http://hdl.handle.net/2142/5130 (No description provided) Search the Channel search https://www.ideals.uiuc.edu/simple-search http://hdl.handle.net/2142/8899 Title: Reassembling Writing Technologies: Historical and Situated Studies of Rhetorical Activity <br/> <br/>Authors: Van Ittersum, Derek <br/> <br/>Abstract / Summary: Through historical research on hypertextual, collaborative writing software and hardware in the 1960s and situated studies of writers’ digital memory and invention work in the present, this dissertation considers the emergent uses of technologies surrounding disruptive moments. Combining Bruno Latour’s actor-network theory with theories of mediated activity (Vygotsky, Wertsch, Engeström, Nardi), it uses historical and contemporary scenes to propose that the coordination of mediating technologies constitutes important rhetorical work. Breakdowns in literate practices lead to the opening of what Latour has called black boxes, which otherwise would conceal the mediating roles of artifacts, people, and ideologies. Thus, breakdowns provide opportunities to trace the connections between situated activity and wider social contexts. Reconsidering the history of Douglas Engelbart’s On-Line System (NLS) of the 1960s and 70s, I illustrate how the black-boxing of a specific group of technologies into the standard personal computer suppressed alternate configurations that were supported by writing theories strongly resembling those of the early process movement. Through interviews with, and observations of, writers today as they demonstrate their digital note-taking and bibliographic work, I explore the breakdowns they encounter in the course of adopting new technologies and examine how functional systems (consisting of institutions, conventions, people, and artifacts) shape and respond to these writers’ goals for their literate practices. The historical and contemporary case studies suggest that writers, teachers, and designers working within digital environments can benefit from increased consideration of the role of computing practices and artifacts in rhetorical work. <br/> <br/>Keywords: Rhetoric; Computers and writing; Engelbart, Douglas; Writing Studies http://hdl.handle.net/2142/8886 Title: Gait Regulation for Bipedal Locomotion <br/> <br/>Authors: Holm, Jonathan K. <br/> <br/>Abstract / Summary: This work explores regulation of forward speed, step length, and slope walking for the passive-dynamic class of bipedal robots. Previously, an energy-shaping control for regulating forward speed has appeared in the literature; here we show that control to be a special case of a more general time-scaling control that allows for speed transitions in arbitrary time. As prior work has focused on potential energy shaping for fully actuated bipeds, we study in detail the shaping of kinetic energy for bipedal robots, giving special treatment to issues of underactuation. Drawing inspiration from features of human walking, an underactuated kinetic-shaping control is presented that provides efficient regulation of walking speed while adjusting step length. Previous results on energetic symmetries of bipedal walking are also extended, resulting in a control that allows regulation of speed and step length while walking on any slope. Finally we formalize the optimal gait regulation problem and propose a dynamic programming solution seeded with passive-dynamic limit cycles. Observations of the optimal solutions generated by this method reveal further similarities between passive dynamic walking and human locomotion and give insight into the structure of minimum-effort controls for walking. <br/> <br/>Keywords: biped; robot; passive; walking; passive-dynamic; energy shaping; optimal; control http://hdl.handle.net/2142/8857 Title: Studies of Protein-Protein and Protein-Water Interactions by Small Angle X-Ray Scattering, Terahertz Spectroscopy, ASMOS, And Computer Simulation <br/> <br/>Authors: Kim, Seung Joong <br/> <br/>Abstract / Summary: The protein folding problem has been one of the most challenging subjects in biological physics due to its complexity. Energy landscape theory based on statistical mechanics provides a thermodynamic interpretation of the protein folding process. We have been working to answer fundamental questions about protein-protein and protein-water interactions, which are very important for describing the energy landscape surface of proteins correctly. At first, we present a new method for computing protein-protein interaction potentials of solvated proteins directly from SAXS data. An ensemble of proteins was modeled by Metropolis Monte Carlo and Molecular Dynamics simulations, and the global X-ray scattering of the whole model ensemble was computed at each snapshot of the simulation. The interaction potential model was optimized and iterated by a Levenberg-Marquardt algorithm. Secondly, we report that terahertz spectroscopy directly probes hydration dynamics around proteins and determines the size of the dynamical hydration shell. We also present the sequence and pH-dependence of the hydration shell and the effect of the hydrophobicity. On the other hand, kinetic terahertz absorption (KITA) spectroscopy is introduced to study the refolding kinetics of ubiquitin and its mutants. KITA results are compared to small angle X-ray scattering, tryptophan fluorescence, and circular dichroism results. We propose that KITA monitors the rearrangement of hydrogen bonding during secondary structure formation. Finally, we present development of the automated single molecule operating system (ASMOS) for a high throughput single molecule detector, which levitates a single protein molecule in a 10 µm diameter droplet by the laser guidance. I also have performed supporting calculations and simulations with my own program codes. <br/> <br/>Keywords: SAXS; Terahertz; Small angle X-Ray scattering; Simulation; KITA; THz; Protein-protein interaction; Biophysics; Protein-water interaction; hydration http://hdl.handle.net/2142/5160 Title: Fractional derivative models and their use in the characterization of hydropolymer and in-vivo breast tissue viscoelasticity <br/> <br/>Authors: Coussot, Cecile <br/> <br/>Abstract / Summary: The Viscoelastic response of hydropolymers, which include gelatin phantom and glandular breast tissue, may be accurately characterized with as few as three parameters using the Kelvin-Voigt Fractional Derivative (KVFD) modeling approach. We propose to image these parameters for simulated and experimental imaging phantoms and to estimate them for normal and cancerous in-vivo breast tissues. After a detailed presentation of the processing algorithm and discussion of its performances, we analyze the KVFD parameter values in simulated and experimental hydrogels. We show that the KVFD parameters can separate the biphasic mechanical properties of hydropolymers that describe the response of its solid and fluidic components and present the effects of pH and concentration changes in gelatin phantoms. We then interpret average results observed in normal and cancerous breast tissues and show that this modeling approach may be applied to tumor differentiation. <br/> <br/>Keywords: Fractional derivative models; Viscoelasticity http://hdl.handle.net/2142/5129 Title: Reasoning with Plans: Inference of Semantic Relationships Among Plans About Urban Development <br/> <br/>Authors: Kaza, Nikhil <br/> <br/>Abstract / Summary: Plans have been considered the end products of planning activity, and research has focused on how plans are made. Careful thought has not been accorded to how plans are used, after they are made, in reasoning about and choosing how to act. In any given situation, various organisations make plans, some of which have overlapping scopes and intersecting intentions. As a result, the actions considered in these plans have semantic relationships such as substitutability, interdependence, and contingency with one another. The purpose of this dissertation is to identify and explain the semantic relationships between actions within and among plans to better understand how to reason with plans and about actions. The thesis defended is that it is useful and possible to reason from multiple plans when deciding what to do. A plan contains information about interdependencies and uncertainties of multiple decisions and actions considered by an actor. These relationships are not limited to actions within one’s own purview. One has to consider also the effects of others’ actions and intentions on one’s own. Since a single plan cannot account for all these interdependencies even for one actor, every actor should consider multiple plans–both plans of her own and those of others–in making decisions. This dissertation examines the various plans made over time by various organisations in McHenry and Champaign counties in Illinois. Relationships between ii actions within and among multiple plans can be discovered using attributes of actions and the configurations of actions within a single plan so that they can be considered in future planning and decision making. It builds upon multiple disciplines and methodologies to represent actions, situations, intentions, and relationships among them. Simple databases based on real situations were used to demonstrate that these relationships can be encoded and queried in reasoning with plans. The results demonstrated that previously discovered semantic relationships can be used to discover additional relationships across plans thereby enriching the decision making. The approach provides a systematic way of structuring the information in plans so that reasoning about relationships among actions across multiple plans is possible. <br/> <br/>Keywords: Plans; Interdependence; Organizations; Intentions; Substitutability http://hdl.handle.net/2142/3535 Title: Illinois Public Community College Department Chair Roles and Role Conflict <br/> <br/>Authors: Young, Kristine M. <br/> <br/>Abstract / Summary: This research had two purposes: to determine community college department chair roles and to determine whether role conflict exists for the status of Illinois public community college department chair. The research was divided into two phases. In Phase I, community college department chair role factors were determined. Using ratings of importance reported by a sample of Illinois public community college department chairs on a modified version of Carroll and Gmelch’s (1992) department chair duty questionnaire, principal components analysis was employed to determine an underlying factor structure. Five factors were determined and interpreted as department chair roles: Department Leader, Resource Manager, Faculty Leader, Instructional Manager, and Teacher and Student Adviser. It was also determined whether the importance placed on department chair roles varied by department chair characteristic variables of academic discipline, departmental disciplinary composition, size of department, length of service as chair, whether the chair was elected by faculty or selected by administration, number of years served as a full-time faculty member prior to becoming department chair, and teaching load. Results indicated that certain characteristic variables of Illinois public community college department chairs influence the importance they ascribe to department chair roles. It was also determined in Phase I that role conflict and role overload exist to a mild to moderate extent for the Illinois public community college department chair status. In addition, a specific expression of role overload, namely, department chairs spending an inordinate amount of time performing roles they find of greater importance, may have been determined. In Phase II, the complete role set of department chairs, faculty, and the chief academic officer at one Illinois public community college was studied. It was determined that with minor exceptions, full-time faculty, part-time faculty, and the chief academic officer ascribed the same level of importance to the roles determined in Phase I as did the department chairs. Additionally, no statistically significant differences were found on the importance ascribed to department chair roles based on departmental disciplinary composition or length of faculty service by full and part-time faculty. <br/> <br/>Keywords: Department chairs; Roles; Community Colleges