Considering the characteristics of the UHVAC Pilot Project in China,the importance of study on electromagnetic transient overvoltage in UHVAC projects is demonstrated in this paper.Through analysis and comparison on t...Considering the characteristics of the UHVAC Pilot Project in China,the importance of study on electromagnetic transient overvoltage in UHVAC projects is demonstrated in this paper.Through analysis and comparison on the simulation programs for electromagnetic transient overvoltages,EMTP is then recommended for the UHVAC Pilot Project in China.The element models in EMTP used in simulating power frequency overvoltage and power resonance of non-entire phase operation,etc.,are introduced.The paper also points out that extra attention will be needed when simulating power frequency sequence parameters and line corona.The research outcome provides valuable references for both oversea and domestic UHVAC projects.展开更多
Firstly,the related theories about agricultural science and technology innovation and project approval evaluation are combed and summarized. By combining application and finish books of science and technology support ...Firstly,the related theories about agricultural science and technology innovation and project approval evaluation are combed and summarized. By combining application and finish books of science and technology support plan project in agricultural field of Ministry of Science and Technology with stronger innovation,case analysis and expert interview are conducted. Evaluation indexes of agricultural science and technology project based on innovation value are proposed initially,and there are 50 initial indexes. After that,via focus group talk,qualitative research is conducted to further adjust innovative evaluation indexes,and 50 initial indexes are deleted to 41. The importance of the 41 indexes is scored by the experts,and index screening and classification are conducted by verification factor analysis in structural equation model. It not only obtains index classification but also finds action mechanism among innovation demand,innovation mode,research thinking,treatment method of difficulty,and predicted risk. The research could straighten up ideas of project review experts in agricultural field and provide reference for applicant designing project.展开更多
By rewriting the projection operator P<sub>0</sub> in wavelets in another formula,we obtain a characterization of dim J<sub>V</sub><sub>0</sub>（x）where V<sub>0</sub> i...By rewriting the projection operator P<sub>0</sub> in wavelets in another formula,we obtain a characterization of dim J<sub>V</sub><sub>0</sub>（x）where V<sub>0</sub> is a Γ-shift-invariant subspace of L<sup>2</sup>（R<sup>n</sup>）derived from a dual wavelet basis and prove that there does not exist a wavelet function ψ∈ L<sup>2</sup>（R）such that （?）has compact support and ∪<sub>k</sub>∈ZZ（supp■+4πk）=R up to a zero subset of R.展开更多
文摘Considering the characteristics of the UHVAC Pilot Project in China,the importance of study on electromagnetic transient overvoltage in UHVAC projects is demonstrated in this paper.Through analysis and comparison on the simulation programs for electromagnetic transient overvoltages,EMTP is then recommended for the UHVAC Pilot Project in China.The element models in EMTP used in simulating power frequency overvoltage and power resonance of non-entire phase operation,etc.,are introduced.The paper also points out that extra attention will be needed when simulating power frequency sequence parameters and line corona.The research outcome provides valuable references for both oversea and domestic UHVAC projects.
基金Supported by Special Item of Basic Science and Technology Work,Ministry of Science and Technology(2013IM030700)Youth Fund Project of Beijing Wuzi University in 2016(0541603716)Science Research Work Fund of Beijing Wuzi University(05416049)
文摘Firstly,the related theories about agricultural science and technology innovation and project approval evaluation are combed and summarized. By combining application and finish books of science and technology support plan project in agricultural field of Ministry of Science and Technology with stronger innovation,case analysis and expert interview are conducted. Evaluation indexes of agricultural science and technology project based on innovation value are proposed initially,and there are 50 initial indexes. After that,via focus group talk,qualitative research is conducted to further adjust innovative evaluation indexes,and 50 initial indexes are deleted to 41. The importance of the 41 indexes is scored by the experts,and index screening and classification are conducted by verification factor analysis in structural equation model. It not only obtains index classification but also finds action mechanism among innovation demand,innovation mode,research thinking,treatment method of difficulty,and predicted risk. The research could straighten up ideas of project review experts in agricultural field and provide reference for applicant designing project.
文摘By rewriting the projection operator P<sub>0</sub> in wavelets in another formula,we obtain a characterization of dim J<sub>V</sub><sub>0</sub>（x）where V<sub>0</sub> is a Γ-shift-invariant subspace of L<sup>2</sup>（R<sup>n</sup>）derived from a dual wavelet basis and prove that there does not exist a wavelet function ψ∈ L<sup>2</sup>（R）such that （?）has compact support and ∪<sub>k</sub>∈ZZ（supp■+4πk）=R up to a zero subset of R.
