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A Novel Method for Prediction of Protein Domain Using Distance-Based Maximal Entropy
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作者 Shu-xue Zou Yan-xin Huang Yan Wang Chun-guang Zhou 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第3期215-223,共9页
Detecting the boundaries of protein domains is an important and challenging task in both experimental and computational structural biology. In this paper, a promising method for detecting the domain structure of a pro... Detecting the boundaries of protein domains is an important and challenging task in both experimental and computational structural biology. In this paper, a promising method for detecting the domain structure of a protein from sequence information alone is presented. The method is based on analyzing multiple sequence alignments derived from a database search. Multiple measures are defined to quantify the domain information content of each position along the sequence. Then they are combined into a single predictor using support vector machine. What is more important, the domain detection is first taken as an imbal- anced data learning problem. A novel undersampling method is proposed on distance-based maximal entropy in the feature space of Support Vector Machine (SVM). The overall precision is about 80%. Simulation results demonstrate that the method can help not only in predicting the complete 3D structure of a protein but also in the machine learning system on general im- balanced datasets. 展开更多
关键词 protein domain boundary SVM imbalanced data learning distance-based maximal entropy
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Oxidative reforming of methane for hydrogen and synthesis gas production:Thermodynamic equilibrium analysis 被引量:2
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作者 Antonio C.D.Freitas Reginaldo Guirardello 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第5期571-580,共10页
A thermodynamic analysis of methane oxidative reforming was carried out by Gibbs energy minimization (at constant pressure and temperature) and entropy maximization (at constant pressure and enthalpy) methods,to d... A thermodynamic analysis of methane oxidative reforming was carried out by Gibbs energy minimization (at constant pressure and temperature) and entropy maximization (at constant pressure and enthalpy) methods,to determine the equilibrium compositions and equilibrium temperatures,respectively.Both cases were treated as optimization problems (non-linear programming formulation).The GAMS 23.1 software and the CONOPT2 solver were used in the resolution of the proposed problems.The hydrogen and syngas production were favored at high temperatures and low pressures,and thus the oxygen to methane molar ratio (O 2 /CH 4) was the dominant factor to control the composition of the product formed.For O 2 /CH 4 molar ratios higher than 0.5,the oxidative reforming of methane presented autothermal behavior in the case of either utilizing O 2 or air as oxidant agent,but oxidation reaction with air possessed the advantage of avoiding peak temperatures in the system,due to change in the heat capacity of the system caused by the addition of nitrogen.The calculated results were compared with previously published experimental and simulated data with a good agreement between them. 展开更多
关键词 thermodynamic analysis methane oxidative reforming Gibbs energy minimization entropy maximization hydrogen and syngas production
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Stronger Version Sensitivity, Almost Finite to One Extension and Maximal Pattern Entropy 被引量:1
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作者 Yong Zou 《Communications in Mathematics and Statistics》 SCIE 2017年第2期123-139,共17页
In this paper,we introduce thickr-sensitivity,multi-r-sensitivity and block thick r-sensitivity for r≥2.We first give a characterization of a minimal system which is block thickly r-sensitive.Then we obtain a suffici... In this paper,we introduce thickr-sensitivity,multi-r-sensitivity and block thick r-sensitivity for r≥2.We first give a characterization of a minimal system which is block thickly r-sensitive.Then we obtain a sufficient condition of a minimal system which is thickly r-sensitive.The maximal pattern entropy of a multi-r-sensitive topological dynamical system is also discussed. 展开更多
关键词 Sensitivity Minimal system Almost finite to one extension Maximal type entropy
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Measurable n-sensitivity and maximal pattern entropy
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作者 Ruifeng ZHANG 《Frontiers of Mathematics in China》 SCIE CSCD 2022年第6期1169-1180,共12页
We introduce the notion of measurable n-sensitivity for measure preserving systems,and study the relation between measurable n-sensitivity and the maximal pattern entropy.We prove that,if(X,ℬ,μ,T)is ergodic,then(X,ℬ,... We introduce the notion of measurable n-sensitivity for measure preserving systems,and study the relation between measurable n-sensitivity and the maximal pattern entropy.We prove that,if(X,ℬ,μ,T)is ergodic,then(X,ℬ,μ,T)is measurable n-sensitive but not measurable(n+1)-sensitive if and only if h_(μ)^(*)(T)=log n,where h_(μ)^(*)(T)is the maximal pattern entropy of T. 展开更多
关键词 Measurable n-sensitive sequence entropy maximal pattern entropy
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Hurricane eye morphology extraction from SAR images by texture analysis 被引量:3
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作者 Weicheng NI Ad STOFFELEN Kaijun REN 《Frontiers of Earth Science》 SCIE CSCD 2022年第1期190-205,共16页
Tropical hurricanes are among the most devastating hazards on Earth.Knowledge about its intense inner-core structure and dynamics will improve hurricane forecasts and advisories.The precise morphological parameters ex... Tropical hurricanes are among the most devastating hazards on Earth.Knowledge about its intense inner-core structure and dynamics will improve hurricane forecasts and advisories.The precise morphological parameters extracted from high-resolution spaceborne Synthetic Aperture Radar(SAR)images,can play an essential role in further exploring and monitoring hurricane dynamics,especially when hurricanes undergo amplification,shearing,eyewall replacements and so forth.Moreover,these parameters can help to build guidelines for wind calibration of the more abundant,but lower resolution scatterometer wind data,thus better linking scatterometer wind fields to hurricane categories.In this paper,we develop a new method for automatically extracting the hurricane eyes from C-band SAR data by constructing Gray Level-Gradient Co-occurrence Matrices(GLGCMs).The hurricane eyewall is determined with a two-dimensional vector,generated by maximizing the class entropy of the hurricane eye region in GLGCM.The results indicate that when the hurricane is weak,or the eyewall is not closed,the hurricane eye extracted with this automatic method still agrees with what is observed visually,and it preserves the texture characteristics of the original image.As compared to Du’s wavelet analysis method and other morphological analysis methods,the approach developed here has reduced artefacts due to factors like hurricane size and has lower programming complexity.In summary,the proposed method provides a new and elegant choice for hurricane eye morphology extraction. 展开更多
关键词 hurricane eyewall morphological parameter texture analysis Gray Level-Gradient Co-occurrence Matrix Two-dimensional entropy maximization
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Trivial and Simple Spectrum for SL(d,R) Cocycles with Free Base and Fiber Dynamics
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作者 Mrio BESSA Paulo VARANDAS 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2015年第7期1113-1122,共10页
Let ACD(M, SL(d,R)) denote the pairs (f, A) so that f∈ A C Diff^1(M) is a C^1-Anosov transitive diffeomorphisms and A is an SL(d,R) cocycle dominated with respect to f. We prove that open and densely in ACD... Let ACD(M, SL(d,R)) denote the pairs (f, A) so that f∈ A C Diff^1(M) is a C^1-Anosov transitive diffeomorphisms and A is an SL(d,R) cocycle dominated with respect to f. We prove that open and densely in ACD(M, SL(d,R)), in appropriate topologies, the pair (f,A) has simple spectrum with respect to the unique maximal entropy measure μf. Then, we prove prevalence of trivial spectrum near the dynamical cocycle of an area-preserving map and also for generic cocycles in AUtLeb(M) × LP(M, SL(d, R)). 展开更多
关键词 Linear cocycles Lyapunov exponents Anosov diffeomorphisms topological conjugacy maximal entropy measures
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