5,199 research outputs found
Orbital Maneuvering system design evolution
Preliminary design considerations and changes made in the baseline space shuttle orbital maneuvering system (OMS) to reduce cost and weight are detailed. The definition of initial subsystem requirements, trade studies, and design approaches are considered. Design features of the engine, its injector, combustion chamber, nozzle extension and bipropellant valve are illustrated and discussed. The current OMS consists of two identical pods that use nitrogen tetroxide (NTO) and monomethylhydrazine (MMH) propellants to provide 1000 ft/sec of delta velocity for a payload of 65,000 pounds. Major systems are pressurant gas storage and control, propellant storage supply and quantity measurement, and the rocket engine, which includes a bipropellant valve, an injector/thrust chamber, and a nozzle. The subsystem provides orbit insertion, circularization, and on orbit and deorbit capability for the shuttle orbiter
Skills, Work and Work and Lifelong Learning Lifelong Learning: The Role of Guidance
Within the UK, much attention has been given to focusing on the skills of the workforce and identifying adult skill shortages within traditional, new, and evolving economies. An in-depth analysis of labour market demands and skill shortages is presented which provides strong evidence that in order to ensure the future success of the UK economy, a significant increase in the number of adults engaged in learning is crucial.
It is suggested that if we are to persuade more adults to participate in productive work-related learning, help them make appropriate choices relative to their interests and capabilities, and support them to persist and succeed, this will require a wide set of capabilities within future
adult guidance provision. This has significant implications for the development of adult guidance services in the UK, and offers real challenges to policy-makers and practitioners to find innovative ways of inspiring and motivating individuals and employers to invest in learning and personal development
Design and operation of a solar heating and cooling system for a residential size building
The first year of operation of solar house is discussed. Selected design information, together with a brief system description is included. The house was equipped with an integrated solar heating and cooling system which uses fully automated state-of-the art. Evaluation of the data indicate that the solar house heating and cooling system is capable of supplying nearly 100 percent of the thermal energy required for heating and approximately 50 percent of the thermal energy required to operate the absorption cycle air conditioner
Discourses Of Prejudice In The professions: The Case Of Sign Languages
There is no evidence that learning a natural human language is cognitively harmful to children. To the contrary, multilingualism has been argued to be beneficial to all. Nevertheless, many professionals advise the parents of deaf children that their children should not learn a sign language during their early years, despite strong evidence across many research disciplines that sign languages are natural human languages. Their recommendations are based on a combination of misperceptions about (1) the difficulty of learning a sign language, (2) the effects of bilingualism, and particularly bimodalism, (3) the bona fide status of languages that lack a written form, (4) the effects of a sign language on acquiring literacy, (5) the ability of technologies to address the needs of deaf children and (6) the effects that use of a sign language will have on family cohesion. We expose these misperceptions as based in prejudice and urge institutions involved in educating professionals concerned with the healthcare, raising and educating of deaf children to include appropriate information about first language acquisition and the importance of a sign language for deaf children. We further urge such professionals to advise the parents of deaf children properly, which means to strongly advise the introduction of a sign language as soon as hearing loss is detected
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