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Technologie automatického řízení civilního letadla po trajektorii přibližování na přistání / Technology of aircraft automatic flight control along an approach trajectoryKočiš, Martin January 2020 (has links)
This diploma thesis is focused to systems used for automatic control of civil aircraft along an precision approach trajectory. It describes precision approach systems used in the past and their evolutional steps leading to their current and future configuration. The thesis does not put the goal to be a detailed study but to be a publication providing to pilots and students of Aeronautical traffic the introduction to the field of precision approach systems in context to another fields of aeronautical traffic, describing its current status and infer its further development.
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An Informal Transit System Hiding in Plain Sight: Brooklyn's Dollar Vans and Transportation Planning and Policy in New York CityGoldwyn, Eric Louis January 2017 (has links)
New York’s transit system serves millions of riders each day; the local newspapers complain about the lack of funding for infrastructure projects; and the City Council regularly hosts hearings about Bus Rapid Transit, bike-share, road safety, e-hail taxis, and gondolas. Transportation issues matter to New Yorkers, but these debates, at the policy level, often focus on technology, budgets, and regulations rather than the needs and experiences of passengers. This focus on “technical” matters allows planners and politicians to confine transportation debates to the realm of experts rather than engage the broader public in them.
The failure to address the needs of passengers in Brooklyn and Queens has led to the development of dollar vans. Dollar vans are hybrid bus-taxis, also known as jitneys, that provide vital transportation links to more than 120,000 riders per day and operate beyond the control of the formal transit system governed by the Metropolitan Transportation Authority (MTA). While this ridership pales in comparison to the daily ridership on the subway or bus, it does rival bus ridership in cities like Dallas and Milwaukee and dwarfs the 50,000 peak ridership achieved by Citi Bike, New York’s celebrated bike-share system. More important, the durability of the vans reveals the failures of the existing formal system to serve all New Yorkers.
I argue that this failure is important for three reasons. First, the vans respond to a geographically specific problem: adequate access to inadequate service. The vans thrive in busy transit corridors where MTA-owned buses come too infrequently, are overcrowded, or are regularly stuck in traffic. On these busy routes, the vans provide a more reliable ride and alternative for transit-dependent populations looking to bypass the faltering bus system. Second, regulations fail to reflect daily practice. This gap between practice and policy leaves van operators and passengers in an awkward limbo that criminalizes an industry and jeopardizes the mobility of entire neighborhoods. Third, since the vans operate outside of the formal system, traditional metrics, such as ridership, travel time, vehicle revenue miles, etc., are not collected and compared against the metrics of other modes operated by the MTA. As long as the vans remain an unknown quantity, it is impossible for the City and State to serve transit-dependent populations in Brooklyn and Queens.
In this dissertation, I use a mixed-methods research design to probe the world of the vans and argue that continued regulatory uncertainty, long the friend of the vans, has the potential to upend them as development pressures and capital investment in Central Brooklyn intensifies.
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An Analysis of Household Vehicle Ownership and Utilization Patterns in the United States Using the 2001 National Household Travel SurveyPinjari, Abdul Rawoof 01 April 2004 (has links)
Vehicle ownership and utilization have a profound influence on activity-travel patterns of individuals, vehicle emissions, fuel consumption, highway capacity, congestion and traffic safety. The influence could be further skewed by the diversity of the vehicle fleet. This thesis presents a detailed analysis of the 2001 National Household Travel Survey data to understand the vehicle ownership patterns, fleet mix, allocation and utilization in the context of household and person socio-demographic characteristics. Along with a rich descriptive analysis, models of vehicle ownership and utilization are estimated to distinguish four vehicle types; cars, SUVs (sport utility vehicles), vans and pickup trucks based on their ownership by households and utilization patterns by household members. The primary driver level vehicle utilization analysis provides insights into the extent of allocation of a vehicle to a single person. In addition to confirming many perceptions about the ownership, acquisition and utilization patterns of different types of vehicles, this analysis brings out some subtle differences and similarities among the vehicle types. The analysis results indicate a greater propensity to acquire and use larger vehicles such as minivans, sports utility vehicles and pickup trucks among certain socio-demographic segments of population. Increased ownership and use of vans and SUVs, and their usage as personal vehicles rather than just work vehicles warrants a need to revise vehicle type specific policies, transportation planning and control measures.
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Implications of Advanced Technologies on Rural DeliveryKaplan, Marcella Mina 24 May 2024 (has links)
This dissertation integrates the strengths of individual emergent delivery technologies with package characteristics, and rural community needs to meet the demand for equitable, accessible, and inclusive rural delivery that is also cost-effective. To find ways to meet the package delivery service needs in rural areas and to fill research gaps in rural package delivery modeling, this study introduced a novel model known as the Parallel Scheduling Vehicle Routing Problem (PSVRP) in an endeavor to revolutionize package delivery by enhancing its efficiency, accessibility, and cost-effectiveness. The PSVRP represents a state-of-the-art approach to vehicle routing problems, incorporating a diversified fleet of innovative delivery modes. The multi-modal fleet of electric vans, ADVs, drones, and truck-drone systems works in unison to minimize operational costs in various settings. A solution methodology that implemented the Adaptive Large Neighborhood Search (ALNS) algorithm was designed to solve the PSVRP in this research to produce optimal or near-optimal solutions.
A variety of scenarios in a rural setting that include different quantities of customers to deliver to and different package weights are tested to evaluate if a multi-modal fleet of electric vans, ADVs, drones, and truck-drone systems can provide cost-effective, low emissions, and efficient rural delivery services from local stores. Different fleet combinations are compared to demonstrate the best combined fleet for rural package delivery. It was found that implementation of electric vans, ADVs, drones, and truck-drone systems does decrease rural package delivery cost, but it does not yet decrease cost enough for the return on investment to be high enough for industry to implement the technology. Additionally, it was found that electric technologies do significantly decrease emissions of package delivery in rural areas. However, without a carbon tax or regulation mandating reduced carbon emissions, it is unlikely that the delivery industry will quickly embrace these new delivery modes.
This dissertation not only advances academic understanding and practical applications in vehicle routing problems but also contributes to social equity by researching methods to improve delivery services in underserved rural communities. The PSVRP model could benefit transportation professionals considering technology-enabled rural delivery, developing rural delivery plans, looking for cost-effective rural delivery solutions, implementing a heterogeneous fleet to optimize rural delivery, or planning to reduce rural delivery emissions. It is anticipated that these innovations will spur further research and investment into rural delivery optimization, fostering a more inclusive and accessible package delivery service landscape. / Doctor of Philosophy / This dissertation integrates the strengths of individual emergent delivery technologies with package characteristics, and rural community needs to meet the demand for equitable, accessible, and inclusive rural delivery that is also cost-effective. To find ways to meet the package delivery service needs in rural areas and to fill research gaps in rural package delivery modeling, this study introduced a novel model known as the Parallel Scheduling Vehicle Routing Problem (PSVRP) in an endeavor to revolutionize package delivery by enhancing its efficiency, accessibility, and cost-effectiveness. The PSVRP represents a state-of-the-art approach to vehicle routing problems, incorporating a diversified fleet of innovative delivery modes. The multi-modal fleet of electric vans, ADVs, drones, and truck-drone systems works in unison to minimize operational costs in various settings. A solution methodology that implemented the Adaptive Large Neighborhood Search (ALNS) algorithm was designed to solve the PSVRP in this research to produce optimal or near-optimal solutions.
A variety of scenarios in a rural setting that include different quantities of customers to deliver to and different package weights are tested to evaluate if a multi-modal fleet of electric vans, ADVs, drones, and truck-drone systems can provide cost-effective, low emissions, and efficient rural delivery services from local stores. Different fleet combinations are compared to demonstrate the best combined fleet for rural package delivery. It was found that implementation of electric vans, ADVs, drones, and truck-drone systems does decrease rural package delivery cost, but it does not yet decrease cost enough for the return on investment to be high enough for industry to implement the technology. Additionally, it was found that electric technologies do significantly decrease emissions of package delivery in rural areas. However, without a carbon tax or regulation mandating reduced carbon emissions, it is unlikely that the delivery industry will quickly embrace these new delivery modes.
This dissertation not only advances academic understanding and practical applications in vehicle routing problems but also contributes to social equity by researching methods to improve delivery services in underserved rural communities. The PSVRP model could benefit transportation professionals considering technology-enabled rural delivery, developing rural delivery plans, looking for cost-effective rural delivery solutions, implementing a heterogeneous fleet to optimize rural delivery, or planning to reduce rural delivery emissions. It is anticipated that these innovations will spur further research and investment into rural delivery optimization, fostering a more inclusive and accessible package delivery service landscape.
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The Structural Suitability of Tensegrity Aircraft WingsMills, Austin Shelley 22 June 2020 (has links)
No description available.
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