A logistics and potential hazard study of propellant systems for a Saturn 5 derived heavy lift (three-stage core) launch vehicle

The Bush Administration has directed NASA to prepare for a return to the Moon and on to Mars - the Space Exploration Initiative. To meet this directive, powerful rocket boosters will be required in order to lift payloads that may reach the half-million pound range into low earth orbit. In this report an analysis is presented on logistics and potential hazards of the propellant systems envisioned for future Saturn 5 derived heavy lift launch vehicles. In discussing propellant logistics, particular attention has been given to possible problems associated with procurement, transportation, and storage of RP-1, HL2, and LOX, the heavy lift launch vehicle propellants. Current LOX producing facilities will need to be expanded and propellant storage and some support facilities will require relocation if current Launch Pads 39A and/or 39B are to be used for future heavy noise-abatement measures. Included in the report is a discussion of suggested additional studies, primarily economic and environmental, which should be undertaken in support of the goals of the Space Exploration Initiative

Design and control of remote manipulators

Results of investigations on vibrational modes of manipulators revealed: (1) any arbitrary manipulator may be analyzed for its small motion compliances; (2) a simulation of the Martin-Marietta shuttle boom with a 65,000 lb. payload attached, indicated three natural frequencies; and (3) simulations can be made of rigid limbs and flexible joints as well as for flexible limbs and locked joints and combinations thereof. Trajectories for arms were determined so that some integral criterion such as integral of kinetic energy or control torque magnitude is minimized over a motion of the arm. Experiments performed to evaluate various TV displays in conjunction with manipulator control modes showed that when mounted directly to the manipulator control arm and arranged to look approximately along the arm to the hand the operator could perform the task almost as quickly as when viewing the task directly

An exploration of autistic adolescent female’s educational experiences within mainstream secondary school

Research exploring education and autism has become oversaturated with the perspectives of non-autistics (Nicholas et al., 2019; Richards & Crane, 2020; Tesfaye et al., 2019). Previous studies have highlighted the unique challenges autistic adolescent pupils’ experience within mainstream secondary school (Symes and Humphrey, 2011; Brede et al., 2017; Moore, 2006; Humphrey and Lewis, 2008). Moyse and Porter (2015) explored what it was like being an autistic girl within regular primary education, however limited studies have solely concentrated on the voices of autistic adolescent females. The project explored the following research questions: - 1. What is school like for autistic females in a mainstream secondary school? 2. How can personal experiences and knowledge of autism support the development of a fully collaborative research approach to allow the voices of autistic females to be heard? 3. How can creative and personalised approaches be used to engage autistic participants This topic is particularly important to me, as an autistic female I really struggled in mainstream education. I believe that this doesn’t have to be the case for the next generation of autistic females. A group of 4 autistic adolescent girls from a mainstream secondary school within the UK took part in the project. A mixed method approach was utilized, adapted to the individual needs of the girls. A variety of data was collected and analysed using thematic analysis. The data gathered from the girls provided a unique insight into their school experiences at the time of this study. Interestingly all the girls were talented in various areas of creativity, providing them with stress relief, expression of self, as well as escapism. All the girls reported the importance of having friends, however, they often felt misunderstood by their peers and staff. Worryingly, the girls reported bullying and stigmatisation, it was clear that this had a detrimental impact on the girl’s well-being. An unexpected finding was the solidarity found in meeting and interacting with other autistic girls, as well as having an openly autistic teacher within the school

Improving outcomes in outsourced product development: a joint consultant-client perspective

Although firms increasingly outsource front end product development activities to production suppliers or design consultants, this practice has received little scholarly attention. The few existing academic studies report high failure rates but generally present only the client firms’ view of the causes. Our first results from in-depth interviews of both clients and consultants give a richer picture of enablers of success and causes of failure. We confirm some previous findings(internal divisions within the client, “poor communication” between parties),identify new ones (inadequate client capabilities, failure to transfer design intent), and combine them into a comprehensive model of outsourced product development that includes negotiating project scope, continuously managing expectations, and carefully re-integrating the design output into the client’s operations. Finally, we classify several types of client dependency (need for new ideas, extra capacity, or specific technical expertise) and highlight the particular hazards associated with each

Environmental effects on polymeric matrix composites

Current epoxy resins utilized in high performance structural composites absorb moisture from high humidity environments. Such moisture absorption causes plasticization of the resin to occur with concurrent swelling and lowering of the glass transition temperature. Similar effects are observed in composites. Data are presented showing the effects of absorbed moisture on Hercules AS/3501-5 graphite/epoxy composites. Prediction of moisture content and distribution in composites, along with reduction in mechanical properties, are discussed

The effectiveness of a double-stem injection valve in controlling combustion in a compression-ignition engine

An investigation was made to determine to what extent the rates of combustion in a compression-ignition engine can be controlled by varying the rates of fuel injection. The tests showed that the double-stem valve operated satisfactorily under all normal injection conditions; the rate of injection has a definite effect on the rate of combustion; the engine performance with the double-stem valve was inferior to that obtained with a single-stem valve; and the control of injection rates permitted by an injection valve of two stages of discharge is not sufficient to effect the desired rates of combustion