For the structural-acoustic radiation optimization problem under external loading,acoustic radiation power was considered to be an objective function in the optimization method. The finite element method(FEM) and boun...For the structural-acoustic radiation optimization problem under external loading,acoustic radiation power was considered to be an objective function in the optimization method. The finite element method(FEM) and boundary element method(BEM) were adopted in numerical calculations,and structural response and the acoustic response were assumed to be de-coupled in the analysis. A genetic algorithm was used as the strategy in optimization. In order to build the relational expression of the pressure objective function and the power objective function,the enveloping surface model was used to evaluate pressure in the acoustic domain. By taking the stiffened panel structural-acoustic optimization problem as an example,the acoustic power and field pressure after optimized was compared. Optimization results prove that this method is reasonable and effective.展开更多
The hexagonal BaNd x Fe12?x O19(x=0.1?1.0) fine powders with M-type structure were synthesized by sol-gel auto-combustion high-temperature synthesis method. The structure of powders, gels’ combustion and magnetic pro...The hexagonal BaNd x Fe12?x O19(x=0.1?1.0) fine powders with M-type structure were synthesized by sol-gel auto-combustion high-temperature synthesis method. The structure of powders, gels’ combustion and magnetic properties of powders were respectively studied by means of X-ray diffractometer (XRD), differential thermal analysis-thermogravimetric analysis (DTA-TG) and vibrating sample magnetometer (VSM). The powders before and after combustion and calcination at 450–850 °C with different mole ratio of Nd to Ba (0.1–1.0) were compared in terms of XRD. In addition, the effects of different synthesis conditions on magnetic properties of powders were also discussed. The results show that at pH 7.0 or so, mole ratio of citrate to nitrate (1–3) and calcination temperature of 850 °C for 1 h, M-type BaNd x Fe12?x O19(x=0.1?1.0) fine powders can be obtained, and the coercive force reaches 436880 A·m?1 at x=1, which is far greater than that of barium permanent ferrite (BaFe12O19).展开更多
The paper based on the proposed integrative approach to studying music cultures of the Eastern Europe. Come to light the factors of integration promoting interference and enrichment of national musical cultures. The r...The paper based on the proposed integrative approach to studying music cultures of the Eastern Europe. Come to light the factors of integration promoting interference and enrichment of national musical cultures. The region of national composer schools actively joined in world art process in the second half of the 19th century （Czechia, Poland, and Hungary） and in the 20th century （Bulgaria, Slovakia, Romania, Serbia, Slovenia, and Macedonia） Theme of this paper is to identify the basic principles of this region. The purpose of the work, defining features of the musical cultures of the Eastern European region as a whole, also here highlights the commonality of the creative ideas of representatives of the region--Bartok, Janachek, Martinu, etc.. Method of developing is defined by their orientation to the disclosure of topic. The paper used the comparative-typological and integrated approaches and methods of analysis展开更多
This paper proposes a new method for extracting ENF （electric network frequency） fluctuations from digital audio recordings for the purpose of forensic authentication. It is shown that the extraction of ENF componen...This paper proposes a new method for extracting ENF （electric network frequency） fluctuations from digital audio recordings for the purpose of forensic authentication. It is shown that the extraction of ENF components from audio recordings is realizable by applying a parametric approach based on an AR （autoregressive） model. The proposed method is compared to the existing STFT （short-time Fourier transform） based ENF extraction method. Experimental results from recorded electrical grid signals and recorded audio signals show that the proposed approach can improve the time resolution in the extracted ENF fluctuations and improve the detection of tampering with short alterations in longer audio recordings.展开更多
Folk music in the past was inherited through family tradition, apprenticeship, social folk life, etc., mainly by the way of oral teaching method. Since the founding of New China, the country in addition to investigate...Folk music in the past was inherited through family tradition, apprenticeship, social folk life, etc., mainly by the way of oral teaching method. Since the founding of New China, the country in addition to investigate and research the minority musicians, takes into consideration the special education and minority musical heritage and the establishment of different forms and characteristics of art institutions. In the inheritance and development of folk music, the advantages of school education cannot be ignored. We should pay attention to the inheritance and development of folk music in college music reform, so that music education has become a platform to promote the national music culture.展开更多
文摘For the structural-acoustic radiation optimization problem under external loading,acoustic radiation power was considered to be an objective function in the optimization method. The finite element method(FEM) and boundary element method(BEM) were adopted in numerical calculations,and structural response and the acoustic response were assumed to be de-coupled in the analysis. A genetic algorithm was used as the strategy in optimization. In order to build the relational expression of the pressure objective function and the power objective function,the enveloping surface model was used to evaluate pressure in the acoustic domain. By taking the stiffened panel structural-acoustic optimization problem as an example,the acoustic power and field pressure after optimized was compared. Optimization results prove that this method is reasonable and effective.
文摘The hexagonal BaNd x Fe12?x O19(x=0.1?1.0) fine powders with M-type structure were synthesized by sol-gel auto-combustion high-temperature synthesis method. The structure of powders, gels’ combustion and magnetic properties of powders were respectively studied by means of X-ray diffractometer (XRD), differential thermal analysis-thermogravimetric analysis (DTA-TG) and vibrating sample magnetometer (VSM). The powders before and after combustion and calcination at 450–850 °C with different mole ratio of Nd to Ba (0.1–1.0) were compared in terms of XRD. In addition, the effects of different synthesis conditions on magnetic properties of powders were also discussed. The results show that at pH 7.0 or so, mole ratio of citrate to nitrate (1–3) and calcination temperature of 850 °C for 1 h, M-type BaNd x Fe12?x O19(x=0.1?1.0) fine powders can be obtained, and the coercive force reaches 436880 A·m?1 at x=1, which is far greater than that of barium permanent ferrite (BaFe12O19).
文摘The paper based on the proposed integrative approach to studying music cultures of the Eastern Europe. Come to light the factors of integration promoting interference and enrichment of national musical cultures. The region of national composer schools actively joined in world art process in the second half of the 19th century （Czechia, Poland, and Hungary） and in the 20th century （Bulgaria, Slovakia, Romania, Serbia, Slovenia, and Macedonia） Theme of this paper is to identify the basic principles of this region. The purpose of the work, defining features of the musical cultures of the Eastern European region as a whole, also here highlights the commonality of the creative ideas of representatives of the region--Bartok, Janachek, Martinu, etc.. Method of developing is defined by their orientation to the disclosure of topic. The paper used the comparative-typological and integrated approaches and methods of analysis
文摘This paper proposes a new method for extracting ENF （electric network frequency） fluctuations from digital audio recordings for the purpose of forensic authentication. It is shown that the extraction of ENF components from audio recordings is realizable by applying a parametric approach based on an AR （autoregressive） model. The proposed method is compared to the existing STFT （short-time Fourier transform） based ENF extraction method. Experimental results from recorded electrical grid signals and recorded audio signals show that the proposed approach can improve the time resolution in the extracted ENF fluctuations and improve the detection of tampering with short alterations in longer audio recordings.
文摘Folk music in the past was inherited through family tradition, apprenticeship, social folk life, etc., mainly by the way of oral teaching method. Since the founding of New China, the country in addition to investigate and research the minority musicians, takes into consideration the special education and minority musical heritage and the establishment of different forms and characteristics of art institutions. In the inheritance and development of folk music, the advantages of school education cannot be ignored. We should pay attention to the inheritance and development of folk music in college music reform, so that music education has become a platform to promote the national music culture.
