• Title/Summary/Keyword: Maximum Entropy

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The Ordered Weighted Averaging (OWA) Operator Weighting Functions with Constant Value of Orness and Application to the Multiple Criteria Decision Making Problems (순위가 있는 가중치 평균 방법에서 일정한 수준의 결합력을 갖는 가중치 함수의 성질 및 다기준의사결정 문제에의 활용)

  • Ahn, Byeong-Seok
    • Asia pacific journal of information systems
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    • v.16 no.1
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    • pp.85-101
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    • 2006
  • Actual type of aggregation performed by an ordered weighted averaging (OWA) operator heavily depends upon the weighting vector. A number of approaches have been suggested for obtaining the associated weights. In this paper, we present analytic forms of OWA operator weighting functions, each of which has such properties as rank-based weights and constant value of orness, irrespective of number of objectives aggregated. Specifically, we propose four analytic forms of OWA weighting functions that can be positioned at 0.25, 0.334, 0.667, and 0.75 on the orness scale. The merits for using these weights over other weighting schemes can be mentioned in a couple of ways. Firstiy, we can efficiently utilize the analytic forms of weighting functions without solving complicated mathematical programs once the degree of orness is specified a priori by decision maker. Secondly, combined with well-known OWA operator weights such as max, min, and average, any weighting vectors, having a desired value of orness and being independent of the number of objectives, can be generated. This can be accomplished by convex combinations of predetermined weighting functions having constant values of orness. Finally, in terms of a measure of dispersion, newly generated weighting vectors show just a few discrepancies with weights generated by maximum entropy OWA.

Implementation of a Dialogue Interface System Using Pattern Matching and Statistical Modeling (패턴 매칭과 통계 모델링을 이용한 대화 인터페이스 시스템의 구현)

  • Kim, Hark-Soo
    • The Journal of Korean Association of Computer Education
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    • v.10 no.3
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    • pp.67-73
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    • 2007
  • In this paper, we review essential constituents of a dialogue interface system and propose practical methods to implement the each constituent. The implemented system consists of a discourse manager, an intention analyzer, a named entity recognizer, a SQL query generator, and a response generator. In the progress of implementation, the intention analyzer uses a maximum entropy model based on statistics because the domain dependency of the intention analyzer is comparatively low. The others use a simple pattern matching method because they needs high domain portability. In the experiments in a schedule arrangement domain, the implemented system showed the precision of 88.1% in intention analysis and the success rate of 83,4% in SQL query generation.

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The Auto Regressive Parameter Estimation and Pattern Classification of EKS Signals for Automatic Diagnosis (심전도 신호의 자동분석을 위한 자기회귀모델 변수추정과 패턴분류)

  • 이윤선;윤형로
    • Journal of Biomedical Engineering Research
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    • v.9 no.1
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    • pp.93-100
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    • 1988
  • The Auto Regressive Parameter Estimation and Pattern Classification of EKG Signal for Automatic Diagnosis. This paper presents the results from pattern discriminant analysis of an AR (auto regressive) model parameter group, which represents the HRV (heart rate variability) that is being considered as time series data. HRV data was extracted using the correct R-point of the EKG wave that was A/D converted from the I/O port both by hardware and software functions. Data number (N) and optimal (P), which were used for analysis, were determined by using Burg's maximum entropy method and Akaike's Information Criteria test. The representative values were extracted from the distribution of the results. In turn, these values were used as the index for determining the range o( pattern discriminant analysis. By carrying out pattern discriminant analysis, the performance of clustering was checked, creating the text pattern, where the clustering was optimum. The analysis results showed first that the HRV data were considered sufficient to ensure the stationarity of the data; next, that the patern discrimimant analysis was able to discriminate even though the optimal order of each syndrome was dissimilar.

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Spatial Planning of Climate Adaptation Zone to Promote Climate Change Adaptation for Endangered Species (생물다양성 보전을 위한 기후적응지역 설정 연구 -삵의 서식지를 중심으로-)

  • Lee, Dongkun;Baek, Gyounghye;Park, Chan;Kim, Hogul
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.6
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    • pp.111-117
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    • 2011
  • This study attempts to facilitate climate change adaptation in conservation area by spatial planning of climate adaptation zone for endangered species. Spatial area is South Korea and select leopard cat (Prionailurus bengalensis) as a target species of this study. In order to specify the climate adaptation zone, firstly, Maximum entropy method (Maxent) was used to identify suitable habitat, and then core habitat was selected for leopard cat. Secondly, land use resistance index was evaluated and least cost distance was analyzed for target species. In this step we choose dispersal capacity of leopard cat to reflect species ecological characteristic. Finally, climate adaptation zone is described and adaptation measures are suggested. The presented approach could be generalized for application into conservation planning and restoration process. Furthermore, spatial planning of climate adaptation zone could increase heterogeneity of habitat and improve adaptive capacity of species and habitat itself.

Two-stage variable block-size multiresolution motion estiation in the wavelet transform domain (웨이브렛 변환영역에서의 2단계 가변 블록 다해상도 움직임 추정)

  • 김성만;이규원;정학진;박규태
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.7
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    • pp.1487-1504
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    • 1997
  • In this paper, the two-stage variable block-size multiresolution motion algorithm is proposed for an interframe coding scheme in the wavelet decomposition. An optimal bit allocagion between motion vectors and the prediction error in sense of minimizing the total bit rate is obtained by the proposed algorithm. The proposed algorithm consists of two stages for motion estimatation and only the first stage can be separated and run on its own. The first stage of the algorithm introduces a new method to give the lower bit rate of the displaced frame difference as well as a smooth motion field. In the second stage of the algorithm, the technique is introduced to have more accurate motion vectors in detailed areas, and to decrease the number of motion vectors in uniform areas. The algorithm aims at minimizin gthe total bit rate which is sum of the motion vectors and the displaced frame difference. The optimal bit allocation between motion vectors and displaced frame difference is accomplished by reducing the number of motion vectors in uniform areas and it is based on a botom-up construction of a quadtree. An entropy criterion aims at the control of merge operation. Simulation resuls show that the algorithm lends itself to the wavelet based image sequence coding and outperforms the conventional scheme by up to the maximum 0.28 bpp.

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Optimization of Reflectron for Kinetic and Mechanistic Studies with Multiplexed Multiple Tandem (MSn) Time-of-flight Mass Spectrometry

  • Bae, Yong-Jin;Yoon, So-Hee;Moon, Jeong-Hee;Kim, Myung-Soo
    • Bulletin of the Korean Chemical Society
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    • v.31 no.1
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    • pp.92-99
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    • 2010
  • Photoexcitation of a precursor ion inside a cell floated at high voltage installed in a tandem time-of-flight (TOF) mass spectrometer provides triple tandem mass spectrometric information and allows kinetic and mechanistic studies. In this work, the factors affecting, or downgrading, the performance of the technique were identified. Ion-optical and computational analyses showed that an optimum instrument could be designed by utilizing a reflectron with linear-plus-quadratic potential inside. Theoretical predictions were confirmed by tests with instruments built with different ion-optical layout. With optimized instruments, masses of intermediate ions in the consecutive dissociation of a precursor ion could be determined with the maximum error of $\pm5$ Da. We also observed excellent agreement in dynamical parameters (critical energy and entropy) for the dissociation of a model peptide ion determined by instruments with different ion-optical layout operated under optimum conditions. This suggests that these parameters can be determined reliably by the kinetic method developed previously when properly designed and operated tandem TOF instruments are used.

Dielectric Properties Dependent on Cross-1inking Agent in Silicone Rubber (실리콘고무의 가교제 변화에 의한 유전특성)

  • Kwon, B.H.;Lee, S.I.;Hong, J.W.;Lee, J.U.;Lee, W.J.
    • Elastomers and Composites
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    • v.22 no.1
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    • pp.20-28
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    • 1987
  • The characteristic of the dielectric relaxation in silicone rubbers were studied in the frequency range of $1{\times}10^2{\sim}3{\times}10^6Hz$ at the temperature range of $30^{\circ}{\sim}170^{\circ}C$. As the results of the study, it has been confirmed that the silicone rubber containing the cross-linking agants of 2,5-bis(tert-butylperoxy)-2, 5-dimethyl hexane exhibit the dissipation spectra of two kind(${\alpha},\;{\beta}$ dissipation) due to the siloxane and methyl groups. Particularly, the maximum value of dielectric loss spectra of silicone rubber combinning the cross-linking agents of 0.7phr to 1.0phr are on the increasing in high frequency region, but the specimen of above 1.0phr become smaller again. The energy and the entropy of activation on the molicular motion obtained 18.32 kcal/mole and $1.48ca1/mole{\cdot}deg$ in measuring condition respectively.

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Identification of Chinese Event Types Based on Local Feature Selection and Explicit Positive & Negative Feature Combination

  • Tan, Hongye;Zhao, Tiejun;Wang, Haochang;Hong, Wan-Pyo
    • Journal of information and communication convergence engineering
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    • v.5 no.3
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    • pp.233-238
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    • 2007
  • An approach to identify Chinese event types is proposed in this paper which combines a good feature selection policy and a Maximum Entropy (ME) model. The approach not only effectively alleviates the problem that classifier performs poorly on the small and difficult types, but improve overall performance. Experiments on the ACE2005 corpus show that performance is satisfying with the 83.5% macro - average F measure. The main characters and ideas of the approach are: (1) Optimal feature set is built for each type according to local feature selection, which fully ensures the performance of each type. (2) Positive and negative features are explicitly discriminated and combined by using one - sided metrics, which makes use of both features' advantages. (3) Wrapper methods are used to search new features and evaluate the various feature subsets to obtain the optimal feature subset.

How Do Liquid Crystal Molecules Align on Treated Surfaces?

  • Okada, Yoshinori;Shioda, Tatsutoshi;Chung, Doo-Han;Park, Byoung-Choo;Takezoe, Hideo
    • Journal of Information Display
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    • v.4 no.2
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    • pp.29-34
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    • 2003
  • We have studied liquid crystal (LC) molecular alignment on rubbed and photoaligned surfaces. Particular attention was paid to the intermolecular liquid crystalline interaction. We will first show that uniform molecular orientation on a rubbed surface does not mean spatially uniform interaction between the surface and LC molecules. Rather LCs tend to align themselves through LC interaction. The existence of nonuniformity of rubbing was successfully visualized by double surface treatment. The importance of intermolecular LC interaction was also found in the orientation formation process in 5CB evaporated on rubbed and photoaligned surfaces. By simultaneously analyzing polarized UVNIS absorption and second-harmonic generation (SHG) using the maximum entropy method, we succeeded in obtaining the temporal variation of the orientational distribution functions in the film forming process. The distribution anisotropy and pretilt are found to be generated under the influence of intermolecular LC interaction.

Statistical Analysis and Prediction for Behaviors of Tracked Vehicle Traveling on Soft Soil Using Response Surface Methodology (반응표면법에 의한 연약지반 차량 거동의 통계적 분석 및 예측)

  • Lee Tae-Hee;Jung Jae-Jun;Hong Sup;Km Hyung-Woo;Choi Jong-Su
    • Journal of Ocean Engineering and Technology
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    • v.20 no.3 s.70
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    • pp.54-60
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    • 2006
  • For optimal design of a deep-sea ocean mining collector system, based on self-propelled mining vehicle, it is imperative to develop and validate the dynamic model of a tracked vehicle traveling on soft deep seabed. The purpose of this paper is to evaluate the fidelity of the dynamic simulation model by means of response surface methodology. Various statistical techniques related to response surface methodology, such as outlier analysis, detection of interaction effect, analysis of variance, inference of the significance of design variables, and global sensitivity analysis, are examined. To obtain a plausible response surface model, maximum entropy sampling is adopted. From statistical analysis and prediction for dynamic responses of the tracked vehicle, conclusions will be drawn about the accuracy of the dynamic model and the performance of the response surface model.