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522. A novel algorithm for the modeling of complex processes
- Creator:
- Rubio, José de Jesús, Lughofer, Edwin, Angelov, Plamen, Novoa, Juan Francisco, and Meda-Campaña, Jesús A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- recursive least square, Kalman filter, modeling, and complex processes
- Language:
- English
- Description:
- In this investigation, a new algorithm is developed for the updating of a neural network. It is concentrated in a fuzzy transition between the recursive least square and extended Kalman filter algorithms with the purpose to get a bounded gain such that a satisfactory modeling could be maintained. The advised algorithm has the advantage compared with the mentioned methods that it eludes the excessive increasing or decreasing of its gain. The gain of the recommended algorithm is uniformly stable and its convergence is found. The new algorithm is employed for the modeling of two synthetic examples.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
523. A novel approach to modelling of flow in fractured porous medium
- Creator:
- Šembera, Jan, Maryška, Jiří, Královcová, Jiřina, and Severýn, Otto
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- finite element method, Darcy´s flow, and fractured porous medium
- Language:
- English
- Description:
- There are many problems of groundwater flow in a disrupted rock massifs that should be modelled using numerical models. It can be done via "standard approaches'' such as increase of the permeability of the porous medium to account the fracture system (or double-porosity models), or discrete stochastic fracture network models. Both of these approaches appear to have their constraints and limitations, which make them unsuitable for the large-scale long-time hydrogeological calculations. In the article, a new approach to the modelling of groudwater flow in fractured porous medium, which combines the above-mentioned models, is described. This article presents the mathematical formulation and demonstration of numerical results obtained by this new approach. The approach considers three substantial types of objects within a structure of modelled massif important for the groudwater flow - small stochastic fractures, large deterministic fractures, and lines of intersection of the large fractures. The systems of stochastic fractures are represented by blocks of porous medium with suitably set hydraulic conductivity. The large fractures are represented as polygons placed in 3D space and their intersections are represented by lines. Thus flow in 3D porous medium, flow in 2D and 1D fracture systems, and communication among these three systems are modelled together.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
524. A Novel attribute-based access control model for multimedia social networks
- Creator:
- Zhang, Z., Han, L., Li, C., and Wang, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- multimedia social networks, attribute-based acces control, security, and prototype
- Language:
- English
- Description:
- Multimedia social networks (MSNs) provide great convenience to users, while privacy leaks issues are becoming prominent. The studies on relationship-based access control have been widely used in social networks. However, with the dynamic development of social networks and rapid growth of user information, the access control does not completely meet the current system's need. In this paper, an attribute-based access control model called ABAC{MSN is proposed for MSNs. This model comprehensively considers user attributes, environment attributes and resource attributes, not only including relationships among users. In this model, users can set multimedia usage control policies based on three categories of user-defined attributes. A formal theoretical model is established, which includes constraint rules, data ow rules, policy conflict resolution mechanism, and applied to CyVOD.net, a multimedia social-network-platform prototype systems. The deployment and application denote that this method effectively and exibly addresses use-case scenarios of multi-attribute-based media access control, and improves the access security of social media platforms and resources.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
525. A Novel Framework to Alleviate Dissemination of XSS Worms in Online Social Network (OSN) using View Segregation
- Creator:
- Chaudhary, P. and Gupta, B. B.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Cross-Site Scripting (XSS) worms, online social network security, and URI links
- Language:
- English
- Description:
- In this paper, we propose a client-server based framework that alleviates the dissemination of XSS worms from the OSN. The framework initially creates the views corresponding to retrieved request on the server-side. Such views indicate that which part of the generated web page on the server can be accessed by user depending on the generated Access Control List (ACL). Secondly, JavaScript attack vectors are retrieved from the HTTP response by referring the blacklist repository of attack vectors. Finally, injection of sanitization primitives will be done on the client-side in place of extracted JavaScript attack vectors. The framework will perform the sanitization on such attack vectors strictly in a context-aware manner. The experimental testing of our framework has performed on the two platforms of open source OSN-based web applications. The observed detection rate of JavaScript attack vectors was effective and acceptable as compared to other existing XSS defensive methodologies. The proposed framework has optimized the method of auto-context-aware sanitization in contrast to other existing approaches and hence incurs a low and acceptable performance overhead.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
526. A novel LMI-based robust model predictive control for DFIG-based wind energy conversion systems
- Creator:
- Gholami, Amir , Sahab, Alireza , Tavakoli , Abdolreza , and Alizadeh, Behnam
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- linear matrix inequality, optimization, robust model predictive control, doubly fed induction generator, and active and reactive power
- Language:
- English
- Description:
- The optimal and reliable performance of doubly fed induction generator is essential for the efficient and optimal operation of wind energy conversion systems. This paper considers the nonlinear dynamic of a DFIG linked to a power grid and presents a new robust model predictive control technique of active and reactive power by the use of the linear matrix inequality in DFIG-based WECS. The control law is obtained through the LMI-based model predictive control that allows considering both economic and tracking factors by optimization of an objective function, constraints on control signal and states of system and effects of nonlinearities, generator parameter uncertainties and external disturbances. Robust stability in the face of bounded disturbances and generator uncertainty is shown using Lyapunov technique. Numerical simulations show that the proposed control method is able to meet the desired specification in active and reactive power control in the presence of varieties of wind speed and pitch angle.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
527. A novel neuroregenerative approach using ETB receptor agonist, IRL-1620, to treat CNS disorders
- Creator:
- Gulati, A., Hornick, M. G., Lavhale, M. S., and Briyal, S.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fyziologie člověka, human physiology, Endothelin, ETB receptors, Neuroregeneration, Alzheimer’s disease, Ischemic stroke, Amyotrophic lateral sclerosis, 14, and 612
- Language:
- English
- Description:
- Endothelin B (ETB) receptors present in abundance the central nervous system (CNS) have been shown to have significant implications in its development and neurogenesis. We have targeted ETB receptors stimulation using a highly specific agonist, IRL-1620, to treat CNS disorders. In a rat model of cerebral ischemia intravenous administration IRL-1620 significantly reduced infarct volume and improved neurological and motor functions compared to control. This improvement, in part, is due to an increase in neuroregeneration. We also investigated the role of IRL-1620 in animal models of Alzheimer’s disease (AD). IRL-1620 improved learning and memory, reduced oxidative stress and increased VEGF and NGF in Aβ treated rats. IRL-1620 also improved learning and memory in an aged APP/PS1 transgenic mouse model of AD. These promising findings prompted us to initiate human studies. Successful chemistry, manufacturing and control along with mice, rat and dog toxicological studies led to completion of a human Phase I study in healthy volunteers. We found that a dose of 0.6 μg/kg of IRL-1620 can be safely administered, three times every four hours, without any adverse effect. A Phase II clinical study with IRL-1620 has been initiated in patients with cerebral ischemia and mild to moderate AD., A. Gulati, M. G. Hornick, S. Briyal, M. S. Lavhale., and Seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
528. A novel spiking perceptron that can solve XOR problem
- Creator:
- Yang, Jie, Yang, Wenyu, and Wu, Wei
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Spiking perceptron, firing time, spiking intensity, and XOR problem
- Language:
- English
- Description:
- In this short note, we introduce a new architecture for spiking perceptron: The actual output is a linear combination of the firing time of the perceptron and the spiking intensity (the gradient of the state function) at the firing time. It is shown by numerical experiments that this novel spiking perceptron can solve the XOR problem, while a classical spiking neuron usually needs a hidden layer to solve the XOR problem.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
529. A numerical study of Newton interpolation with extremely high degrees
- Creator:
- Breuss, Michael, Kemm, Friedemann, and Vogel, Oliver
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- polynomial interpolation, Newton interpolation, interpolation nodes, Chebyshev nodes, Leja ordering, and fast Leja points
- Language:
- English
- Description:
- In current textbooks the use of Chebyshev nodes with Newton interpolation is advocated as the most efficient numerical interpolation method in terms of approximation accuracy and computational effort. However, we show numerically that the approximation quality obtained by Newton interpolation with Fast Leja (FL) points is competitive to the use of Chebyshev nodes, even for extremely high degree interpolation. This is an experimental account of the analytic result that the limit distribution of FL points and Chebyshev nodes is the same when letting the number of points go to infinity. Since the FL construction is easy to perform and allows to add interpolation nodes on the fly in contrast to the use of Chebyshev nodes, our study suggests that Newton interpolation with FL points is currently the most efficient numerical technique for polynomial interpolation. Moreover, we give numerical evidence that any reasonable function can be approximated up to machine accuracy by Newton interpolation with FL points if desired, which shows the potential of this method.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
530. A numerical study of resonances in collisional disks: application to planetary ring area
- Creator:
- Sicardy, Bruno
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- space research, planetary rings, and collisions
- Language:
- Czech
- Description:
- Many recent observations have shown that resonances have a wide variety of effects in planetary rings: spiral waves, gaps, confinement, sharp edges, arcs. While resonances are known to be associated with such structures, the role of inter-particle collisions is still poorly understood, although necessary to explain the long term evolution of the rings. In an effort to better understand the associated dynamics, we have performed numerical simulations of colliding particles orbiting a massive central planet. The code simulates the 3-D motion of 100 identical spherical particles orbiting a massive cental body and suffering inelastic collisions while being perturbed by one or more satellites. We used this code to explore in more details the dynamics of are rings, and to explain in particular the reeent observations of are structures around Neptune. Clusters of particles at a satellite’s Lagrangian point {L4 or L5) are shown to be dispersed by dissipative effects. However, a second satellite can stabilize the system by providing sufficient energy through a Lindblaďs resonance m±l:m. Other dynamically equivalent configurations (e.g. only one satellite, but with an eccentric orbit) can also stabilize are sytems, in accord with current analytical models. We examine the roles of collisions at Lindblad and corotation resonances in various cases. Arcs remain at the potential maxima created by the corotations. However, stability requires that the satellites’ masses be within a limited range: small satellites cannot provide enough energy while large ones give too much, so the arc can disperse.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public