An analysis of generalised heuristics for vehicle routing and personnel rostering problems

The present study investigates the performance of heuristics while solving problems with routing and rostering characteristics. The target problems include scheduling and routing home care, security and maintenance personnel. In analysing the behaviour of the heuristics and determining the requirements for solving the aforementioned problems, the winning hyper-heuristic from the first International Cross-domain Heuristic Search Challenge (CHeSC 2011) is employed. The completely new application of a hyper-heuristic as an analysis tool offers promising perspectives for supporting dedicated heuristic development. The experimental results reveal that different low-level heuristics perform better on different problems and that their performance varies during a search process. The following characteristics affect the performance of the heuristics: the planning horizon, the number of activities and lastly the number of resources. The body of this paper details both these characteristics and also discusses the required features for embedding in an algorithm to solve problems particularly with a vehicle routing component.     

Anodic Voltammetric Determination of an Atypical Antipsychotic Drug Amisulphide in Pharmaceutical Dosage Forms Using Electrochemical fsDNA Biosensor

Russian Journal of Electrochemistry - In this study, a new biosensor for amisulpride (ASP) determination is defined. The interaction between ASP and fish sperm double-stranded DNA (FSdsDNA) was...     

Tandem rearrangements of a cyclic bis-allene

Reaction of the bis-dibromocarbene adduct of cyclonona-1,4,7-triene with methyllithium leads to a mixture of meso and racemic cycloundeca-1,2,5,6,9-pentaenes; the former rearranges at ambient temperature through a set of pericyclic reactions.     

Chiral 2-(2-hydroxyaryl)alcohols (HAROLs) with a 1,4-diol scaffold as a new family of ligands and organocatalysts

Efficient and modular syntheses of chiral 2-(2-hydroxyaryl)alcohols (HAROLs), novel 1,4-diols carrying one phenolic and one alcohol hydroxyl group, have been developed which led to generation of a small library of structurally diverse HAROLs in enantiomerically pure form. Of the different HAROLs examined, a HAROL based on the indan backbone exhibited the highest activity and enantioselectivity in the 1,2-addition of certain organometallic compounds to aldehydes in the presence of Ti(OⁱPr)₄ (up to 97% y, 88% ee) and performed as a hydrogen-bond donor organocatalyst in the Morita-Baylis-Hillman reaction, promoted by trialkylphosphines.     

Similarity of hybrid numbers

The set of hybrid numbers $𝕂$ is a noncommutative number system that unified and generalized the complex, dual, and double (hyperbolic) numbers with the relation ih =− hi =ε+ i. Two hybrid numbers p and q are said to be similar if there exist a nonlightlike hybrid number x satisfying the equality x ⁻¹ qx = p . And, it is denoted by p ∼ q . In this paper, we study the concept of similarity for hybrid numbers by solving the linear equations px = xq and qx − xp = c for $\text{◂,▸}\mathbf{p},\mathbf{q},\mathbf{c}\in 𝕂\mathbf{.}$     

Synthesis of Chiral Calix[4]arene Derivative and Evaluation of its Recognition Properties

The article describes the synthesis and extraction properties of a new chiral calix[4]arene Schiff base ligand 5, which has been synthesized from 5,17-diformyl-25,27-bis-(4-nitrobenzyloxy)-26,28-dihidroxycalix[4]arene (4) by treatment with (S)-(-)-1-phenylethylamine. In this synthesis, it was thought to explore the role of chiral, as well as Schiff base sites in the recognition of targeted species ions (such as dichromate anions) as well as neutral/chiral molecules. At low pH, the ligand 5 is more effective for transferring the dichromate anions from an aqueous into a dichloromethane layer; may be due to the protonation of nitrogen atoms.

The extraction properties of ligand 5 towards the some selected α -amino acid methylesters are also reported. However, the ligand 5 did not display any selectivity towards the selected α-amino acid methylesters.