Is It Safe to Uplift This Patch? An Empirical Study on Mozilla Firefox

In rapid release development processes, patches that fix critical issues, or implement high-value features are often promoted directly from the development channel to a stabilization channel, potentially skipping one or more stabilization channels. This practice is called patch uplift. Patch uplift is risky, because patches that are rushed through the stabilization phase can end up introducing regressions in the code. This paper examines patch uplift operations at Mozilla, with the aim to identify the characteristics of uplifted patches that introduce regressions. Through statistical and manual analyses, we quantitatively and qualitatively investigate the reasons behind patch uplift decisions and the characteristics of uplifted patches that introduced regressions. Additionally, we interviewed three Mozilla release managers to understand organizational factors that affect patch uplift decisions and outcomes. Results show that most patches are uplifted because of a wrong functionality or a crash. Uplifted patches that lead to faults tend to have larger patch size, and most of the faults are due to semantic or memory errors in the patches. Also, release managers are more inclined to accept patch uplift requests that concern certain specific components, and-or that are submitted by certain specific developers.Comment: In proceedings of the 33rd International Conference on Software Maintenance and Evolution (ICSME 2017

Future chlorine-bromine loading and ozone depletion

The prediction of future ozone requires three elements: (1) a scenario for the net emissions of chemically and radiatively active trace gases from the land and oceans; (2) a global atmospheric model that projects the accumulation of these gases; and (3) a chemical transport model that describes the distribution of ozone for a prescribed atmospheric composition and climate. This chapter, of necessity, presents models for all three elements and focuses on the following: (1) atmospheric abundance of chlorine and bromine in the form of halocarbons; and (2) the associated perturbations to stratospheric ozone

The Impact of Digital Platform Rapid Release Strategy on App Update Behavior: An Empirical Study of Firefox

The success of platform-based software ecosystems depends on the crucial coordination between the platform and third-party applications during co-evolution. Leveraging the change of platform release governance of Firefox, this paper examines the impact of the rapid release process on app update behavior (app responsiveness and app size change). Drawing on boundary resource perspective, we theorize how rapid release process as a social boundary resource affects app update behavior, and how app developers’ usage of technical boundary resource (i.e. platform API) affects this impact. Using a unique longitudinal dataset in Firefox, we conduct empirical analyses and conclude that the rapid release process decreases size change of app updates while platform API usage enhances app responsiveness. Moreover, platform API usage strengthens the effects of the rapid release process on app update behavior. This research enhances our understanding of the impact of platform governance practices on platform-third party coordination and provides practical guidance. Keywords: Platform-based software ecosystem, platform governance, app update, Rapid Release, boundary resourc

Advanced power sources for space missions

Approaches to satisfying the power requirements of space-based Strategic Defense Initiative (SDI) missions are studied. The power requirements for non-SDI military space missions and for civil space missions of the National Aeronautics and Space Administration (NASA) are also considered. The more demanding SDI power requirements appear to encompass many, if not all, of the power requirements for those missions. Study results indicate that practical fulfillment of SDI requirements will necessitate substantial advances in the state of the art of power technology. SDI goals include the capability to operate space-based beam weapons, sometimes referred to as directed-energy weapons. Such weapons pose unprecedented power requirements, both during preparation for battle and during battle conditions. The power regimes for these two sets of applications are referred to as alert mode and burst mode, respectively. Alert-mode power requirements are presently stated to range from about 100 kW to a few megawatts for cumulative durations of about a year or more. Burst-mode power requirements are roughly estimated to range from tens to hundreds of megawatts for durations of a few hundred to a few thousand seconds. There are two likely energy sources, chemical and nuclear, for powering SDI directed-energy weapons during the alert and burst modes. The choice between chemical and nuclear space power systems depends in large part on the total duration during which power must be provided. Complete study findings, conclusions, and eight recommendations are reported

The Impact of Monetary Union and the Euro on European Capital Markets: What May Be Achieved in Capital Market Integration

Up to now, the Euro has been successful in replacing the traditional European currencies and in altering the landscape of European Capital Markets. Domestic users of the Euro are almost the same in number as the population of the United STates, although the Gross Domestic Products of the two economies are clearly not comparable. Still, if the Member States within the Euro-area truly want to be recognized as an integrated capital market, some work must be done. This Article will estimate, from current economic thought, what remains to be done and what can be achieved in the short term. Some historical analysis will help in identifying the players and the main trends at work. Moreover, some of the international issues that have been raised by the new role of the European Monetary Union (“EMU”) will be presented