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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.
211

Analysis of Aircraft Emissions Based on Flight Trajectory : ATR 72-500 trajectory and emission study

Forsberg, Gustav, Sundberg, Carl-Michael January 2022 (has links)
Emissions related to aviation have during the last decades become an important topic of discussion. Besides carbon dioxide ($CO_2$) which is the major pollutant from air travel, other gas emissions such as hydrocarbons ($HC$), nitrogen oxides ($NO_x$), carbon monoxide ($CO$) and sulfur oxides ($SO_x$) also need to be investigated. The work within this field has traditionally been challenged by the fact that aircraft emission calculations often required engine proprietary data which usually is difficult to obtain. However, in recent years other methods have been developed and this report investigates one such method, namely The Boeing Fuel Flow Method 2. The analysis is carried out on an ATR 72-500 turboprop aircraft flying at $13000$ feet from Visby to Bromma, Sweden. The method uses continuous data of fuel flow and altitude together with estimated emission index data at sea level for the specific engine to estimate the amount of emissions emitted during the flight. From this it was possible to determine the levels of $HC$,$NO_x$,$CO$, $CO_2$ and $SO_x$ emitted during the different stages of flight. There was a clear trend that $HC$ and $CO$ emissions were the highest at low fuel flow levels, i.e. at low power, while $NO_x$ increased with increasing fuel flow. Emission levels of $CO_2$ and $SO_x$ were found to be proportional to fuel flow. In addition, two alternative trajectories at $10000$ and $24000$ feet were studied. When comparing the $10000$ feet route with the original $13000$ feet route the the level of $NO_x$, $CO_2$ and $SO_x$ were unaffected while $HC$ and $CO$ decreased as the period of high fuel flow were shortened. In the $24000$ feet route the levels of $HC$, $CO$ and $SO_x$ were unaffected while the level of $CO_2$ and $NO_x$ decreased. This decrease can be explained by the lowered fuel flow rate as air resistance is significantly lower at $24000$ feet compared to $13000$ feet.
212

ACOUSTICALLY AIDED COALESCENCE OF DROPLETS IN AQUEOUS EMULSIONS

Pangu, Gautam D. 27 February 2006 (has links)
No description available.
213

OPTIMISM/PESSIMISM AS A MEDIATOR OF SOCIAL STRUCTURAL DISPARITIES EFFECTS ON PHYSICAL HEALTH AND PSYCHOLOGICAL WELL-BEING: A LONGITUDINAL STUDY OF HOSPITALIZED ELDERS

Burant, Christopher J. 13 June 2006 (has links)
No description available.
214

Biomechanics of spore discharge in the Basidiomycota

Stolze-Rybczynski, Jessica L. 12 August 2009 (has links)
No description available.
215

Logarithmic and Exponential Transients in GNSS Trajectory Models as Indicators of Dominant Processes in Post-Seismic Deformation

Sobrero, Franco Sebastian 08 October 2018 (has links)
No description available.
216

Urban Transportation Analysis Using Taxi Trajectory and Weather Data

Tang, Hui 15 December 2016 (has links)
No description available.
217

Nonlinear Tracking by Trajectory Regulation Control using Backstepping Method

Cooper, David 07 October 2005 (has links)
No description available.
218

Robust control via higher order trajectory sensitivity minimization

Chopra, Avnish January 1994 (has links)
No description available.
219

Detection, location, and trajectory tracing of moving objects in the real world two-dimensional images

Reza, Hasnain January 1988 (has links)
No description available.
220

Trajectories of Headache Disability Treatment Response: Psychosocial and Clinical Correlates

Lewis, Kristin N. January 2009 (has links)
No description available.

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