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In order to study traffic dynamics on multilayer networks, it is of great significance to build a network model which can more exactly reflect the actual network layered structure characteristics. In this paper, a three-layer network model in which two logical layers are mapped on one physical layer is established, and the traffic capacities of three kinds of multilayer networks with different combinations of logical layers are compared. Simulation results show that when the physical layer is the same random network, the network whose logical layers are two random networks has the optimal traffic capacity, the network with one random network and one scale-free network in the logical layers has the better traffic capacity than the network whose logical layers are two scale-free networks. [ABSTRACT FROM AUTHOR]

Traffic dynamics of multilayer networks draws continuous attention from different communities since many systems are actually proved to have a multilayer structure. Since the core nodes of network are prone to congested, an effective routing strategy is of great significance to alleviate the congestion of the multilayer networks. In this paper, we propose an efficient improved routing strategy, with which the core nodes that can reasonably avoid congestion at the high-speed layer in the transmission process of packets, and can also make the most of the traffic resources of the low-speed layer nodes to optimize the traffic capacity of multilayer networks. The simulation results show that the proposed routing strategy can not only improve the network traffic capacity, but also shorten the average path length and average transmission time. [ABSTRACT FROM AUTHOR]

The traffic dynamics of complex networks are largely determined by the node's resource distribution. In this paper, based on the shortest path routing strategy, a node delivering capacity distribution mechanism is proposed into the traffic dynamics in Barabási and Albert (BA) scale-free networks; the efficiency of the mechanism on the network capacity measured by the critical point ( R c ) of phase transition from free flow to congestion is primarily explored. Based on the proposed strategy, the total delivering capacity is reallocated according to both degree and betweenness of each node, and an optimal value of parameter α c is found, leading to the maximum traffic capacity. The results of numerical experiments on scale-free networks suggest that the resource allocation strategy proposed here is capable of effectively enhancing the transmission capacity of networks. Furthermore, this study may provide novel insights into research on networked traffic systems. [ABSTRACT FROM AUTHOR]

Modeling multiple complex systems as multiplex networks has refreshed our opinions about the structure and dynamics of assorted real-world systems. By studying the traffic dynamics of two-layer multiplex networks, it can be found that the limited buffer queue length of each node in both the logical and physical layers is one of the factors that restrict the whole network traffic capacity. Since high degree nodes in the network may bear heavier load, it is necessary to allocate a larger buffer queue to them. In order to enhance the transport efficiency, a new queue allocation strategy is proposed to alleviate the congestion of the two-layer multiplex networks. By extensive computer simulations, the proposed strategy can effectively improve the traffic capacity of the multiplex networks. [ABSTRACT FROM AUTHOR]

Based on the cognition of the physiological structure of the human visual system, this paper considers that the mechanism of the human visual system to perceive the image color appearance includes the adaptive mechanism of the retinal photoreceptor to the ambient light and the spatial frequency response mechanism of the Neuronal receptive field in the visual pathway. In this paper, we first provide the computing framework of the image color appearance model related to human cognitive process, then propose using Gabor wavelet as the basis function of the visual nerve cells response to apply CIECAT02 model to the calculation of image color adaption and to simulate the multi-scale superposition of human visual spatial frequency tuning curves, and finally accomplish the development of the algorithm for predicting image color appearance. The results show that the prediction algorithm proposed in this paper is closer to the visual perception of human eyes than the similar algorithm. [ABSTRACT FROM AUTHOR]

In recent years, the transportation systems have to face the increasing challenges of congestion and inefficiency, and therefore the research on traffic dynamics of complex networks has become a significant area. When the total node capacity of the network is fixed, a reasonable queue resource reallocation strategy is effective in improving the network traffic capacity. In this paper, a new queue resource allocation method is proposed based on the betweenness centrality and the degree centrality of nodes. With the proposed strategy, the node queue length is allocated accurately to enhance the transport efficiency. Simulation results show that the proposed strategy can effectively improve the traffic capacity of the scale-free networks. [ABSTRACT FROM AUTHOR]

Similar to auditory perception of sound system, color perception of the human visual system also presents a multi-frequency channel property. In order to study the multi-frequency channel mechanism of how the human visual system processes color information, the paper proposed a psychophysical experiment to measure the contrast sensitivities based on 17 color samples of 16 spatial frequencies on CIELAB opponent color space. Correlation analysis was carried out on the psychophysical experiment data, and the results show obvious linear correlations of observations for different spatial frequencies of different observers, which indicates that a linear model can be used to model how human visual system processes spatial frequency information. The results of solving the model based on the experiment data of color samples show that 9 spatial frequency tuning curves can exist in human visual system with each lightness, R–G and Y–B color channel and each channel can be represented by 3 tuning curves, which reflect the "center-around" form of the human visual receptive field. It is concluded that there are 9 spatial frequency channels in human vision system. The low frequency tuning curve of a narrow-frequency bandwidth shows the characteristics of lower level receptive field for human vision system, the medium frequency tuning curve shows a low pass property of the change of medium frequent colors and the high frequency tuning curve of a width-frequency bandwidth, which has a feedback effect on the low and medium frequency channels and shows the characteristics of higher level receptive field for human vision system, which represents the discrimination of details. [ABSTRACT FROM AUTHOR]

To investigate the dynamical load sharing behaviors of multi-floating components in the heavy load planetary gear system, a multi-floating planetary gear system that includes a floating central component and a quasi-floating planet flexible supporting pin is employed. Then a 21 degree of freedom lumped parameters dynamical model of this system is presented to study the dynamical load sharing behaviors. Some influencing factors, such as supporting stiffness, positions error of sun or carrier, and external input load are analyzed on the dynamical load sharing of the planetary gear system with multi-floating components. The results demonstrate that the load sharing condition of the system is best when both the sun gear and planet gears are multi-floating at the same time. When the planet gear position errors remain constant, reducing the flexible pin stiffness of planet gear or increasing external input load can effectively improve the load sharing. These conclusions are verified by the relevant experiments. [ABSTRACT FROM AUTHOR]

Based on the operating conditions of tablet PC, this paper presents the design of a long load life aluminum electrolytic capacitor. Due to the key technology breakthrough of electrolyte with low resistance and excellent temperature stability, the capacitor boasts low leakage current, low impedance, high frequency, high ripple resistance and high temperature resistance. In the meantime, it can pass 5000 h of durability test with load at 105C. The aluminum electrolytic capacitor can be used in tablet PC with long load life. [ABSTRACT FROM AUTHOR]

A dynamic model of gear transmission system which includes time-varying meshing stiffness, meshing damp and transmission error is established. Next, the analytical solution of the vibration response would be obtained by solving the dynamic model based on the harmonic balance method. And on this basis, a dynamic performance discrete optimization model of transmission sub-system would be constructed, which sets objective function up from vibration acceleration and the total mass of transmission sub-system, treats the module, number of teeth and helix angle as design variables, and takes gear strength and assembly relationship as constraints. Last, the optimal solution of design variables could be obtained through the multivariable mixed discrete optimization program which based on the branch-bound algorithm. The results show that the vibration acceleration and the total mass of transmission sub-system reduce by 34.6% and 6.8%, respectively. [ABSTRACT FROM AUTHOR]