37 research outputs found
Why Do Developers Get Password Storage Wrong? A Qualitative Usability Study
Passwords are still a mainstay of various security systems, as well as the
cause of many usability issues. For end-users, many of these issues have been
studied extensively, highlighting problems and informing design decisions for
better policies and motivating research into alternatives. However, end-users
are not the only ones who have usability problems with passwords! Developers
who are tasked with writing the code by which passwords are stored must do so
securely. Yet history has shown that this complex task often fails due to human
error with catastrophic results. While an end-user who selects a bad password
can have dire consequences, the consequences of a developer who forgets to hash
and salt a password database can lead to far larger problems. In this paper we
present a first qualitative usability study with 20 computer science students
to discover how developers deal with password storage and to inform research
into aiding developers in the creation of secure password systems
Moving to an Earnings-Related Parental Leave System Do Heterogeneous Effects on Parents Make Some Children Worse Off?
Can moving to an earnings-related parental leave system influence children s well-being and are heterogeneous effects on parents carried over to the entire family, making special groups of children worse off than others? To answer this question, this study exploits a large and unanticipated parental leave reform in Germany as a natural experiment. By replacing a means-tested by an earnings-related system the reform affected different groups of families to a variable extent. I find significant negative effects on newborns personality, while 2-3-year-old children improve their basic life skills and language skills. The first effect is especially pronounced in families who would be subject to a non-positive change in the overall benefit amount compared to the pre-reform situation, the second one is rather driven by those coming out as the reform s winners
Nature documentaries as catalysts for change: Mapping out the 'Blackfish Effect'
It is essential for us to understand what drives human behaviour if we want to tackle anthropogenic damage to the environment. Popular media can play an important role in shaping public attitudes, behaviours and norms towards wildlife, and documentaries in particular have become an increasingly prominent tool for social change. There is, however, a need for robust impact evaluation both in documentary-making and in conservation, to refine future interventions. The 2013 documentary Blackfish portrayed human–orca interactions at the US-based marine park, SeaWorld. Following its release, SeaWorld suffered financial difficulties and the company underwent structural changes, including a cessation of its orca breeding programme. These impacts have often been attributed to the Blackfish documentary, but little evidence has been provided to justify these claims. We combined an analysis of stock market data and semi-structured interviews with 26 key informants to build an in-depth contribution analysis. We used General Elimination Methodology, a qualitative impact evaluation methodology to build an understanding of the impact of Blackfish. We found a consensus among stakeholder groups that Blackfish induced negative publicity for SeaWorld and a change in people's perceptions of captivity. As a result, attendance at the park decreased and the market value of the company dropped. Blackfish catalysed a whole movement against marine mammal captivity. There were three key factors that led to its impact: the support from major distribution channels which allowed it to reach major audiences, emotional impact of the content and timing of its release. Blackfish benefitted from a perfect storm, building upon decades of activism to create an appropriate cultural climate for its release in 2013
Additive Manufacturing via Tube Extrusion (AMTEx)
Large scale Fused Filament Fabrication (FFF) is a growing area of interest within AM, with several unresolved problems: the volumetric cost of materials is high, the printing process is slow and low cooling rates result in unstable or sagging structures. This paper presents the concept of additive manufacturing via tube extrusion (AMTEx) as a means of overcoming these issues.
Using hollow tubes in place of solid extrusions means material use is reduced and cooling properties are vastly improved, allowing spans in excess of 400 mm without sag. Conventional freeform extrusion relies on the use of six-axis robots to orientate the extruder nozzle tangentially to the toolpath. It was found that slight pressurisation of the inside of printed tubes allowed extrusion at more than 90° from the nozzle axis without tube collapse. Aside from reducing the possibility of robot-print collisions, this also allows the use of traditional 3D printing slicing software to generate printer toolpaths. It also opens the potential to use conventional three-axis machines, greatly increasing the applicability of printing with tubes. AMTEx tubes were found to be stronger under tension and bending compared to equivalent FFF parts and had significantly improved ductility