SPIKE-2: a Practical Stirling Engine for Kilowatt Level Solar Power

Recent advances in the art of free piston Stirling engine design make possible the production of 1-10kW free piston Stirling linear alternator engine, hermetically sealed, efficient, durable and simple in construction and operation. Power output is in the form of single or three phase 60 Hz. AC, or DC. The three phase capability is available from single machines without need of external conditioning. Engine voltage control regains set voltage within 5 cycles in response to any load change. The existing SPIKE-2 design has an engine alternator efficiency of 25% at 650 C heater wall temperature and a service life of over three years in solar service. The same system can be scaled over a range of at least 100 watts to 25kW

Rhinologic changes in Wegener's granulomatosis

Twenty-eight patients with a clinical diagnosis of sinonasal Wegener's granulomatosis were referred for imaging during the period 1990-2001. Of these, 10 had clinical symptoms and signs confined to the nose and sinuses and 18 had classical systemic Wegener's. The computed tomography (CT) and magnetic resonance (MRI) scans of the series were reviewed by a panel of one otolaryngologist and two radiologists. From the total of 28 patients, 85.7 per cent showed non-specific mucosal thickening in the nasal cavity or paranasal sinuses, 75 per cent showed evidence of bone destruction, and 50 per cent new bone formation in the walls of the sinus cavities. In addition the orbit was affected in 30 per cent of patients.The diagnosis of systemic Wegener's granulomatosis is made clinically but the condition may present characteristic features on imaging by CT and MRI. In a patient without a history of previous sinonasal surgery, a combination of bone destruction and new bone formation on CT is virtually diagnostic of Wegener's especially when accompanied on MRI by a fat signal from the sclerotic sinus wall. These changes are important diagnostically in localized sinonasal Wegener's granulomatosis where the clinical diagnosis may be uncertain and the cANCA test can be negative

Free-piston Stirling engine conceptual design and technologies for space power, phase 1

As part of the SP-100 program, a phase 1 effort to design a free-piston Stirling engine (FPSE) for a space dynamic power conversion system was completed. SP-100 is a combined DOD/DOE/NASA program to develop nuclear power for space. This work was completed in the initial phases of the SP-100 program prior to the power conversion concept selection for the Ground Engineering System (GES). Stirling engine technology development as a growth option for SP-100 is continuing after this phase 1 effort. Following a review of various engine concepts, a single-cylinder engine with a linear alternator was selected for the remainder of the study. The relationships of specific mass and efficiency versus temperature ratio were determined for a power output of 25 kWe. This parametric study was done for a temperature ratio range of 1.5 to 2.0 and for hot-end temperatures of 875 K and 1075 K. A conceptual design of a 1080 K FPSE with a linear alternator producing 25 kWe output was completed. This was a single-cylinder engine designed for a 62,000 hour life and a temperature ratio of 2.0. The heat transport systems were pumped liquid-metal loops on both the hot and cold ends. These specifications were selected to match the SP-100 power system designs that were being evaluated at that time. The hot end of the engine used both refractory and superalloy materials; the hot-end pressure vessel featured an insulated design that allowed use of the superalloy material. The design was supported by the hardware demonstration of two of the component concepts - the hydrodynamic gas bearing for the displacer and the dynamic balance system. The hydrodynamic gas bearing was demonstrated on a test rig. The dynamic balance system was tested on the 1 kW RE-1000 engine at NASA Lewis

Dynamic stability of a uniform free-free beam under a gimbaled thrust of periodically varying magnitude

Dynamic stability of bending vibrations of uniform free-free beam under end thrust with application to rocket vehicle

A Qualitative Investigation Into the Impact of the Basketball Learning Intervention Programme (BLIP) on Disengaged Secondary School Students in the United Kingdom

This paper will evaluate the longitudinal effects of a basketball based intervention programme that targeted ten disengaged male secondary school students at a school in the Kent, England. The programme aimed to improve the behaviour and academic performance of the participants through a weekly intervention carried out by an external basketball player and coach providing academic support, mentoring and specially designed basketball sessions. Sports interventions have been deemed to provide a positive short-term impact on young people. However, researchers have identified the need for a longitudinal approach in order to examine the effects of such interventions post involvement as supported. This study involved five former Basketball Learning Intervention Programme (BLIP) members (with a mean age of 16.4 SD± 0.55 years) that were interviewed using semi-structured interview approach, 12 months after completing the intervention. Interpretative Phenomenological Analysis (IPA) revealed four superordinate and eleven subordinate themes. The four superordinate themes were; ‘baseline behaviours pre-intervention’, ‘immediate outcomes of the BLIP’, ‘impact of the coach’ and ‘long standing transferable outcomes’. The results revealed an immediate impact in comparison to the baseline behaviours of the participants pre-intervention. The data suggested that one of the most effective aspects of the programme was the positive impact of the coach on the participants. More importantly, this is the only study to report long-term improvements amongst the participants in terms of behaviour and academics as a result of engagement in a sports based intervention