2,736 research outputs found
The Role of Discount Vouchers in Market with Customer Valuation Uncertainty
Online discount voucher market In the discount voucher market, customers usually face two types of valuation uncertainty, namely, preference uncertainty and consumption state uncertainty. Preference uncertainty is related to the customer\u27s lack of relevant experience with the merchant, whereas consumption state uncertainty is related to the advance selling nature of the discount voucher mechanism. By taking a comprehensive perspective (i.e., considering revenue management and promotion effect at the same time), we find (i) no show of voucher buyers may not be a good thing for the merchant, especially for those large or start-up ones; (ii) offering refund may always hurt the merchant\u27s profit and the PayPal model may not be optimal in terms of maximizing social welfare; and (iii) market segmentation is not necessary for the profitability of promotion
Contouring Accuracy Improvement Using an Adaptive Feedrate Planning Method for CNC Machine Tools
AbstractThe reduction of contour error plays an important role in achieving high accuracy machining. To reduce contour error, most of previous studies have focused on developing advanced control strategies. As an alternative strategy, contouring accuracy improvement using an adaptive feedrate planning method is proposed in this paper. First, a typical PID controller is adopted to build the contour error model, from which the feedrate can be scheduled in the contour error violated zones. Then, the relations between each constraint and the cutter tip feedrate are derived. After that, a linear programming model is applied to obtain the optimal feedrate profile on the sampling positions of the given tool path. Finally, illustrated examples are given to validate the feasibility and applicability of the proposed feedrate planning method. The comparison results show that the proposed method has a significant effect on improving contouring accuracy
Global analysis of uncapped mRNA changes under drought stress and microRNA-dependent endonucleolytic cleavages in foxtail millet
GO functional enrichment analysis for different decay pattern mRNA. Gene Ontology (GO) analysis was performed for the type I, II, IV genes using WEGO which organizes information for cellular component categories, molecular function and biological process. The Pearson Chi-square test was used for statistical analysis. GO categories that show a significant (Îą =0.05) enrichment were analyzed and displayed here. (PDF 396Â kb
Proton mass decomposition
We report the results on the proton mass decomposition and also on the
related quark and glue momentum fractions. The results are based on overlap
valence fermions on four ensembles of DWF configurations with three
lattice spacings and volumes, and several pion masses including the physical
pion mass. With 1-loop perturbative calculation and proper normalization of the
glue operator, we find that the and quark masses contribute 9(2)\%
to the proton mass. The quark energy and glue field energy contribute 31(5)\%
and 37(5)\% respectively in the scheme at GeV. The
trace anomaly gives the remaining 23(1)\% contribution. The and glue
momentum fractions in the scheme are consistent with the global
analysis at GeV.Comment: 6 pages. Proceedings of the 35th International Symposium on Lattice
Field Theory (Lattice2017), Granada, Spai
Applications of Fiber Reinforced Polymer Composites
2015-2016 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Dimensional crossover of thermal conductance in graphene nanoribbons: A first-principles approach
First-principles density-functional calculations are performed to investigate
the thermal transport properties in graphene nanoribbons (GNRs). The
dimensional crossover of thermal conductance from one to two dimensions (2D) is
clearly demonstrated with increasing ribbon width. The thermal conductance of
GNRs in a few nanometer width already exhibits an approximate low-temperature
dependence of , like that of 2D graphene sheet which is attributed to
the quadratic nature of dispersion relation for the out-of-plane acoustic
phonon modes. Using a zone-folding method, we heuristically derive the
dimensional crossover of thermal conductance with the increase of ribbon width.
Combining our calculations with the experimental phonon mean-free path, some
typical values of thermal conductivity at room temperature are estimated for
GNRs and for 2D graphene sheet, respectively. Our findings clarify the issue of
low-temperature dependence of thermal transport in GNRs and suggest a
calibration range of thermal conductivity for experimental measurements in
graphene-based materials.Comment: 18 pages, 4 figure
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