Ringing the initial Universe: the response of overdensity and transformed-density power spectra to initial spikes

We present an experiment in which we 'ring' a set of cosmological N-body-simulation initial conditions, placing spikes in the initial power spectrum at different wavenumber bins. We then measure where these spikes end up in the final conditions. In the usual overdensity power spectrum, most sensitive to contracting and collapsing dense regions, initial power on slightly non-linear scales (k ~ 0.3 h/Mpc) smears to smaller scales, coming to dominate the initial power once there. Log-density and Gaussianized-density power spectra, sensitive to low-density (expanding) and high-density regions, respond differently: initial spikes spread symmetrically in scale, both upward and downward. In fact, in the power spectrum of 1/(1 + {\delta}), spikes migrate to larger scales, showing the magnifying effect of voids on small-scale modes. These power spectra show much greater sensitivity to small-scale initial features. We also test the difference between an approximation of the Ly-{\alpha} flux field, and its Gaussianized form, and give a toy model that qualitatively explains the symmetric power spreading in Gaussianized-density power spectra. Also, we discuss how to use this framework to estimate power-spectrum covariance matrices. This can be used to track the fate of information in the Universe, that takes the form of initial degrees of freedom, one random spike per initial mode.Comment: Accepted to MNRAS Letters. 6 pages, 5 figure

SMS text pre-notification and delivery of reminder e-mails to increase response rates to postal questionnaires in the SUSPEND trial : a factorial design, randomised controlled trial

Acknowledgements SUSPEND was funded by the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme (project 80/71/01) and will be published in full in Health Technology Assessment. The Health Services Research Unit of the University of Aberdeen is funded in part by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates. The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the Chief Scientist Office, HTA programme, NIHR, National Health Service, or Department of Health. The authors thank the SUSPEND staff and participants, without whom this study would not have been possible.Peer reviewedPublisher PD

Critical branching processes in digital memcomputing machines

Memcomputing is a novel computing paradigm that employs time non-locality (memory) to solve combinatorial optimization problems. It can be realized in practice by means of non-linear dynamical systems whose point attractors represent the solutions of the original problem. It has been previously shown that during the solution search digital memcomputing machines go through a transient phase of avalanches (instantons) that promote dynamical long-range order. By employing mean-field arguments we predict that the distribution of the avalanche sizes follows a Borel distribution typical of critical branching processes with exponent $\tau= 3/2$. We corroborate this analysis by solving various random 3-SAT instances of the Boolean satisfiability problem. The numerical results indicate a power-law distribution with exponent $\tau = 1.51 \pm 0.02$, in very good agreement with the mean-field analysis. This indicates that memcomputing machines self-tune to a critical state in which avalanches are characterized by a branching process, and that this state persists across the majority of their evolution.Comment: 5 pages, 3 figure

“The Fall of the House of Usher”: Poe’s perverted perspective on the “Maimed King”

The themes of medieval literature had a profound effect on the works that would follow in later generations regardless of the writer’s recognition of this influence, and one can see the way Poe leaves traces of the popular medieval motif of the “Maimed King” in his short story, “The Fall of the House of Usher”. This thematic device, which predates the medieval period, gained prominence in the tales of King Arthur and the Grail Quest. Although there is no clear indication that Poe intentionally set out to create a gothic rendition of this traditional theme, that does not discount the possibility of “Usher” having been conditioned in some respect by this medieval notion. Through implementing a close reading of the story and comparing it to a framework of this conception of the “Maimed King”, this paper points out a number of striking similarities between the two, as well as demonstrates the far-reaching influence of medievalism in one of nineteenth-century America’s preeminent fiction writers, Edgar Allan Poe

Conceptualization and Application of Deep Learning and Applied Statistics for Flight Plan Recommendation

The Air Forces Pilot Training Next (PTN) program seeks a more efficient pilot training environment emphasizing the use of virtual reality flight simulators alongside periodic real aircraft experience. The PTN program wants to accelerate the training pace and progress in undergraduate pilot training compared to traditional undergraduate pilot training. Currently, instructor pilots spend excessive time planning and scheduling flights. This research focuses on methods to auto-generate the planning of in-flight events using hybrid filtering and deep learning techniques. The resulting approach captures temporal trends of user-specific and program-wide student performance to recommend a feasible set of graded flight events for evaluation in a student’s next training exercise to improve their progress toward fully qualified status

THE INDUSTRY HAS CHANGED, HAVE YOU? THE AGCO STORY

AGCO Corporation is a success story in the agricultural machinery sector. Utilizing marketing strategies of out-sourcing, cross-over selling, and a full line of products, AGCO markets its own way. In 7 years, AGCO has 18 brands sold through 7,000 dealerships in 140 countries. Acquisition and consolidation powered the growth of AGCO using nontraditional buyout financing. Herein lies its real success.Agribusiness, Industrial Organization,

The 8-13 micron observations of Titan

Narrow band observations of Titan at selected wavelengths in the 8-13 micron range show evidence for a strong temperature inversion and the existence of at least one more spectroscopically active component in the atmosphere in addition to H2 and CH4

Oral History Interview: Forrest Atkinson

During his interview, Forrest Atkinson reminisces about growing up on a farm in Cabell County, West Virginia. His father was a tobacco farmer and timber cutter. He focuses on food preservation processes and home entertainment, including music and books. He also focuses on changes in technology during his lifetime. In the audio clip provided, Mr. Atkinson discusses raising and selling tobacco.https://mds.marshall.edu/oral_history/1025/thumbnail.jp