Esta pesquisa trata o Problema de Programação de Tripulantes (PPT), presente no planejamento operacional das empresas aéreas. O principal objetivo do PPT é atribuir um conjunto de tarefas aos tripulantes, considerando as regulamentações trabalhistas, as regras de segurança e as políticas das empresas, de tal maneira que o custo da tripulação seja mínimo. O PPT é normalmente dividido em dois subproblemas, resolvidos sequencialmente: Problema de Determinação das Viagens (PDV) e Problema de Atribuição de Escalas (PAE). No PDV, determina-se um conjunto de viagens que cubra todos os voos planejados. Em seguida, no PAE, as escalas, compostas pelas viagens escolhidas e outras atividades como folgas, sobreavisos, reservas, treinamentos e férias, são atribuídas aos tripulantes. Esta decomposição justifica-se pela natureza combinatória do PPT, porém não incorpora as disponibilidades e as preferências dos tripulantes em ambos os subproblemas (PDV e PAE), gerando assim custos extras relacionados aos conflitos que surgem durante a atribuição das escalas aos tripulantes no PAE. Além disso, as estimativas de custos adotadas no PDV não possuem caráter global, já que o custo real da programação só pode ser obtido após a atribuição das escalas. O estado da arte envolve a solução integrada do PPT, em que se elimina a necessidade de resolver inicialmente o PDV, provendo assim uma melhor estimativa de custo e uma programação final com melhor qualidade, por considerar os custos da tripulação, as disponibilidades e preferências dos tripulantes de forma global. O problema, no entanto, é NP-Difícil. Assim sendo, a metodologia proposta nesta pesquisa objetiva a solução do PPT de forma integrada, através de um Algoritmo Genético Híbrido (AGH) associado a um procedimento de busca em profundidade, levando em conta as particularidades da legislação brasileira. A metodologia foi testada, com sucesso, para a solução de instâncias baseadas na malha real de uma empresa aérea brasileira. / This master of science research treats the Crew Scheduling Problem (CSP), as part of the airlines operational planning. The main aim of the CSP is to assign a set of tasks to crew members, considering the labor regulations, safety rules and policies of companies, such that the crew cost is minimal. The CSP is divided into two subproblems, solved sequentially: Crew Pairing Problem (CPP) and Crew Rostering Problem (CRP). First, CPP provides a set of pairings that covers all the planned flights. Then, in the CRP, the rosters, encompassing the pairings and other activities such as rest periods, alert duties, reserve duties, training times and vacations, are assigned to the crew members. This decomposition is justified by the combinatorial nature of the CSP, but it not incorporates the crew members availabilities and preferences in both subproblems (CPP and CRP), generating extra costs related to conflicts that arise during the assignment of rosters to the crew members in the CRP. Besides, the costs estimations adopted in the CPP does not have a global character, since the real cost of the global schedule can be only obtained after the assignment of the rosters. The state of the art involves the integrated solution of CSP, where the CPP does not need to be solved, thus providing a better estimated cost and a better schedule quality, considering crew costs and also crew members availabilities and preferences globally. The problem, however, is NP-Hard. Therefore, the methodology proposed in this master of science research aims to obtain an integrated solution of the CSP, through an hybrid algorithm genetic associated with a depth-first search procedure, taking into account the Brazilian legislation. The methodology was tested, with success, to solve instances related a real network of a Brazilian airline.

In order to perform their duties, airline pilots must have no clinical diagnosis of mental illness or any substance use disorder. However, provisions have been in place since the 1970s that provide for a return to work for airline pilots with alcohol problems. To date, over 5,000 airline pilots have undergone rehabilitation for Alcohol Use Disorder (AUD) and successfully returned to work. An important gap in the literature remains with regard to what extent improvements in cognitive performance may be experienced by airline pilots who complete treatment and to what extent age influences the amount of change. This study examined the archival data of 95 male Caucasian pilots who were assessed for cognitive performance shortly after entry to 30-day inpatient treatment and approximately 5 months later during the return to work evaluation. A nonexperimental within subjects design compared pre- and post-treatment scores on the Wechsler Adult Intelligence Scale-IV (WAIS-IV) full scale and 4 index scores as well as differences for age groups (25 to 44, 45 to 54, and 55 to 64). Repeated measures ANOVA revealed that there were significant gains on all WAIS-IV measures pre-post treatment for AUD. MANOVA results indicated no differences between age groups. These findings support current Federal Aviation Administration program practices with regard to returning airline pilots to work following rehabilitation and a sufficient period of abstinence. The potential of this study to promote the agenda of social change may be substantive for raising awareness of the cognitive deficits associated with AUD and how these may impact the safety of flight operations.

Inom äldreomsorgen idag finns det utmaningar iform av hög arbetsbelastning och dåliga arbetstider, vilket innebär att rekrytering är svår i verksamheterna. Den ökade arbetsbelastningen orsakar sjukskrivning, vilket i sin tur leder till mer sjukfrånvaro på arbetsplatsen. Studien bygger på enkätundersökningar hos personalen och intervjuer med andra företag för att dela med sig av tankar och arbetssätt som kan bidra till att utveckla planeringsprocessen. Studien ger idéer och verktyg för verksamheten om vad de behöver göra och förändra för att bli bättre och använda de resurser som redan finns tillgängliga i verksamheten på ett effektivt sätt. Syftet med studien är att kartlägga och förbättra planeringsprocessen för frånvaro på grund av sjukfrånvaro för att använda av alla resurser på bästa sätt i verksamheten utifrån teorier som ligger till grund för att belysa olika områden inom problemområdet och sedan hitta lösningar och verktyg för att förbättra processen. Studien har dragit slutsatsen att en uppdelning av uppgifter i dagens process kan underlätta personalens arbete när en ny roll skapas som hanterar den dagliga planeringen. Problemområden har kartlagts och presenterats tillsammans med en lösning baserad på principerna om lean filosofi och hörnstenarna. Processerna som utvecklats i studien bygger på skapandet av en ny roll för att underlätta och lindra det dagliga arbetet hos personalen. / In the field of care for the elderly today there are challenges, such as high workload and poor working hours, which means that recruitment is difficult in the operations. The increased workload causes sick leave, which in turn leads to more sickness absence in the workplace. The study is builds on surveys of the staff and interviews with other companies in order to share thoughts and working methods that can help to develop the planning process. The study provide ideas and tools for the business about what they need to do and change to get better and to use the resources already available in the business on an effective basis. The aim of the study is to map and improve the planningprocess of absence due to sickness absence in order to use best of all resources in the business based on theories that form a basis for highlighting different areas of the problem area, and then finding solutions and tools to improve the process. The study has concluded that a division of tasks into today's process can facilitate the work of the staff when a new role is created that manages the daily planning. Problem areas have been mapped and presented together with a solution based on the principles of lean philosophy and the cornerstones. The processes developed in the study are based on the creation of a new role to facilitate and relieve the daily work of the staff.

Esta pesquisa trata o Problema de Programação de Tripulantes (PPT), presente no planejamento operacional das empresas aéreas. O principal objetivo do PPT é atribuir um conjunto de tarefas aos tripulantes, considerando as regulamentações trabalhistas, as regras de segurança e as políticas das empresas, de tal maneira que o custo da tripulação seja mínimo. O PPT é normalmente dividido em dois subproblemas, resolvidos sequencialmente: Problema de Determinação das Viagens (PDV) e Problema de Atribuição de Escalas (PAE). No PDV, determina-se um conjunto de viagens que cubra todos os voos planejados. Em seguida, no PAE, as escalas, compostas pelas viagens escolhidas e outras atividades como folgas, sobreavisos, reservas, treinamentos e férias, são atribuídas aos tripulantes. Esta decomposição justifica-se pela natureza combinatória do PPT, porém não incorpora as disponibilidades e as preferências dos tripulantes em ambos os subproblemas (PDV e PAE), gerando assim custos extras relacionados aos conflitos que surgem durante a atribuição das escalas aos tripulantes no PAE. Além disso, as estimativas de custos adotadas no PDV não possuem caráter global, já que o custo real da programação só pode ser obtido após a atribuição das escalas. O estado da arte envolve a solução integrada do PPT, em que se elimina a necessidade de resolver inicialmente o PDV, provendo assim uma melhor estimativa de custo e uma programação final com melhor qualidade, por considerar os custos da tripulação, as disponibilidades e preferências dos tripulantes de forma global. O problema, no entanto, é NP-Difícil. Assim sendo, a metodologia proposta nesta pesquisa objetiva a solução do PPT de forma integrada, através de um Algoritmo Genético Híbrido (AGH) associado a um procedimento de busca em profundidade, levando em conta as particularidades da legislação brasileira. A metodologia foi testada, com sucesso, para a solução de instâncias baseadas na malha real de uma empresa aérea brasileira. / This master of science research treats the Crew Scheduling Problem (CSP), as part of the airlines operational planning. The main aim of the CSP is to assign a set of tasks to crew members, considering the labor regulations, safety rules and policies of companies, such that the crew cost is minimal. The CSP is divided into two subproblems, solved sequentially: Crew Pairing Problem (CPP) and Crew Rostering Problem (CRP). First, CPP provides a set of pairings that covers all the planned flights. Then, in the CRP, the rosters, encompassing the pairings and other activities such as rest periods, alert duties, reserve duties, training times and vacations, are assigned to the crew members. This decomposition is justified by the combinatorial nature of the CSP, but it not incorporates the crew members availabilities and preferences in both subproblems (CPP and CRP), generating extra costs related to conflicts that arise during the assignment of rosters to the crew members in the CRP. Besides, the costs estimations adopted in the CPP does not have a global character, since the real cost of the global schedule can be only obtained after the assignment of the rosters. The state of the art involves the integrated solution of CSP, where the CPP does not need to be solved, thus providing a better estimated cost and a better schedule quality, considering crew costs and also crew members availabilities and preferences globally. The problem, however, is NP-Hard. Therefore, the methodology proposed in this master of science research aims to obtain an integrated solution of the CSP, through an hybrid algorithm genetic associated with a depth-first search procedure, taking into account the Brazilian legislation. The methodology was tested, with success, to solve instances related a real network of a Brazilian airline.

The aim of this master„s thesis is detailed study of multipilot airliner?s crew in sence of optimalization of its actions, which is known as Crew Resource Management (CRM). This paper shows what is the main purpose of CRM through the air crash investigations and human factor analysis. According to this findings, the last chapter presents problems of flight crew planning and personnel selection.

We present the results of flight simulator experiments (60 runs) with randomly selected airline pilots under realistic operational conditions and discuss them in light of current fuel regulations and potential fuel starvation. The experiments were conducted to assess flight crew performance in handling complex technical malfunctions including decision-making in fourth-generation jet aircraft. Our analysis shows that the current fuel requirements of the European Aviation Safety Agency (EASA) are not sufficient to guarantee the safety target of the Advisory Council for Aviation Research and Innovation in Europe (ACARE), which is less than one accident in 10 million flights. To comply with this safety target, we recommend increasing the Final Reserve Fuel from 30 min to 45 min for jet aircraft. The minimum dispatched fuel upon landing should be at least 1 h.

Although the cruise industry and ROPAX ships have achieved steady growth with increased capacity, innovative service provisions and constantly being prepared for events of emergencies, they were not prepared for the sudden COVID-19 pandemic, and the travel restrictions and No Sail order put a halt to their services. Organisational resilience has received a growing interest in the world since its capabilities can support organisations to anticipate, cope and adapt to internal or external changes due to a crisis or unexpected event. This exploratory scenario study seeks to examine the cruise ships organisational resilience and service attributes in the context of the COVID-19 pandemic.The empirical findings have been collected by using qualitative semi-structured interviews with four key managers and decision makers within the industry. The findings were themed to find qualitative variations and then analysed in relation to the presented literature through the adaptive change cycle. The adaptive change cycle has been used to explain the drastic and partially chaotic crisis and recovery of cruise services.

No description available.

In Deutschland nehmen die Fahrgastzahlen und die Verkehrsleistung im Schienenpersonennah- und -fernverkehr in den letzten Jahrzehnten stetig zu. So stieg beispielsweise die Zahl der beförderten Fahrgäste im Schienenpersonennahverkehr von 1,96 Milliarden im Jahr 2004 auf 2,72 Milliarden im Jahr 2018. Dies entspricht einer Zunahme von fast 39%. Allerdings wird es für die Eisenbahnverkehrsunternehmen aufgrund des Fachkräftemangels immer schwieriger, die erforderlichen Transportleistungen durch Triebfahrzeugführer und Zugbegleiter abzudecken. Dies bedeutet, dass mit weniger Ressourcen mehr Transportleistung erbracht werden muss, so dass eine ressourcenschonende und gleichzeitig kosteneffiziente Personalplanung unerlässlich ist. Ziel dieser Arbeit ist die Entwicklung eines Lösungskonzepts zur optimierten und automatisierten Planung des Bahnpersonals, insbesondere zur Sicherstellung der Zugbegleitquoten von Zugbegleitern in Regionalzügen. Da es bereits eine Vielzahl von Publikationen zu Modellierungsansätzen und Lösungsmethoden im Zusammenhang mit der Schichtplanung des Bahnpersonals gibt, wird in einem ersten Schritt die relevante Literatur identifiziert und klassifiziert. Dies ist notwendig, um geeignete mathematische Formulierungen und Lösungsansätze zu ermitteln, die auch für den Spezialfall der Schichtplanungsprobleme für Zugbegleiter mit Zugbegleitquoten angewendet oder weiter modifiziert werden können. Durch die Systematisierung der relevanten Artikel nach Modellformulierungen, Zielsetzungen, betrachteten Rahmenbedingungen und Lösungsmethoden können Forschungslücken leicht identifiziert und Möglichkeiten für weitere Forschungen aufgezeigt werden. Nach einer Analyse der gegebenen rechtlichen Anforderungen, Regelungen aus Tarifverträgen, operativen Bedingungen und der Forderungen aus Verkehrsverträgen ist ein erstes Ziel dieser Arbeit die Entwicklung eines mathematischen Modells, das das gegebene Schichtplanungsproblem für Zugbegleiter mit Zugbegleitquoten darstellt. Um zunächst die Auswirkungen der neuen Restriktionen für die Zugbegleitquoten zu analysieren, können weitere in der Praxis notwendige Anforderungen (z.B. Personalkapazität an den Einsatzstellen) weggelassen und der Planungshorizont auf einen Tag begrenzt werden. Nach der Modellierung des Problems mit weiteren Restriktionen soll in dieser Arbeit ein geeigneter Lösungsansatz entwickelt werden, der vor allem die Lösbarkeit großer realer Instanzen gewährleistet. Die generierten Schichtpläne müssen den gesetzlichen, vertraglichen und betrieblichen Anforderungen genügen und die dadurch entstehenden Kosten minimieren. Da in der Praxis ein Planungszeitraum von einem Tag weder betriebswirtschaftlich sinnvoll noch kosteneffizient ist, wird als nächstes Ziel die Ausdehnung des Planungszeitraums auf mehrere Tage angestrebt. Diese Ausdehnung sollte sich sowohl auf das Modell als auch auf den entwickelten Lösungsansatz auswirken. So können weitere mehrtägige Restriktionen integriert werden, wie z.B. die gleichmäßige Verteilung der von einem Zugbegleiter besetzten Fahrten. In der Forschung ist es wichtig, eine Vergleichbarkeit bzw. eine Bewertung der Qualität des Modells oder des Lösungsansatzes herzustellen. Aus diesem Grund sollte eine Arc-Flow-Formulierung des Schichtplanungsproblems für Zugbegleiter mit Zugbegleitquoten formuliert werden, um kleine Instanzen optimal zu lösen und untere Schranken für reale Instanzen zu setzen. Um die Lösung der Arc-Flow-Formulierung zu beschleunigen und zu verbessern, wird die Anwendung von gültigen Ungleichungen validiert. Der Zweck dieser Arbeit, der sich aus den oben genannten Zielen ableitet, lässt sich in fünf Forschungsfragen zur Schichtplanung für Zugbegleiter mit Zugbegleitquoten zusammenfassen: Q1 Wie ist der aktuelle Forschungsstand zu Schichtplanungsproblemen für das Bahnpersonal und welche Forschungslücken können identifiziert werden? F2 Wie können Schichtplanungsprobleme für Zugbegleiter mit Zugbegleitquoten modelliert werden? F3 Wie können Instanzen von Schichtplanungsprobleme für Zugbegleiter mit Zugbegleitquoten im Hinblick auf die Anforderungen der Praxis gelöst werden? F4 Wie kann das entwickelte mathematische Modell und der hybride Lösungsansatz auf einen mehrtägigen Zeitraum ausgedehnt werden? Was ist das Potenzial eines integrierten Ansatzes im Gegensatz zum sequenziellen, tageweisen Ansatz? F5 Kann eine Arc-Flow-Formulierung des Schichtplanungsproblems für Zugbegleiter mit Zugbegleitquoten verwendet werden, um die Lösungsqualität des bisherigen Ansatzes zu bewerten oder sogar zu verbessern? Können gültige Ungleichungen das Verhalten der Arc-Flow-Formulierung in Bezug auf Rechenzeiten und untere Schranken verbessern?:List of Figures IV List of Tables V List of Algorithms VII List of Abbreviations VIII List of Symbols X 1 Introduction 1 1.1 Motivation 1 1.2 Basics of railway crew scheduling 3 1.3 Purpose and research questions 5 1.4 Structure of this work 6 1.5 Research design 10 2 Large-scale optimization techniques 16 2.1 Column generation 16 2.2 Dantzig-Wolfe decomposition for linear programs 18 3 Railway crew scheduling: models, methods and applications 22 3.1 Introduction 23 3.2 Crew planning in railway operations 25 3.2.1 Crew management in strategic and tactical planning 25 3.2.2 Crew scheduling in operational planning 25 3.2.3 Real-time crew re-scheduling in disruption management 27 3.2.4 Technical terms of crew scheduling 28 3.2.5 Special characteristics of transportation modes 29 3.3 Overview of RCSP literature 32 3.3.1 Planning stage 32 3.3.2 Mode 33 3.3.3 Crew type 33 3.3.4 Model 34 3.3.5 Objective 34 3.3.6 Solution method 34 3.3.7 Country 35 3.4 Model formulations, objectives and constraints of RCSP 40 3.4.1 Model formulations 40 3.4.2 Objectives 44 3.4.3 Constraints 48 3.5 Solution methods 50 3.5.1 Integer programming methods 51 3.5.2 Heuristics 54 3.5.3 Column generation 56 3.5.4 Meta-heuristics 64 3.6 Conclusion and further research opportunities 67 3.7 Decision support tools and railway crew scheduling in practice 69 4 Schichtplanung von Zugbegleitpersonal unter Berücksichtigung von Prüfquoten 74 4.1 Einleitung 75 4.2 Planungsprozesse im Schienenpersonennahverkehr 76 4.3 Problembeschreibung 78 4.3.1 Klassifikation 79 4.3.2 Betriebliche und rechtliche Rahmenbedingungen 80 4.4 Modellierung als Set-Covering-Problem 81 4.5 Modellierung der Schichtplanung der Zugbegleiter mit Prüfquoten 83 4.6 Beispiel 84 4.7 Zusammenfassung und Ausblick 88 5 A hybrid solution approach for railway crew scheduling problems with attendance rates 89 5.1 Introduction 90 5.2 Crew scheduling problem with attendance rates 90 5.3 Hybrid solution approach 92 5.4 Computational results 94 5.5 Conclusions and further research 95 6 Solving practical railway crew scheduling problems with attendance rates 97 6.1 Introduction 98 6.2 Related work 100 6.3 The crew scheduling problem with attendance rates 102 6.3.1 Analytics-based design 102 6.3.2 Problem description and practical requirements 103 6.3.3 Problem formulation 104 6.4 Solution approaches for the MCSPAR 107 6.4.1 A multi-period column generation algorithm 107 6.4.2 Solving the pricing problem 109 6.5 Artifact evaluation 112 6.5.1 Considered transport networks and experimental design 112 6.5.2 Evaluation and comparison of algorithms 114 6.6 Conclusions and further research 116 7 Valid inequalities for the arc flow formulation of the railway crew scheduling problem with attendance rates 118 7.1 Introduction 119 7.2 Related work 121 7.3 Problem description and practical requirements 122 7.4 Arc flow formulation 124 7.5 Valid inequalities 130 7.5.1 Model specic valid inequalities 130 7.5.2 Symmetry breaking constraints 131 7.5.3 Parallel arcs 132 7.5.4 Fixed arcs 132 7.6 Computational results 133 7.6.1 Small-sized instances 134 7.6.2 Bounds for real-world instances 138 7.6.3 Improve heuristic solution 139 7.7 Conclusion 140 8 Conclusion 144 8.1 Summary 144 8.2 Future research 148 A Declarations of authorship 151 Bibliography 155 / In Germany, the number of passengers and the transport performance in regional and long-distance rail passenger transport increase constantly over the last decades. For example, the number of passengers carried in regional rail passenger transport rose from 1.96 billion in 2004 to 2.72 billion in 2018. This represents an increase of almost 39%. However, it is becoming increasingly difficult for railway companies to cover the required transport services by drivers and conductors due to the shortage of skilled workers. This implies that a greater transport performance must be achieved with fewer resources, thus resource-saving and at the same time cost-efficient planning of personnel is essential. This work aims to develop a solution concept for optimized and automated railway crew scheduling, especially ensuring attendance rates for conductors in regional trains. Since there already exists a variety of publications concerning modeling approaches and solution methods related to railway crew scheduling, the first step is to identify and classify relevant literature. This is necessary to determine suitable mathematical formulations and solution approaches which can also be used or further modified for the special case of railway crew scheduling problems with attendance rates for conductors. By systematizing the reviewed articles according to model formulations, objectives, constraints and solution methods, research gaps can easily be identified and opportunities for further research can be revealed. After an analysis of the given legal requirements, regulations from labor contracts, operating conditions and claims under transportation contracts, a first goal of this work is the development of a mathematical model which represents the given problem with attendance rates for conductors. In order to first analyze the effect of the new constraints on attendance rates, further requirements necessary in practice can be omitted (e.g. personnel capacity at crew bases) and the planning horizon can be limited to one day. After modeling the problem with further requirements, this work aims to develop a suitable solution approach which, above all, guarantees the solvability of large real-world instances. The generated shift schedules have to meet legal, contractual and operational requirements and thereby minimize the resulting costs. Since in practice a planning period of one day is neither operationally reasonable nor cost-efficient, the next goal is to extend the planning period to several days. This extension should affect both the model and the developed solution approach. This allows further restrictions concerning several days to be integrated, such as the uniform distribution of attended trips. In research, it is important to establish comparability or an assessment of the quality of the model or solution method. For this reason, an arc-flow formulation of the crew scheduling problem with attendance rates should be formulated to solve small-sized instances optimally and provide lower bounds for real-world instances. To accelerate and improve the arc-flow formulation solution, the application of valid inequalities will be validated. The purpose of this work derived from the above mentioned objectives can be summarized into five research questions on railway crew scheduling with and without attendance rates for conductors: Q1 What is the current state of research for railway crew scheduling problems and which research gaps can be identified? Q2 How can railway crew scheduling problems with attendance rates for conductors be modeled? Q3 How can instances of railway crew scheduling problems with attendance rates be solved with regard to real-world requirements? Q4 How can the developed mathematical model and hybrid solution approach be extended to a multiple day period? What is the potential of an integrated approach in contrast to the sequential day-by-day approach? Q5 Can an arc-flow formulation of the railway crew scheduling problem with attendance rates be used to evaluate or even enhance the solution quality of the previous approach? Can valid inequalities improve the performance of the arc-flow formulation concerning computing times and lower bounds?:List of Figures IV List of Tables V List of Algorithms VII List of Abbreviations VIII List of Symbols X 1 Introduction 1 1.1 Motivation 1 1.2 Basics of railway crew scheduling 3 1.3 Purpose and research questions 5 1.4 Structure of this work 6 1.5 Research design 10 2 Large-scale optimization techniques 16 2.1 Column generation 16 2.2 Dantzig-Wolfe decomposition for linear programs 18 3 Railway crew scheduling: models, methods and applications 22 3.1 Introduction 23 3.2 Crew planning in railway operations 25 3.2.1 Crew management in strategic and tactical planning 25 3.2.2 Crew scheduling in operational planning 25 3.2.3 Real-time crew re-scheduling in disruption management 27 3.2.4 Technical terms of crew scheduling 28 3.2.5 Special characteristics of transportation modes 29 3.3 Overview of RCSP literature 32 3.3.1 Planning stage 32 3.3.2 Mode 33 3.3.3 Crew type 33 3.3.4 Model 34 3.3.5 Objective 34 3.3.6 Solution method 34 3.3.7 Country 35 3.4 Model formulations, objectives and constraints of RCSP 40 3.4.1 Model formulations 40 3.4.2 Objectives 44 3.4.3 Constraints 48 3.5 Solution methods 50 3.5.1 Integer programming methods 51 3.5.2 Heuristics 54 3.5.3 Column generation 56 3.5.4 Meta-heuristics 64 3.6 Conclusion and further research opportunities 67 3.7 Decision support tools and railway crew scheduling in practice 69 4 Schichtplanung von Zugbegleitpersonal unter Berücksichtigung von Prüfquoten 74 4.1 Einleitung 75 4.2 Planungsprozesse im Schienenpersonennahverkehr 76 4.3 Problembeschreibung 78 4.3.1 Klassifikation 79 4.3.2 Betriebliche und rechtliche Rahmenbedingungen 80 4.4 Modellierung als Set-Covering-Problem 81 4.5 Modellierung der Schichtplanung der Zugbegleiter mit Prüfquoten 83 4.6 Beispiel 84 4.7 Zusammenfassung und Ausblick 88 5 A hybrid solution approach for railway crew scheduling problems with attendance rates 89 5.1 Introduction 90 5.2 Crew scheduling problem with attendance rates 90 5.3 Hybrid solution approach 92 5.4 Computational results 94 5.5 Conclusions and further research 95 6 Solving practical railway crew scheduling problems with attendance rates 97 6.1 Introduction 98 6.2 Related work 100 6.3 The crew scheduling problem with attendance rates 102 6.3.1 Analytics-based design 102 6.3.2 Problem description and practical requirements 103 6.3.3 Problem formulation 104 6.4 Solution approaches for the MCSPAR 107 6.4.1 A multi-period column generation algorithm 107 6.4.2 Solving the pricing problem 109 6.5 Artifact evaluation 112 6.5.1 Considered transport networks and experimental design 112 6.5.2 Evaluation and comparison of algorithms 114 6.6 Conclusions and further research 116 7 Valid inequalities for the arc flow formulation of the railway crew scheduling problem with attendance rates 118 7.1 Introduction 119 7.2 Related work 121 7.3 Problem description and practical requirements 122 7.4 Arc flow formulation 124 7.5 Valid inequalities 130 7.5.1 Model specic valid inequalities 130 7.5.2 Symmetry breaking constraints 131 7.5.3 Parallel arcs 132 7.5.4 Fixed arcs 132 7.6 Computational results 133 7.6.1 Small-sized instances 134 7.6.2 Bounds for real-world instances 138 7.6.3 Improve heuristic solution 139 7.7 Conclusion 140 8 Conclusion 144 8.1 Summary 144 8.2 Future research 148 A Declarations of authorship 151 Bibliography 155

Il s’agit de l’emploi de la technologie numérique dans la mise en scène de la tragédie grecque antique, en d’autres termes, de la réception de la tragédie grecque au sein du théâtre digital. En tant que performance digitale la tragédie grecque semble fonctionner comme un kaléidoscope du temps ; tout à la fois comme une lentille ou un miroir écrasé, où se développent  un jeu, un « aller-retour » entre les identités et les qualités : spectateur / citoyen, politique / religieux, espace-temps du mythe / temps actuel, présence / absence. Grâce à l’emploi de la technologie et d’équivalents digitaux, les artistes reconceptualisent une série de notions de la tragédie telles que la communauté, la cité, l’hybris, le masque, le conflit, le tragique, et ils proposent des expériences sensorielles équivalentes au spectateur contemporain : les médias numériques deviennent un équivalent de la parole. Oikos, le palais royal, lieu devant lequel et au sein duquel se déroulent la plupart des événements et conflits, est remplacé par l’écran palimpseste ; on est dans l’image dans laquelle on vit désormais, c’est au sein de l’écran que l’on produit l’Histoire. La convention du masque conduit à l’expérimentation avec des technologies sonores. La fonction politique de la tragédie grecque et la création de l’effet de communauté, se produisent désormais par le biais de la technologie numérique. Les spectateurs forment des communautés éphémères lors de leurs réunions dans l’environnement technologique, la fragmentation rhizomatique de la scène « cache » la communauté, pour la transformer en une communauté virtuelle. Enfin, c’est le tragique qui se développe sur scène en tant qu’idée et phénomène performatif. / The thesis focuses on the use of digital technology in the staging of Greek Tragedy that is, the reception of Greek tragedy in the digital theatre. Greek tragedy, when digitally staged, seems to function as a kaleidoscope of our times; sometimes a lens and at others a shattered mirror, where a game, a "toing and froing" between identities and qualities exists: spectator/citizen, political/religious, time-space of myth/actual current time, presence/absence. With the use of technology and of digital equivalents, artists re-conceptualize a series of key notions such as the community, the city, the hubris, the mask, the conflict, the tragic and create equivalent effects for the contemporary spectator: Digital media becomes the equivalent of discourse. The “oikos”, the royal palace, in front of and within which most events and conflicts occur, is replaced by the screen-palimpsest: it is within the image that we live, we clash, we make history. The mask convention leads to experimentation with sound technologies. The much-discussed political function of tragedy in the context of democratic Athens and the building of a sense of community is now realised through digital technology. Spectators form ephemeral communities in their meeting within the technological environment, the rhizomatic fragmentation of the theatre stage, "hides" the community to transform it into a virtual community. In the end, it is the tragic that is being developed as an idea and a performative phenomenon. / Στο επίκεντρο βρίσκεται η χρήση της ψηφιακής τεχνολογίας στη σκηνοθεσία της αρχαίας ελληνικής τραγωδίας, δηλαδή η πρόσληψη της αρχαίας ελληνικής τραγωδίας στο ψηφιακό θέατρο. H αρχαία ελληνική τραγωδία ως ψηφιακή παράσταση, μοιάζει να λειτουργεί ως καλειδοσκόπιο του καιρού∙ άλλοτε ως φακός και κάποιες φορές ως θρυμματισμένος καθρέπτης, όπου ένα παιχνίδι, ένα «πήγαινε-έλα» αναπτύσσεται ανάμεσα στις ταυτότητες και τις ποιότητες : θεατής/πολίτης, πολιτικό/θρησκευτικό, ο χωροχρόνος του μύθου/ο πραγματικός τρέχων χρόνος, παρουσία/απουσία. Με τη χρήση της τεχνολογίας και των ψηφιακών ισοδυνάμων, οι καλλιτέχνες επανοηματοδοτούν στο παρόν μια σειρά κομβικών εννοιών για την τραγωδία, όπως η κοινότητα, η πόλις, η ύβρις, η μάσκα, η σύγκρουση, το τραγικό και δημιουργούν ισοδύναμες αισθήσεις και εντυπώσεις στον σύγχρονο θεατή: Τα ψηφιακά μέσα γίνονται ισοδύναμο του λόγου. Ο οίκος, το βασιλικό ανάκτορο μπροστά και εντός του οποίου συντελούνται τα περισσότερα γεγονότα και οι συγκρούσεις, αντικαθίσταται από την οθόνη παλίμψηστο: μέσα στην εικόνα ζούμε, συγκρουόμαστε, παράγουμε ιστορία. Η σύμβαση της μάσκας οδηγεί στον πειραματισμό με τις τεχνολογίες του ήχου. Η πολυσυζητημένη πολιτική λειτουργία της τραγωδίας στο πλαίσιο της δημοκρατικής Αθήνας και η δημιουργία του αισθήματος κοινότητας δημιουργείται πλέον μέσα από την ψηφιακή τεχνολογία. Oι θεατές σχηματίζουν εφήμερες κοινότητες στη συνάντησή τους μέσα στο τεχνολογικό περιβάλλον, η ριζωματική θραυσματοποίηση της θεατρικής σκηνής, «κρύβει» την κοινότητα, για να τη μετατρέψει σε εικονική κοινότητα. Τέλος, είναι το τραγικό που αναπτύσσεται ως ιδέα και ως επιτελεστικό φαινόμενο.