The paper studied the relationship between microstructure and shape recovery characteristics by using colored microstructure analysis under polarized light on the thermomechanical cycled CuAlNi single crystals. The tw...The paper studied the relationship between microstructure and shape recovery characteristics by using colored microstructure analysis under polarized light on the thermomechanical cycled CuAlNi single crystals. The two-way shape memory effect in quenched thin bar resulted from the preferential formation/extinction of martensite variant due to the internal quench stress, and the variant was formed at an angle of about 45 deg. with the tension direction ([001] of the βphase). Initial thermomechanical cycling under relatively low stress single variant stress-induced martensite was formed at an angle of 45 deg. with the tension and its morphology was a lath of parallel twins. More than one group of variants were formed after several training cycles and such variants also caused tilting of some thermally formed accommodated martensite. By overheating the trained sample containing stabilized multi-variants of stress-induced martensite, very coarse martensite structure with a strong asymmetry was produced, which caused the reverse two-way shape memory effect.展开更多
Measurement of out-of-plane deformation is significant to understanding of the deflection mechanisms of the plate and tube structures.In this study,a new surface contouring technique with color structured light is app...Measurement of out-of-plane deformation is significant to understanding of the deflection mechanisms of the plate and tube structures.In this study,a new surface contouring technique with color structured light is applied to measure the out-of-plane deformation of structures with one-shot projection.Through color fringe recognizing,decoding and triangulation processing for the captured images corresponding to each deformation state,the feasibility of the method is testified by the measurement of elastic deflections of a flexible square plate,showing good agreement with those from the calibrated displacement driver.The plastic deformation of two alloy aluminum rectangular tubes is measured to show the technique application to surface topographic evaluation of the buckling structures with large displacements.展开更多
A pseudo-white-thermM light source is prepared by projecting three (red, green, and blue) laser beams onto a rotating ground glass disk. Based on the RGB color model, we investigate the color Hanbury-Brown Twiss (H...A pseudo-white-thermM light source is prepared by projecting three (red, green, and blue) laser beams onto a rotating ground glass disk. Based on the RGB color model, we investigate the color Hanbury-Brown Twiss (HI)T) effect and color ghost imaging with thermal light. The color HBT effect indicates that photons of the same color will bunch. This fact ensures the chromatic discrimination power of ghost imaging with thermM light. We retrieve the RGB ingredients of the object through intensity correlation measurements. A method of white balance to properly form the ghost images is proposed,展开更多
We investigated an interaction effect between lighting color and food color that stimulates or discourages one's appetite. Facilitated by the LED (light-emitting diode) as an additional chromatic lighting source, o...We investigated an interaction effect between lighting color and food color that stimulates or discourages one's appetite. Facilitated by the LED (light-emitting diode) as an additional chromatic lighting source, observers selected the best and worst lighting colors by themselves using a "Mini Living Colors (PhilipsTM)" in the preliminary test (N = 30) and then color picker software in the main experiment (N = 30). Food stimuli were composed of two aspects, type--natural or processed--and complexity--low or high, and consequently they were grouped into four categories. We measured the selected lighting color in terms of chromaticity and illumination level, and analyzed the best and worst combinations based on these measurements. Throughout the two empirical studies, we found three tendencies: First, except for the white, yellow lighting stimulates while red and blue discourages one's appetite. Second, when color categories of lighting and food are similar to each other, it stimulates the appetite whereas complementary, it discourages it. Third, the type of food does not act as an influencing factor.展开更多
Rainbow particle image velocimetry(PIV)can restore the three-dimensional velocity field of particles with a single camera;however,it requires a relatively long time to complete the reconstruction.This paper proposes a...Rainbow particle image velocimetry(PIV)can restore the three-dimensional velocity field of particles with a single camera;however,it requires a relatively long time to complete the reconstruction.This paper proposes a hybrid algorithm that combines the fast Fourier transform(FFT)based co-correlation algorithm and the Horn–Schunck(HS)optical flow pyramid iterative algorithm to increase the reconstruction speed.The Rankine vortex simulation experiment was performed,in which the particle velocity field was reconstructed using the proposed algorithm and the rainbow PIV method.The average endpoint error and average angular error of the proposed algorithm were roughly the same as those of the rainbow PIV algorithm;nevertheless,the reconstruction time was 20%shorter.Furthermore,the effect of velocity magnitude and particle density on the reconstruction results was analyzed.In the end,the performance of the proposed algorithm was verified using real experimental single-vortex and double-vortex datasets,from which a similar particle velocity field was obtained compared with the rainbow PIV algorithm.The results show that the reconstruction speed of the proposed hybrid algorithm is approximately 25%faster than that of the rainbow PIV algorithm.展开更多
Light emitting diode(LED) is the fourth generation lighting source,but it has some shortcomings such as complex chip packaging process and the unbalanced light color of phosphor in long-time application.In this study,...Light emitting diode(LED) is the fourth generation lighting source,but it has some shortcomings such as complex chip packaging process and the unbalanced light color of phosphor in long-time application.In this study,a kind of Eu-terephthalic acid/Tb-sulfosalicylate/ZrO_(2)/ZnZrO_(3)(Eu-PTA/Tb-SSA/ZrO_(2)/ZnZrO_(3))phosphor with warm white light emission properties was prepared,and the warm white light LED(wWLEDs) was successfully prepared by encapsulating Eu-PTA/Tb-SSA/ZrO_(2)/ZnZrO_(3) phosphors together with 270 nm UV-chip.The ZrO_(2)/ZnZrO_(3),Tb-SSA/ZrO_(2)/ZnZrO_(3) and Eu-PTA/ZrO_(2)/ZnZrO_(3) samples show blue emission,green emission and red emission under deep ultraviolet(UV,270 nm) excitation,respectively.The Tb-SSA and Eu-PTA are co-doped into ZrO_(2)/ZnZrO_(3) matrix with blue emission to achieve the warm white light emission,and the light color can be adjusted by controlling the doping amount of Eu^(3+)-and Tb^(3+).Through the excitation method of single-component phosphor by the single chip,the complex chip packaging process of w-LED can be solved.By doping rare earth organic complexes into porous ZrO_(2)/ZnZrO_(3) matrix,the problems of the light color unbalanced of phosphor and the low luminescence intensity of rare earth doped metal oxides composites can be solved.展开更多
This paper addresses the issue of managing the traffic flow at traffic-light controlled junctions adopting a mixed,nonlinear programming model.More precisely,we adopt an adaptive,acyclic control system based on the ge...This paper addresses the issue of managing the traffic flow at traffic-light controlled junctions adopting a mixed,nonlinear programming model.More precisely,we adopt an adaptive,acyclic control system based on the genetic algorithm(GA),a system that allows to accurately decide in real time on the light switching pattern that minimizes the traffic waiting time.Equally importantly,the inherent crossroads constraints,namely,the security of their users and the structure thereof,also referred to as the antagonism principle,are considered in the proceeding of this method.The implementation of this model on two crossroads significantly decreases the waiting time and regulates the traffic flow.Therefore,the adaptive control system based on the GA proves efficient compared to the nonadaptive system.展开更多
文摘The paper studied the relationship between microstructure and shape recovery characteristics by using colored microstructure analysis under polarized light on the thermomechanical cycled CuAlNi single crystals. The two-way shape memory effect in quenched thin bar resulted from the preferential formation/extinction of martensite variant due to the internal quench stress, and the variant was formed at an angle of about 45 deg. with the tension direction ([001] of the βphase). Initial thermomechanical cycling under relatively low stress single variant stress-induced martensite was formed at an angle of 45 deg. with the tension and its morphology was a lath of parallel twins. More than one group of variants were formed after several training cycles and such variants also caused tilting of some thermally formed accommodated martensite. By overheating the trained sample containing stabilized multi-variants of stress-induced martensite, very coarse martensite structure with a strong asymmetry was produced, which caused the reverse two-way shape memory effect.
文摘Measurement of out-of-plane deformation is significant to understanding of the deflection mechanisms of the plate and tube structures.In this study,a new surface contouring technique with color structured light is applied to measure the out-of-plane deformation of structures with one-shot projection.Through color fringe recognizing,decoding and triangulation processing for the captured images corresponding to each deformation state,the feasibility of the method is testified by the measurement of elastic deflections of a flexible square plate,showing good agreement with those from the calibrated displacement driver.The plastic deformation of two alloy aluminum rectangular tubes is measured to show the technique application to surface topographic evaluation of the buckling structures with large displacements.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11047004,11204062 and 11174038the National High-Technology Research and Development Program of China under Grant No 2013AA122902the Youth Foundation of Hebei Educational Committee under Grant No QN2014086
文摘A pseudo-white-thermM light source is prepared by projecting three (red, green, and blue) laser beams onto a rotating ground glass disk. Based on the RGB color model, we investigate the color Hanbury-Brown Twiss (HI)T) effect and color ghost imaging with thermal light. The color HBT effect indicates that photons of the same color will bunch. This fact ensures the chromatic discrimination power of ghost imaging with thermM light. We retrieve the RGB ingredients of the object through intensity correlation measurements. A method of white balance to properly form the ghost images is proposed,
文摘We investigated an interaction effect between lighting color and food color that stimulates or discourages one's appetite. Facilitated by the LED (light-emitting diode) as an additional chromatic lighting source, observers selected the best and worst lighting colors by themselves using a "Mini Living Colors (PhilipsTM)" in the preliminary test (N = 30) and then color picker software in the main experiment (N = 30). Food stimuli were composed of two aspects, type--natural or processed--and complexity--low or high, and consequently they were grouped into four categories. We measured the selected lighting color in terms of chromaticity and illumination level, and analyzed the best and worst combinations based on these measurements. Throughout the two empirical studies, we found three tendencies: First, except for the white, yellow lighting stimulates while red and blue discourages one's appetite. Second, when color categories of lighting and food are similar to each other, it stimulates the appetite whereas complementary, it discourages it. Third, the type of food does not act as an influencing factor.
基金the National Natural Science Foundation of China(Grant Nos.51874264 and 52076200)。
文摘Rainbow particle image velocimetry(PIV)can restore the three-dimensional velocity field of particles with a single camera;however,it requires a relatively long time to complete the reconstruction.This paper proposes a hybrid algorithm that combines the fast Fourier transform(FFT)based co-correlation algorithm and the Horn–Schunck(HS)optical flow pyramid iterative algorithm to increase the reconstruction speed.The Rankine vortex simulation experiment was performed,in which the particle velocity field was reconstructed using the proposed algorithm and the rainbow PIV method.The average endpoint error and average angular error of the proposed algorithm were roughly the same as those of the rainbow PIV algorithm;nevertheless,the reconstruction time was 20%shorter.Furthermore,the effect of velocity magnitude and particle density on the reconstruction results was analyzed.In the end,the performance of the proposed algorithm was verified using real experimental single-vortex and double-vortex datasets,from which a similar particle velocity field was obtained compared with the rainbow PIV algorithm.The results show that the reconstruction speed of the proposed hybrid algorithm is approximately 25%faster than that of the rainbow PIV algorithm.
基金supported by the National Natural Science Foundation of China (51572034)the Jilin Province Science and Technology Development Plan Project of China (20220203168SF)。
文摘Light emitting diode(LED) is the fourth generation lighting source,but it has some shortcomings such as complex chip packaging process and the unbalanced light color of phosphor in long-time application.In this study,a kind of Eu-terephthalic acid/Tb-sulfosalicylate/ZrO_(2)/ZnZrO_(3)(Eu-PTA/Tb-SSA/ZrO_(2)/ZnZrO_(3))phosphor with warm white light emission properties was prepared,and the warm white light LED(wWLEDs) was successfully prepared by encapsulating Eu-PTA/Tb-SSA/ZrO_(2)/ZnZrO_(3) phosphors together with 270 nm UV-chip.The ZrO_(2)/ZnZrO_(3),Tb-SSA/ZrO_(2)/ZnZrO_(3) and Eu-PTA/ZrO_(2)/ZnZrO_(3) samples show blue emission,green emission and red emission under deep ultraviolet(UV,270 nm) excitation,respectively.The Tb-SSA and Eu-PTA are co-doped into ZrO_(2)/ZnZrO_(3) matrix with blue emission to achieve the warm white light emission,and the light color can be adjusted by controlling the doping amount of Eu^(3+)-and Tb^(3+).Through the excitation method of single-component phosphor by the single chip,the complex chip packaging process of w-LED can be solved.By doping rare earth organic complexes into porous ZrO_(2)/ZnZrO_(3) matrix,the problems of the light color unbalanced of phosphor and the low luminescence intensity of rare earth doped metal oxides composites can be solved.
文摘This paper addresses the issue of managing the traffic flow at traffic-light controlled junctions adopting a mixed,nonlinear programming model.More precisely,we adopt an adaptive,acyclic control system based on the genetic algorithm(GA),a system that allows to accurately decide in real time on the light switching pattern that minimizes the traffic waiting time.Equally importantly,the inherent crossroads constraints,namely,the security of their users and the structure thereof,also referred to as the antagonism principle,are considered in the proceeding of this method.The implementation of this model on two crossroads significantly decreases the waiting time and regulates the traffic flow.Therefore,the adaptive control system based on the GA proves efficient compared to the nonadaptive system.