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562. A characterization of the linear groups $L_{2}(p)$
- Creator:
- Khalili Asboei, Alireza and Iranmanesh, Ali
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- element order, set of the numbers of elements of the same order, and linear group
- Language:
- English
- Description:
- Let $G$ be a finite group and $\pi _{e}(G)$ be the set of element orders of $G$. Let $k \in \pi _{e}(G)$ and $m_{k}$ be the number of elements of order $k$ in $G$. Set ${\rm nse}(G):=\{m_{k}\colon k \in \pi _{e}(G)\}$. In fact ${\rm nse}(G)$ is the set of sizes of elements with the same order in $G$. In this paper, by ${\rm nse}(G)$ and order, we give a new characterization of finite projective special linear groups $L_{2}(p)$ over a field with $p$ elements, where $p$ is prime. We prove the following theorem: If $G$ is a group such that $|G|=|L_{2}(p)|$ and ${\rm nse}(G)$ consists of $1$, $p^{2}-1$, $p(p+\epsilon )/2$ and some numbers divisible by $2p$, where $p$ is a prime greater than $3$ with $p \equiv 1$ modulo $4$, then $G \cong L_{2}(p)$.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
563. A characterization of the Riemann extension in terms of harmonicity
- Creator:
- Bejan, Cornelia-Livia and Eken, Şemsi
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, mathematics, harmonické tenzorové pole, Semi-Riemannian manifold, cotangent bundle, natural Riemann extension, harmonic tensor field, 13, and 51
- Language:
- English
- Description:
- If (M,∇) is a manifold with a symmetric linear connection, then T*M can be endowed with the natural Riemann extension g¯ (O. Kowalski and M. Sekizawa (2011), M. Sekizawa (1987)). Here we continue to study the harmonicity with respect to g¯g¯ initiated by C. L.Bejan and O.Kowalski (2015). More precisely, we first construct a canonical almost para-complex structure PP on (T*M, g¯) and prove that P is harmonic (in the sense of E.Garciá-Río, L.Vanhecke and M. E.Vázquez-Abal (1997)) if and only if g¯ reduces to the classical Riemann extension introduced by E.M. Patterson and A.G. Walker (1952)., Cornelia-Livia Bejan, Şemsi Eken., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
564. A characterization of totally $\eta$-umbilical real hypersurfaces and ruled real hypersurfaces of a complex space form
- Creator:
- Kon, Mayuko
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- real hypersurface, totally $\eta $-umbilical real hypersurface, and ruled real hypersurface
- Language:
- English
- Description:
- We give a characterization of totally $\eta $-umbilical real hypersurfaces and ruled real hypersurfaces of a complex space form in terms of totally umbilical condition for the holomorphic distribution on real hypersurfaces. We prove that if the shape operator $A$ of a real hypersurface $M$ of a complex space form $M^n(c)$, $c\neq 0$, $n\geq 3$, satisfies $g(AX,Y)=ag(X,Y)$ for any $X,Y\in T_0(x)$, $a$ being a function, where $T_0$ is the holomorphic distribution on $M$, then $M$ is a totally $\eta $-umbilical real hypersurface or locally congruent to a ruled real hypersurface. This condition for the shape operator is a generalization of the notion of $\eta $-umbilical real hypersurfaces.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
565. A characterization of weighted $(LB)$-spaces of holomorphic functions having the dual density condition
- Creator:
- Wolf, Elke
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- $(LB)$-spaces, weighted spaces of holomorphic functions, and dual density condition
- Language:
- English
- Description:
- We characterize when weighted $(LB)$-spaces of holomorphic functions have the dual density condition, when the weights are radial and grow logarithmically.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
566. A chart preserving the normal vector and extensions of normal derivatives in weighted function spaces
- Creator:
- Schuhmache, Katrin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chart, coordinate transformation, normal vector, normal derivative, extension theorem, and Muckenhoupt weight
- Language:
- English
- Description:
- Given a domain $\Omega $ of class $C^{k,1}$, $k\in \Bbb N $, we construct a chart that maps normals to the boundary of the half space to normals to the boundary of $\Omega $ in the sense that $(\partial- {\partial x_n})\alpha (x',0)= - N(x')$ and that still is of class $C^{k,1}$. As an application we prove the existence of a continuous extension operator for all normal derivatives of order 0 to $k$ on domains of class $C^{k,1}$. The construction of this operator is performed in weighted function spaces where the weight function is taken from the class of Muckenhoupt weights.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
567. A cheap chlorophyll a fluorescence imaging system
- Creator:
- Lootens, P. and Vandecasteele, P.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- diuron and Zea mays
- Language:
- Multiple languages
- Description:
- A cheap chlorophyll (Chl) a fluorescence imaging system was developed for measuring leaf areas of 30×45 cm. Uniform saturating irradiances were created using CuSO4 filtered radiation from stroboscopes. The system was tested using maize leaves treated with diuron. Comparison was made with a small-area-measuring pulse amplified modulation Chl fluorometer. and P. Lootens, P. Vandecasteele.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
568. A child burial with a necklace from the Triangle cemetery in Prague-Střešovice
- Creator:
- Frolíková, Drahomíra, Ottenwelter, Estelle, and Barčáková, Ludmila
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Bohemia, cemetery, 10th century, kaptorga, gombiks, beads, SEM/EDS analysis, Čechy, pohřebiště, 10. století, gombíky, korálky, and SEM/EDS analýzy
- Language:
- Czech
- Description:
- The Triangle cemetery in Prague-Střešovice was the only preserved part of the great burial site from the 9th–10th century AD; this site was partially destroyed beginning in the 18th century by the extraction of clay for the Strahov brick factory. A total of 49 graves, all dated to the 10th century, were uncovered in the preserved part of the cemetery in 2012. Children’s grave no. 16 was the richest of the children’s graves and the second richest of all graves in the cemetery. A total of 19 silver jewels were found in the grave: kaptorga – amulet container, beads, hollow spherical pendants – gombiks. A technical study was performed to describe the construction of the different types of jewels and identify the material used to manufacture them. The artefacts were examined with a stereomicroscope, subjected to X-ray radiography and observed and analysed with scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM/EDS). A replica provided practical information about the time of realisation of each type of jewel. Analogies from the technical and thematic points of view were further searched. The set of jewellery comes from the production of the Prague workshop which enriched the tradition of Great Moravian jewellery with new elements inspired by cultural influences from the west, east and south. and Pohřebiště Triangl bylo jedinou zachovanou částí velkého středohradištního pohřebiště ničeného od 18. století těžbou hlíny pro strahovskou cihelnu. V poloze Triangl bylo v roce 2012 prozkoumáno 49 číslovaných hrobů s výbavou datující je do 10. století. Dětský hrob 16 byl nejbohatší z dětských pohřbů a druhý nejbohatší celkově, bylo v něm nalezeno 19 kusů stříbrných šperků – kaptorga, korálky a gombíky. Technologický rozbor šperků má za cíl poznat způsob výroby jednotlivých typů a určit suroviny použité při jejich výrobě. Předměty byly zkoumány pomocí optické stereomikroskopie, rentgenografie a elektronové rastrovací mikroskopie ve spojení s energiově disperzní spektroskopií (SEM/EDS). Byly vyhledány analogie, co se týče technologie výroby i použitých výzdobných motivů. Replika poskytuje představu o čase potřebném k výrobě každého jednotlivého typu šperku. Soubor šperků pochází z produkce pražské dílny, která tradici velkomoravského šperkařství obohatila o nové prvky inspirované kulturními vlivy ze západu, východu i jihu.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
569. A chlorophyll fluorescence analysis of the allocation of radiant energy absorbed in photosystem 2 antennae of cotton leaves during exposure to chilling
- Creator:
- Kornyeyev, D., Logan, B. A., and Holaday, A. S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- energy dissipation, Gossypium hirsutum, low temperature, and photoinhibition
- Language:
- Multiple languages
- Description:
- When dark-acclimated cotton (Gossypium hirsutum L. cv. Coker 312) leaves, pre-treated with lincomycin to inhibit chloroplast protein repair processes, were exposed to 10 °C and a PPFD of 500 μmol m-2 s-1, the proportion of excitation energy entering photochemistry (P) increased, but only to 5 % of the total energy absorbed at steady state levels of P, which were reached at 40 min of irradiation. Thermal dissipation (D) of absorbed energy increased throughout the 360 min irradiation period and accounted for the greatest portion of absorbed energy at 10 °C. When D was partitioned into constitutive (DCON), regulated (DREG), and photoinhibitory (DPI) components, it was primarily composed of DREG, the readily reversible portion of D. However, the induction of D was slow at 10 °C. Sixty minutes were required for D to reach 70 % of the energy absorbed. Considerable absorption of energy in excess of that utilized in photochemistry or dissipated thermally (designated as E) occurred, especially during induction of P and D. Over the irradiation period, the time-dependent averaged E exhibited an inverse, linear relationship with the ratio of variable (Fv) to maximum (Fm) fluorescence (PS2 efficiency) and a linear relationship with DPI. We propose that time-dependent averaged E may be useful for estimating the potential for damage to PS2 under stressful environmental conditions. and D. Kornyeyev, B. A. Logan, A. S. Holaday.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
570. A chromospheric response to pulse beam heating
- Creator:
- Heinzel, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- heliophysics and chromosphere
- Language:
- Czech
- Description:
- Starting from flare models of Karličky (Solar Phys. 130, 1990, 347), we present the timedependent numerical simulations of hydrogen plasma excitation and ionization on subsecond time scales. These scales are consistent with the spiky behaviour of the kinetic temperature produced by non-thermal electron beam pulses of very short duration. Self-consistent numerical solution of time-dependent, NLTE problem for a three-level plus continuum hydrogen atom allows us to predict theoretically the behaviour of the Hα line intensity variations on subsecond time intervals. We present the Hα temporal profiles, evaluated at the line center and in the wing, which can be qualitatively compared with some recent flare observations obtained with very high (0.1 sec) temporal resolution. and Full version of this contribution was published in Solar Phys. 135 (1991), 65.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public