AE-C attitude determination and control prelaunch analysis and operations plan

A description of attitude control support being supplied by the Mission and Data Operations Directorate is presented. Included are descriptions of the computer programs being used to support the missions for attitude determination, prediction, and control. In addition, descriptions of the operating procedures which will be used to accomplish mission objectives are provided

Count three for wear able computers

This paper is a postprint of a paper submitted to and accepted for publication in the Proceedings of the IEE Eurowearable 2003 Conference, and is subject to Institution of Engineering and Technology Copyright. The copy of record is available at the IET Digital Library. A revised version of this paper was also published in Electronics Systems and Software, also subject to Institution of Engineering and Technology Copyright. The copy of record is also available at the IET Digital Library.A description of 'ubiquitous computer' is presented. Ubiquitous computers imply portable computers embedded into everyday objects, which would replace personal computers. Ubiquitous computers can be mapped into a three-tier scheme, differentiated by processor performance and flexibility of function. The power consumption of mobile devices is one of the most important design considerations. The size of a wearable system is often a design limitation

Variation of turbulent burning rate of methane, methanol, and iso-octane air mixtures with equivalence ratio at elevated pressure

Turbulent burning velocities for premixed methane, methanol, and iso-octane/air mixtures have been experimentally determined for an rms turbulent velocity of 2 m/s and pressure of 0.5 MPa for a wide range of equivalence ratios. Turbulent burning velocity data were derived using high-speed schlieren photography and transient pressure recording; measurements were processed to yield a turbulent mass rate burning velocity, utr. The consistency between the values derived using the two techniques, for all fuels for both fuel-lean and fuel-rich mixtures, was good. Laminar burning measurements were made at the same pressure, temperature, and equivalence ratios as the turbulent cases and laminar burning velocities and Markstein numbers were determined. The equivalence ratio (φ) for peak turbulent burning velocity proved not always coincident with that for laminar burning velocity for the same fuel; for isooctane, the turbulent burning velocity unexpectedly remained high over the range φ = 1 to 2. The ratio of turbulent to laminar burning velocity proved remarkably high for very rich iso-octane/air and lean methane/air mixtures

Development of a high-performance transtibial cycling-specific prosthesis for the London 2012 Paralympic Games

Background and Aim It has been reported that cycling-specific research relating to participants with an amputation is extremely limited in both volume and frequency. However, practitioners might participate in the development of cycling-specific prosthetic limbs. This technical note presents the development of a successful design of a prosthetic limb developed specifically for competitive cycling. Technique This project resulted in a hollow composite construction which was low in weight and shaped to reduce a rider’s aerodynamic drag. Discussion The new prosthesis reduces the overall mass of more traditional designs by a significant amount yet provides a more aerodynamic shape over traditional approaches. These decisions have yielded a measurable increase in cycling performance. Whilst further refinement is needed to reduce the aerodynamic drag as much as possible, this project highlights the benefits that can exist by optimising the design of sports-specific prosthetic limbs

Real-time digital-computer-hardware simulation of a spacecraft with control-moment-gyroscope stabilization

Computer simulation of Apollo Telescope Mount to evaluate performance of control moment gyroscope system used for stabilizatio

Rotational Effects of Twisted Light on Atoms Beyond the Paraxial Approximation

The transition probability for the emission of a Bessel photon by an atomic system is calculated within first order perturbation theory. We derive a closed expression for the electromagnetic potentials beyond the paraxial approximation that permits a systematic multipole approximation . The matrix elements between center of mass and internal states are evaluated for some specially relevant cases. This permits to clarify the feasibility of observing the rotational effects of twisted light on atoms predicted by the calculations. It is shown that the probability that the internal state of an atom acquires orbital angular momentum from light is, in general, maximum for an atom located at the axis of a Bessel mode. For a Gaussian packet, the relevant parameter is the ratio of the spread of the atomic center of mass wave packet to the transversal wavelength of the photon.Comment: 10 pages, no figure

Science religion encounters, epistemic trespass, neighbourliness and overlapping domains: theorisation and quantitative evidence of extent

This study advances a concept of science religion encounter (SRE), with preliminary theorisation and shares findings on the extent and nature of such encounters reported by secondary religious education and science teachers. SREs are interdisciplinary engagements in classrooms involving subject knowledge from more than one subject. The researchers hypothesised they may arise unexpectedly, when a pupil asks a question, or be teacher-planned and intended. This article further elaborates the concept of SRE with reference to the concepts of ‘epistemic trespassing’ (ET), epistemic neighbourliness, and overlapping domains, introducing these to the field of education. The study is contextualised in the school classroom with quantitative data gathered among beginning and experienced teachers measuring whether this ET in SRE topics enter the classroom via ‘spontaneity’ or via a ‘deliberateness’. This clarifies the different roles a teacher may play and offers considerations for teacher development when navigating an SRE in ways that potentially reduce lost learning