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This work deals with pricing of “virtual” products, i.e., products that a retailer can supply after demand has been realized. Such products allow the retailer to avoid holding costs and ensure timely fulfillment of demand with no risk of shortage. Demand is commonly price-dependent and uncertain, and we seek to maximize each of three criteria: expected profit, the likelihood of achieving a profit target, and the profit for a given percentile. Simultaneous multiple criteria are also explored. Two forms of demand uncertainty are considered in the analysis: the multiplicative form, where, due to stochastic dominance, all the investigated profit criteria—and, in fact, any utility function of the profit—can be optimized simultaneously; and the additive form, where stochastic dominance cannot occur. Under the multiplicative form of demand, the property of stochastic dominance is shown to hold in a two-echelon supply chain (comprising both the supplier and the retailer) and in a centralized system. 相似文献
63.
64.
Shai Dekel Pencho Petrushev Tal Weissblat 《Journal of Fourier Analysis and Applications》2011,17(5):1066-1107
In this work we develop highly geometric Hardy spaces, for the full range 0<p≤1. These spaces are constructed over multi-level ellipsoid covers of ℝ
n
that are highly anisotropic in the sense that the ellipsoids can change shape rapidly from point to point and from level
to level. This generalizes previous work on anisotropic Hardy spaces where the geometry of the space was ‘fixed’ over ℝ
n
and extends Hardy spaces over spaces of homogeneous type, where the theory holds for p values that are ‘close’ to 1. 相似文献
65.
Ethylene-bridged bis(hydroxylamino-1,3,5-triazine) compounds, that may serve as tetradentate ligands, were synthesized in three steps from 2,4,6-trichloro-1,3,5-triazine. These compounds demonstrate different rotation restrictions around the C(Ar)-N bonds due to their distinctive electronic structure as apparent from their resonative contributors. A dinuclear complex Ti 2(mu-L)2(OiPr)4 (L = bis(triazine)) was synthesized where each octahedral Ti(IV) center is also bound to two isopropoxo groups. The complex rigidity is manifested in a significant deviation from planarity of the aromatic systems, and relatively long Ti-N bonds compared to mononuclear analogous complexes. Increased ligand lability in this complex brings about diminished cytotoxicity toward colon and ovarian cells. 相似文献
66.
A linearized engagement with two pursuers versus a single evader is considered, in which the adversaries’ controls are bounded and have first-order dynamics and the pursuers’ intercept times are equal. Wishing to formulate the engagement as a zero-sum differential game, a suitable cost function is proposed and validated, and the resulting optimization problem and its solution are presented. Construction and analysis of the game space is shown, and the players’ closed-form optimal controls are derived for the case of two “strong” pursuers. The results are compared to those of a 1-on-1 engagement with a “strong” pursuer, and it is shown that the addition of a second pursuer enlarges the capture zone and introduces a new singular zone to the game space, in which the pursuers can guarantee equal misses, regardless of the evader’s actions. Additionally, it is concluded that in the regular zones the closed-form optimal pursuit strategies are unchanged compared to two 1-on-1 engagements, whereas the optimal evasion strategy is more complex. Several simulations are performed, illustrating the adversaries’ behavior in different regions of the game space. 相似文献
67.
We demonstrate simultaneous phase matching of two different nonlinear processes, using a noncollinear interaction in periodically poled crystal with single grating. The noncollinear scheme provides phase-matching solutions over continuous regions of the optical spectrum and can be used for multiple-harmonic generation as well as all-optical effects. We have demonstrated experimentally third-harmonic generation of a 3 microm pump wavelength in a noncollinear configuration using a periodically poled LiNbO3 crystal. We observed, in good agreement with theoretical calculation, very broad spectral and thermal acceptance bandwidths, as well as a relatively narrow angular bandwidth. 相似文献
68.
Electron ionization LC‐MS with supersonic molecular beams—the new concept,benefits and applications 下载免费PDF全文
Boaz Seemann Tal Alon Svetlana Tsizin Alexander B. Fialkov Aviv Amirav 《Journal of mass spectrometry : JMS》2015,50(11):1252-1263
A new type of electron ionization LC‐MS with supersonic molecular beams (EI‐LC‐MS with SMB) is described. This system and its operational methods are based on pneumatic spray formation of the LC liquid flow in a heated spray vaporization chamber, full sample thermal vaporization and subsequent electron ionization of vibrationally cold molecules in supersonic molecular beams. The vaporized sample compounds are transferred into a supersonic nozzle via a flow restrictor capillary. Consequently, while the pneumatic spray is formed and vaporized at above atmospheric pressure the supersonic nozzle backing pressure is about 0.15 Bar for the formation of supersonic molecular beams with vibrationally cold sample molecules without cluster formation with the solvent vapor. The sample compounds are ionized in a fly‐though EI ion source as vibrationally cold molecules in the SMB, resulting in ‘Cold EI’ (EI of vibrationally cold molecules) mass spectra that exhibit the standard EI fragments combined with enhanced molecular ions. We evaluated the EI‐LC‐MS with SMB system and demonstrated its effectiveness in NIST library sample identification which is complemented with the availability of enhanced molecular ions. The EI‐LC‐MS with SMB system is characterized by linear response of five orders of magnitude and uniform compound independent response including for non‐polar compounds. This feature improves sample quantitation that can be approximated without compound specific calibration. Cold EI, like EI, is free from ion suppression and/or enhancement effects (that plague ESI and/or APCI) which facilitate faster LC separation because full separation is not essential. The absence of ion suppression effects enables the exploration of fast flow injection MS‐MS as an alternative to lengthy LC‐MS analysis. These features are demonstrated in a few examples, and the analysis of the main ingredients of Cannabis on a few Cannabis flower extracts is demonstrated. Finally, the advantages of EI‐LC‐MS with SMB are listed and discussed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
69.
Photoswitching Kinetics and Phase‐Sensitive Detection Add Discriminative Dimensions for Selective Fluorescence Imaging 下载免费PDF全文
Jérôme Querard Dr. Tal‐Zvi Markus Marie‐Aude Plamont Carole Gauron Pengcheng Wang Dr. Agathe Espagne Prof. Dr. Michel Volovitch Prof. Dr. Sophie Vriz Dr. Vincent Croquette Dr. Arnaud Gautier Dr. Thomas Le Saux Prof. Dr. Ludovic Jullien 《Angewandte Chemie (International ed. in English)》2015,54(9):2633-2637
Non‐invasive separation‐free protocols are attractive for analyzing complex mixtures. To increase selectivity, an analysis under kinetic control, through exploitation of the photochemical reactivity of labeling contrast agents, is described. The simple protocol is applied in optical fluorescence microscopy, where autofluorescence, light scattering, as well as spectral crowding presents limitations. Introduced herein is OPIOM (out‐of‐phase imaging after optical modulation), which exploits the rich kinetic signature of a photoswitching fluorescent probe to increase selectively and quantitatively its contrast. Filtering the specific contribution of the probe only requires phase‐sensitive detection upon matching the photoswitching dynamics of the probe and the intensity and frequency of a modulated monochromatic light excitation. After in vitro validation, we applied OPIOM for selective imaging in mammalian cells and zebrafish, thus opening attractive perspectives for multiplexed observations in biological samples. 相似文献
70.