Short Term Conflict Alert (STCA) is an automated warning system designed to alert air traffic controllers to possible loss of separation between aircraft. STCA systems are complex, with many parameters that must be adjusted to achieve best performance. Current procedure is to manually ‘tune’ the governing parameters in order to finely balance the trade-off between wanted alerts and nuisance alerts. We present an incremental approach to automatically optimising STCA systems, using a simple evolutionary algorithm. By dividing the parameter space into regional subsets, we investigate methods of reducing the number of evaluations required to generate the Pareto optimal Receiver Operating Characteristic (ROC) curve. Multi-archive techniques are devised and are shown to cut the necessary number of iterations by half. A method of estimating the fitness of recombined regional parameter subsets without actual evaluation on the STCA system is presented, however, convergence is shown to be severely stunted when relatively weak sources of noise are present. We describe a method of aggressively perturbing parameters outside of their known ‘safe’ ranges when complex inhibitory interactions are present that prevent an exhaustive search of permitted values. The scheme prevents the optimiser from repeating ‘mistakes’ and unnecessarily wasting evaluations. Results show that a more complete picture of the Pareto-optimal ROC curve may be obtained without increasing the number of necessary iterations. Efficacy of the new methods is discussed, with suggestions for improving efficiency. Sources of parameter interdependence and noise are explored and where possible mitigating techniques and procedures suggested. Classifier performance on training and test data is investigated and potential solutions for reducing overfitting are evaluated on a toy problem. We comment on potential uses of the ROC in characterising STCA performance, for comparison to other systems and airspaces. Many industrial systems are structured in a similar way to STCA, we hope that techniques presented will be applicable to other highly parametrised, expensive problem domains.

Οι πύργοι ελέγχου αεροδρομίων αποτελούν βασικό συστατικό για την ομαλή και συνεχή εξυπηρέτηση των πτήσεων πολιτικών και στρατιωτικών αεροσκαφών. Βρίσκονται εγκατεστημένοι σε κάθε αεροδρόμιο και αποτελούν το υψηλότερο κτίριο στο περιβάλλοντα χώρο, πράγμα που δικαιολογεί και τον μεγάλο αριθμό κεραυνικών πληγμάτων που μπορούν να δεχτούν. Σκοπός αυτής της διπλωματικής εργασίας είναι η μελέτη ενός συστήματος αντικεραυνικής προστασίας που βρίσκεται εγκατεστημένο σε έναν πύργο ελέγχου αεροδρομίου. Η απόδοση του συστήματος αντικεραυνικής προστασίας διαδραματίζει σημαντικό ρόλο στην αποτελεσματική λειτουργία του πύργου ελέγχου και στη γενικότερη αποτελεσματική λειτουργία του αερολιμένα. Με τη χρήση του προγράμματος εξομοίωσης αναλογικών και ψηφιακών κυκλωμάτων Orcad-Pspice, προσομοιώνεται το σύστημα αντικεραυνικής προστασίας, με βάση τον πύργο ελέγχου που του διεθνούς αερολιμένα Ελ. Βενιζέλος, μετράται το δυναμικό στη βάση του πύργου ελέγχου και τα ρεύματα στους αγωγούς καθόδου, όταν κεραυνός πλήττει το σύστημα συλλεκτήριων αγωγών. / The airport traffic control towers are a key component for the smooth and continuous service flights for both political and military aircraft. They are located at each airport and are the highest building in the surroundings, which justifies the number of lightning strikes that accepts. The purpose of this thesis is the study of a lightning protection system which is installed in an airport control tower. The efficiency of the lightning protection system constitute an important role in the effective operation of the control tower and the overall efficient operation of the airport. Using the analog and digital circuits simulation program Orcad-Pspice, the lightning protection system simulated , based on the control tower to the International airport Eleftherios Venizelos , the measured potential at the base of the control tower and the currents in the downconductors , when lightning strikes the collectors system

In the present task it is analysed the influence of centralist microprocessor traffic control system for Kaišiadorys – Radviliškis track capasity and traffic safety. It is given a lot of attention to description of the system, infrastructure reconstruction and calculations of the track Kaišiadorys – Radviliškis capasity. In the task it is given the evaluation of Kaišiadorys – Radviliškis track capasity and traffic safety. It is explored the track eploitation problems and perspectives. JSC Lietuvos geležinkeliai could use the calculation results of track capasity and intervals making trains traffic timetables, the calculations and suggestions also could be used making the exploitation plans for I and IX corridors development.

Ypatingų aplinkybių (nenumatytų atvejų) planai reikalingi tam, kad oro eismo paslaugos niekada nenutrūktų, oro eismas išliktų saugus ir jo valdymas būtų kuo efektyvesnis (pvz., būtų kuo didesnis oro erdvės pralaidumas). Atsitikus bet kokiai nenumatytai situacijai, pagal jos scenarijų sukuriamas veiksmų planas, kuriuo privaloma vadovautis ypatingomis aplinkybėmis. Pagrindinis tikslas kuriant NAP tai skrydžių saugos užtikrinimas. Tai yra didžiausias prioritetas šiandieninėje aviacijoje. Oro navigacijos paslaugų teikėjo ypatingų aplinkybių (nenumatytų atvejų) planai palyginus su Eurokontrolės ir ICAO rekomendacijomis neatitinka visų reikalavimų. Kai kuriose situacijose panaudoti veiksmų planai nepilnai atitinka realybę arba tiesiog yra nepakankamai aiškūs, todėl juos būtina tobulinti. Darbą sudaro keturios dalys, įvadas, analitinė – metodinė dalis, tiriamoji dalis bei išvados ir siūlymai, literatūros sąrašas. / Contingency planning is necessary so that air navigation service would never be interrupted and safe air traffic services would be provided at any time Whenever a non-standard situation occurs the contingency plan is prepared. The main purpose of contingency planning is both to prevent the services from inefficiency and to decrease the impact of a disaster by increasing safety. Safety in aviation is priority number one, so it is necessary to be ready for any possible situation which could interrupt ANSP’s work. When analyzed and compared with ICAO and EUROCONTROL recommendations ANSP‘s contingency plans do not fully meet the requirements and some changes should be implemented as quickly as possible. It is necessary to have an adequate operational plan for any unexpected situation. Structure: introduction, three parts of work: theoretical and analysis, investigation, conclusions and suggestions, a list of references.

Den här rapporten är en utredning och analys av lämpliga arbetsuppgifter och deras nödvändiga verktyg och hjälpmedel för en skiftledare, Watch Supervisor, vid ett framtida center för fjärrstyrda flygledningstorn, Remote Tower. Ett center för fjärrstyrda flygledningstorn är en centraliserad enhet med uppgiften att flygleda och kontrollera flygsäkerheten på och nära en eller flera flygplatser. Utgångspunkten för datainsamlingen har varit intervjuer med verksamma flygledare och skiftledare på LFV, Sveriges statliga verk för flygtrafiktjänst. Studiebesök har även gjorts vid olika enheter, både flygledartorn och radarkontrollcentraler, däribland Sundsvall RTC som är världens första central för fjärrstyrd flygledning godkänd att sättas i drift. Insamlad data har kompilerats och analyserats och en rekommendation presenteras i slutet av denna rapport angående arbetsuppgifter och verktyg för ovan nämnda skiftledare i ett RTC. Resultatet visar att rollen kommer ha stora likheter med befintliga skiftledarpositioner i den svenska flygledningen.

We elaborate upon the Herty-Illner macroscopic traffic models which include special non-local forces. The first chapter presents these in relation to the traffic models of Aw-Rascle and Zhang, arguing that non-local forces are necessary for a realistic description of traffic. The second chapter considers travelling wave solutions for the Herty-Illner macroscopic models. The travelling wave ansatz for the braking scenario reveals a curiously implicit nonlinear functional differential equation, the jam equation, whose unknown is, at least to conventional tools, inextricably self-argumentative! Observing that analytic solution methods fail for the jam equation yet succeed for equations with similar coefficients raises a challenging problem of pure and applied mathematical interest. An unjam equation analogous to the jam equation explored by Illner and McGregor is derived. The third chapter outlines refinements for the Herty-Illner models. Numerics allow exploration of the refined model dynamics in a variety of realistic traffic situations, leading to a discussion of the broadened applicability conferred by the refinements: ultimately the prediction of stop-and-go waves. The conclusion asserts that all of the above contribute knowledge pertinent to traffic control for reduced congestion and ameliorated vehicular flow. / Graduate

Ramp metering, one of the most effective solutions for improving motorway traffic flows, is playing increasingly important role in traffic management systems. Because of its capability to handle nonlinear and non-stationary problems, fuzzy logic based ramp metering algorithms have been always considered as an extremely suitable control measures to handle a complex nonlinear traffic system. This thesis proposes a genetic fuzzy approach to design a traffic-responsive ramp control algorithm for an isolated onramp. For a local ramp meter algorithm, the problem could be described as the inflow optimization of on-ramp, based on the evaluation of motorway traffic condition. If the inflow of on-ramp is considered as the decision variable, the ramp control problem could be treated as a nonlinear optimization problem of maximizing the evaluation function. The adaptive genetic fuzzy approach is actually a control approach to maximize the inflow of on-ramp under the restriction of evaluation function. In this thesis, a well-known fuzzy logic based ramp metering algorithms developed by Bogenberger is introduced and implemented with an on-ramp congestion model of Constellation Drive Interchange in a stochastic microscopic traffic simulator, Aimsun. To improve the performance of fuzzy control system, genetic algorithm is applied to tune the parameterized membership function of each fuzzy input to maintain the flow density of motorway blow the estimated congestion density. The performances of the genetic fuzzy logic control ramp metering are compared with FLC (fuzzy logic control) ramp metering by means of the percentage change of TTT (Total Travel Time) based on no control condition in Aimsun. The simulation results show the genetic fuzzy ramp metering has a more significant improvement on TTT and more strong stability to maintain system flow density than FLC ramp metering.

The quality of Machine Translation (MT) can often be poor due to it appearing incoherent and lacking in fluency. These problems consist of word ordering, awkward use of words and grammar, and translating text too literally. However we should not consider translations such as these failures until we have done our best to enhance their quality, or more simply, their fluency. In the same way various processes can be applied to touch up a photograph, various processes can also be applied to touch up a translation. This research outlines the improvement of MT quality through the application of Fluency Enhancement (FE), which is a process we have created that reforms and evaluates text to enhance its fluency. We have tested our FE process on our own MT system which operates on what we call the SAM fundamentals, which are as follows: Simplicity - to be simple in design in order to be portable across different languages pairs, Adaptability - to compensate for the evolution of language, and Multiplicity - to determine a final set of translations from as many candidate translations as possible. Based on our research, the SAM fundamentals are the key to developing a successful MT system, and are what have piloted the success of our FE process.

Thesis (MComm (Industrial Psychology))--University of Stellenbosch, 2009. / The aim of this study was to determine whether there is a relationship between Emotional Intelligence, Stress and Coping Strategies in the occupation of air traffic control. The focus was to determine whether the Emotional Intelligence of an Air Traffic Controller might have an effect on the recognition and management of stressful situations, and influence the way they select coping strategies. Due to a lack of research on air traffic control in South Africa, focus are not only on the stress levels of Air Traffic Controllers, but also how their Emotional Intelligence could assist in the recognition and management of the stress they experience, and ultimately then contribute to select appropriate Coping Strategies. A literature study discussed the role of Air Traffic Controllers, and factors that contribute to them experiencing stress. The constructs of Stress, Emotional Intelligence and Coping were elaborated on in detail. The constructs were defined as follows: Stress, as any demand eliciting a negative emotional state, that exceeds an individual’s resources to cope; Emotional Intelligence, as the process of emotional information processing consisting of the dimensions of Self Awareness, Self Regulation, Motivation, Empathy and Social Skills (Rahim & Minors, 2003); and Coping as the efforts to manage environmental and internal demands and conflicts which tax or exceed a person’s resources (Lazarus & Launier, 1978).

Business Intelligence, BI, is a tool for collecting, analysing and transforming data into useful information, information which is supposed to help making decisions and controlling a business’s operations. Business Intelligence leads to increased efficiency and optimizing the decision making within the organisation or its functions. It is designed to support the operator so that decisions are made quickly and accurately. The purpose of this study is to deliver a specification of requirements of value-adding information in a decision support system used by traffic coordinators at SJ. In order to reach the purpose, the qualitative study was designed in three steps, identification, prioritization and information analysis. The project was defined only to take one specific process in consideration: error-searching caused by vehicle damage. The study was initiated with interviews, observations and workshops and ended with an analysis of XOD, the current base of information. The study resulted in a specification of requirements, containing 21 different types of important information. Out of the 21 types of information currently existing in XOD, only about 52 % was considered value adding for the specific process. Besides that, the traffic coordinators experienced missing information, which was added in the specification of requirements. The heavy amounts of information was shown to be too much to take in consideration at once, which led to the conclusion that the business intelligence needs to be automated in order to optimize the decision making process. / Ett beslutsstöd är ett verktyg som samlar in, analyserar och omvandlar data till värdefull och agerbar information. Informationen utgör i sin tur en grund för beslutsfattning och styrning av en verksamhet. Ett beslutsstöd leder till effektivisering och optimering av beslutsfattandet inom organisationen och dess funktioner. Det finns i största mån till för att stötta medarbetaren i beslutsprocessen så att beslut fattas snabbt och korrekt. Syftet med denna studie är att leverera en kravlista på vilken information som är värdeskapande i ett beslutsstöd anpassat för rollen Trafiksamordnare på SJs Trafikledning. För att besvara syftet delades den kvalitativa studien upp i tre delar, nämligen identifiering, prioritering och informationsanalys. Projektet avgränsades till störningar orsakade av fordonsskador och den specifika process som initieras med felsökning av Driftstöd. Studien inleddes med intervjuer, observationer samt workshops och avslutades med en analys av XOD, det beslutsunderlag som medarbetarna har tillgång till idag. Resultatet som erhölls var en kravlista med 21 informationssegment, lika många som XOD innehöll vid studiens början. Av de inledande 21 informationssegmenten klassades dock enbart 52 % som värdeskapande samtidigt som det visade sig att medarbetarna upplevde att de saknade information. Mängden information som bedömts värdeskapande i den specifika processen är för stor för användaren att hantera på ett optimalt fungerande sätt. Projektets slutsats innebar därför att beslutsstödet helt eller delvis måste automatiseras för att underlätta beslutsprocessen för användaren.