14,563 research outputs found
Twenty-three women officers’ experiences of policing in England: The same old story or a different story?
Our research project was concerned primarily with using a feminist analysis to explore the lived reality of 23 women police officers in England and Wales. We undertook 23 qualitative interviews with our participants and our research straddles four decades of policing practice, which allowed us to explore changes that were seen to have taken place during this period. First, participants discussed their lived reality, which included banter, bullying and harassment for many. Second, and perhaps more surprisingly, at certain times of unrest, riots or threats, some of our participants were provided with opportunities, for example, during the IRA threat, the riot in Toxteth and the miners’ strike. We suggest that examples from our data capture an early disruption of the ‘ideal’ heroic male police officer that Silvestri examines [Silvestri M (2018) Disrupting the ‘heroic’ male within policing: a case of direct entry. Feminist Criminology 13(3): 309–328] whose removal from their normal role during periods of socio-political disorder allowed women officers to leave the gendered division of labour and undertake the heroic police constable role while the men were busy being ‘heroic’ at the source of threat and unrest. We sought to explore changes such as the uniform as a site of protest for some of our officers who challenged an uncomfortable and unfit uniform in the early days, and explained that there were still problems with the kit and design at times. Our findings illustrated that, on the whole, although massive changes had been made, it was a case of the same old story in terms of sexual harassment and banter for female officers and more was required to address these issues, which fits with reviews and studies in both England and Wales and in Australia. Finally, we noted using participants’ words how much many of these women had enjoyed their role within policing in spite of these challenges
Shallow grooves in journal improve air bearing performance
Bearing designs, which shape the surface to create artificial fluid-film wedges in the absence of any applied radial load, generate radial restoring forces to keep journals from whirling. Helical- or herringbone-grooved journals or rotors show most promise of stable operation, with no sacrifice in load capacity
Experimental dynamic stiffness and damping of externally pressurized gas-lubricated journal bearings
A rigid vertical shaft was operated with known amounts of unbalance at speeds to 30,000 rpm and gas supply pressure ratios to 4.8. From measured amplitude and phase angle data, dynamic stiffness and damping coefficients of the bearings were determined. The measured stiffness was proportional to the supply pressure, while damping was little affected by supply pressure. Damping dropped rapidly as the fractional frequency whirl threshold was approached. A small-eccentricity analysis overpredicted the stiffness by 20 to 70 percent. Predicted damping was lower than measured at low speeds but higher at high speeds
Experiments on rotating externally pressurized air journal bearings. Part 2 - Attitude angle and air flow
Air flow and attitude angle compared with theory for rotating externally pressurized air journal bearing
Reparameterizing the Birkhoff Polytope for Variational Permutation Inference
Many matching, tracking, sorting, and ranking problems require probabilistic
reasoning about possible permutations, a set that grows factorially with
dimension. Combinatorial optimization algorithms may enable efficient point
estimation, but fully Bayesian inference poses a severe challenge in this
high-dimensional, discrete space. To surmount this challenge, we start with the
usual step of relaxing a discrete set (here, of permutation matrices) to its
convex hull, which here is the Birkhoff polytope: the set of all
doubly-stochastic matrices. We then introduce two novel transformations: first,
an invertible and differentiable stick-breaking procedure that maps
unconstrained space to the Birkhoff polytope; second, a map that rounds points
toward the vertices of the polytope. Both transformations include a temperature
parameter that, in the limit, concentrates the densities on permutation
matrices. We then exploit these transformations and reparameterization
gradients to introduce variational inference over permutation matrices, and we
demonstrate its utility in a series of experiments
A view of Large Magellanic Cloud HII regions N159, N132, and N166 through the 345 GHz window
We present results obtained towards the HII regions N159, N166, and N132 from
the emission of several molecular lines in the 345 GHz window. Using ASTE we
mapped a 2.4' 2.4' region towards the molecular cloud N159-W in the
CO J=3-2 line and observed several molecular lines at an IR peak very
close to a massive young stellar object. CO and CO J=3-2 were
observed towards two positions in N166 and one position in N132. The CO
J=3-2 map of the N159-W cloud shows that the molecular peak is shifted
southwest compared to the peak of the IR emission. Towards the IR peak we
detected emission from HCN, HNC, HCO, CH J=4-3, CS J=7-6, and
tentatively CO J=3-2. This is the first reported detection of these
molecular lines in N159-W. The analysis of the CH line yields more
evidence supporting that the chemistry involving this molecular species in
compact and/or UCHII regions in the LMC should be similar to that in Galactic
ones. A non-LTE study of the CO emission suggests the presence of both cool and
warm gas in the analysed region. The same analysis for the CS, HCO, HCN,
and HNC shows that it is very likely that their emissions arise mainly from
warm gas with a density between to some cm. The
obtained HCN/HNC abundance ratio greater than 1 is compatible with warm gas and
with an star-forming scenario. From the analysis of the molecular lines
observed towards N132 and N166 we propose that both regions should have similar
physical conditions, with densities of about 10 cm.Comment: accepted in MNRAS (October 5, 2015
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