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THE NEW MODEL FOR CALCULATION OF STANDARD ENTROPIES OF SOLID COMPOUNDS Ⅲ CALCULATION FOR STANDARD ENTROPIES OF SOLID BINARY OXIDES
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作者 Xun Min YU Yuan Li ZHAO Dao Wu YANG (Jingzhou Educalional College Hubei. 414100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期405-406,共2页
This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 ... This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 binary oxides. and found good agreemenl between estimated and experimental entropies. 展开更多
关键词 CALCULATION FOR STANDARD entropies OF SOLID BINARY OXIDES THE NEW MODEL FOR CALCULATION OF STANDARD entropies OF SOLID COMPOUNDS
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IONIC ENTROPIES ON A BOND PARAMETER SCALE
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作者 周振华 《天津工业大学学报》 CAS 北大核心 1990年第2期34-37,共4页
Some expressions were proposed in the previous report to exp-ress the relation between the entropies S°<sub>298</sub> and the bond parameterZ/r in the same type of compounds.Based on this we derived a... Some expressions were proposed in the previous report to exp-ress the relation between the entropies S°<sub>298</sub> and the bond parameterZ/r in the same type of compounds.Based on this we derived a rela-tion formula for calculating the ionic entropies and established a 展开更多
关键词 BOND PARAMETERS IONIC entropies
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Fisher and Shannon information entropies for a noncentral inversely quadratic plus exponential Mie-type potential
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作者 Ituen B Okon Cecilia N Isonguyo +2 位作者 Akaninyene D Antia Akpan N Ikot Oyebola O Popoola 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第6期43-56,共14页
In this work,we determine the Fisher and Shannon entropies,the expectation values and the squeeze state for a noncentral inversely quadratic plus exponential Mie-type potential analytically.The proposed potential is s... In this work,we determine the Fisher and Shannon entropies,the expectation values and the squeeze state for a noncentral inversely quadratic plus exponential Mie-type potential analytically.The proposed potential is solved under the Schr?dinger equation using a special Greene Aldrich approximation to the centrifugal term to obtain a normalised wave function within the framework of the Nikiforov–Uvarov method.Numerical results are obtained for different screening parameters:α?=?0.1,0.12 and 0.13 for varying real constant parameter(B).The numerical solutions are obtained only for ground state.The numerical results of Fisher entropy both for position and momentum spaces are in good agreement with existing literature.The normalisation constant,wave function,and probability density plots are carried out using a well designed Mathematica algorithm.The Fourier transform of position space entropy gives the momentum space entropy. 展开更多
关键词 Fisher and Shannon entropies Schr?dinger equation expectation values Nikiforov–Uvarov method
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Shannon information entropies for rectangular multiple quantum well systems with constant total lengths
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作者 M Solaimani Guo-Hua Sun Shi-Hai Dong 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第4期154-163,共10页
We first study the Shannon information entropies of constant total length multiple quantum well systems and then explore the effects of the number of wells and confining potential depth on position and momentum inform... We first study the Shannon information entropies of constant total length multiple quantum well systems and then explore the effects of the number of wells and confining potential depth on position and momentum information entropy density as well as the corresponding Shannon entropy.We find that for small full width at half maximum(FWHM) of the position entropy density,the FWHM of the momentum entropy density is large and vice versa.By increasing the confined potential depth,the FWHM of the position entropy density decreases while the FWHM of the momentum entropy density increases.By increasing the potential depth,the frequency of the position entropy density oscillation within the quantum barrier decreases while that of the position entropy density oscillation within the quantum well increases.By increasing the number of wells,the frequency of the position entropy density oscillation decreases inside the barriers while it increases inside the quantum well.As an example,we might localize the ground state as well as the position entropy densities of the1 st,2 nd,and 6 th excited states for a four-well quantum system.Also,we verify the Bialynicki–Birula–Mycieslki(BBM)inequality. 展开更多
关键词 position and momentum Shannon entropies multiple quantum well entropy densities
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THE ENTROPIES OF THE COLLAPSING STAR AND OF THE BLACK HOLE
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《Research in Astronomy and Astrophysics》 SCIE CAS 1982年第2期104-106,共3页
We put forth three modes of black hole formation, i.e. (1) A black hole kern forms initially inside the collapsing star. (2) The different mass shells of the collapsing star fulfils the Schwarzschild condition simulta... We put forth three modes of black hole formation, i.e. (1) A black hole kern forms initially inside the collapsing star. (2) The different mass shells of the collapsing star fulfils the Schwarzschild condition simultaneously. (3) Only the outmost mass shell of the collapsing star fulfils the Schwarzschild condition. We then calculate the entropy of the collapsing star for modes (1) and (3) and find that they are only 10-19 times the entropy of black hole. Modes (1) may be occure during the supernova explosions or galaxy explosions. Mode (3) may be occur in the formation of galactic black hole. 展开更多
关键词 MODE THE entropies OF THE COLLAPSING STAR AND OF THE BLACK HOLE STAR
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Analytical Fitting Functions of Finite Sample Discrete Entropies of White Gaussian Noise 被引量:5
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作者 杨正瓴 冯勇 +2 位作者 熊定方 陈曦 张军 《Transactions of Tianjin University》 EI CAS 2015年第4期299-303,共5页
In order to find the convergence rate of finite sample discrete entropies of a white Gaussian noise(WGN), Brown entropy algorithm is numerically tested.With the increase of sample size, the curves of these finite samp... In order to find the convergence rate of finite sample discrete entropies of a white Gaussian noise(WGN), Brown entropy algorithm is numerically tested.With the increase of sample size, the curves of these finite sample discrete entropies are asymptotically close to their theoretical values.The confidence intervals of the sample Brown entropy are narrower than those of the sample discrete entropy calculated from its differential entropy, which is valid only in the case of a small sample size of WGN. The differences between sample Brown entropies and their theoretical values are fitted by two rational functions exactly, and the revised Brown entropies are more efficient. The application to the prediction of wind speed indicates that the variances of resampled time series increase almost exponentially with the increase of resampling period. 展开更多
关键词 ENTROPY NON-STATIONARY time series prediction WHITE GAUSSIAN noise SAMPLE size wind speed
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Quantum information entropies of the eigenstates for the Pschl-Teller-like potential 被引量:2
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作者 Guo-Hua Sun M. Avila Aoki Shi-Hai Dong 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期113-117,共5页
Shannon entropy for lower position and momentum eigenstates of Ptschl-Teller-like potential is evaluated. Based on the entropy densities demonstrated graphically, we note that the wave through of the position informat... Shannon entropy for lower position and momentum eigenstates of Ptschl-Teller-like potential is evaluated. Based on the entropy densities demonstrated graphically, we note that the wave through of the position information entropy density p (x) moves right when the potential parameter V1 increases and its amplitude decreases. However, its wave through moves left with the increase in the potential parameter 丨V2丨. Concerning the momentum information entropy density p(p), we observe that its amplitude increases with increasing potential parameter V1, but its amplitude decreases with increasing丨V2丨. The Bialynicki-Birula-Mycielski (BBM) inequality has also been tested for a number of states. Moreover, there exist eigenstates that exhibit squeezing in the momentum information entropy. Finally, we note that position information entropy increases with V1, but decreases with 丨V2丨, However, the variation of momentum information entropy is contrary to that of the position information entropy. 展开更多
关键词 bound states quantum information entropy Poschl-Teller-like potential
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Complexity analysis and dynamic characteristics of EEG using MODWT based entropies for identification of seizure onset 被引量:1
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作者 Shivarudhrappa Raghu Natarajan Sriraam +3 位作者 Yasin Temel Shyam Vasudeva Rao Alangar Sathyaranjan Hegde Pieter L Kubben 《The Journal of Biomedical Research》 CAS CSCD 2020年第3期213-227,共15页
In this paper,complexity analysis and dynamic characteristics of electroencephalogram(EEG) signal based on maximal overlap discrete wavelet transform(MODWT) has been exploited for the identification of seizure onset.S... In this paper,complexity analysis and dynamic characteristics of electroencephalogram(EEG) signal based on maximal overlap discrete wavelet transform(MODWT) has been exploited for the identification of seizure onset.Since wavelet-based studies were well suited for classification of normal and epileptic seizure EEG,we have applied MODWT which is an improved version of discrete wavelet transform(DWT).The selection of optimal wavelet sub-band and features plays a crucial role to understand the brain dynamics in epileptic patients.Therefore,we have investigated MODWT using four different wavelets,namely Haar,Coif4,Dmey,and Sym4 sub-bands until seven levels.Further,we have explored the potentials of six entropies,namely sigmoid,Shannon,wavelet,Renyi,Tsallis,and Steins unbiased risk estimator(SURE) entropies in each sub-band.The sigmoid entropy extracted from Haar wavelet in sub-band D4 showed the highest accuracy of 98.44% using support vector machine classifier for the EEG collected from Ramaiah Medical College and Hospitals(RMCH).Further,the highest accuracy of 100% and 94.51% was achieved for the University of Bonn(UBonn) and CHB-MIT databases respectively.The findings of the study showed that Haar and Dmey wavelets were found to be computationally economical and expensive respectively.Besides,in terms of dynamic characteristics,MODWT results revealed that the highest energy present in sub-bands D2,D3,and D4 and entropies in those respective sub-bands outperformed other entropies in terms of classification results for RMCH database.Similarly,using all the entropies,sub-bands D5 and D6 outperformed other sub-bands for UBonn and CHB-MIT databases respectively.In conclusion,the comparison results of MODWT outperformed DWT. 展开更多
关键词 ELECTROENCEPHALOGRAM epileptic seizures ENTROPY maximal overlap discrete wavelet transform sigmoid entropy support vector machine
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Generalized Conditional Entropies of Partitions on Quantum Logic 被引量:1
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作者 Alexey E. Rastegin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第12期819-822,共4页
For partitions on quantum logic, the Rdnyi and Tsallis conditional entropies are introduced. Several relations between the conditional entropies of such partitions are derived.
关键词 quantum logic Renyi entropy Tsallis entropy
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Uncertainty and Certainty Relations for Pauli Observables in Terms of R′enyi Entropies of Order α ∈(0;1] 被引量:1
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作者 Alexey E.Rastegin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第3期293-298,共6页
We obtain uncertainty and certainty relations of state-independent form for the three Paufi observables with use of the Renyi entropies of order α∈ (0; 1]. It is shown that these entropic bounds are tight in the s... We obtain uncertainty and certainty relations of state-independent form for the three Paufi observables with use of the Renyi entropies of order α∈ (0; 1]. It is shown that these entropic bounds are tight in the sense that they are always reached with certain pure states. A new result is the condition for equality in Renyi-entropy uncertainty relations for the Pauli observables. Upper entropic bounds in the pure-state case are also novel. Combining the presented bounds leads to a band, in which the rescaled average Renyi a-entropy ranges for a pure measured state. A width of this band is compared with the Tsallis formulation derived previously. 展开更多
关键词 Pauli observables Renyi entropy quantum measurement uncertainty principle
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Dynamics of Information Entropies of Atom-Field Entangled States Generated via the Jaynes-Cummings Model
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作者 R.Pakniat M.K.Tavassoly M.H.Zandi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第3期266-272,共7页
In this paper we have studied the dynamical evolution of Shannon information entropies in position and momentum spaces for two classes of(nonstationary) atom-field entangled states,which are obtained via the JaynesC... In this paper we have studied the dynamical evolution of Shannon information entropies in position and momentum spaces for two classes of(nonstationary) atom-field entangled states,which are obtained via the JaynesCummings model and its generalization.We have focused on the interaction between two- and(1)-type three-level atoms with the single-mode quantized field.The three-dimensional plots of entropy densities in position and momentum spaces are presented versus corresponding coordinates and time,numerically.It is observed that for particular values of the parameters of the systems,the entropy squeezing in position space occurs.Finally,we have shown that the well-known BBM(Beckner,Bialynicki-Birola and Mycielsky) inequality,which is a stronger statement of the Heisenberg uncertainty relation,is properly satisfied. 展开更多
关键词 Shannon information entropy entropy squeezing BBM inequality Jaynes-Cummings model
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Practical Method of Estimating Standard Entropies of Cations in Solid Compounds
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作者 冯长君 《International Journal of Mining Science and Technology》 SCIE EI 1999年第1期103-106,共4页
The standard entropy Sm of the cation in solid compound is represented by using the greatest principal quantum number (n) and electron number (m) of the highest energy level group in ground state atom. There is a high... The standard entropy Sm of the cation in solid compound is represented by using the greatest principal quantum number (n) and electron number (m) of the highest energy level group in ground state atom. There is a high correlativity between Sm and n, m, with the coefficient of multiple correlation being 0. 993. The binary linear regres siou equation Sm = 8. 58+ 8. 03n+ 0. 33m is built up by the least square method, and proved highly effective by the F test under the significance level a= 0. 01. The correlativity between Sm and m increases with the increase of n. 展开更多
关键词 STANDARD CATION ENTROPY principal quantum number correlation analysis
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Uncertainty and Certainty Relations for Successive Projective Measurements of a Qubit in Terms of Tsallis' Entropies
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作者 Alexey E.Rastegin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第6期687-694,共8页
We study uncertainty and certainty relations for two successive measurements of two-dimensional observables. Uncertainties in successive measurement are considered within the following two scenarios. In the first scen... We study uncertainty and certainty relations for two successive measurements of two-dimensional observables. Uncertainties in successive measurement are considered within the following two scenarios. In the first scenario, the second measurement is performed on the quantum state generated affer the first measurement with completely erased information. In the second scenario, the second measurement is performed on the post-first- tioned on the actual measurement outcome. Induced entropies. For two successive projective t state condiquantum uncertainties are characterized by means of the Tsallis t of a qubit, we obtain minimal and maximal values of related entropic measures of induced uncertainties. Some conclusions found in the second scenario are extended to arbitrary finite dimensionality. In particular, a connection with mutual unbiasedness is emphasized. 展开更多
关键词 successive measurements Tsallis entropy uncertainty principle PURITY
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Thermodynamical and Statistical-Mechanical Entropies of the General Static Spherically Symmetric Black Hole
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作者 JING Ji-liang 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第4期240-242,共3页
The thermodynamical entropy of the general four-dimensional static spherically symmetric black hole is obtained by using the Euclidean path integral approach of Gibbons-Hawking,and its statistical-mechanical entropy i... The thermodynamical entropy of the general four-dimensional static spherically symmetric black hole is obtained by using the Euclidean path integral approach of Gibbons-Hawking,and its statistical-mechanical entropy is calculated according to the brick wall model of’t Hooft.It is shown that the two entropies are not identical in general and the difference between them depends on the area of the horizon and the Ricci scalar curvature on the event horizon. 展开更多
关键词 ENTROPY CURVATURE RICCI
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Entropies of the Y-Junction Type Nanostructures
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作者 Ricai Luo Aisha Javed +3 位作者 Muhammad Azeem Muhammad Kamran Jamil Hassan Raza Muhammad Yasir Ilyas 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2665-2679,共15页
Recent research on nanostructures has demonstrated their importance and application in a variety of fields.Nanostructures are used directly or indirectly in drug delivery systems,medicine and pharmaceuticals,biologica... Recent research on nanostructures has demonstrated their importance and application in a variety of fields.Nanostructures are used directly or indirectly in drug delivery systems,medicine and pharmaceuticals,biological sensors,photodetectors,transistors,optical and electronic devices,and so on.The discovery of carbon nanotubes with Y-shaped junctions is motivated by the development of future advanced electronic devices.Because of their interactionwithY-junctions,electronic switches,amplifiers,and three-terminal transistors are of particular interest.Entropy is a concept that determines the uncertainty of a system or network.Entropy concepts are also used in biology,chemistry,and applied mathematics.Based on the requirements,entropy in the form of a graph can be classified into several types.In 1955,graph-based entropy was introduced.One of the types of entropy is edgeweighted entropy.We examined the abstract form of Y-shaped junctions in this study.Some edge-weight-based entropy formulas for the generic view of Y-shaped junctions were created,and some edge-weighted and topological index-based concepts for Y-shaped junctions were discussed in the present paper. 展开更多
关键词 Y-shaped junctions three-terminal junctions nanostuctures entropy carbon nanotube
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Shannon information entropies for position-dependent mass Schrdinger problem with a hyperbolic well
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作者 Sun Guo-Hua Duan Popov +1 位作者 Oscar Camacho-Nieto Dong Shi-Hai 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期45-52,共8页
The Shannon information entropy for the Schrodinger equation with a nonuniform solitonic mass is evaluated for a hyperbolic-type potential. The number of nodes of the wave functions in the transformed space z are brok... The Shannon information entropy for the Schrodinger equation with a nonuniform solitonic mass is evaluated for a hyperbolic-type potential. The number of nodes of the wave functions in the transformed space z are broken when recovered to original space x. The position Sx and momentum S p information entropies for six low-lying states are calculated. We notice that the Sx decreases with the increasing mass barrier width a and becomes negative beyond a particular width a,while the Sp first increases with a and then decreases with it. The negative Sx exists for the probability densities that are highly localized. We find that the probability density ρ(x) for n = 1, 3, 5 are greater than 1 at position x = 0. Some interesting features of the information entropy densities ρs(x) and ρs(p) are demonstrated. The Bialynicki-Birula-Mycielski(BBM)inequality is also tested for these states and found to hold. 展开更多
关键词 position-dependent mass Shannon information entropy hyperbolic potential Fourier transform
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Standard-state entropies and their impact on the potential-dependent apparent activation energy in electrocatalysis
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作者 Kai S.Exner 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期247-254,I0008,共9页
The apparent activation energy,Eapp,is a common measure in thermal catalysis to discuss the activity and limiting steps of catalytic processes on solid-state materials.Recently,the electrocatalysis community adopted t... The apparent activation energy,Eapp,is a common measure in thermal catalysis to discuss the activity and limiting steps of catalytic processes on solid-state materials.Recently,the electrocatalysis community adopted the concept of Eappand combined it with the Butler-Volmer theory.Certain observations though,such as potential-dependent fluctuations of Eapp,are yet surprising because they conflict with the proposed linear decrease in Eappwith increasing overpotential.The most common explanation for this finding refers to coverage changes upon alterations in the temperature or the applied electrode potential.In the present contribution,it is demonstrated that the modulation of surface coverages cannot entirely explain potential-dependent oscillations of Eapp,and rather the impact of entropic contributions of the transition states has been overlooked so far.In the case of a nearly constant surface coverage,these entropic contributions can be extracted by a dedicated combination of Tafel plots and temperature-dependent experiments. 展开更多
关键词 ELECTROCATALYSIS Standard-state entropy Microkinetic modeling Apparent activation energy Degree of rate control
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A New Model for Calculation of Standard Entropies of Solid Compounds Ⅳ-Calculation of Standard Entropies of Solid Complex Silicates S
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作者 Xun Min YU(Department of Chemistry, Jingzhou Teachers College, Hubei 434100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第5期477-479,共3页
This paper presents a new model for the calculation of the standard entropies of solidcomplex silicates as follows.4. =53.63+9914-72.81 J/kmol (R=0.9915, Sd=5.39)Sixty complex silicates have been investigated, and go... This paper presents a new model for the calculation of the standard entropies of solidcomplex silicates as follows.4. =53.63+9914-72.81 J/kmol (R=0.9915, Sd=5.39)Sixty complex silicates have been investigated, and good agreement was found between theestimated and experimental entropy values. 展开更多
关键词 standard entropy silicate pseudo-positiveion
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Analysis of entropies based on empirical mode decomposition in amnesic mild cognitive impairment of diabetes mellitus
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作者 Dong Cui Jinhuan Wang +3 位作者 Zhijie Bian Qiuli Li Lei Wang Xiaoli Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2015年第5期11-30,共20页
EEG characteristics that correlate with the cognitive functions are important in detecting mild cognitive impairment(MCI)in T2DM.To investigate the complexity between aMCI group and age-matched non-aMCI control group ... EEG characteristics that correlate with the cognitive functions are important in detecting mild cognitive impairment(MCI)in T2DM.To investigate the complexity between aMCI group and age-matched non-aMCI control group in T2DM,six entropies combining empirical mode decomposition(EMD),including Approximate entropy(ApEn),Sample entropy(SaEn),Fuzzy entropy(FEn),Permutation entropy(PEn),Power spectrum entropy(PsEn)and Wavelet entropy(WEn)were used in the study.A feature extraction technique based on maximization of the area under the curve(AUC)and a support vector machine(SVM)were subsequently used to for features selection and classi¯cation.Finally,Pearson's linear correlation was employed to study associations between these entropies and cognitive functions.Compared to other entropies,FEn had a higher classification accuracy,sensitivity and specificity of 68%,67.1% and 71.9%,respectively.Top 43 salient features achieved classification accuracy,sensitivity and speci¯city of 73.8%,72.3% and 77.9%,respectively.P4,T4 and C4 were the highest ranking salient electrodes.Correlation analysis showed that FEn based on EMD was positively correlated to memory at electrodes F7,F8 and P4,and PsEn based on EMD was positively correlated to Montreal cognitive assessment(MoCA)and memory at electrode T4.In sum,FEn based on EMD in righttemporal and occipital regions may be more suitable for early diagnosis of the MCI with T2DM. 展开更多
关键词 ENTROPY empirical mode decomposition amnestic mild cognitive impairment type 2 diabetes mellitus
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Quantum entropies of electromagnetic and gravitational fields on Taub-NUT black hole background
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作者 刘晓莹 《Journal of Chongqing University》 CAS 2005年第4期243-246,共4页
The main characteristics and Petrov type of Taub-NUT spacetime are studied, and the quantum entropy of Taub-NUT black hole due to electromagnetic and gravitational fields is calculated via brick-wall model. It is show... The main characteristics and Petrov type of Taub-NUT spacetime are studied, and the quantum entropy of Taub-NUT black hole due to electromagnetic and gravitational fields is calculated via brick-wall model. It is shown that the quantum entropy has both the linearly and the logarithmically divergent terms. For electromagnetic field, these terms depend on the characteristic of the black hole; while for gravitational field, they depend not only on the characteristic of the black hole but also on the spin of the fields. 展开更多
关键词 Taub-NUT black hole electromagnetic field gravitational field quantum entropy
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