Multi-criteria group decision making based on Archimedean power partitioned Muirhead mean operators of q-rung orthopair fuzzy numbers.

Two critical tasks in multi-criteria group decision making (MCGDM) are to describe criterion values and to aggregate the described information to generate a ranking of alternatives. A flexible and superior tool for the first task is q-rung orthopair fuzzy number (qROFN) and an effective tool for the second task is aggregation operator. So far, nearly thirty different aggregation operators of qROFNs have been presented.

Mathematics for modern precision engineering.

The aim of precision engineering is the accurate control of geometry. For this reason, mathematics has a long association with precision engineering: from the calculation and correction of angular scales used in surveying and astronomical instrumentation to statistical averaging techniques used to increase precision. This study illustrates the enabling role the mathematical sciences are playing in precision engineering: modelling physical processes, instruments and complex geometries, statistical characterization of metrology systems and error compensation.

Estimation of the solute diffusion coefficient of a dilute liquid alloy: static structure factor and isothermal compressibility estimates obtained using the rational function approximation of the radial distribution.

A simple method for estimating the mass diffusion coefficient of a dilute binary liquid alloy that sequentially uses experimental data for the static structure factor and isothermal susceptibility of the solvent is presented, as well as another using the static structure factor alone and a method using the isothermal susceptibility alone. A fourth method that simultaneously uses the static structure factor and isothermal susceptibility is also noted. Of significance is the fact that these methods do not require information about the interatomic potential.

Solute diffusion in nonionic liquids--effects of gravity.

We have been engaged in examining the influence of gravity on the results of experiments to measure the variation of solute diffusion coefficients (D) with temperature (T) in fused metals and semimetals since our first STS flights in 1992. These early experiments, conducted with the in situ g-jitter of the shuttle, showed the near-parabolic variation of D with T reported by others. However, with the aid of the Canadian Space Agency's microgravity isolation mount (MIM) to isolate the diffusion facility from the existing g-jitter of the Russian space station MIR, we showed that in all the alloy systems and over the temperature range studied, D increased linearly with T.

Asthma is a risk factor for acute chest syndrome and cerebral vascular accidents in children with sickle cell disease.

BACKGROUND: Asthma and sickle cell disease are common conditions that both may result in pulmonary complications. We hypothesized that children with sickle cell disease with concomitant asthma have an increased incidence of vaso-occlusive crises that are complicated by episodes of acute chest syndrome. METHODS: A 5-year retrospective chart analysis was performed investigating 48 children ages 3-18 years with asthma and sickle cell disease and 48 children with sickle cell disease alone.