• Title/Summary/Keyword: entropies

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Equilibria between Low-spin State ($D_{4h}$) and High-spin State ($O_h$) of the Ni(II)-$N_4$ Complex Ion ($N_4$ : 2,12-dimethyl-3,7,11,17-tetraazabicyclo-11,3,1-heptadeca-1(17),2,11,13,15-pentaene) (Ni(II)-$N_4$ 착이온의 낮은 스핀상태 ($D_{4h}$)와 높은 스핀상태 ($O_h$)간의 평형 ($N_4$ : 2,12-dimethyl-3,7,11,17-tetraazabicyclo-11,3,1-heptadeca-1(17),2,11,13,15-pentaene))

  • Yu-Chul Park;Jong-Chul Byun;Mahn-Su Yu
    • Journal of the Korean Chemical Society
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    • v.33 no.6
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    • pp.607-613
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    • 1989
  • The chemical equilibria of Ni(II)-tetraamine (tetraamine = 2,12-dimethyl-3,7,11,17-tetraazabicyclo-11,3,1-heptadeca-1(17),2,11,13,15-pentaene) complex ion in water, acetonitrile, acetone and nitromethane were investigated using spectrophotometric method, respectively. The equilibria between low-spin ($D_{4h}$) and high-spin ($O_h$) structures of Ni-tetraamine complex ion were presented in water, acetonitrile and acetone, but not in nitromethane. The eqilibrium constants, the reaction enthalpies and the reaction entropies were determined from analysis of the temperature dependence of the electronic spectra. The formation of the triplet species ($O_h$) was found to be exothermic. The solvent and electrolyte effects on the equilibrium constants could be explained by the dielectric constants of solvents and the reaction entropies.

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Energy Distribution Characteristics of Nonstationary Acoustic Emission Burst Signal Using Time-frequency Analysis (비정상 AE 진동감시 신호의 에너지 분포특성과 시간-주파수 해석)

  • Jeong, Tae-Gun
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.22 no.3
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    • pp.291-297
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    • 2012
  • Conventional Fourier analysis can give only limited information about the dynamic characteristics of nonstationary signals. Instead, time-frequency analysis is widely used to investigate the nonstationary signal in detail. Several time-frequency analysis methods are compared for a typical acoustic emission burst generated during the impact between a ferrite ceramic and aluminum plate. This AE burst is inherently nonstationary and random containing many frequency contents, which leads to severe interference between cross terms in bilinear convolution type distributions. The smoothing and reassignment processes can improve the readability and resolution of the results. Spectrogram and scalogram of the AE burst are obtained and compared to get the characteristics information. Renyi entropies are computed for various bilinear time-frequency transforms to evaluate the randomness. These bilinear transforms are reassigned by using the improved algorithm in discrete computation.

Transient State Theory of Significant Liquid Structure Applied to Nitrogen Oxides (액체 구조의 천이상태이론의 질소산화물들에 대한 적용)

  • Kim, Sang-Hyung;Pak, Hyung-Suk;Kim, Kak-Choong;Chang, Sei-Hun
    • Journal of the Korean Chemical Society
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    • v.11 no.3
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    • pp.105-110
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    • 1967
  • The transient state theory of significant liquid structure is applied to nitrous oxide and nitrogen tetroxide. The partition functions for the two liquids are derived according to the transient state theory. The various thermodynamic properties; such as, molar volumes, vapor pressures, entropies of vaporization, and critical point properties agree well with the experimental values.

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The Effect of Pressure on the Rate of Solvolysis (Ⅲ) Kinetics on the Nucleophilic Substitution Reactions of Acyl- and Alkyl groups in Binary Solvents (가용매분해반응속도에 대한 압력의 영향(Ⅲ) 이성분용매내 Acyl류와 Alkyl류의 친핵성 치환반응의 속도론적 연구)

  • Kyong, Jin Burm;Park, Byoung Chun;Kwun, Oh Cheun
    • Journal of the Korean Chemical Society
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    • v.41 no.9
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    • pp.443-448
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    • 1997
  • Kinetics for the solvolyses of acyl chlorides and alkyl chlorides in hydroxylic solvent mixtures have been measured by conductometric method at various temperatures and pressures. The activation parameters (${\Delta}V^{\neq},\; {\Delta}H^{\neq},\; {\Delta}S^{\neq}$) were estimated from the rate constants. The reactivities of these reactions were also estimated from the correlation of the activation volumes with the activation entropies.

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Implementation of Image Adaptive Map (적응적인 Saliency Map 모델 구현)

  • Park, Sang-Bum;Kim, Ki-Joong;Han, Young-Joon;Hahn, Hern-Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.25 no.2
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    • pp.131-139
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    • 2008
  • This paper presents a new saliency map which is constructed by providing dynamic weights on individual features in an input image to search ROI(Region Of Interest) or FOA(Focus Of Attention). To construct a saliency map on there is no a priori information, three feature-maps are constructed first which emphasize orientation, color, and intensity of individual pixels, respectively. From feature-maps, conspicuity maps are generated by using the It's algorithm and their information quantities are measured in terms of entropy. Final saliency map is constructed by summing the conspicuity maps weighted with their individual entropies. The prominency of the proposed algorithm has been proved by showing that the ROIs detected by the proposed algorithm in ten different images are similar with those selected by one-hundred person's naked eyes.

Rates and Mechanism of Adsorption of Transition Metal Ions on Polystyrene Resins Supported Diethylenetriamine (디에틸렌트리아민을 지지시킨 폴리스틸렌수지에 대한 전이금속이온의 흡착속도와 메카니즘)

  • Kim, Sun-Deuk;Shin, Yun-Yeol;Kim, Chang-Su
    • Analytical Science and Technology
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    • v.12 no.6
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    • pp.465-471
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    • 1999
  • Chloromethylated polystyrene resins supported diethylenetriamine of linear and claw types have been prepared by the reaction of diethylenetriamine with chloromethylated polystyrene. The kinetics of adsorption of transition metal ions on polystyrene resins were measured by the limited-bath technique. This paper reports the results of the diffusion coefficients, entropies of activation, and free energies of activation. The ratedetermining step of the adsorption of transition metals on the resins is a process of diffusion through the particles.

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TOPOLOGICAL ENTROPY OF A SEQUENCE OF MONOTONE MAPS ON CIRCLES

  • Zhu Yuhun;Zhang Jinlian;He Lianfa
    • Journal of the Korean Mathematical Society
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    • v.43 no.2
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    • pp.373-382
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    • 2006
  • In this paper, we prove that the topological entropy of a sequence of equi-continuous monotone maps $f_{1,\infty}={f_i}\;\infty\limits_{i=1}$on circles is $h(f_{1,\infty})={\frac{lim\;sup}{n{\rightarrow}\infty}}\;\frac 1 n \;log\;{\prod}\limits_{i=1}^n|deg\;f_i|$. As applications, we give the estimation of the entropies for some skew products on annular and torus. We also show that a diffeomorphism f on a smooth 2-dimensional closed manifold and its extension on the unit tangent bundle have the same entropy.

Similarity Measure Construction of the Fuzzy Set for the Reliable Data Selection (신뢰성 있는 정보의 추출을 위한 퍼지집합의 유사측도 구성)

  • Lee Sang-Hyuk
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.9C
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    • pp.854-859
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    • 2005
  • We construct the fuzzy entropy for measuring of uncertainty with the help of relation between distance measure and similarity measure. Proposed fuzzy entropy is constructed through distance measure. In this study, the distance measure is used Hamming distance measure. Also for the measure of similarity between fuzzy sets or crisp sets, we construct similarity measure through distance measure, and the proposed 려zzy entropies and similarity measures are proved.

Entropy and information energy arithmetic operations for fuzzy numbers

  • Hong, Dug-Hun;Kim, Kyung-Tae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.6
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    • pp.754-758
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    • 2005
  • There have been several tipical methods being used tomeasure the fuzziness (entropy) of fuzzy sets. Pedrycz is the original motivation of this paper. Recently, Wang and Chiu [FSS103(1999) 443-455] and Pedrycz [FSS 64(1994) 21-30] showed the relationship(addition, subtraction, multiplication) between the entropies of the resultant fuzzy number and the original fuzzy numbers of same type. In this paper, using Lebesgue-Stieltjes integral, we generalize results of Wang and Chiu [FSS 103(1999) 443-455] concerning entropy arithmetic operations without the condition of same types of fuzzy numbers. And using this results and trade-off relationship between information energy and entropy, we study more properties of information energy of fuzzy numbers.

Voice Activity Detection Based on Signal Energy and Entropy-difference in Noisy Environments (엔트로피 차와 신호의 에너지에 기반한 잡음환경에서의 음성검출)

  • Ha, Dong-Gyung;Cho, Seok-Je;Jin, Gang-Gyoo;Shin, Ok-Keun
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.5
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    • pp.768-774
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    • 2008
  • In many areas of speech signal processing such as automatic speech recognition and packet based voice communication technique, VAD (voice activity detection) plays an important role in the performance of the overall system. In this paper, we present a new feature parameter for VAD which is the product of energy of the signal and the difference of two types of entropies. For this end, we first define a Mel filter-bank based entropy and calculate its difference from the conventional entropy in frequency domain. The difference is then multiplied by the spectral energy of the signal to yield the final feature parameter which we call PEED (product of energy and entropy difference). Through experiments. we could verify that the proposed VAD parameter is more efficient than the conventional spectral entropy based parameter in various SNRs and noisy environments.