding ploidy levels. The fast growing fine-textured ecotypes had lower ploidy levels, while the pentaploids and hexaploids were coarse types. The genetic similarity ranged from 0.42 to 0.94 with an average of 0.64. UPGMA cluster analysis and principle coordinate analysis separated the ecotypes into 6 distinct groups. The genetic similarity suggests natural hybridization between the different cytotypes, which could be useful resources for future breeding and genetic studies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권1호
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• pp.257-271
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• 2016

The Structural SIMilarity (SSIM) index is one of the most widely-used methods for perceptual image quality assessment (IQA). It is based on the principle that the human visual system (HVS) is sensitive to the overall structure of an image. However, it has been reported that indices predicted by SSIM tend to be biased depending on the type of distortion, which increases the deviation from the main regression curve. Consequently, SSIM can result in serious performance degradation. In this study, we investigate the aforementioned phenomenon from a new perspective and review a constant that plays a big role within the SSIM metric but has been overlooked thus far. Through an experimental study on the influence of this constant in evaluating images with SSIM, we are able to propose a new solution that resolves this issue. In the proposed IQA method, we first design a system to classify different types of distortion, and then match an optimal constant to each type. In addition, we supplement the proposed method by adding color perception-based structural information. For a comprehensive assessment, we compare the proposed method with 15 existing IQA methods. The experimental results show that the proposed method is more consistent with the HVS than the other methods.

• 한국관개배수논문집
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• 제17권2호
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• pp.17-27
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• 2010

In order to manage the water quality in reservoir, it is necessary to understand the temporal and spatial variation of reservoirs and to classify the reservoirs. In this research, agricultural reservoirs are classified according to physical characteristics (depth, residence time, shape of the reservoir etc) and water quality using multivatriate analysis (PCA and CA). CA (Cluster Analysis) method classify reservoirs into several groups as a similarity of the reservoirs, but it is difficult to indicate a full list to the one table. In case of PCA (Principle Component Analysis) method, it has the advantage for the classification on the reservoirs depending on the water quality similarity and also it is useful to analyze the relationship between related factors through correlation analysis. However PCA is limited to classify into several groups based on the characteristics of the reservoirs and each user should be classified as randomly subjective according to the relative position of the reservoir in the figure. In conclusions, compared to conventional reservoirs classification methods, both CA and PCA methods are considered to be a classification method that describes the nature of the reservoir well, but classification results has a restriction on use, so further research will be needed to complement.

• 한국ITS학회 논문지
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• 제19권6호
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• pp.14-25
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• 2020

본 연구는 교통카드자료 이용하여 수도권 지하철을 통행하는 승객의 경로선택의 합리성에 대한 평가를 시행하는 방법론을 제안한다. 사용자 경로선택의 합리성은 최적의 경로를 선택한다는 기본원리로서 확정성과 유사성으로 구분한다. 확정성은 승객이 선택한 경로는 시스템적 최적경로와 일치하는 정도이다. 유사성은 시스템적 최적경로와 유사하게 파악되는 정도이다. 합리성을 판단하는 기법으로 K경로탐색기법을 이용하여 경로를 열거하는 방법을 구축하였다. 유사성 내에서 확정성을 파악하기 위하여 민자운영기관의 환승단말기 Tag 정보를 활용하였다. 따라서 유사성에서 승객이 선택한 최적경로는 Tag를 경유한 경로와 동일하다는 개념을 적용하였다. 연구결과 최적경로(K=1)로 나타나는 확정성은 90.4(%), K=(2-10)으로 나타나는 유사성은 7.9(%)로서 총 98.3(%)의 수도권 지하철 통행이 합리적으로 설명된다고 평가하였다. 비합리적 통행 1.7(%)는 사용자 다양성을 고려하여 나타나는 설명되지 않는 에러항으로 평가된다고 파악하였다.

• 조명전기설비학회논문지
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• 제23권4호
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• pp.62-71
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• 2009

본 논문에서는 주성분 분석 기법에 의한 BLDC 전동기의 고장진단 알고리즘과 임베디드 타입의 실시간 고장진단 시스템을 구현하였다. 우선 오프라인 상태에서 제안된 고장진단 알고리즘을 검증하기 위해 BLDC 고장진단 실험장치를 구현한 후 LabVIEW 프로그램에 의해 다양한 고장 데이터를 취득하였다. 취득된 데이터는 신호특성에 맞는 전 처리과정을 수행한 후 주성분분석 기법에 의해 고장특성을 나타내는 특징을 추출하고 최종적으로 BLDC 전동기의 진단은 유클리디안 거리 유사도 방법에 의해 수행된다. 이러한 결과를 바탕으로 임베디드 타입의 실시간 BLDC 고장진단 시스템을 구현하였다. 제안된 방법은 다양한 실험을 통하여 성능을 평가하였다.

• 패션비즈니스
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• 제16권2호
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• pp.124-137
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• 2012

This study aims to identify the meaning and formation cause of a style, and the essential elements of style formation, through psychobiological research as well as an analysis of the designs of Iris Van Herpen, a fashion designer, who in just 6 years has developed into a world-renowned new designer. As a result, it has been found that the psychobiological causes to form a style stem from the action of 'long-term memory', which is consolidated by 'selective attention', 'perceptional subjectivity', the principle of the 'neuron's connection specificity and invariance', and the principle of a 'neuronal signal's unilateral flow'. With such action, Herpen could develop her own original composition techniques. The formative shapes created by such composition techniques are characterized by enumeration, superposition, and hanging. The study has also found that the essential elements for a designer to be able to form his/her own style include 'aesthetic originality' in which the designer views the property of a thing from his/her inherent perspective, and finds the uniqueness from the thing that only he/she can express, 'technical differences' that are creative and original, and 'formative specificity' that is summarized into one property through an impressive shape.