Focus group methodology in a life course approach – individual accounts within a peer cohort group

This paper explores the use of focus group methodology as part of a life course approach building on Julia Brannen’s pioneering work in these two areas. Much life course research uses individual interviews, including biographical interview techniques. It is less usual to find focus groups used within the life course perspective. This paper draws on a PhD study of young British and Asian adults’ experiences of the transition from university to full-time employment, using focus groups as part of a multi-method approach, within a life course perspective. The study drew explicitly on Julia Brannen’s approach to life course transitions. Three focus group excerpts are presented and discussed to illustrate how focus group data can further the understanding of the ways in which a group of peers discuss the transition to work and especially future work–life balance. We show how focus group discussions about individual choice for future work and ‘life’ or ‘lifestyle’ can highlight shared assumptions of this birth cohort group as well as areas of disagreement and contention, rooted in both individual experiences and societal and socio-cultural expectations. We relate this to Julia Brannen’s conceptualisation of the three different modalities which young people draw on to talk about the future

Heavy-Baryon Spectroscopy from Lattice QCD

We use a four-dimensional lattice calculation of the full-QCD (quantum chromodynamics, the non-abliean gauge theory of the strong interactions of quarks and gluons) path integrals needed to determine the masses of the charmed and bottom baryons. In the charm sector, our results are in good agreement with experiment within our systematics, except for the spin-1/2 $\Xi_{cc}$, for which we found the isospin-averaged mass to be $\Xi_{cc}$ to be $3665\pm17\pm14^{+0}_{-78}$ MeV. We predict the mass of the (isospin-averaged) spin-1/2 $\Omega_{cc}$ to be $3763\pm19\pm26^{+13}_{-79}$ {MeV}. In the bottom sector, our results are also in agreement with experimental observations and other lattice calculations within our statistical and systematic errors. In particular, we find the mass of the $\Omega_b$ to be consistent with the recent CDF measurement. We also predict the mass for the as yet unobserved $\Xi^\prime_b$ to be 5955(27) MeV.Comment: Invited talk at Conference of Computational Physics 2009. 3 page

Bottom baryons from a dynamical lattice QCD simulation

Bottom baryon masses are calculated based on a 2+1 flavor dynamical lattice QCD simulation. The gauge field configurations were computed by the CP-PACS and JLQCD collaborations using an improved clover action. The bottom quark is described using lattice NRQCD. Results are presented for single and double-b baryons at one lattice spacing. Comparison with experimental values is discussed.Comment: 8 pages, changes to references,revised calculation, new experimental results discussed, consistent with published versio

Air-Fuel Ratio Control of Spark Ignition Engines With Unknown System Dynamics Estimator: Theory and Experiments

This brief addresses the emission reduction of spark ignition engines by proposing a new control to regulate the air-fuel ratio (AFR) around the ideal value. After revisiting the engine dynamics, the AFR regulation is represented as a tracking control of the injected fuel amount. This allows to take the fuel film dynamics into consideration and simplify the control design. The lumped unknown engine dynamics in the new formulation are online estimated by suggesting a new effective unknown system dynamics estimator. The estimated variable can be superimposed on a commercially configured, well-calibrated gain scheduling like proportional-integral-differential (PID) control to achieve a better AFR response. The salient feature of this proposed control scheme lies in its simplicity and the small number of required measurements, that is, only the air mass flow rate, the pressure and temperature in the intake manifold, and the measured AFR value are used. Practical experiments on a Tata Motors Limited two-cylinder gasoline engine are carried out under a realistic driving cycle. The comparative results show that the proposed control can achieve an improved AFR control response and reduced emissions

Testing for Network and Spatial Autocorrelation

Testing for dependence has been a well-established component of spatial statistical analyses for decades. In particular, several popular test statistics have desirable properties for testing for the presence of spatial autocorrelation in continuous variables. In this paper we propose two contributions to the literature on tests for autocorrelation. First, we propose a new test for autocorrelation in categorical variables. While some methods currently exist for assessing spatial autocorrelation in categorical variables, the most popular method is unwieldy, somewhat ad hoc, and fails to provide grounds for a single omnibus test. Second, we discuss the importance of testing for autocorrelation in data sampled from the nodes of a network, motivated by social network applications. We demonstrate that our proposed statistic for categorical variables can both be used in the spatial and network setting

Focus group methodology in a life course approach – individual accounts within a peer cohort group

This paper explores the use of focus group methodology as part of a life course approach building on Julia Brannen’s pioneering work in these two areas. Much life course research uses individual interviews, including biographical interview techniques. It is less usual to find focus groups used within the life course perspective. This paper draws on a PhD study of young British and Asian adults’ experiences of the transition from university to full-time employment, using focus groups as part of a multi-method approach, within a life course perspective. The study drew explicitly on Julia Brannen’s approach to life course transitions. Three focus group excerpts are presented and discussed to illustrate how focus group data can further the understanding of the ways in which a group of peers discuss the transition to work and especially future work–life balance. We show how focus group discussions about individual choice for future work and ‘life’ or ‘lifestyle’ can highlight shared assumptions of this birth cohort group as well as areas of disagreement and contention, rooted in both individual experiences and societal and socio-cultural expectations. We relate this to Julia Brannen’s conceptualisation of the three different modalities which young people draw on to talk about the future