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Tunability of the partially ordered double perovskite (PODP) and coexisting spin-glass phase in SrMn1-xWxO3 (x=0.20 to 0.40) have been studied using neutron powder diffraction (NPD), muon spin relaxation (MuSR), and magnetic susceptibility (X) measurements. Structural studies reveal that SrMn1-xWxO3 undergoes a quasi-continuous transformation from simple perovskite (Pm-3m) to PODP (P21/n) phase as x increases. Xdc(T) and Xac(T) measurements show a sharp cusp-like peak at a spin glass transition, Tg. The muon relaxation rate ({\lambda}) peaks at Tg following a critical growth, given by {\lambda}={\lambda}(0).t-w [t=(T-Tg)/Tg]. However, no long-range magnetic order is observed in NPD below Tg. These measurements confirm a tunable spin-glass freezing in SrMn1-xWxO3 with Tg monotonously decreasing with W content, which we attribute to tuning the relative concentration of the coexisting Mn-O-Mn and Mn-O-W-O-Mn anti-ferromagnetic super-exchange pathways altering the geometric frustration.

Volunteer computing (VC) or distributed computing projects are common in the citizen cyberscience (CCS) community and present extensive opportunities for scientists to make use of computing power donated by volunteers to undertake large-scale scientific computing tasks. Volunteer computing is generally a non-interactive process for those contributing computing resources to a project whereas volunteer thinking (VT) or distributed thinking, which allows volunteers to participate interactively in citizen cyberscience projects to solve human computation tasks. In this paper we describe the integration of three tools, the Virtual Atom Smasher (VAS) game developed by CERN, LiveQ, a job distribution middleware, and CitizenGrid, an online platform for hosting and providing computation to CCS projects. This integration demonstrates the combining of volunteer computing and volunteer thinking to help address the scientific and educational goals of games like VAS. The paper introduces the three tools and provides details of the integration process along with further potential usage scenarios for the resulting platform., Comment: 12 pages, 13 figures

In the last few years, contributions of the general public in scientific projects has increased due to the advancement of communication and computing technologies. Internet played an important role in connecting scientists and volunteers who are interested in participating in their scientific projects. However, despite potential benefits, only a limited number of crowdsourcing based large-scale science (citizen science) projects have been deployed due to the complexity involved in setting them up and running them. In this paper, we present CitizenGrid - an online middleware platform which addresses security and deployment complexity issues by making use of cloud computing and virtualisation technologies. CitizenGrid incentivises scientists to make their small-to-medium scale applications available as citizen science projects by: 1) providing a directory of projects through a web-based portal that makes applications easy to discover; 2) providing flexibility to participate in, monitor, and control multiple citizen science projects from a common interface; 3) supporting diverse categories of citizen science projects. The paper describes the design, development and evaluation of CitizenGrid and its use cases., Comment: 11 pages

In recent years, the networks of low-power devices have gained popularity. Typically these devices are wireless and interact to form large networks such as the Machine to Machine (M2M) networks, Internet of Things (IoT), Wearable Computing, and Wireless Sensor Networks. The collaboration among these devices is a key to achieving the full potential of these networks. A major problem in this field is to guarantee robust communication between elements while keeping the whole network energy efficient. In this paper, we introduce an extended and improved emergent broadcast slot (EBS) scheme, which facilitates collaboration for robust communication and is energy efficient. In the EBS, nodes communication unit remains in sleeping mode and are awake just to communicate. The EBS scheme is fully decentralized, that is, nodes coordinate their wake-up window in partially overlapped manner within each duty-cycle to avoid message collisions. We show the theoretical convergence behavior of the scheme, which is confirmed through real test-bed experimentation., Comment: 12 Pages, 11 Figures, Journal

In recent years, citizen science has grown in popularity due to a number of reasons, including the emphasis on informal learning and creativity potential associated with these initiatives. Citizen science projects address research questions from various domains, ranging from Ecology to Astronomy. Due to the advancement of communication technologies, which makes outreach and engagement of wider communities easier, scientists are keen to turn their own research into citizen science projects. However, the development, deployment and management of these projects remains challenging. One of the most important challenges is building the project itself. There is no single tool or framework, which guides the step-by-step development of the project, since every project has specific characteristics, such as geographical constraints or volunteers' mode of participation. Therefore, in this article, we present a series of conceptual frameworks for categorisation, decision and deployment, which guide a citizen science project creator in every step of creating a new project starting from the research question to project deployment. The frameworks are designed with consideration to the properties of already existing citizen science projects and could be easily extended to include other dimensions, which are not currently perceived.