Tagger's delight? Disclosure and liking in Facebook: the effects of sharing photographs amongst multiple known social circles

The present work identifies the relationship between sharing photographs with different depictions in Facebook on relationship quality, which varies depending on the type of target sharing the photographs. With over 1 billion active users, disclosure on Facebook is frequent, considered a norm of online interaction, and actively encouraged by site providers. The extant academic literature identifies Facebook as an effective tool to connect with known and unknown others, and identifies the differences in sharing behaviour when users are aware of their audience. Operating within a lowest common denominator approach to disclosure on Facebook, the present work identifies the potential consequences to personal relationships when sharing day-to-day information. Results found from a sample of 508 Facebook users suggests individuals should actively adjust their privacy settings to ensure that even amongst flattened information – i.e. that deemed appropriate for release to all target types – disclosure does not harm current and potential relationships. Implications for, users, academic theory and disclosure practice are discussed

VyZX: Formal Verification of a Graphical Quantum Language

Mathematical representations of graphs often resemble adjacency matrices or lists, representations that facilitate whiteboard reasoning and algorithm design. In the realm of proof assistants, inductive representations effectively define semantics for formal reasoning. This highlights a gap where algorithm design and proof assistants require a fundamentally different structure of graphs, particularly for process theories which represent programs using graphs. To address this gap, we present VyZX, a verified library for reasoning about inductively defined graphical languages. These inductive constructs arise naturally from category theory definitions. A key goal for VyZX is to Verify the ZX-calculus, a graphical language for reasoning about quantum computation. The ZX-calculus comes with a collection of diagrammatic rewrite rules that preserve the graph's semantic interpretation. We show how inductive graphs in VyZX are used to prove the correctness of the ZX-calculus rewrite rules and apply them in practice using standard proof assistant techniques. VyZX integrates easily with the proof engineer's workflow through visualization and automation.Comment: 28 pages, 26 figure

Classifying Data Deposited by Scientists into a Library\u27s Data Repository

In 2014, a team of librarians at Brown University began a concerted effort to ingest, describe, and publish scientific data and digital scholarship into the Brown Library’s data repository, the Brown Digital Repository (BDR). The Library targeted outreach towards student, staff, and faculty researchers in the sciences to encourage them to deposit their digital scholarship, such as digital research products related to grants and data related to their publications, into the BDR. This poster presents a snapshot of the types of scholarship that were deposited by scientists during a 2-year period and classifies the nature of these digital objects. The authors looked at the total number of files deposited by scientists over this period and created a tool to classify and categorize these objects in order to characterize the nature of digital scholarship that scientists were depositing. The instrument classified these objects into several categories and subcategories based on concrete criteria. The first category described digital objects associated with a publication. Data in this category were further classified into the subcategories “underlying data” and “supplementary data”. Underlying data included files that contained the results reported in the publication, files necessary for the peer review of the paper’s reported results and/or necessary for replication or reproduction of research results, such as code that was used to analyze results. The supplementary data were files accompanying a publication, including tables, graphs or visualizations that were not able to be included in the paper or were referenced by authors. The second category was files created by student, staff or faculty researchers not related to a publication but could stand alone as scholarly products equivalent to a publication, such as research posters, animations, visualizations, or software. The last category described digital collections, and included three subcategories: legacy data, digital libraries, and grants. Legacy data were digital products published by retiring faculty or faculty nearing the end of their research careers. Digital libraries included the published collections of scientific data not associated with a single publication. These collections could be published by individual researchers, a collaborative team, labs, and/or departments, and their purpose is to make these items available for other researchers to access and reuse. Lastly, the subcategory grant data contained collections of scientific data and/or other types of digital scholarship associated with a funded-project. These collections could be published by individual researchers, a collaborative team, labs, and/or departments, and the purpose is to disseminate items resulting from sponsored research and/or make these resulting grant-funded digital objects available for other researchers and/or the public

High level design proof of a reliable computing platform

The main objectives are: to establish hardware/software platform for ultra-reliable computing; to use fault tolerant computer architecture; to use formal methods to prevent design and implementation errors; and to construct reliability model to quantify reliability estimate. The results show that: ultra-reliable control systems are hard to achieve; simple fault tolerant design is postulated; formal specification of design is constructed; and preliminary correctness proofs are obtained

Tidal streams in a MOND potential: constraints from Sagittarius

We compare orbits in a thin axisymmetric disc potential in MOND to those in a thin disc plus near-spherical dark matter halo predicted by a $\Lambda$CDM cosmology. Remarkably, the amount of orbital precession in MOND is nearly identical to that which occurs in a mildly oblate CDM Galactic halo (potential flattening q=0.9), consistent with recent constraints from the Sagittarius stream. Since very flattened mass distributions in MOND produce rounder potentials than in standard Newtonian mechanics, we show that it will be very difficult to use the tidal debris from streams to distinguish between a MOND galaxy and a standard CDM galaxy with a mildly oblate halo. If a galaxy can be found with either a prolate halo, or one which is more oblate than $q \sim 0.9$ this would rule out MOND as a viable theory. Improved data from the leading arm of the Sagittarius dwarf - which samples the Galactic potential at large radii - could rule out MOND if the orbital pole precession can be determined to an accuracy of the order of $\pm 1^o$.Comment: 7 pages, 3 figures. Final version accepted for publication in MNRAS. The modelling of the Sagittarius stream has been improved, but otherwise the conclusions remain the sam

An Extremely Bright Echo Associated With SN 2002hh

We present new, very late-time optical photometry and spectroscopy of the interesting Type II-P supernova, SN 2002hh, in NGC 6946. Gemini/GMOS-N has been used to acquire visible spectra at six epochs between 2004 August and 2006 July, following the evolution of the SN from age 661 to 1358 days. Few optical spectra of Type II supernovae with ages greater than one year exist. In addition, g'r'i' images were acquired at all six epochs. The spectral and photometric evolution of SN 2002hh has been very unusual. Measures of the brightness of this SN, both in the R and I bands as well as in the H-alpha emission flux, show no significant fading over an interval of nearly two years. The most straightforward explanation for this behavior is that the light being measured comes not only from the SN itself but also from an echo off of nearby dust. Echoes have been detected previously around several SNe but these echoes, at their brightest, were ~8 mag below the maximum brightness of the SN. At V~21 mag, the putative echo dominates the light of SN 2002hh and is only ~4 mag below the outburst's peak brightness. There is an estimated 6 magnitudes of total extinction in V towards SN 2002hh. The proposed explanation of a differential echo/SN absorption is inconsistent with the observed BVRI colors.Comment: 24 pages, 6 figures. Accepted for publication in the Ap