Typically,a computer has infectivity as soon as it is infected.It is a reality that no antivirus programming can identify and eliminate all kinds of viruses,suggesting that infections would persevere on the Internet.T...Typically,a computer has infectivity as soon as it is infected.It is a reality that no antivirus programming can identify and eliminate all kinds of viruses,suggesting that infections would persevere on the Internet.To understand the dynamics of the virus propagation in a better way,a computer virus spread model with fuzzy parameters is presented in this work.It is assumed that all infected computers do not have the same contribution to the virus transmission process and each computer has a different degree of infectivity,which depends on the quantity of virus.Considering this,the parametersβandγbeing functions of the computer virus load,are considered fuzzy numbers.Using fuzzy theory helps us understand the spread of computer viruses more realistically as these parameters have fixed values in classical models.The essential features of the model,like reproduction number and equilibrium analysis,are discussed in fuzzy senses.Moreover,with fuzziness,two numerical methods,the forward Euler technique,and a nonstandard finite difference(NSFD)scheme,respectively,are developed and analyzed.In the evidence of the numerical simulations,the proposed NSFD method preserves the main features of the dynamic system.It can be considered a reliable tool to predict such types of solutions.展开更多
The Markov property of Markov process functionals which are frequently used in economy, finance, engineering and statistic analysis is studied. The conditions to judge Markov property of some important Markov process ...The Markov property of Markov process functionals which are frequently used in economy, finance, engineering and statistic analysis is studied. The conditions to judge Markov property of some important Markov process functionals are presented, the following conclusions are obtained: the multidimensional process with independent increments is a multidimensional Markov process; the functional in the form of path integral of process with independent increments is a Markov process; the surplus process with the doubly stochastic Poisson process is a vector Markov process. The conditions for linear transformation of vector Markov process being still a Markov process are given.展开更多
Based on coupled-mode theo ry , the eigenvalue equation of five-layered long-period fiber grating(LPFG) sens or with Ag film and gas-sensitive film overlays are firstly studied. The probl em of resolving complex eigen...Based on coupled-mode theo ry , the eigenvalue equation of five-layered long-period fiber grating(LPFG) sens or with Ag film and gas-sensitive film overlays are firstly studied. The probl em of resolving complex eigenvalue equation on five-layered LPFG is analyzed, a nd the method of resolution is also given. Then the eigenvalue equation of three -layered metal cladding LPFG is analyzed, and the complex transcendental equati on is also discussed. The computing result shows that the coupling between the l ow-order EH modes and the core mode is much stronger than that between the low -order HE modes and the core mode.展开更多
For the potential type operatorTФf(x)=∫RnФ(x-y)f(y)dy,where Ф is a non-negative locally integrable function on R^n and satisfies weak growth condition, a two-weight weak-type (p,q) inequality for TФ is ob...For the potential type operatorTФf(x)=∫RnФ(x-y)f(y)dy,where Ф is a non-negative locally integrable function on R^n and satisfies weak growth condition, a two-weight weak-type (p,q) inequality for TФ is obtained.展开更多
The speed of spread of Coronavirus Disease 2019 led to global lockdowns and disruptions in the academic sector.The study examined the impact of mobile technology on physics education during lockdowns.Data were collect...The speed of spread of Coronavirus Disease 2019 led to global lockdowns and disruptions in the academic sector.The study examined the impact of mobile technology on physics education during lockdowns.Data were collected through an online survey and later evaluated using regression tools,frequency,and an analysis of variance(ANOVA).The findings revealed that the usage of mobile technology had statistically significant effects on physics instructors’and students’academics during the coronavirus lockdown.Most of the participants admitted that the use of mobile technologies such as smartphones,laptops,PDAs,Zoom,mobile apps,etc.were very useful and helpful for continued education amid the pandemic restrictions.Online teaching is very effective during lock-down with smartphones and laptops on different platforms.The paper brings the limelight to the growing power of mobile technology solutions in physics education.展开更多
文摘Typically,a computer has infectivity as soon as it is infected.It is a reality that no antivirus programming can identify and eliminate all kinds of viruses,suggesting that infections would persevere on the Internet.To understand the dynamics of the virus propagation in a better way,a computer virus spread model with fuzzy parameters is presented in this work.It is assumed that all infected computers do not have the same contribution to the virus transmission process and each computer has a different degree of infectivity,which depends on the quantity of virus.Considering this,the parametersβandγbeing functions of the computer virus load,are considered fuzzy numbers.Using fuzzy theory helps us understand the spread of computer viruses more realistically as these parameters have fixed values in classical models.The essential features of the model,like reproduction number and equilibrium analysis,are discussed in fuzzy senses.Moreover,with fuzziness,two numerical methods,the forward Euler technique,and a nonstandard finite difference(NSFD)scheme,respectively,are developed and analyzed.In the evidence of the numerical simulations,the proposed NSFD method preserves the main features of the dynamic system.It can be considered a reliable tool to predict such types of solutions.
基金Supported by the National Natural Science Foundation of China (10671197)
文摘The Markov property of Markov process functionals which are frequently used in economy, finance, engineering and statistic analysis is studied. The conditions to judge Markov property of some important Markov process functionals are presented, the following conclusions are obtained: the multidimensional process with independent increments is a multidimensional Markov process; the functional in the form of path integral of process with independent increments is a Markov process; the surplus process with the doubly stochastic Poisson process is a vector Markov process. The conditions for linear transformation of vector Markov process being still a Markov process are given.
基金"Shu Guang"Plan of Education Committee of Shanghai (02SG32) Natural Science Foundation of ScienceCommittee of Shanghai(03ZR14071)
文摘Based on coupled-mode theo ry , the eigenvalue equation of five-layered long-period fiber grating(LPFG) sens or with Ag film and gas-sensitive film overlays are firstly studied. The probl em of resolving complex eigenvalue equation on five-layered LPFG is analyzed, a nd the method of resolution is also given. Then the eigenvalue equation of three -layered metal cladding LPFG is analyzed, and the complex transcendental equati on is also discussed. The computing result shows that the coupling between the l ow-order EH modes and the core mode is much stronger than that between the low -order HE modes and the core mode.
基金the National Natural Science Foundation of China (10771049 60773174)the Natural Science Foundation of Hebei Province (08M001)
文摘For the potential type operatorTФf(x)=∫RnФ(x-y)f(y)dy,where Ф is a non-negative locally integrable function on R^n and satisfies weak growth condition, a two-weight weak-type (p,q) inequality for TФ is obtained.
文摘The speed of spread of Coronavirus Disease 2019 led to global lockdowns and disruptions in the academic sector.The study examined the impact of mobile technology on physics education during lockdowns.Data were collected through an online survey and later evaluated using regression tools,frequency,and an analysis of variance(ANOVA).The findings revealed that the usage of mobile technology had statistically significant effects on physics instructors’and students’academics during the coronavirus lockdown.Most of the participants admitted that the use of mobile technologies such as smartphones,laptops,PDAs,Zoom,mobile apps,etc.were very useful and helpful for continued education amid the pandemic restrictions.Online teaching is very effective during lock-down with smartphones and laptops on different platforms.The paper brings the limelight to the growing power of mobile technology solutions in physics education.