• 제목/요약/키워드: Practical Similarity

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Sensor fault diagnosis for bridge monitoring system using similarity of symmetric responses

  • Xu, Xiang;Huang, Qiao;Ren, Yuan;Zhao, Dan-Yang;Yang, Juan
    • Smart Structures and Systems
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    • 제23권3호
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    • pp.279-293
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    • 2019
  • To ensure high quality data being used for data mining or feature extraction in the bridge structural health monitoring (SHM) system, a practical sensor fault diagnosis methodology has been developed based on the similarity of symmetric structure responses. First, the similarity of symmetric response is discussed using field monitoring data from different sensor types. All the sensors are initially paired and sensor faults are then detected pair by pair to achieve the multi-fault diagnosis of sensor systems. To resolve the coupling response issue between structural damage and sensor fault, the similarity for the target zone (where the studied sensor pair is located) is assessed to determine whether the localized structural damage or sensor fault results in the dissimilarity of the studied sensor pair. If the suspected sensor pair is detected with at least one sensor being faulty, field test could be implemented to support the regression analysis based on the monitoring and field test data for sensor fault isolation and reconstruction. Finally, a case study is adopted to demonstrate the effectiveness of the proposed methodology. As a result, Dasarathy's information fusion model is adopted for multi-sensor information fusion. Euclidean distance is selected as the index to assess the similarity. In conclusion, the proposed method is practical for actual engineering which ensures the reliability of further analysis based on monitoring data.

실질적 유사성 판단을 위한 가중치 활용과 질적 분석의 관계 (A Study on the Relationship between Weighted Value and Qualitative Standard in Substantial Similarity)

  • 김시열
    • 한국소프트웨어감정평가학회 논문지
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    • 제15권1호
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    • pp.25-35
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    • 2019
  • 우리나라에서 컴퓨터프로그램의 실질적 유사성 여부 판단은 정량적인 유사도를 산출하여 그 결과를 활용하는 방식이 일반적으로 이용된다. 실질적 유사성은 유사한 부분의 양과 질을 고려하여 판단되어야 하는데, 실무에서는 정량적인 유사도 계산 과정에서 가중치를 곱함으로써 유사한 부분의 질을 고려하는 모습을 보인다. 그런데 실질적 유사성 판단과 관련하여 유사한 부분의 양적, 질적인 고려는 동일한 지위에서 순차적으로 이루어져야 한다는 본질적 특징을 고려할 때, 현재와 같은 실무 방식은 적절하다고 할 수 없다. 이에 이와 같은 가중치 활용의 문제를 지적하고, 실질적 유사성 판단을 위한 유사 부분의 질적 평가는 정량적 유사도 판단에 후행하여 그와 동일한 지위에서 이루어져야 함을 제시 및 이를 위한 적절한 실무적 방안을 제언하였다.

The modified Similarity Theory of Movable-Bed River Model

  • Seo, Il-Won;Cheong, Tae-Sung;Kim, Young-Han
    • Korean Journal of Hydrosciences
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    • 제10권
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    • pp.1-15
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    • 1999
  • A relaxed similarity theory which can be applied to river madels with movable beds is established by modifying existing theory by Einstein and Chien(1954). Experimental data collected from river models with movable beds were used to evaluate the applicability of the proposed theory. Effects of similarity of flow. $\Delta$F$\Delta$M, and similarity of sediment movement, $\Delta$$F_s$, were examined by analyzing the behavior of total river-bed change. The results show that the smaller $\Delta$F$\Delta$M or $\Delta$$F_s$ is, respectively, the larger total sedimentation is. The modified similarity theory established in this study would be useful and practical whenever it is impossible or very difficult to satisfy strict theoretical requirments concerning the river model experiments with movable beds.

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Collaborative Similarity Metric Learning for Semantic Image Annotation and Retrieval

  • Wang, Bin;Liu, Yuncai
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권5호
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    • pp.1252-1271
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    • 2013
  • Automatic image annotation has become an increasingly important research topic owing to its key role in image retrieval. Simultaneously, it is highly challenging when facing to large-scale dataset with large variance. Practical approaches generally rely on similarity measures defined over images and multi-label prediction methods. More specifically, those approaches usually 1) leverage similarity measures predefined or learned by optimizing for ranking or annotation, which might be not adaptive enough to datasets; and 2) predict labels separately without taking the correlation of labels into account. In this paper, we propose a method for image annotation through collaborative similarity metric learning from dataset and modeling the label correlation of the dataset. The similarity metric is learned by simultaneously optimizing the 1) image ranking using structural SVM (SSVM), and 2) image annotation using correlated label propagation, with respect to the similarity metric. The learned similarity metric, fully exploiting the available information of datasets, would improve the two collaborative components, ranking and annotation, and sequentially the retrieval system itself. We evaluated the proposed method on Corel5k, Corel30k and EspGame databases. The results for annotation and retrieval show the competitive performance of the proposed method.

다중 특징 결합과 유사도 공간을 이용한 SVM 기반 얼굴 검증 시스템 (An SVM-based Face Verification System Using Multiple Feature Combination and Similarity Space)

  • 김도형;윤호섭;이재연
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제31권6호
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    • pp.808-816
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    • 2004
  • 본 논문에서는 다중 특징 결합과 유사도 공간을 이용한 실제적인 온라인 얼굴 검증 시스템을 구현하는 방법을 제안한다. 얼굴 검증에서의 주요 쟁점은 다양한 얼굴 형상 변화의 처리이다. 이러한 변화는 단지 한가지 특징만으로는 해결되기 어렵다. 따라서 얼굴 형상에 있어서의 다양한 변화를 처리하기 위해서 상호보완적인 특징들의 결합이 필요하다. 이러한 관점에서 우리는 다중 주성분 분석과 에지 분포에 기반 한 특징 추출 방법을 제안한다. 이러한 특징들은 다수의 간단한 유사도 측정 방법들로 형성된 새로운 intra-person/extra-person 유사도 공간으로 사상되고, 최종적으로 Support Vector Machine에 의해 평가된다. 실제적인 대용량 데이터 베이스로 실험한 결과, equal error rate 0.029의 결과를 나타내었고, 이는 많은 실제 응용제품에도 충분히 팩용 가능한 수준이다.

온라인 커뮤니티에서 조직시민행동의 영향요인이 지식공헌에 미치는 영향 (The Effect of Antecedents of Organizational Citizenship Behavior on Knowledge Contribution in Online Communities)

  • 김경규;신호경;장항배;공영일
    • 지식경영연구
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    • 제10권2호
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    • pp.105-119
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    • 2009
  • This study addresses the following questions : how does organization citizenship behavior(OCB) affect knowledge contribution in online communities? does the antecedents of OCB, cohesiveness and affection similarity, influence knowledge contribution in online communities? In order to test our hypotheses with an empirical study, we have conducted a survey which resulted in 192 valid response in the final sample. The PLS analysis results indicate that OCB affects knowledge contribution and coherence and affection similarity of online community users have influence on OCB. Further, knowledge contribution is influenced by community users' affection similarity. Practical implications of these findings and future research implications are also discussed.

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Using Fuzzy Rating Information for Collaborative Filtering-based Recommender Systems

  • Lee, Soojung
    • International journal of advanced smart convergence
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    • 제9권3호
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    • pp.42-48
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    • 2020
  • These days people are overwhelmed by information on the Internet thus searching for useful information becomes burdensome, often failing to acquire some in a reasonable time. Recommender systems are indispensable to fulfill such user needs through many practical commercial sites. This study proposes a novel similarity measure for user-based collaborative filtering which is a most popular technique for recommender systems. Compared to existing similarity measures, the main advantages of the suggested measure are that it takes all the ratings given by users into account for computing similarity, thus relieving the inherent data sparsity problem and that it reflects the uncertainty or vagueness of user ratings through fuzzy logic. Performance of the proposed measure is examined by conducting extensive experiments. It is found that it demonstrates superiority over previous relevant measures in terms of major quality metrics.

New Similarity Measures of Simplified Neutrosophic Sets and Their Applications

  • Liu, Chunfang
    • Journal of Information Processing Systems
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    • 제14권3호
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    • pp.790-800
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    • 2018
  • The simplified neutrosophic set (SNS) is a generalization of fuzzy set that is designed for some practical situations in which each element has truth membership function, indeterminacy membership function and falsity membership function. In this paper, we propose a new method to construct similarity measures of single valued neutrosophic sets (SVNSs) and interval valued neutrosophic sets (IVNSs), respectively. Then we prove that the proposed formulas satisfy the axiomatic definition of the similarity measure. At last, we apply them to pattern recognition under the single valued neutrosophic environment and multi-criteria decision-making problems under the interval valued neutrosophic environment. The results show that our methods are effective and reasonable.

Using User Rating Patterns for Selecting Neighbors in Collaborative Filtering

  • Lee, Soojung
    • 한국컴퓨터정보학회논문지
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    • 제24권9호
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    • pp.77-82
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    • 2019
  • Collaborative filtering is a popular technique for recommender systems and used in many practical commercial systems. Its basic principle is select similar neighbors of a current user and from their past preference information on items the system makes recommendations for the current user. One of the major problems inherent in this type of system is data sparsity of ratings. This is mainly caused from the underlying similarity measures which produce neighbors based on the ratings records. This paper handles this problem and suggests a new similarity measure. The proposed method takes users rating patterns into account for computing similarity, without just relying on the commonly rated items as in previous measures. Performance experiments of various existing measures are conducted and their performance is compared in terms of major performance metrics. As a result, the proposed measure reveals better or comparable achievements in all the metrics considered.

유사도 측정 데이터 셋과 쓰레숄드 (Practical Datasets for Similarity Measures and Their Threshold Values)

  • 양병주;심준호
    • 한국전자거래학회지
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    • 제18권1호
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    • pp.97-105
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    • 2013
  • 방대한 량의 전자상거래 데이터 객체를 다루는데 같거나 유사한 객체들을 찾는 유사도 측정은 중요하다. 객체간 유사도 측정은 객체 쌍의 유사도 측정값을 비교하므로 객체 량이 많아질수록 오랜 시간이 걸린다. 최근의 여러 유사도 측정 연구에선 이를 더 효율적으로 수행하는 기법을 제시하고 실제 데이터 셋에서 그 성능을 평가해왔다. 본 논문에서는 이들 연구에서 사용하는 데이터 셋의 특성과 실험에서 사용되는 쓰레숄드 값이 가지는 의미에 대해 분석해본다. 이러한 분석은 새로운 유사도 측정 기법의 성능 평가 실험의 참조 기준을 제시하는 역할을 한다.