A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,t...A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases.展开更多
Herein the use of rare-earth compounds in catalytic reduction systems for the end-group functionalization of carboxyl-terminated low-molecularweight fluoropolymers was explored.Leveraging the high catalytic activity a...Herein the use of rare-earth compounds in catalytic reduction systems for the end-group functionalization of carboxyl-terminated low-molecularweight fluoropolymers was explored.Leveraging the high catalytic activity and selectivity of rare-earth compounds along with no residual impact on polymer product's performance,highly efficient catalytic reduction systems containing sodium borohydride(NaBH_(4))and rare-earth chloride(RECl_(3))were specifically designed for a telechelic carboxyl-terminated liquid fluoroeslastomer,aiming to facilitate the conversion of chainend carboxyl groups into hydroxyl groups and improvement in end-group reactivity.To achieve this,lanthanum chloride(LaCl_(3)),cerium chloride(CeCl_(3)),and neodymium chloride(NdCl_(3))were used separately to form catalytic reduction systems with NaBH_(4).The effects of solvent dosage,reaction temperature,reaction time length,and reductant dosage on carboxylic conversion were investigated,and the molecular chain structure,molecular weight,and functional group content of the raw materials and the products were analyzed and characterized by means of infrared spectroscopy(FTIR),proton nuclear magnetic resonance(^(1)H-NMR),fluorine-19 nuclear magnetic resonance(^(19)F-NMR),gel permeation chromatography(GPC),and chemical titration.Moreover,the catalytic activity and selectivity of the rare-earth chlorides,as well as the corresponding underlying interactions were discussed.Results indicated that the rare-earth-containing catalytic reduction systems studied in this work could efficiently convert the chain-end carboxyl groups into highly active hydroxyl groups,with a highest conversion up to 87.0%and differing catalytic reduction activities ranked as NaBH_(4)/CeCl_(3)>NaBH_(4)/LaCl_(3)>NaBH_(4)/NdCl_(3).Compared with the conventional lithium aluminum hydride(LiAIH_(4))reduction system,the NaBH_(4)/RECl_(3)systems provide multiple advantages such as mild reaction conditions,high conversion ratio with good selectivity,and environmental innocuity,and are potentially applicable as new reduction-catalysis combinations for the synthesis and functionalization of polymer materials.展开更多
To solve the problem of providing the best initial situation for terminal guidance when multiple missiles intercept multiple targets,a group cooperative midcourse guidance law(GCMGL)considering time-to-go is proposed....To solve the problem of providing the best initial situation for terminal guidance when multiple missiles intercept multiple targets,a group cooperative midcourse guidance law(GCMGL)considering time-to-go is proposed.Firstly,a threedimensional(3D)guidance model is established and a cooperative trajectory shaping guidance law is given.Secondly,for estimating the unknown target maneuvering acceleration,an adaptive disturbance observer(ADO)is designed,combining finitetime theory with a radial basis function(RBF)neural network,and the convergence of the estimation error is proven using Lyapunov stability theory.Then,to ensure time-to-go cooperation among missiles within the same group and across different groups,the group consensus protocols of virtual collision point mean and the inter-group cooperative consensus protocol are designed respectively.Based on the group consensus protocols,the virtual collision point cooperative guidance law is given,and the finite-time convergence is proved by Lyapunov stability theory.Simultaneously,combined with trajectory shaping guidance law,virtual collision point cooperative guidance law and the intergroup cooperative consensus protocol,the design of GCMGL considering time-to-go is given.Finally,numerical simulation results show the effectiveness and the superiority of the proposed GCMGL.展开更多
1.Journal of Yunnan Agricultural University is spon-sored by Yunnan Agricultural University and has been published since1986.The journal was initially pub-lished semi-annually,and changed to quarterly in1989and bimont...1.Journal of Yunnan Agricultural University is spon-sored by Yunnan Agricultural University and has been published since1986.The journal was initially pub-lished semi-annually,and changed to quarterly in1989and bimonthly in2004.As a comprehensive sci-entific periodical publication in China and abroad,Journal of Yunnan Agricultural University won the ti-tles of Chinese core journals,the core of Chinais sci-ence and technology journals,the core of Chinai ag-ricultural science journals.展开更多
Contributions falling into the following categories will be considered for publication: Original research papers, reviews, note. Please ensure that you select the appropriate article type from the list of options when...Contributions falling into the following categories will be considered for publication: Original research papers, reviews, note. Please ensure that you select the appropriate article type from the list of options when making your submission. Authors contributing to special issues should ensure that they select the special issue article type from this list.展开更多
Aims and scope Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and pra...Aims and scope Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and practical aspects of systems engineering,electronics and related research areas.The journal welcomes high quality original papers from a wide range of countries.The scope of the journal includes systems engineering,military systems,electronic technology,defense electronic technology,control theory and practice,software algorithm and simulation,reliability,computer development and application,and other topics in all related fields.展开更多
Journal of Systems Engineering and Electronics,keeping abreast with the development trend of scienceand technology worldwide, reports the latest developmentsand achievements in both theoretical andpractical aspects of...Journal of Systems Engineering and Electronics,keeping abreast with the development trend of scienceand technology worldwide, reports the latest developmentsand achievements in both theoretical andpractical aspects of systems engineering, electronicsand related research areas. The journal welcomes highquality original papers from a wide range of countries.The scope of the journal includes systems engineering,military systems, electronic technology, defense electronictechnology, control theory and practice, softwarealgorithm and simulation, reliability, computerdevelopment and application, and other topics in allrelated fields.展开更多
Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and practical aspects ...Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and practical aspects of systems engineering,展开更多
Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest develop- ments and achievements in both theoretical and...Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest develop- ments and achievements in both theoretical and practical aspects of systems engineering, electronics and related research areas. The journal welcomes high quality original papers from a wide range of countries. The scope of the journal includes systems engineering, military systems, electronic technology, defense elec- tronic technology, control theory and practice, soft- ware algorithm and simulation, reliability, computer development and application, and other topics in all related fields.展开更多
Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and p...Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and practical aspects of systems engineering, electronics and related research areas.展开更多
INTRODUCTION Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,reviews,note.Please ensure that you select the appropriate article type from ...INTRODUCTION Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,reviews,note.Please ensure that you select the appropriate article type from the list of options when making your submission.Authors contributing to special issues should ensure that they select the special issue article type from展开更多
Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and p...Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and practical aspects of systems engineering, electronics and related research areas.展开更多
Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and p...Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and practical aspeets of systems engineering, electronics and related research areas. The journal welcomes high quality original papers from a wide range of countries.展开更多
Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest develop- ments and achievements in both theoretical and practical aspe...Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest develop- ments and achievements in both theoretical and practical aspects of systems engineering, electronics and related research areas. The journal welcomes high quality original papers from a wide range of countries. The scope of the journal includes systems engineering, military systems, electronic technology, defense elec- tronic technology, control theory and practice, soft- ware algorithm and simulation, reliability, computer development and application, and other topics in all related fields.展开更多
Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and aclfievements in both theoretical and ...Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and aclfievements in both theoretical and practical aspects of systems engineering, electronics and related research areas. The journal welcomes high quality original papers from a wide range of countries. The scope of the journal includes systems engineering, military systems, electronic technology, defense electronic technology, control theory and practice, software algorithm and simulation, reliability, computer development and application, and other topics in all related fields.展开更多
Aims and scope Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and pra...Aims and scope Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and practical aspects of systems engineering,electronics展开更多
基金Supported by National Natural Science Foundation of China(61911530398,12231012)Consultancy Project by the Chinese Academy of Engineering(2022-JB-06,2023-JB-12)+3 种基金the Natural Science Foundation of Fujian Province of China(2021J01621)Special Projects of the Central Government Guiding Local Science and Technology Development(2021L3018)Royal Society of Edinburgh(RSE1832)Engineering and Physical Sciences Research Council(EP/W522521/1).
文摘A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases.
文摘Herein the use of rare-earth compounds in catalytic reduction systems for the end-group functionalization of carboxyl-terminated low-molecularweight fluoropolymers was explored.Leveraging the high catalytic activity and selectivity of rare-earth compounds along with no residual impact on polymer product's performance,highly efficient catalytic reduction systems containing sodium borohydride(NaBH_(4))and rare-earth chloride(RECl_(3))were specifically designed for a telechelic carboxyl-terminated liquid fluoroeslastomer,aiming to facilitate the conversion of chainend carboxyl groups into hydroxyl groups and improvement in end-group reactivity.To achieve this,lanthanum chloride(LaCl_(3)),cerium chloride(CeCl_(3)),and neodymium chloride(NdCl_(3))were used separately to form catalytic reduction systems with NaBH_(4).The effects of solvent dosage,reaction temperature,reaction time length,and reductant dosage on carboxylic conversion were investigated,and the molecular chain structure,molecular weight,and functional group content of the raw materials and the products were analyzed and characterized by means of infrared spectroscopy(FTIR),proton nuclear magnetic resonance(^(1)H-NMR),fluorine-19 nuclear magnetic resonance(^(19)F-NMR),gel permeation chromatography(GPC),and chemical titration.Moreover,the catalytic activity and selectivity of the rare-earth chlorides,as well as the corresponding underlying interactions were discussed.Results indicated that the rare-earth-containing catalytic reduction systems studied in this work could efficiently convert the chain-end carboxyl groups into highly active hydroxyl groups,with a highest conversion up to 87.0%and differing catalytic reduction activities ranked as NaBH_(4)/CeCl_(3)>NaBH_(4)/LaCl_(3)>NaBH_(4)/NdCl_(3).Compared with the conventional lithium aluminum hydride(LiAIH_(4))reduction system,the NaBH_(4)/RECl_(3)systems provide multiple advantages such as mild reaction conditions,high conversion ratio with good selectivity,and environmental innocuity,and are potentially applicable as new reduction-catalysis combinations for the synthesis and functionalization of polymer materials.
基金supported by the National Natural Science Foundation of China(62003264).
文摘To solve the problem of providing the best initial situation for terminal guidance when multiple missiles intercept multiple targets,a group cooperative midcourse guidance law(GCMGL)considering time-to-go is proposed.Firstly,a threedimensional(3D)guidance model is established and a cooperative trajectory shaping guidance law is given.Secondly,for estimating the unknown target maneuvering acceleration,an adaptive disturbance observer(ADO)is designed,combining finitetime theory with a radial basis function(RBF)neural network,and the convergence of the estimation error is proven using Lyapunov stability theory.Then,to ensure time-to-go cooperation among missiles within the same group and across different groups,the group consensus protocols of virtual collision point mean and the inter-group cooperative consensus protocol are designed respectively.Based on the group consensus protocols,the virtual collision point cooperative guidance law is given,and the finite-time convergence is proved by Lyapunov stability theory.Simultaneously,combined with trajectory shaping guidance law,virtual collision point cooperative guidance law and the intergroup cooperative consensus protocol,the design of GCMGL considering time-to-go is given.Finally,numerical simulation results show the effectiveness and the superiority of the proposed GCMGL.
文摘1.Journal of Yunnan Agricultural University is spon-sored by Yunnan Agricultural University and has been published since1986.The journal was initially pub-lished semi-annually,and changed to quarterly in1989and bimonthly in2004.As a comprehensive sci-entific periodical publication in China and abroad,Journal of Yunnan Agricultural University won the ti-tles of Chinese core journals,the core of Chinais sci-ence and technology journals,the core of Chinai ag-ricultural science journals.
文摘Contributions falling into the following categories will be considered for publication: Original research papers, reviews, note. Please ensure that you select the appropriate article type from the list of options when making your submission. Authors contributing to special issues should ensure that they select the special issue article type from this list.
文摘Aims and scope Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and practical aspects of systems engineering,electronics and related research areas.The journal welcomes high quality original papers from a wide range of countries.The scope of the journal includes systems engineering,military systems,electronic technology,defense electronic technology,control theory and practice,software algorithm and simulation,reliability,computer development and application,and other topics in all related fields.
文摘Journal of Systems Engineering and Electronics,keeping abreast with the development trend of scienceand technology worldwide, reports the latest developmentsand achievements in both theoretical andpractical aspects of systems engineering, electronicsand related research areas. The journal welcomes highquality original papers from a wide range of countries.The scope of the journal includes systems engineering,military systems, electronic technology, defense electronictechnology, control theory and practice, softwarealgorithm and simulation, reliability, computerdevelopment and application, and other topics in allrelated fields.
文摘Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and practical aspects of systems engineering,
文摘Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest develop- ments and achievements in both theoretical and practical aspects of systems engineering, electronics and related research areas. The journal welcomes high quality original papers from a wide range of countries. The scope of the journal includes systems engineering, military systems, electronic technology, defense elec- tronic technology, control theory and practice, soft- ware algorithm and simulation, reliability, computer development and application, and other topics in all related fields.
文摘Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and practical aspects of systems engineering, electronics and related research areas.
文摘INTRODUCTION Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,reviews,note.Please ensure that you select the appropriate article type from the list of options when making your submission.Authors contributing to special issues should ensure that they select the special issue article type from
文摘Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and practical aspects of systems engineering, electronics and related research areas.
文摘Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and achievements in both theoretical and practical aspeets of systems engineering, electronics and related research areas. The journal welcomes high quality original papers from a wide range of countries.
文摘Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest develop- ments and achievements in both theoretical and practical aspects of systems engineering, electronics and related research areas. The journal welcomes high quality original papers from a wide range of countries. The scope of the journal includes systems engineering, military systems, electronic technology, defense elec- tronic technology, control theory and practice, soft- ware algorithm and simulation, reliability, computer development and application, and other topics in all related fields.
文摘Aims and scope Journal of Systems Engineering and Electronics, keeping abreast with the development trend of science and technology worldwide, reports the latest developments and aclfievements in both theoretical and practical aspects of systems engineering, electronics and related research areas. The journal welcomes high quality original papers from a wide range of countries. The scope of the journal includes systems engineering, military systems, electronic technology, defense electronic technology, control theory and practice, software algorithm and simulation, reliability, computer development and application, and other topics in all related fields.
文摘Aims and scope Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest developments and achievements in both theoretical and practical aspects of systems engineering,electronics
