University of Victoria

About: University of Victoria is a education organization based out in Victoria, British Columbia, Canada. It is known for research contribution in the topics: Population & Galaxy. The organization has 14994 authors who have published 41051 publications receiving 1447972 citations. The organization is also known as: Victoria College.

Open source software peer review practices: a case study of the apache server

Abstract: Peer review is seen as an important quality assurance mechanism in both industrial development and the open source software (OSS) community. The techniques for performing inspections have been well studied in industry; in OSS development, peer reviews are less well understood. We examine the two peer review techniques used by the successful, mature Apache server project: review-then-commit and commit-then-review. Using archival records of email discussion and version control repositories, we construct a series of metrics that produces measures similar to those used in traditional inspection experiments. Specifically, we measure the frequency of review, the level of participation in reviews, the size of the artifact under review, the calendar time to perform a review, and the number of reviews that find defects. We provide a comparison of the two Apache review techniques as well as a comparison of Apache review to inspection in an industrial project. We conclude that Apache reviews can be described as (1) early, frequent reviews (2) of small, independent, complete contributions (3) conducted asynchronously by a potentially large, but actually small, group of self-selected experts (4) leading to an efficient and effective peer review technique.

Projected impacts of climate change on marine fish and fisheries

Abstract: This paper reviews current literature on the projected effects of climate change on marine fish and shellfish, their fisheries, and fishery-dependent communities throughout the northern hemisphere. The review addresses the following issues: (i) expected impacts on ecosystem productivity and habitat quantity and quality; (ii) impacts of changes in production and habitat on marine fish and shellfish species including effects on the community species composition, spatial distributions, interactions, and vital rates of fish and shellfish; (iii) impacts on fisheries and their associated communities; (iv) implications for food security and associated changes; and (v) uncertainty and modelling skill assessment. Climate change will impact fish and shellfish, their fisheries, and fishery-dependent communities through a complex suite of linked processes. Integrated interdisciplinary research teams are forming in many regions to project these complex responses. National and international marine research organizations serve a key role in the coordination and integration of research to accelerate the production of projections of the effects of climate change on marine ecosystems and to move towards a future where relative impacts by region could be compared on a hemispheric or global level. Eight research foci were identified that will improve the projections of climate impacts on fish, fisheries, and fishery-dependent communities.

Combination of searches for invisible Higgs boson decays with the ATLAS experiment

Abstract: Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H→invisible decays where H is produced according to the standard model via vector boson fusion, Z(ll)H, and W/Z(had)H, all performed with the ATLAS detector using 36.1 fb^{-1} of pp collisions at a center-of-mass energy of sqrt[s]=13 TeV at the LHC. In combination with the results at sqrt[s]=7 and 8 TeV, an exclusion limit on the H→invisible branching ratio of 0.26(0.17_{-0.05}^{+0.07}) at 95% confidence level is observed (expected).

Photoevaporation of circumstellar disks around young stars.

Abstract: We examine the ability of photoevaporative disk winds to explain the low-velocity components observed in the forbidden line spectra of low-mass T Tauri stars. Using the analytic model of Shu and coworkers and Hollenbach and coworkers as a basis, we examine the characteristics of photoevaporative outflows with hydrodynamic simulations. General results from the simulations agree well with the analytic predictions, although some small differences are present. Most importantly, the flow of material from the disk surface develops at smaller radii than in the analytic approximations, and the flow velocity from the disk surface is only one-third the sound speed. A detailed presentation of observational consequences of the model is given, including predicted line widths, blueshifts, and integrated luminosities of observable sulfur and nitrogen emission lines. We demonstrate that these predictions are in agreement with current observational data on the low-velocity forbidden line emission of ionized species from T Tauri stars. This is in contrast to magnetic wind models, which systematically underpredict these forbidden line luminosities. However, the present model cannot easily account for the luminosities of neutral oxygen lines in T Tauri stars.

Weakening of the subduction interface and its effects on surface heat flow, slab dehydration, and mantle wedge serpentinization

Abstract: [1] The shallow part of the interface between the subducting slab and the overriding mantle wedge is evidently weakened by the presence of hydrous minerals and high fluid pressure. We use a two-dimensional finite element model, with a thin layer of uniform viscosity along the slab surface to represent the strength of the interface and a dislocation-creep rheology for the mantle wedge, to investigate the effect of this interface “decoupling.” Decoupling occurs when the temperature-dependent viscous strength of the mantle wedge is greater than that of the interface layer. We find that the maximum depth of decoupling is the key to most primary thermal and petrological processes in subduction zone forearcs. The forearc mantle wedge above a weakened subduction interface always becomes stagnant (<0.2% slab velocity), providing a stable thermal environment for the formation of serpentinite. The degree of mantle wedge serpentinization depends on the availability of aqueous fluids from slab dehydration. A very young and warm slab releases most of its bound H2O in the forearc, leading to a high degree of mantle wedge serpentinization. A very old and cold slab retains most of its H2O until farther landward, leading to a lower degree of serpentinization. Our preferred model for northern Cascadia has a maximum decoupling depth of about 70–80 km, which provides a good fit to surface heat flow data, predicts conditions for a high degree of serpentinization of the forearc mantle wedge, and is consistent with the observed shallow intraslab seismicity and low volume of arc volcanism.