Analysis of the temperature influence on Langmuir probe measurements on the basis of gyrofluid simulations

The influence of the temperature and its fluctuations on the ion saturation current and the floating potential, which are typical quantities measured by Langmuir probes in the turbulent edge region of fusion plasmas, is analysed by global nonlinear gyrofluid simulations for two exemplary parameter regimes. The numerical simulation facilitates a direct access to densities, temperatures and the plasma potential at different radial positions around the separatrix. This allows a comparison between raw data and the calculated ion saturation current and floating potential within the simulation. Calculations of the fluctuation-induced radial particle flux and its statistical properties reveal significant differences to the actual values at all radial positions of the simulation domain, if the floating potential and the temperature averaged density inferred from the ion saturation current is used.Comment: Submitted to Plasma Physics and Controlled Fusio

Mind the Gap: DBA students, knowledge generation, transfer and impact

Increasingly higher education institutions are expected to demonstrate their contribution to academia, society, and the economy. This is pertinent for business schools as a key purpose for them is to provide education that enhances management practice, with Doctorates in Business Administration (DBAs) being the highest-level qualification offered in pursuit of this goal. Yet there is scant research that captures the impact of DBAs beyond the individual and academia. This paper focuses on the important role of DBAs in generating and transferring knowledge from academia to practice and in creating wider impact in society and the economy. Based on 36 semi-structured interviews with DBA students and alumni, our research shows how DBA students are able to generate and exchange knowledge between academia and business, enabling a wide range of impacts to be achieved. We show how knowledge transfer is the outcome of a learning process in which DBA students and their supervisors learn to speak each other’s language, enabling two-way communication. Facilitated by the power and associated credibility and legitimacy of the DBA students as practicing senior managers, the knowledge can then be transferred. Personal development in the form of analytical skills and increased confidence gained through the learning process results in a personal impact that acts as the precursor to other forms of impact, such as improved organisational performance and broader societal benefits. Research generated by DBAs is thus well-placed to offer opportunities for impact and contribute substantially to the research-practice conversation in higher education

Targeting Mr Average: Participation, gender equity and school sport partnerships

The School Sport Partnership Programme (SSPP) is one strand of the national strategy for physical education and school sport in England, the physical education and school sport Club Links Strategy (PESSCL). The SSPP aims to make links between school physical education (PE) and out of school sports participation, and has a particular remit to raise the participation levels of several identified under-represented groups, of which girls and young women are one. National evaluations of the SSPP show that it is beginning to have positive impacts on young people's activity levels by increasing the range and provision of extra curricular activities (Office for Standards in Education (OFSTED), 2003, 2004, 2005; Loughborough Partnership, 2005, 2006). This paper contributes to the developing picture of the phased implementation of the programme by providing qualitative insights into the work of one school sport partnership with a particular focus on gender equity. The paper explores the ways in which gender equity issues have been explicitly addressed within the 'official texts' of the SSPP; how these have shifted over time and how teachers are responding to and making sense of these in their daily practice. Using participation observation, interview and questionnaire data, the paper explores how the coordinators are addressing the challenge of increasing the participation of girls and young women. The paper draws on Walby's (2000) conceptualisation of different kinds of feminist praxis to highlight the limitations of the coordinators' work. Two key themes from the data and their implications are addressed: the dominance of competitive sport practices and the PE professionals' views of targeting as a strategy for increasing the participation of under-represented groups. The paper concludes that coordinators work within an equality or difference discourse with little evidence of the transformative praxis needed for the programme to be truly inclusive. © 2008 Taylor & Francis

A Structural Analysis of Star-Forming Region AFGL 490

We present Spitzer IRAC and MIPS observations of the star-forming region containing intermediate-mass young stellar object (YSO) AFGL 490. We supplement these data with near-IR 2MASS photometry and with deep SQIID observations off the central high extinction region. We have more than doubled the known membership of this region to 57 Class I and 303 Class II YSOs via the combined 1-24 um photometric catalog derived from these data. We construct and analyze the minimum spanning tree of their projected positions, isolating one locally over-dense cluster core containing 219 YSOs (60.8% of the region's members). We find this cluster core to be larger yet less dense than similarly analyzed clusters. Although the structure of this cluster core appears irregular, we demonstrate that the parsec-scale surface densities of both YSOs and gas are correlated with a power law slope of 2.8, as found for other similarly analyzed nearby molecular clouds. We also explore the mass segregation implications of AFGL 490's offset from the center of its core, finding that it has no apparent preferential central position relative to the low-mass members.Comment: 44 pages, 13 figures, accepted to Ap

Evidence for nonlinear diffusive shock acceleration of cosmic-rays in the 2006 outburst of the recurrent nova RS Ophiuchi

Spectroscopic observations of the 2006 outburst of the recurrent nova RS Ophiuchi at both infrared (IR) and X-ray wavelengths have shown that the blast wave has decelerated at a higher rate than predicted by the standard test-particle adiabatic shock-wave model. Here we show that the observed evolution of the nova remnant can be explained by the diffusive shock acceleration of particles at the blast wave and the subsequent escape of the highest energy ions from the shock region. Nonlinear particle acceleration can also account for the difference of shock velocities deduced from the IR and X-ray data. The maximum energy that accelerated electrons and protons can have achieved in few days after outburst is found to be as high as a few TeV. Using the semi-analytic model of nonlinear diffusive shock acceleration developed by Berezhko & Ellison, we show that the postshock temperature of the shocked gas measured with RXTE/PCA and Swift/XRT imply a relatively moderate acceleration efficiency.Comment: Accepted for publication in ApJ

Investigating the Role of Information Technology in Building Buyer-Supplier Relationships

A widely held position observed through the lens of transaction cost theory (TCT) has been the role of information technology in decreasing transaction costs between buyers and suppliers and in creating more market based governance structures. However, observations have not supported this contention. In particular, buyer-supplier dyads often engage in cooperative behavior that could offset opportunistic tendencies espoused by TCT. The role of IT in this structure is unclear. This paper examines the relationship between perceived transaction costs and the concept of relationalism within buyer-supplier dyads. The role of IT in mediating this relationship is also examined. Survey data from 203 buyers in the OEM electronics industry is used to test proposed hypotheses. All major constructs, transaction costs, relationalism, and IT use are operationalized using validated multidimensional scales. The results suggest a positive role of IT in partially offsetting the negative relationship between transaction costs and relationalism. The results suggest that the decision to use IT within the dyad can encourage a commitment to establishing relational behavior

Mathematical Modeling of the Diffusion of Water in Wood During Drying

The drying of lumber was modeled by the diffusion of water in wood, according to Fick's second law. In the model the following assumptions were made: (1) Moisture content is the driving force; (2) the diffusion coefficient is a constant value above the fiber saturation point and one-fourth that value below the fiber saturation point; (3) equilibrium exists between the moisture content at the wood surface and the film of air adjacent to the surface; (4) moisture movement from the film to the bulk air stream occurs by film mass transfer. Five independent variables—half thickness of the board, species factor (density-diffusivity), temperature, relative humidity, and air velocity—were found to influence the drying process. This study reveals that variable interactions are important considerations when one wishes to predict drying times.Using red oak and constant values for lumber thickness and kiln air velocity, three cases were modeled to illustrate the potential for improved operation. The first case follows temperature and humidity schedules typical of current kiln operations, forming a basis for comparison. In the second case, a solar-powered kiln produces harmonic variations in temperature and relative humidity. The most favorable drying conditions occur in the late afternoon, the least favorable before dawn. Slower drying with nightly relaxation of the moisture profile may produce a board with few defects. In the final study, temperature and maximum permissible drying rate are specified, with relative humidity chosen according to the model. This case produced the most rapid drying, yet has milder moisture gradients than the base case. The results of these studies show the possibility of producing a high-quality product at low cost in a solar-powered dryer, or optimizing drying schedules to reduce drying time and increase product quality