2,643 research outputs found
Fuel cells for power generation and organic waste treatment on the island of Mull
In-situ use of biomass and organic waste streams have the potential to provide the key to energy self sustainability for islands and remote communities. Traditionally biogas fuels have been used in combustion engines for electric power generation. However, fuel cells offer the prospect of achieving higher generating efficiencies, and additionally, important environmental benefits can be achieved by way of mitigating greenhouse gas emissions, whilst providing a carbon sink. This paper presents the design details of a biogas gas plant and fuel cell installation that will provide a practical solution on an island (and be applicable in other remote and rural areas) where connection to the grid can be expensive, and where biofuels can be produced on site at no significant extra cost
Antiphase dynamics in a multimode semiconductor laser with optical injection
A detailed experimental study of antiphase dynamics in a two-mode
semiconductor laser with optical injection is presented. The device is a
specially designed Fabry-Perot laser that supports two primary modes with a THz
frequency spacing. Injection in one of the primary modes of the device leads to
a rich variety of single and two-mode dynamical scenarios, which are reproduced
with remarkable accuracy by a four dimensional rate equation model. Numerical
bifurcation analysis reveals the importance of torus bifurcations in mediating
transitions to antiphase dynamics and of saddle-node of limit cycle
bifurcations in switching of the dynamics between single and two-mode regimes.Comment: 7 pages, 9 figure
Flight test pilot evaluation of a delayed flap approach procedure
Using NASA's CV-990 aircraft, a delayed flap approach procedure was demonstrated to nine guest pilots from the air transport industry. Four demonstration flights and 37 approaches were conducted under VFR weather conditions. A limited pilot evaluation of the delayed flap procedure was obtained from pilot comments and from questionaires they completed. Pilot acceptability, pilot workload, and ATC compatibility were quantitatively rated. The delayed flap procedure was shown to be feasible, and suggestions for further development work were obtained
Quantitative sensory testing in children with sickle cell disease: additional insights and future possibilities.
Quantitative sensory testing (QST) is used in a variety of pain disorders to characterize pain and predict prognosis and response to specific therapies. In this study, we aimed to confirm results in the literature documenting altered QST thresholds in sickle cell disease (SCD) and assess the test-retest reliability of results over time. Fifty-seven SCD and 60 control subjects aged 8-20 years underwent heat and cold detection and pain threshold testing using a Medoc TSAII. Participants were tested at baseline and 3 months; SCD subjects were additionally tested at 6 months. An important facet of our study was the development and use of a novel QST modelling approach, allowing us to model all data together across modalities. We have not demonstrated significant differences in thermal thresholds between subjects with SCD and controls. Thermal thresholds were consistent over a 3- to 6-month period. Subjects on whom hydroxycarbamide (HC) was initiated shortly before or after baseline testing (new HC users) exhibited progressive decreases in thermal sensitivity from baseline to 6 months, suggesting that thermal testing may be sensitive to effective therapy to prevent vasoocclusive pain. These findings inform the use of QST as an endpoint in the evaluation of preventative pain therapies
Delayed flap approach procedures for noise abatement and fuel conservation
The NASA/Ames Research Center is currently investigating the delayed flap approach during which pilot actions are determined and prescribed by an onboard digital computer. The onboard digital computer determines the proper timing for the deployment of the landing gear and flaps based on the existing winds and airplane gross weight. Advisory commands are displayed to the pilot. The approach is flown along the conventional ILS glide slope but is initiated at a higher airspeed and in a clean aircraft configuration that allows for low thrust and results in reduced noise and fuel consumption. Topics discussed include operational procedures, pilot acceptability of these procedures, and fuel/noise benefits resulting from flight tests and simulation
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A comparison of remote therapy, face to face therapy and an attention control intervention for people with aphasia: A quasi-randomised controlled feasibility study
Objective: To test the feasibility of a Randomised Controlled Trial comparing face to face and remotely delivered word finding therapy for people with aphasia
Design: A quasi-randomised controlled feasibility study comparing remote therapy delivered from a University lab, remote therapy delivered from a clinical site, face to face therapy and an attention control condition
Setting: A University lab and NHS outpatient service
Participants: Twenty-one people with aphasia following left hemisphere stroke
Interventions: Eight sessions of word finding therapy, delivered either face to face or remotely, were compared to an attention control condition comprising eight sessions of remotely delivered supported conversation. The remote conditions used mainstream video conferencing technology.
Outcome measures: Feasibility was assessed by recruitment and attrition rates, participant observations and interviews, and treatment fidelity checking. Effects of therapy on word retrieval were assessed by tests of picture naming and naming in conversation.
Results: Twenty-one participants were recruited over 17 months, with one lost at baseline. Compliance and satisfaction with the intervention was good. Treatment fidelity was high for both remote and face to face delivery (1251/1421 therapist behaviours were compliant with the protocol). Participants who received therapy improved on picture naming significantly more than controls (mean numerical gains: 20.2 (remote from University); 41 (remote from clinical site); 30.8 (face to face); 5.8 (attention control); p <.001). There were no significant differences between groups in the assessment of conversation.
Conclusions: Word finding therapy can be delivered via mainstream internet video conferencing. Therapy improved picture naming, but not naming in conversation
Flight tests of IFR landing approach systems for helicopters
Joint NASA/FAA helicopter flight tests were conducted to investigate airborne radar approaches (ARA) and microwave landing system (MLS) approaches. Flight-test results were utilized to prove NASA with a data base to be used as a performance measure for advanced guidance and navigation concepts, and to provide FAA with data for establishment of TERPS criteria. The first flight-test investigation consisted of helicopter IFR approaches to offshore oil rigs in the Gulf of Mexico, using weather/mapping radar, operational pilots, and a Bell 212 helicopter. The second flight-test investigation consisted of IFR MLS approaches at Crows Landing (near Ames Research Center), with a Bell UH-1H helicopter, using NASA, FAA, and operational industry pilots. Tests are described and results discussed
Did a physician-targeted intervention that reduced potentially inappropriate prescribing to elderly patients also reduce related hospitalizations?
Objectives:
To determine whether a general practitioner focused intervention aimed at decreasing PIM prescribing in the elderly can decrease the risk of PIM-related hospitalizations.
Poster presented at 2016 ISPOR conference in Washington DC.https://jdc.jefferson.edu/jcphposters/1005/thumbnail.jp
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