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Where's the harm? A social marketing approach to reframing 'problem' drinking cultures
Alcohol consumption is often linked to a broad range of social and health problems, yet alcohol also plays a fundamental role in social bonding between people. This paper considers the potential of social marketing to contribute to alcohol consumption reduction and reframe social norms that encourage 'problem' drinking. Based on qualitative research with a variety of Scottish drinkers, the paper emphasises how and why a better understanding of the culturally bound meanings of alcohol (e.g. social identity, self-concept) are of crucial importance to inform any social marketing approach to reframing excessive drinking
Very-high-energy gamma radiation from supernova remnants as seen with H.E.S.S
Very-high-energy (VHE, E > 100 GeV) gamma radiation has already been detected
from several supernova remnants (SNRs). These objects, which are well-studied
in radio, optical and X-ray wavelengths, constitute one of the most intriguing
source classes in VHE astronomy. H.E.S.S., an array of four imaging atmospheric
Cherenkov telescopes in Namibia, has recorded an extensive dataset of VHE
gamma-ray observations covering the central region of the Milky Way, both from
pointed observations as well as from the Galactic Plane Survey conducted in the
inner region of the Galaxy. From radio observations, several hundred SNRs are
known in the Milky Way, but until now only few of them have been identified as
VHE gamma-ray emitters. Using the H.E.S.S. dataset and a large ensemble of
radio SNRs localized in the inner region of the Galaxy, the standard framework
that links the origin of cosmic rays to the gamma-ray visibility of SNRs can
now be tested. Here we present the ensemble of investigated SNRs and discuss
constraints on the parameter space used within a theoretical model of hadronic
VHE gamma-ray production.Comment: Proceeding of the 32nd ICRC, August 11-18 2011, Beijing, Chin
SQG-Differential Evolution for difficult optimization problems under a tight function evaluation budget
In the context of industrial engineering, it is important to integrate
efficient computational optimization methods in the product development
process. Some of the most challenging simulation-based engineering design
optimization problems are characterized by: a large number of design variables,
the absence of analytical gradients, highly non-linear objectives and a limited
function evaluation budget. Although a huge variety of different optimization
algorithms is available, the development and selection of efficient algorithms
for problems with these industrial relevant characteristics, remains a
challenge. In this communication, a hybrid variant of Differential Evolution
(DE) is introduced which combines aspects of Stochastic Quasi-Gradient (SQG)
methods within the framework of DE, in order to improve optimization efficiency
on problems with the previously mentioned characteristics. The performance of
the resulting derivative-free algorithm is compared with other state-of-the-art
DE variants on 25 commonly used benchmark functions, under tight function
evaluation budget constraints of 1000 evaluations. The experimental results
indicate that the new algorithm performs excellent on the 'difficult' (high
dimensional, multi-modal, inseparable) test functions. The operations used in
the proposed mutation scheme, are computationally inexpensive, and can be
easily implemented in existing differential evolution variants or other
population-based optimization algorithms by a few lines of program code as an
non-invasive optional setting. Besides the applicability of the presented
algorithm by itself, the described concepts can serve as a useful and
interesting addition to the algorithmic operators in the frameworks of
heuristics and evolutionary optimization and computing
Fostering sustainability through technology-mediated interactions: Conviviality and reciprocity in the sharing economy
Purpose: This article addresses the lack of scholarly attention paid to the sharing economy from a sociological perspective, with respect to the technology-mediated interactions between sharing economy users. The paper provides a critical overview of the sharing economy and its impact on business and communities and explores how information technology can facilitate authentic, genuine sharing, through exercising and enabling conviviality and non-direct reciprocity. Approach: The paper begins with a critique of the technology-mediated sharing economy; introduces the concept of conviviality as a tool to grow and shape community and sustainability within the sharing economy; then explores reciprocity and sharing behaviour. Finally, the paper draws upon social exchange theory to illustrate conviviality and reciprocity, using four case studies of technology-enabled sharing. Findings: The paper contributes to the emerging debate around how the sharing economy, driven by information systems and technology affects social cohesion and personal relationships. The paper elucidates the central role conviviality and reciprocity play in explaining the paradoxes, tensions and impact of the sharing economy on society. Conviviality and reciprocity are positioned as key capabilities of a more sustainable version of the sharing economy, enabled via information technology. Originality and value: The findings reveal that information technology mediated sharing enterprises should promote conviviality and reciprocity in order to deliver more positive environmental, economic and social benefits. The diversity of existing operations indicated by he findings and the controversies discussed will guide the critical study of the social potential of sharing economy to avoid treating all sharing alike
Never the twain shall meet: a critical appraisal of the combination of discourse and psychoanalytic theory in studies of men and masculinity
In recent years there has been a number of attempts by different researchers to study men and masculinity using a combination of discourse theory and psychoanalysis. The main reason for this development is the sense that, on its own, discourse theory provides an incomplete account of masculine subjectivity. Psychoanalysis is thought to be able to fill those gaps. In this paper I want to begin by reviewing these arguments. I will provide an outline of the alleged deficiencies in discursive approaches to men and masculinity before going on to examine some of the work that has attempted the above synthesis. What I aim to show is that, for a number of reasons, such attempts are bound to fail. Instead, I will argue that better progress can be made in studies of masculinity by remaining within the theoretical boundaries of Discursive Psychology
Exoplanets and SETI
The discovery of exoplanets has both focused and expanded the search for
extraterrestrial intelligence. The consideration of Earth as an exoplanet, the
knowledge of the orbital parameters of individual exoplanets, and our new
understanding of the prevalence of exoplanets throughout the galaxy have all
altered the search strategies of communication SETI efforts, by inspiring new
"Schelling points" (i.e. optimal search strategies for beacons). Future efforts
to characterize individual planets photometrically and spectroscopically, with
imaging and via transit, will also allow for searches for a variety of
technosignatures on their surfaces, in their atmospheres, and in orbit around
them. In the near-term, searches for new planetary systems might even turn up
free-floating megastructures.Comment: 9 page invited review. v2 adds some references and v3 has other minor
additions and modification
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