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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
471

A History of Land Grants to Texas Railroads 1852 to 1882

Ramsey, Volney E. 08 1900 (has links)
This study examines the history of federal land grants given to railroads in Texas upon their admittance to the Union in the "Iron Horse Age" of Texas. Covering the rise of the land grant idea, the first period of special land grants, the period of the first general land grant act, the period of prohibition of land grants, and finally last of the land grant periods,
472

A Rhetorical Analysis of Robert M. La Follette's Address on the Hepburn Bill

Kleiber, Carolyn January 1963 (has links)
No description available.
473

Minefield, Railway, Temple: The Violent Making of Space and Time in Israel/Palestine

Elmakias, Zohar January 2024 (has links)
Israel’s spatial imaginary, as an unsettled project, is in constant negotiation, revision, and transmutation. At the heart of this dissertation is an ethnographic endeavor driven by a reading of the past, present, and future of political and religious struggles in Israel/Palestine through an analysis of actors, practices, and material palimpsests of three sites: a French Mandate building and former Syrian military base in the Golan Heights, turned into a boutique hotel by a security entrepreneur; the longed-for and imagined Third Temple in Jerusalem—today’s Temple Mount—a once marginal messianic scheme currently in revival; and the Jaffa Ottoman train station, reopened as a high-end shopping center and later as a light rail station. Through these sites, this dissertation asks how Israel understands itself vis-à-vis its narrative of a biblical past, its present ‘indigenous’ presence, and its vision or imaginaries of the future.
474

An Acute Sense of Place: The Songs of Norman Blake

Jutz, Thomas 01 December 2022 (has links)
American flat-picking guitarist, singer and songwriter Norman Blake holds legendary status among guitar players, bluegrass, and folk musicians. The aim of this research is to analyze the interaction of sense of place in Norman Blake’s songwriting. This research will explore the techniques Blake uses to create that acute sense of place. Elements of literary criticism, cultural geography, ethnomusicology, and sense of place studies, as well as historical background information on Northern Alabama and North Georgia will be employed to show how this particular region of Southeastern Appalachia has informed Blake’s songwriting. The research questions that I aim to answer are how a sense of place has influenced Norman Blake’s songwriting, how his writing has influenced other songwriters in the field of 20th century folk music, bluegrass, Americana, and country music, and what songwriting techniques Blake has employed to create an acute sense of place.
475

A Narrative Atlas of the Gunnison-Beckwith Survey for the Pacific Railroad, 1853-1854

Bentley, Elbie 21 September 2009 (has links)
No description available.
476

Switching Tracks: The Place of Railroads in an Era of Economic and Environmental Reform, 1966-80

Wollet, Benjamin W. 18 April 2012 (has links)
No description available.
477

A Proactive Approach to Train Control

Thurston, David Frank January 2012 (has links)
The main objective in optimizing train control is to eliminate the waste associated with classical design where train separation is determined through the use of "worst case" assumptions to calculate Safe Braking Distances that are invariant to the system. In fact, the worst case approach has been in place since the beginning of train control systems. Worst case takes the most conservative approach to the determination of train stopping distance, which is the basis for design and capacity of all train control systems. This leads to stopping distances that could be far more than actually required under the circumstances at the time the train is attempting to brake. A new train control system is proposed that utilizes information about the train and the conditions ahead to optimize and minimize the Safe Braking Distance. Two methods are proposed to reduce safe braking distance while maintaining an appropriate level of safety for the system. The first introduces a statistical method that quantifies a braking distance with various hazards levels and picks a level that meets the safety criteria of the system. The second method uses train mounted sensors to determine the adhesion level of the wheel and rail to determine the appropriate braking rate for the train under known circumstances. Combining these methods provides significant decreases in Safe Braking Distances for trains. A new train control system is utilized to take advantage of these features to increase overall system capacity. / Electrical and Computer Engineering
478

Risk Mitigation and Management Strategies for Routing Hazardous Materials over Railroad Network in Canada

Vaezi, Ali January 2018 (has links)
Railroad transportation of hazardous materials (hazmat) has grown significantly in recent years in Canada. Although rail is one of the safest modes for hazmat transport, the risk of catastrophic events such as the Lac Mégantic train disaster, does exist. In this thesis, we study a number of measures to manage and mitigate the risk associated with rail hazmat shipments. First, we propose a methodology that makes use of analytics to dis-aggregate national freight data to estimate hazmat traffic on rail-links and at rail-yards in Canada. Further, a focused analysis is conducted on crude oil rail shipments to develop long-term forecasts and evaluate the impact of proposed pipeline projects. Second, we present an emergency response planning problem, aimed at the effective and efficient response to rail hazmat incidents. A two-stage stochastic programming problem is solved over part of the Canadian railroad network, which provides recommendations on where to locate response facilities, and which equipment packages to stockpile at each facility. Finally, we study infrastructure investment as a strategy to mitigate the risk associated with rail hazmat shipments. This strategy is based on building new railway tracks to provide alternative routes to the riskiest parts of the network. Given the hierarchical relationship between the decisions made by regulatory agencies and railroad companies, a bilevel programming approach is used to identify the optimal set of infrastructure investment options given an allocated budget. Our computational experiments show that significant network-wide risk reduction is possible if hazardous shipments are routed using some of the proposed alternative rail tracks. / Thesis / Doctor of Philosophy (PhD)
479

Strategy in thin industries : essays in the social organization of industry

Lampel, Joseph January 1990 (has links)
No description available.
480

Application of Multifunctional Doppler LIDAR for Non-contact Track Speed, Distance, and Curvature Assessment

Munoz, Joshua 08 December 2015 (has links)
The primary focus of this research is evaluation of feasibility, applicability, and accuracy of Doppler Light Detection And Ranging (LIDAR) sensors as non-contact means for measuring track speed, distance traveled, and curvature. Speed histories, currently measured with a rotary, wheel-mounted encoder, serve a number of useful purposes, one significant use involving derailment investigations. Distance calculation provides a spatial reference system for operators to locate track sections of interest. Railroad curves, using an IMU to measure curvature, are monitored to maintain track infrastructure within regulations. Speed measured with high accuracy leads to high-fidelity distance and curvature data through utilization of processor clock rate and left-and right-rail speed differentials during curve navigation, respectively. Wheel-mounted encoders, or tachometers, provide a relatively low-resolution speed profile, exhibit increased noise with increasing speed, and are subject to the inertial behavior of the rail car which affects output data. The IMU used to measure curvature is dependent on acceleration and yaw rate sensitivity and experiences difficulty in low-speed conditions. Preliminary system tests onboard a 'Hy-Rail' utility vehicle capable of traveling on rail show speed capture is possible using the rails as the reference moving target and furthermore, obtaining speed profiles from both rails allows for the calculation of speed differentials in curves to estimate degrees curvature. Ground truth distance calibration and curve measurement were also carried out. Distance calibration involved placement of spatial landmarks detected by a sensor to synchronize distance measurements as a pre-processing procedure. Curvature ground truth measurements provided a reference system to confirm measurement results and observe alignment variation throughout a curve. Primary testing occurred onboard a track geometry rail car, measuring rail speed over substantial mileage in various weather conditions, providing high-accuracy data to further calculate distance and curvature along the test routes. Tests results indicate the LIDAR system measures speed at higher accuracy than the encoder, absent of noise influenced by increasing speed. Distance calculation is also high in accuracy, results showing high correlation with encoder and ground truth data. Finally, curvature calculation using speed data is shown to have good correlation with IMU measurements and a resolution capable of revealing localized track alignments. Further investigations involve a curve measurement algorithm and speed calibration method independent from external reference systems, namely encoder and ground truth data. The speed calibration results show a high correlation with speed data from the track geometry vehicle. It is recommended that the study be extended to provide assessment of the LIDAR's sensitivity to car body motion in order to better isolate the embedded behavior in the speed and curvature profiles. Furthermore, in the interest of progressing the system toward a commercially viable unit, methods for self-calibration and pre-processing to allow for fully independent operation is highly encouraged. / Ph. D.

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