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531.
Alessio Ishizaka Ashraf Labib 《The Journal of the Operational Research Society》2014,65(10):1475-1489
Disasters are, by their nature, very complex phenomena. Their modelling using a systematic and logical methodology can help us identify their root causes and may facilitate in allocating appropriate resources to prevent such situations. Although techniques exist to model such phenomena, a single off-the-shelf model is insufficient to provide an effective and realistic analysis to prevent disasters due to its inherent assumptions. In order to overcome these limitations of single methods, this article proposes a hybrid model of four methods to optimise a safety investment. First, a hierarchy is constructed with a problem structuring approach. Second, a new graphical representation, the Crisis Tree Analysis, is introduced to visualise how a combination of basic events may lead to a disaster. Third, the criticality of each event is assessed using the Analytic Hierarchy Process. Finally, a mathematical programming model is proposed to calculate the optimal allocation of available funds in order to avoid the disaster. A case study of the Bhopal disaster is used to illustrate the proposed four-step method. 相似文献
532.
Determination of f(s)/f(d) for 7 TeV pp collisions and measurement of the B0→D-K+ branching fraction
Aaij R Adeva B Adinolfi M Adrover C Affolder A Ajaltouni Z Albrecht J Alessio F Alexander M Alkhazov G Alvarez Cartelle P Alves AA Amato S Amhis Y Amoraal J Anderson J Appleby RB Gutierrez OA Arrabito L Artamonov A Artuso M Aslanides E Auriemma G Bachmann S Back JJ Bailey DS Balagura V Baldini W Barlow RJ Barschel C Barsuk S Barter W Bates A Bauer C Bauer T Bay A Bediaga I Belous K Belyaev I Ben-Haim E Benayoun M Bencivenni G Benson S Benton J Bernet R Bettler MO van Beuzekom M Bien A Bifani S 《Physical review letters》2011,107(21):211801
The relative abundance of the three decay modes B(0)→D(-)K(+), B(0)→D(-)π(+), and B(s)(0)→D(s)(-)π(+) produced in 7 TeV pp collisions at the LHC is determined from data corresponding to an integrated luminosity of 35 pb(-1). The branching fraction of B(0)→D(-)K(+) is found to be B(B(0)→D(-)K(+)) = (2.01 ± 0.18(stat) ± 0.14(syst)) × 10(-4). The ratio of fragmentation fractions f(s)/f(d) is determined through the relative abundance of B(s)(0)→D(s)(-)π(+) to B(0)→D(-)K(+) and B(0)→D(-)π(+), leading to f(s)/f(d) = 0.253 ± 0.017 ± 0.017 ± 0.020, where the uncertainties are statistical, systematic, and theoretical, respectively. 相似文献
533.
Given two quantum memories for continuous variables and the possibility to perform passive optical operations on the optical modes before or after the storage, two possible scenarios arise resulting in generally different degrees of final entanglement. Namely, one could either store an entangled state and retrieve it directly from the memory, or rather store two separate single-mode squeezed states and then combine them with a beam-splitter to generate the final entangled state. In this Letter, we analytically determine which of the two options yields more entanglement for several regions of the system?s parameters, and quantify the advantage it entails. 相似文献
534.
We are interested in the existence of infinitely many positive non-radial solutions of a Schrödinger–Poisson system with a positive radial bounded external potential decaying at infinity. 相似文献
535.
536.
Francesco Petitta Augusto C. Ponce Alessio Porretta 《Journal of Evolution Equations》2011,11(4):861-905
Given a parabolic cylinder Q = (0, T) × Ω, where
W ì \mathbb RN{\Omega\subset \mathbb {R}^N} is a bounded domain, we prove new properties of solutions of
ut-Dp u = m \textin Qu_t-\Delta_p u = \mu \quad \text{in }Q 相似文献
537.
Curti C Battistini L Sartori A Lodola A Mor M Rassu G Pelosi G Zanardi F Casiraghi G 《Organic letters》2011,13(17):4738-4741
Virtually perfect transmittal of the enolate reactivity up to five conjugated double bonds from the origin allows a series of furan-based silyloxypolyenes to add to aldehyde carbonyls at the most distant point of the molecule. Denmark's axially chiral bisphosphoramide/SiCl(4) combination catalyzes these scantly precedented, long-range Mukaiyama-type vinylogous aldol reactions efficiently, providing a palette of extended γ-alkylidene butenolide carbinols with complete ω-site selectivity and good to excellent levels of enantioselectivity. 相似文献
538.
We study the existence of solutions u:R3→R2 for the semilinear elliptic systems
equation(0.1) −Δu(x,y,z)+∇W(u(x,y,z))=0, 539.
Marie Dupraz Simonetta Filippi Alessio Gizzi Alfio Quarteroni Ricardo Ruiz‐Baier 《Mathematical Methods in the Applied Sciences》2015,38(6):1046-1058
In this paper, we are interested in the spatio‐temporal dynamics of the transmembrane potential in paced isotropic and anisotropic cardiac tissues. In particular, we observe a specific precursor of cardiac arrhythmias that is the presence of alternans in the action potential duration. The underlying mathematical model consists of a reaction–diffusion system describing the propagation of the electric potential and the nonlinear interaction with ionic gating variables. Either conforming piecewise continuous finite elements or a finite volume‐element scheme are employed for the spatial discretization of all fields, whereas operator splitting strategies of first and second order are used for the time integration. We also describe an efficient mechanism to compute pseudo‐ECG signals, and we analyze restitution curves and alternans patterns for physiological and pathological cardiac rhythms. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
540.
Analysis of genomic methylation level using micellar electrokinetic chromatography with UV detection
Alessio Ferrone Mirko Pesce Sara Franceschelli Lorenza Speranza Maria Anna De Lutiis Alfredo Grilli Mario Felaco Antonia Patruno 《Electrophoresis》2013,34(15):2275-2280
Analytical methods for quantification of 5′‐methylcytosine in genomes are important tools to investigate epigenetic changes in gene expression during development, differentiation, aging, or cancer. Here, we report a novel genomic methylation content assay based on enzymatic hydrolysis of DNA and MEKC separation of 5′‐deoxyribonucleoside monophosphates (dNMP) using the cationic surfactant CTAB as pseudostationary phase. Calf Thymus DNA was used during method development to determine electrophoretic parameters and electrolyte composition for a complete separation between 2′‐deoxycytosine‐5′‐monophosphate and 2′‐deoxy‐5′‐methylcytosine 5′‐monophosphate (d5mCMP). Methylated and not methylated oligonucleotides were used to confirm the identity of each peak and evaluate analytical parameters of the method. The LOD of the method was found to be 12.5 pmol/μL for d5mCMP. 相似文献
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