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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.
31

Applying Data Analytics to Freight Train Delays in Shunting Yards

Minbashi, Niloofar January 2020 (has links)
The European Commission has foreseen a modal share of 30% by 2030 for rail freight transport. To achieve this increase in the modal share, enhanced reliability of rail freight services is required. Optimal functioning of shunting yards is one of the areas that can improve this reliability. Shunting yards are large areas allocated to reassemble freight trains for dispatching to new destinations. Their productivity has a direct impact on the overall performance of a rail freight network. Therefore, analysing and modelling of departure deviations from shunting yards are required to enhance the interactions between shunting yards and the network; this thesis contributes to this gap. Paper I investigates the probability and temporal distribution of departure deviations using a large data set comprising 250,000 departures over seven years from two main shunting yards (Malmö and Hallsberg) in Sweden. The probability distribution of departure deviations is found comparing four main distributions including the exponential, the log-normal, the gamma, and the Weibull according to the maximum likelihood estimates and the results of the Anderson-Darling goodness of fit test.  The log-normal and the gamma are shown the best fits for departure deviations: the former on delays, and the latter on early departures. In the temporal delay distribution, the weekly and monthly, but not yearly delayed departures are positively correlated with the network usage. However, for hourly delayed departures, a shunting yard involved with international traffic does not show any correlation between delayed departures and the network usage, whereas a domestic shunting yard shows a significant negative correlation between these two parameters.  The findings obtained from this thesis contribute to a better understanding of departure deviations from shunting yards, and can be applied in enhancing the operations and capacity utilization of shunting yards in future models. Papers II and III analyse the relationship between congestion in the arrival yard and departure delays using the same data set as paper I.  According to previous research, congestion plays an important role in shunting yard delays. With defining congestion as the number of arriving trains before departure time, paper II analyses this relationship limiting the arrivals and departures between the two shunting yards considering varying time periods before departure,whereas Paper III elaborates the analysis by defining congestion level in a fixed period of time before departure time including all arrivals and departures. Considering the data set used in the analysis, the results show that there is no significant relationship between the congestion in the arrival yard and departure delays of trains. It is possible that congestion may not impact the departure delays of trains, but it may impact the departure delays of wagons due to missed wagon connection or increasing wagon idle time, which can be explored with the availability of wagon connection data.  Additionally, future elaboration of congestion definition, covering congestion at the shunting yard level, may lead to further improved analyses. / Europeiska kommissionen har förutspått en markansandel på 30% framtill 2030 för järnvägstransporter av gods. För att uppnå denna ökning krävsökad tillförlitlighet hos järnvägstransporttjänster. Rangergodsbangårdars optimalafunktion är ett av de områden som kan förbättra denna tillförlitlighet.Rangergodsbangårdar stora områden som är avsedda för att koppla ihopgodståg för sändning till nya destinationer. Deras produktivitet har en direktinverkan på järnvägsnätets totala prestanda. Därför krävs analys och modelleringav avvikelser från dessa noder för att förbättra interaktionen mellanrangergodsbangårdar och järnvägsnätet. I papper I undersöks sannolikheten och den tidsmässiga fördelningen avavvikelser med hjälp av en stor datamängd som omfattar 250 000 avgångaröver sju år från två rangergodsbangårdar (Malmö och Hallsberg) i Sverige.Sannolikhetsdistributioner av avvikelser jämförs med fyra huvuddistributioner,exponentiell, log-normal, gamma och Weibull enligt de maximalasannolikhetsuppskattningarna och resultaten av Anderson-Darling godhetav passningstest. Log-normal och gamma visar sig passa bäst för avvikelser:den förstnämnda vid förseningar och den senare vid tidiga avgångar. I dentidsmässiga fördröjningsfördelningen är de veckovisa och månatliga men inteårliga försenade avgångarna positivt korrelerade med järnvägsnätets nyttjandegrad.För försenade avgångar per timme visar dock en rangergodsbangårdsom är inblandad i internationell trafik ingen korrelation mellan försenadeavgångar och järnvägsnätets nyttjandegrad, medan en inhemsk rangergodsbangårdvisaren signifikant negativ korrelation mellan dessa två parametrar.Resultaten från denna avhandling bidrar till en bättre förståelse av avvikelserfrån rangergodsbangårdar och kan användas för att förbättra drift och kapacitetsutnyttjandeav rangergodsbangårdar växelplatser i framtida modeller. Papper II och III analyserar förhållandet mellan trängsel i ankomstgårdenoch avgångsförseningar med hjälp av samma datamängd som i papperI. Enligt tidigare analyser spelar trängsel en viktig roll vid förseningar förrangergodsbangårdar. Trängsel definieras som antalet ankommande tåg föreavgångstid och papper II analyserar detta förhållande som begränsar ankomsteroch avgångar mellan de två rangergodsbangårdar med beaktande av olikatidsperioder före avgång, medan papper III utvecklar analysen genom attdefiniera trängselnivån under en fast tidsperiod före avgångstid inklusive allaankomster och avgångar. Med tanke på datamängden som användes i analysenvisar resultaten att det inte finns något signifikant samband mellan trängselni ankomstgården och tågens förseningar. Det är möjligt att trängsel kanskeinte påverkar tågens avgångsfördröjningar, men det kan påverka vagnarnasavgångsfördröjningar på grund av missad vagnanslutning eller öka vagnenstomgångstid, vilket kan undersökas med vid tillgång av vagnanslutningsdata.Dessutom kan framtida vidareutveckling av definitionen av trängsel som påen detaljerad nivå täcker rangergodsbangårdars alla delar, leda till ytterligareförbättrade analyser. / <p>QC 20201105</p> / Shift2Rail / FR8HUB
32

1D LIDAR Speed and Motion for the Internet-of-Things : For Railroad Classification Yards / 1D LIDAR hastighet och rörelse för sakernas internet : För rangerbangårdar

Chancellor, Edward, Oikarinen, Kasper January 2021 (has links)
This thesis is an investigation into the feasibility of one-dimensional Light Detection and Ranging (LIDAR) sensors for tracking the position and motion of trains on railroad classification yards. Carefully monitoring railway traffic in these areas is important, in order to avoid accidents, optimise logistical operations and hence reduce delays. However, existing technologies for tracking trains on regular stretches of train-line, including Radio Frequency Identification (RFID) and Global Positioning System (GPS), have various drawbacks when applied to classification yards. As such, it is pertinent to investigate the extent to which simple LIDAR sensors could be used for this purpose, as part of a basic Internet of Things (IoT) system. To tackle this problem, we considered different ways of positioning the sensors around railway tracks. We then proposed a floating average algorithm for calculating a target object’s velocity using continuous LIDAR distance readings. To know when to apply the algorithm as a train is passing the sensor, we observed how the distance readings varied as a model train passed the sensor. The data was used to construct a Finite-state machine (FSM) that can fully describe the status of trains as they pass the sensor. In order to test our solution, we constructed a prototype sensor node implementing the FSM and evaluated its performance first with a model train and then on actual commuter trains on an outdoors train platform. We found that one-dimensional LIDAR sensors could feasibly be deployed to monitor the position and motion of trains with a high degree of consistency and accuracy. However, LIDAR may need to be corroborated with other types of technology such as RFID so that trains can be distinguished from other moving objects. / Detta projekt undersöker möjligheten att använda endimensionella Light Detection and Ranging (LIDAR) sensorer för att spåra läge och rörelse av tåg på rangerbangårdar. Att övervaka tågtrafik i dessa områden är viktigt för att undvika trafikolyckor, optimera logistiska operationer och därmed minska förseningar. Dagens teknik för att spåra tåg på vanliga tågspår, till exempel Radio Frequency Identification (RFID) och Global Positioning System (GPS), har flera begränsningar när de ska användas till rangerbangårdar. Följaktligen så är det relevant att undersöka till vilken grad enkla LIDAR sensorer kan tillämpas för detta ändamål som en del av ett Internet of Things (IoT) system. För att lösa detta problem, övervägde vi olika sätt att placera sensorerna kring tågspår. Därefter implementerade vi en glidande medelvärdealgoritm för att beräkna målobjektets hastighet genom att använda kontinuerliga LIDAR avståndsmätningar. För att kunna veta när algoritmen skulle tillämpas när riktiga tåg passerade sensorn, noterade vi först hur avståndsmätningarna varierade när ett modelltåg passerade sensorn. Mätningarna användes sedan för att konstruera en ändlig tillståndsmaskin (FSM) som kan fullständigt beskriva statusen av tåget när det åker förbi sensorn. För att testa vår lösning, tillverkade vi en sensornodprototyp med vår FSM implementerad och utvärderade först dess prestationsförmåga med ett modelltåg och sedan med riktiga pendeltåg.Vi observerade att endimensionella LIDAR sensorer kan användas för att övervaka läge och hastighet av tåg med hög precision och konsekventa resultat. Däremot visade sig att LIDAR ska med fördel kombineras med andra typer av teknologi, som till exempel RFID, för att urskilja tåg från andra objekt i rörelse.
33

Nová Jižní čtvrť a její propojení s řekou Svratkou / New South District and its Connection to Svratka

Leitmannová, Barbora January 2019 (has links)
The Master‘s thesis deals with the processing of the architectural study of the city block in the planned new South Quarter near the Svratka River. The project builds on a pre-diploma project whose aim was to create a territorial urban study for part of this neighbourhood. It was a section between the New Railway Station, Opuštěná Street and the existing Zvonařka Bus Station following the river embankment. The subject of the master‘s thesis is a block from this newly designed urban structure, situated in very close proximity to the river. he project focuses on the block as a whole. It conceptually solves the links between newly designed buildings, individual operations, and functions. It deals with the relationship between streets, river and buildings. Great attention is paid to the maximum use of greenery in the form of extensive and intensive roofs, internal blocks, private gardens in the inner block, as well as private front gardens. The concept seeks to provide a wide range of options and differences. This creates a closed city block that is open and responding to the river with its shape, that consists of free parts. The first / majority are the street lining. It is mostly 5-storey. Corner buildings are raised by one floor, allowing roof intensive gardens to be created. It includes a diverse range of residential units overlooking the river. Housing prevails here. On the ground floor there are a few commercial units and work-and-live. The work-and-live area also includes a private front yard on the street and private raised gardens in the interior. The second part consists of two objects extended over the pedestrian shopping promenade. One of the objects was subject of my detailed architectural study. There are the most luxurious apartments, ground floor showroom and concept store. The third part consists of a lowered 2-storey embankment building, which by its height provides the rest of the block with a beautiful, unimpeded view of the river. It covers the
34

[en] ASSESSMENT OF THE PROCESSING CAPACITY IN SORTING RAILWAY YARDS THROUGH OPTIMIZATION MODEL / [pt] AVALIAÇÃO DE CAPACIDADE DE PROCESSAMENTO EM PÁTIOS FERROVIÁRIOS PLANOS DE CLASSIFICAÇÃO ATRAVÉS DE MODELO DE OTIMIZAÇÃO

RENATA FERREIRA DE SA 08 November 2021 (has links)
[pt] Este trabalho trata do problema real de avaliar a capacidade de processamento de pátios ferroviários planos de classificação. Nesses pátios, os vagões são recebidos em trens e movimentam respeitando a disposição dos trilhos e a formação sequencial do trem de saída. Movimentações ineficientes implicam em uma capacidade de processamento inferior à potencial do pátio dado seu layout. O objetivo desta pesquisa é descrever o problema e incitar um método capaz de calcular a capacidade de processamento de pátios ferroviários planos de classificação no horizonte estratégico, indicando se existe ou não a necessidade de um projeto de expansão para garantir atendimento à demanda prevista. O problema foi modelado através de programação linear inteira mista (MILP) baseado na teoria de sequenciamento de produção. O modelo foi aplicado em instâncias de teste, reproduzindo movimentações reais de vagões, e provou avaliar diferentes layouts adequadamente, porém com elevado tempo de execução. A inicialização de algumas variáveis binárias do modelo permitiu um incremento de tamanho nas instâncias, porém ainda inviável para aplicação na prática. / [en] This work deals with the real problem of evaluating the processing capacity of flat rail classification yards. In these yards, the railway cars are received on trains and move respecting the car sequence of the outgoing train. Inefficient movements imply a lower processing capacity than the yard s potential given its layout. The objective of this research is to describe the problem and to incite a method capable of calculating the processing capacity of flat rail classification yards in the strategic horizon, indicating whether or not there is a need for an expansion project to ensure meeting the expected demand. The problem was modeled using mixed integer linear programming (MILP) based on production scheduling theory. The model was applied to test instances, reproducing real railway car movements, and proved to evaluate different layouts properly, but with a high execution time. The initialization of some binary variables of the model allowed an increase in the size of the instances, however it is still unfeasible for practical application.
35

LiDAR-Equipped Wireless Sensor Network for Speed Detection on Classification Yards / LiDAR-utrustat sensornätverk för hastighetsmätning på rangerbangårdar

Olsson, Isak, Lindgren, André January 2021 (has links)
Varje dag kopplas tusentals godsvagnar om på de olika rangerbangårdarna i Sverige. För att kunna automatiskt bromsa vagnarna tillräckligt mycket är det nödvändigt att veta deras hastigheter. En teknik som har blivit populär på sistone är Light Detection and Ranging (LiDAR) som använder ljus för att mäta avstånd till objekt. Den här rapporten diskuterar design- och implementationsprocessen av ett trådlöst sensornätverk bestående av en LiDARutrustad sensornod. Designprocessen gav en insikt i hur LiDAR-sensorer bör placeras för att täcka en så stor yta som möjligt. Sensornoden var programmerad att bestämma avståndet av objekt genom att använda Random Sample Consensus (RANSAC) för att ta bort outliers och sen linjär regression på de inliers som detekterats. Implementationen utvärderades genom att bygga ett litet spår med en låda som kunde glida fram och tillbaka över spåret. LiDAR- sensorn placerades med en vinkel vid sidan om spåret. Resultaten visade att implementationen både kunde detektera objekt på spåret och också hastigheten av objekten. En simulation gjordes också med hjälp av en 3D-modell av en tågvagn för att se hur väl algoritmen hanterade ojämna ytor. LiDAR-sensorn i simuleringen hade en strålavvikelse på 0_. 30% av de simulerade mätvärdena gjordes om till outliers för att replikera dåliga väderförhållanden. Resultaten visade att RANSAC effektivt kunde ta bort outliers men att de ojämna ytorna på tåget ledde till felaktiga hastighetsmätningar. En slutsats var att en sensor med en divergerande stråle möjligtvis skulle leda till bättre resultat. Framtida arbete inkluderar att utvärdera implementationen på en riktig bangård, hitta optimala parametrar för algoritmen samt evaluera algoritmer som kan filtrera data från ojämn geometri. / Every day, thousands of train wagons are coupled on the multiple classification yards in Sweden. To be able to automatically brake the wagons a sufficient amount, it is a necessity to determine the speed of the wagons. A technology that has been on the rise recently is Light Detection and Ranging (LiDAR) that emits light to determine the distance to objects. This report discusses the design and implementation of a wireless sensor network consisting of a LiDAR-equipped sensor node. The design process provided insight into how LiDAR sensors may be placed for maximum utilization. The sensor node was programmed to determine the speed of an object by first using Random Sample Consensus (RANSAC) for outlier removal and then linear regression on the inliers. The implementation was evaluated by building a small track with an object sliding over it and placing the sensor node at an angle to the side of the track. The results showed that the implementation could both detect objects on the track and also track the speed of the objects. A simulation was also made using a 3D model of a wagon to see how the algorithm performs on non-smooth surfaces. The simulated LiDAR sensor had a beam divergence of 0_. 30% of the simulated measurements were turned into outliers to replicate bad weather conditions. The results showed that RANSAC was efficient at removing the outliers but that the rough surface of the wagon resulted in some incorrect speed measurements. A conclusion was made that a sensor with some beam divergence could be beneficial. Future work includes testing the implementation in real-world scenarios, finding optimal parameters for the proposed algorithm, and to evaluate algorithms that can filter rough geometry data.
36

Shipbuilding and timber management in the Royal Dockyards 1750-1850 : an archaeological investigation of timber marks

Atkinson, Daniel Edward January 2007 (has links)
This work presents a study of shipbuilding and timber management in the Royal Dockyards in the period 1750 – 1850, focusing on an archaeological investigation of ship timber marks. The first chapter outlines the concept of timber marking in shipbuilding contexts, stressing the multi-disciplinary approach to the study highlighted in the available archaeological and documentary evidence by which the practice of timber marking can be understood. Chapter two outlines the background to timber marking in the Georgian era and the development of the practice within the broader advances made in shipbuilding, technology and design prior to the end of the 17th century. Chapter three outlines the developments in shipbuilding and the introduction of systems to control and standardise the management of timber in the Royal Dockyards in the 18th century. In the latter half of the 18th century we will see the attempts of naval reformers to develop these systems of timber management and pave the way for the sweeping changes made at the beginning of the 19th century. Chapter four highlights these changes with the introduction of the Timber Masters and looks at the nature of timber management and the marking of timbers as identified in documentary sources. This evidence lays the foundation for the understanding of timber marking in the 19th century as witnessed in the archaeological record. The remaining chapters present the much more extensive archaeological evidence for timber marking among several high profile assemblages. The main assemblages presented in Chapters 5 to 9 show the diversity of timber marking practices and how they relate to the working processes of the Royal Dockyards. The research offers new insights into the understanding of shipbuilding and the management of timber in the Royal Dockyards between 1750 and 1850 and explores the possibilities for further avenues of study.
37

Effective public relations in a transformed organisation : Naval Base Simon's Town as a case study

Theunissen, J. D. J. 03 1900 (has links)
Thesis (MPA)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Public Relations is a discipline where the basic concepts and functions remain the same, be it in a public or private organisation. It is ultimately a staff function, which is responsible for effective two-way communication between an organisation and its publics, both internal and external. With the transformation in the Department of Defence and ultimately the South African National Defence Force (SANDF), major changes took place structurally as well as in terms of the execution of functions on the operational level where Naval Base Simon’s Town (NB Smst) is one of the new General Support Bases of the SANDF. The Public Relations Section of NB Smst must deliver public relations services to the clients of NB Smst. The purpose of this study is to establish whether the services that the Public Relations Section delivers to its clients are in line with the expectations of the clients. An in-depth study is made of the theory of public relations, starting with the overall concept of communication. The transformation of the SANDF is discussed in detail and the concept of how public relations is supposed to be executed is researched. A needs assessment survey was done and the recommendations listed. The research established that although the Section is functioning in line with international and national principles and procedures the clients’ perceptions are that the Section does not deliver the quality of service they expect. / AFRIKAANSE OPSOMMING: Openbare Skakeling is ’n dissipline waar die basiese konsepte en funksies ooreenstem binne publieke sowel as private organisasies. Dit is hoofsaaklik ’n staffunksie wat verantwoordelik is vir die effektiewe twee-rigting kommunikasie tussen ’n organisasie en sy publiek, beide intern sowel as ekstern. Met die transformasie van die Departement van Verdediging en uiteindelik die Suid- Afrikaanse Nasionale Weermag (SANW), het grootskaalse veranderinge plaasgevind, struktureel sowel as ten opsigte van die uitvoering van funksies op die operasionele vlak waar Vlootbasis Simonstad (VB Smst), een van die SANW se Algemene Steunbasisse, opereer. Die Openbare Skakelseksie van VB Smst is verantwoordelik vir die lewering van openbare skakeldienste aan die kliente van VB Smst. Die doel van hierdie studie is om te bepaal of die dienste wat deur die Openbare Skakelseksie gelewer word in lyn is met die kliente se verwagtinge. ’n In-diepte studie is gedoen ten opsigte van die teorie van openbare skakeling, beginnende met die totale konsep van kommunikasie. Die transformasie van die SANW word in detail bespreek. Dit word gevolg deur die navorsing oor hoe openbare skakeling veronderstel is om uitgevoer te word, ’n Behoeftebepaling is gedoen en aanbevelings word gelys. Die navorsing se bevindings is dat alhoewel die Seksie volgens internasionale en nasionale konsepte en prosedures funksioneer, die kliente se persepsies is dat die Seksie nie die kwaliteit dienste lewer wat hulle verwag nie.
38

Energy matters: evaluating the use of the energy mapping approach in Winnipeg, Manitoba

Friesen, Andrei 22 April 2014 (has links)
In light of pressing challenges including climate change and energy security, urban planners are increasingly being required to make decisions that can be attributed to reductions in energy use and greenhouse gas emissions. Energy mapping is an emerging approach used to make improved energy-related decisions and predict energy performance, although at the time of writing, has not been applied within a Manitoban context. Informed by promising practice utilized in other Canadian locales, this research creates an energy mapping process for use in the City of Winnipeg’s residential sector. The Ebby-Wentworth neighbourhood is analyzed to develop and test the mapping process. The process begins with determining baseline energy use for the neighbourhood, and is then compared to three development scenarios, which include the use of retrofits, and new construction on an adjacent development site. The results of applying the energy mapping approach in Winnipeg demonstrates this to be a key decision-making tool for planners looking to make informed decisions related to energy-using equipment, building and site design, and land use and infrastructure. Recommendations include: increased use of the energy mapping approach as a decision-making tool through enhanced collaboration between federal and provincial authorities, municipalities, and utilities; incorporating energy considerations into the planning and development process through revised and updated energy legislation, policy and programming; and, further refining and testing of the energy mapping process designed for this research to develop a best-practice approach for mapping energy use within the Province of Manitoba.
39

Planning Resource Requirements in Rail Freight Facilities by Applying Machine Learning

Ruf, Moritz 10 January 2022 (has links)
Diese Dissertation verknüpft eisenbahnbetriebswissenschaftliche Grundlagen mit Methoden aus den Disziplinen Unternehmensforschung (Operations Research) und Maschinelles Lernen. Gegenstand ist die auf den mittelfristigen Zeithorizont bezogene Ressourcenplanung von Knoten des Schienengüterverkehrs, die sogenannte taktische Planung. Diese spielt eine wesentliche Rolle für eine wirtschaftliche und qualitativ hochwertige Betriebsdurchführung. Knoten des Schienengüterverkehrs stellen neuralgische Punkte in der Transportkette von Waren auf der Schiene dar. Sie dienen der Durchführung einer Vielzahl unterschiedlicher betrieblicher Prozesse zur Sicherstellung eines definierten Outputs an Zügen in Abhängigkeit eines jeweils gegebenen Inputs. Die Bereitstellung eines zu den Betriebsanforderungen passenden Ressourcengerüsts ist Teil der taktischen Planung und hat wesentlichen Einfluss auf die Qualität der Prozesse in den Knoten, im Speziellen, sowie auf die vor- und nachgelagerte Transportdurchführung im Allgemeinen. Die Bemessung des notwendigen Personals, der Betriebsmittel und der Infrastruktur für einen Betriebstag, die sogenannte Ressourcendimensionierung, ist in der Praxis geprägt durch einen erheblichen manuellen Aufwand sowie eine große Abhängigkeit von der Datenqualität. Vor diesem Hintergrund und zur Überwindung dieser Nachteile schlägt diese Dissertation ein neues Verfahren zur Ressourcendimensionierung vor. Exemplarisch wird der Fokus auf die großen Knoten des Einzelwagenverkehrs gelegt, die sogenannten Rangierbahnhöfe. In diesen werden Eingangszüge zerlegt, Güterwagen entsprechend ihrer Ausgangsrichtung sortiert und gesammelt, sowie neue Ausgangszüge gebildet und bereitgestellt. Nach dem Stand der Technik werden für die Ressourcendimensionierung mehrere Monate bis wenige Wochen vor der Betriebsdurchführung Rangierarbeitspläne erstellt. Diese umfassen einen detaillierten Arbeitsfolgenplan inklusive Terminierung von Prozessen sowie deren Ressourcenbelegung. Die Rangierarbeitspläne bilden die Grundlage für die Ressourcenanforderung. Aufgrund sich ändernder Nebenbedingungen vor dem Betriebstag und dem stochastischen Charakter der Betriebsprozesse sowohl im Netz als auch in den Knoten können die in der taktischen Planung erstellten Rangierarbeitspläne nur begrenzt für die Durchführung verwendet werden. Als Beispiele sollen das Einlegen von Sonderzügen, Unregelmäßigkeiten bei den Transporten und Witterungsauswirkungen angeführt werden. Der betriebene Planungsaufwand begründet sich in den komplexen Zusammenhängen zwischen den Betriebsprozessen und der größtenteils fehlenden EDV-Unterstützung, was eine Ermittlung der Ressourcendimensionierung bisher erschwert. Die Folge ist eine Diskrepanz zwischen der Datenqualität als Eingangsgröße für die Planung und der Präzision des Rangierarbeitsplans als Ausgangsgröße, was als Konsequenz eine Scheingenauigkeit der Planung und unter Umständen eine Über- oder Unterdimensionierung der Ressourcen mit sich bringt. Das zeigt, dass die Planung verkürzt werden muss und neue Hilfsmittel erforderlich sind. Motiviert durch diese Diskrepanz und den neuen Möglichkeiten, die die Methoden aus den Bereichen des Operations Research und des Maschinellen Lernens bieten, stellt diese Dissertation ein neues Planungsverfahren Parabola bereit. Parabola ermittelt mit geringerem Planungsaufwand und hoher Qualität relevante Kenngrößen für die Ressourcendimensionierung in Knoten des Schienengüterverkehrs. Dies beschleunigt den taktischen Planungsprozess, reduziert Scheingenauigkeiten bei der Ressourcendimensionierung vor der Betriebsdurchführung und orientiert sich daran, wann welche Entscheidungen zuverlässig und genau zu treffen sind. Folglich wird die Detailtiefe der Planung mit der Zuverlässigkeit der Daten in Einklang gebracht. Das in der Dissertation bereitgestellte Planungsverfahren Parabola analysiert eine ausreichend große Anzahl errechneter Rangierarbeitspläne und / oder historischer Betriebsdaten. Das dabei trainierte Regressionsmodell wird anschließend zur Bestimmung des Ressourcengerüsts genutzt. Die Kalibrierung der Regressionsmodelle erfordert hinreichend viele Rangierarbeitspläne. Für deren Erzeugung wird exemplarisch am Beispiel von Rangierbahnhöfen in dieser Dissertation ein ganzheitliches mathematisches lineares Programm entwickelt, das erstmalig sämtliche für die taktische Planung eines Rangierbahnhofs relevanten Entscheidungsprobleme vom Zugeingang bis zum Zugausgang abbildet. Dieses beinhaltet die Definition der Verknüpfung zwischen Eingangs- und Ausgangszügen, sogenannter Wagenübergänge, sowie die Terminierung sämtlicher Betriebsprozesse mit ihrer Zuweisung zu örtlichen Mitarbeitern, Betriebsmitteln und Infrastruktur. Die bestehenden mathematischen Modelle in der bisherigen Literatur beschränken sich lediglich auf Teile dieses Problems. Es folgt die systematische Erzeugung von Problemstellungen, sogenannten Instanzen, zur Generierung eines repräsentativen Testpools. Die Instanzen dieses NP-schweren Problems sind für generische, exakte Lösungsverfahren in akzeptabler Zeit nicht zuverlässig lösbar. Daher wird eine maßgeschneiderte Metaheuristik, konkret ein Verfahren der Klasse Adaptive Large Neighborhood Search (ALNS), entwickelt. Diese bewegt sich durch den Lösungsraum, indem schrittweise mittels mehrerer miteinander konkurrierender Subheuristiken eine vorher gefundene Lösung erst zerstört und anschließend wieder repariert wird. Durch unterschiedliche Charakteristika der Subheuristiken und einer statistischen Auswertung ihres jeweiligen Beitrags zum Lösungsfortschritt, gelingt es der ALNS, sich an das Stadium der Lösungssuche und an die jeweilige Problemstruktur anzupassen. Die in dieser Dissertation entwickelte ALNS erzeugt für realistische Instanzen eines Betriebstages Lösungen in hoher Qualität binnen weniger Minuten Rechenzeit. Basierend auf den erzeugten Rangierarbeitsplänen wurden für die Entwicklung des Planungsverfahrens insgesamt fünf Regressionstechniken getestet, die die Ausgangsgrößen der Pläne – Bedarf an Lokomotiven, Personal und Infrastruktur – prognostizieren. Die vielversprechendsten Ergebnisse werden durch die Methoden Tree Boosting sowie Random Forest erzielt, die in über 90 % der Fälle den Ressourcenbedarf für Personale und Lokomotiven exakt und für Infrastruktur mit einer Toleranz von einem Gleis je Gleisgruppe prognostizieren. Damit ist dieses Regressionsmodell nach ausreichender Kalibrierung entsprechend örtlicher Randbedingungen geeignet, komplexere Planungsverfahren zu ersetzen. Die Regressionsmodelle ermöglichen die Abstrahierung von Mengengerüsten und Leistungsverhalten von Knoten des Schienengüterverkehrs. Daher ist beispielsweise ein konkreter Fahrplan von und zu den Knoten nicht mehr notwendige Voraussetzung für die taktische Planung in Rangierbahnhöfen. Da das Regressionsverfahren aus vielen Rangierarbeitsplänen lernt, verringert sich die Abhängigkeit von einzelnen Instanzen. Durch die Kenntnis von vielen anderen Plänen können robustere Ressourcengerüste prognostiziert werden. Neben dem in dieser Dissertation ausgearbeiteten Anwendungsfall in der taktischen Planung in Knoten des Schienengüterverkehrs, eröffnet das vorgeschlagene neue Planungsverfahren Parabola eine Vielzahl an weiteren Einsatzfeldern. Die Interpretation des trainierten Regressionsmodells erlaubt das tiefgründige Verständnis des Verhaltens von Knoten des Schienengüterverkehrs. Dies ermöglicht ein besseres Verstehen der Engpässe in diesen Knoten sowie die Identifikation relevanter Treiber der Ressourcendimensionierung. Weiter können diese Modelle bei der Erstellung von netzweiten Leistungsanforderungen Berücksichtigung finden. Mit der in dieser Dissertation erfolgten Bereitstellung von Parabola wird durch Nutzung neuartiger Methoden aus dem Operations Research und Maschinellen Lernen das Instrumentarium der eisenbahnbetriebswissenschaftlichen Verfahren und Modelle sinnvoll erweitert. / This dissertation combines the knowledge of railway operations management with methods from operations research and machine learning. It focuses on rail freight facilities, especially their resource planning at a tactical level. The resource planning plays a crucial role for economical operations at high quality. The rail freight facilities represent neuralgic points in the transport chain of goods by rail. Their task is to carry out a multitude of different operational processes to ensure a defined output of trains, depending on a given input. Providing resource requirements appropriate to the amount of work has a significant impact on the quality of the processes in the facilities in particular and on the up- and downstream transport performance in general. The correct dimensioning of resource requirements, which include the necessary staff, locomotives, and infrastructure for an operating day, is characterized by a considerable manual effort and a large dependency on the data accuracy. Against this background and to overcome these drawbacks, this dissertation proposes a new method for resource requirements. The focus is on the large facilities of single wagonload traffic, the so-called classification yards, in which inbound trains are disassembled, railcars are classified according to their outbound direction, and new outbound trains are formed. Nowadays, shunting work plans are created several months to a few weeks before operations. These operating plans comprise a detailed work sequence plan, including process scheduling, and resource allocation. The operating plans form the basis for resource requirements. Due to the changing constraints prior to operations, e.g., the addition of special trains, and the stochastic nature of the operational processes, for instance caused by weather conditions, shunting work plans can only be used for execution to a limited extent. This effort is made for planning due to the complex interdependencies between the operational processes and the predominant lack of IT support, which makes it difficult to determine resource requirements. The result is a discrepancy between the accuracy of the data as an input variable and the precision of the shunting work plan as an output variable. This leads to an illusory precision of the planning and possibly to an oversizing or undersizing of the resources. Hence, planning must be shortened and new tools are required. Motivated by this discrepancy and the new possibilities offered by methods from the _elds of operations research and machine learning, this dissertation provides a new planning method Parabola. Parabola determines with less planning effort and at high quality relevant parameters for resource requirements in rail freight facilities. This accelerates the planning process, reduces illusory precision before operations are carried out and enables decision-making with sufficient reliability due to the data accuracy. Consequently, the level of detail of the planning is harmonized with the reliability of the data. The planning procedure Parabola involves the analysis of numerous calculated operating plans and / or historical operating data. This trains a regression model that can then be used to determine the resource requirements. The calibration of the regression models requires many operating plans. For their generation, an integrated mathematical linear program is developed in this dissertation using the example of classification yards; for the first time, one program covers all relevant decision problems of tactical planning in a classification yard, from the train arrival to the train departure. This includes the definition of the connection between inbound and outbound trains, so-called railcar interchanges, as well as the scheduling of all operational processes with their assignment to local staff, locomotives, and infrastructure. All existing mathematical models in the literature are limited to parts of the problem. Thereafter follows a systematic generation of a test pool of problems named instances. The instances of this NP-hard problem cannot be reliably solved within an acceptable time frame with general-purpose solvers. Therefore, a tailored metaheuristic, namely an adaptive large neighborhood search (ALNS), is developed. It moves through the solution space by first destroying and then repairing a solution stepwise. Several competing subheuristics are available for this purpose. The ALNS combines multiple subheuristics, which have different characteristics and contribute to the solution progress, as determined by statistical evaluation. Consequently, the ALNS successfully adapts to the progress of the solution and to the problem structure. The ALNS, which is developed in this dissertation, generates high-quality solutions for realistic instances of an operating day in a few minutes of computing time. Based on the generated operating plans, five regression methods predicting the output variables of the operating plans – demand for locomotives, staff, and infrastructure – are tested. The most promising results are achieved by the methods tree boosting and random forest, which predict the resource requirements in over 90% of the cases for staff and locomotives accurately and for infrastructure with a tolerance of one track per bowl. Thus, a regression model can replace the more complex planning procedures after sufficient calibration according to local restrictions. The regression models allow the abstraction of quantity structures and performance behavior. Hence, for example, a dedicated timetable is no longer a prerequisite for tactical planning in classification yards. Since regression methods learn from many operating plans, the dependence on individual instances is reduced. By knowing many other plans, the regression model can predict robust resource requirements. In addition to the use case in tactical planning in rail freight facilities, the proposed new planning method Parabola opens a multitude of further _elds of application. By interpreting the trained regression model, the behavior of rail freight facilities can be understood in depth. Under certain circumstances, this allows a better understanding of the bottlenecks in these facilities and the relevant drivers of resource dimensioning. Furthermore, these models have potential applications in the design of network-wide performance requirements. By providing Parabola in this dissertation, the toolbox of railroad management science procedures and models is sensibly extended by using novel methods from operations research and machine learning.
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Olfactory Approaches to Historical Study: The Smells of Chicago's Stockyard Jungle, 1900-1910

McNulty, Christine January 2009 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / As historians have expanded their interests from focusing on great men and groundbreaking events to perspectives that explore everyday experiences or ordinary people, odor emerges as an important interpretative lens. Understanding the olfactory history of communities, especially what types of odors were present and how people perceived and reacted to them, enlarges historians’ understanding of the life experiences and behaviors of people in the past. The historical study of odor provides insights into how quality of life and standards of living have changed over time. Understanding how people of different times reacted to odors suggests how they perceived the sensory world around them, including people living close by. In this thesis, I examine the olfactory conditions of the neighborhood surrounding the Union Stockyards and associated meat processing facilities on Chicago’s south side in the first decade of the twentieth century. During this period, an overpowering combination of putrid odors characterized this neighborhood, known as Back of the Yards. Various factors contributed to this malodorous “smellscape,” and it impacted the quality of life of the predominantly immigrant communities that made up the workforce and residents of that neighborhood.

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