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521.
Morteza?EbneshahrashoobEmail author Tangan?Gao Mengnien?Wu 《Methodology and Computing in Applied Probability》2005,7(4):459-471
Waiting time random variables and related scan statistics have a wide variety of interesting and useful applications. In this
paper, exact distribution of discrete scan statistics for the cases of homogeneous two-state Markov dependent trials as well
as i.i.d. Bernoulli trials are discussed by utilizing probability generating functions. A simple algorithm has been developed
to calculate the distributions. Numerical results show that the algorithm is very efficient and is capable of handling large
problems.
AMS 2000 Subject Classification 60J22, 60E05, 60J10 相似文献
522.
Characterization of solvation properties of lipid bilayer membranes in liposome electrokinetic chromatography 总被引:2,自引:0,他引:2
The nature of solute interactions with biomembrane-like liposomes, made of naturally occurring phospholipids and cholesterol, was characterized using electrokinetic chromatography (EKC). Liposomes were used as a pseudo-stationary phase in EKC that provided sites of interactions for uncharged solutes. The retention factors of uncharged solutes in liposome EKC are directly proportional to their liposome-water partition coefficients. Linear solvation energy relationship (LSER) models were developed to unravel the contributions from various types of interactions for solute partitioning into liposomes. Size and hydrogen bond acceptor strength of solutes are the main factors that determine partitioning into lipid bilayers. This falls within the general behavior of solute partitioning from an aqueous into organic phases such as octanol and micelles. However, there exist subtle differences in the solvation properties of liposomes as compared to those of octanol and various micellar pseudo-phases such as aggregates of sodium dodecyl sulfate (SDS), sodium cholate (SC), and tetradecylammonium bromide (TTAB). Among these phases, the SDS micelles are the least similar to the liposomes, while octanol, SC, and TTAB micelles exhibit closer solvation properties. Subsequently, higher correlations are observed between partitioning into liposomes and the latter three phases than that into SDS. 相似文献
523.
The separation and characterization of human apolipoproteins and their isoforms was investigated using capillary electrophoresis (CE) in combination with mass spectrometry (MS). The focus of these analyses was the major protein constituents of plasma high-density lipoproteins, apolipoprotein A-I and A-II. Using aqueous buffers in CE, no separation between apolipoprotein A-I and A-II was observed. With the addition of 10-20% acetonitrile, however, the two species could be separated. Furthermore, multiple peaks for each of the apolipoprotein species were observed under these CE conditions. In order to identify and characterize the components, these separations were then coupled with online mass spectrometric detection (CE-MS). Our CE-MS results suggest that the multiple components observed in the acetonitrile-containing CE separation appear to be oxidized forms of the proteins in addition to native forms of the apolipoprotein A-I and A-II. These data are in agreement with previous reports that the methionine residues of the high-density lipoproteins (HDLs) are sensitive to oxidation, which in turn, alters their lipid binding characteristics and secondary structure. In addition to oxidized forms of the proteins, apolipoprotein A-II contained additional components, which varied in mass by 128 Da. The structural differences between these components were determined by proteolytic digestion and tandem MS. Using these techniques, we determined that these components were due to truncation of the C-terminal glutamine amino acid residue on apolipoprotein A-II. These results demonstrate that CE in combination with MS is a promising technique for screening and characterizing isomers of plasma apolipoproteins. 相似文献
524.
Morteza Mohseni 《The European Physical Journal C - Particles and Fields》2008,56(4):607-612
We investigate the motion of a spinning test particle in a spatially-flat FRW-type space-time in the framework of the Einstein–Cartan
theory. The space-time has a torsion arising from a spinning fluid filling the space-time. We show that, for spinning particles
with non-zero transverse spin components, the torsion induces a precession of the particle spin around the direction of the
spin of the fluid. We also show that a charged spinning particle moving in a torsion-less spatially-flat FRW space-time in
the presence of a uniform magnetic field undergoes a precession of a different character. 相似文献
525.
Morteza Moniri 《Mathematical Logic Quarterly》2003,49(4):425-427
IPV is the intuitionistic theory axiomatized by Cook's equational theory PV plus PIND on NP‐formulas. Two extensions of IPV were introduced by Buss and by Cook and Urquhart by adding PIND for formulas of the form A(x) ∨ B, respectively ¬¬A(x), where A(x) is NP and x is not free in B. Cook and Urquhart posed the question of whether these extensions are proper. We show that in each of the two cases the extension is proper unless the polynomial hierarchy collapses. 相似文献
526.
Jila Talat-Mehrabad Morteza Khosravi Nasser Modirshahla Mohammad A. Behnajady 《Research on Chemical Intermediates》2016,42(2):595-609
In this study, we successfully prepared pure, mono-doped, and Ag, Mg co-doped TiO2 nanoparticles using the sol–gel method, with titanium tetraisopropoxide as the Ti source. The prepared samples were characterized by X-ray powder diffraction (XRD), specific surface area and porosity (BET and BJH) measurement, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, photoluminescence, and energy dispersive X-ray spectroscopy techniques. The XRD data showed that the prepared nanoparticles had the same crystals structures as the pure TiO2. Also, DRS results indicated that the band gap of co-doped photocatalyst was smaller than that of the monometallic and undoped TiO2 and that there was a shift in the absorption band towards the visible light region. Furthermore, the photocatalytic activity of the prepared catalysts was evaluated by the degradation of C.I. Acid Red 27 in aqueous solution under visible light irradiation. The results showed that Ag (0.08 mol%), Mg (0.2 mol%) co-doped TiO2 had the highest photoactivity among all samples under visible light. It was concluded that co-doping of the Ag and Mg can significantly improve the photocatalytic activity of the prepared photocatalysts, due to the efficient inhibition of the recombination of photogenerated electron–hole pairs. The optimum calcination temperature and time were 450 °C and 3 h, respectively. 相似文献
527.
Morteza Lalmazloumian Kuan Yew Wong Kannan Govindan Devika Kannan 《Annals of Operations Research》2016,240(2):435-470
Supply chain planning as one of the most important processes within the supply chain management concept, has a great impact on firms’ success or failure. This paper considers a supply chain planning problem of an agile manufacturing company operating in a build-to-order environment under various kinds of uncertainty. An integrated optimization approach of procurement, production and distribution costs associated with the supply chain members has been taken into account. A robust optimization scenario-based approach is used to absorb the influence of uncertain parameters and variables. The formulation is a robust optimization model with the objective of minimizing the expected total supply chain cost while maintaining customer service level. The developed multi-product, multi-period, multi-echelon robust mixed-integer linear programming model is then solved using the CPLEX optimization studio and guidance related to future areas of research is given. 相似文献
528.
The Orienteering Problem (OP) is a well-known variant of the Traveling Salesman Problem. In this paper, a novel Greedy Randomized Adaptive Search Procedure (GRASP) solution is proposed to solve the OP. The proposed method is shown to outperform state-of-the-art heuristics for the OP in producing high quality solutions. In comparison with the best known solutions of standard benchmark instances, the method can find the optimal or the best known solution of about 70 % of the instances in a reasonable time, which is about 17 % better than the best known approach in the literature. Moreover, a significant improvement is achieved on the solution of two standard benchmark instances. 相似文献
529.
This paper introduces the concept of fuzzy projection of a fuzzy number on a set of fuzzy numbers based on r-cut approach. It is proved that the projection of a fuzzy number on the set of all fuzzy numbers is itself and under a special metric, the proposed fuzzy projection is a non-expansive mapping. By using this definition, the concept of fuzzy linear projection equation is defined and to solve it, a numerical method is applied. Based on the proposed algorithm and as an important application, two different types of system of fuzzy linear equations with fuzzy variables are solved. Numerical results illustrate the applicabilities of proposed approach. 相似文献
530.