Comparison of Hybrid PSO-SA Algorithm and Genetic Algorithm for Classification

In this work, we propose and present a Hybrid particle swarm optimization-Simulated annealing algorithm and compare it with a Genetic algorithm for training respectively neural networks of identical architectures. These neural networks were then tested on a classification task. In particle swarm optimization, behavior of a particle is influenced by the experiential knowledge of the particle as well as socially exchanged information. Particle swarm optimization follows a parallel search strategy. In simulated annealing uphill moves are made in the search space in a stochastic fashion in addition to the downhill moves. Simulated annealing therefore has better scope of escaping local minima and reach a global minimum in the search space. Thus simulated annealing gives a selective randomness to the search. Genetic algorithm performs parallel and randomized search. The goal of training the neural network is to minimize the sum of the squares of the error between the target and observed output values for all the training samples and to deliver good test performance on the test inputs. We compared the performance of the neural networks of identical architectures trained by the  Hybrid particle swarm optimization-simulated annealing and Genetic algorithm respectively on a classification task and noted the results obtained. Neural network trained by Hybrid particle swarm optimization-simulated annealing has given better results compared to the neural network trained by the Genetic algorithm in the tests conducted by us. Keywords: Classification, Hybrid particle swarm optimization-Simulated annealing, Simulated Annealing, Genetic algorithm, Neural Network etc

The Impact of Valency and the Orientation of the Members on the Global Stability of Lattice Steel Dome

Different single-layer lattice domes are created based on varying the arrangement of members. Although the stability of triangulated lattice domes has been studied earlier, the influence of the arrangement of members on their stability has not been investigated. The arrangement of members in lattice structures can be redefined based on the valency of different elements and the orientation of the members. Valency gives the interconnection between different elements, and orientation provides the spatial arrangement of the member with respect to the circumferential and radial directions. The variation of these two factors fundamentally defines the overall stability of single-layer lattice domes. Therefore, the influence of the valency and orientation of members on the stability of single-layer lattice domes is studied in this paper by comparing the elasto-plastic stability of commonly adopted single-layer lattice dome configurations, such as Kiewitt, Schwedler, Lamella, Radial rib, Sunflower, and Hexagon domes. The geometrical and material non-linear analyses of the selected single-layer domes reveal that the higher edge valency of vertices, higher vertex valency of cells, and the members oriented along the radial and circumferential directions increase the overall stability of the structure. These results help to identify the optimum number and orientation of the members at each node of the structure so that designers can adopt new configurations with higher stability and load capacity

Strain-Dependent Photoluminescence Behavior of CdSe/CdS Nanocrystals with Spherical, Linear, and Branched Topologies

The photoluminescence of CdSe/CdS core/shell quantum dots, nanorods, and tetrapods is investigated as a function of applied hydrostatic and non-hydrostatic pressure. The optoelectronic properties of all three nanocrystal morphologies are affected by strain. Furthermore, it is demonstrated that the unique morphology of a tetrapod is highly sensitive to non-isotropic stress environments. Seeded tetrapods can thereby serve as an optical strain gauge, capable of measuring forces on the order of nanonewtons. We anticipate that a nanocrystal strain gauge with optical readout will be useful for applications ranging from sensitive optomechanical devices to investigations of biomechanical processes

A convenient category of locally preordered spaces

As a practical foundation for a homotopy theory of abstract spacetime, we extend a category of certain compact partially ordered spaces to a convenient category of locally preordered spaces. In particular, we show that our new category is Cartesian closed and that the forgetful functor to the category of compactly generated spaces creates all limits and colimits.Comment: 26 pages, 0 figures, partially presented at GETCO 2005; changes: claim of Prop. 5.11 weakened to finite case and proof changed due to problems with proof of Lemma 3.26, now removed; Eg. 2.7, statement before Lem. 2.11, typos, and other minor problems corrected throughout; extensive rewording; proof of Lem. 3.31, now 3.30, adde

Системный анализ процесса затвердевания литых заготовок разной массы и назначения

Выявлены особенности пространственно-временной эволюции температурных полей в процессе затвердевания разных заготовок (слитков и отливок) для повышения их качества.Виявлено особливості просторово-часової еволюції температурних полів в процесі тверднення різних заготовок (зливків та виливків) для підвищення їх якості.It is revealed the peculiarities of distance-time evolution of the temperature fields in solidification process different billets (ingots and casts) for raise them quality

Interaction between polymorphisms of the Human Leukocyte Antigen and HPV-16 Variants on the risk of invasive cervical cancer

<p>Abstract</p> <p>Background</p> <p>Persistent infection with oncogenic types of human papillomavirus (HPV) is the major risk factor for invasive cervical cancer (ICC), and non-European variants of HPV-16 are associated with an increased risk of persistence and ICC. HLA class II polymorphisms are also associated with genetic susceptibility to ICC. Our aim is to verify if these associations are influenced by HPV-16 variability.</p> <p>Methods</p> <p>We characterized HPV-16 variants by PCR in 107 ICC cases, which were typed for <it>HLA-DQA1</it>, <it>DRB1 </it>and <it>DQB1 </it>genes and compared to 257 controls. We measured the magnitude of associations by logistic regression analysis.</p> <p>Results</p> <p>European (E), Asian-American (AA) and African (Af) variants were identified. Here we show that inverse association between <it>DQB1*05 </it>(adjusted odds ratio [OR] = 0.66; 95% confidence interval [CI]: 0.39–1.12]) and HPV-16 positive ICC in our previous report was mostly attributable to AA variant carriers (OR = 0.27; 95%CI: 0.10–0.75). We observed similar proportions of <it>HLA DRB1*1302 </it>carriers in E-P positive cases and controls, but interestingly, this allele was not found in AA cases (p = 0.03, Fisher exact test). A positive association with <it>DRB1*15 </it>was observed in both groups of women harboring either E (OR = 2.99; 95% CI: 1.13–7.86) or AA variants (OR = 2.34; 95% CI: 1.00–5.46). There was an inverse association between <it>DRB1*04 </it>and ICC among women with HPV-16 carrying the 350T [83L] single nucleotide polymorphism in the <it>E6 </it>gene (OR = 0.27; 95% CI: 0.08–0.96). An inverse association between <it>DQB1*05 </it>and cases carrying 350G (83V) variants was also found (OR = 0.37; 95% CI: 0.15–0.89).</p> <p>Conclusion</p> <p>Our results suggest that the association between HLA polymorphism and risk of ICC might be influenced by the distribution of HPV-16 variants.</p

Instabilities in the wake of an inclined prolate spheroid

We investigate the instabilities, bifurcations and transition in the wake behind a 45-degree inclined 6:1 prolate spheroid, through a series of direct numerical simulations (DNS) over a wide range of Reynolds numbers (Re) from 10 to 3000. We provide a detailed picture of how the originally symmetric and steady laminar wake at low Re gradually looses its symmetry and turns unsteady as Re is gradually increased. Several fascinating flow features have first been revealed and subsequently analysed, e.g. an asymmetric time-averaged flow field, a surprisingly strong side force etc. As the wake partially becomes turbulent, we investigate a dominating coherent wake structure, namely a helical vortex tube, inside of which a helical symmetry alteration scenario was recovered in the intermediate wake, together with self-similarity in the far wake.Comment: Book chapter in "Computational Modeling of Bifurcations and Instabilities in Fluid Dynamics (A. Gelfgat ed.)", Springe