The threat of malware in wireless sensor network has stimulated some activities to model and analyze the malware prevalence.To understand the dynamics of malware propagation in wireless sensor network,we propose a nov...The threat of malware in wireless sensor network has stimulated some activities to model and analyze the malware prevalence.To understand the dynamics of malware propagation in wireless sensor network,we propose a novel epidemic model named as e-SEIR(susceptible-exposed-infectious-recovered)model,which is a set of delayed differential equations,in this paper.The model has taken into account the following two factors:1 Multi-state antivirus measures;2 Temporary immune period.Then,the stability and Hopf bifurcation at the equilibria of linearized model are carefully analyzed by considering the distribution of eigenvalues of characteristic equations.Both mathematical analysis and numerical simulations show that the dynamical features of the proposed model rely on the basic reproduction number R0 and time delayτ.This novel model can help us to better understand and predict the propagation behaviors of malware in wireless sensor networks.展开更多
In the present paper,the cladistics method is used to analyze the phylogenetic relationship of 16 genera of Tinginae (Hemiptera:Heteroptera:Tingidae) from northern China. 33 characters with 88 states were chosen based...In the present paper,the cladistics method is used to analyze the phylogenetic relationship of 16 genera of Tinginae (Hemiptera:Heteroptera:Tingidae) from northern China. 33 characters with 88 states were chosen based on the morphological comparison. The character matrix was formed through ingroup and outgroup analysis and computed using the computer programs MacClad (version 3 0 1), AutoDecay (version 3 0), PAUP (version 3 1 1) and Hennig 86 (version 1 5),and the same most parsimonious tree and Nelson consensus cladogram were obtained from both computation to explain the phylogenetic relationship among the genera (L=118,CI=0 454,RI=0 529). We categorized these genera involved in the analysis phylogenetically into 6 groups according to the results. They are Agramma group,Leptoypha group,Dictyla group,Catoplatus group,Physatocheila group and Derephysia group. The phylogenetic relationship among the involved genera is presented as (((((Derephysia group=( Lasiacantha ,( Acalypta ,( Galeatus ,( Dictyonota ,( Derephysia,Sphaerista ))))),Physatocheila group =(( Elasmotropis,Tingis ),(( Oncochila,Cochlochila ), Physatocheila ))),Catoplatus group= Catoplatus ),Dictyla group=( Monosteira,Dictyla )),Leptoypha group= Leptoypha ),Agramma group= Agramma ). These groups will not be regarded as higher classific taxa until more genera and data are available and further analysis are carried out.展开更多
The solutions widely used at present for calculating complicated mine ventilation networks are ones in which resistance of the branches and characteristic parameters of the fans are taken as basic input data. But it i...The solutions widely used at present for calculating complicated mine ventilation networks are ones in which resistance of the branches and characteristic parameters of the fans are taken as basic input data. But it is time and energy consuming to obtain the branch resistance values. A new solution is developed in this paper in which the branch resistance values are obtained through measuring and evaluating the airflow of the whole ventilation network. Theoretical analysis is made of the establishment of a linear equation series with branch resistance as unknown numbers, an equation series for which one, and only one, result of solutions exists. This solution is programmed in C language and passed on a personal computer. The programmed solution programmed proves of practical use, as demonstrated by specific examples. Being different from other solutions, the method takes the branch airflow and fan working points as basic input data, and the present solution is of greater advantage for calculating ventilation networks of mines in operation.展开更多
基金National Natural Science Foundation of China(No.61379125)
文摘The threat of malware in wireless sensor network has stimulated some activities to model and analyze the malware prevalence.To understand the dynamics of malware propagation in wireless sensor network,we propose a novel epidemic model named as e-SEIR(susceptible-exposed-infectious-recovered)model,which is a set of delayed differential equations,in this paper.The model has taken into account the following two factors:1 Multi-state antivirus measures;2 Temporary immune period.Then,the stability and Hopf bifurcation at the equilibria of linearized model are carefully analyzed by considering the distribution of eigenvalues of characteristic equations.Both mathematical analysis and numerical simulations show that the dynamical features of the proposed model rely on the basic reproduction number R0 and time delayτ.This novel model can help us to better understand and predict the propagation behaviors of malware in wireless sensor networks.
文摘In the present paper,the cladistics method is used to analyze the phylogenetic relationship of 16 genera of Tinginae (Hemiptera:Heteroptera:Tingidae) from northern China. 33 characters with 88 states were chosen based on the morphological comparison. The character matrix was formed through ingroup and outgroup analysis and computed using the computer programs MacClad (version 3 0 1), AutoDecay (version 3 0), PAUP (version 3 1 1) and Hennig 86 (version 1 5),and the same most parsimonious tree and Nelson consensus cladogram were obtained from both computation to explain the phylogenetic relationship among the genera (L=118,CI=0 454,RI=0 529). We categorized these genera involved in the analysis phylogenetically into 6 groups according to the results. They are Agramma group,Leptoypha group,Dictyla group,Catoplatus group,Physatocheila group and Derephysia group. The phylogenetic relationship among the involved genera is presented as (((((Derephysia group=( Lasiacantha ,( Acalypta ,( Galeatus ,( Dictyonota ,( Derephysia,Sphaerista ))))),Physatocheila group =(( Elasmotropis,Tingis ),(( Oncochila,Cochlochila ), Physatocheila ))),Catoplatus group= Catoplatus ),Dictyla group=( Monosteira,Dictyla )),Leptoypha group= Leptoypha ),Agramma group= Agramma ). These groups will not be regarded as higher classific taxa until more genera and data are available and further analysis are carried out.
文摘The solutions widely used at present for calculating complicated mine ventilation networks are ones in which resistance of the branches and characteristic parameters of the fans are taken as basic input data. But it is time and energy consuming to obtain the branch resistance values. A new solution is developed in this paper in which the branch resistance values are obtained through measuring and evaluating the airflow of the whole ventilation network. Theoretical analysis is made of the establishment of a linear equation series with branch resistance as unknown numbers, an equation series for which one, and only one, result of solutions exists. This solution is programmed in C language and passed on a personal computer. The programmed solution programmed proves of practical use, as demonstrated by specific examples. Being different from other solutions, the method takes the branch airflow and fan working points as basic input data, and the present solution is of greater advantage for calculating ventilation networks of mines in operation.
