Recently it has been shown that sum and product are not the only operations that can be used in order to define concrete approximation operators but several operations provided by fuzzy logic can be used. In this sens...
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Recently it has been shown that sum and product are not the only operations that can be used in order to define concrete approximation operators but several operations provided by fuzzy logic can be used. In this sense, in the present paper, pseudo-linear approximation operators of Shepard-type are studied from the practical point of view, in function approximation. It is shown that in several cases these outperform classical approximation operators based on sum and product operations.
A new method is introduced for identifying the electrical conductivity of concrete and the impedance of steel-concrete interface by using some potential data which are measured on the concrete surface
A new method is introduced for identifying the electrical conductivity of concrete and the impedance of steel-concrete interface by using some potential data which are measured on the concrete surface
High-throughput generation of new types of relational biological datasets is creating a demand for network-based signal processing and pattern recognition to provide new insights. Such networks are often too large to ...
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High-throughput generation of new types of relational biological datasets is creating a demand for network-based signal processing and pattern recognition to provide new insights. Such networks are often too large to interpret visually and too complicated to be explained solely based on local topological properties. Just as signal processing and statistical techniques have been used in traditional, sequential-based biological datasets, so too are methodologies needed to automatically discern patterns in the huge, emerging networks. One way to do this is by transforming these very large networks into discernable epitomes, or abstracts, of the original networks. This work presents an approach for doing this via topological compression. Through capturing nodes' global topologies and subsequent compression, a new network epitome can be derived. Here, this is done with an E. Coli gene regulation network, resulting in biological findings that could not be derived from the local topology of the original network.
In this paper, we investigate the properties of lethal genes in E. coli, our model organism. Topological analysis of networks of functional interactions among genes has shown that lethal genes share common local conne...
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In this paper, we investigate the properties of lethal genes in E. coli, our model organism. Topological analysis of networks of functional interactions among genes has shown that lethal genes share common local connectivity properties. In this paper, we analyze cellular networks across three domains. We show that a stochastic global topological analysis, via random walks, is more effective at predicting gene lethality than simply looking at local topology using the standard hub-based method. We also introduce the possibility of using metabolic pathways to understand lethal genes, as regulating these pathways is among one of the most important functions of the gene-encoded proteins. Additionally, we analyze lethal genes in terms of the Gene Ontology (GO) and find that the graph forms two highly connected clusters that are each GO enriched for specific terms. We also find that lethal metabolic regulators are extremely enriched. Finally, we provide applications of the work and avenues for future research.
Crystal-melt interfacial free energies (γ) are computed for hcp Mg by employing equilibrium molecular-dynamics (MD) simulations and the capillary-fluctuation method (CFM). This work makes use of a newly developed emb...
Crystal-melt interfacial free energies (γ) are computed for hcp Mg by employing equilibrium molecular-dynamics (MD) simulations and the capillary-fluctuation method (CFM). This work makes use of a newly developed embedded-atom-method (EAM) interatomic potential for Mg fit to crystal, liquid, and melting properties. We describe how the CFM, which has previously been applied to cubic systems only, can be generalized for studies of hcp metals by employing a parametrization for the orientation dependence of γ in terms of hexagonal harmonics. The method is applied in the calculation of the Turnbull coefficient (α) and crystalline anisotropies of γ. We obtain a value of α=0.48, with interfacial free energies for different high-symmetry orientations differing by approximately 1%. These results are compared to those obtained in previous MD-CFM studies for cubic EAM metals as well as experimental studies of solid-liquid interfaces in hcp alloys. In addition, the implications of our results for the prediction of dendrite growth directions in hcp metals are discussed.
Real collective density variables C(k) [cf. Eq. (1.3)] in many-particle systems arise from nonlinear transformations of particle positions, and determine the structure factor S(k), where k denotes the wave vector. Our...
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Real collective density variables C(k) [cf. Eq. (1.3)] in many-particle systems arise from nonlinear transformations of particle positions, and determine the structure factor S(k), where k denotes the wave vector. Our objective is to prescribe C(k) and then to find many-particle configurations that correspond to such a target C(k) using a numerical optimization technique. Numerical results reported here extend earlier one- and two-dimensional studies to include three dimensions. In addition, they demonstrate the capacity to control S(k) in the neighborhood of ∣k∣=0. The optimization method employed generates multiparticle configurations for which S(k)∝∣k∣α, ∣k∣⩽K, and α=1, 2, 4, 6, 8, and 10. The case α=1 is relevant for the Harrison-Zeldovich model of the early universe, for superfluid He4, and for jammed amorphous sphere packings. The analysis also provides specific examples of interaction potentials whose classical ground states are configurationally degenerate and disordered.
The method of fundamental solutions (MFS) is first proposed in 1964 by Kupradze and theoretical basis of this method is constructed at the end of 1980's. As a meshless method, no domain meshing is required for MFS...
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Incomplete LU factorization is a valuable preconditioning approach for sparse iterative solvers. An "ideal" but inefficient preconditioner for the iterative solution of Ax = b is A-1 itself. This paper descr...
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Incomplete LU factorization is a valuable preconditioning approach for sparse iterative solvers. An "ideal" but inefficient preconditioner for the iterative solution of Ax = b is A-1 itself. This paper describes a preconditioner based on sparse approximations to partitioned representations of A-1, in addition to the results of implementation of the proposed method in a shared memory parallel environment. The partitioned inverses are normally somewhat sparse. Their sparsity can be enhanced with suitable ordering and partitioning algorithms. Sparse approximations to these partitioned inverse representations can be obtained either by discarding selected nonzero entries of these inverses or by precluding the creation of some inversion fills. Experimental results indicate that the use of these partitioned incomplete inverses as preconditioners results in excellent highly parallel preconditioners.
Through investigation of transient phase characteristics, a methodology is developed to optimize the phase resetting properties of robust nonlinear biological oscillators;in particular, those of the circadian rhythm. ...
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Most edge detection algorithms include three main stages: smoothing, differentiation, and labeling. In this paper, we evaluate the performance of algorithms in which competitive learning is applied first to enhance ed...
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ISBN:
(纸本)1604238216
Most edge detection algorithms include three main stages: smoothing, differentiation, and labeling. In this paper, we evaluate the performance of algorithms in which competitive learning is applied first to enhance edges, followed by an edge detector to locate the edges. In this way, more detailed and relatively more unbroken edges can be found as compared to the results when an edge detector is applied alone. The algorithms compared are K-Means, SOM and SOGR for clustering, and Canny and GED for edge detection. Perceptionally, best results were obtained with the GED-SOGR algorithm. The SOGR is also considerably simpler and faster than the SOM algorithm.
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