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1.
Journal of Global Optimization - The capacitated vehicle routing problem (CVRP) is the well-known combinatorial optimization problem having numerous practically important applications. CVRP is...  相似文献   
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The conventional explanation of delayed-choice experiments appears to violate our causal intuition at the quantum level. I reanalyze these experiments using time-reversed and time-symmetric formulations of quantum mechanics. The time-reversed formulation does not give the same experimental predictions. The time-symmetric formulation gives the same experimental predictions but actually violates our causal intuition at the quantum level. I explore the reasons why our causal intuition may be wrong at the quantum level, suggest how conventional causation might be recovered in the classical limit, propose a quantum analog to the classical block universe viewpoint, and speculate on implications of the time-symmetric formulation for cosmological boundary conditions.  相似文献   
4.
Methodology and Computing in Applied Probability - A new nonparametric graphical test of significance of a covariate in functional GLM is proposed. Our approach is especially interesting due to its...  相似文献   
5.
Solutions of boundary value problems in three‐dimensional domains with edges may exhibit singularities which are known to influence both the accuracy of the finite element solutions and the rate of convergence in the error estimates. This paper considers boundary value problems for the Poisson equation on typical domains Ω ? ?3 with edge singularities and presents, on the one hand, explicit computational formulas for the flux intensity functions. On the other hand, it proposes and analyzes a nonconforming finite element method on regular meshes for the efficient treatment of the singularities. The novelty of the present method is the use of the explicit formulas for the flux intensity functions in defining a postprocessing procedure in the finite element approximation of the solution. A priori error estimates in H1(Ω) show that the present algorithm exhibits the same rate of convergence as it is known for problems with regular solutions.  相似文献   
6.
I numerically simulate and compare the entanglement of two quanta using the conventional formulation of quantum mechanics and a time-symmetric formulation that has no collapse postulate. The experimental predictions of the two formulations are identical, but the entanglement predictions are significantly different. The time-symmetric formulation reveals an experimentally testable discrepancy in the original quantum analysis of the Hanbury Brown–Twiss experiment, suggests solutions to some parts of the nonlocality and measurement problems, fixes known time asymmetries in the conventional formulation, and answers Bell’s question “How do you convert an ’and’ into an ’or’?”  相似文献   
7.
Understanding the behaviour of short-chain hydrocarbons confined to porous solids informs the targeted extraction of natural resources from geological features, and underpins rational developments in separation, storage and catalytic conversion processes. Herein, we report the application of low-field (12.7 MHz) 1H nuclear magnetic resonance (NMR) relaxation measurements to characterise ethane dynamics within mesoporous silica materials exhibiting mean pore diameters between 6 and 50 nm. Our measurements provide NMR-based adsorption isotherms within the range 25–50 bar and at ambient temperature, incorporating the ethane condensation point (40.7 bar at our experimental temperature of 23.6 °C). The quantitative nature of the acquired data is validated via a direct comparison of NMR-derived excess adsorption capacities with ex situ gravimetric ethane adsorption measurements, which are demonstrated to agree to within 0.2 mmol g−1 of the observed ethane capacity. NMR relaxation time distributions are further demonstrated as a means to decouple interparticle and mesopore dominated adsorption phenomena, with unexpectedly rapid relaxation rates associated with interparticle ethane gas confirmed via a direct comparison with NMR self-diffusion analysis.  相似文献   
8.
Advances in Data Analysis and Classification - In the original publication of the article, the line after equation (5) has been published incorrectly  相似文献   
9.
The para-selective fluorination reaction of anilides using electrochemically generated hypervalent ArIF2 is reported, with Et3N ⋅ 5HF serving as fluoride source and as supporting electrolyte. This electrochemical reaction is characterized by a simple set-up, easy scalability and affords a broad variety of fluorinated anilides from easily accessible anilides in good yields up to 86 %.  相似文献   
10.
Controlling redox activity of judiciously appended redox units on a photo-sensitive molecular core is an effective strategy for visible light energy harvesting and storage. The first example of a photosensitizer - electron donor coordination compound in which the photoinduced electron transfer step is used for light to electrical energy conversion and storage is reported. A photo-responsive Ru-diimine module conjugated with redox-active catechol groups in [Ru(II)(phenanthroline-5,6-diolate)3]4− photosensitizer can mediate photoinduced catechol to dione oxidation in the presence of a sacrificial electron acceptor or at the surface of an electrode. Under potentiostatic condition, visible light triggered current density enhancement confirmed the light harvesting ability of this photosensitizer. Upon implementation in galvanostatic charge-discharge of a Li battery configuration, the storage capacity was found to be increased by 100 %, under 470 nm illumination with output power of 4.0 mW/cm−2. This proof-of-concept molecular system marks an important milestone towards a new generation of molecular photo-rechargeable materials.  相似文献   
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