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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.
11

Model Predictive Adaptive Cruise Control with Consideration of Comfort and Energy Savings

Ryan, Timothy Patrick 09 June 2021 (has links)
The Hybrid Electric Vehicle Team (HEVT) of Virginia Tech is partaking in the 4-Year EcoCar Mobility Challenge organized by Argonne National Labs. The objective of this competition is to modify a stock 2019 traditional internal combustion engine Chevrolet Blazer and to transform the vehicle into a P4 hybrid. Due to the P4 Hybrid architecture, the HEVT vehicle has an internal combustion engine on the front axle and an electric motor on the rear axle. The goal of this competition is to create a vehicle that achieves better fuel economy and increases customer appeal. The general target market of hybrids is smaller vehicles. As a midsize sport utility vehicle (SUV), the Blazer offers a larger vehicle with the perk of better fuel economy. In the competition, the vehicle is assessed on the ability to integrate advanced vehicle technology, improve consumer appeal, and provide comfort for the passenger. The research of this paper is centered around the design of a full range longitudinal Adaptive Cruise Control (ACC) algorithm. Initially, research is conducted on various linear and nonlinear control strategies that provide the necessary functionality. Based on the ability to predict future time instances in an optimal method, the Model Predictive Control (MPC) algorithm is chosen and combined with other standard control strategies to create an ACC system. The main objective of this research is the implementation of Adaptive Cruise Control features that provide comfort and energy savings to the rider while maintaining safety as the priority. Rider comfort is achieved by placing constraints on acceleration and jerk. Lastly, a proper energy analysis is conducted to showcase the potential energy savings with the implementation of the Adaptive Cruise Control system. This implementation includes tuning the algorithm so that the best energy consumption at the wheel is achieved without compromising vehicle safety. The scope of this paper expands on current knowledge of Adaptive Cruise Control by using a simplified nonlinear vehicle system model in MATLAB to simulate different conditions. For each condition, comfort and energy consumption are analyzed. The city 505 simulation of a traditional ACC system show a 14% or 42 Wh/mi reduction in energy at the wheel. The city 505 simulation of the environmentally friendly ACC system show a 29% or 88 Wh/mi reduction in energy at the wheel. Furthermore, these simulations confirm that maximum acceleration and jerk are bounded. Specifically, peak jerk is reduced by 90% or 8 m/s3 during a jerky US06 drive cycle. The main objective of this analysis is to demonstrate that with proper implementation, this ACC system effectively reduces tractive energy consumption while improving rider comfort for any vehicle. / Master of Science / The Hybrid Electric Vehicle Team (HEVT) of Virginia Tech is partaking in the 4-Year EcoCar Mobility Challenge organized by Argonne National Labs. The objective of this competition is to modify a stock 2019 Chevrolet Blazer into a hybrid. This modification is accomplished by creating a vehicle that burns less gasoline and increases customer appeal. The general target market of hybrids is smaller vehicles. As a midsize sport utility vehicle (SUV), the Blazer offers a larger vehicle with the perk of better fuel economy. In the competition, the vehicle is assessed on the ability to integrate advanced technology, improve consumer appeal, and provide comfort for the passenger. The research of this paper is centered around the design of Adaptive Cruise Control (ACC). Initially, research is conducted on various control strategies that provide the necessary functionality. A controller that predicts future events is selected for the Adaptive Cruise Control. The main objective of this research is the implementation of Adaptive Cruise Control features that provide comfort and energy consumption savings to the rider while maintaining safety as the priority. Rider comfort is achieved by creating a smoother ride. Lastly, a proper energy analysis showcases the potential energy savings with the implementation of the Adaptive Cruise Control system. The scope of this paper expands on current knowledge of Adaptive Cruise Control by using a simplified vehicle model to simulate different conditions. The city simulations of a traditional ACC system show a 14% reduction in energy at the wheel. City simulations of the environmentally friendly Adaptive Cruise Controller show a 29% reduction in energy. Both of these simulations allow for comfortable ride. Specifically, maximum car jerk is reduced by 90%. The main objective of this analysis is to demonstrate that with proper implementation, this ACC system effectively reduces energy consumption at the wheel while improving rider comfort.
12

The naval airship and the revolution at sea.

Shelby, James Richard. January 1990 (has links) (PDF)
Thesis (M.S. in Operations Research)--Naval Postgraduate School, September 1990. / Thesis Advisor(s): Hughes, Wayne P. Second Reader: Jackson, John E. "September 1990." Description based on title screen as viewed on December 21, 2009. DTIC Descriptor(s): Airships, Military Operations, Ships, Sizes(Dimensions), Naval Vessels, Ocean Surface, Models, Threats, Navy, Teams(Personnel), Costs, Surfaces, Military Force Levels, Area Defense, Fire Control Systems, Battle Group Level Organizations, Extrapolation, Surface Launched. DTIC Identifier(s): Airship, Fire Control Systems, Blimp, Lighter-than-air, SLAT Missile, Anti Ship Cruise Missile(ASCM), Over-the-horizon Targeting, Theses. Author(s) subject terms: Airship, Blimp, Lighter-than Air, SLAT Missile, Anti-ship Cruise Missile (ASCM), Over-the-Horizon Targeting. Includes bibliographical references (p. 136-138). Also available in print.
13

Die geskiedenis van Projek Taurus en die Missielbootprojekte, 1968-1987

Potgieter, Theodorus Daniël 12 August 2014 (has links)
M.A. (History) / Please refer to full text to view abstract
14

A preliminary study of the characteristics of noisy vehicles under cruising conditions – results of roadside measurements

Watts, Gregory R. 03 1900 (has links)
Yes / In the past it has been found that the maximum pass-by noise for the most noisy of vehicles can be 6-8 dB(A) above the average for the sample. It is therefore useful to consider the types of vehicle that make excessive noise and their condition and to reach some conclusions on how best to reduce the problem. Measurements of maximum noise, pass-by speed together with video footage were taken on a busy dual carriageway road (A34) in the UK carrying a high percentage of heavy vehicles. The intention was to collect sufficient information on light, medium heavy and heavy vehicles to enable typical characteristics of noisy vehicles to be identified. Peak noise levels produced by vehicles under normal operating conditions of steady speed were recorded and not of vehicle being driven in an aggressive manner e.g. under harsh acceleration. This paper reports on the characteristics of excessively noisy vehicles that were identified under these cruising conditions in free flow traffic conditions. / The work described in this report was carried out in the Noise and Vibration Team of TRL Limited under funding from the Transport Research Foundation.
15

Visual collision avoidance

Matthews, Neil David January 1999 (has links)
No description available.
16

Optimizing Ground Based Air Defense in support of homeland defense the cruise missile threat

Soria, Javier C. 12 1900 (has links)
Since the attacks of September 11th, 2001 involving commercial aircraft used as missiles to attack critical assets located within the United States, the U.S has worked diligently to enhance its military air defense posture. Air defense of critical U.S. assets and National Special Security Events (NSSE) have been enhanced by adding static and proposed deployable Ground Based Air Defense (GBAD) systems designed to provide a [beta]last line[gamma] of defense from air attacks over U.S. soil. Currently this last line of defense is incorporated with the air and maritime military air defense forces providing a [beta]defense in depth[gamma] over critical assets, but does not support the air and maritime air defense over broader ranges of U.S. soil where critical assets do not exist. As the U.S. continues to enhance its air defense posture around critical assets and high priority events against terrorist attacks from the air, it is reasonable to assume that the terrorists may adjust their strategy for air attacks. The terrorists may deem it more beneficial to attack targets which lack a last line defense. It is therefore critical to examine new means and methods to provide GBAD in areas which may be determined to be less lucrative targets. In addition to the proposed alternate terrorist strategy, it is also reasonable to assume that increased security measures in the Transportation Security Administration (TSA) will deter the terrorists from attempting another hijacking event; thus forcing them to seek other means of attack. Cruise missiles (CM) are a cheap and effective means of causing limited destruction. Cruise missiles can be programmed to maneuver and operate at various altitudes and are small enough to be transported with little to no visibility. A cruise missile in the wrong hands could find its way to within miles of the U.S. borders and coastlines. If launched; a cruise missile could engage random targets throughout the U.S., such as malls or schools, and cause a major upset to our national security. Therefore, a defense system should be established which incorporates GBAD that is capable of engaging the CM threat with little to no notice, over the entire U.S. border and coastal regions.
17

Cruise industry - analýza, postavenie a potenciál lodných zájazdov v oblasti cestovného ruchu / Cruise industry - analysis, role and potential of cruises in the tourism industry

Kocún, Jozef January 2010 (has links)
This final thesis deals with cruises and cruise line industry in general. The first chapter describes cruises and highlights their particulars. The second chapter analyzes all the available statistics (secondary data) that depict the role of cruise line industry in the field of tourism (fleet, cruise lines, passengers, destinations, ports, economic impact). As for the primary research, I created a questionnaire to determine the requirements of respondents for an ideal cruise. I have conducted a mystery shopping, together with a personal interview with an employee of an travel agent's to analyze the state of the market and the sale of cruises both in Czech and Slovak Republic. The last chapter discusses the current and future trends in the cruise industry. The results of this thesis confirm the hypothesis that Czech Republic and Slovakia have the potential to attract customers and bring potential customers.
18

Taiwanese cruisers in North America an empirical analysis of their motivations, involvement, and satisfaction /

Huang, Taiyi. Josiam, Bharath Morapakkam, January 2009 (has links)
Thesis (M.S.)--University of North Texas, August, 2009. / Title from title page display. Includes bibliographical references.
19

Cruise Tourism in Bar Harbor, Maine: An Analysis of Likelihood of Passenger Return and Passenger Expenditures in Port

Lynch, Colleen P. January 2004 (has links) (PDF)
No description available.
20

The management of human resources on cruise ships : the realities of the roles and relations of the HR function

Schlingemann, Thomas January 2016 (has links)
This thesis aims to contribute to a deeper understanding of human resource management (HRM) within cruise ship organizations. The cruise ship industry is one of the fastest developing sectors within the tourism industry. Therefore, it should come as little surprise that the demand for seafaring human resources has also grown. Assuming that effective management of crew members is key to the effective operation of cruise ships, the specifics and challenges for HRM in this particular organisational context are identified and analysed as well as the realities of the roles and relations of the shipboard HR function examined. The present study is original in its theoretical approach, as it brings two approaches together which obviously are not linked. Ulrich’s model talks about roles and the study used aspects of this framework in terms of the position of HRM. Goffman’s concept of total institutions was also consulted in order to frame internal business-specific conditions and social relations. The combination of both approaches allows for the examination of HR roles and professional relations in a much more detailed and contextualised manner. The cruise industry is acknowledged as being under-researched, and this is all the more true for research on HRM in this specific sector. Therefore, the nature of the research in this study is empirical and framed within an explorative approach. The analysis is based on a single case study within one cruise ship owner company, in which 23 semi-structured interviews were performed; there is also the use of ethnographic field notes recorded during a three-month assignment on one of the company’s cruise ships. The thesis contributes to the existing literature in three ways. Firstly, the research analyses shoreside HR and how it is coping with various business-specific challenges, i.e. high growth rates, a high demand for new cruise ship employees, high turnover rates of crew members and a distinctive context of ethnic and national diversity. The analysis reveals that the HRM approach of the cruise shipowner company could be characterised as generally reactive and short-term in focus, a pure strategic orientation is absent. Secondly, the thesis examines the content of shipboard HR work. The study reveals that the main focus of the shipboard HR function is on tactical HR work, especially training and development, employee relations, and advisory role in relation to shipboard leaders. The shipboard HR role includes HR activities that are not usually provided by HR business partners, such as the facilitation of training. This and the intense liaison between the shipboard HR function and its shoreside HR partners make shipboard HR work somewhat unique. Whereas a huge amount of transactional HR work does not necessarily add value to the business, strategic HR work is practically non-existent on cruise ships. Finally, the thesis examines the realities of HR roles and relations on board cruise ships. The analysis demonstrated that HRM on board cruise ships can currently be summarised as reactive and short-term in focus, and the strategic partner role is practically non-existent. It is more a series of functions with different stakeholders contributing to it in a variety of ways and with overlap in terms of task executions. This shared nature of HR adds complexity to the HRM approach. Furthermore, strong influential links from shoreside HR were identified, which undermines the ability of the shipboard HR function to become a stronger partner of the business. Nevertheless, the analysis revealed the potential in this specific sector for enhancements and for the further development of HRM on cruise ships.

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