| 1 | Recognition of practical speech emotion using improved shuffled frog leaping algorithm显示文摘Due to the drawbacks in Support Vector Machine(SVM)parameter optimization,an Improved Shuffled Frog Leaping Algorithm(Im-SFLA)was proposed,and the learning ability in practical speech emotion recognition was improved.Firstly,we introduced Simulated Annealing(SA),Immune Vaccination(Iv),Gaussian mutation and chaotic disturbance into the basic SFLA,which bManced the search efficiency and population diversity effectively.Secondly,Im-SFLA Was applied to the optimization of SVM parameters,and an Im-SFLA-SVM method Was proposed.Thirdly,the acoustic features of practical speech emotion,such aS ridgetiness,were analyzed.The pitch frequency,short-term energy,formant frequency and chaotic characteristics were analyzed corresponding to different emotion categories,and we constructed a 144-dimensional emotion feature vector for recognition and reduced to 4-dimension by adopting Linear Discriminant Analysis(LDA) Finally,the Im-SFLA-SVM method Was tested on the practical speech emotion database,and the recognition results were compared with Shuffled Frog Leaping Algorithm optimization-SVM(SFLA-SVM)method,Particle Swarm Optimization algorithm optimization-SVM(PSo-SVM) method,basic SVM,Gaussian Mixture Model(GMM)method and Back Propagation(BP)neural network method.The experimentM resuits showed that the average recognition rate of Im-SFLA-SVM method was 77.8%,which had improved 1.7%,2.7%,3.4%,4.7%and 7.8%respectively,compared with the other methods.The recognition of fidgetiness was significantly improve,thus verifying that Im-SFLA was an effective SVM parameter selection method,and the Im-SFLA-SVM method may significantly improve the practical speech emotion recognition. | ZHANG Xiaodan HUANG Chengwei ZHAO Li ZOU Cairong | 2014 | Chinese Journal of Acoustics2014,33,4: | 4 |
| 3 | Vibration Frequency Characteristic Study of Two-stage Excitation Valve Used in Vibration Experiment System显示文摘To satisfy the demands of higher frequency and amplitude in hydraulic vibration experiment system,the two-stage excitation valve is presented,and a mathematical model of two-stage excitation valve is established after analyzing the working principle of two-stage excitation valve,then the influence of relevant parameters on the displacement of main spool of two-stage excitation valve is studied by using Matlab/Simulink to calculate and analyze.The results show that the displacement of main spool will be smaller with bigger diameter and more secondary valve ports.When the reversing frequency is higher and the oil supply pressure is lower as well as the axial guide width of valve ports is smaller,the maximum displacement of main spool is smaller.The new two-stage excitation valve is easy to adjust reversing frequency and flow.The high frequency can be achieved by improving the rotation speed of servo motor and adding the number of secondary valve ports;the large flow can be realized by increasing the axial guide width of secondary valve ports and oil supply pressure.The result of this study is of guiding significance for designing the rotary valve for the achievement of higher reversing frequency and larger flow. | Yongping WU Chengwei XIONG Yi LIU Jiafei ZHENG Mingxuan ZOU | 2020 | Mechanical Engineering Science2020,2,1: | 1 |