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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.
171

Human skill maintenance in complex work environments : applications to extended spaceflight

Sauer, Juergen January 1997 (has links)
This thesis examines human performance under sub-optimal working conditions during work with complex and highly-automated process control systems. The operational context focuses on applications in extended spaceflight but the generic approach allows for generalisations beyond this target work environment The methodological approach is based on the use of a computerised multiple-task environment to carry out generic simulations of real work environments (micro-worlds) with a high level of ecological validity. For that purpose, a PC-based task. environment was developed to simulate the operation of a life support system in a spacecraft. This task environment has been used in lab-based experiments with trained participants from the student population and with real space crews during large-scale mission simulations. A series of six experiments was carried out (3lab and 3 field studies) to investigate the impact of different configurations of sub-optimal working conditions and unfavourable operator states, using the following independent variables: sleep deprivation, dialogue control, social isolation and confinement, training, noise, extended lay-off period and different types of system faults (corresponding to variations in workload). The task environment comprised up to five tasks, allowing for the observation of differential effects of the independent variables on different levels of cognitive activity. Dependent variables included primary task performance, secondary task performance, system control behaviour, information sampling behaviour, and subjective state measures. The findings suggested that primary performance was rarely affected, whereas certain secondary task measures and, notably, information sampling strategies appeared to be good indicators of changes in demand under the unfavourable conditions. The isolation and confinement experiments revealed no serious breakdown of performance among the crew but some indications of strain were observed. The use of two different training approaches displayed a very complex picture, with no method showing clear superiority over the other concerning performance, though there were differences in knowledge structure and system management behaviour. An important implication of the experimental work is that a broad methodological approach is needed in order to investigate the complex adjustment patterns displayed by individuals during the management of task demands under unfavourable conditions.
172

Investigation of Runway Incursion

Markne, Joakim, Ström, Carl January 2013 (has links)
Runway incursions (RWYI) are a daily phenomenon in the world and is a threat to safety. The severity of a RWYI can be high and it is a problem that is subject to improvements. The purpose of this report is to present the findings after an investigation of RWYI in general and what is being done to prevent it in Sweden. The main focus is to present the problem from an air traffic controller (ATCO) and pilot perspective. However, we are also presenting all the different stakeholders involved in the problem followed with associated risks and means to prevent a RWYI from happening. We also present technical aids and working methodology used today in air traffic control towers in Sweden and in addition some technology implemented abroad. Some suggested improvements that the stakeholders can take into consideration when developing their work to reduce the risk for a RWYI is also presented. The method used during the investigation has mainly been literature studies, interviews with different stakeholders and study visits to Bromma tower, Arlanda tower and SAAB/Linköping tower. We have found that the pilots and vehicle drivers are the most contributing stakeholders to a RWYI in Sweden. The investigation also shows that ATCOs and pilots share some opinions regarding risks but also improvements. Both ATCOs and pilots agree that weather with bad visibility, as well as darkness, is increasing the risk for an incident or accident to happen. Furthermore, complacency, fatigue and tiredness are also risks that are shared between ATCOs and pilots. We have also found that airports have different means to prevent a RWYI. At Arlanda, the ATC system is well developed with electronic equipment and stop bars at the taxiways, which is not the case for either Bromma or SAAB/Linköping airport. Even pilots in different airlines operate differently when about to enter a runway and there is no standard operating procedure (SOP) developed in all companies. Some of the suggested improvements are to implement stop-bars on every airport and that it should be mandatory to equip vehicles operating on the maneuvering area with maps.
173

Pricing of radar data

Linder, Martin, Nylin, Tobias January 2013 (has links)
In this thesis we examine the issue regarding pricing of radar data and surveillance to the operators of air navigation service (ANS) at the aerodromes in Sweden. The question of who should be responsible for providing radar data to the operators is being managed that results in if it should be LFV, as it is today, the government or another authority. This is being examined since LFV in 2010 lost its monopoly position in the terminal area in Sweden. LFV still has monopoly on the en route part, and thru the en route income finances the radar data to all operators in Sweden. Air traffic service units (ATS) receive the radar data without any compensation to LFV, this needs to be regulated and conditions and prerequisites are necessary to be implemented. Our supervisor at LFV, Anders Andersson, has been the primary source of information regarding the current situation, background for the problem and also provided relevant documents with proper information. Laws and regulations have been accessed via the Swedish Transport Agency’s website and scientific articles on monopolies and pricing in aviation and other markets have been used in order to compare earlier issues similar to ours. The literature studies combined with interviews with Anders Andersson are the foundations of the development of the pricing schemes. The result of the thesis is presented as three different pricing schemes where each one of them are presented in tables and analysed how it will affect the ATS. In the first pricing scheme the cost for maintenance is equally divided between all ATS, this means every ATS has to pay the same cost regardless size of the airport, number of movement and net sales. The second pricing scheme is based on number of landings per year and divides the ATS in three categories. This scheme increases the cost with concern to the number of landings, which results in the larger ATS are charged more than the smaller ATS. The final pricing scheme is divided in four categories and based on terminal control area (TMA) and requirements on surveillance service. This means the different categories are based on a combination of the median distance flown in TMA and the different requirements the ATS must provide surveillance service. This pricing scheme is a disadvantage for the military airports and the ATS with associated TMA. The conclusions that can be made are the Swedish Transport Agency needs to implement some distinct guidelines and regulations regarding how the pricing should be made, where the pricing schemes and analysis in this thesis could form the basis for future investigations.
174

The problem of registration and nationality of aircraft of international operating agencies and the I.C.A.O. Council's resolution on the problem /

Goreish, Ishaq Rasheed Sid Ahmed. January 1970 (has links)
No description available.
175

Clipping the Eagle's Wings: The Limiting of the Korean Air War, 1950-1953

Horky, Roger Karl 02 October 2013 (has links)
Purpose: This work examines the transition in aerial warfare that took place during the Korean War (1950-1953). Before the conflict, air power was conceived of primarily an instrument of unlimited, or total, warfare. Yet Korea, and all subsequent air wars, have been limited. The transitional nature of the Korean air war has not yet been adequately explored by historians. Methods: The story of this shift is presented in two parts, the first examining the doctrines of the United States Air Force (USAF) immediately before the Korean War, the second comparing them to the USAF’s actual campaigns in Korea. This focus on the USAF reflects both its status as the principal air service in Korea and its influence on the theories and doctrines of all air arms in the post-World War Two era. The USAF’s planning immediately before the Korean War focused on its role in a possible total war between the United States and the Soviet Union. It was thus unprepared and ill-equipped for the limited war in Korea and had to improvise its operations there. Findings: The inability of the USAF to conduct an unlimited war in Korea frustrated many Americans, who could not understand the political considerations that limited the conflict, seeing only that the USAF, the world’s most powerful air arm, was prevented from using all of its resources. While the resulting controversy contributed to a change of administration in the United States, it had less of an effect on the USAF. After the Korean War ended, its leadership continued to focus on unlimited war, dismissing the conflict as an aberration from which little about the operation of aircraft in war could be learned. Conclusions: The failure to recognize the lessons of the Korean War has had serious consequences. There have been no total wars since 1945; every air war of the past sixty years has been limited. Limited warfare is defined by restrictions on air power. The USAF and other air arms were slow to adapt to the changing conditions. The Korean War was a more significant event in the history of aerial warfare than is generally appreciated.
176

Environment, competitive strategy and organizational performance : a multi-dimensional empirical examination of the world commercial aviation industry from 2000 to 2002

Chan, Wai Yee January 2004 (has links)
Portfolio includes: Research paper 1. Generic business strategy taxonomy - an evolutionary perspective from conventionalism to pragmatism -- Research paper 2. Incorporating environmental dynamics into business strategy taxonomy: an empirical investigation of the global commercial aviation industry from 2000 to 2002 -- Research paper 3. Financial performance implications of multi-dimensional business strategy taxonomy: an empirical investigation of the global commercial aviation industry from 2000 to 2002.
177

E-6A aviation maintenenace training curriculum evaluation : a case study /

Taylor, Donald Wayne, January 1998 (has links)
Thesis (Ed. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [126]-137).
178

An assessment of deterioration of colour vision, contrast sensitivity and phorias as a result of hypoxia in persons resident at altitude

MacFarlane, Campbell. January 2003 (has links)
Thesis (MSc.(Aerospace Medicine)--Faculty of Health Sciences)-University of Pretoria, 2003.
179

A survey on training and education requirements of Marine Corps aviation logistics officers in preparation for sea basing

Mishoe, Roger M. January 1900 (has links) (PDF)
Thesis (M.S. in Operations Research)--Naval Postgraduate School, 2004. / Title from title screen (viewed Mar. 3, 2006). "September 2004." Includes bibliographical references (p. 87-88). Also issued in paper format.
180

An information theoretic approach for generating an aircraft avoidance Markov decision process

Weinert, Andrew Joseph 12 March 2016 (has links)
Developing a collision avoidance system that can meet safety standards required of commercial aviation is challenging. A dynamic programming approach to collision avoidance has been developed to optimize and generate logics that are robust to the complex dynamics of the national airspace. The current approach represents the aircraft avoidance problem as Markov Decision Processes and independently optimizes a horizontal and vertical maneuver avoidance logics. This is a result of the current memory requirements for each logic, simply combining the logics will result in a significantly larger representation. The "curse of dimensionality" makes it computationally inefficient and unfeasible to optimize this larger representation. However, existing and future collision avoidance systems have mostly defined the decision process by hand. In response, a simulation-based framework was built to better understand how each potential state quantifies the aircraft avoidance problem with regards to safety and operational components. The framework leverages recent advances in signals processing and database, while enabling the highest fidelity analysis of Monte Carlo aircraft encounter simulations to date. This framework enabled the calculation of how well each state of the decision process quantifies the collision risk and the associated memory requirements. Using this analysis, a collision avoidance logic that leverages both horizontal and vertical actions was built and optimized using this simulation based approach.

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