Different from the previous qualitative analysis of linear systems in time and frequency domains, the method for describing nonlinear systems quantitatively is proposed based on correlated dimensions. Nonlinear dynami...Different from the previous qualitative analysis of linear systems in time and frequency domains, the method for describing nonlinear systems quantitatively is proposed based on correlated dimensions. Nonlinear dynamics theory is used to analyze the pressure data of a contrarotating axial flow fan. The delay time is 18 and the embedded dimension varies from 1 to 25 through phase-space reconstruction. In addition, the correlated dimensions are calculated before and after stalling. The results show that the correlated dimensions drop from 1. 428 before stalling to 1. 198 after stalling, so they are sensitive to the stalling signal of the fan and can be used as a characteristic quantity for the judging of the fan stalling.展开更多
The molecular characterization of the weighted atomic Hardy space Hw p,q,s is given. As an application, the boundedness of Hilbert transform on the weighted Hardy space is proved.
With respect to the practice, now popular in the mass media, of substituting a few scholars＇ individual text readings for widespread reading by the general public, a practice spearheaded by the CCTV program ＂Lecture...With respect to the practice, now popular in the mass media, of substituting a few scholars＇ individual text readings for widespread reading by the general public, a practice spearheaded by the CCTV program ＂Lecture Room,＂ we have in this essay come up with the term ＂second-hand reading of the classics＂ as a core concept characterizing this phenomenon. The cultural deficiencies symbolized by such ＂second-hand reading＂ t＇md their expression in three phenomena： first, the audience, eager to become culturally enlightened, find themselves in the passive role of mere receivers of scholars＇ interpretations of the classics, lacking the role of autonomous readers. Second, the media, motivated by commercial aims, opt for an inappropriate cultural strategy and over-reach their proper role. Third, scholars, taking their orientation from the powerful mass media and following the commercial logic that ＂the audience is king,＂ settle for a misplaced role and degenerate from being ＂guides to the best in culture＂ into merely catering to mass taste. To redress such a situation, our strategy should be to coordinate the universities, public libraries, the media and other public resources in a concerted effort to switch from ＂second-hand reading＂ led by the media to self-initiated ＂autonomous reading,＂ so as to rebuild a public intellectual sphere.展开更多
基金Supported by the Natural Science Foundation of Jiangsu Province(BK2005018)the Graduate Research and Innovation Plan of Jiangsu Province(CX07B-061Z)~~
文摘Different from the previous qualitative analysis of linear systems in time and frequency domains, the method for describing nonlinear systems quantitatively is proposed based on correlated dimensions. Nonlinear dynamics theory is used to analyze the pressure data of a contrarotating axial flow fan. The delay time is 18 and the embedded dimension varies from 1 to 25 through phase-space reconstruction. In addition, the correlated dimensions are calculated before and after stalling. The results show that the correlated dimensions drop from 1. 428 before stalling to 1. 198 after stalling, so they are sensitive to the stalling signal of the fan and can be used as a characteristic quantity for the judging of the fan stalling.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 19631080, 69735020)
文摘The molecular characterization of the weighted atomic Hardy space Hw p,q,s is given. As an application, the boundedness of Hilbert transform on the weighted Hardy space is proved.
文摘With respect to the practice, now popular in the mass media, of substituting a few scholars＇ individual text readings for widespread reading by the general public, a practice spearheaded by the CCTV program ＂Lecture Room,＂ we have in this essay come up with the term ＂second-hand reading of the classics＂ as a core concept characterizing this phenomenon. The cultural deficiencies symbolized by such ＂second-hand reading＂ t＇md their expression in three phenomena： first, the audience, eager to become culturally enlightened, find themselves in the passive role of mere receivers of scholars＇ interpretations of the classics, lacking the role of autonomous readers. Second, the media, motivated by commercial aims, opt for an inappropriate cultural strategy and over-reach their proper role. Third, scholars, taking their orientation from the powerful mass media and following the commercial logic that ＂the audience is king,＂ settle for a misplaced role and degenerate from being ＂guides to the best in culture＂ into merely catering to mass taste. To redress such a situation, our strategy should be to coordinate the universities, public libraries, the media and other public resources in a concerted effort to switch from ＂second-hand reading＂ led by the media to self-initiated ＂autonomous reading,＂ so as to rebuild a public intellectual sphere.
