Harmonic equiangular tight frames comprised of regular simplices

An equiangular tight frame (ETF) is a sequence of unit-norm vectors in a Euclidean space whose coherence achieves equality in the Welch bound, and thus yields an optimal packing in a projective space. A regular simplex is a simple type of ETF in which the number of vectors is one more than the dimension of the underlying space. More sophisticated examples include harmonic ETFs which equate to difference sets in finite abelian groups. Recently, it was shown that some harmonic ETFs are comprised of regular simplices. In this paper, we continue the investigation into these special harmonic ETFs. We begin by characterizing when the subspaces that are spanned by the ETF's regular simplices form an equi-isoclinic tight fusion frame (EITFF), which is a type of optimal packing in a Grassmannian space. We shall see that every difference set that produces an EITFF in this way also yields a complex circulant conference matrix. Next, we consider a subclass of these difference sets that can be factored in terms of a smaller difference set and a relative difference set. It turns out that these relative difference sets lend themselves to a second, related and yet distinct, construction of complex circulant conference matrices. Finally, we provide explicit infinite families of ETFs to which this theory applies

Research on elemental abundances in meteoritic and terrestrial matter Summary progress report, 1 Sep. 1964 - 31 Aug. 1965

Element abundances determined by instrumental neutron activation analysis technique in individual chondrules separated from certain chondritic meteorite

Abundances of trace elements Na, Sc, Cr, Mn, Fe, Co, and Cu in chondrules and meteorites in IN meteorites and terrestrial matter and U in type I carbonaceous chondrites Quarterly progress report, 1 Mar. - 15 Jun. 1966

Abundances of sodium, scandium, chromium, iron, manganese, cobalt, copper, indium, and uranium in chondrules, chondrites, and meteorites determined by neutron activation analysi

Field testing of strategies for fire blight control in organic fruit growing

In organic fruit growing effective control strategies are needed to prevent blossom infections by the fire blight pathogen Erwinia amylovora. Many potential control agents are under discussion and have been tested in vitro and in vivo. 19 out of 27 tested preparations showed a high efficacy against E. amylovora in vitro. Nevertheless, on detached apple blossoms only 7 of them led to a symptom reduction by more than 50%. In six field trials conducted according to the EPPO guideline PP1/166(3) BlossomProtect (82%), Myco-sin (65%) and Funguran (58%) had the highest efficiency. In 2006 and 2007, strategies to integrate BlossomProtect in spray schedules of organic apple production have been tested. The use of sulphur or lime-sulphur before or after BlossomProtect did not influence the efficiency of BlossomProtect, which showed that fire blight control is possible without compromising apple scab control. The addition of Cutisan to BlossomProtect reduced fruit russet. An alternating use of BlossomProtect and Myco-sin was shown to be possible

Fission-Fragment Mass Distribution and Particle Evaporation at low Energies

Fusion-fission dynamics is investigated with a special emphasis on fusion reactions at low energy for which shell effects and pairing correlations can play a crucial role leading in particular to multi-modal fission. To follow the dynamical evolution of an excited and rotating nucleus we solve a 2-dimensional Langevin equation taking explicitly light-particle evaporation into account. The confrontation theory-experiment is demonstrated to give interesting information on the model presented, its qualities as well as its shortcomings.Comment: 19 pages, latex, 24 eps-figure

Activation analysis for selected elements in micrometeorites and hypervelocity projectiles Annual progress report, 1 Jul. 1969 - 1 Jul. 1970

Activation analysis to identify materials for use as catcher for micrometeoroid

Abundances of Na, Sc, Cr, Mn, Fe, Co, and Cu in chondrules, Na, Mn, and Cu in meteorites, and In in meteoritic and terrestrial matter Quarterly progress report, 1 Dec. 1965 - 28 Feb. 1966

Element abundance in chondrules and meteorites measured by instrumental neutron activation analysis, and indium behavior in chondrite