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41.
Exact and heuristic methodologies for scheduling in hospitals: problems, formulations and algorithms
Jeroen Beliën 《4OR: A Quarterly Journal of Operations Research》2007,5(2):157-160
This text summarizes the PhD thesis defended by the author in January 2006 under the supervision of Professor Erik Demeulemeester
at the Katholieke Universiteit Leuven. The thesis is written in English and is available from the author’s website (http://www.econ.kuleuven.be/jeroen.belien).
In this research we propose a number of exact and heuristic algorithms for various scheduling problems encountered in hospitals.
The emphasis lies on the design of new methodologies as well as on the applicability of the algorithms in real-life environments.
The main contributions include a new decomposition approach for a particular class of staff scheduling problems, an extensive
study of master surgery scheduling algorithms that aim at leveling the resultant bed occupancy and an innovative method for
integrating nurse and surgery scheduling.
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We have calculated cross sections and rate coefficients for low-energy electron impact excitation of the nitrogen molecule from vibrationally excited levels N2(v) 1-8. Calculations are performed in the 2Pig shape resonance energy region, from 0 to 5 eV. The cross sections are determined by using our recent integral cross section measurements of the ground level vibrational excitation and the most recent cross sections for elastic electron scattering, applying the principle of detailed balance. The rate coefficient calculations are performed for the Maxwellian electron energy distribution. By using extended Monte Carlo simulations, the electron energy distribution functions (EEDF) and the rate coefficients are also determined for the nonequilibrium conditions, in the presence of the homogeneous external electric field for the typical, moderate values of the electric field over gas number density ratios, E/N. 相似文献
45.
Sébastien G. Guillet Dr. Ishfaq Ibni Hashim Marek Beliš Prof. Dr. Kristof Van Hecke Prof. Dr. Catherine S. J. Cazin Prof. Dr. Steven. P. Nolan 《欧洲无机化学杂志》2023,26(24):e202300327
A simple synthetic method to access a wide range of [Rh(acac)(CO)(NHC)] complexes is described. In situ infra-red monitoring provides insights into the mechanism of the reaction, including the identification of a key intermediate. An understanding of the reaction mechanism leads to the discovery of novel pathways to commonly used congeners. 相似文献
46.
Markusson H Belières JP Johansson P Angell CA Jacobsson P 《The journal of physical chemistry. A》2007,111(35):8717-8723
We have systematically investigated combinations of anions and cations in a number of protic ionic liquids based on alkylamines and used ab initio methods to gain insight into the parameters determining their liquid range and their conductivity. A simple, almost linear, relation of the experimentally determined melting temperature with the calculated volume of the anion forming the ionic liquid is found, whereas the dependence of the melting temperature with increasing cation volume goes through a minimum for relatively short side chain length. On the basis of the present results, we propose a strategy to predict the nature of protic ionic liquids in terms of low vapor pressure and conductivity. Comparisons with previously reported strategies for prediction of melting temperatures for aprotic ionic liquids are also made. 相似文献
47.
Topological edge solitons represent a significant research topic in the nonlinear topological photonics. They maintain their profiles during propagation, due to the joint action of lattice potential and nonlinearity, and at the same time are immune to defects or disorders, thanks to the topological protection. In the past few years topological edge solitons were reported in systems composed of helical waveguide arrays, in which the time-reversal symmetry is effectively broken. Very recently, topological valley Hall edge solitons have been demonstrated in straight waveguide arrays with the time-reversal symmetry preserved. However, these were scalar solitary structures. Here, for the first time, we report vector valley Hall edge solitons in straight waveguide arrays arranged according to the photonic lattice with innate type-II Dirac cones, which is different from the traditional photonic lattices with type-I Dirac cones such as honeycomb lattice. This comes about because the valley Hall edge state can possess both negative and positive dispersions, which allows the mixing of two different edge states into a vector soliton. Our results not only provide a novel avenue for manipulating topological edge states in the nonlinear regime, but also enlighten relevant research based on the lattices with type-II Dirac cones. 相似文献
48.
Andreja Gajovi Jelena Vukajlovi Pletina Kristina
agar Milivoj Plodinec Sao turm Miran eh 《Journal of Raman spectroscopy : JRS》2013,44(3):412-420
In the present work, multiphase polycrystalline BTO nanorods were synthesized using template‐assisted sol–gel deposition and their structural evolution was studied using thermo Raman spectroscopy, X‐ray diffractometry and high‐resolution transmission electron microscopy (HRTEM). In the BTO nanorods, the tetragonal phase was the dominant one, while both Raman and HRTEM indicated a coexistence with the high‐temperature hexagonal polymorph. This phase was stable across the whole of the investigated temperature range (from −95 °C to 200 °C). The investigated nanorods underwent a diffuse phase transition from tetragonal to cubic with respect to the temperature, whereas the final phase‐transition temperature was shifted to higher values compared to that expected for BTO. The low‐temperature orthorhombic‐to‐rhombohedral phase transition was also shifted to higher temperatures. These differences could be explained by the strain induced by the presence of hexagonal nanolamellas intergrown within the tetragonal nanocrystals. This result indicates that the temperature of the ferroelectric phase transition in polycrystalline BTO nanorods can be manipulated by introducing a stable hexagonal phase. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
49.
Slobodan M. Vuković Najdan B. Aleksić Dejan V. Timotijević Milivoj R. Belic 《Optics Communications》2012,285(6):1148-1154
We studied electromagnetic wave transmission through layered structures that include negative index materials. The excitation of leaky guided modes leads to the formation of anomalous lateral shifts in the reflected beam with a double-peak structure and in the transmitted beam with a single-peak structure. In the absence of losses, we demonstrate that the total transparency (i.e. zero reflection) of the slab waveguide with the negative index material can be achieved under conditions in which high reflectivity is normally expected. We demonstrate the trade-off effect between the high transmission and the high lateral shift. This peculiar effect exists not only for the pure TE or the pure TM polarization of the obliquely incident radiation, but also under certain circumstances for both of them simultaneously i.e. for the nonpolarized radiation. 相似文献
50.
Dragana Jović Milivoj R. Belić Yuri S. Kivshar Cornelia Denz 《Optics Communications》2012,285(3):352-355
We investigated the influence of edges and corners on the Anderson localization of light in disordered two-dimensional photonic lattices that are optically induced in nonlinear saturable photorefractive media. A systematic quantitative study of gradual transition from corner to bulk Anderson localization in truncated two-dimensional photonic lattices was carried out. We analyzed numerically the localization at several corners and edges of the square and triangular photonic lattices and compared them with the localization in bulk medium. We found that, for strong disorder, corners and edges effectively suppress Anderson localization, as compared to the bulk, but to a varying degree. 相似文献