650 research outputs found
First 2.5 years of the High Energy Transient Explorer
No full textThesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2003.Includes bibliographical references (p. 121-126).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.The HETE satellite became operational on the 2nd of February, 2001. In the first 2.5 years of the mission prior to July 1 of 2003, 42 Gamma-ray bursts (GRBs) were promptly localized and publicized over the GRB Coordinates Network (GCN). The first part of this thesis deals with the detection of GRBs in data down-linked from the HETE satellite using a suite of automated routines. This "ground triggering" was designed to supplement the HETE on-board triggering systems. To date, it has facilitated the broadcast of six HETE GRBs to the GCN. A novel trigger search routine using wavelets, which is included in the suite, is discussed. Near real time searches for very long duration (> 300s) GRBs using this and other methods are presented. The second part of the thesis focuses on imaging observations with Chandra of two GRB X-ray afterglows and high-resolution spectroscopic observations of five GRB X-ray afterglows. The imaging observations explore the nature of the class of short/hard GRBs and the class of "optically dark" GRBs, while the spectroscopic observations probe the relation of the long/soft class of GRBs to supernovae. Our observations suggest that no long/soft GRBs are optically dark. Rather, many appear to be "optically faint." In one case, a short/hard GRB may have been optically dark, because it lacked entirely an afterglow in the optical, radio, and X-ray bands. Finally, If the emission lines we detect in a Chandra spectrum of the X-ray afterglow to GRB 020813 are real, then a supernova likely occurred 2 2 months prior to the GRB. The statistical significance of the discrete spectral features reported to date in high resolution spectra taken with Chandra are discussed in detail, as the believability of the features is critical to moving forward in the field.by Nathaniel Richard Butler.Ph.D
Richard Nathaniel (R.N.) Hogan Interview - Tape 1
No full textRichard Nathaniel Hogan (1902 –1997)
R.N. Hogan was born in Monroe County, Arkansas. He was adopted by G.P. Bowser and attended the school at Silver Point for a brief time and then the Southern Practical Institute in Nashville. When the Bowser family moved to Louisville, Kentucky, he went with them and finished school there. His preaching took him to most of the fifty states and he was instrumental in starting many congregations. In the interview, he talks about his evangelistic work, particularly in Texas, Oklahoma, California, and Chicago. He was minister of the Figeroa Church of Christ in Los Angeles, California, for many years. Hogan was instrumental in the founding of Southwestern Christian College in Terrell, Texas, and served on the Board of Directors. He is the author of several books and articles, including Sermons (1940), and was editor of the Christian Echo beginning in 1953. A scholarship has been established in his name at Pepperdine University. In the interview, Hogan talks about the experience of his family with slavery, black and white relations in the beginning of some African American churches, his early memories of the Church, inter-racial relations, and disputes in the Church concerning the role of the Elders
Richard Nathaniel (R.N.) Hogan Interview - Transcript
No full textRichard Nathaniel Hogan (1902 –1997)
R.N. Hogan was born in Monroe County, Arkansas. He was adopted by G.P. Bowser and attended the school at Silver Point for a brief time and then the Southern Practical Institute in Nashville. When the Bowser family moved to Louisville, Kentucky, he went with them and finished school there. His preaching took him to most of the fifty states and he was instrumental in starting many congregations. In the interview, he talks about his evangelistic work, particularly in Texas, Oklahoma, California, and Chicago. He was minister of the Figeroa Church of Christ in Los Angeles, California, for many years. Hogan was instrumental in the founding of Southwestern Christian College in Terrell, Texas, and served on the Board of Directors. He is the author of several books and articles, including Sermons (1940), and was editor of the Christian Echo beginning in 1953. A scholarship has been established in his name at Pepperdine University. In the interview, Hogan talks about the experience of his family with slavery, black and white relations in the beginning of some African American churches, his early memories of the Church, inter-racial relations, and disputes in the Church concerning the role of the Elders
The work that parks do: urban environmental management and its alternatives
No full textAs cities come to be seen as both the source of and the possible solution to a variety of environmental concerns, and as hubs of economic activity, it is increasingly important to understand the shifting meanings that are applied to them, their economies, and their connection to the non-human world. In this dissertation, I examine the city as a site of environmental discourse formation, where knowledge about the environment is produced, shaped, and changed, and where notions of “nature” and “society” develop in conjunction with an emerging understanding of environmental responsibility and identity. Through an examination of the establishment of urban parks in Philadelphia from the 19th century to the present, this project sheds light on the processes through which the urban and the natural have been and continue to be constituted. The central concern of this project is to understand how and why a particular knowledge of urban nature emerged, to uncover the techniques employed that produce and reinforce it, and to trace the positioning of subjects within urban, economic, and environmental discourses. To do this, I identify the sites in which this discourse is (re)produced, the disciplinary techniques and specific practices that produce parks as unique kinds of spaces or landscapes in the city, and the consequences of these framings for the way cities are imagined. I employ a range of research methods that includes text analysis, visual discourse analysis, participant observation, and focus group interviewing techniques.Ph.D.Includes bibliographical referencesby Nathaniel Joseph Gabrie
"That One Congenial Friend:" Hawthorne's Search for a Careful Reader
No full textThesis written by a student in the UNT Honors College discussing author Nathaniel Hawthorne's hidden warnings of hypocrisies and civil violations that would occur despite constitutional protections. The author argues that Hawthorne hid his warnings in allegory
The evolving reputation of Richard Hooker : an examination of responses to the Ecclesiastical Polity, 1640-1714.
No full textSIGLEAvailable from British Library Document Supply Centre-DSC:DXN033104 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Alienating Intimacy: Male Friendship and Author-Reader Relationship in the Antebellum Imagination
No full textThis dissertation examines representations of male friendship in antebellum American literature, moving beyond idealized portrayals of unity to explore the dynamics of estrangement, disconnection, and failure. While male friendship has often been celebrated as a cornerstone of democratic ideals, this study introduces the concept of “alienating intimacy.” This paradoxical form of attachment emphasizes emotional distance and difference, challenging conventional notions of intimacy and communion. Through the works of Henry David Thoreau, Nathaniel Hawthorne, Herman Melville, and Walt Whitman, I argue that these authors use male friendship to interrogate the tensions between intimacy and alienation, extending these dynamics to the author-reader relationship.The first chapter examines Thoreau’s A Week on the Concord and Merrimack Rivers, connecting his failed contemporary relationships to a yearning for an ideal future reader. By situating his vision of friendship within a broader temporal framework, the chapter demonstrates how Thoreau anticipates a distant, sympathetic readership. The second chapter explores Hawthorne’s ambivalence toward intimacy in The Scarlet Letter and his prefaces, where he resists reader transparency. This resistance mirrors the failed relationships between Dimmesdale and Chillingworth, with Hawthorne challenging traditional ideals of sympathy by portraying friendship as inherently isolating and hostile. The third chapter investigates betrayal and estrangement in Melville’s “Bartleby, the Scrivener” and The Confidence-Man. The failures of these relationships reflect Melville’s anxieties about his readers, presenting friendship as both disconnected and paradoxically intimate. The final chapter analyzes Whitman’s poetics of impersonal intimacy in Leaves of Grass. Through themes of contagion, decomposition, and sympathy, Whitman reimagines intimacy as a radical, boundary-transcending force. By presenting various aspects of “alienating intimacy,” this dissertation reconsiders the dynamics of male friendship and the author-reader relationship, emphasizing negativity and disconnection as central to their representation. This framework deepens contemporary theories of intimacy and offers fresh perspectives on nineteenth-century American literature
Design methods for cost-effective teams of mobile robots in uncertain terrain
No full textThesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 59-62).Conducting planetary exploration missions with mobile robots is expensive, with costs ranging from hundreds of millions to billions of dollars. Developing reliable robots to work remotely on rough, uncertain terrain is imperative for these missions. One potential tactic for improving the cost-effectiveness of these missions is to distribute the mass allowance for the mission over a team of smaller robots, rather than using a single robot. However, there is limited work on determining the size and design for a team of robots to provide the best overall performance when operating on hazardous terrain. This thesis develops a framework for designing mass-restricted, homogenous teams of mobile robots that will operate in a region with uncertain terrain conditions. The framework is built around three models: a four-wheeled robot model, a probabilistic model of terrain hazards, and a robot-terrain interaction model. The models are formulated into an optimization problem that can be used to determine the best design for a team of robots based on the team's combined equivalent straight-line velocity (CESLV), a novel measure of mission performance. CESLV is an effective measure of mission performance for both predetermined (static) mission plans and dynamic mission plans, where observations made by the robots can change the future mission tasks. A graphical user interface (GUI) is also presented which allows a designer to explore the design tradespace for the team of robots while considering important factors that are not captured by the models. In a case study of a Mars exploration mission, a team of robots provides superior performance to a single robot. A sensitivity analysis shows that the optimal size of the robot team is robust to inaccuracy in the terrain conditions. Additionally, the tradespace UI captures a trend in robot team design that would have otherwise gone unnoticed.by Nathaniel Steven Michaluk.S.M
A study of university timetabling that blends graph coloring with the satisfaction of various essential and preferential conditions
No full textConstructing a satisfactory conflict-free semester-long timetable of courses and creating a similarly satisfactory conflict-free timetable for end-of-semester final examinations are two closely related and often difficult problems that colleges and universities face each semester.
We discuss the relevance of such timetabling problems as a natural and practical application of graph coloring, and develop a mathematical and computational model for solving university timetabling problems using techniques of graph coloring that incorporates the satisfaction of both "essential" timetabling conditions (i.e., conditions or constraints that must be satisfied in order to produce a legal or feasible timetable) as well as suggested "preferential" timetabling conditions (i.e., additional conditions or constraints that need not necessarily be satisfied to produce a legal or legitimate timetable, but if satisfied may very well produce a more "acceptable" timetable for students and/or faculty members). We discuss in detail the step-by-step process that is taken to implement our timetabling-by-graph-coloring procedure, from the assembling of university course data, to creating a course conflict graph based on the assembled data, to coloring the conflict graph, to transforming this coloring to a conflict-free timetable, to finally assigning courses to classrooms. Once a conflict-free timetable of courses has been constructed, we present ways in which such a course timetable for a particular semester can be used to construct a conflict-free timetable of final examinations. Our model also considers a number of sociological scheduling concerns and preferences addressed by university registrars, faculty, staff, and students. Computational results, obtained by the author using actual data provided by Rice University and the University of St. Thomas, are documented
- …
