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31.
Nathaniel D. Bastian Paul M. Griffin Eric Spero Lawrence V. Fulton 《Optimization Letters》2016,10(5):921-953
Given that it is not always feasible to reach an affected area via land or sea within the first week following a natural disaster, aerial delivery provides the primary means to rapidly supply the affected population. Further, it is often the case that high density delivery of humanitarian aid supplies are taken over by non-friendly groups within the affected population. By using direct airdrop systems to deliver large quantities of individually wrapped food and water items, dispersion among the affected disaster relief population will occur more quickly. In this paper, we proffer a multiple criteria decision analysis (MCDA) framework to optimize the military humanitarian assistance/disaster relief (HA/DR) aerial delivery supply chain network. The model uses stochastic, mixed-integer, weighted goal programming to optimize network design, logistics costs, staging locations, procurement amounts, and inventory levels. The MCDA framework enables decision-makers to explore the trade-offs between military HA/DR aerial delivery supply chain efficiency and responsiveness, while optimizing across a wide range of real-world, probabilistic scenarios to account for the inherent uncertainty in the location of global humanitarian disasters as well as the amount of demand to be met. 相似文献
32.
The photochemistry of simple, alicyclic enones has been the subject of extensive study during the last decade, and this area is the subject of a recent review.2 Investigation of the crossed-cycloaddition of cyclopentenone to a variety of alkenes was undertaken in our laboratory in connection with a program of synthesis of precursors for nonbenzenoid, aromatic systems. In a previous report3 we described the photoaddition of cyclopentenone to cycloheptene, from which four products were identified. 相似文献
33.
This paper concerns the generation of support vector machine classifiers for solving the pattern recognition problem in machine
learning. A method is proposed based on interior-point methods for convex quadratic programming. This interior-point method
uses a linear preconditioned conjugate gradient method with a novel preconditioner to compute each iteration from the previous.
An implementation is developed by adapting the object-oriented package OOQP to the problem structure. Numerical results are
provided, and computational experience is discussed. 相似文献
34.
Griffin JL Nicholls AW Keun HC Mortishire-Smith RJ Nicholson JK Kuehn T 《The Analyst》2002,127(5):582-584
The application of a 1 mm TXI (1H/13C/15N) microlitre NMR probe with z-gradient for metabolic profiling of biofluids is described. The probe was used to provide spectral profiles for rat blood plasma using only approximately 2 microl of fluid with a range of solvent suppression techniques. Using a similar amount of fluid, spectra were obtained from rat and mouse cerebrospinal fluid, demonstrating that the probe could be used to profile rodents metabolically via biofluids previously inaccessible to NMR analysis without the need for termination. 相似文献
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Astrof NS Griffin RG 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,158(1-2):157-163
The process of obtaining sequential resonance assignments for heterogeneous polypeptides and large proteins by solid-state NMR (ssNMR) is impeded by extensive spectral degeneracy in these systems. Even in these challenging cases, the cross peaks are not distributed uniformly over the entire spectral width. Instead, there exist both well-resolved single resonances and distinct groups of resonances well separated from the most crowded region of the spectrum. Here, we present a series of new triple resonance experiments that exploit the non-uniform clustering of resonances in heteronuclear correlation spectra to obtain additional resolution in the more crowded regions of a spectrum. Homonuclear and heteronuclear dipolar recoupling sequences are arranged to achieve directional transfer of coherence between neighboring residues in the peptide sequence. A frequency-selective (soft) pulse is applied to select initial polarization from a limited (and potentially) well-resolved region of the spectrum. The pre-existing resolution of one or more spins is thus utilized to obtain additional resolution in the more crowded regions of the spectrum. A new protocol to utilize these experiments for sequential resonance assignments in peptides and proteins is also demonstrated. 相似文献
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