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432. A new method to determine the sense of rotation of spiral arms in he barred galaxies
- Creator:
- Afanasiev, V. L., Fridman, A. M., and Pasha, I. I.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- spac eresearch, abrred galaxies, and spiral arms
- Language:
- Czech
- Description:
- Galactlc bars are thlcker than Inner parts of gas dlsks. Therefore gas flow Into theback side of bars, relatlve to the dlrectlon of dlsc rotation, Thls Idea, based on the equlllbrium condltlon for galactlc rotating subsystems Is used to Interprete forbldden line emlsslon In bar regione vhere gas Inflow supersonic. The suggested interpretation of the phenomenon of dlfferent velocity fields in the linea of dlfferent excltetion first discovered in the Seyfert galaxy Mkn 744 • NGC 3786 is now checked in the case of another Seyfert NGC 1068. .The appllcabillty Is controled from the Inferences concemlng the sense of rotation of spiral arms In the galaxies. In both cases these agree wlth the earlier results obtalned from Independent methods t the arms In NGC 1068 are trailling, while in NGC 3786 they are leadlng. One of manifestations of the shock back along the front slde of bars Is the occurence of stralght dust lanes along the front aide. Applications of the method to other observational problems are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
433. A New Multilayer Feedforward Network Based on Trimmed Mean Neuron Model
- Creator:
- Yolcu , Ufuk, Bas, Eren, Egrioglu, Erol , and Aladag, Cagdas Hakan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- neural networks, neuron model, trimmed mean, particle swarm optimization, outliers, and forecast
- Language:
- English
- Description:
- The multilayer perceptron model has been suggested as an alternative to conventional approaches, and can accurately forecast time series. Additionally, several novel artificial neural network models have been proposed as alternatives to the multilayer perceptron model, which have used (for example) the generalized- mean, geometric mean, and multiplicative neuron models. Although all of these artificial neural network models can produce successful forecasts, their aggregation functions mean that they are negatively affected by outliers. In this study, we propose a new multilayer, feed forward neural network model, which is a robust model that uses the trimmed mean neuron model. Its aggregation function does not depend on outliers. We trained this multilayer, feed forward neural network using modied particle swarm optimization. We applied the proposed method to three well-known time series, and our results suggest that it produces superior forecasts when compared with similar methods.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
434. A new neural design for faster pattern detection using cross correlation and matrix decomposition
- Creator:
- El-Bakry, Hazem M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Fast pattern detection, neural networks, cross correlation, frequency domain, image decomposition, sub-image normalization, and parallel processing
- Language:
- English
- Description:
- Neural networks have shown good results for detecting a certain pattern in a given image. In this paper, faster neural networks for pattern detection are presented. Such processors are designed based on cross correlation in the frequency domain between the input matrix and the input weights of neural networks. This approach is developed to reduce the computation steps required by these faster neural networks for the searching process. The principle of divide and conquer strategy is applied through matrix decomposition. Each matrix is divided into submatrices small in size, and then each one is tested separately by using a single faster neural processor. Furthermore, faster pattern detection is obtained by using parallel processing techniques to test the resulting submatrices at the same time, employing the same number of faster neural networks. In contrast to faster neural networks, the speed-up ratio is increased with the size of the input matrix when using faster neural networks and matrix decomposition. Moreover, the problem of local submatrix normalization in the frequency domain is solved. The effect of matrix normalization on the speed-up ratio of pattern detection is discussed. Simulation results show that local submatrix normalization through weight normalization is faster than submatrix normalization in the spatial domain. The overall speed-up ratio of the detection process is increased as the normalization of weights is done offline.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
435. A new numerical model for propagation of tsunami waves
- Creator:
- Švadlenka, Karel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- long waves, hyperbolic equation, volume constraint, free boundary, variational method, discrete Morse semi-flow, and FEM
- Language:
- English
- Description:
- A new model for propagation of long waves including the coastal area is introduced. This model considers only the motion of the surface of the sea under the condition of preservation of mass and the sea floor is inserted into the model as an obstacle to the motion. Thus we obtain a constrained hyperbolic free-boundary problem which is then solved numerically by a minimizing method called {\em the discrete Morse semi-flow}. The results of the computation in 1D show the adequacy of the proposed model.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
436. A new Nyquist-based technique for tuning robust decentralized controllers
- Creator:
- Kozáková, Alena, Veselý, and Osuský, Jakub
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- multivariable system, decentralized controller, frequency domain, independent design, robust stability, and unstructured uncertainty
- Language:
- English
- Description:
- An original Nyquist-based frequency domain robust decentralized controller (DC) design technique for robust stability and guaranteed nominal performance is proposed, applicable for continuous-time uncertain systems described by a set of transfer function matrices. To provide nominal performance, interactions are included in individual design using one selected characteristic locus of the interaction matrix, used to reshape frequency responses of decoupled subsystems; such modified subsystems are termed "equivalent subsystems". Local controllers of equivalent subsystems independently tuned for stability and specified feasible performance constitute the decentralized controller guaranteeing specified performance of the full system. To guarantee robust stability, the M−Δ stability conditions are derived. Unlike standard robust approaches, the proposed technique considers full nominal model, thus reducing conservativeness of resulting robust stability conditions. The developed frequency domain design procedure is graphical, interactive and insightful. A case study providing a step-by-step robust DC design for the Quadruple Tank Process [K.H. Johansson: Interaction bounds in multivariable control systems. Automatica 38 (2002), 1045-1051] is included.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
437. A new painting by Bartholomäus Spranger
- Creator:
- Fučíková, Eliška and Konečný, Lubomír
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
438. A new proof of a characterization of the set of all geodesics in a connected graph
- Creator:
- Nebeský, Ladislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- math, geodesics, and graphs
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
439. A New quantum particle swarm optimization algorithm with local attracting
- Creator:
- Shao, D., Hu, S., and Fei, Y.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- quantum particle swarm optimatization, quantum angle, and local attractor
- Language:
- English
- Description:
- This paper proposes a new quantum particle swarm optimization algorithm with local attracting (LAQPSO), which is based on quantum-inspired evolutionary algorithm (QEA) and particle swarm optimization algorithm (PSO). In the proposed LAQPSO, a novel quantum bit expression mechanism called quantum angle is employed to encode the solution onto particle, and a new local attractor is proposed to determine the rotation angle of quantum rotation gate automatically. During the process of seeking the global solution, the magnitude of rotation angle is adjusted by an important parameter called contraction coefficient, which can quantitatively determine the tradeoff between exploration ability and exploitation ability. The simulation results for different contraction coeffcients are helpful for selecting the key parameter. A set of benchmark functions are used to evaluate the performance of LAQPSO, QEA and QBPSO, and the results show that the proposed algorithm has a fast convergence rate and can effectively avoid premature convergence.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
440. A new regular multiplier embedding
- Creator:
- Bouza Allende, Gemayqzel and Guddat, Jürgen
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Jongen-Jonker-Twilt regularity, multipliers method, and embedding
- Language:
- English
- Description:
- Embedding approaches can be used for solving non linear programs \emph{P}. The idea is to define a one-parametric problem such that for some value of the parameter the corresponding problem is equivalent to \emph{P}. A particular case is the multipliers embedding, where the solutions of the corresponding parametric problem can be interpreted as the points computed by the multipliers method on \emph{P}. However, in the known cases, either path-following methods can not be applied or the necessary conditions for its convergence are fulfilled under very restrictive hypothesis. In this paper, we present a new multipliers embedding such that the objective function and the constraints of P(t) are C3 differentiable functions. We prove that the parametric problem satisfies the \emph{JJT}-regularity generically, a necessary condition for the success of the path-following method.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public