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42. Boundedness in a quasilinear parabolic-parabolic chemotaxis system with nonlinear logistic source

Creator:
Liu, Ji and Zheng, Jia-Shan
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, boundedness, chemotaxis, nonlinear logistic source, 13, and 51
Language:
English
Description:
We study a quasilinear parabolic-parabolic chemotaxis system with nonlinear logistic source, under homogeneous Neumann boundary conditions in a smooth bounded domain. By establishing proper a priori estimates we prove that, with both the diffusion function and the chemotaxis sensitivity function being positive, the corresponding initial boundary value problem admits a unique global classical solution which is uniformly bounded. The result of this paper is a generalization of that of Cao (2014)., Ji Liu, Jia-Shan Zheng., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

43. Boundedness of para-product operators on spaces of homogeneous type

Creator:
Xiao, Yayuan
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, ohraničení, boundedness, Calderón-Zygmund singular integral operator, para-product, 13, and 51
Language:
English
Description:
We obtain the boundedness of Calderón-Zygmund singular integral operators T of non-convolution type on Hardy spaces Hp(X) for 1/(1 + ε) < p < 1, where X is a space of homogeneous type in the sense of Coifman and Weiss (1971), and ε is the regularity exponent of the kernel of the singular integral operator T. Our approach relies on the discrete Littlewood-Paley-Stein theory and discrete Calderón’s identity. The crucial feature of our proof is to avoid atomic decomposition and molecular theory in contrast to what was used in the literature., Yayuan Xiao., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

44. Bounds for the number of meeting edges in graph partitioning

Creator:
Zeng, Qinghou and Hou, Jianfeng
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, graph, weighted hypergraph, partition, judicious partition, 13, and 51
Language:
English
Description:
Let $G$ be a weighted hypergraph with edges of size at most 2. Bollobás and Scott conjectured that $G$ admits a bipartition such that each vertex class meets edges of total weight at least $(w_1-\Delta_1)/2+2w_2/3$, where $w_i$ is the total weight of edges of size $i$ and $\Delta_1$ is the maximum weight of an edge of size 1. In this paper, for positive integer weighted hypergraph $G$ (i.e., multi-hypergraph), we show that there exists a bipartition of $G$ such that each vertex class meets edges of total weight at least $(w_0-1)/6+(w_1-\Delta_1)/3+2w_2/3$, where $w_0$ is the number of edges of size 1. This generalizes a result of Haslegrave. Based on this result, we show that every graph with $m$ edges, except for $K_2$ and $K_{1,3}$, admits a tripartition such that each vertex class meets at least $\lceil{2m}/5\rceil$ edges, which establishes a special case of a more general conjecture of Bollobás and Scott., Qinghou Zeng, Jianfeng Hou., and Obsahuje bibliografické odkazy
Rights:
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45. Brněnský seminář o Bohuslavu Hostinském

Creator:
Černohorský, Martin
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
Hostinský, Bohuslav, 1884-1951, semináře, fyzika, matematika, seminars, physics, mathematics, 6, and 53
Language:
Czech
Description:
Na Přírodovědecké fakultě Masarykovy univerzity byl 10. března 2011, měsíc před 60. výročím jeho úmrtí (12. 4. 1951) uspořádán složkami Jednoty českých matematiků a fyziků v součinnosti s vedením fakulty seminář, jako vzpomínka na matematika a fyzika Bohuslava Hostinského., Martin Černohorský., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

46. C*-algebras have a quantitative version of Pełczyński's property (V)

Creator:
Krulišová, Hana
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, Pełczyński's property (V), $C^*$-algebra, Grothendieck property, 13, and 51
Language:
English
Description:
A Banach space $X$ has Pełczyński's property (V) if for every Banach space $Y$ every unconditionally converging operator $T\colon X\to Y$ is weakly compact. H. Pfitzner proved that $C^*$-algebras have Pełczyński's property (V). In the preprint (Krulišová, (2015)) the author explores possible quantifications of the property (V) and shows that $C(K)$ spaces for a compact Hausdorff space $K$ enjoy a quantitative version of the property (V). In this paper we generalize this result by quantifying Pfitzner's theorem. Moreover, we prove that in dual Banach spaces a quantitative version of the property (V) implies a quantitative version of the Grothendieck property., Hana Krulišová., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

47. Cartan-Eilenberg projective, injective and flat complexes

Creator:
Zhai, Xiaorui and Zhang, Chunxia
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, komplexy (matematika), mathematics, complexes, Cartan-Eilenberg projective complex, Cartan-Eilenberg injective complex, Cartan-Eilenberg flat complex, 13, and 51
Language:
English
Description:
Let R be an associative ring with identity and F a class of R-modules. In this article: we first give a detailed treatment of Cartan-Eilenberg F complexes and extend the basic properties of the class F to the class CE(F). Secondly, we study and give some equivalent characterizations of Cartan-Eilenberg projective, injective and flat complexes which are similar to projective, injective and flat modules, respectively. As applications, we characterize some classical rings in terms of these complexes, including coherent, Noetherian, von Neumann regular rings, QF rings, semisimple rings, hereditary rings and perfect rings., Xiaorui Zhai, Chunxia Zhang., and Obsahuje seznam literatury
Rights:
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48. Časopis DVT o dějinách přírodních věd a matematiky na Univerzitě Karlově v letech 1980-1983 /

Creator:
Fajkus, Břetislav,
Type:
text and články
Subject:
Seriálové publikace. Periodika, historiografie, Univerzita Karlova, časopisy vědecké, dějiny vědy, vědy přírodní, matematika, česká periodika, Československo 1969-1989, dějepisectví, historické vědy, historici, dějiny přírodních věd, and dějiny vědeckých institucí, vysokých škol
Language:
Czech
Rights:
unknown

49. Certain decompositions of matrices over Abelian rings

Creator:
Ashrafi, Nahid, Sheibani, Marjan, and Huanyin Chen
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, weakly nil clean ring, idempotent element, nilpotent element, nil clean ring, 13, and 51
Language:
English
Description:
A ring R is (weakly) nil clean provided that every element in R is the sum of a (weak) idempotent and a nilpotent. We characterize nil and weakly nil matrix rings over abelian rings. Let R be abelian, and let n 2 N. We prove that Mn(R) is nil clean if and only if R/J(R) is Boolean and Mn(J(R)) is nil. Furthermore, we prove that R is weakly nil clean if and only if R is periodic; R/J(R) is Z3, B or Z3 B where B is a Boolean ring, and that Mn(R) is weakly nil clean if and only if Mn(R) is nil clean for all n > 2., Nahid Ashrafi, Marjan Sheibani, Huanyin Chen., and Seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

50. Ck-regularity for the ∂-equation with a support condition

Creator:
Khidr, Shaban and Abdelkader, Osama
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, equation, q-convexity, Ck-estimate, 13, and 51
Language:
English
Description:
Let D be a Cd q-convex intersection, d > 2, 0 6 q 6 n − 1, in a complex manifold X of complex dimension n, n > 2, and let E be a holomorphic vector bundle of rank N over X. In this paper, Ck-estimates, k = 2, 3, . . . ,1, for solutions to the -equation with small loss of smoothness are obtained for E-valued (0, s)-forms on D when n − q 6 s 6 n. In addition, we solve the -equation with a support condition in Ck-spaces. More precisely, we prove that for a -closed form f in Ck 0,q(X \ D,E), 1 6 q 6 n − 2, n > 3, with compact support and for " with 0 < " < 1 there exists a form u in Ck−ε 0,q−1(X \ D,E) with compact support such that u = f in X \ D. Applications are given for a separation theorem of Andreotti-Vesentini type in Ck-setting and for the solvability of the -equation for currents., Shaban Khidr, Osama Abdelkader., and Seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public