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274802. Efficiency of two methods of sampling used to assess the abundance and species diversity of adult Syrphidae (Diptera) in mountainous meadows in the Austrian and Swiss Alps
- Creator:
- Hussain, Raja I, Walcher, Ronnie, Brandl, David, Arnberger, Arne, Zaller, Johann G, and Frank, Thomas
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- dvoukřídlí, pestřenkovití, Diptera, Syrphidae, hoverflies, sampling methods, observation-plot, line-transect, alpine grassland, 2, and 59
- Language:
- English
- Description:
- The outcome of assessments of the biodiversity of a taxonomic group often depend on the sampling method. The choice of an adequate method is especially important for biomonitoring purposes. In this study, the effectiveness of two methods of sampling syrphids (Diptera: Syrphidae) is compared: observation plot method vs. line transect, both sampled by sweep netting. Altogether, 18 meadows were selected in three mountain regions in the Austrian and Swiss Alps. We recorded a significantly higher abundance and richness of syrphids using the observation plot method than the line transect method in 2015. Comparing data for one region recorded in 2015 and 2016, similar results were obtained. Syrphid species assemblages were affected by sampling method in both years. More syrphid species and individuals were recorded using the observation plot method, which makes it more suitable for studies aiming at comparing differences in the numbers of adult syrphids in different grassland habitats., Raja I. Hussain, Ronnie Walcher, David Brandl, Arne Arnberger, Johann G. Zaller, Thomas Frank., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274803. Efficiency of various methods of the search for periodic orbits
- Creator:
- Hadrava, P. and Kadrnoška, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- solar system, periodic orbits, and dynamics of asteroids
- Language:
- Czech
- Description:
- The periodic orbits in circular restricted 3-body problem are calculated by different numerical as well as analytical methods. The efficiency of both kinds are compared in this contribution. The improvement of analytical methods can be achieved by an artificial splitting of perturbation term. The analytical approximations are thus sufficiently accurate even for large values of mass ratio μ. The use of these approximations as a zero-order approximation In numerical codes for search for periodic orbits improves their efficiency also.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274804. Efficient algorithm to solve optimal boundary control problem for burgers´ equation
- Creator:
- Malek, Alaedoin, Nataj, Rochayer Ebrahim, and Yazdanpanah, Mohamad Javad
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- optimal boundary control, Burgers´ equation, conjugate gradient method, modal expansion technique, and control parametrization
- Language:
- English
- Description:
- In this paper, we propose a novel algorithm for solving an optimal boundary control problem of the Burgers' equation. The solving method is based on the transformation of the original problem into a homogeneous boundary conditions problem. This transforms the original problem into an optimal distributed control problem. The modal expansion technique is applied to the distributed control problem of the Burgers' equation to generate a low-dimensional dynamical system. The control parametrization method is formulated for approximating the time-varying control by a finite term of the orthogonal functions with unknown coefficients determined through an optimization process. The minimization of the objective functional is performed by using a conjugate gradient method. The accuracy and convergent rate of this hybrid method are shown by some numerical examples.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274805. Efficient application of e-invariants in finite element method for an elastodynamic equation
- Creator:
- Balazovjech, Martin and Halada, Ladislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- e-invariants, finite element method, elastodynamics equation, and efficient computation
- Language:
- English
- Description:
- We introduce a new efficient way of computation of partial differential equations using a hybrid method composed from FEM in space and FDM in time domain. The overall computational scheme is explicit in time. The key idea of the suggested way is based on a transformation of standard basis functions into new basis functions. The results of this matrix transformation are e-invariants (effective invariants) with such suitable properties which save the number of arithmetical operations needed for a problem solution. The application of this procedure and its effectiveness for 2D problem was the first time published in \cite{halabala}. Now we describe the generalization of this procedure for 3D problem. In order to present the main principle of our process and its advantage, we first explain the main idea of our approach on a simple 1D example and then the application of the e-invariants on an elastodynamics equation using hexahedral elements in 3D is described. Finally, the efficiency of the suggested method in both cases from the point of the required number of arithmetical operations is analyzed. The result of this analysis confirms computational efficiency the suggested method and the usefulness of e-invariants which save only the essential information needed for the computation. Moreover, the method can be used for various types of elements and equations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274806. Efficient collective redress mechanisms in Visegrad 4 Countries: an achievable target?
- Creator:
- Simon, Rita and Müllerová, Hana
- Publisher:
- Ústav státu a práva AV ČR, v.v.i
- Format:
- electronic, electronic resource, remote, bez média, online zdroj, and 1 online zdroj (280 stran).
- Type:
- model:monograph and TEXT
- Subject:
- Soukromé právo, náhrada škody, reparations, země Visegrádské skupiny, Visegrád Group countries, kolektivní odškodnění, collective redress, 347.426.6, 347.513, (4-191.2), (082), (0.034.2:08), 16, and 347
- Language:
- English
- Description:
- Rita Simon, Hana Müllerová (eds.)., Obsahuje bibliografii a bibliografické odkazy, and born digital
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
274807. Efficient measurement of higher-order statistics of stochastic processes
- Creator:
- Magiera, Wladyslaw, Libal, Urszula, and Wielgus, Agnieszka
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- covariance matrix, higher-order statistics, adaptive, and nonlinear
- Language:
- English
- Description:
- This paper is devoted to analysis of block multi-indexed higher-order covariance matrices, which can be used for the least-squares estimation problem. The formulation of linear and nonlinear least squares estimation problems is proposed, showing that their statements and solutions lead to generalized `normal equations', employing covariance matrices of the underlying processes. Then, we provide a class of efficient algorithms to estimate higher-order statistics (generalized multi-indexed covariance matrices), which are necessary taking in mind practical aspects of the nonlinear treatment of the least-squares estimation problem. The algorithms are examined for different higher-order and non-Gaussian processes (time-series) and an impact of signal properties on covariance matrices is analysed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274808. Efficient methods of automatic calibration for rainfall-runoff modelling in the Floreon+ system
- Creator:
- Theuer, M., Vavřík, R., Vondrák, V., Kuchař, Š., Šír, B., and Portero, A.
- Format:
- jiný
- Type:
- model:article and TEXT
- Subject:
- rainfall-runoff modelling, automatic calibration, optimization algorithms, genetic algorithms, and parrallel implementation
- Language:
- English
- Description:
- Calibration of rainfall-runoff model parameters is an inseparable part of hydrological simulations. To achieve more accurate results of these simulations, it is necessary to implement an efficient calibration method that provides sufficient refinement of the model parameters in a reasonable time frame. In order to perform the calibration repeatedly for large amount of data and provide results of calibrated model simulations for the flood warning process in a short time, the method also has to be automated. In this paper, several local and global optimization methods are tested for their efficiency. The main goal is to identify the most accurate method for the calibration process that provides accurate results in an operational time frame (typically less than 1 hour) to be used in the flood prediction Floreon\textsuperscript{+} system. All calibrations were performed on the measured data during the rainfall events in 2010 in the Moravian-Silesian region (Czech Republic) using our in-house rainfall-runoff model.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274809. Efficient query processing over mirror servers using genetic algorithms
- Creator:
- Sleit, A., Al-Mbaideen , W., Alzabin , N., Dawood, H., and Alqarute, K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Evolutionary algorithms, genetic elgorithms, mirror serves, server selection, and load balancer
- Language:
- English
- Description:
- In a mirror server environment, clients request services from servers. Therefore, the system must have an intelligent algorithm to select the most suitable server to fulfill a coming request. Choosing such a server for a particular client may be very difficult. Evolutionary techniques can be utilized to determine the server best suited to a particular client request based on parameters such as processing and reply times. Usage of genetic algorithms in server selection is researched in this paper taking into consideration various probabilities for mutation and crossover.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
274810. Efficient training of backpropagation neural networks
- Creator:
- Otair , Mohammed A. and Salameh, Walid A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Neural networks, backpropagation, momentum, Delta-Bar-Delta, and optical backpropqagation
- Language:
- English
- Description:
- This paper focuses on gradient-based backpropagation algorithms that use either a common adaptive learning rate for all weights or a separate adaptive learning rate for each weight. The learning-rate adaptation is based on descent techniques and estimates of the local constants that are obtained without additional error function and gradient evaluations. This paper proposes three algorithms to improve the different versions of backpropagation training in terms of both convergence rate and convergence characteristics, such as stable learning and robustness to oscillations. The new modification consists of a simple change in the error signal function. Experiments are conducted to compare and evaluate the convergence behavior of these gradient-based training algorithms with three training problems: XOR, encoding problem and character recognition, which are popular training problems.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public