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This is a collection of the reports on the Annenberg national surveys that explored Americans' knowledge and opinions about the new digital-marketing world that was becoming part of their lives. So far we’ve released seven reports on the subject, in 1999, 2000, 2003, 2005, 2009, 2010, and 2012. The reports raised or deepened a range of provocative topics that have become part of public, policy, and industry discourse. In addition to these reports, I’ve included three journal articles — from I/S, New Media & Society and the Journal of Consumer Affairs — that synthesize some of the findings and place them into policy frameworks. The journals have kindly allowed reproduction for this purpose.

A hybridized genetic algorithm is proposed to determine a repair schedule for a network of bridges. The schedule aims for the lowest overall cost while maintaining each bridge at satisfactory quality conditions. Appreciation, deterioration, and cost models are employed to model real-life behaviour. To reduce the computational time, pre-processing algorithms are used to determine an initial genome that is closer to the optimal solution rather than a randomly generated genome. A post-processing algorithm that locates a local optimal solution from the output of the genetic algorithm is employed for further reduction of computational costs. Experimental work was carried out to demonstrate the effectiveness of the proposed approach in determining the bridge repair schedule. The addition of a pre-processing algorithm improves the results if the simulation period is constrained. If the simulation is ran sufficiently long all pre-processing algorithms converge to the same optimal solution. If a pre-processing algorithm is not implemented, however, the simulation period increases significantly. The cost and deterioration tests also indicate that certain pre-processing algorithms are better suited for larger bridge networks. The local search performed on the genetic algorithm output is always seen as a positive add-on to further improve results. Scopus

The volatile and hygroscopic properties of ammonium sulphate seeded and un-seeded secondary organic aerosol (SOA) derived from the photo-oxidation of atmospherically relevant concentrations of ?-pinene were studied. The seed particles were electrospray generated ammonium sulphate ((NH4)2SO4) having diameters of approximately 33 nm with a quasi-mono-disperse size distribution (geometric standard deviation ?g=1.3). The volatile and hygroscopic properties of both seeded and unseeded SOA were simultaneously measured with a VH-TDMA (volatility ? hygroscopicity tandem differential mobility analyzer). VH-TDMA measurements of unseeded SOA show a decrease in the hygroscopic growth (HGF) factor for increased volatilisation temperatures such that the more volatile compounds appear to be more hygroscopic. This is opposite to the expected preferential evaporation of more volatile but less hygroscopic material, but could also be due to enhanced oligomerisation occurring at the higher temperature in the thermodenuder. In addition, HGF measurements of seeded SOA were measured as a function of time at two relative humidities, below (RH 75%) and above (RH 85%) the deliquescence relative humidity (DRH) of the pure ammonium sulphate seeds. As these measurements were conducted during the onset phase of photo-oxidation, during particle growth, they enabled us to find the dependence of the HGF as a function of the volume fraction of the SOA coating. HGF's measured at RH of 85% showed a continuous decrease as the SOA coating thickness increased. The measured growth factors show good agreements with ZSR predictions indicating that, at these RH values, there are only minor solute-solute interactions. At 75% RH, as the SOA fraction increased, a rapid increase in the HGF was observed indicating that an increasing fraction of the (NH4)2SO4 is subject to a phase transition, going into solution, with an increasing volume fraction of SOA. To our knowledge this is the first time that SOA derived from photo-oxidised ?-pinene has been shown to affect the equilibrium water content of inorganic aerosols below their DRH. For SOA volume fractions above ~0.3 the measured growth factor followed roughly parallel to the ZSR prediction based on fully dissolved (NH4)2SO4 although with a small difference that was just larger than the error estimate. Both incomplete dissolution and negative solute-solute interactions could be responsible for the lower HGF observed compared to the ZSR predictions.