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632. 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
633. 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
634. 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
635. 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
636. A new feather mite of the genus Dolichodectes (Astigmata: Proctophyllodidae) from Hippolais polyglotta (Passeriformes: Acrocephalidae) in Spain
- Creator:
- Mironov, Sergey V, Doña, Jorge, and Jovani, Roger
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, Acari, Pterodectinae, ectoparasites, systematics, passerines, molecular study, COI, 2, and 59
- Language:
- English
- Description:
- A new feather mite species, Dolichodectes hispanicus sp. n. (Astigmata: Proctophyllodidae), is described from the Melodious Warbler Hippolais polyglotta (Vieillot) (Passeriformes: Acrocephalidae) in Spain. The new species is closest to the type species of the genus, D. edwardsi (Trouessart, 1885) from the Grear Reed-Warbler Acrocephalus arundinaceus (Linnaeus) (Acrocephalidae). Adults of D. hispanicus differ from those of D. edwardsi by dimensional characteristics, in particular, by having shorter aedeagus that does not extend to the anal suckers in males and shorter hysteronotal shield in females. Tritonymphs of D. hispanicus are much more distinctive and differ from those of D. edwardsi by having the prodorsal shield covering all the prodorsum, the hysteronotal shield occupying about three quarters of the hysterosoma, and idiosomal setae h3 being filiform. The morphological description of the new species is augmented by sequence data from the mitochondrial cytochrome c oxidase subunit I gene fragment (COI)., Sergey V. Mironov, Jorge Doña, Roger Jovani., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
637. 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
638. A new genus and four new species of dactylogyrids (Monogenea), gill parasites of pimelodid catfishes (Siluriformes: Pimelodidae) in South America and the reassignment of Urocleidoides megorchis Mizelle et Kritsky, 1969
- Creator:
- Acosta, Aline A, Mendoza-Palmero, Carlos A, Silva, Reinaldo J. da, and Tomáš Scholz
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- morfologie (biologie), Monogenea, morphology (biology), Jižní Amerika, South America, Ancyrocephalinae, integrative taxonomy, 28S rRNA, Sorubiminae, Neotropical region, 2, and 59
- Language:
- English
- Description:
- Nanayella gen. n. is proposed to accommodate four new species of dactylogyrid monogeneans found on the gills of two species of pimelodid catfishes (Siluriformes) from the Amazon River basin in Peru and the Upper Paraná River basin in Brazil. Nanayella gen. n. is mainly characterised by the presence of modified hook pairs 5 and 6, which have a slender shank with slightly enlarged base, inconspicuous thumb, and straight point. Nanayella aculeatrium gen. n. et sp. n. (type species) from Sorubim lima (Bloch et Schneider) (type host) differs from its congeners mainly by possessing seven sclerotised spines on one side of circular ornamentation of the vaginal atrium. Nanayella fluctuatrium gen. n. et sp. n. is characterised by the presence of sclerotised undulations surrounding the circular ornamentation of the vaginal atrium. Nanayella amplofalcis gen. n. et sp. n. is typified by possessing hook pairs 1 and 2 with a robust, wide shank and a round, weakly sclerotised subunit at the base. Nanayella processusclavis gen. n. et sp. n. differs from congeners by the presence of a conspicuous posterior medial process on the dorsal bar. Urocleidoides megorchis Mizelle et Kritsky, 1969 described from the gills of S. lima in Brazil is transferred to Nanayella gen. n. as Nanayella megorchis comb. n. based on morphological and molecular evidence. Analyses of partial sequences of the 28S rRNA gene revealed all five species of the new genus to form a monophyletic clade within a bigger clade comprised of dactylogyrids of South American pimelodids., Aline A. Acosta, Carlos A. Mendoza-Palmero, Reinaldo J. da Silva, Tomáš Scholz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
639. A new genus and new species of Phoridae (Diptera) from Poland
- Creator:
- Disney, R. Henry L. and Durska, Ewa
- Type:
- article, model:article, and TEXT
- Subject:
- Phoridae, Poloniphora, new genus, Megaselia, Phora, new species, and Poland
- Language:
- English
- Description:
- One new genus and seven new species of Phoridae (Diptera) are described from Bialowieska Forest in Poland, namely Poloniphora Disney & Durska gen, n. with the species P. bialoviensis Disney sp. n., Megaselia henrydisneyi Durska sp. n., M. joannae Disney sp. n., M. marekdurskii Disney sp. n., M. teresamajewskae Disney sp. n.: M. trojani Disney sp. n., Phora michali Disney sp. n., The new genus shows affinity with Australasian genera, Beckerina Malloch and Eocene fossils erroneously assigned to Megaselia in the past.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
640. A new genus and new species of Staphylinidae (Coleoptera) from Baltic amber
- Creator:
- Paśnik, Grzegorz and Kubisz, Daniel
- Type:
- article, model:article, and TEXT
- Subject:
- Coleoptera, Staphylinidae, Lathrobium, Sepedophilus, Palaeosepedophilus, Dictyon, Phymatura, Aleochara, new genus, new species, and Baltic amber
- Language:
- English
- Description:
- One new genus and nine new species of Staphylinidae are described from Baltic amber, namely Palaeosepedophilus gen.n. and the species P. succinicus sp.n., Lathrobium balticum sp.n., Lathrobium succini sp.n., Lathrobium ambricum sp.n., Lathrobium jantaricum sp.n., Sepedophilus balticus sp.n., Dictyon antiquus sp.n., Phymatura electrica sp.n., Aleochara baltica sp.n. Their affinity with related species is discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public