Isolation characteristics of space telescope suspension systems Final technical report

Vibration isolation tests of spring, hysteresis, and magnetic suspension systems for spaceborne telescope

Dynamic Considerations for Control of Closed Life Support Systems

Reliability of closed life support systems depend on their ability to continue supplying the crew's needs during perturbations and equipment failures. The dynamic considerations interact with the basic static design through the sizing of storages, the specification of excess capacities in processors, and the choice of system initial state. A very simple system flow model was used to examine the possibilities for system failures even when there is sufficient storage to buffer the immediate effects of the perturbation. Two control schemes are shown which have different dynamic consequences in response to component failures

The PhD experience at the Australian National University

This paper presents an impression of the PhD-student experience at the Australian National University gained during my term as Dean of the Graduate School from 1990 to 1998. It is based mainly on comments made by individual students in 150 confidential "exit interviews" conducted from 1994 to 1998 inclusive, and, to a lesser extent, on matters raised in approximately 100 meetings requested by students throughout my term. Other activities arising from the role of Dean have also helped to mould my views,including, for example, 8 years as Chair of the University's Graduate Degrees Committee. The picture which emerges is strongly positive. It is clear that for most students the PhD experience at the ANU has been satisfying, productive, stimulating and enjoyable. Supervision is by far the matter of greatest concern to students. It appears that the overall quality of supervision provided for PhD students at the ANU is good, but there is variability, and 'horror stories'are sometimes heard. Student concerns include slow or superficial reading of written material by supervisors, lack of regular contact with supervisors, lack of supervisory expertise in the thesis topic, problems arising from the limitation of scholarship duration to three and a half years, gender-related matters, and plagiarism

Bless your heart but hide the children : the effect of entertainment media depictions of social workers on public opinions about social work as a profession

This study explored the effects of entertainment media depictions of social workers on public opinions of social work as a profession. Specifically, this study focused on the power of short clips depicting a social work character to influence participants’ views of social work as positive or negative and the social desirability of social work as a profession. One hundred and nineteen participants viewed a short video clip, which included a positive, negative, or no depiction of a social worker. Participants then completed a survey assessing positive or negative attitudes towards social workers and the desirability of social work as a profession. The video clips were found to have no significant influence on participants’ responses to the survey. Participant responses on the positive/negative subscale were found to be significantly more negative than neutral, and participants aged 18-40 years were found to be significantly less likely to see a social worker if they wanted therap

Devising A Show From the Ground Up: Things We (never) Learned in Sex Ed

Only 24 U.S. states, plus DC, mandate sex education. That’s less than half of the country. When the members of Portal Theatre, including myself, shared our own personal experiences with sex education, we found one thing in common: we were all unprepared. We were unprepared for sex, queer sex, consent, sexual health like menstration, STI’s, and yeast infections, etc. We all found there was something in our sex education that was lacking. To respond to the poor sex education of the United States, and in various countries around the world, we decided to share our experiences by creating a play. The play explores seven different topics in sex education; periods, first time having sex, sex educators, masturbation, abstinence, consent/assault, and bad sex advice. Using a variety of different theatrical styles, the two actors, Lindsay Spear and Phoebe Thompson explore how their sex education in school failed them in sometimes funny sometimes dramatic ways. This play will inform, entertain, and address the real experiences of people affected by bad sex education, to which the majority of the US is affected by. By analyzing the process of creating this show and touring it across different Fringe Festivals in Canada, I will break down the creative process of devising and building a show from the ground up. I will explain the process of researching, writing with other people, and the hardships of the creative and touring process. Throught this play and reflection, I hope this thesis encourages you to look into the sex education system in your own country, or gives you the courage to create your own show on a topic you are passionate about

Application of control theory to dynamic systems simulation

The application of control theory is applied to dynamic systems simulation. Theory and methodology applicable to controlled ecological life support systems are considered. Spatial effects on system stability, design of control systems with uncertain parameters, and an interactive computing language (PARASOL-II) designed for dynamic system simulation, report quality graphics, data acquisition, and simple real time control are discussed

A high-rate telemetry system for the Mariner Mars 1969 mission

High rate telemetry system for Mariner Mars 1969 missio

Control and modeling of a CELSS (Controlled Ecological Life Support System)

Research topics that arise from the conceptualization of control for closed life support systems which are life support systems in which all or most of the mass is recycled are discussed. Modeling and control of uncertain and poorly defined systems, resource allocation in closed life support systems, and control structures or systems with delay and closure are emphasized

An approach to the preliminary evaluation of Closed Ecological Life Support System (CELSS) scenarios and control strategies

Life support systems for manned space missions are discussed. A scenario analysis method was proposed for the initial step of comparing possible partial or total recycle scenarios. The method is discussed in detail

Oxygen-related traps in pentacene thin films: Energetic position and implications for transistor performance

We studied the influence of oxygen on the electronic trap states in a pentacene thin film. This was done by carrying out gated four-terminal measurements on thin-film transistors as a function of temperature and without ever exposing the samples to ambient air. Photooxidation of pentacene is shown to lead to a peak of trap states centered at 0.28 eV from the mobility edge, with trap densities of the order of 10(18) cm(-3). These trap states need to be occupied at first and cause a reduction in the number of free carriers, i.e. a consistent shift of the density of free holes as a function of gate voltage. Moreover, the exposure to oxygen reduces the mobility of the charge carriers above the mobility edge. We correlate the change of these transport parameters with the change of the essential device parameters, i.e. subthreshold performance and effective field-effect mobility. This study supports the assumption of a mobility edge for charge transport, and contributes to a detailed understanding of an important degradation mechanism of organic field-effect transistors. Deep traps in an organic field-effect transistor reduce the effective field-effect mobility by reducing the number of free carriers and their mobility above the mobility edge.Comment: 13 pages, 14 figures, to be published in Phys. Rev.