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41.
42.
Heuristic algorithms for a vehicle routing problem with simultaneous delivery and pickup and time windows in home health care 总被引:1,自引:0,他引:1
This paper addresses a vehicle scheduling problem encountered in home health care logistics. It concerns the delivery of drugs and medical devices from the home care company’s pharmacy to patients’ homes, delivery of special drugs from a hospital to patients, pickup of bio samples and unused drugs and medical devices from patients. The problem can be considered as a special vehicle routing problem with simultaneous delivery and pickup and time windows, with four types of demands: delivery from depot to patient, delivery from a hospital to patient, pickup from a patient to depot and pickup from a patient to a medical lab. Each patient is visited by one vehicle and each vehicle visits each node at most once. Patients are associated with time windows and vehicles with capacity. Two mixed-integer programming models are proposed. We then propose a Genetic Algorithm (GA) and a Tabu Search (TS) method. The GA is based on a permutation chromosome, a split procedure and local search. The TS is based on route assignment attributes of patients, an augmented cost function, route re-optimization, and attribute-based aspiration levels. These approaches are tested on test instances derived from existing VRPTW benchmarks. 相似文献
43.
Phase shifting photoelasticity in white light 总被引:1,自引:0,他引:1
Augusto Ajovalasit Giovanni Petrucci Michele Scafidi 《Optics and Lasers in Engineering》2007,45(5):596
The availability of image acquisition systems has led to the development of digital photoelasticity both in monochromatic and white light. In particular white light has been used mainly with the following methods: Spectral Content Analysis, RGB photoelasticity and phase shifting photoelasticity. Phase shifting photoelasticity in the colour domain has been used effectively for the determination of the isoclinic parameter in order to reduce the influence of the isochromatic fringes. The method has been also proposed for the determination of the isochromatic fringe order. This paper concerns the general characteristics of phase shifting photoelasticity in the colour domain. Special attention is drawn towards the influence of spectral content of the light source, the spectral response of the colour camera filters, the dispersion of the birefringence and the error of quarter wave plates. 相似文献
44.
Xilin Peng Augusto Morrone Konstantin Nikolaev Mark Kief Mark Ostrowski 《Journal of magnetism and magnetic materials》2009,321(18):2902-2910
In this paper, we investigated the effect of background base pressure, wafer-transferring time between process modules, and stack layer material selection on the current-in-plane giant magneto-resistive (CIP-GMR) interface properties and the resulted CIP-GMR performance. Experimental results showed that seed layer/AFM interface, AFM/pinned layer (PL) interface, pinned layer/Ru interface, and reference layer (RL)/Cu spacer interface are among the most critical ones for a CIP-GMR device. By reducing the background impurity level (water moisture and oxygen), optimizing the wafer process flow sequence, and careful stack-layer material selection, such critical interfaces in a CIP-GMR device can be preserved. Consequently, a much robust GMR performance control can be achieved. 相似文献
45.
Dr. Flávio Figueira Igor Marques Dr. Andreia S. F. Farinha Prof. Dr. Augusto C. Tomé Prof. Dr. José A. S. Cavaleiro Prof. Dr. Artur M. S. Silva Prof. Dr. Jonathan Sessler Prof. Dr. Vítor Félix Prof. Dr. João P. C. Tomé 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14349-14355
A novel sapphyrin derivative was obtained from the reaction between a free‐base sapphyrin and dimethyl acetylenedicarboxylate (DMAD). The formation of the new compound involved a double aza‐Michael addition of two pyrrolic NH groups to a DMAD molecule, with the formation of a disubstituted ethano bridge. The NMR spectral data reveal a product with an unsymmetrical structure; DFT calculations provided support for a structure in which the ethano bridge links two adjacent pyrrole units. The present study provides a seemingly unprecedented example of an N,N′‐dinucleophile reacting with DMAD to form a heterocyclic compound in which the two N‐atoms are linked to the two sp3 carbon atoms derived from a substituted acetylene. 相似文献
46.
I. T. L. Bresolin M. Borsoi-Ribeiro W. M. S. C. Tamashiro E. F. P. Augusto M. A. Vijayalakshmi S. M. A. Bueno 《Applied biochemistry and biotechnology》2010,160(7):2148-2165
Monoclonal antibodies (MAbs) have been used for therapies and some analytical procedures as highly purified molecules. Many
techniques have been applied and studied, focusing on monoclonal antibodies purification. In this study, an immobilized metal
affinity chromatography membrane was developed and evaluated for the purification of anti-TNP IgG1 mouse MAbs from cell culture supernatant after precipitation with a 50% saturated ammonium sulfate solution. The chelating
ligands iminodiacetic acid, carboxymethylated aspartic acid (CM-Asp), nitrilotriacetic acid, and tris (carboxymethyl) ethylenediamine
in agarose gels with immobilized Ni(II) and Zn(II) ions were compared for the adsorption and desorption of MAbs. The most
promising chelating ligand—CM-Asp—was then coupled to poly(ethylene vinyl alcohol) (PEVA) hollow fiber membranes. According
to SDS-PAGE and ELISA analyses, a higher selectivity and a purification factor of 85.9 (fraction eluted at 500 mM Tris) were
obtained for IgG1 using PEVA-CM-Asp-Zn(II). The anti-TNP MAb could be eluted under mild pH conditions causing no loss of antigen binding capacity. 相似文献
47.
Barbara Visintin 《Israel Journal of Mathematics》1999,112(1):1-27
A family of the spherical fractional integrals
on the unit sphere Σ
n
in ℝ
n+1 is investigated. This family includes the spherical Radon transform (α = 0) and the Blaschke-Levy representation (α>1). Explicit inversion formulas and a characterization ofT
αƒ are obtained for ƒ belonging to the spacesC
∞,C, Lp and for the case when ƒ is replaced by a finite Borel measure. All admissiblen ≥ 2,α ε ℂ, andp are considered. As a tool we use spherical wavelet transforms associated withT
α. Wavelet type representations are obtained forT
α ƒ, ƒ εL
p, in the case Reα ≤ 0, provided thatT
α is a linear bounded operator inL
p.
Partially supported by the Edmund Landau Center for Research in Mathematical Analysis, sponsored by the Minerva Foundation
(Germany). 相似文献
48.
Louis?Dupaigne Augusto?C.?Ponceaugponce@math.rutgers.edu" title="ponce@ann.jussieu.fr augponce@math.rutgers.edu" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author 《Selecta Mathematica, New Series》2004,10(3):341-358
We present several extensions of the Brezis–Lions Lemma on removable singularities. We also give a positive answer to a question raised by H. Brezis and M. Marcus about an inverse maximum principle for the Laplacian. 相似文献
49.
We extend the classical version of Kato's inequality in order to allow functions u∈L1loc such that Δu is a Radon measure. This inequality has been recently applied by Brezis, Marcus, and Ponce to study the existence of solutions of the nonlinear equation ?Δu+g(u)=μ, where μ is a measure and is a nondecreasing continuous function. To cite this article: H. Brezis, A.C. Ponce, C. R. Acad. Sci. Paris, Ser. I 338 (2004). 相似文献
50.
We demonstrate edge-enhanced imaging produced by volume phase gratings recorded on a polyvinyl alcohol/acrylamide photopolymer. Bragg diffraction, exhibited by volume gratings, modifies the impulse response of the imaging system, facilitating spatial filtering operations with no need for a physical Fourier plane. We demonstrate that Kogelnik's coupled-wave theory can be used to calculate the transfer function for the transmitted and the diffracted orders. The experimental and simulated results agree, and they demonstrate the feasibility of our proposal. 相似文献