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This dissertation proposes a Dynamic Message Signs (DMS) diversion control system based on principles of existing Advanced Traveler Information Systems and Advanced Traffic Management Systems (ATMS). The objective of the proposed system is to alleviate total corridor traffic delay by choosing optimized diversion rate and alternative road signal-timing plan. The DMS displays adaptive messages at predefined time interval for guiding certain number of drivers to alternative roads. Messages to be displayed on the DMS are chosen by an on-line optimization model that minimizes corridor traffic delay. The expected diversion rate is assumed following a distribution. An optimization model that considers three traffic delay components: mainline travel delay, alternative road signal control delay, and the travel time difference between the mainline and alternative roads is constructed. Signal timing parameters of alternative road intersections and DMS message level are the decision variables; speeds, flow rates, and other corridor traffic data from detectors serve as inputs of the model. Traffic simulation software, CORSIM, served as a developmental environment and test bed for evaluating the proposed system. MATLAB optimization toolboxes have been applied to solve the proposed model. A CORSIM Run-Time-Extension (RTE) has been developed to exchange data between CORSIM and the adopted MATLAB optimization algorithms (Genetic Algorithm, Pattern Search in direct search toolbox, and Sequential Quadratic Programming). Among the three candidate algorithms, the Sequential Quadratic Programming showed the fastest execution speed and yielded the smallest total delays for numerical examples. TRANSYT-7F, the most credible traffic signal optimization software has been used as a benchmark to verify the proposed model. The total corridor delays obtained from CORSIM with the SQP solutions show average reductions of 8.97%, 14.09%, and 13.09% for heavy, moderate and light traffic congestion levels respectively when compared with TRANSYT-7F optimization results. The maximum model execution time at each MATLAB call is fewer than two minutes, which implies that the system is capable of real world implementation with a DMS message and signal update interval of two minutes.

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This work constitutes a basic study of aircraft access to the terminal area queue. It has grown out of the increasing concern in developing methods to increase airport runway. acceptance rate to alleviate the problem of airspace bottleneck. Considering mainly airline traffic in principal passenger transport, a method is presented to specify the relationship between the total waiting time, on one hand, and the number of gate positions and aircraft parking spaces on the other. This relationship enables one to derive a feasible configuration of terminal gate facilities under various saturation levels. An attempt is then made to characterize an environment under which a proposed flow strategy will be implementable. / M.S.

The book series Die Entwicklung der Flugsicherung in Deutschland has been published in German. This is the first of two translated books. This documentation on the development of air traffic control in West Germany after 1945 explains the continuation of the further development of the establishment of military tactical air traffic control units, which began under the military governments of the victorious powers and the subsequent Allied occupation forces in Germany. This transport service of the first decade after the end of the war forms the cradle of modern European air traffic control as the main component of the entire air traffic control system. It ended with the partial restoration of air sovereignty in West Germany (BRD) in 1955 and the end of supervision of the restored Federal Air Traffic Control Administration by HICOM's Allied Civil Aviation Board - CAB in mid-1956.

The operational work of air traffic controllers (ATCOs) is characterized by continuous and demanding cognitive tasks. Duties include ensuring a safe and efficient movement of aircraft, often operating in a 24/7 system necessitating shift-based work schedules. However, the nature of shift work introduces significant challenges related to fatigue and its potential impact on performance and safety. Fatigue is a complex physiological and psychological phenomenon originating from multiple factors such as prolonged wakefulness, inadequate sleep, and disruption to circadian rhythms. Those aspects are mainly influenced by working times, shift work, and the shift system itself. Fatigue can impair cognitive functions, including attention, reaction time, decision-making, and memory recall – critical abilities for ATCOs. Organizations and regulators are mandated to develop approaches aimed at reducing fatigue and the associated risks. Currently, fatigue is often managed through a compliance-based approach, which prescribes strict duty time limitations. However, this method oversimplifies fatigue as a non-issue in the workplace, merely because these limitations are adhered to. Recognizing the inaccuracy of this approach, a risk-based approach has been introduced. The approach acknowledges that varying degrees of fatigue risks may be present throughout a shift. This psychologically more accurate perspective has driven a change towards the fatigue risk management system (FRMS). A given shift system has a major influence on fatigue and is critical for any FRMS introduction. The actual shift design and scheduled roster can vary between industries and among air traffic control (ATC) organizations. Heterogenous shift systems differ in terms of fixed or irregular rotation, rotation direction, shift length, recovery times, minimum time between consecutive shifts, and maximum of worked hours per week or month. The impact of these factors on fatigue is, however, underexplored in ATC. A critical consideration of the shift system is indicated. For this dissertation, an irregular and preference-based shift system was investigated. Irregular shift systems, as opposed to fixed shift schedules, offer more variability in the distribution of work shifts over a roster period. The shift combinations do not follow a fixed order. Preference-based shift systems allow workers to request individualized rosters, encompassing their preferred shift types and duty days for the roster period. Particularly with regard to an irregular and preference-based shift system in ATC, there is a lack of systematically obtained fatigue data. The aim of this dissertation is to enhance the understanding of fatigue in an irregular and preference-based shift system in ATC. The shift system was investigated with a focus on fatigue dynamics and their relation to shift types, rostering factors, and night shift design as well as the consistency of subjective and objective fatigue data. In order to understand fatigue in the given irregular shift system, two field studies were conducted at different points in time, using a widely identical methodological approach. Both studies were conducted at an area control center. Fatigue was measured with a subjective and an objective method over a three-week period in all operational shifts at three key timepoints: beginning, middle, and end of the shift. Study 1 covered all four shift types (including morning, evening, and two night shifts) and investigated the differences within and between shift types. Moreover, the influence of the rotation direction and time between shifts was investigated. The results revealed a positive association between time on shift and objective fatigue. Objective fatigue increased significantly in the first half of all shifts, but then maintained at a certain level. However, this effect was moderated by the time of day, with night shifts resulting in overall increased objective fatigue in the middle and end of shifts compared to day shifts. Subjective fatigue increased over time only for the evening and one night shift type. Comparisons between shift types mostly showed higher subjective fatigue during night shifts compared to day shifts. Time on shift appeared to be the most relevant fatigue factor for day shifts, while the time of day was more relevant for night shifts. Individuals working the night shift had a longer continuous duty time, which likely explains the association with fatigue, even though task demands tend to be lower at night. Considering the rostering factors, shift combinations that had less than 11 hours between shifts (quick returns) and a counterclockwise rotation direction were associated with increased fatigue at the beginning of the subsequent duty. Interestingly, this effect diminished as the shifts proceeded. Analyses of the sleep quantity prior the shifts showed differences between all shift types, with the shortest sleep duration before morning shifts and longest prior to evening shifts. Discrepancies between subjective and objective fatigue were found. Study 2 focused on night shifts. A single split night shift arrangement was given. The arrangement included two mirrored night shift types (NA and NB), with sleep and operational phases alternating mid-shift. Both shifts commenced at 10 p.m., with NA starting operational work while NB begun with a sleep phase and being on-call. Around 3 a.m., NB took over from NA and continued operational work until the end of the shift at 7 a.m., while NA had the opportunity to sleep from 3 a.m. onwards and remaining on-call. In addition to the measurements at the key timepoints, subjective fatigue data was collected at four times during the operational work phase. The investigation of the split night shift arrangement showed that, regardless of the night shift type (NA or NB), there was a main effect of time on shift for both subjective and objective fatigue. Comparisons between both night shift types revealed minimal differences. Subjective higher fatigue was observed at the beginning of the shift for NB, although this effect was not observed for objective fatigue. Analysis of sleep duration prior to operational work revealed different preparation mechanisms among participants depending on the type of night shift worked. Specifically, the analysis showed that the average sleep duration prior to the shift was more than one hour shorter for NB compared to NA. However, the cumulative sleep duration prior to the operational work phase was longer for NB, as they achieved an average of three hours and 46 minutes of on-shift sleep. Again, discrepancies between subjective and objective fatigue were found. The objective of enhancing the understanding of fatigue in an irregular and preference-based shift system in ATC has been achieved. A positive association between time on shift and fatigue was found across both studies, predominantly in the first shift half. The results emphasize the crucial role of rostering in subjective and objective fatigue. The revealed discrepancies between self-evaluated (subjective) and performance-based (objective) fatigue might lead to safety risks, as individuals are not aware of reduced performance capabilities due to fatigue and they may request inadequate shift combinations. The interaction of fatigue with secondary factors is discussed, highlighting considerations when implementing an FRMS.

The documentation by Frank W. Fischer deals with the development of the German air traffic control centre for the upper airspace of southern Germany RHEIN UAC with the radio call sign RHEIN CONTROL, which was operated on the Erbeskopf in the Hunsrück from 1957 to 1968 and from 1968 to 1977 at Frankfurt am Main Airport. The Rhine UAC air traffic control centre was known to all airlines and military units flying over Germany's upper airspace in the post-war period. In addition, this air traffic control centre had already been confronted with traffic problems since the 1950s, which other air traffic control centres and air traffic control service providers in Europe only had to contend with many years later. Rhein UAC was the cradle of a variety of methods and operational procedures for air traffic control that were unknown to other air traffic services at the time, and it was the time of the Cold War. Germany was divided and the air forces of the occupying powers overcrowded the airspace with almost 2,000 combat aircraft during the day and at night. Military air operations that the population had never heard about. The Cold War - the confrontation between East and West - also took place far above the clouds in the upper airspace. But many aspects of civil and military air traffic control had not yet been regulated. Some things had not even been invented yet. In particular, the mixture of civil and military operating and control procedures was unique. The uniqueness consisted of the combination of joint operations, personnel and air traffic control procedures. Three personnel contingents, namely the US Air Force, the Federal Air Traffic Control Centre and the German Armed Forces, managed flights of all traffic categories. This also included all military training and special flights as well as the target flights of major NATO air manoeuvres.