• Title/Summary/Keyword: Entropy-based Model

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Modeling the Spatial Distribution of Black-Necked Cranes in Ladakh Using Maximum Entropy

  • Meenakshi Chauhan;Randeep Singh;Puneet Pandey
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.4 no.2
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    • pp.79-85
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    • 2023
  • The Tibetan Plateau is home to the only alpine crane species, the black-necked crane (Grus nigricollis). Conservation efforts are severely hampered by a lack of knowledge on the spatial distribution and breeding habitats of this species. The ecological niche modeling framework used to predict the spatial distribution of this species, based on the maximum entropy and occurrence record data, allowed us to generate a species-specific spatial distribution map in Ladakh, Trans-Himalaya, India. The model was created by assimilating species occurrence data from 486 geographical sites with 24 topographic and bioclimatic variables. Fourteen variables helped forecast the distribution of black-necked cranes by 96.2%. The area under the curve score for the model training data was high (0.98), indicating the accuracy and predictive performance of the model. Of the total study area, the areas with high and moderate habitat suitability for black-necked cranes were anticipated to be 8,156 km2 and 6,759 km2, respectively. The area with high habitat suitability within the protected areas was 5,335 km2. The spatial distribution predicted using our model showed that the majority of speculated conservation areas bordered the existing protected areas of the Changthang Wildlife Sanctuary. Hence, we believe, that by increasing the current study area, we can account for these gaps in conservation areas, more effectively.

Overfitting Reduction of Intelligence Web Search based on Enforcement Learning (강화학습에 기초한 지능형 웹 검색의 과잉적합 감소방안)

  • Han, Song-Yi;Jung, Yong-Gyu
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.3
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    • pp.25-30
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    • 2009
  • Recent days intellectual systems using reinforcement learning are being researched at various fields of game and web searching applications. A good training models are called to be fitted with trainning data and also classified with new records accurately. A overfitted model with training data may possibly bring the unfavored fallacy of hasty generalization. But it would be unavoidable in actual world. The entropy and mutation model are suggested to reduce the overfitting problems on this paper. It explains variation of entropy and artificial development of entropy in datamining, which can tell development of mutation to survive in nature world. Periodical generation of maximum entropy are introduced in this paper to reduce overfitting. Maximum entropy model can be considered as a periodical generalization in intensified process of intellectual web searching.

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Feature Subset Selection Algorithm based on Entropy (엔트로피를 기반으로 한 특징 집합 선택 알고리즘)

  • 홍석미;안종일;정태충
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.41 no.2
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    • pp.87-94
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    • 2004
  • The feature subset selection is used as a preprocessing step of a teaming algorithm. If collected data are irrelevant or redundant information, we can improve the performance of learning by removing these data before creating of the learning model. The feature subset selection can also reduce the search space and the storage requirement. This paper proposed a new feature subset selection algorithm that is using the heuristic function based on entropy to evaluate the performance of the abstracted feature subset and feature selection. The ACS algorithm was used as a search method. We could decrease a size of learning model and unnecessary calculating time by reducing the dimension of the feature that was used for learning.

교통망 평형리론을 응용한 결합 모형의 개발

  • 전경수
    • Journal of Korean Society of Transportation
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    • v.7 no.2
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    • pp.45-52
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    • 1989
  • The network equilibrium theory is to estimate the travel choices on a transportation network when the resulting travel times and costs are one basis for the choices. Increasing use of this principle on travel assignment problem lead to develop the combined choice models including not only travel options such as mode and route, but location options like trip distribution problems. This paper, first, reviews earlier developments of variable demand network equilibrium models, combined modeles of trip distribution and assignment, and entropy constrained combined models. Then various model structures of combining travel choice models based on network equilibrium theory and entropy constraints are discussed.

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Which country's end devices are most sharing vulnerabilities in East Asia? (거시적인 관점에서 바라본 취약점 공유 정도를 측정하는 방법에 대한 연구)

  • Kim, Kwangwon;Won, Yoon Ji
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.25 no.5
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    • pp.1281-1291
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    • 2015
  • Compared to the past, people can control end devices via open channel. Although this open channel provides convenience to users, it frequently turns into a security hole. In this paper, we propose a new human-centered security risk analysis method that puts weight on the relationship between end devices. The measure derives from the concept of entropy rate, which is known as the uncertainty per a node in a network. As there are some limitations to use entropy rate as a measure in comparing different size of networks, we divide the entropy rate of a network by the maximum entropy rate of the network. Also, we show how to avoid the violation of irreducible, which is a precondition of the entropy rate of a random walk on a graph.

Performance Comparison of Feature Parameters and Classifiers for Speech/Music Discrimination (음성/음악 판별을 위한 특징 파라미터와 분류기의 성능비교)

  • Kim Hyung Soon;Kim Su Mi
    • MALSORI
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    • no.46
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    • pp.37-50
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    • 2003
  • In this paper, we evaluate and compare the performance of speech/music discrimination based on various feature parameters and classifiers. As for feature parameters, we consider High Zero Crossing Rate Ratio (HZCRR), Low Short Time Energy Ratio (LSTER), Spectral Flux (SF), Line Spectral Pair (LSP) distance, entropy and dynamism. We also examine three classifiers: k Nearest Neighbor (k-NN), Gaussian Mixure Model (GMM), and Hidden Markov Model (HMM). According to our experiments, LSP distance and phoneme-recognizer-based feature set (entropy and dunamism) show good performance, while performance differences due to different classifiers are not significant. When all the six feature parameters are employed, average speech/music discrimination accuracy up to 96.6% is achieved.

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A cross-entropy algorithm based on Quasi-Monte Carlo estimation and its application in hull form optimization

  • Liu, Xin;Zhang, Heng;Liu, Qiang;Dong, Suzhen;Xiao, Changshi
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.13 no.1
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    • pp.115-125
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    • 2021
  • Simulation-based hull form optimization is a typical HEB (high-dimensional, expensive computationally, black-box) problem. Conventional optimization algorithms easily fall into the "curse of dimensionality" when dealing with HEB problems. A recently proposed Cross-Entropy (CE) optimization algorithm is an advanced stochastic optimization algorithm based on a probability model, which has the potential to deal with high-dimensional optimization problems. Currently, the CE algorithm is still in the theoretical research stage and rarely applied to actual engineering optimization. One reason is that the Monte Carlo (MC) method is used to estimate the high-dimensional integrals in parameter update, leading to a large sample size. This paper proposes an improved CE algorithm based on quasi-Monte Carlo (QMC) estimation using high-dimensional truncated Sobol subsequence, referred to as the QMC-CE algorithm. The optimization performance of the proposed algorithm is better than that of the original CE algorithm. With a set of identical control parameters, the tests on six standard test functions and a hull form optimization problem show that the proposed algorithm not only has faster convergence but can also apply to complex simulation optimization problems.

Information Theoretic Approach to Middle Korean [ß] (정보이론 기반 중세국어 'ㅸ'의 음운론적 대립에 대한 연구)

  • Park, Sunwoo
    • Korean Linguistics
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    • v.79
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    • pp.63-89
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    • 2018
  • This study explores contrastive relation among voiced bilabial fricative [${\ss}$], voiceless bilabial stop [p] and glide [w] in Middle Korean consonant system based on Probabilistic Model. Preceding researches about voiced bilabial fricative [${\ss}$] proposed two influential arguments. One is voiced bilabial fricative [${\ss}$] was an independent phoneme, the other is it was not an independent phoneme but an allophone of voiceless bilabial stop [p] in Middle Korean. This study applies Probabilistic Phonological Relationship Model (PPRM) for solving the problem of dichotomy about contrastive and allophonic relations. The analysis result of the contrastive entropy by PPRM suggests that voiced bilabial fricative [${\ss}$] was just an allophone of voiceless bilabial stop [p] or glide [w] in Middle Korean. Comparing the entropies between [p] and other consonants with the entropies between [${\ss}$] and other consonants, a continuum defined in terms of entropy reveals that [${\ss}$] in Middle Korean was more allophonic than phonemic.

An Anomalous Event Detection System based on Information Theory (엔트로피 기반의 이상징후 탐지 시스템)

  • Han, Chan-Kyu;Choi, Hyoung-Kee
    • Journal of KIISE:Information Networking
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    • v.36 no.3
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    • pp.173-183
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    • 2009
  • We present a real-time monitoring system for detecting anomalous network events using the entropy. The entropy accounts for the effects of disorder in the system. When an abnormal factor arises to agitate the current system the entropy must show an abrupt change. In this paper we deliberately model the Internet to measure the entropy. Packets flowing between these two networks may incur to sustain the current value. In the proposed system we keep track of the value of entropy in time to pinpoint the sudden changes in the value. The time-series data of entropy are transformed into the two-dimensional domains to help visually inspect the activities on the network. We examine the system using network traffic traces containing notorious worms and DoS attacks on the testbed. Furthermore, we compare our proposed system of time series forecasting method, such as EWMA, holt-winters, and PCA in terms of sensitive. The result suggests that our approach be able to detect anomalies with the fairly high accuracy. Our contributions are two folds: (1) highly sensitive detection of anomalies and (2) visualization of network activities to alert anomalies.

On Information Theoretic Index for Measuring the Stochastic Dependence Among Sets of Variates

  • Kim, Hea-Jung
    • Journal of the Korean Statistical Society
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    • v.26 no.1
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    • pp.131-146
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    • 1997
  • In this paper the problem of measuring the stochastic dependence among sets fo random variates is considered, and attention is specifically directed to forming a single well-defined measure of the dependence among sets of normal variates. A new information theoretic measure of the dependence called dependence index (DI) is introduced and its several properties are studied. The development of DI is based on the generalization and normalization of the mutual information introduced by Kullback(1968). For data analysis, minimum cross entropy estimator of DI is suggested, and its asymptotic distribution is obtained for testing the existence of the dependence. Monte Carlo simulations demonstrate the performance of the estimator, and show that is is useful not only for evaluation of the dependence, but also for independent model testing.

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