Aero-optical effects caused by hypersonic turbulence will affect the accuracy of optical sensors ... more Aero-optical effects caused by hypersonic turbulence will affect the accuracy of optical sensors on aircraft. Traditional analysis methods, which do not consider absorption and scattering effects, cannot easily be used to completely describe the transmission process of light in hypersonic turbulence. In this paper, an aero-optical effect analysis method based on photon Monte Carlo simulation (MC-AOEA) was proposed to explain the distortion characteristics of aero-optical effects from the perspective of photon statistics. The energy distribution of photons in the transmission process was determined by taking a photon packet as a unit, and the microscopic statistics of the photon dissipation energy for all photon packets were calculated. The effectiveness of this method was verified by comparing the photon statistical parameters with the traditional optical distortion physical quantities. MC-AOEA was used to analyze the distortion of aero-optical effects at different altitudes and spe...
Aero-optical effects are the key factors that restrict the accuracy of the optical sensors of hyp... more Aero-optical effects are the key factors that restrict the accuracy of the optical sensors of hypersonic vehicles, and the numerical simulation of aero-optical effects is a powerful tool with which to analyze aero-optical distortion. Most existing research focuses on the simulation analysis of refraction distortion based on the density field at the macro level via the ray-tracing method. In this paper, a method for analyzing aero-optical effects based on the interaction between photons and gas molecules is proposed and can explain the optical distortion and energy dissipation caused by aero-optical effects at the micro level. By establishing a transmission model of photons in turbulence, a simulation method of aero-optical effects based on a microscopic mechanism is designed and breaks through the limitations of a traditional macro method in energy analyses. The optical distortion parameters based on photonics are compared with the physical quantities of traditional aero-optical eff...
Purpose: This survey was conducted to identify factors that may be associated with changes in kno... more Purpose: This survey was conducted to identify factors that may be associated with changes in knowledge and attitudes towards basic health promotion and public health concepts among chiropractic students enrolled in a course in community health. Methods: Anonymous surveys were conducted of students before and after a second-year chiropractic college course in community health. Results were analyzed using percentages and Chi Square statistics as appropriate. Results: Students' knowledge of health promotion and public health concepts improved significantly by the end of the course. Students' attitudes towards these also improved, although to a lesser degree. Students indicated that they had a favorable impression of the importance of utilizing health promotion in practice and working with other public health professionals. However, vaccinations were still looked upon unfavorably by half of the students by the end of the course. Pre-class, a positive attitude towards public health concepts was associated with being female, older, Latino, having children, having a poorer perceived health status, conservative politically and religious. These differences tended to lessen by the end of the course. Conclusions: A course in community health was successful in adding to students' knowledge and positive attitudes towards health promotion and public health. However, additional educational strategies are needed to ensure changes in future practice behavior, particularly in the area of vaccinations.
Regulating green electroluminescence (EL) of ZnO is an important but difficult task to produce wh... more Regulating green electroluminescence (EL) of ZnO is an important but difficult task to produce white-light sources due to its strong background green emission. We have demonstrated that the green EL from solutionprocessed ZnO nanocrystals (NCs) can be improved and manipulated by erbium (Er) doping. Er 3+ ions can be doped and activated without any high-temperature post-annealing treatment. Incorporation of the Er 3+ ions in the ZnO host induces lattice expansion primarily along the (002) direction. Er 3+-related characteristic green emissions are observed at 535 and 556 nm and manipulated with increasing Er concentration under forward bias. The EL mechanism is investigated and found to be driven by the energy transfer from the deep-level defects of the ZnO NCs to the nearby Er 3+ ions. Our findings have demonstrated the feasibility of producing green lightemitting diodes by solution-processable Er-doped ZnO NCs and inspired a promising way to develop white-light sources based on printable ZnO NCs simply by incorporating different rare earth ions into the ZnO NCs simultaneously.
Aero-optical effects caused by hypersonic turbulence will affect the accuracy of optical sensors ... more Aero-optical effects caused by hypersonic turbulence will affect the accuracy of optical sensors on aircraft. Traditional analysis methods, which do not consider absorption and scattering effects, cannot easily be used to completely describe the transmission process of light in hypersonic turbulence. In this paper, an aero-optical effect analysis method based on photon Monte Carlo simulation (MC-AOEA) was proposed to explain the distortion characteristics of aero-optical effects from the perspective of photon statistics. The energy distribution of photons in the transmission process was determined by taking a photon packet as a unit, and the microscopic statistics of the photon dissipation energy for all photon packets were calculated. The effectiveness of this method was verified by comparing the photon statistical parameters with the traditional optical distortion physical quantities. MC-AOEA was used to analyze the distortion of aero-optical effects at different altitudes and spe...
Aero-optical effects are the key factors that restrict the accuracy of the optical sensors of hyp... more Aero-optical effects are the key factors that restrict the accuracy of the optical sensors of hypersonic vehicles, and the numerical simulation of aero-optical effects is a powerful tool with which to analyze aero-optical distortion. Most existing research focuses on the simulation analysis of refraction distortion based on the density field at the macro level via the ray-tracing method. In this paper, a method for analyzing aero-optical effects based on the interaction between photons and gas molecules is proposed and can explain the optical distortion and energy dissipation caused by aero-optical effects at the micro level. By establishing a transmission model of photons in turbulence, a simulation method of aero-optical effects based on a microscopic mechanism is designed and breaks through the limitations of a traditional macro method in energy analyses. The optical distortion parameters based on photonics are compared with the physical quantities of traditional aero-optical eff...
Purpose: This survey was conducted to identify factors that may be associated with changes in kno... more Purpose: This survey was conducted to identify factors that may be associated with changes in knowledge and attitudes towards basic health promotion and public health concepts among chiropractic students enrolled in a course in community health. Methods: Anonymous surveys were conducted of students before and after a second-year chiropractic college course in community health. Results were analyzed using percentages and Chi Square statistics as appropriate. Results: Students' knowledge of health promotion and public health concepts improved significantly by the end of the course. Students' attitudes towards these also improved, although to a lesser degree. Students indicated that they had a favorable impression of the importance of utilizing health promotion in practice and working with other public health professionals. However, vaccinations were still looked upon unfavorably by half of the students by the end of the course. Pre-class, a positive attitude towards public health concepts was associated with being female, older, Latino, having children, having a poorer perceived health status, conservative politically and religious. These differences tended to lessen by the end of the course. Conclusions: A course in community health was successful in adding to students' knowledge and positive attitudes towards health promotion and public health. However, additional educational strategies are needed to ensure changes in future practice behavior, particularly in the area of vaccinations.
Regulating green electroluminescence (EL) of ZnO is an important but difficult task to produce wh... more Regulating green electroluminescence (EL) of ZnO is an important but difficult task to produce white-light sources due to its strong background green emission. We have demonstrated that the green EL from solutionprocessed ZnO nanocrystals (NCs) can be improved and manipulated by erbium (Er) doping. Er 3+ ions can be doped and activated without any high-temperature post-annealing treatment. Incorporation of the Er 3+ ions in the ZnO host induces lattice expansion primarily along the (002) direction. Er 3+-related characteristic green emissions are observed at 535 and 556 nm and manipulated with increasing Er concentration under forward bias. The EL mechanism is investigated and found to be driven by the energy transfer from the deep-level defects of the ZnO NCs to the nearby Er 3+ ions. Our findings have demonstrated the feasibility of producing green lightemitting diodes by solution-processable Er-doped ZnO NCs and inspired a promising way to develop white-light sources based on printable ZnO NCs simply by incorporating different rare earth ions into the ZnO NCs simultaneously.
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