Let G be a simple graph with no isolated vertices. A set S of vertices of G is a total dominating set if every vertex of G is adjacent to some vertex in S . The total domination number of G , den...Let G be a simple graph with no isolated vertices. A set S of vertices of G is a total dominating set if every vertex of G is adjacent to some vertex in S . The total domination number of G , denoted by γ t (G) , is the minimum cardinality of a total dominating set of G . It is shown that if G is a graph of order n with minimum degree at least 3, then γ t (G)≤n/2 . Thus a conjecture of Favaron, Henning, Mynhart and Puech is settled in the affirmative.展开更多
By using a fixed point theorem on a cone to investigate the existence of two positive periodic solutions for the following delay difference system with feedback control argument of the form {△x（n）=-b（n）x（n）＋f...By using a fixed point theorem on a cone to investigate the existence of two positive periodic solutions for the following delay difference system with feedback control argument of the form {△x（n）=-b（n）x（n）＋f（n,x（n-τ1（n））,…,x（n-τm（n））,u（n-δ（n）））,△u（n）=-η（n）u（n）＋a（n）x（n-σ（n））,n∈Z.展开更多
Internet of things has been widely applied to industrial control, smart city and environmental protection, in these applica- tion scenarios, sensing node needs to make real-time response to the feedback control of the...Internet of things has been widely applied to industrial control, smart city and environmental protection, in these applica- tion scenarios, sensing node needs to make real-time response to the feedback control of the application layer. Therefore, it is nec- essary to monitor whether or not awareness nodes are trusted in real time, but the existing mechanisms for trusted certification lack the real-time measurement and tracking of the sensing node. To solve the above problems, this paper proposes a dynamic metric based authentication mechanism for sensing nodes of Internet of things. Firstly, the dynamic trustworthiness measure of the sensing nodes is carried out by introducing the computational function such as the trust function, the trust- worthiness risk assessment function, the feed- back control function and the active function of the sensing node. The dynamic trustworthi- ness measure of sensing nodes from multiple dimensions can effectively describe the change of trusted value of sensing nodes. Then, on the basis of this, a trusted attestation based on node trusted measure is realized by using the revocable group signature mechanism of local verifier. The mechanism has anonymity, un- forgeability and traceability, which is proved the security in the standard model. Simulationexperiments show that the proposed trusted attestation mechanism is flexible, practical and ef｜Scient and has better attack resistance. It can effectively guarantee the reliable data transmission of nodes and realize the dynamic tracking of node reliability, which has a lower impact on system performance.展开更多
Synthetic aperture radar interferometry (InSAR) has been used as an innovative technique for digital elevation model (DEM) and topographic map generation. In this paper, external DEMs are used for InSAR DEM generation...Synthetic aperture radar interferometry (InSAR) has been used as an innovative technique for digital elevation model (DEM) and topographic map generation. In this paper, external DEMs are used for InSAR DEM generation to reduce the errors in data processing. The DEMs generated from repeat-pass InSAR are compared. For steep slopes and severe changes in topography, phase unwrapping quality can be improved by subtracting the phase calculated from an external DEM. It is affirmative that the absolute height accuracy of the InSAR DEM is improved by using external DEM. The data processing was undertaken without the use of ground control points and other manual operation.展开更多
In this paper, we introduce a new combined priority and admission control mechanism applying in the VCN （Vehicular Communication Network） which is designed with an integration of the Vehicular Ad-hoc Networks （VAN...In this paper, we introduce a new combined priority and admission control mechanism applying in the VCN （Vehicular Communication Network） which is designed with an integration of the Vehicular Ad-hoc Networks （VANETs） based on standard IEEE 802.11 p and IEEE 802.11 s WMNs （Wireless Mesh Networks）. Simulation experiments are intensively investigated to evaluate the novel combined priority and admission control mechanism to assure quality of the I2V （Infrastructure to Vehicle） emergency services occurred during the time video flows are being delivered between content servers and cars. The simulation results show effectiveness of proposed priority and admission control schemes in term of the minimized end-to-end delay as well as the increase of throughput and PDR （Packet Delivery Ratio） of the emergency data flow.展开更多
Aiming at the difficulty of setting the weight coefficient in the value function of model predictive torque control(MPTC)for permanent magnet synchronous motor(PMSM)driven by three-level inverter,a fine-division model...Aiming at the difficulty of setting the weight coefficient in the value function of model predictive torque control(MPTC)for permanent magnet synchronous motor(PMSM)driven by three-level inverter,a fine-division model predictive flux control(MPFC)method is proposed.First,establish a mathematical model between the motor torque and the stator flux linkage according to the mathematical equations of PMSM.Thus,the control of the motor torque and stator flux linkage in the MPTC is transformed into the control of a single stator flux linkage vector,omitting the cumbersome weight setting process in the traditional MPTC.The midpoint potential control strategy is proposed,which uses the characteristics of redundant small vectors to balance the midpoint potential.After that,a fine-division strategy is proposed,which effectively reduces the number of candidate vectors and the computational burden of the system.Finally,the proposed MPFC is compared with MPTC by simulation.The results show that the proposed fine-division MPFC effectively reduces the system calculation,and has the advantages of simple principle and better dynamic and steady-state control performance.The feasibility of the control strategy is verified.展开更多
Keeping balance is the premise of human walking. ZMP(zero moment point) is a point where total torque achieves balance. It is an important evaluation parameter of balance ability in walking, since it can be used to be...Keeping balance is the premise of human walking. ZMP(zero moment point) is a point where total torque achieves balance. It is an important evaluation parameter of balance ability in walking, since it can be used to better reflect the dynamic balance during walking. ZMP can be used in many applications, such as medical rehabilitation, disease diagnosis, treatment and etc. In this paper, wearable inertial sensors system based on MEMS is used to measure ZMP(zero moment point) during walking, which is cheap, convenient, and free from the restriction of lab. Our wearable ZMP measurement system consists of inertial measurement subsystem and PC real-time monitoring station. Inertial measurement subsystem includes 9-axis inertial sensing nodes, the body communication network and the central node. Inertial sensing nodes are mounted on different parts of the body to collect body posture information in real-time, and then the best estimation of current posture are obtained by Kalman filter. The data from sensors is aggregated to the central node through the CAN bus, and then ZMP is calculated. Finally, it can be showed in the PC monitoring station. Experiments prove the system can achieve real-time ZMP detection during walking.展开更多
In this paper,the control of complex delayed networks with different nodes is proposed.Firstly,the stabilization of coupled networks with time delay is investigated.By constructing a Lyapunov function,a linear feedbac...In this paper,the control of complex delayed networks with different nodes is proposed.Firstly,the stabilization of coupled networks with time delay is investigated.By constructing a Lyapunov function,a linear feedback controller design procedure for the networks is converted to the problem of solving a set of linear matrix inequalities.Then the results are extended to networks with both delayed dynamical nodes and delayed couplings.It is shown that the stabilization of complex networks is determined by the dynamics of each uncoupled node,coupling matrix and feedback gain matrix of networks.Two examples are simulated.In the first example,a network with 10 nodes consisting of Lorenz systems and systems proposed by Zhang in 2009 is given.It is found that the network states are divergent without control,and convergent under designed linear feedback controllers.In the second example,a larger network with 100 nodes consisting of delayed Chen systems and delayed Lorenz systems is given.The proposed method is also effective for large scale networks.展开更多
We have introduced the total domination polynomial for any simple non isolated graph G in [7] and is defined by Dt（G, x） = ∑in=yt（G） dr（G, i） x＇, where dr（G, i） is the cardinality of total dominating sets of...We have introduced the total domination polynomial for any simple non isolated graph G in [7] and is defined by Dt（G, x） = ∑in=yt（G） dr（G, i） x＇, where dr（G, i） is the cardinality of total dominating sets of G of size i, and yt（G） is the total domination number of G. In [7] We have obtained some properties of Dt（G, x） and its coefficients. Also, we have calculated the total domination polynomials of complete graph, complete bipartite graph, join of two graphs and a graph consisting of disjoint components. In this paper, we presented for any two isomorphic graphs the total domination polynomials are same, but the converse is not true. Also, we proved that for any n vertex transitive graph of order n and for any v ∈ V（G）, dt（G, i） = 7 dt（V）（G, i）, 1 〈 i 〈 n. And, for any k-regular graph of order n, dr（G, i） = （7）, i 〉 n-k and d,（G, n-k） = （kn） - n. We have calculated the total domination polynomial of Petersen graph D,（P, x） = 10X4 ＋ 72x5 ＋ 140x6 ＋ 110x7 ＋ 45x8 ＋ [ 0x9 ＋ x10. Also, for any two vertices u and v of a k-regular graph Hwith N（u） ≠ N（v） and if Dr（G, x） = Dt（ H, x ）, then G is also a k-regular graph.展开更多
A vertex of a graph is said to dominate itself and all of its neighbors. A double dominating set of a graph G is a set D of vertices of G, such that every vertex of G is dominated by at least two vertices of D. The do...A vertex of a graph is said to dominate itself and all of its neighbors. A double dominating set of a graph G is a set D of vertices of G, such that every vertex of G is dominated by at least two vertices of D. The double domination number of a graph G is the minimum cardinality of a double dominating set of G. For a graph G = （V, E）, a subset D C V（G） is a 2-dominating set if every vertex of V（G） ／ D has at least two neighbors in D, while it is a 2-outer-independent dominating set of G if additionally the set V（G）／D is independent. The 2-outer-independent domination number of G is the minimum cardinality of a 2-outer-independent dominating set of G. This paper characterizes all trees with the double domination number equal to the 2-outer-independent domination number plus one.展开更多
In this paper, by means of Sadovskii fixed point theorem, the authors establish a result concerning the controllability for a class of abstract neutral functional differential systems where the linear part is non-dens...In this paper, by means of Sadovskii fixed point theorem, the authors establish a result concerning the controllability for a class of abstract neutral functional differential systems where the linear part is non-densely defined and satisfies the Hille-Yosida condition. As an application, an example is provided to illustrate the obtained result.展开更多
文摘Let G be a simple graph with no isolated vertices. A set S of vertices of G is a total dominating set if every vertex of G is adjacent to some vertex in S . The total domination number of G , denoted by γ t (G) , is the minimum cardinality of a total dominating set of G . It is shown that if G is a graph of order n with minimum degree at least 3, then γ t (G)≤n/2 . Thus a conjecture of Favaron, Henning, Mynhart and Puech is settled in the affirmative.
基金Supported by the National Natural Sciences Foundation of China(10361006)Supported by the Natural Sciences Foundation of Yunnan Province(2003A0001M)Supported by the Jiangsu "Qing-lanProject" for Excellent Young Teachers in University(2006)
文摘By using a fixed point theorem on a cone to investigate the existence of two positive periodic solutions for the following delay difference system with feedback control argument of the form {△x（n）=-b（n）x（n）＋f（n,x（n-τ1（n））,…,x（n-τm（n））,u（n-δ（n）））,△u（n）=-η（n）u（n）＋a（n）x（n-σ（n））,n∈Z.
基金supported by the National Natural Science Foundation of China (The key trusted running technologies for the sensing nodes in Internet of things: 61501007, The research of the trusted and security environment for high energy physics scientific computing system: 11675199)General Project of science and technology project of Beijing Municipal Education Commission: KM201610005023+2 种基金the outstanding personnel training program of Beijing municipal Party Committee Organization Department (The Research of Trusted Computing environment for Internet of things in Smart City: 2014000020124G041)The key technology research and validation issue for the emergency treatment telemedicine public service platform which integrates the military and civilian and bases on the broadband wireless networks (No.2013ZX03006001-005)the issue belongs to Major national science and technology projects
文摘Internet of things has been widely applied to industrial control, smart city and environmental protection, in these applica- tion scenarios, sensing node needs to make real-time response to the feedback control of the application layer. Therefore, it is nec- essary to monitor whether or not awareness nodes are trusted in real time, but the existing mechanisms for trusted certification lack the real-time measurement and tracking of the sensing node. To solve the above problems, this paper proposes a dynamic metric based authentication mechanism for sensing nodes of Internet of things. Firstly, the dynamic trustworthiness measure of the sensing nodes is carried out by introducing the computational function such as the trust function, the trust- worthiness risk assessment function, the feed- back control function and the active function of the sensing node. The dynamic trustworthi- ness measure of sensing nodes from multiple dimensions can effectively describe the change of trusted value of sensing nodes. Then, on the basis of this, a trusted attestation based on node trusted measure is realized by using the revocable group signature mechanism of local verifier. The mechanism has anonymity, un- forgeability and traceability, which is proved the security in the standard model. Simulationexperiments show that the proposed trusted attestation mechanism is flexible, practical and ef｜Scient and has better attack resistance. It can effectively guarantee the reliable data transmission of nodes and realize the dynamic tracking of node reliability, which has a lower impact on system performance.
基金Funded by the Key Tenth five Project of State Bureau of Surveying and Mapping (No. 1469990324236 04 06) and the Faculty Research Grant of Uni versity of New South Wales (No. PS03283).
文摘Synthetic aperture radar interferometry (InSAR) has been used as an innovative technique for digital elevation model (DEM) and topographic map generation. In this paper, external DEMs are used for InSAR DEM generation to reduce the errors in data processing. The DEMs generated from repeat-pass InSAR are compared. For steep slopes and severe changes in topography, phase unwrapping quality can be improved by subtracting the phase calculated from an external DEM. It is affirmative that the absolute height accuracy of the InSAR DEM is improved by using external DEM. The data processing was undertaken without the use of ground control points and other manual operation.
文摘In this paper, we introduce a new combined priority and admission control mechanism applying in the VCN （Vehicular Communication Network） which is designed with an integration of the Vehicular Ad-hoc Networks （VANETs） based on standard IEEE 802.11 p and IEEE 802.11 s WMNs （Wireless Mesh Networks）. Simulation experiments are intensively investigated to evaluate the novel combined priority and admission control mechanism to assure quality of the I2V （Infrastructure to Vehicle） emergency services occurred during the time video flows are being delivered between content servers and cars. The simulation results show effectiveness of proposed priority and admission control schemes in term of the minimized end-to-end delay as well as the increase of throughput and PDR （Packet Delivery Ratio） of the emergency data flow.
基金National Natural Science Foundation of China(No.51867012)。
文摘Aiming at the difficulty of setting the weight coefficient in the value function of model predictive torque control(MPTC)for permanent magnet synchronous motor(PMSM)driven by three-level inverter,a fine-division model predictive flux control(MPFC)method is proposed.First,establish a mathematical model between the motor torque and the stator flux linkage according to the mathematical equations of PMSM.Thus,the control of the motor torque and stator flux linkage in the MPTC is transformed into the control of a single stator flux linkage vector,omitting the cumbersome weight setting process in the traditional MPTC.The midpoint potential control strategy is proposed,which uses the characteristics of redundant small vectors to balance the midpoint potential.After that,a fine-division strategy is proposed,which effectively reduces the number of candidate vectors and the computational burden of the system.Finally,the proposed MPFC is compared with MPTC by simulation.The results show that the proposed fine-division MPFC effectively reduces the system calculation,and has the advantages of simple principle and better dynamic and steady-state control performance.The feasibility of the control strategy is verified.
基金supported by "the Fundamental Research Funds for the Central Universities" ZYGX2013J123
文摘Keeping balance is the premise of human walking. ZMP(zero moment point) is a point where total torque achieves balance. It is an important evaluation parameter of balance ability in walking, since it can be used to better reflect the dynamic balance during walking. ZMP can be used in many applications, such as medical rehabilitation, disease diagnosis, treatment and etc. In this paper, wearable inertial sensors system based on MEMS is used to measure ZMP(zero moment point) during walking, which is cheap, convenient, and free from the restriction of lab. Our wearable ZMP measurement system consists of inertial measurement subsystem and PC real-time monitoring station. Inertial measurement subsystem includes 9-axis inertial sensing nodes, the body communication network and the central node. Inertial sensing nodes are mounted on different parts of the body to collect body posture information in real-time, and then the best estimation of current posture are obtained by Kalman filter. The data from sensors is aggregated to the central node through the CAN bus, and then ZMP is calculated. Finally, it can be showed in the PC monitoring station. Experiments prove the system can achieve real-time ZMP detection during walking.
基金Supported by National Natural Science Foundation of China (No.61004015)Research Fund for the Doctoral Program of Higher Education of China (No.20090032120034)
文摘In this paper,the control of complex delayed networks with different nodes is proposed.Firstly,the stabilization of coupled networks with time delay is investigated.By constructing a Lyapunov function,a linear feedback controller design procedure for the networks is converted to the problem of solving a set of linear matrix inequalities.Then the results are extended to networks with both delayed dynamical nodes and delayed couplings.It is shown that the stabilization of complex networks is determined by the dynamics of each uncoupled node,coupling matrix and feedback gain matrix of networks.Two examples are simulated.In the first example,a network with 10 nodes consisting of Lorenz systems and systems proposed by Zhang in 2009 is given.It is found that the network states are divergent without control,and convergent under designed linear feedback controllers.In the second example,a larger network with 100 nodes consisting of delayed Chen systems and delayed Lorenz systems is given.The proposed method is also effective for large scale networks.
文摘We have introduced the total domination polynomial for any simple non isolated graph G in [7] and is defined by Dt（G, x） = ∑in=yt（G） dr（G, i） x＇, where dr（G, i） is the cardinality of total dominating sets of G of size i, and yt（G） is the total domination number of G. In [7] We have obtained some properties of Dt（G, x） and its coefficients. Also, we have calculated the total domination polynomials of complete graph, complete bipartite graph, join of two graphs and a graph consisting of disjoint components. In this paper, we presented for any two isomorphic graphs the total domination polynomials are same, but the converse is not true. Also, we proved that for any n vertex transitive graph of order n and for any v ∈ V（G）, dt（G, i） = 7 dt（V）（G, i）, 1 〈 i 〈 n. And, for any k-regular graph of order n, dr（G, i） = （7）, i 〉 n-k and d,（G, n-k） = （kn） - n. We have calculated the total domination polynomial of Petersen graph D,（P, x） = 10X4 ＋ 72x5 ＋ 140x6 ＋ 110x7 ＋ 45x8 ＋ [ 0x9 ＋ x10. Also, for any two vertices u and v of a k-regular graph Hwith N（u） ≠ N（v） and if Dr（G, x） = Dt（ H, x ）, then G is also a k-regular graph.
文摘A vertex of a graph is said to dominate itself and all of its neighbors. A double dominating set of a graph G is a set D of vertices of G, such that every vertex of G is dominated by at least two vertices of D. The double domination number of a graph G is the minimum cardinality of a double dominating set of G. For a graph G = （V, E）, a subset D C V（G） is a 2-dominating set if every vertex of V（G） ／ D has at least two neighbors in D, while it is a 2-outer-independent dominating set of G if additionally the set V（G）／D is independent. The 2-outer-independent domination number of G is the minimum cardinality of a 2-outer-independent dominating set of G. This paper characterizes all trees with the double domination number equal to the 2-outer-independent domination number plus one.
基金Project supported by the Tianyuan Foundation of Mathematics (No. A0324624)the National Natural Science Founcation of China (No. 10371040)the Shanghai Priority Academic Discipline.
文摘In this paper, by means of Sadovskii fixed point theorem, the authors establish a result concerning the controllability for a class of abstract neutral functional differential systems where the linear part is non-densely defined and satisfies the Hille-Yosida condition. As an application, an example is provided to illustrate the obtained result.
