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In this paper, we discuss two main problems. In the first section, we establish a new global distributed exact controllability of the periodic two-component μρ-Hunter-Saxton system on the circle by means of a distributed control. And in the second section, we present corresponding result of the as- ymptotic stabilization problem about the periodic two-component μρ-Hunter-Saxton system. By presenting concrete form of the feedback law, an equivalent system is got. [ABSTRACT FROM AUTHOR]

This paper establishes a nonlinear carbon cycle model based on the analysis of the carbon flux relationship among the atmosphere cycle, soil cycle and land cycle. By using nonlinear dynamics method, we examine the regional carbon cycle evolution along with the temporal evolution of the regional carbon flux. A neural network has been employed to identify the parameters of the proposed model, accordingly. In the numerical study, we propose the atmosphere-soil-land cycle model for Nanjing city of China. Then, the carbon cycle evolution of Nanjing has been simulated with the given model and actual data. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with a class of Schrödinger-Poisson systems with the asymptotically linear or asymptotically 3-linear nonlinearity. Under some suitable assumptions on V, K, a, and f, we prove the existence, nonexistence, and asymptotic behavior of solutions via variational methods. In particular, the potential V is allowed to be sign-changing for the asymptotically linear case. [ABSTRACT FROM AUTHOR]

We study the inelastic collision of two solitary waves of different velocities for the generalized Benjamin-Bona-Mahony (BBM) equation with cubic nonlinearity. It shows that one solitary wave is smaller than the other one in the H¹ (ℝ) energy space. We explore the sharp estimates of the nonzero residue due to the collision, and prove the inelastic collision of two solitary waves and nonexistence of a pure 2-soliton solution. [ABSTRACT FROM AUTHOR]

In this paper we build a ternary-tree real options investment decision model of Integrated Gasification Combined Cycle (IGCC) power plant's Carbon Capture and Storage(CCS) project based on the real options model and establish three key factors influencing the CCS project: CCS technical progresses, feed-in tariff and carbon permit trading. Effects of these factors on CCS are considered. Through a scenario analysis of CCS project investment decision with given parameters, the effects of fluctuation of these three key factors-variation coefficient of feed-in tariffs, coal fuel prices and CERs(Certified Emission Reduction) on CCS investment decision are further analyzed which indicates that this model can be applied to investment decisions of CCS. [ABSTRACT FROM AUTHOR]

When real networks are considered, coupled networks with connectivity and feedback-dependency links are not rare but more general. Here, we develop a mathematical framework and study numerically and analytically the percolation of interacting networks with feedback-dependency links. For the case that all degree distributions of intra- and inter- connectivity links are Poissonian, we find that for a low density of inter-connectivity links, the system undergoes from second order to first order through hybrid phase transition as coupling strength increases. It implies that the average degree k of inter-connectivity links has a little influence on robustness of the system with a weak coupling strength, which corresponds to the second order transition, but for a strong coupling strength corresponds to the first order transition. That is to say, the system becomes robust as k increases. However, as the average degree k of each network increases, the system becomes robust for any coupling strength. In addition, we find that one can take less cost to design robust system as coupling strength decreases by analyzing minimum average degree kmin of maintaining system stability. Moreover, for high density of inter-connectivity links, we find that the hybrid phase transition region disappears, the first order region becomes larger and second order region becomes smaller. For the case of two coupled scale-free networks, the system also undergoes from second order to first order through hybrid transition as the coupling strength increases. We find that for a weak coupling strength, which corresponds to the second order transitions, feedback dependency links have no effect on robustness of system relative to no-feedback condition, but for strong coupling strength which corresponds to first order or hybrid phase transition, the system is more vulnerable under feedback condition comparing with no-feedback condition. Thus, for designing resilient system, designers should try to avoid the feedback dependency links, because the existence of feedback- dependency links makes the system extremely vulnerable and difficult to defend. [ABSTRACT FROM AUTHOR]

In real world, most systems show significant clustering, and it is more practical to investigate the behaviors of clustered network. Previous studies are mostly focused on single clustered network and coupled clustered networks with dependency links. Here we study two clustered networks coupled with both interdependent and interconnected links by introducing generating function of the joint degree distribution. When the networks are fully dependent, we obtain the analytical solution of giant component P∞. We show rich phase transition phenomena and analyze their behaviors. We find that, as dependency coupling strength increases, the system changes from second order phase transition through hybrid transition to first order phase transition. For weak dependency coupling strength qA, corresponding to second order phase transition, we find that, clustering has almost no effect on the robustness of network, but for strong dependency coupling strength qA, corresponding to first order transition, the more clustered system is more vulnerable. At the same time, we notice that when the system is more clustered, the hybrid order region is almost unchangeable, the first order region becomes smaller, and the second order region is larger. Additionally, we can see that, the bigger the clustering coefficient c is, the bigger the second order region becomes. For the same c, the density of connectivity links between networks is higher, the second order region becomes smaller, and the density of connectivity links within each network is higher, the second order region becomes bigger. [ABSTRACT FROM AUTHOR]

The thermal stability of the standard Ni/SiC and a TiW/Ni/SiC Ohmic contacts was investigated and compared after being aged at 400 °C in the 2N2 atmosphere. The Ohmic contact was characterized using a combination of I-V measurements, the optical microscopic imaging, X-ray diffraction (XRD), and Auger electron spectroscopy (AES) techniques. It is shown that the standard Ni/SiC Ohmic contact failed after being aged at 400 °C for 20 h in the N2 atmosphere, while the TiW/Ni/SiC Ohmic contact could stand after 100 h. The TiW/Ni/SiC Ohmic contact was found kept a smooth surface morphology during the rapid thermal annealing and aging process, while the standard Ni/SiC Ohmic metal surface was found rougher. Both the Ohmic contact deteriorations after high temperature aging could be attributed to the formation of graphite which is confirmed by the XRD results. The XRD and AES results reveal that the better thermal stability of the TiW/Ni/SiC could be explained by the formation of CW3 and TiC, which deter the C atom diffusion to form graphite. [ABSTRACT FROM AUTHOR]

The dynamics of the nonlinear Schördinger equation with Kerr law nonlinearity with two perturbation terms are investigated. By Using Melnikov method, the threshold values of chaotic motion under periodic perturbation are given .Moreover we also study the effects of the parameters of system on dynamical behaviors by using numerical simulation. The numerical simulations, including bifurcation diagram of fixed points, chaos threshold diagram of system in three-dimensional space, maximum Lyapunov exponent, and phase portraits, are also plotted to illustrate theoretical analysis and to expose the complex dynamical behaviors. In particular, we observe that the system can leave chaotic region to periodic motion by adjusting controller e, amplitude d 1, and frequency ω2of external forcing which can be considered a control strategy, and when the frequencies y ω2 and ω1 approach the maximum frequency of disturbance, the system turmoil intensifies and control intensity increases. [ABSTRACT FROM AUTHOR]

The article focuses on a study conducted to understand the role of interdependence and independent networks. The authors studied the robustness of interdependent networks With partial support-dependence relationship. They also studied the Erdos-Renyi (ER) star-like networks developed by researchers Paul Erndos and Alfred Renyi. The article also mentions about system transformation from second-order through hybrid-order to first-order phase transition.

We report a new method for growing hexagonal columnar nanograin structured silicon carbide (SiC) thin films on silicon substrates by using graphene-graphitic carbon nanoflakes (GGNs) templates from solid carbon sources. The growth was carried out in a conventional low pressure chemical vapor deposition system (LPCVD). The GGNs are small plates with lateral sizes of around 100 nm and overlap each other, and are made up of nanosized multilayer graphene and graphitic carbon matrix (GCM). Long and straight SiC nanograins with hexagonal shapes, and with lateral sizes of around 200-400 nm are synthesized on the GGNs, which form compact SiC thin films. [ABSTRACT FROM AUTHOR]

We study the initial boundary value problem of the general three-component Camassa-Holm shallow water system on an interval subject to inhomogeneous boundary conditions. First we prove a local in time existence theorem and present a weak-strong uniqueness result. Then, we establish a asymptotic stabilization of this system by a boundary feedback. Finally, we obtain a result of blow-up solution with certain initial data and boundary profiles. [ABSTRACT FROM AUTHOR]

In underwater acoustic sensor networks (UASNs), the propagation delay of acoustic signals is much longer than Radio Frequency (RF). There is spatial unfairness problem caused by space-time uncertainty. Hence, the design of Medium Access Control (MAC) is a challenging issue. In underwater, it not only considers transmission time but also takes location into account. In this paper, we propose Response to the Earliest Transmitter of RTS MAC (RET-MAC) protocol to solve the problem. RET-MAC adopts adaptive RTS Contention Phase (RTS CP) to determine the earliest transmitter of RTS. And CTS Delay Phase (CTS DP) is added to postpone sending CTS in order to avoid collision. In addition, we propose CTS back-off mechanism to adjust the length of CTS DP as needed. Contention back-off mechanism is used to reduce network congestion and increase fairness further. The simulation results show that our scheme can achieve higher fairness and throughput; at the same time it also guarantees lower energy consumption and delay. [ABSTRACT FROM AUTHOR]

This paper studies the adaptive control problem of the Korteweg-de Vries-Burgers equation. Using the Lyapunov function method, we prove that the closed-loop system including the parameter estimator as a dynamic component is globally L2 stable. Furthermore, we show that the state of the system is regulated to zero by developing an alternative to Barbalat's lemma which cannot be used in the present situation. The closed-loop system is shown to be well posed. [ABSTRACT FROM AUTHOR]

We employ the bifurcation method of planar dynamical systems and qualitative theory of polynomial differential systems to derive new bounded traveling-wave solutions for a variant of the K(3, 2) equation. For the focusing branch, we obtain hump-shaped and valley-shaped solitary wave solutions and some periodic solutions. For the defocusing branch, the nonexistence of solitary traveling wave solutions is shown. Meanwhile, some periodic solutions are also obtained. The results presented in this paper supplement the previous results. [ABSTRACT FROM AUTHOR]

The Dullin–Gottwald–Holm equation can be described as the unidirectional propagation of surface waves in a shallow water regime. In this paper, we study the orbital stability problem of the peaked solitons (peakons) for the periodic Dullin–Gottwald–Holm equation on the line. By constructing a function only depending on three important conservative laws, we prove that the shapes of peakons are stable under small perturbations. We also demonstrate that the solutions of the Cauchy problem for this equation converge to those of the corresponding periodic Camassa–Holm equation as the linear dispersive parameter converges to zero. [ABSTRACT FROM AUTHOR]

This paper studies low-regularity solutions of the periodic Fornberg–Whitham equation with initial value. The existence and the uniqueness of solutions are proved. The results are illustrated by considering the periodic peakons of the periodic Fornberg–Whitham equation. [ABSTRACT FROM AUTHOR]

This paper is concerned with the global well posedness and limit behavior of the solutions to the viscous Degasperis–Procesi equation. We prove the global existence and uniqueness of solution to the viscous Degasperis–Procesi equation for u0∈L2(R). The local well posedness for u0∈L2(R) has been proven based on the energy estimate. The strong and weak limit behaviors of solution to the viscous Degasperis–Procesi equation are obtained. [ABSTRACT FROM AUTHOR]

Social interaction between individuals constantly affects the development of their personal opinions. Previous models such as the Deffuant model and the Hegselmann-Krause (HK) model have assumed that individuals only update their opinions after interacting with neighbors whose opinions are similar to their own. However, people are capable of communicating widely with all of their neighbors to gather their ideas and opinions, even if they encounter a number of opposing attitudes. We propose a model in which agents listen to the opinions of all their neighbors. Continuous opinion dynamics are investigated in activity-driven networks with a tolerance threshold. We study how the initial opinion distribution, tolerance threshold, opinion-updating speed, and activity rate affect the evolution of opinion. We find that when the initial fraction of positive opinion is small, all opinions become negative by the end of the simulation. As the initial fraction of positive opinions rises above a certain value —about 0.45— the final fraction of positive opinions sharply increases and eventually equals 1. Increased tolerance threshold δ is found to lead to a more varied final opinion distribution. We also find that if the negative opinion has an initial advantage, the final fraction of negative opinion increases and reaches its peak as the updating speed λ approaches 0.5. Finally we show that the lower the activity rate of individuals, the greater the fluctuation range of their opinions. [ABSTRACT FROM AUTHOR]

We study a system composed of two partially interdependent networks; when nodes in one network fail, they cause dependent nodes in the other network to also fail. In this paper, the percolation of partially interdependent networks under targeted attack is analyzed. We apply a general technique that maps a targeted-attack problem in interdependent networks to a random-attack problem in a transformed pair of interdependent networks. We illustrate our analytical solutions for two examples: (i) the probability for each node to fail is proportional to its degree, and (ii) each node has the same probability to fail in the initial time. We find the following: (i) For any targeted-attack problem, for the case of weak coupling, the system shows a second order phase transition, and for the strong coupling, the system shows a first order phase transition, (ii) For any coupling strength, when the high degree nodes have higher probability to fail, the system becomes more vulnerable, (iii) There exists a critical coupling strength, and when the coupling strength is greater than the critical coupling strength, the system shows a first order transition; otherwise, the system shows a second order transition. [ABSTRACT FROM AUTHOR]