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41.
42.
In this paper we show that a quasi-forest is shellable if and only if its h-triangle satisfies ${h_{i,j}(\Delta)=0 \quad \forall i, \forall j >1 }$ . In addition, it will be shown that a quasi-forest is sequentially Cohen-Macaulay if and only if it is shellable. 相似文献
43.
Let M1,…,Mn be right modules over a ring R. Suppose that the endomorphism ring of each module Mi has at most two maximal right ideals. Is it true that every direct summand of M1⊕?⊕Mn is a direct sum of modules whose endomorphism rings also have at most two maximal right ideals? We show that the answer is negative in general, but affirmative under further hypotheses. The endomorphism ring of uniserial modules, that is, the modules whose lattice of submodules is linearly ordered under inclusion, always has at most two maximal right ideals, and Pavel P?íhoda showed in 2004 that the answer to our question is affirmative for direct sums of finitely many uniserial modules. 相似文献
44.
Amirhossein Hajihosseini Farzaneh Maleki Gholam Reza Rokni Lamooki 《Chaos, solitons, and fractals》2011,44(11):1004-1019
A class of recurrent neural networks is constructed by generalizing a specific class of n-neuron networks. It is shown that the newly constructed network experiences generic pitchfork and Hopf codimension one bifurcations. It is also proved that the emergence of generic Bogdanov–Takens, pitchfork–Hopf and Hopf–Hopf codimension two, and the degenerate Bogdanov–Takens bifurcation points in the parameter space is possible due to the intersections of codimension one bifurcation curves. The occurrence of bifurcations of higher codimensions significantly increases the capability of the newly constructed recurrent neural network to learn broader families of periodic signals. 相似文献
45.
46.
Rasoul Ahangari Maleki 《代数通讯》2017,45(2):514-520
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48.
Let G be a graph with vertex set V. A set ${D \subseteq V}$ is a total restrained dominating set of G if every vertex in V has a neighbor in D and every vertex in ${V \setminus D}$ has a neighbor in ${V \setminus D}$ . The minimum cardinality of a total restrained dominating set of G is called the total restrained domination number of G, and is denoted by γ tr (G). In this paper, we prove that if G is a connected graph of order n ≥ 4 and minimum degree at least two, then ${\gamma_{tr}(G) \leq n-\sqrt[3]{n \over 4}}$ . 相似文献
49.
In this paper we first recall some definitions and results of fuzzy plane geometry, and then introduce some definitions in
the geometry of two-dimensional fuzzy linear programming (FLP). After defining the optimal solution based on these definitions,
we use the geometric approach for obtaining optimal solution(s) and show that the algebraic solutions obtained by Zimmermann
method (ZM) and our geometric solutions are the same. Finally, numerical examples are solved by these two methods. 相似文献
50.
Mohammad H. Maleki Sanaz Abbasi Majid Vaezzade Amir Asgari 《Optical and Quantum Electronics》2014,46(9):1149-1155
In this study, anti-reflection (AR) \(\hbox {SiO}_{2}/ \hbox {ZrO}_{2}\) thin films with 3-layers were designed and fabricated by the essential Macleod software and physical vapor deposition, respectively. In order to improve the optical and physical properties of the prepared samples, laser shock peening (LSP) technique was applied. For this purpose, an Argon Fluoride Excimer laser \((\lambda =193 \,\text {nm})\) with 110 and 240 mJ energies and 1 Hz frequency at different pulses was used. The effect of LSP method in improving transmissions and laser damage thresholds of the prepared samples was proved by using UV–Vis–IR spectroscopy in the wavelength range of 400–1200 nm and international standard ISO11254 at 1064 nm. In addition, scanning electron microscopy was used to check the effect of applying LSP. 相似文献