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151.
Revenue management (RM) enhances the revenues of a company by means of demand-management decisions. An RM system must take into account the possibility that a booking may be canceled, or that a booked customer may fail to show up at the time of service (no-show). We review the Passenger Name Record data mining based cancellation rate forecasting models proposed in the literature, which mainly address the no-show case. Using a real-world dataset, we illustrate how the set of relevant variables to describe cancellation behavior is very different in different stages of the booking horizon, which not only confirms the dynamic aspect of this problem, but will also help revenue managers better understand the drivers of cancellation. Finally, we examine the performance of the state-of-the-art data mining methods when applied to Passenger Name Record based cancellation rate forecasting. 相似文献
152.
T. Martínez F. Aguilar J. Lartigue M. Navarrete L. A. Cuapio C. López O. Y. Morales 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):365-370
Due to large consumption of tobacco in Mexico and in order to complement previous work performed by total reflection X-ray
fluorescence, the present study has determined 15 elements by INAA in 9 cigarettes brands being marketed in Mexico. As a part
of a Quality Control Program, NIST standard reference materials (SRM) and an IAEA reference material were analyzed to confirm
the accuracy and reproducibility. Average of As and Cd were 0.56 and 1.15 μg·g−1, respectively, in the range of those of foreign brands. 相似文献
153.
In this paper we establish a decomposition theorem for a positive regular measure on an orthoalgebra with values in an ordered topological group not necessarily commutative. We deduce from it the A. D. Alexandroff’s classical first decomposition theorem and we discuss its uniqueness in the setting of metric spaces. 相似文献
154.
Maria BURGOS ;E Amin KAIDI ;Antonio Morales CAMPOY ;Antonio M. PERALTA ;Maribel RAMIREZ 《数学学报(英文版)》2008,24(2):185-200
We revise the notion of von Neumann regularity in JB^*-triples by finding a new characterisation in terms of the range of the quadratic operator Q(a). We introduce the quadratic conorm of an element a in a JB^*-triple as the minimum reduced modulus of the mapping Q(a). It is shown that the quadratic conorm of a coincides with the infimum of the squares of the points in the triple spectrum of a. It is established that a contractive bijection between JBW^*-triples is a triple isomorphism if, and only if, it preserves quadratic conorms. The continuity of the quadratic conorm and the generalized inverse are discussed. Some applications to C^*-algebras and von Neumann algebras are also studied. 相似文献
155.
156.
In recent years, significant research in the field of electrochemistry was developed. The performance of electrical devices, depending on the processes of the electrolytes, was described and the physical origin of each parameter was established. However, the influence of the irregularity of the electrodes was not a subject of study and only recently this problem became relevant in the viewpoint of fractional calculus. This paper describes an electrolytic process in the perspective of fractional order capacitors. In this line of thought, are developed several experiments for measuring the electrical impedance of the devices. The results are analyzed through the frequency response, revealing capacitances of fractional order that can constitute an alternative to the classical integer order elements. Fractional order electric circuits are used to model and study the performance of the electrolyte processes. 相似文献
157.
C. Aguilar‐Lugo R. Le Lagadec Alexander D. Ryabov G. Cedillo Valverde S. Lopez Morales L. Alexandrova 《Journal of polymer science. Part A, Polymer chemistry》2009,47(15):3814-3828
Cationic substitutionally inert cyclometalated ruthenium (II) and osmium (II) complexes, ([Mt(o‐C6H4‐2‐py)(LL)2]PF6), where LL‐1,10‐phenanthroline (phen) or 2,2′‐bipyridine (bipy), were used for radical polymerization of styrene. Gradual modification of the complexes within the series allowed comparison of the catalytic activity and the redox properties. There was no correlation between the reducing powers of the complexes and their catalytic activities. The osmium compound of the lowest reduction potential was not active. All the ruthenium complexes catalyzed the polymerization of styrene in a controlled manner; but the level of control and the catalytic activity were different under the same polymerization conditions. [Ru(o‐C6H4‐2‐py)(phen)2]PF6 demonstrated the best catalytic performance though its redox potential was the highest. It catalyzed the “living” polymerization with a reasonable rate at a catalyst‐to‐initiator ratio of 0.1. 1 equiv. of Al(OiPr)3 accelerated the polymerization and improved the control, but higher amount of Al(OiPr)3 did not speed up the polymerization and moved the process into the uncontrollable regime. Under the most optimal conditions, the controlled polymerization occurs fast without any additive and the catalyst degradation. Added free ligands inhibited the polymerization suggesting that the catalytically active ruthenium intermediates are generated via the reversible dechelation of bidentate phen or bipy ligands. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3814–3828, 2009 相似文献
158.
159.
Jesus Lerma Tariq Khraishi Yu-Lin Shen Brian D. Wirth 《Mechanics Research Communications》2003,30(4):325-334
Analytical solutions for the displacement and stress fields due to a misfit particle in a host matrix can be difficult to obtain, especially for complex particle geometries. In this work, we present a numerical method for finding such fields in the case of infinitely-long particles. The method is based on discretizing the continuous misfit region between the particle and matrix into local misfit regions consisting of interstitial dislocation loops. The results presented here indicate very good agreement with analytical solutions and better convergence with increasing loop density. 相似文献
160.
Serxio I. Arias-Barros Antonio Cid Luis García-Río Juan C. Mejuto Jorge Morales 《Colloid and polymer science》2010,288(2):217-221
The influence of different polyethylene glycol (PEG) on the percolation of the ternary system composed by sodium bis(2-ethylhexyl)
sulfosuccinate (AOT) + isooctane + water has been studied. The additives used were chosen on the basis of its chain length
(the number of polymeric units). In all cases, we observed a decrease in the percolation threshold on increasing the amount
of PEG added to the AOT microemulsions. We observed a correlation between the effect exerted by the additive upon the percolation
temperature and its chain length. Moreover, a relationship between the percolation temperature and the additive partition
coefficient between 1-octanol and water (logP) was found. Both of them proved the importance of the inclusion of the additives into the microemulsion interface to explain
their influence upon the percolative phenomenon. Such inclusion modified the properties of the AOT film, facilitating the
exchange of matter between droplets. 相似文献