Warhead power assessment of the anti-ship missile plays a vital role in determining the optimal design of missile, thus having important strategic research significance. However, in the assessment process, expert’s j...Warhead power assessment of the anti-ship missile plays a vital role in determining the optimal design of missile, thus having important strategic research significance. However, in the assessment process, expert’s judgement will directly affect the assessment accuracy. In addition,there are many criteria involved in the missile design alternatives. Some criteria with poor performance may be compensated by other criteria with excellent performance, and then it is impossible to find the truly optimal alternative. Aimed at solving these problems, this paper proposes a synthetical assessment process based on fuzzy hesitant linguistic term set and the Gained and Lost Dominance Score(GLDS) method. In order to improve the assessment accuracy of experts and solve the problem that experts generate different opinions, combined with the advantages of fuzzy hesitant sets and linguistic term sets, the double hierarchy hesitant fuzzy linguistic term sets are used in this paper to improve the accuracy of expert’s judgement. In order to effectively combine expert’s experience with the data of criteria, the evidence theory and entropy weight method are used to transfer the expert’s judgement to the weight. In order to avoid selecting defective alternative of missile design, the GLDS is used to fuse expert information and criteria information. Sensitivity analysis shows that the assessment process has sensitivity to some extent. However, when the fluctuation of expert’s assessment makes the fluctuation of θ in the range of-5% to 5%, the impact on the results is not quite conspicuous. The analysis of calculation result and comparative analysis show that the assessment process proposed in this paper is accurate enough, has great advantage in selecting the current and potential optimal alternative of missile design, and avoids the alternatives with low criteria performance that cannot be compensated by other criteria being selected.展开更多
This paper presents the theoretical studies on the propagation of optical pulses in a deviated Gaussian gained Kerr medium.Our numerical results have shown,for the first time,that the compression of optical pulse widt...This paper presents the theoretical studies on the propagation of optical pulses in a deviated Gaussian gained Kerr medium.Our numerical results have shown,for the first time,that the compression of optical pulse widths varies considerably for differently deviated Gaussian gain.展开更多
Checked by Henan Province Development and Relbrm Commission and Henan Province MunicipalFinance （）ffice, the “R ＆ I） and Industrialization of High Performance Functional Refractories for Metallurgy New Technology...Checked by Henan Province Development and Relbrm Commission and Henan Province MunicipalFinance （）ffice, the “R ＆ I） and Industrialization of High Performance Functional Refractories for Metallurgy New Technology” project declared by 1,1RR gained a special fund support on self-renovation and products structure adjustment. The project will realize the technology integration and industriali-zation of key refractories including purging component, metering nozzle and toil and belt continuous casting nozzle, etc. through building high performance functional refractories production lines for metallurgy new technology.展开更多
Recently, State Intellectual Property Office of China authorized an invention patent to a project ＂ Self- flowing Castables for Filling Back Joints of Aluminum Electrolytic Cell Side Wall＂ of Sinosteel Refractory Co...Recently, State Intellectual Property Office of China authorized an invention patent to a project ＂ Self- flowing Castables for Filling Back Joints of Aluminum Electrolytic Cell Side Wall＂ of Sinosteel Refractory Co., Ltd. This patent involves one kind of self-flowing castables for filling the joints between shell and side wall brick of aluminum electrolytic cell. The castables can prolong the service life of aluminum electrolytic cell and side wall brick,展开更多
Currently, ＂ Porous SiC Multi-phase Ceramics with Hierarchical Heterogeneities for Filtrating High Temperature Soot＂ , a project of Sinosteel LIRR, gained International S＆T Cooperation Special Funds from Ministry o...Currently, ＂ Porous SiC Multi-phase Ceramics with Hierarchical Heterogeneities for Filtrating High Temperature Soot＂ , a project of Sinosteel LIRR, gained International S＆T Cooperation Special Funds from Ministry of Science and Technology of China.展开更多
Pien Tze Huang released a notice that the Fujian Pien Tze Huang Cosmetics Co.,Ltd(hereinafter referred to as“Pien Tze Huang cosmetics”)gained the recognition from high-andnew-tech businesses and enjoyed 15%income ta...Pien Tze Huang released a notice that the Fujian Pien Tze Huang Cosmetics Co.,Ltd(hereinafter referred to as“Pien Tze Huang cosmetics”)gained the recognition from high-andnew-tech businesses and enjoyed 15%income tax discount.According to the notice,this was the another recognition upon expiration of validity of the certificate.The company was recognized as high-and-newtech business in 2008 for the first time.展开更多
Wushu,or Chinese martial arts,is set to make its Olympic debut in the Youth Olympic Games 2026 in Dakar,the first Olympic competition to be staged in Africa.Wushu,which featured at the All-Africa Youth Games in 2018,h...Wushu,or Chinese martial arts,is set to make its Olympic debut in the Youth Olympic Games 2026 in Dakar,the first Olympic competition to be staged in Africa.Wushu,which featured at the All-Africa Youth Games in 2018,has gone through a tortuous process in being accepted as an Olympic sport event.The International Wushu Federation(IWUF)first submitted applications for inclusion to the International Olympic Committee in 2001,followed by two more failed bids in 2008 and 2011.Finally,it tasted success in Africa,which is also a testament to its popularity in the continent.展开更多
Quasi-two-dimensional(quasi-2d)perovskites are promising gain media for micro-nano lasers,yet their uncontrolled crystallization and abundant low-n phases often hinder optical gain and device performance.In this work,...Quasi-two-dimensional(quasi-2d)perovskites are promising gain media for micro-nano lasers,yet their uncontrolled crystallization and abundant low-n phases often hinder optical gain and device performance.In this work,we introduce ethyl acetate(EA)as a green antisolvent to fabricate high-quality quasi-2D PEA_(0.4)MAPbBr_(3)films.The EA-treated films exhibit superior morphology,enhanced crystallinity,and notably inhibited low n-phases.These improvements yield a prolonged photoluminescence lifetime of 26.3 ns and a substantially extended gain lifetime of 129 ps.Consequently,the optimized film exhibits a markedly reduced amplified spontaneous emission(ASE)threshold of 5.6μJ·cm^(-2)and a high net modal gain of 935 cm^(-1).Leveraging these enhanced gain properties,we successfully demonstrate a vertical-cavity surface-emitting laser(VCSEL)based on a dielectric Bragg reflector microcavity,which delivers single-mode lasing at 528.3 nm and a high quality factor of~5886.This work presents a green-solvent-engineering strategy for high-performance perovskite lasers,advancing their prospects for scalable photonic integration.展开更多
In this study,with the aim of achieving a high signal-to-noise ratio(SNR)in an electron-bombarded complementary metal-oxide-semiconductor(EBCMOS)imaging chip,we analyzed the sources of noise using principles from low-...In this study,with the aim of achieving a high signal-to-noise ratio(SNR)in an electron-bombarded complementary metal-oxide-semiconductor(EBCMOS)imaging chip,we analyzed the sources of noise using principles from low-light-level imaging and semiconductor theory,and established a physical computational model that relates the electron-multiplication layer to the noise characteristics of an EBCMOS chip in a uniformly doped structure with a P-type substrate.We conducted theoretical calculations to analyze the effects on noise characteristics of the passivation layer material and thickness,P-substrate doping concentration,P-substrate thickness,incident electron energy,and substrate temperature.By comparing the characteristics of pixel noise,dark current,multiplication electron numbers,and SNR under various structures,we simulated optimized structural parameters of the device.Our simulation results showed that the noise characteristics of the device could be optimized using an Al_(2)O_(3)passivation thickness of 15 nm and substrate temperature of 260 K,and by decreasing the doping concentration and thickness of the P-type substrate and increasing the incident electron energy.The optimized SNR were 252 e/e.And the substantial impact of dark current noise,primarily governed by interfacial defects,on the overall noise characteristics of the device.This research offers theoretical support to develop EBCMOS imaging chips with high gain and SNR.展开更多
Root nodule symbiosis(RNS)is a mutualistic association formed between nitrogen-fixing rhizobia or Frankia and host plants limited to four orders within Rosid I―Fabales,Fagales,Cucurbitales,and Rosales―which comprise...Root nodule symbiosis(RNS)is a mutualistic association formed between nitrogen-fixing rhizobia or Frankia and host plants limited to four orders within Rosid I―Fabales,Fagales,Cucurbitales,and Rosales―which comprise the so-called‘Nitrogen Fixing Nodulation Clade’(NFNC).The majority of nodulation studies have focused on Leguminosae,given their agricultural and environmental importance,as well as the widespread occurrence of nodulation among members of this family.Endowing cereal crops with nitrogen fixation,like Leguminosae,presents a strategy to reduce the detrimental effects of synthetic fertilizer overuse.Different hypotheses on the origin of RNS have been proposed;however,key genetic innovations underlying the evolution of RNS,even in Leguminosae,have been rarely reported.In this review,we begin by examining current knowledge of genetic innovations―including gene gain,gene loss,and the acquisition or loss of conserved noncoding sequences(CNS)in preexisting genes.We explore the available evidence supporting these genetic innovations underlying the evolution of RNS in Leguminosae and offer the phylogenomics approach that could be applied to uncover these genetic innovations.Finally,we conclude by proposing a model of genetic innovations underlying the evolution of RNS in Leguminosae and consider the potential implications for the development of nitrogen-fixing crops.展开更多
Integrated sensing and communication(ISAC)is an appealing approach to address spectrum congestion and beamforming is an effective method to realize ISAC.In this paper,we investigate the beamforming design problem for ...Integrated sensing and communication(ISAC)is an appealing approach to address spectrum congestion and beamforming is an effective method to realize ISAC.In this paper,we investigate the beamforming design problem for multiple-input multipleoutput(MIMO)ISAC systems and propose to maximize the radar beampattern gain of the target direction while ensuring the signal-to-interference-plus-noise ratio(SINR)constraints of communication users.Particularly,we discuss two cases of ISAC transmit beamforming,i.e.,Case-Ⅰand Case-Ⅱ,which do not have and do have the dedicated probing signal,respectively.For these two cases of transmit beamforming design problems,we start from the single-user scenario and provide the closed-form solutions for MIMO ISAC beamforming vectors.Then,we consider the multiuser scenario and utilize the semidefinite relaxation technique to convert the beamforming design problems into convex semidefinite programming problems.Furthermore,we investigate the impact of the channel correlation between radar and communication on the performance gain of MIMO ISAC systems and characterize the performance tradeoff.Numerical results validate that the dedicated probing signal is unnecessary in the single-user scenario,whereas it has a slight improvement in target detection performance at low SINR thresholds in the multi-user scenario.It is also shown that the stronger the correlation between radar and communication channels,the greater the performance gain of the system.展开更多
Integrated sensing and communication(ISAC) systems can enhance security and reliability in full-duplex( FD) networks.This paper studies the resource allocation problem in FD networks based on ISAC.We formulate an opti...Integrated sensing and communication(ISAC) systems can enhance security and reliability in full-duplex( FD) networks.This paper studies the resource allocation problem in FD networks based on ISAC.We formulate an optimization problem that jointly considers beamforming,radar waveform,and reflection coefficient of a hybrid reconfigurable intelligent surface,aiming to maximize the beampattern gain of the concealed target while maintaining the quality of service of communication users.A two-stage algorithm is designed to solve this problem: the first stage optimizes the radar waveform and beamforming,and the second focuses on the reflection coefficient design.We acquire the feasible solution using semidefinite programming relaxation.The optimality of the feasible solution for radar waveform and beamforming subproblem is ensured through Cauchy-Schwartz inequality.For the reflection coefficient design,an approximate optimal solution is acquired through successive convex approximation.Numerical results demonstrate that the proposed algorithm can achieve a superior performance trade-off between communication and radar sensing compared to the benchmarks.展开更多
Investigated theoretically is a photonic-crystal surface-emitting GaN laser based on surface-etched holes with a porous-GaN cladding layer.The porous GaN has a low refractive index,supporting effective confinement to ...Investigated theoretically is a photonic-crystal surface-emitting GaN laser based on surface-etched holes with a porous-GaN cladding layer.The porous GaN has a low refractive index,supporting effective confinement to the resonant mode,and the porous GaN is derived from as-grown GaN,eliminating the lattice mismatch issues typically associated with GaN platforms.Studied systematically is how the photoniccrystal lattice constant,air hole radius,etching depth,and porous-GaN refractive index affect the performance of the laser.The results show that the laser exhibits optimal overall performance when the lattice constant is 216 nm and the hole radius is 60 nm.The etching depth can be chosen between 30 and 100 nm,and the porous-GaN refractive index is preferably in the range of 1.7–1.9.The research achieves a quality factor as high as 1.9×10^(4),with a photonic-crystal-layer confinement factor of 4.24%and an active-layer confinement factor of 21.8%,along with a low threshold gain of 77 cm^(−1).展开更多
We introduce a minimal model consisting of a two-body system with stochastically broken reciprocity(i.e.random violation of Newton's third law)and then investigate its statistical behaviors,including fluctuations ...We introduce a minimal model consisting of a two-body system with stochastically broken reciprocity(i.e.random violation of Newton's third law)and then investigate its statistical behaviors,including fluctuations of velocity and position,time evolution of probability distribution functions,energy gain,and entropy production.The effective temperature of this two-body system immersed in a thermal bath is also derived.Furthermore,we heuristically present an extremely minimal model where the relative motion adheres to the same rules as in classical mechanics,while the effect of stochastically broken reciprocity only manifests in the fluctuating motion of the center of mass.展开更多
Rydberg-atom-based superheterodyne receivers integrate self-calibration,high sensitivity,a wide operational frequency range,and phase/frequency resolved detection capabilities,demonstrating broad application prospects...Rydberg-atom-based superheterodyne receivers integrate self-calibration,high sensitivity,a wide operational frequency range,and phase/frequency resolved detection capabilities,demonstrating broad application prospects as nextgeneration microwave receivers.Linear gain and linear dynamic range(LDR)are critical metrics for assessing receiver sensitivity and demodulation fidelity,respectively.We numerically solve the four-level master equation and then employ particle swarm optimization(PSO)algorithm to co-optimize linear gain and LDR in atomic superheterodyne receivers based on balanced homodyne detection.Further,we systematically account for dominant dephasing mechanisms in the simulation,encompassing spontaneous decay,transit dephasing,collision dephasing,laser linewidth dephasing,and Doppler averaging.Homodyne readout utilizes both the real and imaginary parts of polarizability for sensing.In the case of the photon shot noise limit,its signal-to-noise ratio(SNR)expression resembles that of direct optical-intensity readout.However,the inherent coherent subtraction operation in homodyne detection significantly suppresses common-mode noise,while appropriately increasing the reference beam power enhances the gain in practical experiments.Indeed,this co-optimization problem,characterized by a high-dimensional variable space,two objectives,and non-convexity,is well-suited for solution by PSO.In addition,probe and coupling detuning contribute equivalently to polarizability and compensate for each other owing to Doppler averaging,thereby reducing the optimization variable space by one.By adopting a product form of linear gain and LDR as the fitness function,the PSO achieves rapid convergence.Here,the effectiveness of the PSO results is verified via the total harmonic distortion(THD).The relative error-based LDR calculation method we proposed efficiently measures receiver response linearity with consuming fewer computational resources.This research is expected to offer valuable insights into enhancing the performance of Rydberg-atom-based superheterodyne receivers.展开更多
In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved cerami...In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures.展开更多
Integration of renewable energy sources into power systems requires efficient multilevel inverters,capable of producing high-quality output voltage with low total harmonic distortion(THD).Conventional multilevel inver...Integration of renewable energy sources into power systems requires efficient multilevel inverters,capable of producing high-quality output voltage with low total harmonic distortion(THD).Conventional multilevel inverters often suffer from high component count,high switching stress,low voltage gain,and increased cost,limiting their practical application.This paper introduces a high-gain novel topology for multilevel inverters with reduced number of total components per level count,low voltage stress on power conductive devices,and minimizing a cost function,which depends on the number of components,standing voltage on switches and diodes,output voltage levels,and gain.The designed topology,which can be applied in photovoltaic(PV)systems,utilizes only one direct current(DC)input supply and a modular structure with the ability of capacitor’s voltage self-balancing.The high gain property and low THD of the proposed topology are two advantages that provide sine output waveform,with no need to a high DC input voltage source.Moreover,generalized topology,consisting of cascaded basic units,has been proposed.A comprehensive method has been proposed to determining the values of DC supplies in this configuration,aiming to minimize redundant switching modes and maximize the voltage levels count.The comparison with some other multilevel inverters confirms the desired performance of the basic version given inverter.A prototype has been also implemented and the experimental results have been obtained to verify the advantages of the proposed 25-level topology.展开更多
Since the launch of island-wide special customs operations at Hainan Free Trade Port(Hainan FTP),the proportion of “zero-tariff”imported goods has increased significantly from 21 to 74 percent, and high-quality good...Since the launch of island-wide special customs operations at Hainan Free Trade Port(Hainan FTP),the proportion of “zero-tariff”imported goods has increased significantly from 21 to 74 percent, and high-quality goods from Southeast Asia can enter Hainan at a more competitive price. If goods contain imported materials and achieve at least 30 percent added value through local processing,they can enter the Chinese mainland market with an exemption from import tariffs, effectively gaining market access across China.展开更多
文摘Warhead power assessment of the anti-ship missile plays a vital role in determining the optimal design of missile, thus having important strategic research significance. However, in the assessment process, expert’s judgement will directly affect the assessment accuracy. In addition,there are many criteria involved in the missile design alternatives. Some criteria with poor performance may be compensated by other criteria with excellent performance, and then it is impossible to find the truly optimal alternative. Aimed at solving these problems, this paper proposes a synthetical assessment process based on fuzzy hesitant linguistic term set and the Gained and Lost Dominance Score(GLDS) method. In order to improve the assessment accuracy of experts and solve the problem that experts generate different opinions, combined with the advantages of fuzzy hesitant sets and linguistic term sets, the double hierarchy hesitant fuzzy linguistic term sets are used in this paper to improve the accuracy of expert’s judgement. In order to effectively combine expert’s experience with the data of criteria, the evidence theory and entropy weight method are used to transfer the expert’s judgement to the weight. In order to avoid selecting defective alternative of missile design, the GLDS is used to fuse expert information and criteria information. Sensitivity analysis shows that the assessment process has sensitivity to some extent. However, when the fluctuation of expert’s assessment makes the fluctuation of θ in the range of-5% to 5%, the impact on the results is not quite conspicuous. The analysis of calculation result and comparative analysis show that the assessment process proposed in this paper is accurate enough, has great advantage in selecting the current and potential optimal alternative of missile design, and avoids the alternatives with low criteria performance that cannot be compensated by other criteria being selected.
文摘This paper presents the theoretical studies on the propagation of optical pulses in a deviated Gaussian gained Kerr medium.Our numerical results have shown,for the first time,that the compression of optical pulse widths varies considerably for differently deviated Gaussian gain.
文摘Checked by Henan Province Development and Relbrm Commission and Henan Province MunicipalFinance （）ffice, the “R ＆ I） and Industrialization of High Performance Functional Refractories for Metallurgy New Technology” project declared by 1,1RR gained a special fund support on self-renovation and products structure adjustment. The project will realize the technology integration and industriali-zation of key refractories including purging component, metering nozzle and toil and belt continuous casting nozzle, etc. through building high performance functional refractories production lines for metallurgy new technology.
文摘Recently, State Intellectual Property Office of China authorized an invention patent to a project ＂ Self- flowing Castables for Filling Back Joints of Aluminum Electrolytic Cell Side Wall＂ of Sinosteel Refractory Co., Ltd. This patent involves one kind of self-flowing castables for filling the joints between shell and side wall brick of aluminum electrolytic cell. The castables can prolong the service life of aluminum electrolytic cell and side wall brick,
文摘Currently, ＂ Porous SiC Multi-phase Ceramics with Hierarchical Heterogeneities for Filtrating High Temperature Soot＂ , a project of Sinosteel LIRR, gained International S＆T Cooperation Special Funds from Ministry of Science and Technology of China.
文摘Pien Tze Huang released a notice that the Fujian Pien Tze Huang Cosmetics Co.,Ltd(hereinafter referred to as“Pien Tze Huang cosmetics”)gained the recognition from high-andnew-tech businesses and enjoyed 15%income tax discount.According to the notice,this was the another recognition upon expiration of validity of the certificate.The company was recognized as high-and-newtech business in 2008 for the first time.
文摘Wushu,or Chinese martial arts,is set to make its Olympic debut in the Youth Olympic Games 2026 in Dakar,the first Olympic competition to be staged in Africa.Wushu,which featured at the All-Africa Youth Games in 2018,has gone through a tortuous process in being accepted as an Olympic sport event.The International Wushu Federation(IWUF)first submitted applications for inclusion to the International Olympic Committee in 2001,followed by two more failed bids in 2008 and 2011.Finally,it tasted success in Africa,which is also a testament to its popularity in the continent.
文摘Quasi-two-dimensional(quasi-2d)perovskites are promising gain media for micro-nano lasers,yet their uncontrolled crystallization and abundant low-n phases often hinder optical gain and device performance.In this work,we introduce ethyl acetate(EA)as a green antisolvent to fabricate high-quality quasi-2D PEA_(0.4)MAPbBr_(3)films.The EA-treated films exhibit superior morphology,enhanced crystallinity,and notably inhibited low n-phases.These improvements yield a prolonged photoluminescence lifetime of 26.3 ns and a substantially extended gain lifetime of 129 ps.Consequently,the optimized film exhibits a markedly reduced amplified spontaneous emission(ASE)threshold of 5.6μJ·cm^(-2)and a high net modal gain of 935 cm^(-1).Leveraging these enhanced gain properties,we successfully demonstrate a vertical-cavity surface-emitting laser(VCSEL)based on a dielectric Bragg reflector microcavity,which delivers single-mode lasing at 528.3 nm and a high quality factor of~5886.This work presents a green-solvent-engineering strategy for high-performance perovskite lasers,advancing their prospects for scalable photonic integration.
文摘In this study,with the aim of achieving a high signal-to-noise ratio(SNR)in an electron-bombarded complementary metal-oxide-semiconductor(EBCMOS)imaging chip,we analyzed the sources of noise using principles from low-light-level imaging and semiconductor theory,and established a physical computational model that relates the electron-multiplication layer to the noise characteristics of an EBCMOS chip in a uniformly doped structure with a P-type substrate.We conducted theoretical calculations to analyze the effects on noise characteristics of the passivation layer material and thickness,P-substrate doping concentration,P-substrate thickness,incident electron energy,and substrate temperature.By comparing the characteristics of pixel noise,dark current,multiplication electron numbers,and SNR under various structures,we simulated optimized structural parameters of the device.Our simulation results showed that the noise characteristics of the device could be optimized using an Al_(2)O_(3)passivation thickness of 15 nm and substrate temperature of 260 K,and by decreasing the doping concentration and thickness of the P-type substrate and increasing the incident electron energy.The optimized SNR were 252 e/e.And the substantial impact of dark current noise,primarily governed by interfacial defects,on the overall noise characteristics of the device.This research offers theoretical support to develop EBCMOS imaging chips with high gain and SNR.
基金supported by the National Natural Science Foundation of China(32300512)and the Xplorer Prize.
文摘Root nodule symbiosis(RNS)is a mutualistic association formed between nitrogen-fixing rhizobia or Frankia and host plants limited to four orders within Rosid I―Fabales,Fagales,Cucurbitales,and Rosales―which comprise the so-called‘Nitrogen Fixing Nodulation Clade’(NFNC).The majority of nodulation studies have focused on Leguminosae,given their agricultural and environmental importance,as well as the widespread occurrence of nodulation among members of this family.Endowing cereal crops with nitrogen fixation,like Leguminosae,presents a strategy to reduce the detrimental effects of synthetic fertilizer overuse.Different hypotheses on the origin of RNS have been proposed;however,key genetic innovations underlying the evolution of RNS,even in Leguminosae,have been rarely reported.In this review,we begin by examining current knowledge of genetic innovations―including gene gain,gene loss,and the acquisition or loss of conserved noncoding sequences(CNS)in preexisting genes.We explore the available evidence supporting these genetic innovations underlying the evolution of RNS in Leguminosae and offer the phylogenomics approach that could be applied to uncover these genetic innovations.Finally,we conclude by proposing a model of genetic innovations underlying the evolution of RNS in Leguminosae and consider the potential implications for the development of nitrogen-fixing crops.
基金National Natural Science Foundation of China under Grant 62571248 and Grant 62201266Key Laboratory of Intelligent Space TTC&O(Space Engineering University),Ministry of Education under Grant CYK2025-01-12。
文摘Integrated sensing and communication(ISAC)is an appealing approach to address spectrum congestion and beamforming is an effective method to realize ISAC.In this paper,we investigate the beamforming design problem for multiple-input multipleoutput(MIMO)ISAC systems and propose to maximize the radar beampattern gain of the target direction while ensuring the signal-to-interference-plus-noise ratio(SINR)constraints of communication users.Particularly,we discuss two cases of ISAC transmit beamforming,i.e.,Case-Ⅰand Case-Ⅱ,which do not have and do have the dedicated probing signal,respectively.For these two cases of transmit beamforming design problems,we start from the single-user scenario and provide the closed-form solutions for MIMO ISAC beamforming vectors.Then,we consider the multiuser scenario and utilize the semidefinite relaxation technique to convert the beamforming design problems into convex semidefinite programming problems.Furthermore,we investigate the impact of the channel correlation between radar and communication on the performance gain of MIMO ISAC systems and characterize the performance tradeoff.Numerical results validate that the dedicated probing signal is unnecessary in the single-user scenario,whereas it has a slight improvement in target detection performance at low SINR thresholds in the multi-user scenario.It is also shown that the stronger the correlation between radar and communication channels,the greater the performance gain of the system.
基金Supported by the National Science and Technology Major Project of China (No.C6-3416-M01)。
文摘Integrated sensing and communication(ISAC) systems can enhance security and reliability in full-duplex( FD) networks.This paper studies the resource allocation problem in FD networks based on ISAC.We formulate an optimization problem that jointly considers beamforming,radar waveform,and reflection coefficient of a hybrid reconfigurable intelligent surface,aiming to maximize the beampattern gain of the concealed target while maintaining the quality of service of communication users.A two-stage algorithm is designed to solve this problem: the first stage optimizes the radar waveform and beamforming,and the second focuses on the reflection coefficient design.We acquire the feasible solution using semidefinite programming relaxation.The optimality of the feasible solution for radar waveform and beamforming subproblem is ensured through Cauchy-Schwartz inequality.For the reflection coefficient design,an approximate optimal solution is acquired through successive convex approximation.Numerical results demonstrate that the proposed algorithm can achieve a superior performance trade-off between communication and radar sensing compared to the benchmarks.
基金funded by the Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant No.NY224125)the Open Fund of the State Key Laboratory of Advanced Optical Communication Systems and Networks(SJTU)(Grant No.2023GZKF018)the Postgraduate Research and Practice Innovation Program of Jiangsu Province(Grant Nos.KYCX24_1199 and SJCX24_0286).
文摘Investigated theoretically is a photonic-crystal surface-emitting GaN laser based on surface-etched holes with a porous-GaN cladding layer.The porous GaN has a low refractive index,supporting effective confinement to the resonant mode,and the porous GaN is derived from as-grown GaN,eliminating the lattice mismatch issues typically associated with GaN platforms.Studied systematically is how the photoniccrystal lattice constant,air hole radius,etching depth,and porous-GaN refractive index affect the performance of the laser.The results show that the laser exhibits optimal overall performance when the lattice constant is 216 nm and the hole radius is 60 nm.The etching depth can be chosen between 30 and 100 nm,and the porous-GaN refractive index is preferably in the range of 1.7–1.9.The research achieves a quality factor as high as 1.9×10^(4),with a photonic-crystal-layer confinement factor of 4.24%and an active-layer confinement factor of 21.8%,along with a low threshold gain of 77 cm^(−1).
基金supported by the National Natural Science Foundation of China(Grant No.12475032)。
文摘We introduce a minimal model consisting of a two-body system with stochastically broken reciprocity(i.e.random violation of Newton's third law)and then investigate its statistical behaviors,including fluctuations of velocity and position,time evolution of probability distribution functions,energy gain,and entropy production.The effective temperature of this two-body system immersed in a thermal bath is also derived.Furthermore,we heuristically present an extremely minimal model where the relative motion adheres to the same rules as in classical mechanics,while the effect of stochastically broken reciprocity only manifests in the fluctuating motion of the center of mass.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.62331024 and 62571549)the National Key Research and Development Program of China(Grant No.2022YFB2802804)。
文摘Rydberg-atom-based superheterodyne receivers integrate self-calibration,high sensitivity,a wide operational frequency range,and phase/frequency resolved detection capabilities,demonstrating broad application prospects as nextgeneration microwave receivers.Linear gain and linear dynamic range(LDR)are critical metrics for assessing receiver sensitivity and demodulation fidelity,respectively.We numerically solve the four-level master equation and then employ particle swarm optimization(PSO)algorithm to co-optimize linear gain and LDR in atomic superheterodyne receivers based on balanced homodyne detection.Further,we systematically account for dominant dephasing mechanisms in the simulation,encompassing spontaneous decay,transit dephasing,collision dephasing,laser linewidth dephasing,and Doppler averaging.Homodyne readout utilizes both the real and imaginary parts of polarizability for sensing.In the case of the photon shot noise limit,its signal-to-noise ratio(SNR)expression resembles that of direct optical-intensity readout.However,the inherent coherent subtraction operation in homodyne detection significantly suppresses common-mode noise,while appropriately increasing the reference beam power enhances the gain in practical experiments.Indeed,this co-optimization problem,characterized by a high-dimensional variable space,two objectives,and non-convexity,is well-suited for solution by PSO.In addition,probe and coupling detuning contribute equivalently to polarizability and compensate for each other owing to Doppler averaging,thereby reducing the optimization variable space by one.By adopting a product form of linear gain and LDR as the fitness function,the PSO achieves rapid convergence.Here,the effectiveness of the PSO results is verified via the total harmonic distortion(THD).The relative error-based LDR calculation method we proposed efficiently measures receiver response linearity with consuming fewer computational resources.This research is expected to offer valuable insights into enhancing the performance of Rydberg-atom-based superheterodyne receivers.
基金National Natural Science Foundation of China(No.U2241205)the Natural Science Basic Research Program of Shaanxi(Nos.2022JC-33,2023-GHZD-35,and 2024JC-ZDXM-25)+1 种基金the Fundamental Research Funds for the Central Universitiesthe National 111 Project to provide fund for conducting experiments。
文摘In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures.
文摘Integration of renewable energy sources into power systems requires efficient multilevel inverters,capable of producing high-quality output voltage with low total harmonic distortion(THD).Conventional multilevel inverters often suffer from high component count,high switching stress,low voltage gain,and increased cost,limiting their practical application.This paper introduces a high-gain novel topology for multilevel inverters with reduced number of total components per level count,low voltage stress on power conductive devices,and minimizing a cost function,which depends on the number of components,standing voltage on switches and diodes,output voltage levels,and gain.The designed topology,which can be applied in photovoltaic(PV)systems,utilizes only one direct current(DC)input supply and a modular structure with the ability of capacitor’s voltage self-balancing.The high gain property and low THD of the proposed topology are two advantages that provide sine output waveform,with no need to a high DC input voltage source.Moreover,generalized topology,consisting of cascaded basic units,has been proposed.A comprehensive method has been proposed to determining the values of DC supplies in this configuration,aiming to minimize redundant switching modes and maximize the voltage levels count.The comparison with some other multilevel inverters confirms the desired performance of the basic version given inverter.A prototype has been also implemented and the experimental results have been obtained to verify the advantages of the proposed 25-level topology.
文摘Since the launch of island-wide special customs operations at Hainan Free Trade Port(Hainan FTP),the proportion of “zero-tariff”imported goods has increased significantly from 21 to 74 percent, and high-quality goods from Southeast Asia can enter Hainan at a more competitive price. If goods contain imported materials and achieve at least 30 percent added value through local processing,they can enter the Chinese mainland market with an exemption from import tariffs, effectively gaining market access across China.
