We investigate the problem of minimizing the moment of inertia among convex surfaces in R having a specified surface area. First we prove a minimizing surface exists, and derive a necessary condition holding at points of positive curvature. Then we show that an equilateral triangular prism is the optimal triangular prism, that the cube is the optimal rectangular prism, and that the sphere is (l...

Understanding flow localization in materials containing high concentrations of Stacking Fault Tetrahedra (SFT’s) depends on delineation of the mechanisms by which they are destroyed as effective dislocation obstacles. The elastic interaction between glissile dislocations and SFT’s in FCC metals is examined, both analytically and numerically. Numerical calculations are performed for both full an...

Normal saline instillation is used by health professionals during the treatment of intubated patients within the intensive care unit, usually to enhance sputum yield. Its use is controversial; detrimental effects have been documented and evidence of any benefit is limited. Some studies have suggested routine use be discontinued. This study investigates the use of normal saline instillation in t...

We present a new shape measure for tetrahedral elements that is optimal in the sense that it gives the distance of a tetrahedron from the set of inverted elements. This measure is constructed from the condition number of the linear transformation between a unit equilateral tetrahedron and any tetrahedron with positive volume. We use this shape measure to formulate two optimization objective fun...

Particle shape plays a crucial role in determining packing characteristics. Real particles in nature usually have rounded corners. In this work, we systematically investigate the rounded corner effect on the dense packings of spherotetrahedral particles. The evolution of dense packing structure as the particle shape continuously deforms from a regular tetrahedron to a sphere is investigated, st...

Employing a method of distance geometry, we present a symbolic solution to the following problem: express the edge-lengths of a tetrahedron in terms of its heights and widths.

. 9 lnt:J-oo.uction I •••••••••••••••••••••••••••••••••••••••••••••••••••••••• I ••••••••••• 10 Discussion and Results 14 I Conclusions.... I..................................................................................................................... 28 Expe.rimental Ill....... .. 30 tI tI I t1 , •• •••• Appendix A: Publication in Tetrahedron Letters 2002 37 References 3S Appendix B: Sp...

Molecular dynamics (MD) simulations have been used to study the effect of Na ions on structure properties CaO–SiO2–Na2O melts. The short-range and medium-range in this are consistent with existing data. replacement Ca2+ Na+ melts has almost no degree polymerization distribution bond angles Si–O tetrahedron. From micro perspective, enhance mobility by multiple ways. Firstly, modification melt ne...