This letter introduces a simple model to explain the Diffraction and Interference of Light. It was created using only a corpuscular point of view. The mean concept of the model introduced in this paper is that light h...This letter introduces a simple model to explain the Diffraction and Interference of Light. It was created using only a corpuscular point of view. The mean concept of the model introduced in this paper is that light has two independent states of polarization that oscillate with equal frequencies but with a π/2 difference of phase. This model allows the author to determine the intensity of light at any point after it exceeds no edge or any number of them.展开更多
Railway bridges are susceptible to over-height truck collisions and to address this issue,it is necessary to attenuate the effect of these impacts to ensure the safety of transportation operations.This study experimen...Railway bridges are susceptible to over-height truck collisions and to address this issue,it is necessary to attenuate the effect of these impacts to ensure the safety of transportation operations.This study experimentally investigates the effectiveness of crash beams as a cushioning mechanism for railway bridges against collisions.Over-height truck and railway bridge impact events were simulated in a 1:5 scale experiment.The design parameters such as the stiffness of the crash beam and the bridge supports were scaled to evaluate different levels of attenuation.Seventeen experiments were conducted with five configurations consisting of four different types of crash beams and one no-crash beam arrangement.The results show that crash beams attenuate bridge total peak dynamic displacement responses between 14.5%and 35.7%,depending on the intensity of the impact and crash beam type.In addition,the results show that the average effectiveness in attenuating residual deformation for all four crash beams ranges from 43.03%to 83.40%.Finally,various designs and their effectiveness against lateral impacts with different speeds are discussed.The overall scope of this research is to provide objective information about the design of crash beams for railway bridges based on their response to over-height truck collisions at various speeds.展开更多
Micro/nano biosensors had rapidly progressed and enabled a verity of applications that were otherwise impossible/challenging with traditional methods.The three key components in micro/nano biosensors consist of(1)the ...Micro/nano biosensors had rapidly progressed and enabled a verity of applications that were otherwise impossible/challenging with traditional methods.The three key components in micro/nano biosensors consist of(1)the analyte preparation(living cells or biomarker molecules),(2)signal transduction(from bio-signal/event to more readable electronic/optical signal),and(3)signal readout(preferably by integrated instrumentation).A verity of work has been dedicated to each of these three areas.It is now evident that micro/nanotechnology is playing a significant role in the development of cell and molecule biosensors.The performance of biosensors was significantly enhanced by combining the micro/nanostructures,which present unique physical and chemical characteristics due to various effects at these scales.展开更多
The production of maxima and minima by the superposition of two or more light signals provides fundamental support for the wave nature of light. This result is based on the study of wave interference phenomena which r...The production of maxima and minima by the superposition of two or more light signals provides fundamental support for the wave nature of light. This result is based on the study of wave interference phenomena which remains the only approach to explain the production of those maxima and minima. In a system that is prepared to work with only one photon at a time, any detector can signal only one or zero. In 1986, a rigorously controlled experiment was designed by Grangier, G. Roger, and A. Aspect, [Europhys Lett. 1(4), p. 173, 1986] that guaranteed a single-photon beam. The explanation of the experimental results implied the interference of the wave function of a single-photon with itself. Thus, the explanation of interference that is accepted for an ensemble of photons was assumed to be valid for a single photon. In this study, we prepare a Mach-Zehnder interferometer using the same type of beam splitters used by Grangier et al. to test the assumption mentioned above. Our results allow us to explain the results of Grangier et al. because of the interaction between light and the beam splitters. Our results also verify that their wave interpretation of the results is not valid. Here, we present the essential findings of the extensive experimental evidence that supports our ideas.展开更多
Whether it’s political or personal, people have been writing on walls for centuries.From ancient murals in caves to modern day‘bombings’ in subways, graffiti is an
Music videos were visually non-existent thirty years ago until the emergence of music television programs.By the mid- 1980s,they ruled over the music industry proving that a video is as important as the song itself,so...Music videos were visually non-existent thirty years ago until the emergence of music television programs.By the mid- 1980s,they ruled over the music industry proving that a video is as important as the song itself,sometimes even determining the success of an artist.展开更多
文摘This letter introduces a simple model to explain the Diffraction and Interference of Light. It was created using only a corpuscular point of view. The mean concept of the model introduced in this paper is that light has two independent states of polarization that oscillate with equal frequencies but with a π/2 difference of phase. This model allows the author to determine the intensity of light at any point after it exceeds no edge or any number of them.
基金Scientific Research Fund of Institute of Engineering Mechanics,China Earthquake Administration under Grant Nos.2016A06 and 2017A02the National Natural Science Foundation of China under Grant Nos.51678538 and 51878630+1 种基金the Transportation Consortium of South-Central States(TRANSET)US Department of Transportation(USDOT),Project No.17STUNM02。
文摘Railway bridges are susceptible to over-height truck collisions and to address this issue,it is necessary to attenuate the effect of these impacts to ensure the safety of transportation operations.This study experimentally investigates the effectiveness of crash beams as a cushioning mechanism for railway bridges against collisions.Over-height truck and railway bridge impact events were simulated in a 1:5 scale experiment.The design parameters such as the stiffness of the crash beam and the bridge supports were scaled to evaluate different levels of attenuation.Seventeen experiments were conducted with five configurations consisting of four different types of crash beams and one no-crash beam arrangement.The results show that crash beams attenuate bridge total peak dynamic displacement responses between 14.5%and 35.7%,depending on the intensity of the impact and crash beam type.In addition,the results show that the average effectiveness in attenuating residual deformation for all four crash beams ranges from 43.03%to 83.40%.Finally,various designs and their effectiveness against lateral impacts with different speeds are discussed.The overall scope of this research is to provide objective information about the design of crash beams for railway bridges based on their response to over-height truck collisions at various speeds.
文摘Micro/nano biosensors had rapidly progressed and enabled a verity of applications that were otherwise impossible/challenging with traditional methods.The three key components in micro/nano biosensors consist of(1)the analyte preparation(living cells or biomarker molecules),(2)signal transduction(from bio-signal/event to more readable electronic/optical signal),and(3)signal readout(preferably by integrated instrumentation).A verity of work has been dedicated to each of these three areas.It is now evident that micro/nanotechnology is playing a significant role in the development of cell and molecule biosensors.The performance of biosensors was significantly enhanced by combining the micro/nanostructures,which present unique physical and chemical characteristics due to various effects at these scales.
文摘The production of maxima and minima by the superposition of two or more light signals provides fundamental support for the wave nature of light. This result is based on the study of wave interference phenomena which remains the only approach to explain the production of those maxima and minima. In a system that is prepared to work with only one photon at a time, any detector can signal only one or zero. In 1986, a rigorously controlled experiment was designed by Grangier, G. Roger, and A. Aspect, [Europhys Lett. 1(4), p. 173, 1986] that guaranteed a single-photon beam. The explanation of the experimental results implied the interference of the wave function of a single-photon with itself. Thus, the explanation of interference that is accepted for an ensemble of photons was assumed to be valid for a single photon. In this study, we prepare a Mach-Zehnder interferometer using the same type of beam splitters used by Grangier et al. to test the assumption mentioned above. Our results allow us to explain the results of Grangier et al. because of the interaction between light and the beam splitters. Our results also verify that their wave interpretation of the results is not valid. Here, we present the essential findings of the extensive experimental evidence that supports our ideas.
文摘Whether it’s political or personal, people have been writing on walls for centuries.From ancient murals in caves to modern day‘bombings’ in subways, graffiti is an
文摘Music videos were visually non-existent thirty years ago until the emergence of music television programs.By the mid- 1980s,they ruled over the music industry proving that a video is as important as the song itself,sometimes even determining the success of an artist.
