• Title/Summary/Keyword: nearest neighbor

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Speed Improvement of Nearest Neighbor Search Algorithm using Dimension Compression (차원 압축을 통한 최근접점 탐색 알고리즘의 속도 개선)

  • 강혜란;남현우;위영철
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.10b
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    • pp.517-519
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    • 2001
  • 본 논문에서는 최근접점 탐색 알고리즘(Nearest Neighbor Searching)을 사용하여 고차원에서 질의점을 효과적으로 찾기 위한 방안을 제안한다. 최근접점 탐색에서 정확도와 실행속도는 반비례 관계를 가지며 기존에 제안된 최근접점 탐색 알고리즘의 경우, 차원이 증가할수록 탐색 시간이 기하급수적으로 증가하게 되어 고차원에서 질의점을 탐색할 경우 실행시간이 현저하게 길어진다. 최근접점 탐색을 실세계에서 적용할 경우 정확도도 중요하지만 실행 속도 또한 중요하다. 이 점을 감안하여 본 논문에서는 고차원 데이터를 저차원으로 압축하여 질의점을 탐색하고 압축 이전과 이후의 결과를 비교한 후, 이를 통해 정확성과 실행속도의 관계를 분석한다. 본 논문에서는 제안한 차원 압축을 이용할 경우 정확성이 중요한 요소가 아닌 탐색에서 상당한 실행속도가 개선될 것으로 기대된다.

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Cross platform classification of microarrays by rank comparison

  • Lee, Sunho
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.2
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    • pp.475-486
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    • 2015
  • Mining the microarray data accumulated in the public data repositories can save experimental cost and time and provide valuable biomedical information. Big data analysis pooling multiple data sets increases statistical power, improves the reliability of the results, and reduces the specific bias of the individual study. However, integrating several data sets from different studies is needed to deal with many problems. In this study, I limited the focus to the cross platform classification that the platform of a testing sample is different from the platform of a training set, and suggested a simple classification method based on rank. This method is compared with the diagonal linear discriminant analysis, k nearest neighbor method and support vector machine using the cross platform real example data sets of two cancers.

An Anomaly Detection Algorithm for Cathode Voltage of Aluminum Electrolytic Cell

  • Cao, Danyang;Ma, Yanhong;Duan, Lina
    • Journal of Information Processing Systems
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    • v.15 no.6
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    • pp.1392-1405
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    • 2019
  • The cathode voltage of aluminum electrolytic cell is relatively stable under normal conditions and fluctuates greatly when it has an anomaly. In order to detect the abnormal range of cathode voltage, an anomaly detection algorithm based on sliding window was proposed. The algorithm combines the time series segmentation linear representation method and the k-nearest neighbor local anomaly detection algorithm, which is more efficient than the direct detection of the original sequence. The algorithm first segments the cathode voltage time series, then calculates the length, the slope, and the mean of each line segment pattern, and maps them into a set of spatial objects. And then the local anomaly detection algorithm is used to detect abnormal patterns according to the local anomaly factor and the pattern length. The experimental results showed that the algorithm can effectively detect the abnormal range of cathode voltage.

Real-time Face Detection and Recognition using Classifier Based on Rectangular Feature and AdaBoost (사각형 특징 기반 분류기와 AdaBoost 를 이용한 실시간 얼굴 검출 및 인식)

  • Kim, Jong-Min;Lee, Woong-Ki
    • Journal of Integrative Natural Science
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    • v.1 no.2
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    • pp.133-139
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    • 2008
  • Face recognition technologies using PCA(principal component analysis) recognize faces by deciding representative features of faces in the model image, extracting feature vectors from faces in a image and measuring the distance between them and face representation. Given frequent recognition problems associated with the use of point-to-point distance approach, this study adopted the K-nearest neighbor technique(class-to-class) in which a group of face models of the same class is used as recognition unit for the images inputted on a continual input image. This paper proposes a new PCA recognition in which database of faces.

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Study on the fast nearest-neighbor searching classifier using distance approximation (거리 근사를 이용하는 고속 최근 이웃 탐색 분류기에 관한 연구)

  • 이일완;채수익
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.2
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    • pp.71-79
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    • 1997
  • In this paper, we propose a new nearest-neighbor classifier with reduced computational complexity in search process. In the proposed classifier, the classes are divided into two sets: reference and non-reference sets. It reduces computational requriement by approximating the distance between the input and a class iwth the information of distances among the calsses. It calculates only the distance between the input and the reference classes. We convert a given classifier into RCC (reduced computational complexity but smal lincrease in misclassification probability of its corresponding RCC classifier. We designed RCC classifiers for the recognition of digits from the NIST database. We obtained an RCC classifier with 60% reduction in the computational complexity with the cost of 0.5% increase in misclassification probability.

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Data Classification Using the Robbins-Monro Stochastic Approximation Algorithm (로빈스-몬로 확률 근사 알고리즘을 이용한 데이터 분류)

  • Lee, Jae-Kook;Ko, Chun-Taek;Choi, Won-Ho
    • Proceedings of the KIPE Conference
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    • 2005.07a
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    • pp.624-627
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    • 2005
  • This paper presents a new data classification method using the Robbins Monro stochastic approximation algorithm k-nearest neighbor and distribution analysis. To cluster the data set, we decide the centroid of the test data set using k-nearest neighbor algorithm and the local area of data set. To decide each class of the data, the Robbins Monro stochastic approximation algorithm is applied to the decided local area of the data set. To evaluate the performance, the proposed classification method is compared to the conventional fuzzy c-mean method and k-nn algorithm. The simulation results show that the proposed method is more accurate than fuzzy c-mean method, k-nn algorithm and discriminant analysis algorithm.

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Efficient Heuristic Algorithms for Drone Package Delivery Route (드론 배달 경로를 위한 효율적인 휴리스틱 알고리즘)

  • Kelkile, Yonatan Ayalew;Seyoum, Temesgen;Kim, Jai-Hoon
    • Proceedings of the Korea Information Processing Society Conference
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    • 2016.04a
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    • pp.168-170
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    • 2016
  • Drone package delivery routing problem is realistic problem used to find efficient route of drone package delivery service. In this paper, we present an approach for solving drone routing problem for package delivery service using two different heuristics algorithms, genetic and nearest neighbor. We implement and analyze both heuristics algorithms for solving the problem efficiently with respect to cost and time. The respective experimental results show that for the range of customers 10 to 50 nearest neighbor and genetic algorithms can reduce the tour length on average by 34% and 40% respectively comparing to FIFO algorithm.

Hybrid Parallel Genetic Algorithm for Traveling Salesman Problem (순회 판매원 문제를 위한 하이브리드 병렬 유전자 알고리즘)

  • Kim, Ki-Tae;Jeo, Geon-Wook
    • Journal of the Korea Safety Management & Science
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    • v.13 no.3
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    • pp.107-114
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    • 2011
  • Traveling salesman problem is to minimize the total cost for a traveling salesman who wants to make a tour given finite number of cities along with the cost of travel between each pair them, visiting each cities exactly once before returning home. Traveling salesman problem is known to be NP-hard, and it needs a lot of computing time to get the optimal solution, so that heuristics are more frequently developed than optimal algorithms. This study suggests a hybrid parallel genetic algorithm(HPGA) for traveling salesman problem The suggested algorithm combines parallel genetic algorithm, nearest neighbor search, and 2-opt. The suggested algorithm has been tested on 7 problems in TSPLIB and compared the results of existing methods(heuristics, meta-heuristics, hybrid, and parallel). Experimental results shows that HPGA could obtain good solution in total travel distance minimization.

Guitar Tab Digit Recognition and Play using Prototype based Classification

  • Baek, Byung-Hyun;Lee, Hyun-Jong;Hwang, Doosung
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.9
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    • pp.19-25
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    • 2016
  • This paper is to recognize and play tab chords from guitar musical sheets. The musical chord area of an input image is segmented by changing the image in saturation and applying the Grabcut algorithm. Based on a template matching, our approach detects tab starting sections on a segmented musical area. The virtual block method is introduced to search blanks over chord lines and extract tab fret segments, which doesn't cause the computation loss to remove tab lines. In the experimental tests, the prototype based classification outperforms Bayesian method and the nearest neighbor rule with the whole set of training data and its performance is similar to that of the support vector machine. The experimental result shows that the prediction rate is about 99.0% and the number of selected prototypes is below 3.0%.

Dummy Stored Memory Algorithm for Hopfield Model (알고리즘 수정에 의한 홉필드 모델의 성능 개선)

  • O, Sang-Hoon;Yoon, Tae-Hoon;Kim, Jae-Chang
    • Proceedings of the KIEE Conference
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    • 1987.07a
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    • pp.41-44
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    • 1987
  • Recently Hopfield proposed a model for content-addressable memory, which has been shown to be capable of storing information in a distributed fashion and determining the nearest-neighbor. Its application is, however, inherently limited to the case that the number of l's in each stored vector is nearly the same as the number of O's in that vector. If not the case, the model has high probability of failure in finding the nearest-neighbor. In this work, a modification of the Hopfield's model, which works well irrespective of the number of l's (or O's) in each stored vector, is suggested.

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