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71.
Product line selection and pricing decisions are critical to the profitability of many firms, particularly in today’s competitive business environment in which providers of goods and services are offering a broad array of products to satisfy customer needs.We address the problem of selecting a set of products to offer and their prices when customers select among the offered products according to a share-of-surplus choice model. A customer’s surplus is defined as the difference between his utility (willingness to pay) and the price of the product. Under the share-of-surplus model, the fraction of a customer segment that selects a product is defined as the ratio of the segment’s surplus from this particular product to the segment’s total surplus across all offered products with positive surplus for that segment.We develop a heuristic procedure for this non-concave, mixed-integer optimization problem. The procedure utilizes simulated annealing to handle the binary product selection variables, and a steepest-ascent-style procedure that relies on certain structural properties of the objective function to handle the non-concave, continuous portion of the problem involving the prices. We also develop a variant of our procedure to handle uncertainty in customer utilities. In computational studies, our basic procedures perform extremely well, producing solutions whose objective values are within about 5% of those obtained via enumerative methods. Our procedure to handle uncertain utilities also performs well, producing solutions with expected profit values that are roughly 10% higher than the corresponding expected profits from solutions obtained under the assumption of deterministic utilities. 相似文献
72.
The enolic form of cyclic compounds like 4-hydroxycoumarin,-2-pyronones,-2-pyridones and cyclohexane-1,3-diones yields malonyl heterocycles by heating withMeldrum acid.Enolisierbare Ringverbindungen vom Typ des 4-Hydroxycumarins,-2-pyronons und-2-pyridons sowie des 1,3-Cyclohexandions schließen beim Erhitzen mitMeldrumsäure Ringe zu Malonyl-heterocyclen.
Herrn Prof. Dr.H. Nowotny gewidment. 相似文献
Herrn Prof. Dr.H. Nowotny gewidment. 相似文献
73.
Lorien J. Parker Louis C. Italiano Craig J. Morton Nancy C. Hancock David B. Ascher Jade B. Aitken Hugh H. Harris Pablo Campomanes Ursula Rothlisberger Anastasia De Luca Mario Lo Bello Wee Han Ang Paul J. Dyson Michael W. Parker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(28):7705-7705
74.
Ursula Schirmeier 《Potential Analysis》1992,1(2):133-140
A classical result of G. Bouligand states that bounded harmonic functions can be extended across closed polar sets. F.-Y. Maeda replaced the boundedness assumption by the condition of energy finiteness for harmonic spaces with Green function.This paper proves this result for generalP-harmonic spaces and shows that the extension property for a harmonic functionu and the condition of energy finiteness are equivalent to a majorization property foru
2
. 相似文献
75.
76.
S?ren Diegelmann Vanessa Nieratschker Ursula Werner Jürgen Hoppe Troy Zars Erich Buchner 《BMC neuroscience》2006,7(1):76
Background
Synapsins are abundant synaptic vesicle associated phosphoproteins that are involved in the fine regulation of neurotransmitter release. The Drosophila member of this protein family contains three conserved domains (A, C, and E) and is expressed in most or all synaptic terminals. Similar to mouse mutants, synapsin knock-out flies show no obvious structural defects but are disturbed in complex behaviour, notably learning and memory. 相似文献77.
Ursula Hamenstädt 《Mathematische Annalen》1995,301(1):677-698
78.
A fewest switches trajectory surface hopping algorithm based on linear response time-dependent density-functional theory is developed and implemented into the plane wave ab initio molecular dynamics package CPMD. A scheme to calculate nonadiabatic couplings using a multi determinantal approximation of the excited state wave function is introduced. The method is applied to the study of the photorelaxation of protonated formaldimine, a minimal model of the rhodopsin chromophore retinal. A good agreement of the structural and dynamic behavior is found with respect to state averaged multiconfiguration self consistent field based trajectory surface hopping. 相似文献
79.
Controlled Light‐Mediated Preparation of Gold Nanoparticles by a Norrish Type I Reaction of Photoactive Polymers 下载免费PDF全文
Florian Mäsing Dr. Artur Mardyukov Carsten Doerenkamp Prof. Dr. Hellmut Eckert Ursula Malkus Harald Nüsse Prof. Dr. Jürgen Klingauf Prof. Dr. Armido Studer 《Angewandte Chemie (International ed. in English)》2015,54(43):12612-12617
Gold nanoparticles (AuNPs) are subjects of broad interest in scientific community due to their promising physicochemical properties. Herein we report the facile and controlled light‐mediated preparation of gold nanoparticles through a Norrish type I reaction of photoactive polymers. These carefully designed polymers act as reagents for the photochemical reduction of gold ions, as well as stabilizers for the in situ generated AuNPs. Manipulating the length and composition of the photoactive polymers allows for control of AuNP size. Nanoparticle diameter can be controlled from 1.5 nm to 9.6 nm. 相似文献
80.
Inside Cover: Local Control Theory in Trajectory Surface Hopping Dynamics Applied to the Excited‐State Proton Transfer of 4‐Hydroxyacridine (ChemPhysChem 10/2015) 下载免费PDF全文