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Inspired by the recent Democratic National Primary, we consider settings in which the members of a distributed population must balance their individual preferences over candidates with a requirement to quickly achieve collective unity. We formalize such settings as the “Democratic Primary Problem” (DPP) over an undirected graph, whose local structure models the social influences acting on

In one of his early papers Claude Berge proved a Helly-type theorem, which replaces the usual “nonempty intersection” condition with a “convex union” condition. Inspired by this we prove a fractional Helly-type result, where we assume that many (d+1)-tuples of a family of convex sets have a star-shaped union, and the conclusion is that many of the sets have a common point. We also investigate s...

This paper discusses evaluation in the context of public art and specifically of interactive digital art. The study reported is of ‘Light Logic’, an exhibition of retrospective and current drawings, paintings and interactive digital works by the second author. The study was conducted by Site Gallery Sheffield in association with UK and Australian researchers. A survey of evaluation practice amo...

abstract aims: the application of photocatalytic processes to remove heavy metals in aqueous solutions and industrial wastewater are regarded as extremely effective, clean and without producing waste methods. the goal of the present study was to investigate the photocatalytic activity of zno based on h-zsm-5 zeolite support. materials & methods: zno/h-zsm-5 composite synthesized by impregnation...

tungsten trioxide nanoparticles with two different sizes (average particle sizes about 50 and 80 nm) were prepared by the spray pyrolysis method. photo degradation of congo red (azo dye) showed that photo catalytic property of the as-prepared wo3 nanoparticles with average size about 80 nm is higher than the sample with average size about 50 nm. photo degradation of rhodamine b (cationic triary...

Titanium dioxide has been widely used for photo-catalytic and self-cleaning activities. In this study, TiO2 /SiO2 /Co nanocomposite was prepared by sol-gel method in the presence of Polyvinyl Pyrrolidone (PVP), and Hydroxyl Propyl Cellulose (HPC) as additives, and characterized by IR spectra, Scanning Electron Microscopy (SEM), Energy Dispersive Analytical X-Ray (EDAX), and X-Ray Diffraction (X...

That people were interested in the subject, the plight of the very young, unmarried mother, can hardly be denied?the National Council turned away half the people who applied and the hall was still bursting at the sides. The speakers were all people who, over the last 25 years, have each, in their own way, done much to salvage a lot of human unhappiness. Much of the work they do has started in t...