A TREETOPS simulation of the Hubble Space Telescope-High Gain Antenna interaction

Virtually any project dealing with the control of a Large Space Structure (LSS) will involve some level of verification by digital computer simulation. While the Hubble Space Telescope might not normally be included in a discussion of LSS, it is presented to highlight a recently developed simulation and analysis program named TREETOPS. TREETOPS provides digital simulation, linearization, and control system interaction of flexible, multibody spacecraft which admit to a point-connected tree topology. The HST application of TREETOPS is intended to familiarize the LSS community with TREETOPS by presenting a user perspective of its key features

Controls, Astrophysics, and Structures Experiment in Space (CASES)

As the size and performance requirements of future NASA and DOD spacecrafts and payloads tend to increase, the associated control systems that must effect these requirements tend to interact with the vehicle's structural dynamics. Some of the Control Structure Interaction (CSI) issues are being addressed in a flight experiment which is entitled CASES (Controls, Astrophysics and Structures Experiment in Space). As one of the first CSI flight experiments, the main emphasis for CASES is to provide a test bed for validating CSI developments and simultaneously, to pave the way for subsequent CSI experiments and science missions by establishing precedents for flight qualifying Large Space Structures (LSS)-class spacecraft. In addition, CASES provides an opportunity to obtain data bases for in-space controls and structures experiments and, at the same time, to gather hard x ray data from pertinent galactic sources

The Ignatian renewal : a case study of a long-term, multi-phase process of educational change

This thesis drew upon the resources of philosophical hermeneutics to construct a conceptual framework for understanding the process of educational change. The experience of a particular case of change was then analysed from the perspective of the hermeneutic change agency framework. The conceptual framework for the thesis was developed from the writings of Hans-Georg Gadamer and also from writers who engaged with Gadamer, most notably, Paul Ricoeur and Jurgen Habermas. The retrieval orientation in Gadamer's hermeneutics was balanced by the critical analyses of Ricoeur and Habermas. Gadamer's notion of the 'fusion of horizons' was presented as the culmination of the change process: a fusion between the horizon of the change text, and the horizons of the change process participants. The thesis explored the potential of hermeneutic strategies such as play and conversation as a means to animate a hermeneutic form of change agentry. The case investigated in this thesis was a change process comprised of four strategies conducted over the years 1980 to 1996 at a Jesuit school located on the east coast of Australia. The change strategies aimed to promote the Jesuit ethos of the school and hence have been described in this thesis as 'ethos strategies'. The purpose of the thesis was not to evaluate the success of the ethos strategies, it was to explore how insights derived from philosophical hermeneutics could illuminate an analysis of the lived experience of a particular case of change. The subject matter of this thesis is timely because many Catholic schools are currently in a period of transition from a leadership exercised by Religious (nuns, brothers or priests) to a leadership exercised by lay people. The thesis situated the ethos programs in their theological and demographic contexts by presenting relevant theological developments from the Second Vatican Council and by describing the sharp decrease in the numbers of Religious personnel available to work in the schools. The teacher response to the ethos programs was considered in the context of the many practical difficulties associated with the scheduling of teacher development programs in fast-moving and busy schools. Although this thesis was particularly focused on change strategies that were conducted in the context of Jesuit education, the thesis is more generally situated in the research literature on educational change. The hermeneutic orientation of this thesis highlighted the elements of understanding, interpretation and meaning, and these elements are given some prominence in the more recent research literature on the change process. The complexity of change and the cultural dimension of the change process has been emphasised in the most recent educational change research literature and these themes have also found expression in this thesis. Participant observation, document analysis and qualitative interviews were used as data collection strategies for the case study in this thesis. The researcher was actively involved in the events investigated in the case study, and a case narrative was developed from the researcher's experience as a change agent responsible for implementing one of the change strategies at the case site. The case narrative was written in the first person and from the perspective of the researcher as a change manager. The methodology of the research was grounded in the hermeneutic insight that understanding and tact lies at the heart of the research process, rather than procedure and method. Hermeneutic research relies upon a capacity to identify and respond to the question that is presented by the expression of life being understood. Change agentry was presented in this thesis as unfolding in a middle space between the familiarity of current practice and the unfamiliarity of the new world that a change process seeks to open up. Hermeneutics has long understood that that interpretation would be impossible if the expressions of life were totally alien and unnecessary if there was nothing alien in them. A hermeneutic approach to change agentry seeks to discover points of commonality and points of challenge between the world of current practice and the world that the change process would open up. This thesis points to the tactful and dialogical dimensions of change agency when it is considered from the vantage point of philosophical hermeneutics

Effectively Managing the Air Force Enterprise Architecture

The Air Force is developing and implementing an enterprise architecture to meet the Clinger-Cohen Act\u27s requirement that all federal agencies use an architecture to guide their information technology (IT) investments. However, this act does not provide guidance on how to effectively manage an enterprise architecture. Prior research applied maturity models and competency stages to manage an enterprise architecture by defining layers of enterprise architecture management maturity. However, these efforts tend to view enterprise architecture development as a one-time planning process rather than an iterative progression. Enterprise architecture is not a one-time exercise, but rather it is an on-going effort within the organization to rationalize, integrate, and optimize the IT capability within an organization across many projects and business units. Hence, the critical success factors to effectively manage an enterprise architecture must be identified to ensure the structure, processes, and governing mechanisms are established within the organization for maintaining an enterprise architecture. This research draws from existing academic, professional, and government literature to identify the key issues affecting the Air Force\u27s ability to manage its enterprise architecture effectively. Once identified, a quantitative analysis will assist in interpreting the qualitative findings in hopes of determining the underlying factors driving these issues

Distributed control using linear momentum exchange devices

MSFC has successfully employed the use of the Vibrational Control of Space Structures (VCOSS) Linear Momentum Exchange Devices (LMEDs), which was an outgrowth of the Air Force Wright Aeronautical Laboratory (AFWAL) program, in a distributed control experiment. The control experiment was conducted in MSFC's Ground Facility for Large Space Structures Control Verification (GF/LSSCV). The GF/LSSCV's test article was well suited for this experiment in that the LMED could be judiciously placed on the ASTROMAST. The LMED placements were such that vibrational mode information could be extracted from the accelerometers on the LMED. The LMED accelerometer information was processed by the control algorithms so that the LMED masses could be accelerated to produce forces which would dampen the vibrational modes of interest. Experimental results are presented showing the LMED's capabilities

A framework for understanding the contributions of local residents to protected area law enforcement

Terrestrial and marine protected areas have long been championed as an approach to biodiversity conservation. For protected areas to be effective, equitable and inclusive, the involvement of local residents in their management and governance is considered important. Globally, there are many approaches to involving local residents in protected area law enforcement. However, opportunities for comparing different approaches have been limited by the lack of a clear common framework for analysis. To support a more holistic understanding, we present a framework for analysing the contributions of local residents to protected area law enforcement. Informed by a review of the literature and discussions with conservation practitioners, the framework comprises five key dimensions: (1) the different points in the enforcement system at which local residents are involved, (2) the nature of local participation in decision-making, (3) the type of external support provided to local residents, (4) the different motivating forces for participation, and (5) the extent to which local participation is formalized. We apply the framework to three real-world case studies to demonstrate its use in analysing and comparing the characteristics of different approaches. We suggest this framework could be used to examine variation in local participation within the enforcement system, inform evaluation and frame constructive discussions between relevant stakeholders. With the global coverage of protected areas likely to increase, the framework provides a foundation for better understanding the contributions of local residents to protected area law enforcement

Lattice calculation of 1/p21/p^2 corrections to αs\alpha_s and of ΛQCD\Lambda_{\rm {QCD}} in the MOM~\widetilde{MOM} scheme

We report on very strong evidence of the occurrence of power terms in \as(p), the QCD running coupling constant in the $\widetilde{MOM}$ scheme, by analyzing non-perturbative measurements from the lattice three-gluon vertex between 2.0 and 10.0 GeV at zero flavor. While putting forward the caveat that this definition of the coupling is a gauge dependent one, the general relevance of such an occurrence is discussed. We fit $\Lambda_{\bar{\rm MS}}^{(n_f=0)}= 237 \pm 3 ^{+ 0}_{-10}$ MeV in perfect agreement with the result obtained by the ALPHA group with a totally different method. The power correction to \as(p) is fitted to $(0.63\pm 0.03 ^{+ 0.0}_{- 0.13}) {\rm GeV}^2/p^2$.Comment: 21 pages, 3 figure

Should we welcome robot teachers?

Abstract Current uses of robots in classrooms are reviewed and used to characterise four scenarios: (s1) Robot as Classroom Teacher; (s2) Robot as Companion and Peer; (s3) Robot as Care-eliciting Companion; and (s4) Telepresence Robot Teacher. The main ethical concerns associated with robot teachers are identified as: privacy; attachment, deception, and loss of human contact; and control and accountability. These are discussed in terms of the four identified scenarios. It is argued that classroom robots are likely to impact children’s’ privacy, especially when they masquerade as their friends and companions, when sensors are used to measure children’s responses, and when records are kept. Social robots designed to appear as if they understand and care for humans necessarily involve some deception (itself a complex notion), and could increase the risk of reduced human contact. Children could form attachments to robot companions (s2 and s3), or robot teachers (s1) and this could have a deleterious effect on their social development. There are also concerns about the ability, and use of robots to control or make decisions about children’s behaviour in the classroom. It is concluded that there are good reasons not to welcome fully fledged robot teachers (s1), and that robot companions (s2 and 3) should be given a cautious welcome at best. The limited circumstances in which robots could be used in the classroom to improve the human condition by offering otherwise unavailable educational experiences are discussed