• Title/Summary/Keyword: Entropy technique

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Automatic Threshold Selection and Contrast Intensification Technique for Image Enhancement (영상 향상을 위한 자동 임계점 선택 및 대비 강화 기법)

  • Lee, Geum-Boon;Cho, Beom-Joon
    • Journal of Korea Multimedia Society
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    • v.11 no.4
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    • pp.462-470
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    • 2008
  • This study applies fuzzy functions to improve image quality under the assumption that uncertainty of image information due to low contrast is based on vagueness and ambiguity of the brightness pixel values. To solve the problem of low contrast images whose brightness distribution is inclined, we use the k-means algorithm as a parameter of the fuzzy function, through which automatic critical points can be found to differentiate objects from background and contrast between bright and dark points can be improved. The fuzzy function is presented at the three main stages presented to improve image quality: fuzzification, contrast enhancement and defuzzification. To measure improved image quality, we present the fuzzy index and entropy index and in comparison with those of histogram equalization technique, it shows outstanding performance.

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Study of Dynamics of Allyl Chloride-2-Butanone Binary System Using Time Domain Reflectometry

  • Sudake, Y.S.;Kamble, S.P.;Patil, S.S.;Khirade, P.W.;Mehrotra, S.C.
    • Journal of the Korean Chemical Society
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    • v.56 no.1
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    • pp.20-27
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    • 2012
  • Complex permittivity spectra of Allyl Chloride (AC), 2-Butanone (2-BU) and their binary mixtures over the entire range of concentration were obtained using the Time Domain Reflectometry (TDR) technique in microwave frequency range at various temperatures. Static dielectric constant and relaxation time are obtained from complex permittivity spectra. Density ($\rho$) and refractive index ($n_D$) are also measured. These parameters are used to determine excess dielectric constant, excess inverse relaxation time, excess molar volume, excess molar refraction, polarity, Bruggeman factor and thermodynamic parameters viz. enthalpy of activation and entropy of activation. The values of static dielectric constant and relaxation time increases while density and refractive index decreases with the percentage of 2-Butanone in Allyl Chloride increases. Excess parameters were fitted to a Redlich-Kister equation.

An Image Retrieval Technique using Entropy and Color Features (엔트로피와 색채 특징을 이용한 영상 검색 기법)

  • Kim, Tae-Hui;Jeong, Dong-Seok
    • Journal of KIISE:Computer Systems and Theory
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    • v.26 no.3
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    • pp.282-290
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    • 1999
  • 본 논문에서는 영상 데이터베이스에서의 색인화를 위해 화소간의 엔트로피(inter-pixel entropy)측면에서 영상을 해석하여 특징을 추출하는 색인기법을 제안하였다. 엔트로피를 정량적으로 나타내기 위하여 PIM(picture information measure)에 기반한 특징을 각각의 영상들로부터 추출하여 색인으로 사용하였다. 엔트로피에 기반 하는 특징은 한 영상에 대하여 3가지를 추출하였다. 첫 번째 특징은 원 영상으로부터 직접 값들을 추출하였고 영상의 해상도와 그레이 레벨을 낮추어 가면서 얻어지는 영상들로부터 두 번째, 세번째 의 엔트로피 특징을 각각 추출하였다. 일반적으로 영상의 경우에 엔트로피가 높은 영역에 정보가 집중되는 경향이 있고 엔트로피가 낮은 영역에서는 배경 영역 등의 정보를 추출하게된다. 이러한 이유로 색채 특쟁은 엔트로피에 따라서 분리된 영역에서 추출하였다. 전역검색(global search)은 엔트로피 특징을 이용하였고 색채 특징을 이용하여 지역 검색(local search)을 시도하였다. 실험은 색채와 엔트로피로 식별이 유용한 꽃 영상을 사용하였는데 원치 않는 영상이 상위 단계에서 나타나는 빈도가 기존의 타 기법에 비해 줄어들었다.

Comparison of Objective Functions for Feed-forward Neural Network Classifiers Using Receiver Operating Characteristics Graph

  • Oh, Sang-Hoon;Wakuya, Hiroshi
    • International Journal of Contents
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    • v.10 no.1
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    • pp.23-28
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    • 2014
  • When developing a classifier using various objective functions, it is important to compare the performances of the classifiers. Although there are statistical analyses of objective functions for classifiers, simulation results can provide us with direct comparison results and in this case, a comparison criterion is considerably critical. A Receiver Operating Characteristics (ROC) graph is a simulation technique for comparing classifiers and selecting a better one based on a performance. In this paper, we adopt the ROC graph to compare classifiers trained by mean-squared error, cross-entropy error, classification figure of merit, and the n-th order extension of cross-entropy error functions. After the training of feed-forward neural networks using the CEDAR database, the ROC graphs are plotted to help us identify which objective function is better.

Maximum Entropy Algorithm and its Implementation for the Neutral Beam Profile Measurement

  • Lee, Seung-Wook;Gyuseong Cho;Cho, Yong-Sub
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.10a
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    • pp.329-334
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    • 1997
  • A tomography algorithm to maximize the entropy of image using Lagrangian multiplier technique and conjugate gradient method has been designed for the measurement of 2D spatial distribution of intense neutral beams of KSTAR NBI(Korea Superconducting Tokamak Advanced Research Neutral Beam Injector) which is now being designed. A possible detection system was assumed and a numerical simulation has been implemented to test the reconstruction quality of given beam profiles. This algorithm has the good applicability for sparse projection data and thus, can be used for the neutral beam tomography.

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Codebook Reordering Technique for Entropy Coding of VQ Indexes (VQ 인덱스의 엔트로피 부호화를 위한 코드북 재정렬 기법)

  • Hwang, Jae-Ho;Hong, Choong-Seon;Lee, Dae-Young
    • Proceedings of the Korea Information Processing Society Conference
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    • 2000.10b
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    • pp.903-906
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    • 2000
  • 웨이브렛 영역에서 벡터 양자화(vector quantization)를 수행하여 생성된 VQ 인덱스들을 엔트로피 부호화(entropy coding)하면 영상의 코딩 효율을 높일 수 있다. 본 논문에서는 벡터 양자화 이전에 VQ 인덱스들의 중복성을 높이기 위해 다중해상도 코드북의 코드 워드들을 에너지 크기 순으로 재정렬하는 기법을 제안한다. 코드 워드들의 평균과 편차를 이용한 재정렬 방법과 제안된 기법을 벡터 양자화 후 생성되는 VQ 인덱스에 DPCM/Huffman 기법을 적용하여 각각에 대한 코딩 효율을 비교한다.

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A Reexamination on the Influence of Fine-particle between Districts in Seoul from the Perspective of Information Theory (정보이론 관점에서 본 서울시 지역구간의 미세먼지 영향력 재조명)

  • Lee, Jaekoo;Lee, Taehoon;Yoon, Sungroh
    • KIISE Transactions on Computing Practices
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    • v.21 no.2
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    • pp.109-114
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    • 2015
  • This paper presents a computational model on the transfer of airborne fine particles to analyze the similarities and influences among the 25 districts in Seoul by quantifying a time series data collected from each district. The properties of each district are driven with the model of a time series of the fine particle concentrations, and the calculation of edge-based weights are carried out with the transfer entropies between all pairs of the districts. We applied a modularity-based graph clustering technique to detect the communities among the 25 districts. The result indicates the discovered clusters correspond to a high transfer-entropy group among the communities with geographical adjacency or high in-between traffic volumes. We believe that this approach can be further extended to the discovery of significant flows of other indicators causing environmental pollution.

The RNA Base Over 95% of Onju Citrus and Coffee Genes Cut & Paste Based on The BCJM Matrix with Chargaff-Shannon Entropy (BCJM 행렬 및 Chargaff 법칙과 Shannon Entropy에 의한 RNA 유전자 비율이 95%이상인 온주감귤과 귤의 유전자 조합)

  • Lee, Sung Kook;Kim, Jeong Su;Lee, Moon Ho
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.4
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    • pp.415-422
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    • 2022
  • The heterogeneous Onju citrus genes (A=20.57, C=32.71, G=30.01, U=16.71%) and coffee genes (A=20.66, C=31.76, G=30.187, U=16.71%) have the same genetic ratio of 95% or more. It is known that gene compatibility is generally not possible with this group. However, it can be grafted if the conditions of Chargaff rule and Shannon Entropy are met with gene functional-similarity of more than 95%, and it becomes a new breed of Coffrange. We calculated the world's first BCJM matrix for DNA-RNA and published it in US patents and international journals. All animals and viruses are similar to human genes. Based on this, it was announced in June in the British matrix textbook by solving the genetic characteristics of COVID-19 and the human body. In plants, it is treated with BCJM-Transposon treatment, a technique that easily changes gene location. Simulation predicted that the matrix could be successful with Cut & Paste and Transpose.

An Accuracy Assessment Scheme through Entropy Analysis in BLE-based Indoor Positioning Systems (BLE 기반 실내 측위 시스템에서 엔트로피 분석을 통한 정확도 평가 기법)

  • Pi, Kyung-Joon;Min, Hong;Han, Kyoungho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.3
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    • pp.117-123
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    • 2022
  • Unlike the satellite-based outdoor positioning system, the indoor positioning system utilizes various wireless technologies such as BLE, Wi-Fi, and UWB. BLE-based beacon technology can measure the user's location by periodically broadcasting predefined device ID and location information and using RSSI from the receiving device. Existing BLE-based indoor positioning system studies have many studies comparing the error between the user's actual location and the estimated location at a single point. In this paper, we propose a technique to evaluate the positioning accuracy according to the movement path or area by applying the entropy analysis model. In addition, simulation results show that calculated entropy results for different paths can be compared to assess which path is more accurate.

High-Speed Implementation and Efficient Memory Usage of Min-Entropy Estimation Algorithms in NIST SP 800-90B (NIST SP 800-90B의 최소 엔트로피 추정 알고리즘에 대한 고속 구현 및 효율적인 메모리 사용 기법)

  • Kim, Wontae;Yeom, Yongjin;Kang, Ju-Sung
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.28 no.1
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    • pp.25-39
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    • 2018
  • NIST(National Institute of Standards and Technology) has recently published SP 800-90B second draft which is the document for evaluating security of entropy source, a key element of a cryptographic random number generator(RNG), and provided a tool implemented on Python code. In SP 800-90B, the security evaluation of the entropy sources is a process of estimating min-entropy by several estimators. The process of estimating min-entropy is divided into IID track and non-IID track. In IID track, the entropy sources are estimated only from MCV estimator. In non-IID Track, the entropy sources are estimated from 10 estimators including MCV estimator. The running time of the NIST's tool in non-IID track is approximately 20 minutes and the memory usage is over 5.5 GB. For evaluation agencies that have to perform repeatedly evaluations on various samples, and developers or researchers who have to perform experiments in various environments, it may be inconvenient to estimate entropy using the tool and depending on the environment, it may be impossible to execute. In this paper, we propose high-speed implementations and an efficient memory usage technique for min-entropy estimation algorithm of SP 800-90B. Our major achievements are the three improved speed and efficient memory usage reduction methods which are the method applying advantages of C++ code for improving speed of MultiMCW estimator, the method effectively reducing the memory and improving speed of MultiMMC by rebuilding the data storage structure, and the method improving the speed of LZ78Y by rebuilding the data structure. The tool applied our proposed methods is 14 times faster and saves 13 times more memory usage than NIST's tool.