Search results for "combinatorial"

Vehicle scheduling for rental-with-driver services

2021

Abstract In this paper, we introduce a new vehicle scheduling problem (VSP) with driver consistency faced by rental-with-driver companies. A weekly time-horizon is considered and a set of potential customers, each one associated with a list of required tasks, is assumed. The company can choose to accept or reject a customer, but if accepted, all required tasks must be performed by the same driver. A profit is associated with each customer. The goal is to maximize the company’s total profit, by respecting a list of daily and the weekly drivers’ workload limitations imposed by drivers’ contracts. We propose a mathematical formulation of the problem and design an exact solution method based on…

Automating the Parameter Selection in VRP: An Off-line Parameter Tuning Tool Comparison

2014

Vehicle route optimization is an important application of combinatorial optimization. Therefore, a variety of methods has been proposed to solve different challenging vehicle routing problems. An important step in adopting these methods to solve real-life problems is to find appropriate parameters for the routing algorithms. In this chapter, we show how this task can be automated using parameter tuning by presenting a set of comparative experiments on seven state-of-the-art tuning methods. We analyze the suitability of these methods in configuring routing algorithms, and give the first critical comparison of automated parameter tuners in vehicle routing. Our experimental results show that t…

Scatter Search and Path-Relinking: Fundamentals, Advances, and Applications

2010

Scatter search is an evolutionary metaheuristic that explores solution spaces by evolving a set of reference points, operating on a small set of solutions while making only limited use of randomization. We give a comprehensive description of the elements and methods that make up its template, including the most recent elements incorporated in successful applications in both global and combinatorial optimization. Path-relinking is an intensification strategy to explore trajectories connecting elite solutions obtained by heuristic methods such as scatter search, tabu search, and GRASP. We describe its mechanics, implementation issues, randomization, the use of pools of high-quality solutions …

Forewords-Special Issue Combinatorial Pattern Matching 2011

2013

Preface

2011

Hydroxamate Titanium–Organic Frameworks and the Effect of Siderophore-Type Linkers over Their Photocatalytic Activity

2019

The chemistry of metal–organic frameworks (MOFs) relies on the controlled linking of organic molecules and inorganic secondary building units to assemble an unlimited number of reticular frameworks. However, the design of porous solids with chemical stability still remains limited to carboxylate or azolate groups. There is a timely opportunity to develop new synthetic platforms that make use of unexplored metal binding groups to produce metal–linker joints with hydrolytic stability. Living organisms use siderophores (iron carriers in Greek) to effectively assimilate iron in soluble form. These compounds make use of hard oxo donors as hydroxamate or catecholate groups to coordinate metal Lew…

Enzyme-responsive intracellular-controlled release using silica mesoporous nanoparticles capped with ε-poly-L-lysine.

2014

The synthesis and characterization of two new capped silica mesoporous nanoparticles for controlled delivery purposes are described. Capped hybrid systems consist of MCM-41 nanoparticles functionalized on the outer surface with polymer epsilon-poly-L-lysine by two different anchoring strategies. In both cases, nanoparticles were loaded with model dye molecule [Ru(bipy)(3)](2+). An anchoring strategy involved the random formation of urea bonds by the treatment of propyl isocyanate-functionalized MCM-41 nanoparticles with the lysine amino groups located on the epsilon-poly-L-lysine backbone (solid Ru-rLys-S1). The second strategy involved a specific attachment through the carboxyl terminus of…

Synthesis and Biological Evaluation of Organometallic Complexes Bearing Bis‐1,8‐naphthalimide Ligands

2018

Organometallic N-heterocyclic carbene (NHC) complexes with intercalating bis-naphthalimide ligands were prepared and evaluated biologically. Cytotoxic effects against tumor cells or bacteria were strongly ligand dependent with minor influence of the metal (Ag, Ru, Rh, Au) centers. Complex 8b with a rhodium(I) NHC moiety was studied in more detail for its DNA interacting properties in comparison to the metal free ligand. These studies showed a good DNA binding pattern with some preference for the telomeric quadruplex structure hTelo. Complex 8b was also shown to trigger additional coordinative binding to the DNA and therefore represents an useful tool compound with a mixed intercalative/coor…

Cooperative Catechol-Functionalized Polypept(o)ide Brushes and Ag Nanoparticles for Combination of Protein Resistance and Antimicrobial Activity on M…

2018

Prevention of biofouling and microbial contamination of implanted biomedical devices is essential to maintain their functionality and biocompatibility. For this purpose, polypept(o)ide block copolymers have been developed, in which a protein-resistant polysarcosine (pSar) block is combined with a dopamine-modified poly(glutamic acid) block for surface coating and silver nanoparticles (Ag NPs) formation. In the development of a novel, versatile, and biocompatible antibacterial surface coating, block lengths pSar were varied to derive structure-property relationships. Notably, the catechol moiety performs two important tasks in parallel; primarily it acts as an efficient anchoring group to me…

Selective Synthesis of Partially Protected Nonsymmetric Biphenols by Reagent‐ and Metal‐Free Anodic Cross‐Coupling Reaction

2016

The oxidative cross-coupling of aromatic substrates without the necessity of leaving groups or catalysts is described. The selective formation of partially protected nonsymmetric 2,2'-biphenols via electroorganic synthesis was accomplished with a high yield of isolated product. Since electric current is employed as the terminal oxidant, the reaction is reagent-free; no reagent waste is generated as only electrons are involved. The reaction is conducted in an undivided cell, and is suitable for scale-up and inherently safe. The implementation of O-silyl-protected phenols in this transformation results in both significantly enhanced yields and higher selectivity for the desired nonsymmetric 2…