A kind of triple branched continued fractions is defined by making use of Samel- son inverse and Thiele-type partial inverted di?erences [1]. In this paper, a levels-recursive algorithm is constructed and a numerical ...A kind of triple branched continued fractions is defined by making use of Samel- son inverse and Thiele-type partial inverted di?erences [1]. In this paper, a levels-recursive algorithm is constructed and a numerical example is given.展开更多
Using genomic DNA of bolting-tolerant lettuce as a template,flanking fragments of lettuce plastid rpo A gene were amplified and cloned by PCR. Targeting the sites of these two fragments,homologous recombinant fragment...Using genomic DNA of bolting-tolerant lettuce as a template,flanking fragments of lettuce plastid rpo A gene were amplified and cloned by PCR. Targeting the sites of these two fragments,homologous recombinant fragments of exogenous gene were integrated to construct lettuce plastid expression vector p Brpo AGFP,which harbored the expression cassette Prrn-gfp-aad A-Tpsb A. The results showed that the amplified flanking fragments were 1.2 and 1.1 kb in size. After sequencing,restriction digestion,ligation and transformation,lettuce plastid expression vector containing expression cassette Prrn-gfp-aad A-Tpsb A was constructed and confirmed by SDS-PAGE electrophoresis. The results of SDS-PAGE electrophoresis indicated that gfp gene was efficiently expressed under the regulation of plasmid specific promoter Prrn and terminator Tpsb A. GFP accounted for 45. 6% of total soluble proteins; inclusion bodies accounted for 47.5 % of bacterial proteins,which reached relatively high expression levels. The construction of lettuce plastid expression vector p Brpo A-GFP laid a solid foundation for establishment of subsequent lettuce plastid transformation system and genetic improvement of lettuce using various functional genes.展开更多
Based on an in-depth study of wavelet gray moment, we proposed a concept of a time-division scale level moment and gave the specific definition; ulteriorly, we discussed the factors which affected the fault diagnosis ...Based on an in-depth study of wavelet gray moment, we proposed a concept of a time-division scale level moment and gave the specific definition; ulteriorly, we discussed the factors which affected the fault diagnosis ability of a time-division scale level moment. The analysis results in the caculation of six typical fault signals show that the time-division scale level moment can be used to display the detailed information of a wavelet gray level image, extract the signal＇s characteristics effectively, and distinguish the vibration fault. Compared to the method of a wave gray moment vector, the method mentioned in this paper can provide higher calculation speed and higher capacity of fault identification, so it is more suitable for online fault diagnosis for rotating machinery.展开更多
Diode clamped multi-level inverter （DCMLI） has a wide application prospect in high-voltage and adjustable speed drive systems due to its low stress on switching devices, low harmonic output, and simple structure. Ho...Diode clamped multi-level inverter （DCMLI） has a wide application prospect in high-voltage and adjustable speed drive systems due to its low stress on switching devices, low harmonic output, and simple structure. However, the problem of complexity of selecting vectors and capacitor voltage unbalance needs to be solved when the algorithm of direct torque control （DTC） is implemented on DCMLI. In this paper, a fuzzy DTC system of an induction machine fed by a three-level neutral-point-clamped （NPC） inverter is proposed. After introducing fuzzy logic, optimal selecting switching state is realized by applying various strategies which can distinguish the grade of the errors of stator flux linkage, torque, the neutral-point potential, and the position of stator flux linkage. Consequently, the neutral-point potential unbalance, the dr/dr of output voltage and the switching loss are restrained effectively, and desirable dynamic and steady-state performances of induction machines can be obtained for the DTC scheme. A design method of the fuzzy controller is introduced in detail, and the relevant simulation and experimental results have verified the feasibility of the proposed control algorithm.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No. 10171026.
文摘A kind of triple branched continued fractions is defined by making use of Samel- son inverse and Thiele-type partial inverted di?erences [1]. In this paper, a levels-recursive algorithm is constructed and a numerical example is given.
基金Supported by Natural Science Foundation of Yunnan Province(2011FB049)National Natural Science Foundation of China(31260481,31460516)+2 种基金Fund of Yunnan Education Department(2013Y251)Fund of the Department of Life Science and Technology,Kunming University(GXKM201505)Talent Fund for PhD(YJL11015)
文摘Using genomic DNA of bolting-tolerant lettuce as a template,flanking fragments of lettuce plastid rpo A gene were amplified and cloned by PCR. Targeting the sites of these two fragments,homologous recombinant fragments of exogenous gene were integrated to construct lettuce plastid expression vector p Brpo AGFP,which harbored the expression cassette Prrn-gfp-aad A-Tpsb A. The results showed that the amplified flanking fragments were 1.2 and 1.1 kb in size. After sequencing,restriction digestion,ligation and transformation,lettuce plastid expression vector containing expression cassette Prrn-gfp-aad A-Tpsb A was constructed and confirmed by SDS-PAGE electrophoresis. The results of SDS-PAGE electrophoresis indicated that gfp gene was efficiently expressed under the regulation of plasmid specific promoter Prrn and terminator Tpsb A. GFP accounted for 45. 6% of total soluble proteins; inclusion bodies accounted for 47.5 % of bacterial proteins,which reached relatively high expression levels. The construction of lettuce plastid expression vector p Brpo A-GFP laid a solid foundation for establishment of subsequent lettuce plastid transformation system and genetic improvement of lettuce using various functional genes.
基金This paper is supported by the National Natural Science Foundation of China (NSFC) under Grant No.50775083
文摘Based on an in-depth study of wavelet gray moment, we proposed a concept of a time-division scale level moment and gave the specific definition; ulteriorly, we discussed the factors which affected the fault diagnosis ability of a time-division scale level moment. The analysis results in the caculation of six typical fault signals show that the time-division scale level moment can be used to display the detailed information of a wavelet gray level image, extract the signal＇s characteristics effectively, and distinguish the vibration fault. Compared to the method of a wave gray moment vector, the method mentioned in this paper can provide higher calculation speed and higher capacity of fault identification, so it is more suitable for online fault diagnosis for rotating machinery.
文摘Diode clamped multi-level inverter （DCMLI） has a wide application prospect in high-voltage and adjustable speed drive systems due to its low stress on switching devices, low harmonic output, and simple structure. However, the problem of complexity of selecting vectors and capacitor voltage unbalance needs to be solved when the algorithm of direct torque control （DTC） is implemented on DCMLI. In this paper, a fuzzy DTC system of an induction machine fed by a three-level neutral-point-clamped （NPC） inverter is proposed. After introducing fuzzy logic, optimal selecting switching state is realized by applying various strategies which can distinguish the grade of the errors of stator flux linkage, torque, the neutral-point potential, and the position of stator flux linkage. Consequently, the neutral-point potential unbalance, the dr/dr of output voltage and the switching loss are restrained effectively, and desirable dynamic and steady-state performances of induction machines can be obtained for the DTC scheme. A design method of the fuzzy controller is introduced in detail, and the relevant simulation and experimental results have verified the feasibility of the proposed control algorithm.
