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822. 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
823. A new model for relationship between irradiance and the rate of photosynthesis in Oryza sativa
- Creator:
- Ye, Z.-P.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- apparent quantum yield, compensation irradiance, intrinsic quantum yield, and saturation irradiance
- Language:
- Multiple languages
- Description:
- The calculated maximum net photosynthetic rate (PN) at saturation irradiance (I m) of 1 314.13 µmol m-2 s-1 was 25.49 µmol(CO2) m-2 s-1, and intrinsic quantum yield at zero irradiance was 0.103. The results fitted by nonrectangular hyperbolic model, rectangular hyperbolic method, binomial regression method, and the new model were compared. The maximum PN values calculated by nonrectangular hyperbolic model and rectangular hyperbolic model were higher than the measured values, and the I m calculated by nonrectangular hyperbolic model and rectangular hyperbolic model were less than measured values. Results fitted by new model showed that the response curve of PN to I was nonlinear at low I for Oryza sativa, PN increased nonlinearly with I below saturation value. Above this value, PN decreased nonlinearly with I.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
824. A new monorchiid cercaria (Digenea) parasitising the purple clam Amiantis purpurata (Bivalvia: Veneridae) in the Southwest Atlantic Ocean, with notes on its gonadal effect
- Creator:
- Cremonte, Florencia, Kroeck, Marina Andrea, and Martorelli, Sergio Roberto
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Digenea, Monorchiidae, cercaria, metacercaria, Bivalvia, Veneridae, and Argentine Sea
- Language:
- English
- Description:
- An unnamed microcercous cercaria (Digenea: Monorchiidae), a parasite of Amiantis purpurata (Lamarck, 1818) (Bivalvia: Veneridae) and its corresponding metacercaria from the province of Buenos Aires and the Patagonian coast of the Southwest Atlantic Ocean, are described. The cercaria described in this paper differs from the three other monorchiid microcercous cercariae, i.e., Lasiotocus minutus (Manter, 1931), Lasiotocus elongatus (Manter, 1931), and Cercaria caribbea XXXVI Cable, 1956, mainly because of the extension of the excretory vesicle and the location of the ventral sucker. Cercariae artificially extracted from sporocysts encyst in a dish and form metacercariae enveloped by a gelatinous sac with two prolongations, which are used to adhere to the substratum. The monorchiid described in this paper has a life cycle similar to those of L. minutus and L. elongatus, although the adult stage of the present species is still unknown. Their larvae are similar in morphology and have venerid clams as their first hosts. The presence of a monorchiid larva is reported for the first time in the Southern Hemisphere. Its monthly prevalence rates, ranging from 0 to 25% (mean: 8.3%), are given from the Patagonian coast. The infection seems to cause castration as it was observed that during March through to May, when most gametes were produced in uninfected individuals, 81% of the infected individuals did not produce gametes.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
825. 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
826. 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
827. 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
828. 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
829. A new overlapping community detection algorithm based on similarity of neighbors in complex networks
- Creator:
- Çetin, Pelin and Amrahov, Şahin Emrah
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- overlapping community detection, complex networks, graph approach, similarity approach, and community metrics
- Language:
- English
- Description:
- Community detection algorithms help us improve the management of complex networks and provide a clean sight of them. We can encounter complex networks in various fields such as social media, bioinformatics, recommendation systems, and search engines. As the definition of the community changes based on the problem considered, there is no algorithm that works universally for all kinds of data and network structures. Communities can be disjointed such that each member is in at most one community or overlapping such that every member is in at least one community. In this study, we examine the problem of finding overlapping communities in complex networks and propose a new algorithm based on the similarity of neighbors. This algorithm runs in O(mlgm) running time in the complex network containing m number of relationships. To compare our algorithm with existing ones, we select the most successful four algorithms from the Community Detection library (CDlib) by eliminating the algorithms that require prior knowledge, are unstable, and are time-consuming. We evaluate the successes of the proposed algorithm and the selected algorithms using various known metrics such as modularity, F-score, and Normalized Mutual Information. In addition, we adapt the coverage metric defined for disjoint communities to overlapping communities and also make comparisons with this metric. We also test all of the algorithms on small graphs of real communities. The experimental results show that the proposed algorithm is successful in finding overlapping communities.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
830. 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