The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable ...The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable development, furthermore, to choose and form the production structure that is favorable to saving crop resources and protecting the ecology of crops. Plant genetic engineering is the technology of molecule breeding of rearrangement of inheritance materials at the level of molecule directionally, of improving plant properties and of breeding high quality and yield varieties of crops. The prominent effects of the technology on the crop ecological system are human subjective factors increasing as well as violating the nature and intensifying the conflict between human being and nature. Therefore, in plant genetic engineering, crop resources exploitation should follow certain ethic principles. Under the theory of ethics of natural resources, by the means of biologinal-statistics, the author systematically analyzed the possible model of crop resources transfer between generations as well as the transfer mode of magnitude of real materials and magnitude of value.展开更多
Background:Cotton is a significant economic crop that plays an indispensable role in many domains.Gossypium hirsutum L.is the most important fiber crop worldwide and contributes to more than 95%of global cotto n produ...Background:Cotton is a significant economic crop that plays an indispensable role in many domains.Gossypium hirsutum L.is the most important fiber crop worldwide and contributes to more than 95%of global cotto n production.Identifying stable quantitative trait locus(QTLs)controlling fiber quality and yield related traits are necessary prerequisites for marker-assisted selection(MAS).Results:A genetic linkage map was constructed with 312 simple sequence repeat(SSR)loci and 35 linkage groups using JoinMap 4.0;the map spanned 1 929.9 cM,with an average interval between two markers of 6.19 cM,and covered approximately 43.37%of the cotton genome.A total of 74 QTLs controlling fiber quality and 41 QTLs controlling yield-related traits were identified in 4 segregating generations.These QTLs were distributed across 20 chromosomes and collectively explained 1.01%?27.80%of the observed phenotypic variations.In particular,35 stable QTLs could be identified in multiple generations,25 common QTLs were con sistent with those in previous studies,and 15 QTL clusters were found in 11 chromosome segments.Conclusion:These studies provide a theoretical basis for improving cotton yield and fiber quality for molecular marker-assisted selection.展开更多
Background:The utilization of heterosis has greatly improved the productivity of cotton worldwide.However,a major constraint for the large-scale promotion of F_(1) hybrid cotton is artificial emasculation and pollinat...Background:The utilization of heterosis has greatly improved the productivity of cotton worldwide.However,a major constraint for the large-scale promotion of F_(1) hybrid cotton is artificial emasculation and pollination.This study proposed the potential utilization of F_(2) hybrids to improve upland cotton production through a comparative evaluation of hybrid generations.Results:Eight upland cotton varieties were analyzed and crosses were made according to NCII incomplete diallel cross-breeding design in two cotton belts of China.Variance analysis revealed significant differences in agronomic,yield,and fiber quality in both generations and environments.The broad-sense heritability of agronomic and yield traits was relatively higher than quality traits.Furthermore,the narrow-sense heritability of some traits was higher in F_(2) than in the F_(1) generation in both cotton belts.Overall,parental lines Zhong901,ZB,L28,and Z98 were observed with maximum combining ability while combinations with strong special combining ability were ZB×DT,L28×Z98,and ZB×851.The yield traits heterosis was predominant in both generations.However,the level of heterosis was altered with trait,hybrid combination,generation,and environment.Interestingly,L28×Z98 performed outstandingly in Anyang.Its lint yield(LY)was 24.2%higher in F_(1) and 11.6%in F_(2) than that of the control Ruiza 816.The performance of SJ48×Z98 was excellent in Aral which showed 36.5%higher LY in F_(2)and 10.9%in F_(2)than control CCRI 49.Further results revealed most hybrid combinations had shown a low level of heterosis for agronomic and fiber quality traits in both generations.Comparatively,ZB×DT and L28×Z98 showed hybrid vigor for multiple traits in both generations and cotton belts.It is feasible to screen strong heterosis hybrid combinations with fine fiber in early generations.In the two environments,the correlation of some traits showed the same trend,and the correlation degree of Anyang site was higher than that of Aral site,and the correlation of some traits showed the opposite trend.According to the performance of strong heterosis hybrid combinations in different environments,the plant type,yield and fiber traits associated with them can be improved according to the correlation.Conclusions:Through comparative analysis of variance,combining ability,and heterosis in F_(2)and F_(2)hybrids in different cotton belts,this study proposed the potential utilization of F_(2)hybrids to improve upland cotton productivity in China.展开更多
The immense energy potential of natural water vapor cycles,encompassing evaporation,transport,and adsorption,remains substantially underexploited.Recent progress in nanomaterial science and an improved understanding o...The immense energy potential of natural water vapor cycles,encompassing evaporation,transport,and adsorption,remains substantially underexploited.Recent progress in nanomaterial science and an improved understanding of water-surface interactions have shown that because of quantum confinement effects and increased surface reactivity,nanoscale materials have exceptional electrical generation abilities through interfacial dynamics with aqueous phases.Hydrovoltaic technology has emerged as a novel energy conversion method that harnesses liquid-solid interfacial phenomena including surface slippage,frictional contact,evaporation dynamics,and moisture concentration gradients to produce electrical outputs.This review summarizes advances in graphene-based carbon materials for hydrovoltaic applications,addressing four critical aspects:(1)fundamental characteristics of graphene-water interfaces,(2)interfacial charge generation mechanisms at liquid-solid boundaries,(3)three principal electricity generation modes(flow-induced,evaporation-driven,and moisture gradient-enabled power generation),and(4)practical implementation scenarios.We also propose ways to improve the energy conversion efficiency and scale-up of the current technology for its use in self-powered systems,flexible energy storage batteries,humidity sensors,and personal thermal management devices.展开更多
To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a b...To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a benchmark scramjet performance evaluation model.Based on the test data of typical flying point of Mach 7 with the altitude of 29 km,the reliability of the model was verified.The deviations of parameters such as the to⁃tal pressure loss of combustor between the model and the test data were analyzed.Furtherly,an analytical method for post-combustion magnetohydrodynamic power generation was established;by embedding the above method into the overall performance evaluation model,performance prediction considering the power generation effect was realized.Finally,based on the above model,variety regulations of the inlet and the outlet parameters of the power generation channel and performance parameters including the engine specific impulse and the unit thrust under different enthalpy extraction ratios and load factors were analyzed.It could be concluded that the model can reliably predict the variations of key parameters.As the value of the load factor increases,the value of the conduc⁃tivity required to reach the specified enthalpy extraction ratio first decreases and then increases,which is approxi⁃mately parabolic.In order to reduce the demand for the gas conductivity for MHD power generation,the load fac⁃tor should be around 0.5.When the load factor is 0.4 and the magnetic induction intensity is 2.5 T,if the enthalpy extraction ratio reaches 0.5%,the engine specific impulse performance reduces about 3.58%.展开更多
Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as...Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles.展开更多
The generation of optical vortices from nonlinear photonic crystals(NPCs)with spatially modulated second-order nonlinearity offers a promising approach to extend the working wavelength and topological charge of vortex...The generation of optical vortices from nonlinear photonic crystals(NPCs)with spatially modulated second-order nonlinearity offers a promising approach to extend the working wavelength and topological charge of vortex beams for various applications.In this work,the second harmonic(SH)optical vortex beams generated from nonlinear fork gratings under Gaussian beam illumination are numerically investigated.The far-field intensity and phase distributions,as well as the orbital angular momentum(OAM)spectra of the SH beams,are analyzed for different structural topological charges and diffraction orders.Results reveal that higher-order diffraction and larger structural topological charges lead to angular interference patterns and non-uniform intensity distributions,deviating from the standard vortex profile.To optimize the SH vortex quality,the effects of the fundamental wave beam waist,crystal thickness,and grating duty cycle are explored.It is shown that increasing the beam waist can effectively suppress diffraction order interference and improve the beam’s quality.This study provides theoretical guidance for enhancing the performance of nonlinear optical devices based on NPCs.展开更多
Soft polymer optical fiber(SPOF)has shown great potential in optical-based wearable and implantable biosensors due to its excellent mechanical properties and optical guiding characteristics.However,the multimodality c...Soft polymer optical fiber(SPOF)has shown great potential in optical-based wearable and implantable biosensors due to its excellent mechanical properties and optical guiding characteristics.However,the multimodality characteristics of SPOF limit their integration with traditional fiber optic sensors.This article introduces for the first time a flexible fiber optic vibration sensor based on laser interference technology,which can be applied to vibration measurement under high stretch conditions.This sensor utilizes elastic optical fibers made of polydimethylsiloxane(PDMS)as sensing elements,combined with phase generating carrier technology,to achieve vibration measurement at 50−260 Hz within the stretch range of 0−42%.展开更多
Drone swarm systems,equipped with photoelectric imaging and intelligent target perception,are essential for reconnaissance and strike missions in complex and high-risk environments.They excel in information sharing,an...Drone swarm systems,equipped with photoelectric imaging and intelligent target perception,are essential for reconnaissance and strike missions in complex and high-risk environments.They excel in information sharing,anti-jamming capabilities,and combat performance,making them critical for future warfare.However,varied perspectives in collaborative combat scenarios pose challenges to object detection,hindering traditional detection algorithms and reducing accuracy.Limited angle-prior data and sparse samples further complicate detection.This paper presents the Multi-View Collaborative Detection System,which tackles the challenges of multi-view object detection in collaborative combat scenarios.The system is designed to enhance multi-view image generation and detection algorithms,thereby improving the accuracy and efficiency of object detection across varying perspectives.First,an observation model for three-dimensional targets through line-of-sight angle transformation is constructed,and a multi-view image generation algorithm based on the Pix2Pix network is designed.For object detection,YOLOX is utilized,and a deep feature extraction network,BA-RepCSPDarknet,is developed to address challenges related to small target scale and feature extraction challenges.Additionally,a feature fusion network NS-PAFPN is developed to mitigate the issue of deep feature map information loss in UAV images.A visual attention module(BAM)is employed to manage appearance differences under varying angles,while a feature mapping module(DFM)prevents fine-grained feature loss.These advancements lead to the development of BA-YOLOX,a multi-view object detection network model suitable for drone platforms,enhancing accuracy and effectively targeting small objects.展开更多
Architecture framework has become an effective method recently to describe the system of systems(SoS)architecture,such as the United States(US)Department of Defense Architecture Framework Version 2.0(DoDAF2.0).As a vi...Architecture framework has become an effective method recently to describe the system of systems(SoS)architecture,such as the United States(US)Department of Defense Architecture Framework Version 2.0(DoDAF2.0).As a viewpoint in DoDAF2.0,the operational viewpoint(OV)describes operational activities,nodes,and resource flows.The OV models are important for SoS architecture development.However,as the SoS complexity increases,constructing OV models with traditional methods exposes shortcomings,such as inefficient data collection and low modeling standards.Therefore,we propose an intelligent modeling method for five OV models,including operational resource flow OV-2,organizational relationships OV-4,operational activity hierarchy OV-5a,operational activities model OV-5b,and operational activity sequences OV-6c.The main idea of the method is to extract OV architecture data from text and generate interoperable OV models.First,we construct the OV meta model based on the DoDAF2.0 meta model(DM2).Second,OV architecture named entities is recognized from text based on the bidirectional long short-term memory and conditional random field(BiLSTM-CRF)model.And OV architecture relationships are collected with relationship extraction rules.Finally,we define the generation rules for OV models and develop an OV modeling tool.We use unmanned surface vehicles(USV)swarm target defense SoS architecture as a case to verify the feasibility and effectiveness of the intelligent modeling method.展开更多
基于对新一代GPS(geometrical product specification and verification)中关键操作技术的深入分析,揭示提取与滤波、拟合之间固有的内在规律性,给出操作间参数的选用原则,为统筹优化几何误差数字化评定中的操作策略提供技术基础;最终...基于对新一代GPS(geometrical product specification and verification)中关键操作技术的深入分析,揭示提取与滤波、拟合之间固有的内在规律性,给出操作间参数的选用原则,为统筹优化几何误差数字化评定中的操作策略提供技术基础;最终通过实例验证关键操作集成化思想对几何误差评定的高效稳定性,不仅有利于实现几何误差数字化计量精度和成本的优化,而且还推进了新一代GPS标准体系关键技术的应用研究。展开更多
上世纪90年代后期以来,“在路上”成为中国文学界的流行话语,它源于“垮掉的一代”(BG)作家凯鲁亚克的小说《在路上》(On the Road),其起源语境、语义与BG相关。小说中BG伙伴横穿美国,在路上酗酒、吸毒、滥交,反抗美国现存体制,体验主...上世纪90年代后期以来,“在路上”成为中国文学界的流行话语,它源于“垮掉的一代”(BG)作家凯鲁亚克的小说《在路上》(On the Road),其起源语境、语义与BG相关。小说中BG伙伴横穿美国,在路上酗酒、吸毒、滥交,反抗美国现存体制,体验主流文化之外另一种生活。他们为一种莫名的想望不知疲倦地奔走,在疯狂中感觉自我,所以“在路上”语义非常复杂。中国移植者将它从其起源语境中剥离出来,抽空其原义,对其作望文生义的理解,使其抽象化、普泛化,弱化了它对于中国文化建构的价值与意义。展开更多
Shortly after the celebration of twenty years of the narratology seminar at the CRAL(CNRS/EHESS)in Paris,Cao Danhong,professor of French language and literature at Nanjing University in China,conducted an interview wi...Shortly after the celebration of twenty years of the narratology seminar at the CRAL(CNRS/EHESS)in Paris,Cao Danhong,professor of French language and literature at Nanjing University in China,conducted an interview with John Pier,one of the organizers of the seminar at the CRAL and also one of the most active researchers in narratology.Based on the evolution of the Seminar's work over the past twenty years,John Pier briefly reviewed the achievements of Western narratology since its foundation,suggested reexamining its evolution by dividing it into three"generations",and reaffirmed its fundamental characteristics such as transborderality,transmediality,and transdisciplinarity.Also discussed were paths for the future development of narratology with an emphasis on comparative research,diachronic research,and historiography.展开更多
文摘The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable development, furthermore, to choose and form the production structure that is favorable to saving crop resources and protecting the ecology of crops. Plant genetic engineering is the technology of molecule breeding of rearrangement of inheritance materials at the level of molecule directionally, of improving plant properties and of breeding high quality and yield varieties of crops. The prominent effects of the technology on the crop ecological system are human subjective factors increasing as well as violating the nature and intensifying the conflict between human being and nature. Therefore, in plant genetic engineering, crop resources exploitation should follow certain ethic principles. Under the theory of ethics of natural resources, by the means of biologinal-statistics, the author systematically analyzed the possible model of crop resources transfer between generations as well as the transfer mode of magnitude of real materials and magnitude of value.
基金supported by the National Natural Science Foundation of China(31371668)the National Agricultural Science and Technology Innovation project for CAAS(CAAS-ASTIP-2016-ICR)
文摘Background:Cotton is a significant economic crop that plays an indispensable role in many domains.Gossypium hirsutum L.is the most important fiber crop worldwide and contributes to more than 95%of global cotto n production.Identifying stable quantitative trait locus(QTLs)controlling fiber quality and yield related traits are necessary prerequisites for marker-assisted selection(MAS).Results:A genetic linkage map was constructed with 312 simple sequence repeat(SSR)loci and 35 linkage groups using JoinMap 4.0;the map spanned 1 929.9 cM,with an average interval between two markers of 6.19 cM,and covered approximately 43.37%of the cotton genome.A total of 74 QTLs controlling fiber quality and 41 QTLs controlling yield-related traits were identified in 4 segregating generations.These QTLs were distributed across 20 chromosomes and collectively explained 1.01%?27.80%of the observed phenotypic variations.In particular,35 stable QTLs could be identified in multiple generations,25 common QTLs were con sistent with those in previous studies,and 15 QTL clusters were found in 11 chromosome segments.Conclusion:These studies provide a theoretical basis for improving cotton yield and fiber quality for molecular marker-assisted selection.
基金sponsored by funds from the Zhongyuan Academician Foundation (212101510001)the Fundamental Research Funds for State Key Laboratory of Cotton Biology (CB2021C08)the General Program of the National Natural Science Foundation of China (31871679)
文摘Background:The utilization of heterosis has greatly improved the productivity of cotton worldwide.However,a major constraint for the large-scale promotion of F_(1) hybrid cotton is artificial emasculation and pollination.This study proposed the potential utilization of F_(2) hybrids to improve upland cotton production through a comparative evaluation of hybrid generations.Results:Eight upland cotton varieties were analyzed and crosses were made according to NCII incomplete diallel cross-breeding design in two cotton belts of China.Variance analysis revealed significant differences in agronomic,yield,and fiber quality in both generations and environments.The broad-sense heritability of agronomic and yield traits was relatively higher than quality traits.Furthermore,the narrow-sense heritability of some traits was higher in F_(2) than in the F_(1) generation in both cotton belts.Overall,parental lines Zhong901,ZB,L28,and Z98 were observed with maximum combining ability while combinations with strong special combining ability were ZB×DT,L28×Z98,and ZB×851.The yield traits heterosis was predominant in both generations.However,the level of heterosis was altered with trait,hybrid combination,generation,and environment.Interestingly,L28×Z98 performed outstandingly in Anyang.Its lint yield(LY)was 24.2%higher in F_(1) and 11.6%in F_(2) than that of the control Ruiza 816.The performance of SJ48×Z98 was excellent in Aral which showed 36.5%higher LY in F_(2)and 10.9%in F_(2)than control CCRI 49.Further results revealed most hybrid combinations had shown a low level of heterosis for agronomic and fiber quality traits in both generations.Comparatively,ZB×DT and L28×Z98 showed hybrid vigor for multiple traits in both generations and cotton belts.It is feasible to screen strong heterosis hybrid combinations with fine fiber in early generations.In the two environments,the correlation of some traits showed the same trend,and the correlation degree of Anyang site was higher than that of Aral site,and the correlation of some traits showed the opposite trend.According to the performance of strong heterosis hybrid combinations in different environments,the plant type,yield and fiber traits associated with them can be improved according to the correlation.Conclusions:Through comparative analysis of variance,combining ability,and heterosis in F_(2)and F_(2)hybrids in different cotton belts,this study proposed the potential utilization of F_(2)hybrids to improve upland cotton productivity in China.
文摘The immense energy potential of natural water vapor cycles,encompassing evaporation,transport,and adsorption,remains substantially underexploited.Recent progress in nanomaterial science and an improved understanding of water-surface interactions have shown that because of quantum confinement effects and increased surface reactivity,nanoscale materials have exceptional electrical generation abilities through interfacial dynamics with aqueous phases.Hydrovoltaic technology has emerged as a novel energy conversion method that harnesses liquid-solid interfacial phenomena including surface slippage,frictional contact,evaporation dynamics,and moisture concentration gradients to produce electrical outputs.This review summarizes advances in graphene-based carbon materials for hydrovoltaic applications,addressing four critical aspects:(1)fundamental characteristics of graphene-water interfaces,(2)interfacial charge generation mechanisms at liquid-solid boundaries,(3)three principal electricity generation modes(flow-induced,evaporation-driven,and moisture gradient-enabled power generation),and(4)practical implementation scenarios.We also propose ways to improve the energy conversion efficiency and scale-up of the current technology for its use in self-powered systems,flexible energy storage batteries,humidity sensors,and personal thermal management devices.
文摘To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a benchmark scramjet performance evaluation model.Based on the test data of typical flying point of Mach 7 with the altitude of 29 km,the reliability of the model was verified.The deviations of parameters such as the to⁃tal pressure loss of combustor between the model and the test data were analyzed.Furtherly,an analytical method for post-combustion magnetohydrodynamic power generation was established;by embedding the above method into the overall performance evaluation model,performance prediction considering the power generation effect was realized.Finally,based on the above model,variety regulations of the inlet and the outlet parameters of the power generation channel and performance parameters including the engine specific impulse and the unit thrust under different enthalpy extraction ratios and load factors were analyzed.It could be concluded that the model can reliably predict the variations of key parameters.As the value of the load factor increases,the value of the conduc⁃tivity required to reach the specified enthalpy extraction ratio first decreases and then increases,which is approxi⁃mately parabolic.In order to reduce the demand for the gas conductivity for MHD power generation,the load fac⁃tor should be around 0.5.When the load factor is 0.4 and the magnetic induction intensity is 2.5 T,if the enthalpy extraction ratio reaches 0.5%,the engine specific impulse performance reduces about 3.58%.
文摘Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles.
基金supported by the National Nat-ural Science Foundation of China(Nos.12192251,12174185,92163216,and 62288101).
文摘The generation of optical vortices from nonlinear photonic crystals(NPCs)with spatially modulated second-order nonlinearity offers a promising approach to extend the working wavelength and topological charge of vortex beams for various applications.In this work,the second harmonic(SH)optical vortex beams generated from nonlinear fork gratings under Gaussian beam illumination are numerically investigated.The far-field intensity and phase distributions,as well as the orbital angular momentum(OAM)spectra of the SH beams,are analyzed for different structural topological charges and diffraction orders.Results reveal that higher-order diffraction and larger structural topological charges lead to angular interference patterns and non-uniform intensity distributions,deviating from the standard vortex profile.To optimize the SH vortex quality,the effects of the fundamental wave beam waist,crystal thickness,and grating duty cycle are explored.It is shown that increasing the beam waist can effectively suppress diffraction order interference and improve the beam’s quality.This study provides theoretical guidance for enhancing the performance of nonlinear optical devices based on NPCs.
文摘Soft polymer optical fiber(SPOF)has shown great potential in optical-based wearable and implantable biosensors due to its excellent mechanical properties and optical guiding characteristics.However,the multimodality characteristics of SPOF limit their integration with traditional fiber optic sensors.This article introduces for the first time a flexible fiber optic vibration sensor based on laser interference technology,which can be applied to vibration measurement under high stretch conditions.This sensor utilizes elastic optical fibers made of polydimethylsiloxane(PDMS)as sensing elements,combined with phase generating carrier technology,to achieve vibration measurement at 50−260 Hz within the stretch range of 0−42%.
基金supported by the Natural Science Foundation of China,Grant No.62103052.
文摘Drone swarm systems,equipped with photoelectric imaging and intelligent target perception,are essential for reconnaissance and strike missions in complex and high-risk environments.They excel in information sharing,anti-jamming capabilities,and combat performance,making them critical for future warfare.However,varied perspectives in collaborative combat scenarios pose challenges to object detection,hindering traditional detection algorithms and reducing accuracy.Limited angle-prior data and sparse samples further complicate detection.This paper presents the Multi-View Collaborative Detection System,which tackles the challenges of multi-view object detection in collaborative combat scenarios.The system is designed to enhance multi-view image generation and detection algorithms,thereby improving the accuracy and efficiency of object detection across varying perspectives.First,an observation model for three-dimensional targets through line-of-sight angle transformation is constructed,and a multi-view image generation algorithm based on the Pix2Pix network is designed.For object detection,YOLOX is utilized,and a deep feature extraction network,BA-RepCSPDarknet,is developed to address challenges related to small target scale and feature extraction challenges.Additionally,a feature fusion network NS-PAFPN is developed to mitigate the issue of deep feature map information loss in UAV images.A visual attention module(BAM)is employed to manage appearance differences under varying angles,while a feature mapping module(DFM)prevents fine-grained feature loss.These advancements lead to the development of BA-YOLOX,a multi-view object detection network model suitable for drone platforms,enhancing accuracy and effectively targeting small objects.
基金National Natural Science Foundation of China(71690233,71971213,71901214)。
文摘Architecture framework has become an effective method recently to describe the system of systems(SoS)architecture,such as the United States(US)Department of Defense Architecture Framework Version 2.0(DoDAF2.0).As a viewpoint in DoDAF2.0,the operational viewpoint(OV)describes operational activities,nodes,and resource flows.The OV models are important for SoS architecture development.However,as the SoS complexity increases,constructing OV models with traditional methods exposes shortcomings,such as inefficient data collection and low modeling standards.Therefore,we propose an intelligent modeling method for five OV models,including operational resource flow OV-2,organizational relationships OV-4,operational activity hierarchy OV-5a,operational activities model OV-5b,and operational activity sequences OV-6c.The main idea of the method is to extract OV architecture data from text and generate interoperable OV models.First,we construct the OV meta model based on the DoDAF2.0 meta model(DM2).Second,OV architecture named entities is recognized from text based on the bidirectional long short-term memory and conditional random field(BiLSTM-CRF)model.And OV architecture relationships are collected with relationship extraction rules.Finally,we define the generation rules for OV models and develop an OV modeling tool.We use unmanned surface vehicles(USV)swarm target defense SoS architecture as a case to verify the feasibility and effectiveness of the intelligent modeling method.
文摘基于对新一代GPS(geometrical product specification and verification)中关键操作技术的深入分析,揭示提取与滤波、拟合之间固有的内在规律性,给出操作间参数的选用原则,为统筹优化几何误差数字化评定中的操作策略提供技术基础;最终通过实例验证关键操作集成化思想对几何误差评定的高效稳定性,不仅有利于实现几何误差数字化计量精度和成本的优化,而且还推进了新一代GPS标准体系关键技术的应用研究。
文摘上世纪90年代后期以来,“在路上”成为中国文学界的流行话语,它源于“垮掉的一代”(BG)作家凯鲁亚克的小说《在路上》(On the Road),其起源语境、语义与BG相关。小说中BG伙伴横穿美国,在路上酗酒、吸毒、滥交,反抗美国现存体制,体验主流文化之外另一种生活。他们为一种莫名的想望不知疲倦地奔走,在疯狂中感觉自我,所以“在路上”语义非常复杂。中国移植者将它从其起源语境中剥离出来,抽空其原义,对其作望文生义的理解,使其抽象化、普泛化,弱化了它对于中国文化建构的价值与意义。
文摘Shortly after the celebration of twenty years of the narratology seminar at the CRAL(CNRS/EHESS)in Paris,Cao Danhong,professor of French language and literature at Nanjing University in China,conducted an interview with John Pier,one of the organizers of the seminar at the CRAL and also one of the most active researchers in narratology.Based on the evolution of the Seminar's work over the past twenty years,John Pier briefly reviewed the achievements of Western narratology since its foundation,suggested reexamining its evolution by dividing it into three"generations",and reaffirmed its fundamental characteristics such as transborderality,transmediality,and transdisciplinarity.Also discussed were paths for the future development of narratology with an emphasis on comparative research,diachronic research,and historiography.