With the wide application of drone technology,there is an increasing demand for the detection of radar return signals from drones.Existing detection methods mainly rely on time-frequency domain feature extraction and ...With the wide application of drone technology,there is an increasing demand for the detection of radar return signals from drones.Existing detection methods mainly rely on time-frequency domain feature extraction and classical machine learning algorithms for image recognition.This method suffers from the problem of large dimensionality of image features,which leads to large input data size and noise affecting learning.Therefore,this paper proposes to extract signal time-domain statistical features for radar return signals from drones and reduce the feature dimension from 512×4 to 16 dimensions.However,the downscaled feature data makes the accuracy of traditional machine learning algorithms decrease,so we propose a new hybrid quantum neural network with signal feature overlay projection(HQNN-SFOP),which reduces the dimensionality of the signal by extracting the statistical features in the time domain of the signal,introduces the signal feature overlay projection to enhance the expression ability of quantum computation on the signal features,and introduces the quantum circuits to improve the neural network’s ability to obtain the inline relationship of features,thus improving the accuracy and migration generalization ability of drone detection.In order to validate the effectiveness of the proposed method,we experimented with the method using the MM model that combines the real parameters of five commercial drones and random drones parameters to generate data to simulate a realistic environment.The results show that the method based on statistical features in the time domain of the signal is able to extract features at smaller scales and obtain higher accuracy on a dataset with an SNR of 10 dB.On the time-domain feature data set,HQNNSFOP obtains the highest accuracy compared to other conventional methods.In addition,HQNN-SFOP has good migration generalization ability on five commercial drones and random drones data at different SNR conditions.Our method verifies the feasibility and effectiveness of signal detection methods based on quantum computation and experimentally demonstrates that the advantages of quantum computation for information processing are still valid in the field of signal processing,it provides a highly efficient method for the drone detection using radar return signals.展开更多
The characteristics of the nonlinear dynamics in the Heavy Ion Collision (HIC) at intermediate energies have been studied by evaluating the productions of the Generalized Entropy (GE) and the Multifragmentation Entrop...The characteristics of the nonlinear dynamics in the Heavy Ion Collision (HIC) at intermediate energies have been studied by evaluating the productions of the Generalized Entropy (GE) and the Multifragmentation Entropy (ME) as well as the features of the information and fractal dimensions within the Isospin Quantum Molecular Dynamical Model compensated by the lattice methods. Results demonstrate from various views that the existence of deterministic chaos in the dynamical process of reaction.展开更多
In this work, we study existence theorem of the initial value problem for the system of fractional differential equations where Dα denotes standard Riemann-Liouville fractional derivative, 0 and A ?is a square matrix...In this work, we study existence theorem of the initial value problem for the system of fractional differential equations where Dα denotes standard Riemann-Liouville fractional derivative, 0 and A ?is a square matrix. At the same time, power-type estimate for them has been given.展开更多
Dispersal is an important area of ecological and evolutionary research.Although many studies have been conducted in mammals and birds,dispersal pattern in amphibians is still unclear.To verify dispersal patterns of am...Dispersal is an important area of ecological and evolutionary research.Although many studies have been conducted in mammals and birds,dispersal pattern in amphibians is still unclear.To verify dispersal patterns of amphibians,an endangered species the Emei Moustache Toad(Leptobrachium boringii)was selected.In this study,we analyzed six genetic parameters:inbreeding coefficient(F_(IS)),gene diversity(H_S),the mean of corrected assignment index(mAI_C),the variance of corrected assignment index(vAI_C),relatedness(r)for all three years together and each year separately based on eight highly polymorphic microsatellite loci.Data in totaled across years and each year for 581 individuals captured during 2013–2015 revealed a significant female-biased dispersal pattern.Significantly higher F_(IS) and H_S in females,and lower mAI_C and r for each year separately in females support that L.boringii displays femalebiased dispersal,although r for the total dataset and vAI_C tests did not show significant differences between the sexes.Female-biased dispersal patterns may be explained by the local resource competition hypothesis.展开更多
Attendance patterns are a key factor affecting sexual selection and mating systems in lekbreeding species.However,there are few systematic studies on attendance patterns in lek-breeding anurans.In this study,we monito...Attendance patterns are a key factor affecting sexual selection and mating systems in lekbreeding species.However,there are few systematic studies on attendance patterns in lek-breeding anurans.In this study,we monitored a population of Omei treefrogs(Rhacophorus omeimontis) for four consecutive years to reveal in detail the effects of attendance patterns on mating systems.We found that(1) female nightly attendance was affected by male nightly attendance,and operational sex ratios(determined by male and female nightly attendance) ultimately determined the extent of female polyandry;(2) males surviving more than one breeding season maintained high chorus attendance and mating success,suggesting that male chorus attendance is a good predictor of male genetic quality;(3) the distributions of male mating success were not significantly different from a Poisson distribution,indicating a random mating pattern;and male mating success was not related to body size(size-assortative mating was not evident) but was significantly correlated with chorus attendance.Since the chorus attendance is a predictor of male genetic quality,females performing random mating were more likely to mate with more frequently present males and could therefore gain indirect benefits from mating with higher-than-average quality males,thereby producing good offspring without incurring the significant costs involved in prolonged searching for,and assessing males.Our systematic survey on the relationship between attendance patterns and the lek mating system in R.omeimontis could help us better understand in-depth anuran lek mating systems.展开更多
Aroma is an important quality parameter for breeding in rice(Oryza sativa).For example,the aromatic rice varieties basmati and jasmine rice,with a popcorn-like scent,are popular worldwide and routinely command a price...Aroma is an important quality parameter for breeding in rice(Oryza sativa).For example,the aromatic rice varieties basmati and jasmine rice,with a popcorn-like scent,are popular worldwide and routinely command a price premium.2-acetyl-1-pyrroline(2AP)is a key flavor compound among over 200 volatiles identified in fragrant rice.A naturally fragrant germplasm exists in multiple plant species besides rice,which all exhibit lower activity of BETAINE ALDEHYDE DEHYDROGENASE 2(BADH2).However,no equivalent aromatic germplasm has been described in maize(Zea mays).Here,we characterized the two maize BADH2 homologs,ZmBADH2a and ZmBADH2b.We generated zmbadh2a and zmbadh2b single mutants and the zmbadh2a-zmbadh2b double mutant by CRISPR/Cas in four inbred lines.A popcorn-like scent was only noticeable in seeds from the double mutant,but not from either single mutant or in wild type.In agreement,we only detected 2AP in fresh kernels and dried mature seeds from the double mutant,which accumulated between 0.028 and 0.723 mg/kg 2AP.These results suggest that ZmBADH2a and ZmBADH2b redundantly participate in 2AP biosynthesis in maize,and represent the creation of the world's first aromatic maize by simultaneous genome editing of the two BADH2 genes.展开更多
Rational design and synthesis of highly efficient and robust photocatalysts with positive exciton splitting and interfacial charge transfer for environmental applications is critical.Herein,aiming at overcoming the co...Rational design and synthesis of highly efficient and robust photocatalysts with positive exciton splitting and interfacial charge transfer for environmental applications is critical.Herein,aiming at overcoming the common shortcomings of traditional photocatalysts such as weak photoresponsivity,rapid combination of photo-generated carriers and unstable structure,a novel Ag-bridged dual Z-scheme g-C_(3)N_(4)/BiOI/AgI plasmonic heterojunction was successfully synthesized using a facile method.Results showed that Ag-AgI nanoparticles and three-dimensional(3D)BiOI microspheres were decorated highly uniformly on the 3D porous g-C_(3)N_(4) nanosheet,resulting in a higher specific surface area and abundant active sites.The optimized 3D porous dual Z-scheme g-C_(3)N_(4)/BiOI/Ag-AgI manifested exceptional photocatalytic degradation efficiency of tetracycline(TC)in water with approximately 91.8%degradation efficiency within 165 min,outperforming majority of the reported g-C_(3)N_(4)-based photocatalysts.Moreover,g-C_(3)N_(4)/BiOI/Ag-AgI exhibited good stability in terms of activity and structure.In-depth radical scavenging and electron paramagnetic resonance(EPR)analyses confirmed the relative contributions of various scavengers.Mechanism analysis indicated that the improved photocatalytic performance and stability were ascribed to the highly ordered 3D porous framework,fast electron transfer of dual Z-scheme heterojunction,desirable photocatalytic performance of BiOI/AgI and synergistic effect of Ag plasmas.Therefore,the 3D porous Z-scheme g-C_(3)N_(4)/BiOI/Ag-AgI heterojunction had a good prospect for applications in water remediation.The current work provides new insight and useful guidance for designing novel structural photocatalysts for environment-related applications.展开更多
Nb-doped ZnO thin films were fabricated on glass substrates by using co-sputtering with direct-current and radio frequency magnetron sputtering.The structures,optical and electrical performances of Nb-doped ZnO thin f...Nb-doped ZnO thin films were fabricated on glass substrates by using co-sputtering with direct-current and radio frequency magnetron sputtering.The structures,optical and electrical performances of Nb-doped ZnO thin films were investigated.The results showed that all thin films have(002)c-axis preferential orientation.The minimum resistivity of 2.12×10^(-3)Ωcm and the maximum carrier concentration of 2.39×10^(19 )cm^(-3) were obtained at the direct-current sputtering power of 10W,respectively.Nb-doped ZnO thin films have also shown high average transmittance of 89.6%,and lower surface roughness of 2.74 nm.Meanwhile,a distinct absorption edge in the ultraviolet range of 300–400 nm was observed in absorbance,the optical band gap of Nb-doped ZnO thin films illustrates an increased tendency with increasing Nb concentration.展开更多
基金supported by Major Science and Technology Projects in Henan Province,China,Grant No.221100210600.
文摘With the wide application of drone technology,there is an increasing demand for the detection of radar return signals from drones.Existing detection methods mainly rely on time-frequency domain feature extraction and classical machine learning algorithms for image recognition.This method suffers from the problem of large dimensionality of image features,which leads to large input data size and noise affecting learning.Therefore,this paper proposes to extract signal time-domain statistical features for radar return signals from drones and reduce the feature dimension from 512×4 to 16 dimensions.However,the downscaled feature data makes the accuracy of traditional machine learning algorithms decrease,so we propose a new hybrid quantum neural network with signal feature overlay projection(HQNN-SFOP),which reduces the dimensionality of the signal by extracting the statistical features in the time domain of the signal,introduces the signal feature overlay projection to enhance the expression ability of quantum computation on the signal features,and introduces the quantum circuits to improve the neural network’s ability to obtain the inline relationship of features,thus improving the accuracy and migration generalization ability of drone detection.In order to validate the effectiveness of the proposed method,we experimented with the method using the MM model that combines the real parameters of five commercial drones and random drones parameters to generate data to simulate a realistic environment.The results show that the method based on statistical features in the time domain of the signal is able to extract features at smaller scales and obtain higher accuracy on a dataset with an SNR of 10 dB.On the time-domain feature data set,HQNNSFOP obtains the highest accuracy compared to other conventional methods.In addition,HQNN-SFOP has good migration generalization ability on five commercial drones and random drones data at different SNR conditions.Our method verifies the feasibility and effectiveness of signal detection methods based on quantum computation and experimentally demonstrates that the advantages of quantum computation for information processing are still valid in the field of signal processing,it provides a highly efficient method for the drone detection using radar return signals.
文摘The characteristics of the nonlinear dynamics in the Heavy Ion Collision (HIC) at intermediate energies have been studied by evaluating the productions of the Generalized Entropy (GE) and the Multifragmentation Entropy (ME) as well as the features of the information and fractal dimensions within the Isospin Quantum Molecular Dynamical Model compensated by the lattice methods. Results demonstrate from various views that the existence of deterministic chaos in the dynamical process of reaction.
文摘In this work, we study existence theorem of the initial value problem for the system of fractional differential equations where Dα denotes standard Riemann-Liouville fractional derivative, 0 and A ?is a square matrix. At the same time, power-type estimate for them has been given.
基金financially supported by the National Natural Science Foundation of China (No.31770405)
文摘Dispersal is an important area of ecological and evolutionary research.Although many studies have been conducted in mammals and birds,dispersal pattern in amphibians is still unclear.To verify dispersal patterns of amphibians,an endangered species the Emei Moustache Toad(Leptobrachium boringii)was selected.In this study,we analyzed six genetic parameters:inbreeding coefficient(F_(IS)),gene diversity(H_S),the mean of corrected assignment index(mAI_C),the variance of corrected assignment index(vAI_C),relatedness(r)for all three years together and each year separately based on eight highly polymorphic microsatellite loci.Data in totaled across years and each year for 581 individuals captured during 2013–2015 revealed a significant female-biased dispersal pattern.Significantly higher F_(IS) and H_S in females,and lower mAI_C and r for each year separately in females support that L.boringii displays femalebiased dispersal,although r for the total dataset and vAI_C tests did not show significant differences between the sexes.Female-biased dispersal patterns may be explained by the local resource competition hypothesis.
基金supported by the National Natural Science Foundation of China(No.31470442)。
文摘Attendance patterns are a key factor affecting sexual selection and mating systems in lekbreeding species.However,there are few systematic studies on attendance patterns in lek-breeding anurans.In this study,we monitored a population of Omei treefrogs(Rhacophorus omeimontis) for four consecutive years to reveal in detail the effects of attendance patterns on mating systems.We found that(1) female nightly attendance was affected by male nightly attendance,and operational sex ratios(determined by male and female nightly attendance) ultimately determined the extent of female polyandry;(2) males surviving more than one breeding season maintained high chorus attendance and mating success,suggesting that male chorus attendance is a good predictor of male genetic quality;(3) the distributions of male mating success were not significantly different from a Poisson distribution,indicating a random mating pattern;and male mating success was not related to body size(size-assortative mating was not evident) but was significantly correlated with chorus attendance.Since the chorus attendance is a predictor of male genetic quality,females performing random mating were more likely to mate with more frequently present males and could therefore gain indirect benefits from mating with higher-than-average quality males,thereby producing good offspring without incurring the significant costs involved in prolonged searching for,and assessing males.Our systematic survey on the relationship between attendance patterns and the lek mating system in R.omeimontis could help us better understand in-depth anuran lek mating systems.
文摘Aroma is an important quality parameter for breeding in rice(Oryza sativa).For example,the aromatic rice varieties basmati and jasmine rice,with a popcorn-like scent,are popular worldwide and routinely command a price premium.2-acetyl-1-pyrroline(2AP)is a key flavor compound among over 200 volatiles identified in fragrant rice.A naturally fragrant germplasm exists in multiple plant species besides rice,which all exhibit lower activity of BETAINE ALDEHYDE DEHYDROGENASE 2(BADH2).However,no equivalent aromatic germplasm has been described in maize(Zea mays).Here,we characterized the two maize BADH2 homologs,ZmBADH2a and ZmBADH2b.We generated zmbadh2a and zmbadh2b single mutants and the zmbadh2a-zmbadh2b double mutant by CRISPR/Cas in four inbred lines.A popcorn-like scent was only noticeable in seeds from the double mutant,but not from either single mutant or in wild type.In agreement,we only detected 2AP in fresh kernels and dried mature seeds from the double mutant,which accumulated between 0.028 and 0.723 mg/kg 2AP.These results suggest that ZmBADH2a and ZmBADH2b redundantly participate in 2AP biosynthesis in maize,and represent the creation of the world's first aromatic maize by simultaneous genome editing of the two BADH2 genes.
基金supported by the National Natural Science Foundation of China(Nos.22106020 and 42122056)the KeyArea Research and Development Program of Guangdong Province(No.2020B1111350002)+1 种基金the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Z032)the Guangdong Basic and Applied Basic Research Foundation(No.2020A1515110718).
文摘Rational design and synthesis of highly efficient and robust photocatalysts with positive exciton splitting and interfacial charge transfer for environmental applications is critical.Herein,aiming at overcoming the common shortcomings of traditional photocatalysts such as weak photoresponsivity,rapid combination of photo-generated carriers and unstable structure,a novel Ag-bridged dual Z-scheme g-C_(3)N_(4)/BiOI/AgI plasmonic heterojunction was successfully synthesized using a facile method.Results showed that Ag-AgI nanoparticles and three-dimensional(3D)BiOI microspheres were decorated highly uniformly on the 3D porous g-C_(3)N_(4) nanosheet,resulting in a higher specific surface area and abundant active sites.The optimized 3D porous dual Z-scheme g-C_(3)N_(4)/BiOI/Ag-AgI manifested exceptional photocatalytic degradation efficiency of tetracycline(TC)in water with approximately 91.8%degradation efficiency within 165 min,outperforming majority of the reported g-C_(3)N_(4)-based photocatalysts.Moreover,g-C_(3)N_(4)/BiOI/Ag-AgI exhibited good stability in terms of activity and structure.In-depth radical scavenging and electron paramagnetic resonance(EPR)analyses confirmed the relative contributions of various scavengers.Mechanism analysis indicated that the improved photocatalytic performance and stability were ascribed to the highly ordered 3D porous framework,fast electron transfer of dual Z-scheme heterojunction,desirable photocatalytic performance of BiOI/AgI and synergistic effect of Ag plasmas.Therefore,the 3D porous Z-scheme g-C_(3)N_(4)/BiOI/Ag-AgI heterojunction had a good prospect for applications in water remediation.The current work provides new insight and useful guidance for designing novel structural photocatalysts for environment-related applications.
文摘Nb-doped ZnO thin films were fabricated on glass substrates by using co-sputtering with direct-current and radio frequency magnetron sputtering.The structures,optical and electrical performances of Nb-doped ZnO thin films were investigated.The results showed that all thin films have(002)c-axis preferential orientation.The minimum resistivity of 2.12×10^(-3)Ωcm and the maximum carrier concentration of 2.39×10^(19 )cm^(-3) were obtained at the direct-current sputtering power of 10W,respectively.Nb-doped ZnO thin films have also shown high average transmittance of 89.6%,and lower surface roughness of 2.74 nm.Meanwhile,a distinct absorption edge in the ultraviolet range of 300–400 nm was observed in absorbance,the optical band gap of Nb-doped ZnO thin films illustrates an increased tendency with increasing Nb concentration.