43 research outputs found
Bundle pricing of inventories with stochastic demand
Cataloged from PDF version of article.We consider a retailer selling a fixed inventory of two perishable products over a finite horizon. Assuming Poisson arrivals and a
bivariate reservation price distribution, we determine the optimal product and bundle prices that maximize the expected revenue. Our
results indicate that the performances of mixed bundling, pure bundling and unbundled sales strategies heavily depend on the parameters
of the demand process and the initial inventory levels. Bundling appears to be most effective with negatively correlated reservation prices
and high starting inventory levels. When the starting inventory levels are equal and in excess of average demand, most of the benefits of
bundling can be achieved through pure bundling. However, the mixed bundling strategy dominates the other two when the starting
inventory levels are not equal. We also observe that an incorrect modeling of the reservation prices may lead to significant losses.
The model is extended to allow for price changes during the selling horizon. It is shown that offering price bundles mid-season may
be more effective than changing individual product prices.
2008 Elsevier B.V. All rights reserved
Convection-reaction equation based magnetic resonance electrical properties tomography (cr-MREPT)
Cataloged from PDF version of article.Images of electrical conductivity and permittivity
of tissues may be used for diagnostic purposes as well as for
estimating local specific absorption rate distributions. Magnetic
resonance electrical properties tomography (MREPT) aims at
noninvasively obtaining conductivity and permittivity images
at radio-frequency frequencies of magnetic resonance imaging
systems. MREPT algorithms are based on measuring the B1 field
which is perturbed by the electrical properties of the imaged
object. In this study, the relation between the electrical properties
and the measured B1 field is formulated for the first time as a
well-known convection-reaction equation. The suggested novel
algorithm, called “cr-MREPT,” is based on the solution of this
equation on a triangular mesh, and in contrast to previously
proposed algorithms, it is applicable in practice not only for
regions where electrical properties are relatively constant but also
for regions where they vary. The convective field of the convection-reaction
equation depends on the spatial derivatives of the
B1 field, and in the regions where its magnitude is low, a spot-like
artifact is observed in the reconstructed electrical properties
images. For eliminating this artifact, two different methods are
developed, namely “constrained cr-MREPT” and “double-excitation
cr-MREPT.” Successful reconstructions are obtained using
noisy and noise-free simulated data, and experimental data from
phantoms
Serotype distribution and antibiotic resistance among isolates of streptococcus pneumoniae causing invasive pneumococcal disease in adults in Turkey: 2005-2015
WOS: 000374876700187
Cancellous bone grafting in alveolar cleft repair: New experience
WOS: 000177936600012PubMed ID: 12218794Bone grafting plays an important role in the dental rehabilitation of patients with alveolar cleft. During the period between 1993 and 2001, 12 patients with alveolar clefts have been treated in our clinic. Cancellous iliac bone grafts were used in all 12 patients. Seven patients had left and five patients had right complete unilateral cleft lip and complete cleft palate operations. All patients had palatal fistulas. The ages were between 4 and 18 years (mean age, 10.5 y). Seven of them were female (58.4%) and 5 were male (41.6%). All the cancellous grafts survived. Enough filling and the closure of the fistulas were achieved except one patient who had wound dehiscence and partial graft loss. The patients experienced a limp for 2 days (mean time) because of the donor site. This surgical procedure achieves successful results if it is used with the proper indication in suitable cases