Piloted-simulation study of effects of vortex flaps on low-speed handling qualities of a Delta-wing airplane

A piloted-simulation study was conducted to investigate the effects of vortex flaps on low-speed handling qualities of a delta-wing airplane. The simulation math model was developed from wind tunnel tests of a 0.15 scale model of the F-106B airplane. Pilot evaluations were conducted using a six-degree-of-freedom motion base simulator. The results of the investigation showed that the reduced static longitudinal stability caused by the vortex flaps significantly degraded handling qualities in the approach-to-landing task. Acceptable handling qualities could be achieved by limiting the aft center-of-gravity location, consequently reducing the operational envelope of the airplane. Further improvement were possible by modifying the flight control force-feel system to reduce pitch-control sensitivity

Level-Screening Designs for factors with many levels

We consider designs for f factors each at m levels, where f is small but m is large. Main effect designs with mf experimental points are presented. For two factors, two types of designs are investigated, termed sawtooth and dumbbell designs, based on a graphical representation. For three factors, cyclic sawtooth designs are considered. The paper seeks optimal and near optimal designs which involve factors with many levels but few observations. It also investigates issues of robustness when as much as one third of the data is structurally missing. An important area of application is in screening for drug discovery and we compare our designs with others using a published data set with two factors each with fifty levels, where the dumbbell design outperforms others and is an example of an inherently unbalanced design dominating more balanced designs

Nanofibrous Biocomposite Prosthetic Vascular Graft

The present invention provides a bioactive, small-diameter (typically less than 6 mm in internal diameter) vascular graft prosthesis, and is a textile conduit preferably manufactured using a novel electrospinning perfusion methodology. One preferred embodiment is a nanofibrous biocomposite textile conduit which comprises a prepared liquid admixture of polyester (Dacron), a biodurable implantable synthetic polymer, and Type IV collagen, an extracellular matrix protein. This prepared admixture and blending of diverse fibrous matter is utilized in a novel electrospinning perfusion process to form a small-diameter (less than 6 mm) fabricated textile conduit, a discrete article of manufacture, which then serves as an antecedent tangible workpiece for a subsequently-made prosthetic vascular graft construct

Electrospinning Process for Making a Textile Suitable for use as a Medical Article

The present invention is a bioactive, nanofibrous material construct which is manufactured using a unique electrospinning perfusion methodology. One embodiment provides a nanofibrous biocomposite material formed as a discrete textile fabric from a prepared liquid admixture of (i) a non-biodegradable durable synthetic polymer; (ii) a biologically active agent; and (iii) a liquid organic carrier. These biologically-active agents are chemical compounds which retain their recognized biological activity both before and after becoming non-permanently bound to the formed textile material; and will become subsequently released in-situ as discrete freely mobile agents from the fabric upon uptake of water from the ambient environment