• Title/Summary/Keyword: distance measure method

Search Result 743, Processing Time 0.028 seconds

Estimation of Classification Error Based on the Bhattacharyya Distance for Data with Multimodal Distribution (Multimodal 분포 데이터를 위한 Bhattacharyya distance 기반 분류 에러예측 기법)

  • 최의선;이철희
    • Proceedings of the IEEK Conference
    • /
    • 2000.06d
    • /
    • pp.85-87
    • /
    • 2000
  • In pattern classification, the Bhattacharyya distance has been used as a class separability measure and provides useful information for feature selection and extraction. In this paper, we propose a method to predict the classification error for multimodal data based on the Bhattacharyya distance. In our approach, we first approximate the pdf of multimodal distribution with a Gaussian mixture model and find the bhattacharyya distance and classification error. Exprimental results showed that there is a strong relationship between the Bhattacharyya distance and the classification error for multimodal data.

  • PDF

Character Matching Using a Hausdorff Distance (Hausdorff 거리를 이용한 문자 매칭)

  • Kim, Kyeongtaek;Kyung, Ji Hun
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.38 no.2
    • /
    • pp.56-62
    • /
    • 2015
  • The Hausdorff distance is commonly used as a similarity measure between two-dimensional binary images. Since the document images may be contaminated by a variety of noise sources during transmission, scanning or conversion to digital form, the measure should be robust to the noise. Original Hausdorff distance has been known to be sensitive to outliers. Transforming the given image to grayscale image is one of methods to deal with the noises. In this paper, we propose a Hausdorff distance applied to grayscale images. The proposed method is tested with synthetic images with various levels of noises and compared with other methods to show its robustness.

A Study on Distance Measurement using CSS and RSSI in WPAN (개인 무선네트워크에서 CSS 방식과 RSSI 를 이용한 거리측정에 관한 연구)

  • Kwon, Tai-Gil;Cho, Jin-Woong;Lim, Seung-Ok;Lee, Jang-Yeon;Lee, Hyeon-Seok;Won, Yun-Jae
    • Proceedings of the IEEK Conference
    • /
    • 2008.06a
    • /
    • pp.321-322
    • /
    • 2008
  • CSS(Chirp Spread Spectrum) technology adopt SDS-TWR algorithms of TOA(Time of Arrival) using velocity of specific medium and ToF(Time of Flight) to measure a distance, but this method always has a regular error on distance regardless of a real distance, as a result, in far distance, it decrease a error on distance relatively, but in near distance, it increase a error on distance relatively. in this paper, we propose and test new method measuring a distance more precisely in near distance using CSS and RSSI

  • PDF

Parallelism Measurement of Rolls by Using a Laser Interferometer (레이저 간섭계를 이용한 롤 평행도 측정 기술)

  • Choi, Jong Geun;Kim, Seongeun
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.23 no.6
    • /
    • pp.642-646
    • /
    • 2014
  • This research describes the measurement of roll parallelism by a laser interferometer. Parallelism among rolls is an important factor for improving the precision of printing devices. A laser interferometer, which is a device for the precise measurement of distance, can be utilized to measure parallelisms between rolls. To measure distance between two rolls by using a laser interferometer, the laser must not be severed during measurement. To achieve this condition, a linear motion guide was installed to each roll being measured, and continuous measurement of distance between two rolls was implemented by the simultaneous control of two mirrors installed on the guides. The method to measure parallelism between two rolls presented in this research can be utilized to improve printing precision by enhancing parallelism between rolls in printing devices.

Video-based Walking Distance Measurement for the Visually Impaired (시각 장애인을 위한 비디오 기반 보행거리 측정)

  • Park, Su-Woo;Song, Byung-Seop;Do, Yong-Tae
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.15 no.2
    • /
    • pp.139-147
    • /
    • 2009
  • When the visually impaired walks inside a building like corridor, a GPS cannot be useful for the walker in estimating his or her position unlike the case of outdoor space. This paper presents two novel methods to measure the walking distance using a low cost camera worn on the chest of the visually impaired. In the first method we analyze the periodic variation of image focusing values. Walking steps are counted by checking the period for the rough measure of the walking distance. The second method counts the step number by monitoring fixtures on the ceiling, which have a certain interval. Lamps on the ceiling appeared on the video are monitored in this paper. The T-S fuzzy theory is used to detect lamps, and the walking steps are estimated by the positional variation of the lamp due to the gait of the walker. The two methods are tested in real experiment, and the results are compared.

A New Distance Measure for a Variable-Sized Acoustic Model Based on MDL Technique

  • Cho, Hoon-Young;Kim, Sang-Hun
    • ETRI Journal
    • /
    • v.32 no.5
    • /
    • pp.795-800
    • /
    • 2010
  • Embedding a large vocabulary speech recognition system in mobile devices requires a reduced acoustic model obtained by eliminating redundant model parameters. In conventional optimization methods based on the minimum description length (MDL) criterion, a binary Gaussian tree is built at each state of a hidden Markov model by iteratively finding and merging similar mixture components. An optimal subset of the tree nodes is then selected to generate a downsized acoustic model. To obtain a better binary Gaussian tree by improving the process of finding the most similar Gaussian components, this paper proposes a new distance measure that exploits the difference in likelihood values for cases before and after two components are combined. The mixture weight of Gaussian components is also introduced in the component merging step. Experimental results show that the proposed method outperforms MDL-based optimization using either a Kullback-Leibler (KL) divergence or weighted KL divergence measure. The proposed method could also reduce the acoustic model size by 50% with less than a 1.5% increase in error rate compared to a baseline system.

Carnegie Hubble Program II : Overview and Research Status

  • Yang, Soung-Chul
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.40 no.1
    • /
    • pp.46.4-47
    • /
    • 2015
  • Carnegie Hubble Program II (hereafter CHP II) is a large Hubble Space Telescope (HST) observing campaign in the cycle 22 composed of a total of 184 orbits (132 primes + 52 parallels), which aims to measure H0 directly with an unprecedented accuracy. Unlike our previous efforts in CHP I which used Cepheids as a yardstick, CHP II takes the Population II (Pop II) distance indicators such as RR Lyraes and tip of the red giant branch stars (TRGBs) to set up a new calibration to Type Ia supernovae (SN Ia) distance. The Pop II distance scales have two immediate advantages over the classical Cepheid method: 1) The period-luminosity relation of the RR Lyrae has a scatter that is a factor of 2 smaller; 2) The RR Lyrae/TRGB distance scale can be applied to both elliptical and spiral galaxies. This will provide a great systematic benefit by ultimately allowing us to double the number of SN Ia distances based on geometry. By taking advantage of this Pop II route, we expect to measure H0 value to 3 % of error which will be the highest accuracy H0 measurement to date using the "Distance Ladder" method. In this talk I will present a brief background/overview on the CHP II, observations/data acquisition status, and ongoing research progress/preliminary results.

  • PDF

Similarity Search in Time Series Databases based on the Normalized Distance (정규 거리에 기반한 시계열 데이터베이스의 유사 검색 기법)

  • 이상준;이석호
    • Journal of KIISE:Databases
    • /
    • v.31 no.1
    • /
    • pp.23-29
    • /
    • 2004
  • In this paper, we propose a search method for time sequences which supports the normalized distance as a similarity measure. In many applications where the shape of the time sequence is a major consideration, the normalized distance is a more suitable similarity measure than the simple Lp distance. To support normalized distance queries, most of the previous work has the preprocessing step for vertical shifting which normalizes each sequence by its mean. The proposed method is motivated by the property of sequence for feature extraction. That is, the variation between two adjacent elements of a time sequence is invariant under vertical shifting. The extracted feature is indexed by the spatial access method such as R-tree. The proposed method can match time series of similar shape without vertical shifting and guarantees no false dismissals. The experiments are performed on real data(stock price movement) to verify the performance of the proposed method.

SLP Application and Validation for the Layout of User Interface Components (사용자 인터페이스 구성요소의 레이아웃을 위한 SLP 적용 및 검증)

  • Shin, Hyun-Bong;Jung, Kwang-Tae
    • IE interfaces
    • /
    • v.18 no.4
    • /
    • pp.485-493
    • /
    • 2005
  • In this study, a method that can objectively and systematically design the layout of user interface components was developed. In order to explain its application method, the method was applied to the layout design of facsimile. In particular, in order to validate the suitability of the method, comparison tests were performed for the case of facsimile. Computer simulators for layout design were made using Micromedia Flash and comparison evaluation for an existing layout and a new layout was performed in three aspects. The first comparison method was to measure and compare its movement distance when carrying out a task in two layout models. The second one was to measure and compare users' performance. The last one was to measure and compare users' subjective satisfaction after using two models. As the result, new layout design was better than the existing design in all comparison tests. The movement distance of the new layout design model was shorter than the existing model. And, its performance including task completion time and error frequency was better and users' satisfaction was higher than the existing. In conclusion, the method that was developed in this study can be very effectively used in the layout design of user interface components.

Fuzzy Technique-based Identification of Close and Distant Clusters in Clustering

  • Lee, Kyung-Mi;Lee, Keon-Myung
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.11 no.3
    • /
    • pp.165-170
    • /
    • 2011
  • Due to advances in hardware performance, user-friendly interfaces are becoming one of the major concerns in information systems. Linguistic conversation is a very natural way of human communications. Fuzzy techniques have been employed to liaison the discrepancy between the qualitative linguistic terms and quantitative computerized data. This paper deals with linguistic queries using clustering results on data sets, which are intended to retrieve the close clusters or distant clusters from the clustering results. In order to support such queries, a fuzzy technique-based method is proposed. The method introduces distance membership functions, namely, close and distant membership functions which transform the metric distance between two objects into the degree of closeness or farness, respectively. In order to measure the degree of closeness or farness between two clusters, both cluster closeness measure and cluster farness measure which incorporate distance membership function and cluster memberships are considered. For the flexibility of clustering, fuzzy clusters are assumed to be formed. This allows us to linguistically query close or distant clusters by constructing fuzzy relation based on the measures.