Experiments and an Improved Method for Solving the Discrete Alternative Multiple-criteria Problem

A number of interactive methods that use convex cones for solving the discrete alternative multiplecriteria problem have appeared in the literature. Convex cones are used to identify inferior alternatives based on the previous responses of the decision-maker. The aim is to identify as many inferior alternatives as possible using the cones so that the decision-maker will be required to make as few pairwise comparisons as possible.In this study we make experiments to see the effects of a number of cone generators, the selection procedure of cone generators, and the order in which pairwise comparisons are made, on the total number of pairwise comparisons. We also develop an algorithm based on the results of the experiments. Our computational experience shows that the algorithm performs well compared with algorithms that require similar information input from the decision-maker.     

Competing magnetic phases on a kagomé staircase

We present thermodynamic and neutron data on Ni3V2O8, a spin-1 system on a kagomé staircase. The extreme degeneracy of the kagomé antiferromagnet is lifted to produce two incommensurate phases at finite T--one amplitude modulated, the other helical--plus a commensurate canted antiferromagnet for T-->0. The H-T phase diagram is described by a model of competing first and second neighbor interactions with smaller anisotropic terms. Ni3V2O8 thus provides an elegant example of order from subleading interactions in a highly frustrated system.     

Solvent‐Catalyzed Ring–Chain–Ring Tautomerization in Axially Chiral Compounds

The mechanism of ring–chain–ring tautomerization and the prominent effect of the solvent environment have been computationally investigated in an effort to explain the enantiomeric interconversion observed in 2‐oxazolidinone derivatives, heterocyclic analogues of biphenyl atropisomers, which were isolated as single stable enantiomers and have the potential to be used as axially chiral catalysts. This study has shed light on the identity of the intermediate species involved in the ring–chain–ring tautomerization process as well as the catalytic effect of polar protic solvents. These mechanistic details will prove very useful in predicting and understanding ring–chain tautomeric equilibria in similar heterocyclic systems and will further enable experimentalists to devise appropriate experimental conditions in which axially chiral catalysts remain stable as single enantiomers.     

An Online Expectation–Maximization Algorithm for Changepoint Models

Changepoint models are widely used to model the heterogeneity of sequential data. We present a novel sequential Monte Carlo (SMC) online expectation–maximization (EM) algorithm for estimating the static parameters of such models. The SMC online EM algorithm has a cost per time which is linear in the number of particles and could be particularly important when the data is representable as a long sequence of observations, since it drastically reduces the computational requirements for implementation. We present an asymptotic analysis for the stability of the SMC estimates used in the online EM algorithm and demonstrate the performance of this scheme by using both simulated and real data originating from DNA analysis. The supplementary materials for the article are available online.     

On the influence of boundary conditions on the modal properties of a base frame

Supports of turbomachineries can be designed as base frames, which are constructions of steel-plates. One of the most important design requirements of the turbomachinery system is to avoid of natural frequencies in the operating speed range. Thus, a rotor dynamics analysis (see e.g. [1]), which is usually carried out using transfer matrix methods or finite element methods has to take the dynamic stiffness of the base frame into account. However, there are several problems to identify this complex and frequency dependent parameter, for example the localization of excitation or measurement responses and the difficulty of the support of base frames, e.g jack screws. In this article the support of a test base frames is analyzed by modal analysis experimentally. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis of a new colorimetric receptor based on calix[4]pyrrole binding oxime for selective recognition of fluoride ions

A colorimetric anion sensor α-meso-heptaethylcalix[4]pyrrole-meso-3-aminophenyl-p-nitrobenzaldoxime was synthesised and characterised by various spectroscopic techniques. Anion-binding studies were carried out using UV–vis, and ¹H NMR titrations, revealing that the receptor exhibits selective recognition towards F^?  over other anions. The selectivity for F^?  among the halides is attributed mainly to the hydrogen bond interaction of the receptor with F^? . Receptor showed colour change from colourless to yellow in the presence of tetrabutylammonium fluoride with 1:2 stoichiometry. Cyclic voltammetry studies, carried out in CH₃CN, provided evidence of an anion-dependent electrochemical response with F^?  ion. This response was particularly dramatic in the case of receptor after the addition of ～1 equiv. of F^?  ion.     

Analytical expression to temperature-dependent Kirkwood-Fr?hlich dipole orientation parameter using the Boubaker Polynomials Expansion Scheme (BPES)

An analytical expression is proposed to the Kirkwood-Fr?hlich dipole orientation correlation parameter g. This parameter, which has been considered as a relevant guide to understanding the structuredness of supercritical fluids, had been always determined numerically. The advantage of the used protocol: the BPES, is to yield continuous and integrable expressions which can be easily incorporated in analytical models. The results have been compared to several precedent studies.     

Kinetic Analysis of Multi Enzyme Systems: A Case Study of the Closed System of Creatine Kinase, Hexokinase and Glucose 6-Phosphate Dehydrogenase

This paper describes a general methodology to handle closed multi enzyme systems using mixture of symbolic (which depends on the Gröbner Basis technique) and numerical computation methods. The applicability of the proposed method has been examined for the closed three-enzyme system of rabbit heart creatine kinase (EC 2.7.3.2), yeast hexokinase (EC 2.7.1.1) and human erythrocyte glucose 6-phosphate dehydrogenase (EC 1.1.1.49) using experimental data.