How to recognise a kick : A cognitive task analysis of drillers’ situation awareness during well operations

Acknowledgements This article is based on a doctoral research project of the first author which was sponsored by an international drilling rig operator. The views presented are those of the authors and should not be taken to represent the position or policy of the sponsor. The authors wish to thank the industrial supervisor and the drilling experts for their contribution and patience, as well as Aberdeen Drilling School for allowing the first author to attend one of their well control courses.Peer reviewedPostprin

Some aspects of fatigue crack propagation

Evaluation of fatigue crack propagation models on aluminum plates under load

It’s driving her mad: gender differences in the effects of commuting on psychological well-being

In this paper, we seek to explore the effects of commuting time on the psychological well-being of men and women in the UK. We use annual data from the British Household Panel Survey in a fixed effects panel framework that includes variables known to determine well-being, as well as factors which may provide compensation for commuting such as income, job satisfaction and housing quality. Our results show that, even after all these variables are considered, commuting still has an important detrimental effect on the well-being of women, but not men, and this result is robust to numerous different specifications. We explore possible explanations for this gender difference and can find no evidence that it is due to women´s shorter working hours or weaker occupational position. Rather women´s greater sensitivity to commuting time seems to be a result of their larger responsibility for day-to-day household tasks, including childcare

Digital simulation for post-docking response

The digital program, 2BODY, which simulates the translational and rotational motion of two connected rigid bodies and provides both digital and plot output is described. Relative rotation of the bodies at the connection is allowed, thereby providing a model suitable for studying system stability and response during a soft-dock regime. A users manual for the program is given as well as all the details and background pertaining to the equations of motion and mathematical models, integration scheme, and input/output routines

Two Trapping Systems to Determine Incidence and Duration of Migration of Adult Alfalfa Weevils, \u3ci\u3eHypera Postica\u3c/i\u3e (Coleoptera: Curculionidae)

Emergence and flight traps were used to study the pre- and post-diapause movements of the alfalfa weevil, Hypera postica. The emergence traps proved to be an excellent tool in determining the time of diapause termination and in providing an accurate accounting of the number of weevils per unit area in aestivation sites. The flight traps showed when diapause flights to and from alfalfa fields took place. Both trapping systems can be utilized in a pest control program to locate more closely where the alfalfa weevil aestivates and when diapause related movements occur

Fall Termination of Aestivation and Field Dispersal of the Alfalfa Weevil (Coleoptera: Curculionidae) in Illinois

Emergence traps, flight traps, sweeping, and egg sampling were employed to determine fall termination of aestivation of the alfalfa weevil, Hypera postica, and patterns and timing of field reentry, and subsequent fall oviposition. Adult alfalfa weevils were found to terminate aestivation in wood edge field borders in mid-late October. Field reentry began in late October as a gradual process, starting at wooded field borders, with the field population equally dispersed by mid-November

NASA/Pratt and Whitney experimental clean combustor program: Engine test results

A two-stage vorbix (vortex burning and mixing) combustor and associated fuel system components were successfully tested in an experimental JT9D engine at steady-state and transient operating conditions, using ASTM Jet-A fuel. Full-scale JT9D experimental engine tests were conducted in a phase three aircraft experimental clean combustor program. The low-pollution combustor, fuel system, and fuel control concepts were derived from phase one and phase two programs in which several combustor concepts were evaluated, refined, and optimized in a component test rig. Significant pollution reductions were achieved with the combustor which meets the performance, operating, and installation requirements of the engine

Digital data averager improves conventional measurement system performance

Multipurpose digital averager provides measurement improvement in noisy signal environments. It provides increased measurement accuracy and resolution to basic instrumentation devices by an arithmetical process in real time. It is used with standard conventional measurement equipment and digital data printers

Size rationalization and trade exposure in developing countries

Given the lack of direct evidence regarding industrial adjustment in response to trade liberalization, this paper tackles some very basic questions. Specifically, in LDCs, how is trade orientation correlated with the size distribution of plants and with plant-level labor productivity? It begins with a simple model that summarizes some effects of trade exposure on producer size and productive efficiency that have been stressed in the recent analytical and simulation literature. It then examines annual plant-level data from Chile and Colombia to determine whether these effects can be confirmed. The empirical results indicate that, over the long run, higher trade exposure is correlated with smaller plant sizes, controlling for industry and country effects. However, the mix of high versus low productivity plants is not strongly associated with trade exposure. Both of these findings cast doubt on the mechanisms linking trade, plant size, and productivity in a number of recent analytical and simulation studies.Economic Theory&Research,Environmental Economics&Policies,TF054105-DONOR FUNDED OPERATION ADMINISTRATION FEE INCOME AND EXPENSE ACCOUNT,Trade Policy,Science Education