The height of double-stranded DNA (dsDNA) is measured by lift mode AFM combined with conventional tapping mode AFM. While the tip scan height is raised step by step, the tip pressure on sample is decreased gradually. ...The height of double-stranded DNA (dsDNA) is measured by lift mode AFM combined with conventional tapping mode AFM. While the tip scan height is raised step by step, the tip pressure on sample is decreased gradually. As a result, the deformation of the DNA strands decreases, and the height of double-stranded DNA (dsDNA) molecule can be deduced by the tip lift height. The measured height of dsDNA is 1.5±0.2 nm in lift mode, but only 0.8±0.2 nm in conventional tapping mode. This demonstrates that the tip pressure is a key factor in soft sample height measurement resulting in artificating lower values via conventional tap- ping mode.展开更多
In this paper, the design of a proportional integral controller (PIC) plus fuzzy logic controller (FLC) for the negative output elementary super lift Luo converter (NOESLLC) operated in discontinuous conduction mode (...In this paper, the design of a proportional integral controller (PIC) plus fuzzy logic controller (FLC) for the negative output elementary super lift Luo converter (NOESLLC) operated in discontinuous conduction mode (DCM) is presented. In spite of the many benefits viz. the high voltage transfer gain, the high efficiency, and the reduced inductor current and the capacitor voltage ripples, it natured with non-minimum phase. This characteristic makes the control of NOESLLC cumbersome. Any attempt of direct controlling the output voltage may erupt to instability. To overcome this problem, indirect regulation of the output voltage based on the two-loop controller is devised. The savvy in the inductor current control improves the dynamic response of the output voltage. The FLC is designed for the outer (voltage) loop while the inner (current) loop is controlled by the PIC. For the developed ?19.6 V NOESLLC, the dynamic performances for different perturbations (line, load and component variations) are obtained for PIC plus FLC and compared with PIC plus PIC. The study of two cases is performed at various operating regions by developing the MATLAB/Simulink model.展开更多
文摘The height of double-stranded DNA (dsDNA) is measured by lift mode AFM combined with conventional tapping mode AFM. While the tip scan height is raised step by step, the tip pressure on sample is decreased gradually. As a result, the deformation of the DNA strands decreases, and the height of double-stranded DNA (dsDNA) molecule can be deduced by the tip lift height. The measured height of dsDNA is 1.5±0.2 nm in lift mode, but only 0.8±0.2 nm in conventional tapping mode. This demonstrates that the tip pressure is a key factor in soft sample height measurement resulting in artificating lower values via conventional tap- ping mode.
文摘In this paper, the design of a proportional integral controller (PIC) plus fuzzy logic controller (FLC) for the negative output elementary super lift Luo converter (NOESLLC) operated in discontinuous conduction mode (DCM) is presented. In spite of the many benefits viz. the high voltage transfer gain, the high efficiency, and the reduced inductor current and the capacitor voltage ripples, it natured with non-minimum phase. This characteristic makes the control of NOESLLC cumbersome. Any attempt of direct controlling the output voltage may erupt to instability. To overcome this problem, indirect regulation of the output voltage based on the two-loop controller is devised. The savvy in the inductor current control improves the dynamic response of the output voltage. The FLC is designed for the outer (voltage) loop while the inner (current) loop is controlled by the PIC. For the developed ?19.6 V NOESLLC, the dynamic performances for different perturbations (line, load and component variations) are obtained for PIC plus FLC and compared with PIC plus PIC. The study of two cases is performed at various operating regions by developing the MATLAB/Simulink model.
