An Investigation into the Impact of Social Networking on Knowledge Sharing

Today we are experiencing a rapidly increasing trend to use social networking in ways that dramatically affect both our personal and our public lives. This is a global phenomenon being experienced around the world. Exactly how this technology is being used and by whom is of great interest. The problem is that not a lot of research has been conducted to investigate the role social networking sites play to influence a person’s attitude toward sharing knowledge at work. In light of the marked increase in the use of social networking sites and how it is changing the way we live, both at work and during leisure activities, this research examines the factors that influence our attitudes towards knowledge sharing. This study presents the results of a quantitative research to understand the nature and impact of these motivating factors and analyzes how they influence our attitudes regarding the use of social networking sites as a venue in which to share knowledge. This study was conducted by means of an Internet survey. A self-administered questionnaire provided data and assisted in determining the degree to which the use of social networking sites is being used to share knowledge in the workplace. This non-experimental, cross-sectional, correlational study was conducted by means of quantitative research procedures to investigate the impact and influence social networking has on the knowledge transfer process. This research showed how social networking has redefined the collaborative environment that encourages knowledge holders to share their valuable knowledge. The results show that some factors, such as organizational climate, the subjective norm, and knowledge sharing attitudes, have a dominant impact on our behavior regarding the use of social networking sites and our intention to share knowledge with others. Another set of factors influenced our behavior and attitudes, but to a lesser degree, while one factor, anticipation of extrinsic rewards, actually exerted a negative influence on an individual’s knowledge sharing attitudes. The results of this dissertation increased and contributed to our understanding of the relationship between social networking sites and intention to share knowledge and set the stage for follow-on research

The Directional Dependence of the Lunar Cherenkov Technique for UHE Neutrino Detection

The LUNASKA (Lunar UHE Neutrino Astrophysics with the Square Kilometre Array) project is a theoretical and experimental project developing the lunar Cherenkov technique for the next generation of giant radio-telescope arrays. This contribution presents our simulation results on the directional dependence of the technique for UHE neutrino detection. In particular, these indicate that both the instantaneous sensitivities and time-integrated limits from lunar Cherenkov experiments such as those at Parkes, Goldstone, Kalyazin and ATCA are highly anisotropic. We study the regions of the sky which have not been probed by either these or other experiments, and present the expected sky coverage of future experiments with the SKA. Our results show how the sensitivity of Lunar Cherenkov observations to potential astrophysical sources of UHE particles may be maximised by choosing appropriate observations dates and antenna-beam pointing positions.Comment: 4 pages, 4 figures, presented at ARENA 2008, Rome, Ital

A prototype station for ARIANNA: a detector for cosmic neutrinos

The Antarctic Ross Iceshelf Antenna Neutrino Array (ARIANNA) is a proposed detector for ultra-high energy astrophysical neutrinos. It will detect coherent radio Cherenkov emission from the particle showers produced by neutrinos with energies above about 10^17 eV. ARIANNA will be built on the Ross Ice Shelf just off the coast of Antarctica, where it will eventually cover about 900 km^2 in surface area. There, the ice-water interface below the shelf reflects radio waves, giving ARIANNA sensitivity to downward going neutrinos and improving its sensitivity to horizontally incident neutrinos. ARIANNA detector stations will each contain 4-8 antennas which search for brief pulses of 50 MHz to 1 GHz radio emission from neutrino interactions. We describe a prototype station for ARIANNA which was deployed in Moore's Bay on the Ross Ice Shelf in December 2009, discuss the design and deployment, and present some initial figures on performance. The ice shelf thickness was measured to be 572 +/- 6 m at the deployment site.Comment: 15 pages with 5 figure

Radio Cherenkov signals from the Moon: neutrinos and cosmic rays

Neutrino production of radio Cherenkov signals in the Moon is the object of radio telescope observations. Depending on the energy range and detection parameters, the dominant contribution to the neutrino signal may come from interactions of the neutrino on the Moon facing the telescope, rather than neutrinos that have traversed a portion of the Moon. Using the approximate analytic expression of the effective lunar aperture from a recent paper by Gayley, Mutel and Jaeger, we evaluate the background from cosmic ray interactions in the lunar regolith. We also consider the modifications to the effective lunar aperture from generic non-standard model neutrino interactions. A background to neutrino signals are radio Cherenkov signals from cosmic ray interactions. For cosmogenic neutrino fluxes, neutrino signals will be difficult to observe because of low neutrino flux at the high energy end and large cosmic ray background in the lower energy range considered here. We show that lunar radio detection of neutrino interactions is best suited to constrain or measure neutrinos from astrophysical sources and probe non-standard neutrino-nucleon interactions such as microscopic black hole production.Comment: 16 pages, 19 figure

Limit on UHE Neutrino Flux from the Parkes Lunar Radio Cherenkov Experiment

The first search for ultra-high energy (UHE) neutrinos using a radio telescope was conducted by Hankins, Ekers and O'Sullivan (1996). This was a search for nanosecond duration radio Cherenkov pulses from electromagnetic cascades initiated by ultra-high energy (UHE) neutrino interactions in the lunar regolith, and was made using a broad-bandwidth receiver fitted to the Parkes radio telescope, Australia. At the time, no simulations were available to convert the null result into a neutrino flux limit. Since then, similar experiments at Goldstone, USA, and Kalyazin, Russia, have also recorded null results, and computer simulations have been used to model the experimental sensitivities of these two experiments and put useful limits on the UHE neutrino flux. Proposed future experiments include the use of broad-bandwidth receivers, making the sensitivity achieved by the Parkes experiment highly relevant to the future prospects of this field. We have therefore calculated the effective aperture for the Parkes experiment and found that when pointing at the lunar limb, the effective aperture at all neutrino energies was superior to single-antenna, narrow-bandwidth experiments, and that the detection threshold was comparable to that of the double-antenna experiment at Goldstone. However, because only a small fraction of the observing time was spent pointing the limb, the Parkes experiment places only comparatively weak limits on the UHE neutrino flux. Future efforts should use multiple telescopes and broad-bandwidth receivers.Comment: 6 pages, 2 figures, accepted for publication in MNRA

LUNASKA experiments using the Australia Telescope Compact Array to search for ultra-high energy neutrinos and develop technology for the lunar Cherenkov technique

We describe the design, performance, sensitivity and results of our recent experiments using the Australia Telescope Compact Array (ATCA) for lunar Cherenkov observations with a very wide (600 MHz) bandwidth and nanosecond timing, including a limit on an isotropic neutrino flux. We also make a first estimate of the effects of small-scale surface roughness on the effective experimental aperture, finding that contrary to expectations, such roughness will act to increase the detectability of near-surface events over the neutrino energy-range at which our experiment is most sensitive (though distortions to the time-domain pulse profile may make identification more difficult). The aim of our "Lunar UHE Neutrino Astrophysics using the Square Kilometer Array" (LUNASKA) project is to develop the lunar Cherenkov technique of using terrestrial radio telescope arrays for ultra-high energy (UHE) cosmic ray (CR) and neutrino detection, and in particular to prepare for using the Square Kilometer Array (SKA) and its path-finders such as the Australian SKA Pathfinder (ASKAP) and the Low Frequency Array (LOFAR) for lunar Cherenkov experiments.Comment: 27 pages, 18 figures, 4 tables

LUNASKA Experiment Observational Limits on UHE Neutrinos from Centaurus A and the Galactic Center

We present the first observational limits to the ultra-high energy (UHE) neutrino flux from the Galactic Center, and from Centaurus A which is the nearest active galactic nucleus (AGN). These results are based on our "Lunar UHE Neutrino Astrophysics using the Square Kilometer Array" (LUNASKA) project experiments at the Australia Telescope Compact Array (ATCA). We also derive limits for the previous experiments and compare these limits with expectations for acceleration and super-heavy dark matter models of the origin of UHE cosmic rays.Comment: 5 pages, 4 figures, additional experimental details and references given, limits now calculated also for NuMoon, uncertainties in calculation of LUNASKA limits now discussed, figures updated. Accepted for publication in MNRAS on 5 August 201

A Roadmap For Scientific Ballooning 2020-2030

From 2018 to 2020, the Scientific Balloon Roadmap Program Analysis Group (Balloon Roadmap PAG) served as an community-based, interdisciplinary forum for soliciting and coordinating community analysis and input in support of the NASA Scientific Balloon Program. The Balloon Roadmap PAG was tasked with articulating and prioritizing the key science drivers and needed capabilities of the Balloon Program for the next decade. Additionally, the Balloon Roadmap PAG was asked to evaluate the potential for achieving science goals and maturing technologies of the Science Mission Directorate, evaluate the Balloon Program goals towards community outreach, and asses commercial balloon launch opportunities. The culmination of this work has been a written report submitted to the NASA Astrophysics Division Director.Comment: 95 pages, 69 figures, prepared by the NASA Balloon Program Analysis Group for the NASA Astrophysics Division Director and the 2020 Astrophysics Decadal Surve