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101.
In this paper we develop the main aspects of the Bohman–Korovkin theorem on approximation of continuous functions with the use of A-statistical convergence and matrix summability method which includes both convergence and almost convergence. Since statistical convergence and almost convergence methods are incompatible we conclude that these methods can be used alternatively to get some approximation results. 相似文献
102.
103.
104.
Analytical solutions for two-dimensional Markov processes suffer from the state space explosion problem. Two stage tandem networks are effectively used for analytical modelling of various communication and computer systems which have tandem system behaviour. Performance evaluation of tandem systems with feedbacks can be handled with these models. However, because of the numerical difficulties caused by large state spaces, considering server failures and repairs at the second stage employing multiple servers has not been possible. The solution proposed in this paper is approximate with a high degree of accuracy. Using this approach, two stage open networks with multiple servers, break downs, and repairs at the second stage as well as feedback can be modelled as three-dimensional Markov processes and solved for performability measures. Results show that, unlike other approaches such as spectral expansion, the steady state solution is possible regardless of the number of servers employed. 相似文献
105.
Nevzat Karaday ükriye akmak Mustafa Odabaolu Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):o303-o305
The title 4,4′‐disubstituted diphenyl‐1,3‐triazines, C14H15N3, (I), C12H9ClFN3, (II), and C13H12FN3, (III), each contain a triazene group (–N=N—NH–) having an extended conformation. The dihedral angles between the two benzene rings in (I), (II) and (III) are 4.3, 3.4 and 6.5°, respectively. The molecules are almost entirely planar, with maximum deviations from the mean planes of 0.1087 (2), −0.1072 (7) and 0.1401 (3) Å, respectively. In each compound, the molecules are linked by N—H⋯N hydrogen bonds to form chains and pack similarly in the crystal structures. 相似文献
106.
Serkan Soylu Murat Ta Hanife Sarao
lu Hümeyra Bat Nezihe alkan Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o115-o117
The structure of the title compound, C16H16N2O2, consists of a dimeric arrangement around an inversion centre of acetamidine molecules linked via O—H⋯N hydrogen bonds. There are also H⋯π‐ring interactions. All these interactions result in the formation of infinite chains parallel to the (101) axis. The oxime group has an E conformation. 相似文献
107.
Betül en Serap Alp Gülsiye
ztürk Muhittin Aygün Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o223-o224
Molecules of the title compound, C24H19NO6S, adopt the Z configuration and have a distorted tetrahedral geometry around the S atom. The oxazolone, 2‐phenyl and methoxyphenyl rings are approximately coplanar. The C atom between the methoxyphenyl and oxazolone rings displays a distorted trigonal bonding geometry. Pairs of molecules are linked into dimers through weak C—H⋯O hydrogen bonds. 相似文献
108.
Onur ahin Orhan Büyükgüngr Selami amaz Nurhan Gümrüküolu Cihan Kantar 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o643-o646
The title compounds, C10H12N4, (I), and C9H10N4, (II), have been synthesized and characterized both spectroscopically and structurally. The dihedral angles between the triazole and benzene ring planes are 26.59 (9) and 42.34 (2)°, respectively. In (I), molecules are linked principally by N—H⋯N hydrogen bonds involving the amino NH2 group and a triazole N atom, forming R44(20) and R24(10) rings which link to give a three‐dimensional network of molecules. The hydrogen bonding is supported by two different C—H⋯π interactions from the tolyl ring to either a triazole ring or a tolyl ring in neighboring molecules. In (II), intermolecular hydrogen bonds and C—H⋯π interactions produce R34(15) and R44(21) rings. 相似文献
109.
Cengiz Arıcı Dinçer Ülkü Mecit Aksu Orhan Atakol 《Journal of chemical crystallography》2003,33(11):825-829
The title compound, forms crystals which are the orthorhombic system, space group P2
12121, with unit cell dimensions a = 10.3928(12) Å, b = 14.6298(13) Å, c = 15.9514(11) Å, V = 2425.3(4) Å3. The cell contains four molecules. The structure is a heteronuclear dimeric complex with ZnII and CdII ions. The coordination around the ZnII ion is distorted square–pyramid and the CdII ion is distorted tetrahedral coordination. The Zn·sCd distance is 3.3594(7) Å. 相似文献
110.
Mustafa OdabasÛoglu igdem Albayrak Orhan Büyükgüngr Helmut Goesmann 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):o234-o236
The title compound, C17H18ClN3O4, adopts the keto–amine tautomeric form and displays an intramolecular N—H⋯O hydrogen bond [N⋯O = 2.639 (2) Å]. The configuration around the azo N=N double bond is trans, and the dihedral angle between the planes of the two aromatic rings is 20.5 (2)°. The molecules are linked by O—H⋯O hydrogen bonds to form a three‐dimensional network. 相似文献