A gated viewing laser radar has an excellent performance in underwater low light level imaging, and it also provides a viable solution to inhibit backscattering. In this paper, a gated viewing imaging system according...A gated viewing laser radar has an excellent performance in underwater low light level imaging, and it also provides a viable solution to inhibit backscattering. In this paper, a gated viewing imaging system according to the demand for real-time imaging is presented, and then the simulation is used to analyze the performance of the real-time gated viewing system. The range accuracy performance is limited by the slice number, the width of gate, the delay time step, the initial delay time, as well as the system noise and atmospheric turbulence. The simulation results indicate that the highest range accuracy can be achieved when the system works with the optimal parameters. Finally, how to choose the optimal parameters has been researched.展开更多
In this paper, the response time of all-optical AND logic gate using the triangular photonic crystal lattice is investigated. The proposed logic gate consists of a photonic crystal nano-resonator formed by changing th...In this paper, the response time of all-optical AND logic gate using the triangular photonic crystal lattice is investigated. The proposed logic gate consists of a photonic crystal nano-resonator formed by changing the size of the dielectric rods. The structure benefits the interference effect mechanism. The contrast ratio of the photonic crystal AND logic gate is obtained as 6 d B. In addition to simplicity, the designed nano-resonator increases the bit rate of logic gate. The delay time and footprint of logic gate are respectively 0.32 ps and 146 μm2. The proposed photonic crystal AND logic gate can operate at a bit rate of 3.12 Tbit/s。展开更多
A multi-deposition multi-annealing technique （MDMA） is introduced into the process of high-k/metal gate MOSFET for the gate last process to effectively reduce the gate leakage and improve the device＇s performance. ...A multi-deposition multi-annealing technique （MDMA） is introduced into the process of high-k/metal gate MOSFET for the gate last process to effectively reduce the gate leakage and improve the device＇s performance. In this paper, we systematically investigate the electrical parameters and the time-dependent dielectric breakdown （TDDB） characteristics of positive channel metal oxide semiconductor （PMOS） under different MDMA process conditions, including the depo- sition/annealing （D＆A） cycles, the D＆A time, and the total annealing time. The results show that the increases of the number of D＆A cycles （from 1 to 2） and D＆A time （from 15 s to 30 s） can contribute to the results that the gate leakage current decreases by about one order of magnitude and that the time to fail （TTF） at 63.2% increases by about several times. However, too many D＆A cycles （such as 4 cycles） make the equivalent oxide thickness （EOT） increase by about 1A and the TTF of PMOS worsen. Moreover, different D＆A times and numbers of D＆A cycles induce different breakdown mechanisms.展开更多
Purpose: Respiratory-gated radiation therapy (RT) using the real-time tumor-tracking radiotherapy (RTRT) system is an effective technique for managing tumor motion. High dosimetric and geometric accuracy is needed;how...Purpose: Respiratory-gated radiation therapy (RT) using the real-time tumor-tracking radiotherapy (RTRT) system is an effective technique for managing tumor motion. High dosimetric and geometric accuracy is needed;however, quality assurance (QA) for respiratory-gated RT using the RTRT system has not been reported. The purpose of this study was to perform QA for respiratorygated RT using the RTRT system. Materials and Methods: The RTRT system detected the position of the fiducial marker and radiation delivery gated to the motion of the marker was performed. The dynamic anthropomorphic thorax phantom was positioned at the isocenter using the fiducial marker in the phantom. The phantom was irradiated only when the fiducial marker was within a three-dimensional gating window of ±2 mm from the planned position. First, the absolute doses were measured using anionization chamber inserted in the phantom under the stationary, gating and non-gating state for sinusoidal (nadir-to-peak amplitude [A]: 20 - 40 mm, breathing period [T]: 2 - 4 s) and the basic respiratory patterns. Second, the dose profiles were measured using Gafchromic films in the phantom under the same conditions. Differences between dose profiles were calculated to evaluate the dosimetric and geometric accuracy. Finally, differences between the actual and measured position of the fiducial marker were calculated to evaluate the tracking accuracy for sinusoidal and basic respiratory patterns. Results: For the sinusoidal patterns, the relative doses were 0.93 for non-gating and 0.99 for gating (A = 20 mm, T = 2 s), 0.94 for non-gating and 1.00 for gating (A = 20 mm, T = 4 s), 0.55 for non-gating and 1.00 for gating (A = 40 mm, T = 4 s), respectively. For the basic respiratory pattern, the relative doses were 1.00 for non-gating and 1.00 for gating, respectively. Compared to the stationary conditions, the differences in lateral distance between the 90% dose of dose profiles were 6.23 mm for non-gating and 0.36 mm for gating (A = 20 mm, T = 2 s), 8.79 mm for non-gating and 1.73 mm for gating (A = 20 mm, T = 4 s), 18.37 mm for non-gating and 0.67 mm for gating (A = 40 mm, T = 4 s), respectively. For the basic respiratory pattern, those were 5.23 mm for non-gating and 0.35 mm for gating. The root mean square (RMS) values of the tracking error were 0.18 mm (A = 20 mm, T = 2 s), 0.14 mm (A = 20 mm, T = 4 s), and 0.21 mm (A = 40 mm, T = 4 s) for sinusoidal and 0.79 mm for the basic respiratory pattern, respectively. Conclusion: We conducted QA for respiratory-gated RT using the RTRT system. The respiratory-gated RT using the RTRT system reduced the blurring effects on dose distribution with high dosimetric and geometric accuracy.展开更多
Fluorescence lifetime imaging microscopy(FLIM)is a powerful tool to discriminate fluorescent molecules or probe their nanoscale environment.Traditionally,FLIM uses time-correlated single-photon counting(TCSPC),which i...Fluorescence lifetime imaging microscopy(FLIM)is a powerful tool to discriminate fluorescent molecules or probe their nanoscale environment.Traditionally,FLIM uses time-correlated single-photon counting(TCSPC),which is precise but intrinsically low-throughput due to its dependence on point detectors.Although time-gated cameras have demonstrated the potential for high-throughput FLIM in bright samples with dense labeling,their use in single-molecule microscopy has not been explored extensively.Here,we report fast and accurate single-molecule FLIM with a commercial time-gated single-photon camera.Our optimized acquisition scheme achieves single-molecule lifetime measurements with a precision only about three times less than TCSPC,while imaging with a large number of pixels(512×512)allowing for the spatial multiplexing of over 3000 molecules.With this approach,we demonstrate parallelized lifetime measurements of large numbers of labeled pore-forming proteins on supported lipid bilayers,and temporal single-molecule Förster resonance energy transfer measurements at 5-25 Hz.This method holds considerable promise for the advancement of multi-target single-molecule localization microscopy and biopolymer sequencing.展开更多
基金supported by the Pre-research Foundation under Grant No. G020104PJ09DZ0246
文摘A gated viewing laser radar has an excellent performance in underwater low light level imaging, and it also provides a viable solution to inhibit backscattering. In this paper, a gated viewing imaging system according to the demand for real-time imaging is presented, and then the simulation is used to analyze the performance of the real-time gated viewing system. The range accuracy performance is limited by the slice number, the width of gate, the delay time step, the initial delay time, as well as the system noise and atmospheric turbulence. The simulation results indicate that the highest range accuracy can be achieved when the system works with the optimal parameters. Finally, how to choose the optimal parameters has been researched.
文摘In this paper, the response time of all-optical AND logic gate using the triangular photonic crystal lattice is investigated. The proposed logic gate consists of a photonic crystal nano-resonator formed by changing the size of the dielectric rods. The structure benefits the interference effect mechanism. The contrast ratio of the photonic crystal AND logic gate is obtained as 6 d B. In addition to simplicity, the designed nano-resonator increases the bit rate of logic gate. The delay time and footprint of logic gate are respectively 0.32 ps and 146 μm2. The proposed photonic crystal AND logic gate can operate at a bit rate of 3.12 Tbit/s。
基金supported by the National High Technology Research and Development Program of China(Grant No.SS2015AA010601)the National Natural Science Foundation of China(Grant Nos.61176091 and 61306129)
文摘A multi-deposition multi-annealing technique （MDMA） is introduced into the process of high-k/metal gate MOSFET for the gate last process to effectively reduce the gate leakage and improve the device＇s performance. In this paper, we systematically investigate the electrical parameters and the time-dependent dielectric breakdown （TDDB） characteristics of positive channel metal oxide semiconductor （PMOS） under different MDMA process conditions, including the depo- sition/annealing （D＆A） cycles, the D＆A time, and the total annealing time. The results show that the increases of the number of D＆A cycles （from 1 to 2） and D＆A time （from 15 s to 30 s） can contribute to the results that the gate leakage current decreases by about one order of magnitude and that the time to fail （TTF） at 63.2% increases by about several times. However, too many D＆A cycles （such as 4 cycles） make the equivalent oxide thickness （EOT） increase by about 1A and the TTF of PMOS worsen. Moreover, different D＆A times and numbers of D＆A cycles induce different breakdown mechanisms.
文摘Purpose: Respiratory-gated radiation therapy (RT) using the real-time tumor-tracking radiotherapy (RTRT) system is an effective technique for managing tumor motion. High dosimetric and geometric accuracy is needed;however, quality assurance (QA) for respiratory-gated RT using the RTRT system has not been reported. The purpose of this study was to perform QA for respiratorygated RT using the RTRT system. Materials and Methods: The RTRT system detected the position of the fiducial marker and radiation delivery gated to the motion of the marker was performed. The dynamic anthropomorphic thorax phantom was positioned at the isocenter using the fiducial marker in the phantom. The phantom was irradiated only when the fiducial marker was within a three-dimensional gating window of ±2 mm from the planned position. First, the absolute doses were measured using anionization chamber inserted in the phantom under the stationary, gating and non-gating state for sinusoidal (nadir-to-peak amplitude [A]: 20 - 40 mm, breathing period [T]: 2 - 4 s) and the basic respiratory patterns. Second, the dose profiles were measured using Gafchromic films in the phantom under the same conditions. Differences between dose profiles were calculated to evaluate the dosimetric and geometric accuracy. Finally, differences between the actual and measured position of the fiducial marker were calculated to evaluate the tracking accuracy for sinusoidal and basic respiratory patterns. Results: For the sinusoidal patterns, the relative doses were 0.93 for non-gating and 0.99 for gating (A = 20 mm, T = 2 s), 0.94 for non-gating and 1.00 for gating (A = 20 mm, T = 4 s), 0.55 for non-gating and 1.00 for gating (A = 40 mm, T = 4 s), respectively. For the basic respiratory pattern, the relative doses were 1.00 for non-gating and 1.00 for gating, respectively. Compared to the stationary conditions, the differences in lateral distance between the 90% dose of dose profiles were 6.23 mm for non-gating and 0.36 mm for gating (A = 20 mm, T = 2 s), 8.79 mm for non-gating and 1.73 mm for gating (A = 20 mm, T = 4 s), 18.37 mm for non-gating and 0.67 mm for gating (A = 40 mm, T = 4 s), respectively. For the basic respiratory pattern, those were 5.23 mm for non-gating and 0.35 mm for gating. The root mean square (RMS) values of the tracking error were 0.18 mm (A = 20 mm, T = 2 s), 0.14 mm (A = 20 mm, T = 4 s), and 0.21 mm (A = 40 mm, T = 4 s) for sinusoidal and 0.79 mm for the basic respiratory pattern, respectively. Conclusion: We conducted QA for respiratory-gated RT using the RTRT system. The respiratory-gated RT using the RTRT system reduced the blurring effects on dose distribution with high dosimetric and geometric accuracy.
基金support from the EPFL Center for Imaging(A.R.,N.R.,E.C.and C.B.)European Research Council(grant 101020445 to A.R.)+2 种基金the Swiss National Science Foundation(grant 200021-184687 to G.P.A.,grant 200021L-212128 to M.D.P.and grant IZSEZ0-224299 to R.R.)the National Center of Competence in Research Bio-Inspired Materials(NCCR 51NF40-182881 to G.P.A.and A.R.)the European Union Program HORIZON-Pathfinder-Open(grant 101099125 to G.P.A.).
文摘Fluorescence lifetime imaging microscopy(FLIM)is a powerful tool to discriminate fluorescent molecules or probe their nanoscale environment.Traditionally,FLIM uses time-correlated single-photon counting(TCSPC),which is precise but intrinsically low-throughput due to its dependence on point detectors.Although time-gated cameras have demonstrated the potential for high-throughput FLIM in bright samples with dense labeling,their use in single-molecule microscopy has not been explored extensively.Here,we report fast and accurate single-molecule FLIM with a commercial time-gated single-photon camera.Our optimized acquisition scheme achieves single-molecule lifetime measurements with a precision only about three times less than TCSPC,while imaging with a large number of pixels(512×512)allowing for the spatial multiplexing of over 3000 molecules.With this approach,we demonstrate parallelized lifetime measurements of large numbers of labeled pore-forming proteins on supported lipid bilayers,and temporal single-molecule Förster resonance energy transfer measurements at 5-25 Hz.This method holds considerable promise for the advancement of multi-target single-molecule localization microscopy and biopolymer sequencing.
