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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.
1

Predicting fleet-vehicle energy consumption with trip segmentation

Umanetz, Autumn 26 April 2021 (has links)
This study proposes a data-driven model for prediction of the energy consumption of fleet vehicles in various missions, by characterization as the linear combination of a small set of exemplar travel segments. The model was constructed with reference to a heterogenous study group of 29 light municipal fleet vehicles, each performing a single mission, and each equipped with a commercial OBD2/GPS logger. The logger data was cleaned and segmented into 3-minute periods, each with 10 derived kinetic features and a power feature. These segments were used to define three essential model components as follows: The segments were clustered into six exemplar travel types (called "eigentrips" for brevity) Each vehicle was defined by a vector of its average power in each eigentrip Each mission was defined by a vector of annual seconds spent in each eigentrip 10% of the eigentrip-labelled segments were selected into a training corpus (representing historical observations), with the remainder held back for testing (representing future operations to be predicted). A Light Gradient Boost Machine (LGBM) classifier was trained to predict the eigentrip labels with sole reference to the kinetic features, i.e., excluding the power observation. The classifier was applied to the held-back test data, and the vehicle's characteristic power values applied, resulting in an energy consumption prediction for each test segment. The predictions were then summed for each whole-study mission profile, and compared to the logger-derived estimate of actual energy consumption, exhibiting a mean absolute error of 9.4%. To show the technique's predictive value, this was compared to prediction with published L/100km figures, which had an error of 22%. To show the level of avoidable error, it was compared with an LGBM direct regression model (distinct from the LGBM classifier) which reduced prediction error to 3.7%. / Graduate
2

Tradition Adrift: The History and Development of the Blessing of the Fleet in Stonington, Connecticut, 1950-2007

Menno, Justin James 22 August 2011 (has links)
No description available.
3

None

WANG, TSUNG-YU 15 July 2002 (has links)
None
4

United States navy fleet problems and the development of carrier aviation, 1929-1933

Wadle, Ryan David 01 November 2005 (has links)
The U.S. Navy first took official notice of aviation in 1910, but its development of carrier aviation lagged behind Great Britain??s until the 1920s. The first American aircraft carrier, the Langley, commissioned in 1919, provided the Navy with a valuable platform to explore the potential uses of carrier aviation, but was usually limited to scouting and fleet air defense in the U.S. Navy??s annual interwar exercises called fleet problems. This began to change in 1929 with the introduction of the carriers Lexington and Saratoga in Fleet Problem IX. After this exercise, which included a raid by aircraft from the Saratoga that ??destroyed?? the Pacific side of the Panama Canal, the carriers were assigned a wider variety of roles over the next five years of exercises. During this time, the carriers gained their independence from the battle line, which the smaller and slower Langley had been unable to do. Reflecting the advanced capabilities of the new carriers, the fleet problems conducted during Admiral William Veazie Pratt??s tenure as Chief of Naval Operations, 1930-1933, began to test the employment of the new carriers as the centerpiece of one of the opposing fleets within the exercises. The Lexington and Saratoga were used offensively during these exercises, employing their aircraft to sink surface ships, though not battleships, and successfully strike targets ashore. The carriers became successful in spite of the unreliability of early 1930s carrier aircraft, particularly the torpedo bombers, that could carry heavy payloads. Lessons learned from the Lexington and Saratoga Fleet Problems IX through XIV influenced the design of the next generation of American aircraft carriers, the Yorktownclass, which were authorized in 1933. These new carriers were faster and much larger than the carrier Ranger, commissioned in 1934 and designed before the Lexington and Saratoga began participating in the exercises. Features incorporated into the Yorktownclass based on operational experience included the reduced need for large surface batteries because of the use of escort vessels, the emphasis of armoring against shellfire over aerial bombs and torpedoes, and the capability to launch large numbers of aircraft quickly.
5

Enhancement of Civil Reserve Air Fleet an alternative for bridging the airlift gap /

Palmby, William G. 23 March 1998 (has links)
Thesis (M.M.A.S.)--School of Advanced Airpower Studies, 1995. / Subject: This study examines whether a revival of the CRAF enhancement program is feasible and if it could be developed into a viable program for addressing AMC's airlift shortfall problem. Cover page date: June 1995. Vita. Includes bibliographical references.
6

A transport economic appraisal of a methodology to calculate maintenance contract rates for vehicle fleets

Carstens, Stephanus Christiaan 21 November 2011 (has links)
D.Phil.
7

Projection of PM2.5, BC, NOx and VOCs from the Future Vehicle Fleet: Impact of Alternative Vehicle Penetration Versus Continual Reductions in Emissions from Traditional Vehicles

January 2020 (has links)
abstract: Mobile sources emit a number of different gases including nitrogen oxides (NOx) and volatile organic compounds (VOCs) as well as particulate matter (PM10, PM2.5). As a result, mobile sources are major contributors to urban air pollution and can be the dominant source of some local air pollution problems. In general, mobile sources are divided into two categories: on-road mobile sources and non-road mobile sources. In Maricopa County, the Maricopa County Air Quality Department prepares inventories of all local sources [11], [12]. These inventories report that for Maricopa County, on-road mobile sources emit about 23% of total PM2.5 annually, 58% of the total NOx, and 8% of the total VOCs. To understand how future changes how vehicles might impact local air quality, this work focuses on comparing current inventories of PM2.5, black carbon (BC), NOx, and VOCs to what may be expected emissions in future years based on different scenarios of penetration of hybrid gas-electric vehicles (HEV) and electric vehicles (EV) as well as continued reduction in emissions from conventional internal combustion (IC) vehicles. A range of scenarios has been developed as part of this thesis based on literature reports [6], [8], air quality improvement plan documentation [5], projected vehicle sales and registration [3], [4], as well as using EPA’s Motor Vehicle Emission Simulator (MOVES) [9]. Thus, these created scenarios can be used to evaluate what factors will make the most significant difference in improving local air quality through reduced emissions of PM2.5, BC, NOx and VOCs in the future. Specifically, the impact of a greater fraction of cleaner alternative vehicles such as hybrid-electric and electric vehicles will be compared to the impact of continual reductions in emissions from traditional internal combustion vehicles to reducing urban air pollution emissions in Maricopa County. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2020
8

Fleet-Based LCA: Comparative CO2 Emission Burden of Aluminum and Steel Fleets

Kirchain, Randy 26 June 2002 (has links)
No Abstract Provided
9

Corporate responsibility, marketing, and reputation : a stakeholder approach for sustainable car fleet management

Vogt, Roland January 2014 (has links)
Corporate responsibility is increasingly involved in corporate reputation, and so, in the economic success of a company. Car fleet operating companies are exposed to criticism and, as a direct result of this many corporate protagonists responsible for the operation of car fleets are developing measures to decrease CO2 emissions and fuel consumption. A second trend is the increasing usage of image-generating marketing actions in the worldwide ‘information society’. For various reasons, these image campaigns do not always lead to the expected improvements in corporate reputation. The crucial question is, how do these marketing actions, in the name of corporate social responsibility, relate to corporate reputation? The objective of this research is to establish rules for these relationships and to derive a new stakeholder approach to optimise corporate reputation regarding car fleet management marketing. First of all this study examines theoretical evidence in preparation for further empirical studies on the behaviour of sustainable car fleet management. With this in mind, the thesis looks at empirical evidence about the factors deemed necessary for successful responsible car fleet operation and its marketing. After conducting an online survey with more than 300 respondents, a multiple-embedded-case study with three cases, six supplementary cases, and several stakeholders represents the main part of this work. As a result, this work depicts, through three models, and via a new stakeholder approach (a combination of the three), the relationships of certain main types of firm with main types of fleet as well as the main types of marketing to support corporate reputation. Unexpected findings regarding the suitable intensity of communication to internal and external stakeholders have emerged. This approach successfully supports the design of sustainable car fleet management and a suitable arrangement of the marketing approach.
10

Optimalizace vozového parku pomocí systému Positrex / Fleet optimization using the PosiTrex system.

Kazakova, Yauheniya January 2010 (has links)
The thesis aims to describe and evaluate one of the systems for the fleet monitoring, which is available on the Czech market.The thesis consists of two parts. The first part describes the Global Positioning System GPS and fleet management.The second part discusses of an international monitoring system PosiTrex whose provider is Level Ltd. Interpretation includes a performance of the company, a description of the benefits system and describes the communication units.

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