Synchronising C/C++ and POWER

Shared memory concurrency relies on synchronisation primitives: compare-and-swap, load-reserve/store-conditional (aka LL/SC), language-level mutexes, and so on. In a sequentially consistent setting, or even in the TSO setting of x86 and Sparc, these have well-understood semantics. But in the very relaxed settings of IBM®, POWER®, ARM, or C/C++, it remains surprisingly unclear exactly what the programmer can depend on. This paper studies relaxed-memory synchronisation. On the hardware side, we give a clear semantic characterisation of the load-reserve/store-conditional primitives as provided by POWER multiprocessors, for the first time since they were introduced 20 years ago; we cover their interaction with relaxed loads, stores, barriers, and dependencies. Our model, while not officially sanctioned by the vendor, is validated by extensive testing, comparing actual implementation behaviour against an oracle generated from the model, and by detailed discussion with IBM staff. We believe the ARM semantics to be similar. On the software side, we prove sound a proposed compilation scheme of the C/C++ synchronisation constructs to POWER, including C/C++ spinlock mutexes, fences, and read-modify-write operations, together with the simpler atomic operations for which soundness is already known from our previous work; this is a first step in verifying concurrent algorithms that use load-reserve/store-conditional with respect to a realistic semantics. We also build confidence in the C/C++ model in its own terms, fixing some omissions and contributing to the C standards committee adoption of the C++11 concurrency model

Effects on Fatigue of Applying Titanium Nitride Coating to 17-4 PH Stainless Steel

Honorable Mention Winner Surface coatings when applied to metals have many useful applications such as improving the biocompatibility and resistance to corrosion and wear. In this study, the effect of thickness of titanium nitride (TiN) on 17-4 precipitation hardened (PH) stainless steel under cyclic (i.e. fatigue) loading is investigated. TiN are applied to wrought 17-4 PH stainless steel using physical vapor deposition (PVD) technique in a low-pressure vacuum chamber filled with a mixture of inert argon and nitrogen gases with a ratio of 10:1. In addition, these specimens are subjected to two different vapor durations, but a constant voltage and pressure, to obtain different coating thicknesses. The fatigue resistance of 17-4 PH stainless steel specimens with TiN layer is obtained from rotating bending fatigue tests with constant stress levels which correlated to 75%, 50%, and 25% of the ultimate tensile strength. Failure analysis of the specimens were conducted using a scanning electron microscope (SEM) and an optical microscope to view the topography of the fracture surface and the thickness of the deposited TiN layer. The study expects that an increase in fatigue life of the specimens will result from increasing the thickness of the TiN layer due to an improvement in the hardness of the surface

Terrain Park Injuries

Background: This study examined demographics, injury pattern, and hospital outcome in patients injured in winter resort terrain parks.Methods: The study included patients >12 years of age who presented to a regional trauma center with an acute injury sustained at a winter resort. Emergency department (ED) research assistants collected patient injury and helmet use information using a prospectively designed questionnaire. ED and hospital data were obtained from trauma registry and hospital records.Results: Seventy-two patients were injured in a terrain park, and 263 patients were injured on non-terrain park slopes. Patients injured in terrain parks were more likely to be male [68/72 (94%) vs. 176/263 (67%), p<0.0001], younger in age [23 ± 7 vs. 36 ± 17, p<0.0001], live locally [47/72 (65%) vs. 124/263 (47%), p=0.006], use a snowboard [50/72 (69%) vs. 91/263 (35%), p<0.0001], hold a season pass [46/66 (70%) vs. 98/253 (39%), p<0.0001], and sustain an upper extremity injury [29/72 (40%) vs. 52/263 (20%), p<0.001] when compared to patients injured on non-terrain park slopes. There were no differences between the groups in terms of EMS transport to hospital, helmet use, admission rate, hospital length of stay, and patients requiring specialty consultation in the ED.Conclusions: Patients injured in terrain parks represent a unique demographic within winter resort patrons. Injury severity appears to be similar to those patients injured on non-terrain park slopes.[West J Emerg Med. 2009;10(4):257-262.

Facebook reactions : how are they used and which personality factors predict their use?

The recent expansion of Facebook’s ‘like’ to six emotional reactions (love, haha, wow, sad, angry) represents the first update related to feedback, allowing users to respond to shared content, in almost a decade. We surveyed 260 Facebook users to investigate how reactions are utilized, and in response to what type of online content (status updates, pictures, links, timehops and events). We also measured Big Five personality and narcissism. Users were most likely to react using like, followed by positive reactions (love, haha, wow), and were least likely to employ the negative reactions sad and angry. Status updates and pictures were the types of content most likely to be responded to, and events least likely. Neuroticism, extraversion and openness positively predicted, and narcissism negatively predicted, utilization of reactions, and likelihood of responding. Established online norms and the affordances of Facebook features provide explanation for the findings

Use of Transformer-Based Models for Word-Level Transliteration of the Book of the Dean of Lismore

The Book of the Dean of Lismore (BDL) is a 16th-century Scottish Gaelic manuscript written in a non-standard orthography. In this work, we outline the problem of transliterating the text of the BDL into a standardised orthography, and perform exploratory experiments using Transformer-based models for this task. In particular, we focus on the task of word-level transliteration, and achieve a character-level BLEU score of 54.15 with our best model, a BART architecture pre-trained on the text of Scottish Gaelic Wikipedia and then fine-tuned on around 2,000 word-level parallel examples. Our initial experiments give promising results, but we highlight the shortcomings of our model, and discuss directions for future work

Concert recording 2017-04-26

[Track 1]. Fantazia / Orlando Gibbons arranged by Fred Hemke -- [Track 2-3]. Quartette (Allegro de concert) / Caryl Florio -- [Track 4]. O magnum mysterium / Morten Lauridsen arranged by Chase Shumsky -- [Track 5]. Petite symphonie. Scherzo / Charles Gounod arranged by Aaron M. Durst -- [Track 6]. Grainger set. Mock Morris / Percy Aldridge Grainger arranged by Gary Bricault -- [Track 7]. Grainger set. Two British folk settings. I. Mo nighean dubh [Track 8]. II. The hunter in his career / Percy Aldridge Grainger arranged by Chalon Ragsdale -- [Track 9]. Molly on the shore / Percy Aldridge Grainger arranged by Jacques Larocque -- [Track 10]. The great gate of Kiev / Modest Mussorgsky and Maurice Ravel arranged by B.L. Bruske

Do You See What I See?:Quantifying Inter-Observer Variability in an Intertidal Marine Citizen Science Experiment

Citizen science represents an effective means of collecting ecological data; however, the quality/reliability of these data is often questioned. Quality assurance procedures are therefore important to determine the validity of citizen science data and to promote confidence in conclusions. Here, data generated by a marine citizen science project conducted at 12 sites across the United Kingdom was used to investigate whether the use of a simple, low-taxonomic-resolution field-monitoring protocol allowed trained citizen scientists to generate data comparable to those of professional scientists. To do this, differences between field estimates of algal percentage cover generated by different observer units (i.e., trained citizen scientists, professional scientists, and combined units), and digitally derived baseline estimates were examined. The results show that in the field, citizen scientists generated data similar to those of professional scientists, demonstrating that training, coupled with the use of a simple, low-taxonomic-resolution protocol can allow citizen scientists to generate robust datasets in which variability likely represents ecological variation/change as opposed to observer variation. The results also show, irrespective of observer unit, that differences between field and digital baseline estimates of algal percentage cover were greatest in plots with medium levels of algal cover, highlighting that additional/enhanced training for all participants could be beneficial in this area. The approach presented can serve as a guide for existing and future projects with similar protocols to assess their data quality, to strengthen participant training/protocols, and ultimately to promote the incorporation of robust citizen science datasets into environmental research and management