We predict the possibility of the interference of narrow-band biphotons generated by spontaneous four-wave mixing with double electromagnetically induced transparency configuration in cold atoms.In an N-type fourlevel...We predict the possibility of the interference of narrow-band biphotons generated by spontaneous four-wave mixing with double electromagnetically induced transparency configuration in cold atoms.In an N-type fourlevel system,an auxiliary optical field Ωm can create double transparency windows for anti-Stokes photons.When the slow light effects in the double transparency windows are very strong,two four-wave mixing channels could exist due to the splitting of the phase matching condition.The biphoton generated from the two four-wave mixing channels can cause interference and shows Rabi oscillations in two-photon correlation.This interference mechanism will complement the understanding of interference at the two-photon level.展开更多
Electronic skin made of thin,soft,stretchable devices that can mimic the human skin and reconstruct the tactile sensation and perception offers great opportunities for prosthesis sensing,robotics controlling,and human...Electronic skin made of thin,soft,stretchable devices that can mimic the human skin and reconstruct the tactile sensation and perception offers great opportunities for prosthesis sensing,robotics controlling,and human-machine interfaces.Advanced materials and mechanics engineering of thin film devices has proven to be an efficient route to enable and enhance flexibility and stretchability of various electronic skins;however,the density of devices is still low owing to the limitation in existing fabrication techniques.Here,we report a high-throughput one-step process to fabricate large tactile sensing arrays with a sensor density of 25 sensors/cm^(2) for electronic skin,where the sensors are based on intrinsically stretchable piezoelectric lead zirconate titanate(PZT)elastomer.The PZT elastomer sensor arrays with great uniformity and passive-driven manner enable highresolution tactile sensing,simplify the data acquisition process,and lower the manufacturing cost.The high-throughput fabrication process provides a general platform for integrating intrinsically stretchable materials into large area,high device density soft electronics for the next-generation electronic skin.展开更多
As the science and technology develop,crime methods and scenes have become increasingly complex and diverse.Trace evidence analysis has become amore and more important criminal investigation technology and liquid is t...As the science and technology develop,crime methods and scenes have become increasingly complex and diverse.Trace evidence analysis has become amore and more important criminal investigation technology and liquid is the main form of trace evidence.Food can provide not only energy,but clues to solve crimes.In this study,we build a hyperspectral imaging system to detect liquid residue traces,including apple juice,coffee,cola,milk and tea,on denims with light,middle and dark colors.The obtained hyperspectral images are first subjected to spectral calibration and hyperspectral data pretreatment.Subsequently,Partial Least Squares(PLS)is applied to select the informative wavelengths from the preprocessed spectra.For modeling phase,the combination optimal strategy,support vector machine(SVM)combined with random forest(RF),is developed to establish classification models.The experimental results demonstrate that the combination optimal model can achieve TPR,FPR,Precision,Recall,F1,and AUC of 83.5%,2.30%,79.7%,83.5%,81.6%,and 94.7%for classifying fabrics contaminated by various food residuals.With respect to the classification of liquid and fabric types,the combination optimalmodel also yields satisfactory classification performance.In future work,wewill expand the types of liquid,and make appropriate adjustment to algorithms for improving the robustness of classification models.This research may play a positive role in the construction of a harmonious society.展开更多
■INTRODUCTION The differences between built and biological machines are innumerable.For example,robots struggle to adapt to and engage with real-world environments,whereas living organisms effortlessly do so.Unlike t...■INTRODUCTION The differences between built and biological machines are innumerable.For example,robots struggle to adapt to and engage with real-world environments,whereas living organisms effortlessly do so.Unlike the multifunctional behaviors of living organisms,robots’capabilities possess limited versatility.Living organisms source energy from their environment,while robots face nontrivial power and computational challenges that complicate their remote deployment.展开更多
Recent progress in the synthesis and deterministic assembly of advanced classes of single crystalline inorganic semiconductor nanomaterial establishes a foundation for high-performance electronics on bendable,and even...Recent progress in the synthesis and deterministic assembly of advanced classes of single crystalline inorganic semiconductor nanomaterial establishes a foundation for high-performance electronics on bendable,and even elastomeric,substrates.The results allow for classes of systems with capabilities that cannot be reproduced using conventional wafer-based technologies.Specifically,electronic devices that rely on the unusual shapes/forms/constructs of such semiconductors can offer mechanical properties,such as flexibility and stretchability,traditionally believed to be accessible only via comparatively low-performance organic materials,with superior operational features due to their excellent charge transport characteristics.Specifically,these approaches allow integration of high-performance electronic functionality onto various curvilinear shapes,with linear elastic mechanical responses to large strain deformations,of particular relevance in bio-integrated devices and bio-inspired designs.This review summarizes some recent progress in flexible electronics based on inorganic semiconductor nanomaterials,the key associated design strategies and examples of device components and modules with utility in biomedicine.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 10804115the National Basic Research Program of China under Grant Nos 2006CB921202 and 2011CB921504the Knowledge Innovation Project of the Chinese Academy of Sciences,and the Shanghai Committee of Science and Technology(No 09DJ1400700).
文摘We predict the possibility of the interference of narrow-band biphotons generated by spontaneous four-wave mixing with double electromagnetically induced transparency configuration in cold atoms.In an N-type fourlevel system,an auxiliary optical field Ωm can create double transparency windows for anti-Stokes photons.When the slow light effects in the double transparency windows are very strong,two four-wave mixing channels could exist due to the splitting of the phase matching condition.The biphoton generated from the two four-wave mixing channels can cause interference and shows Rabi oscillations in two-photon correlation.This interference mechanism will complement the understanding of interference at the two-photon level.
基金This work was supported by the City University of Hong Kong(Grant Nos.9610423,9667199)Research Grants Council of the Hong Kong Special Administrative Region(Grant No.21210820)+2 种基金Department of Science and Technology of Sichuan Province(Grant No.2020YFH0181)Z.X.acknowledges the support from the National Natural Science Foundation of China(Grant No.12072057)Fundamental Research Funds for the Central Universities(Grant No.DUT20RC(3)032).
文摘Electronic skin made of thin,soft,stretchable devices that can mimic the human skin and reconstruct the tactile sensation and perception offers great opportunities for prosthesis sensing,robotics controlling,and human-machine interfaces.Advanced materials and mechanics engineering of thin film devices has proven to be an efficient route to enable and enhance flexibility and stretchability of various electronic skins;however,the density of devices is still low owing to the limitation in existing fabrication techniques.Here,we report a high-throughput one-step process to fabricate large tactile sensing arrays with a sensor density of 25 sensors/cm^(2) for electronic skin,where the sensors are based on intrinsically stretchable piezoelectric lead zirconate titanate(PZT)elastomer.The PZT elastomer sensor arrays with great uniformity and passive-driven manner enable highresolution tactile sensing,simplify the data acquisition process,and lower the manufacturing cost.The high-throughput fabrication process provides a general platform for integrating intrinsically stretchable materials into large area,high device density soft electronics for the next-generation electronic skin.
基金sponsored by the National Natural Science Foundation of China(No.61901172,No.61831015,No.U1908210)the Shanghai Sailing Program(No.19YF1414100)+3 种基金the“Chenguang Program”supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.19CG27)the Science and Technology Commission of Shanghai Municipality(No.19511120100,No.18DZ2270700,No.18DZ2270800)the foundation of Key Laboratory of Artificial Intelligence,Ministry of Education(No.AI2019002)and the Fundamental Research Funds for the Central Universities.
文摘As the science and technology develop,crime methods and scenes have become increasingly complex and diverse.Trace evidence analysis has become amore and more important criminal investigation technology and liquid is the main form of trace evidence.Food can provide not only energy,but clues to solve crimes.In this study,we build a hyperspectral imaging system to detect liquid residue traces,including apple juice,coffee,cola,milk and tea,on denims with light,middle and dark colors.The obtained hyperspectral images are first subjected to spectral calibration and hyperspectral data pretreatment.Subsequently,Partial Least Squares(PLS)is applied to select the informative wavelengths from the preprocessed spectra.For modeling phase,the combination optimal strategy,support vector machine(SVM)combined with random forest(RF),is developed to establish classification models.The experimental results demonstrate that the combination optimal model can achieve TPR,FPR,Precision,Recall,F1,and AUC of 83.5%,2.30%,79.7%,83.5%,81.6%,and 94.7%for classifying fabrics contaminated by various food residuals.With respect to the classification of liquid and fabric types,the combination optimalmodel also yields satisfactory classification performance.In future work,wewill expand the types of liquid,and make appropriate adjustment to algorithms for improving the robustness of classification models.This research may play a positive role in the construction of a harmonious society.
文摘■INTRODUCTION The differences between built and biological machines are innumerable.For example,robots struggle to adapt to and engage with real-world environments,whereas living organisms effortlessly do so.Unlike the multifunctional behaviors of living organisms,robots’capabilities possess limited versatility.Living organisms source energy from their environment,while robots face nontrivial power and computational challenges that complicate their remote deployment.
基金the Yonsei University Future-leading Research Initiative of 2017(RMS22017-22-00).
文摘Recent progress in the synthesis and deterministic assembly of advanced classes of single crystalline inorganic semiconductor nanomaterial establishes a foundation for high-performance electronics on bendable,and even elastomeric,substrates.The results allow for classes of systems with capabilities that cannot be reproduced using conventional wafer-based technologies.Specifically,electronic devices that rely on the unusual shapes/forms/constructs of such semiconductors can offer mechanical properties,such as flexibility and stretchability,traditionally believed to be accessible only via comparatively low-performance organic materials,with superior operational features due to their excellent charge transport characteristics.Specifically,these approaches allow integration of high-performance electronic functionality onto various curvilinear shapes,with linear elastic mechanical responses to large strain deformations,of particular relevance in bio-integrated devices and bio-inspired designs.This review summarizes some recent progress in flexible electronics based on inorganic semiconductor nanomaterials,the key associated design strategies and examples of device components and modules with utility in biomedicine.