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522. A comparison of three trapping methods used to survey forest-dwelling Coleoptera
- Creator:
- Hyvärinen, Esko, Kouki, Jari, and Martikainen , Petri
- Type:
- article, model:article, and TEXT
- Subject:
- Abundance distribution, beetles, biodiversity inventories, boreal forest, Coleoptera, interception traps, pitfall traps, sampling, species richness, and window traps
- Language:
- English
- Description:
- Sampling of insect communities is very challenging and for reliable interpretation of results the effects of different sampling protocols and data processing on the results need to be fully understood. We compared three different commonly used methods for sampling forest beetles, freely hanging flight-intercept (window) traps (FWT), flight-intercept traps attached to trunks (TWT) and pitfall traps placed in the ground (PFT), in Scots pine dominated boreal forests in eastern Finland. Using altogether 960 traps, forming 576 sub-samples, at 24 study sites, 59760 beetles belonging to 814 species were collected over a period of a month. All of the material was identified to species, with the exception of a few species pairs, to obtain representative data for analyses. Four partly overlapping groups were used in the analyses: (1) all, (2) saproxylic, (3) rare and (4) red-listed species. In terms of the number of species collected TWTs were the most effective for all species groups and the rarer species the species group composed of (groups 1-2-3-4) the larger were the differences between the trap types. In particular, the TWTs caught most red-listed species. However, when sample sizes were standardized FWTs and TWTs caught similar number of species of all species groups. PFTs caught fewer species of all species groups, whether the sample sizes were standardized or not. In boreal forests they seem to be unsuitable for sampling saproxylic, rare and red-listed species. However, the PFTs clearly sampled different parts of species assemblages than the window traps and can be considered as a supplementary method. The abundance distribution of saproxylic species was truncated lognormal in TWT and pooled material, whereas unclassified material failed to reveal lognormal distribution in all the trap types and pooled material. The results show that even in boreal forests sample sizes of at least thousands, preferably tens of thousands of individuals, collected by a high number of traps are needed for community level studies. Relevant ecological classification of material is also very important for reliable comparisons. Differences in the performance of trap types should be considered when designing a study, and in particular when evaluating the results.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
523. A comparison of two fem-based methods for the solution of the nonlinear output regulation problem
- Creator:
- Branislav, Čelikovský, Sergej, Ruiz-León, Javier, and Orozco-Mora, Jorge
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- nonlinear output regulation, singularly perturbed equation, and gyroscope
- Language:
- English
- Description:
- The regulator equation is the fundamental equation whose solution must be found in order to solve the output regulation problem. It is a system of first-order partial differential equations (PDE) combined with an algebraic equation. The classical approach to its solution is to use the Taylor series with undetermined coefficients. In this contribution, another path is followed: the equation is solved using the finite-element method which is, nevertheless, suitable to solve PDE part only. This paper presents two methods to handle the algebraic condition: the first one is based on iterative minimization of a cost functional defined as the integral of the square of the algebraic expression to be equal to zero. The second method converts the algebraic-differential equation into a singularly perturbed system of partial differential equations only. Both methods are compared and the simulation results are presented including on-line control implementation to some practically motivated laboratory models.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
524. A comparison on the commutative neutrix convolution of distributions and the exchange formula
- Creator:
- Kilicman, Adem
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- distributions, ultradistributions, delta-function, neutrix limit, neutrix product, neutrix convolution, and exchange formula
- Language:
- English
- Description:
- Let $\tilde{f}$, $\tilde{g}$ be ultradistributions in $\mathcal Z^{\prime }$ and let $\tilde{f}_n = \tilde{f} * \delta _n$ and $\tilde{g}_n = \tilde{g} * \sigma _n$ where $\lbrace \delta _n \rbrace $ is a sequence in $\mathcal Z$ which converges to the Dirac-delta function $\delta $. Then the neutrix product $\tilde{f} \diamond \tilde{g}$ is defined on the space of ultradistributions $\mathcal Z^{\prime }$ as the neutrix limit of the sequence $\lbrace {1 \over 2}(\tilde{f}_n \tilde{g} + \tilde{f} \tilde{g}_n)\rbrace $ provided the limit $\tilde{h}$ exist in the sense that \[ \mathop {\mathrm N\text{-}lim}_{n\rightarrow \infty }{1 \over 2} \langle \tilde{f}_n \tilde{g} +\tilde{f} \tilde{g}_n, \psi \rangle = \langle \tilde{h}, \psi \rangle \] for all $\psi $ in $\mathcal Z$. We also prove that the neutrix convolution product $f \mathbin {\diamondsuit \!\!\!\!*\,}g$ exist in $\mathcal D^{\prime }$, if and only if the neutrix product $\tilde{f} \diamond \tilde{g}$ exist in $\mathcal Z^{\prime }$ and the exchange formula \[ F(f \mathbin {\diamondsuit \!\!\!\!*\,}g) = \tilde{f} \diamond \tilde{g} \] is then satisfied.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
525. A completion of $\mathbb{Z}$ is a field
- Creator:
- Marcos, José E.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- sequential convergence, convergence ring, and completion of a convergence ring
- Language:
- English
- Description:
- We define various ring sequential convergences on $\mathbb{Z}$ and $\mathbb{Q}$. We describe their properties and properties of their convergence completions. In particular, we define a convergence $\mathbb{L}_1$ on $\mathbb{Z}$ by means of a nonprincipal ultrafilter on the positive prime numbers such that the underlying set of the completion is the ultraproduct of the prime finite fields $\mathbb{Z}/(p)$. Further, we show that $(\mathbb{Z}, \mathbb{L}^\ast _1)$ is sequentially precompact but fails to be strongly sequentially precompact; this solves a problem posed by D. Dikranjan.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
526. A concise review of soft glassy rheological model of cytoskeleton
- Creator:
- Bansod, Yogesh Deepak and Burša, Jiří
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- cytoskeleton, model, sglassy rheology, and magnetic twisting cytometry
- Language:
- English
- Description:
- A cytoskeletal network contributes significantly to intracellular regulation of mechanical stresses, cell motility and cellular mechanics. Thus, it plays a vital role in defining the mechanical behaviour of the cell. Among the wide range of models proposed for dynamic behaviour of cytoskeleton, the soft glassy rheology model has gained special attention due to the resemblance of its predictions with the mechanical data measured from experiment. The soft glassy material, theory of soft glassy rheology and experiment on cytoskeleton has been discussed, which leads to a discussion of the unique features and flaws of the model. The soft glassy rheological model provides a unique explanation of the cytoskeleton ability to deform, flow and remodel. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
527. A consensus based algorithm for grounding belief formulas in internally stored perceptions
- Creator:
- Katarzyniak, Radosław and Pieczyńska - Kuchtiak, Agnieszka
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- symbol grounding, belief formulas, cognitive agent, consensus theory, and application
- Language:
- English
- Description:
- In this paper an original algorithm for tlie choice of a relevaiit belief formula is presented. Belief forinulas are treated as external representations of internal States of cognition directed at an ontologically existing atom object. This algorithrn is based on the idea of intentional semantics and uses soft methods based on the theory of consensus and choice.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
528. A construction of large graphs of diameter two and given degree from Abelian lifts of dipoles
- Creator:
- Mesežnikov, Dávid
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- the degree-diameter problem, voltage assignment and lift, and dipole
- Language:
- English
- Description:
- For any d≥11 we construct graphs of degree d, diameter 2, and order 825d2+O(d), obtained as lifts of dipoles with voltages in cyclic groups. For Cayley Abelian graphs of diameter two a slightly better result of 925d2+O(d) has been known \cite{MSS} but it applies only to special values of degrees d depending on prime powers.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
529. A constructive integral equivalent to the integral of Kurzweil
- Creator:
- Federson, Márcia
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Kurzweil integral and generalized Riemann integral
- Language:
- English
- Description:
- We slightly modify the definition of the Kurzweil integral and prove that it still gives the same integral.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
530. A constructive method to determine the variety of filiform Lie algebras
- Creator:
- Echarte, F. J., Márquez, M. C., and Núñez, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- cohomology of nilpotent Lie algebras, graded filiform Lie algebras, variety of laws of filiform Lie algebras, irreducible component, and algorithm
- Language:
- English
- Description:
- In this paper we use cohomology of Lie algebras to study the variety of laws associated with filiform Lie algebras of a given dimension. As the main result, we describe a constructive way to find a small set of polynomials which define this variety. It allows to improve previous results related with the cardinal of this set. We have also computed explicitly these polynomials in the case of dimensions 11 and 12.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public