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111.
112.
Since short cycles are (empirically) detrimental to message passing, determining the girth of a given code is of interest
in coding theory. Halford et al. studied codes which do not have a 4-cycle-free Tanner graph representation. It is natural
to then ask which codes must have girth 8. In this paper, a new necessary condition is derived for codes to have girth 8.
Halford et al. made statements about the girth of high rate well known codes but the girth of lower rate codes remain open.
In this work, we investigate girth of low rate Reed–Muller, BCH and Reed–Solomon codes. 相似文献
113.
Mahdi Sadeghi Milad Enferadi Hojjat Nadi Claudio Tenreiro 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(1):141-144
Amongst the various radioisotopes of molybdenum, 93mMo in its no-carrier added form might be a potential candidate radionuclide in the field of nuclear medicine due to its suitable
half-life (T
1/2 = 6.85 h) and for its intense gamma line at 263.14 keV. Aim of the presented study is to compare the calculated cross sections
for the production of 93mMo incident proton energy up to 30 MeV, theoretical calculation of production yield and calculation of target thickness requirement.
Also, deposition of 93NbO2 on Cu substrate was carried out via two special sedimentation methods for the production of 93mMo and a simple and selective extraction of molybdenum was described. 相似文献
114.
J. Sadeghi M. R. Pahlavani H. Farahani 《International Journal of Theoretical Physics》2010,49(4):914-920
Gravitational perturbation in AdS
4, decomposed into axial and polar perturbations that have different parities. After imposing geometric perturbation in to
the spherical, symmetric and static metric of AdS
4, we can calculate the possible spectrum of frequencies around the static configuration. This spectrum relates to the boundary
conditions imposed at spatial infinity (r=∞) and will be implied by the wave function’s behavior at
x=\fracp2x=\frac{\pi}{2}
or y=1. At the end we write down the first order raising and lowering operators from the second order Schr?dinger equation to
study the supersymmetry model and check whether we have supersymmetric partners or no. After finding the H
1 and the partner H
2, we check the supersymmetry. At the end, we find the potentials to confirm the shape invariance condition and also the supercharges
and their commutative relations are studied. 相似文献
115.
In this paper we generalized the charged open string attached both ends to the same branes to the case where charged open superstring is stretched between two different D-branes. These branes involve constant background two-dimensions magnetic field. We focus our attention to type II superstring and consider the interaction between branes. We obtain relation between string charge and the separation of two D-branes. Further more we find the modified normal ordering constant and mode expansions of superstring. 相似文献
116.
Taghizadeh Mohammad Javad Karimi Homman Abandansari Hamid Sadeghi 《Research on Chemical Intermediates》2016,42(12):8201-8215
Research on Chemical Intermediates - VO2(picolinichydrazone) complex as a catalyst was stabilized on a SBA-15 mesoporous silica as a catalytic support by using (3-chloropropyl)triethoxysilane as a... 相似文献
117.
Gas-chromatographic fatty-acid fingerprints and partial least squares modeling as a basis for the simultaneous determination of edible oil mixtures 总被引:10,自引:0,他引:10
Hajimahmoodi M Vander Heyden Y Sadeghi N Jannat B Oveisi MR Shahbazian S 《Talanta》2005,66(5):1108-1116
Partial least squares modeling and gas-chromatographic fatty-acid fingerprints are reported as a method for the simultaneous determination of cottonseed, olive, soybean and sunflower edible oil mixtures. In this work, two sets of three- and four-component combinations of oils were prepared, hydrolyzed and the obtained free fatty acids analyzed by gas chromatography (GC) without any further derivatization. The normalized percentages of the myristic (14:0), palmitic (16:0), palmitoleic (16:1), stearic (18:0), oleic (18:1), linoleic (18:2) and linolenic (18:3) acids were chromatographically measured in samples and used for constructing calibration matrix. The cross-validation method was used to select the number of factors and the proposed methods were validated by using two sets of synthetic oil mixture samples. The relative standard error for each oil in mixture samples was less than 10%. This approach allows determining possible adulteration in each of the four edible oils. 相似文献
118.
H. Loghmani-Khouzani M. M. Sadeghi M. H. Ghorbani 《Journal of the Iranian Chemical Society》2006,3(4):360-366
Some α-oxoketene-N,S- and N,N-acetals were selectively synthesized in good to excellent yields by the reaction of 1,1-dimethoxy-4,4-di(methylthio)-3-buten-2-one with primary and secondary amines under moderate conditions. Secondary amines in reaction with α-oxoketene dithioacetal yielded double-substitution products exclusively, whereas primary amines under the same conditions yielded the mono-substituted products as exclusive or main products. 相似文献
119.
Mahdi Alipour Mohammad Amin Torabi Mohammad Sareban Hadi Lashini Ehsan Sadeghi Abolfazl Fazaeli 《基于设计的结构力学与机械力学》2020,48(5):525-541
AbstractIn this article, we investigated the effect of martensite morphology on the mechanical properties and formability of dual phase steels. At first, three heat treatment cycles were subjected to a low-carbon steel to produce ferrite–martensite microstructure with martensite morphology of blocky-shaped, continuous, and fibrous. Tensile tests were then carried out so as to study mechanical properties, particularly the strength and strain hardening behavior of dual phase steels. In order to study the formability of dual phase samples, Forming Limit Diagram was obtained experimentally and numerically. Experimental forming limit diagram was obtained using Nakazima forming test, while Finite Element Method was utilized to numerically predict the forming limit diagram. The results indicated that the dual phase samples with fibrous martensite morphology had the highest tensile properties and strain rate hardening out of the three different microstructures. Blocky-shaped martensite morphology, on the other hand, had the worst mechanical properties. The study of the strain hardening behavior of dual phase sample by Kocks–Mecking-type plots, evinced two stages of strain hardening for all specimens with different microstructures: stages III and IV. The forming limit diagram of dual phase steels also proved that samples with fibrous martensite morphology had the best formability compared to other two microstructures. The simulated forming limit diagram manifested that there is a good agreement between experimental results and those obtained by FEM. 相似文献
120.
Afima Abdullah Shidfar Ali A. Sadeghi 《Journal of Mathematical Analysis and Applications》1986,120(2)
Some methods for solving the differential equation of the nonlinear anharmonic motion of an oscillator is here considered. The different given solutions are compared. 相似文献