Conventional, straight keyboards remain the most popular design among keyboards sold and used with personal computers despite the biomechanical benefits offered by alternative keyboard designs. Some typists indicate that the daunting medical device-like appearance of these alternative 'ergonomic' keyboards is the reason for not purchasing an alternative keyboard design. The purpose of this research was to create a new computer keyboard that promoted more neutral postures in the wrist while maintaining the approachability and typing performance of a straight keyboard. The design process created a curved alphanumeric keyboard, designed to reduce ulnar deviation, and a built-in, padded wrist-rest to reduce wrist extension. Typing performance, wrist postures and perceptions of fatigue when using the new curved keyboard were compared to those when using a straight keyboard design. The curved keyboard reduced ulnar deviation by 2.2 degrees +/- 0.7 (p< 0.01). Relative to the straight keyboard without a built-in wrist-rest, the prototype curved keyboard with the built-in padded wrist-rest reduced wrist extension by 6.3 degrees +/- 1.2 (p < 0.01). There were no differences in typing speed or accuracy between keyboards. Perceived fatigue ratings were significantly lower in the hands, forearms and shoulders with the curved keyboard. The new curved keyboard achieved its design goal of reducing discomfort and promoting more neutral wrist postures while not compromising users' preferences and typing performance.

BNFL has produced and operates a wide range of DrumScan® gamma measurement systems for monitoring packages, drums and boxed wastes arising from nuclear power plant reprocessing, fuel fabrication and decommissioning operations. The challenges associated with decommissioning operations are met by employing a range of technologies predominantly High Resolution and Low Resolution spectrometry (HRGS & LRGS). This paper describes how BNFL Instruments’ LRGS and HRGS DrumScan® gamma measurement systems have been used for the assay of uranium resides and potentially contaminated low level wastes by Capenhurst Integrated Decommissioning Project (IDP) in the UK. A description of the two Capenhurst segmented HRGS systems is included. Whilst Segmented Gamma Scanning is a well established technique for the non-destructive assay of gamma emitting radioisotopes in drummed waste, these systems utlise unique features to address the specific measurement requirements. The first system is configured for the accurate measurement of both small sized containers of uranium residues arising from recovery operations and low level wastes potentially contaminated with uranium contained in 200 litre drums. To achieve a high level of accuracy, this system uses a novel mechanical arrangement to overcome the wide variety of container sizes, and the unique “TransWeight” and “Transmission” matrix correction techniques which provide significant improvements over conventional Segmented Gamma Scanner matrix correction techniques. The second system is configured for Nuclear Safety purposes to provide an upper limit of the 235U present in 200 litre drums of potentially contaminated waste prior to the opening of the drums for sorting and uranium recovery operations. This system is configured to report an appropriately pessimistic upper estimate of the 235U present. A brief description of the LRGS systems used by Capenhurst is also provided. These systems have served to quantify the 235U content within a variety of potentially contaminated waste items ranging from 200 litre drums to 1m3 boxed waste.

Summary Structural, stratigraphic, and petrophysical uncertainties result in a wide range of geologic interpretations. For fields with a long production and pressure history, 3D dynamic simulations have been very useful in providing feedback to geologic modelers, which results in improved static models. For this study, we developed an integrated static and dynamic workflow to create a range of probabilistic simulation models to forecast dry-gas production under several production scenarios in the Chuchupa field. We selected eight geologic interpretations, representing the range of original gas in place (OGIP) and reservoir geometries determined in the static modeling, to perform dynamic history matches. The OGIP range of the models with very good history matches corresponds closely to the P10 to P90 OGIP range calculated from static modeling. In addition, we calibrated the various models with historical bottomhole and tubinghead flowing pressures and coupled the reservoir model with a network consisting of surface lines and equipment, pipelines from two platforms to the onshore sale-point station, and multistage compression to 1,215 psia. The set of probabilistic models is currently used to evaluate various production and market scenarios. Introduction Chuchupa field has produced 1.9 Tscf of dry gas, or approximately 40% of the OGIP. At the time of this study, three new horizontal wells were being planned, and new gas-sales agreements were being considered. Recent seismic reinterpretation, a new stratigraphic study, and a revision of the petrophysical model resulted in new probabilistic static models for the field. While these static models were being built, a parallel numerical-simulation study was conducted to determine the range of OGIP values that could be successfully history matched. Nine numerical reservoir models were generated by applying pore-volume multipliers to the prior-generation reservoir model, yielding a range of OGIP from 3.8 to 6.6 Tscf. We attempted to history match each of these nine models by using an optimization routine to adjust aquifer support, vertical transmissibility across a potential seal, and rock compressibility. The optimization routine proved to be a very useful and efficient tool to attain good-quality history matches in short periods of time. Good matches were obtained for models with OGIP ranging from 4.3 to 5.8 Tscf. On the basis of this information, the geologic modelers revised petrophysical parameters and generated 27 static models, encompassing three structural interpretations, three porosity distributions, and three possible positions of the gas/water contact (GWC). From experimental design, we obtained P10, P50, and P90values of 4.1, 4.7, and 5.3 Tscf, respectively. We scaled up and built reservoir-simulation models on eight of these models and performed history matches. The observed parameters to match were static well pressures and the absence of water production. Six of the eight models were satisfactorily history matched, with reasonable adjustments to aquifer strength, vertical transmissibility, and rock compressibility. The successfully history-matched models are within the P10 to P90 OGIP range. We selected three models to forecast future gas production. These models match the P10, P50, and P90 OGIP values determined in the probabilistic static model and combine the low, mid, and high structures, porosity and Swi distributions, and the range of GWC positions.

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Straight, conventional keyboards are still the most popular design among those shipped with new personal computer sales and standalone keyboard retail sales. Many keyboard users are reluctant to switch to a more ergonomic keyboard -designs that reduce awkward wrist postures. Ergonomic research led to a design of a new keyboard providing more ergonomic benefit to the masses of conventional, straight keyboard users while being equally or even more preferred. The result was a keyboard: Microsoft Comfort Curve © Keyboard, designed with a subtle split angle of 12° (instead of 24° of traditional ergonomic keyboards), extending the keys' sizes within this split. The design goals were to reduce ulnar deviation and to maintain approachability and typing performance.