Number of results to display per page
Search Results
802. A new error estimate for a fully finite element discretization scheme for parabolic equations using Crank-Nicolson method
- Creator:
- Bradji, Abdallah and Fuhrmann, Jürgen
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- parabolic equation, finite element method, Crank-Nicolson method, and new error estimate
- Language:
- English
- Description:
- Finite element methods with piecewise polynomial spaces in space for solving the nonstationary heat equation, as a model for parabolic equations are considered. The discretization in time is performed using the Crank-Nicolson method. A new a priori estimate is proved. Thanks to this new a priori estimate, a new error estimate in the discrete norm of W1,∞(L 2 ) is proved. An L∞(H1 )-error estimate is also shown. These error estimates are useful since they allow us to get second order time accurate approximations for not only the exact solution of the heat equation but also for its first derivatives (both spatial and temporal). Even the proof presented in this note is in some sense standard but the stated W1,∞(L 2 )- error estimate seems not to be present in the existing literature of the Crank-Nicolson finite element schemes for parabolic equations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
803. A new family of compound lifetime distribution
- Creator:
- Asgharzadeh, A., Bakouch, Hassan S., Saralees, and Esmaeili, L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- estimation, failure rate shapes, moments, and Poisson-Lindley distribution
- Language:
- English
- Description:
- In this paper, we introduce a general family of continuous lifetime distributions by compounding any continuous distribution and the Poisson-Lindley distribution. It is more flexible than several recently introduced lifetime distributions. The failure rate functions of our family can be increasing, decreasing, bathtub shaped and unimodal shaped. Several properties of this family are investigated including shape characteristics of the probability density, moments, order statistics, (reversed) residual lifetime moments, conditional moments and Rényi entropy. The parameters are estimated by the maximum likelihood method and the Fisher's information matrix is determined. Several special cases of this family are studied in some detail. An application to a real data set illustrates the performance of the family of distributions.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
804. A new family of spectrally arbitrary ray patterns
- Creator:
- Mei, Yinzhen, Gao, Yubin, Shao, Yanling, and Wang, Peng
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, polynomy, mathematics, polynomials, ray pattern, potentially nilpotent, spectrally arbitrary ray pattern, 13, and 51
- Language:
- English
- Description:
- An n × n ray pattern A is called a spectrally arbitrary ray pattern if the complex matrices in Q(A) give rise to all possible complex polynomials of degree n. In a paper of Mei, Gao, Shao, and Wang (2014) was proved that the minimum number of nonzeros in an n×n irreducible spectrally arbitrary ray pattern is 3n-1. In this paper, we introduce a new family of spectrally arbitrary ray patterns of order n with exactly 3n - 1 nonzeros., Yinzhen Mei, Yubin Gao, Yanling Shao, Peng Wang., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
805. A new family of trivariate proper quasi-copulas
- Creator:
- Úbeda-Flores, Manuel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- copula, mass distribution, and quasi-copula
- Language:
- English
- Description:
- In this paper, we provide a new family of trivariate proper quasi-copulas. As an application, we show that W3 - the best-possible lower bound for the set of trivariate quasi-copulas (and copulas) - is the limit member of this family, showing how the mass of W3 is distributed on the plane x+y+z=2 of [0,1]3 in an easy manner, and providing the generalization of this result to n dimensions.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
806. A new fish haemogregarine from South Africa and its suspected dual transmission with trypanosomes by a marine leech
- Creator:
- Hayes, Polly M., Smit, Nico J., Seddon, Alan M., Wertheim, David F., and Davies, Angela J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Haemogregarina curvata, trypanosomes, leeches, development, intertidal fishes, and South Africa
- Language:
- English
- Description:
- Twenty two percent (22/98) of intertidal fishes of 10 species captured in South Africa at Koppie Alleen, De Hoop Nature Reserve (south coast) and Mouille Point, Cape Town (west coast), harboured single or combined infections of haemogregarines, trypanosomes and an intraerythrocytic parasite resembling a Haemohormidium sp. The haemogregarines included the known species Haemogregarina (sensu lato) bigemina (Laveran et Mesnil, 1901) Siddall, 1995 and Haemogregarina (sensu lato) koppiensis Smit et Davies, 2001, while Haemogregarina (sensu lato) curvata sp. n. was observed in Clinus cottoides Valenciennes and Parablennius cornutus (L.) at Koppie Alleen. This last haemogregarine is characterised particularly by its distinctly curved gamonts. Also at Koppie Alleen, squash and histological preparations of 9/10 leeches, Zeylanicobdella arugamensis De Silva, 1963, taken from infected C. cottoides and P. cornutus contained developmental stages of H. curvata and/or trypanosomes, but these were absent from haematophagous gnathiid isopods (Gnathia africana Barnard, 1914) taken from infected fishes. It is suspected that Z. arugamensis transmits the haemogregarine and trypanosomes simultaneously between fishes, a double event unreported previously from the marine environment.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
807. A new form of fuzzy α-compactness
- Creator:
- Shi, Fu Gui
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- L-topology, compactness, α-compactness, countable α-compactness, αLindelöf property, α-irresolute map, and α-continuous map
- Language:
- English
- Description:
- A new form of α-compactness is introduced in L-topological spaces by α-open L-sets and their inequality where L is a complete de Morgan algebra. It doesn’t rely on the structure of the basis lattice L. It can also be characterized by means of α-closed L-sets and their inequality. When L is a completely distributive de Morgan algebra, its many characterizations are presented and the relations between it and the other types of compactness are discussed. Countable α-compactness and the α-Lindelöf property are also researched.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
808. A new form of raabeia-type actinosporean (Myxozoa) from the oligochaete Uncinais uncinata
- Creator:
- Koprivnikar, Janet and Desser, Sherwin S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Myxozoa, Actinosporea, raabeia, Oligochaeta, and Uncinais uncinata
- Language:
- English
- Description:
- In a study of the oligochaete fauna and their actinosporean parasites in three lakes in Algonquin Park, Canada, a novel form of raabeia-type actinosporean was observed in a single specimen of Uncinais uncinata (∅ersted) (Naididae). This form differs from those previously described in its small size, and by having caudal processes that gradually widen and terminate with a single prominent branch.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
809. A new generation of multichannel seismic apparatus and its practical application in standalone and array monitoring
- Creator:
- Brož, milan and Štrunc, Jaroslav
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, seizmicita, seismicity, building, analog-to-digital converter, seismic array, weak event, monitoring network, 7, and 551
- Language:
- English
- Description:
- A quantitatively new analog-to-digital converter (ADC) module has been developed during 2010, in co-operation with Tedia Ltd. The module has a 28-bit final resolution and uses 32-bit arithmetic. There are two versions, with four and twelve analog inputs. The 4-input module replaces the original 21-bit version, produced until 2009. The 12-input module is intended to be deployed in small-aperture seismic arrays. The whole set consists of four 3-channel detached modules that can be interconnected with the main module using a cable of up to 100 m in length. This design increases signal-to-noise ratio (SNR) by placing the A/D part as close to the seismograph as possible in order to transmit digital data for storage. All channels are sampled coherently so that all four sensors are automatically synchronised. It allows the detection of local events even though the sync-signal is absent. In other words, the 12-input module is suitable for ad-hoc field measurements even in places where there is no GPS signal. All arrays operated by the Institute of Rock Structure and Mechanics (IRSM) are going to be upgraded to use these modules and some new sites will also be set-up with this innovative equipment (e.g. Lazy in Western Bohemia and Dobrá Voda in Slovakia)., Milan Brož and Jaroslav Štrunc., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
810. A new genus and species of Heligmonellidae (Nematoda: Trichostrongylina) parasitic in Delomys dorsalis (Rodentia: Sigmodontinae) from Misiones, Argentina
- Creator:
- Digiani, María Celina and Kinsella, John M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- taxonomy, Nippostrongylinae, synlophe, right lobe hypertrophy, right lobe rotation, caudal appendage, and South America
- Language:
- English
- Description:
- Alippistrongylus bicaudatus gen. et sp. n. (Nematoda: Heligmonellidae) is described from the striped Atlantic forest rat, Delomys dorsalis (Hensel) (Rodentia: Sigmodontinae), from the province of Misiones in Argentina. The new genus and species is characterised by a synlophe of 21 unequal ridges in both sexes without a gradient in size, with two ridges weakly sclerotised and oriented perpendicularly in the dorsal left quadrant; males with a highly dissymmetrical bursa with a hypertrophied right lobe, and females with a dorsal conical appendage just posterior to the vulva, conferring a two-tailed appearance to the female worms.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public