Modelling the CPI using a lognormal diffusion process and implications on forecasting inflation

The Maximum Likelihood estimator is used within a lognormaldiffusion process and closed form analytical solutions are obtained.The monthly CPI forecasts are estimated for the period between1970 and 2002. The quarterly estimates of inflation rates areobtained from monthly forecasts rather than from quarterly data.This has significantly improved the estimates of inflation rates.The model also produced a superior fit as compared to randomwalk and GARCH(p,q)-M models. The adopted approach is foundto be simple, economical and generally suitable for modellingstochastic processes that reflect aggregation over time stemmingfrom many factors, and in which the transition path betweenconsecutive states is relatively smooth.     

A simple multi-scroll hyperchaotic system

We propose a simple autonomous hyperchaotic system that can generate multi-scroll attractors. The proposed system has a canonical structure, one control parameter, and a switching-type nonlinearity. If multiple breakpoints are added to the system nonlinearity, multi-scroll behavior can be obtained. We numerically demonstrate hyperchaotic behavior of the proposed system, under different nonlinearities, as its control parameter is changed. Furthermore, we study hyperchaos in the proposed system when it assumes a fractional order, and demonstrate that hyperchaotic behavior can be obtained in systems less than fourth order. Throughout the study, hyperchaos is verified by examining the Lyapunov spectrum, where the presence of multiple positive Lyapunov exponents in the spectrum is indicative of hyperchaos.     

Weighted ebyev-Ostrowski type inequalities

In account of the famous ebyev inequality,a rich theory has appeared in the literature.We establish some new weighted ebyev type integral inequalitíes.Our proofs are of independent interest and provide new estimates on these types of inequalities.     

Existence of solutions for generalized implicit vector variational-like inequalities

In this paper, we introduce a new class of generalized implicit vector variational-like inequalities in Hausdorff topological vector spaces and Banach spaces which contain implicit vector equilibrium problems, implicit vector variational inequalities and implicit vector complementarity problems as special cases. We derive some new results by using the KKM–Fan theorem, under compact and noncompact assumptions on underlying convex sets.     

Natural radioactivity in marble stones- Jordan

Natural radioactivity has been measured in marble stone samples collected from Dabaa'h, Ajloun and Azrak areas using a gamma spectroscopy technique. The measured ²²⁶Ra activities in the stones collected from Dabaa'h quarries varied from 264.9 Bq kg⁻¹ to 369.5 Bq kg⁻¹. In samples from Ajloun and Azrak the maximum values of ²²⁶Ra were 28.3 Bq kg⁻¹ and 23.41 Bq kg⁻¹, respectively. The measured values of ²³²Th were less than 17.89 Bq kg⁻¹. The average values of the radium equivalent activities as well as external and internal hazard indices were also calculated. It was observed that for marble stones from Dabaa'h area, estimated average value of the external hazard index is 0.873 and that of internal hazard index is 1.71.     

Hyperfine structure and isotope shift of the neutron-rich barium isotopes139–146Ba and148Ba

The hyperfme structure and isotope shift in the 6s ² S _1/2?6p ²P_3/2 line of Ba II (455.4 nm) have been measured by collinear fast-beam laser spectroscopy for the neutron-rich isotopes^139–146Ba and¹⁴⁸Ba. Nuclear moments and mean square charge radii of these isotopes have been recalculated. The isotope shift of the isotope¹⁴⁸Ba (T_1/2=0.64 s) could be studied for the first time, yieldingδ〈r²〉^138,148=1.245(3) fm².     

Effect of annealing on the electrical properties and refractive index of HgI2 single crystals

The effect of annealing on the electrical properties and the refractive index of red mercuric iodide (HgI₂) single crystals is investigated. The ac-impedance and phase angle were measured in the frequency range from 100 Hz to 10 kHz at different annealing temperatures. The ac-conductivity, dielectric constants, loss tangent and the refractive index as a function of frequency are determined. The results are discussed in terms of structural changes taking place as a result of the heat treatment of the HgI₂ single crystals.     

Design and fabrication of low-cost X-ray mirrors

Traditional X-ray mirrors made from Zerodur and silicon carbide are quite expensive because of the fabrication cost involved in achieving a very high surface finish of the order of 15 Å or better. The cost of X-ray mirrors can be greatly reduced by using replication methods for producing the grazing-incidence type mirrors. This paper presents the optical and optomechanical design for a Wolter type I mirror and its mount, and the fabrication method used to produce a low-cost replicated nickel mirror. The finite element analysis results for this mirror are also presented. The design and fabrication steps for the aluminium master mandrel used for replication are also discussed. A surface finish of better than 15 Å was achieved for a such an electroformed mirror with a wall thickness of only 1 mm.     

Kinetics and mechanism of copper(II) induced decomposition of 9-diazofluorene

The kinetics and products of the decompositon of 9-diazofluorene by copper(II) tetrafluoroborate in acetonitrile solvent have been investigated. The reaction is first order with respect to both 9-diazofluorene and copper(II) tetrafluoroborate. A reaction mechanism has also been proposed.     

Adoucissement des eaux calciques par échange d''ions transmembranaire à travers des membranes homogenes obtenues par greffage radiochimique

The potential application of DONNAN dialysis to water softening has been studied. The selective transportation of calcium and alkaline-earth ions through a cationic membrane appeared to be an interesting process, since materials with both optimal exchange capacity and transportation properties exist now.

Preliminary investigations allowed us to optimize some of these materials, as well as the conditions of their use. Thus we have found that for the membranes handled, the 3.10-2 M concentration of brine represented the best compromise between the extraction of calcium and the leakage of chlorine through the membrane (relating to the water to be softened).

We also observed that for a low and a medium flow, the extraction rate was high enough to allow the release of calcium at a rate comparable to the classical ion-exchange process using a resin bed.