Dynamical Systems on Networks: A Tutorial

We give a tutorial for the study of dynamical systems on networks. We focus especially on "simple" situations that are tractable analytically, because they can be very insightful and provide useful springboards for the study of more complicated scenarios. We briefly motivate why examining dynamical systems on networks is interesting and important, and we then give several fascinating examples and discuss some theoretical results. We also briefly discuss dynamical systems on dynamical (i.e., time-dependent) networks, overview software implementations, and give an outlook on the field.Comment: 39 pages, 1 figure, submitted, more examples and discussion than original version, some reorganization and also more pointers to interesting direction

Evaluating change in professional behaviour: issues in design and analysis

Implementing the findings of research to change the behaviour of health care professionals has become an increasingly prominent issue. However, designing valid studies to evaluate different methods of achieving changes requires considerable care and there are a number of pitfalls evident from published previous work. The various steps in the development of an implementation method and issues arising are explored in this text. Aspects include conceptualisation, essential background work, a structured development process, the relative merits of randomised and non-equivalent group designs, the unit of analysis, the role of multi-level models, block designs, economic analysis, and the content or message to be disseminated. An ongoing, large, randomised trial of educational outreach visits by trained pharmacists is used to illustrate some of the issues.behavioural change, implementation methods, economic evaluation, design of trials

Active Region Moss: Doppler Shifts from Hinode/EIS Observations

Studying the Doppler shifts and the temperature dependence of Doppler shifts in moss regions can help us understand the heating processes in the core of the active regions. In this paper we have used an active region observation recorded by the Extreme-ultraviolet Imaging Spectrometer (EIS) onboard Hinode on 12-Dec-2007 to measure the Doppler shifts in the moss regions. We have distinguished the moss regions from the rest of the active region by defining a low density cut-off as derived by Tripathi et al. (2010). We have carried out a very careful analysis of the EIS wavelength calibration based on the method described in Young et al. (2012). For spectral lines having maximum sensitivity between log T = 5.85 and log T = 6.25 K, we find that the velocity distribution peaks at around 0 km/s with an estimated error of 4-5 km/s. The width of the distribution decreases with temperature. The mean of the distribution shows a blue shift which increases with increasing temperature and the distribution also shows asymmetries towards blue-shift. Comparing these results with observables predicted from different coronal heating models, we find that these results are consistent with both steady and impulsive heating scenarios. However, the fact that there are a significant number of pixels showing velocity amplitudes that exceed the uncertainty of 5 km s$^{-1}$ is suggestive of impulsive heating. Clearly, further observational constraints are needed to distinguish between these two heating scenarios.Comment: 21 pages (single column), 7 figures, Accepted for Publication in The Astrophysical Journa

Social Enterprise Systems Engineering

AbstractThis conceptual article advances a theory of Social-Enterprise Systems-Engineering (SESE) as an applied discipline and as an addition to the development intervention field. It will elaborate the SESE construct, examine the relationships between its constituent components, present evidence of its potential benefits and then provide suggestions for future research

Overview of the Systems Special Investigation Group investigation

The Long Duration Exposure Facility (LDEF) carried a remarkable variety of electrical, mechanical, thermal, and optical systems, subsystems, and components. Nineteen of the fifty-seven experiments flown on LDEF contained functional systems that were active on-orbit. Almost all of the other experiments possessed at least a few specific components of interest to the Systems Special Investigation Group (Systems SIG), such as adhesives, seals, fasteners, optical components, and thermal blankets. Almost all top level functional testing of the active LDEF and experiment systems has been completed. Failure analysis of both LDEF hardware and individual experiments that failed to perform as designed has also been completed. Testing of system components and experimenter hardware of interest to the Systems SIG is ongoing. All available testing and analysis results were collected and integrated by the Systems SIG. An overview of our findings is provided. An LDEF Optical Experiment Database containing information for all 29 optical related experiments is also discussed

Day Four: A Rescuer\u27s Account of a Hiker\u27s Baffling Survival

In early of May 2009, teams from New Hampshire search-and-rescue organizations try to locate a man missing for four days below the Franconia Ridge. The outcome is astonishing