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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.
81

Infrastructure development in economic crisis and recovery : the rail cargo sector in Zimbabwe since 2000.

Takundwa, Dianah Rumbidzai. 23 September 2014 (has links)
The study sought to investigate infrastructure development in economic crisis and recovery, with specific regard to the rail cargo sector in Zimbabwe since 2000. The research was prompted by firstly, the need to assess the current situation of the National Railways of Zimbabwe (NRZ), secondly, to examine the root cause of the challenges being faced by the National Railways of Zimbabwe and lastly, to review the plans going forward to resolve the challenges. In the study, a sample of 17 respondents was selected. Questions were used to guide the interview schedule. The data was collected through semi-structured interviews and was presented and analysed using thematic analysis. The findings were then interpreted in relation to research objectives and questions. The research findings showed that most of the challenges that were being experienced by the National Railways of Zimbabwe were as a result of the economic meltdown of the Zimbabwean economy. It is evident from the findings that the rail cargo in Zimbabwe can be improved if the parastatal can be given autonomy to run the day to day operations without political interference from the government. The results further suggest that the National Railways of Zimbabwe can be in a position to breakeven or become financially viable if the government, who is the major shareholder, opens up lines or credit and helps secure strategic partners who will bring in capital. In light of the above findings, the study recommends that the government explore more private sector participation and private concession options as this will help the National Railways of Zimbabwe improve its current challenges. Secondly, the 1997 Railway Act has to be signed and officialised so as to enable the organisation to operate commercially. Thirdly, the staff composition and the election of the Board of Directors should be revisited so as to engage to stakeholders in promoting transparency, integrity and efficiency. Lastly, the National Railways of Zimbabwe needs to revive its Railway Motor Services Private Limited because it will help the organisation to cut down on competition from the road sector. / Thesis (M.Dev.Studies)-University of KwaZulu-Natal, Durban, 2014.
82

Rehabilitation Of Malatya Narli No: 7 Railroad Tunnel

Divleli, Baris 01 September 2004 (has links) (PDF)
In thesis thesis, studies associated with the rehabilitation of the Malatya-Narli No: 7 Railroad Tunnel are presented. The rehabilitation work includes cleaning of two collapses and stopping of deformations occurring in the tunnel as well as characterizing the rock-mass by evaluating the cores obtained from 67 drill holes. Due to two collapses ocurred in the tunnel a large sinkhole (15x10x20 meters) was developed at the surface and the tunnel closed to train traffic for 10 months (September, 2002-July, 2003) covering the initiation of Iraq War. Originally, the tunnel had been opened into the paleo-landslide material in 1930. The rock-mass surrounding the tunnel consists of limestones, metavolcanics, and schists. Although the main problem in the tunnel is the reduced tunnel span caused by displacements triggerred by underground water, poor rock mass and time dependent deformations, from engineering point of view the other problems can be sited as collapses occurred in the tunnel, sinkhole devoloped at the surface and unstable sections existing in the tunnel. During the field studies, 15 deformation monitoring stations were installed aimed at determining the deviation from tunnel alignment. In order to provide stability of the tunnel Self Drilling Anchors (Mai bolts) were installed systematically around the tunnel. The details of the rock reinforcement design was presented in this thesis.
83

An evaluation of the role of the mass transit railway system in the urban development of Hong Kong 1979-1996 /

Lam, Kwok-chun. January 1997 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 150-162).
84

Congestion theory and railway traffic /

Lerz, Stefan. January 1996 (has links)
Thesis (doctoral)--Rijksuniversiteit Groningen), 1996. / In English, with summary in Dutch.
85

The impact of Mass Transit Railway on land development in Hong Kong an analysis of the island line using expansion method /

Lee, Sui-chun, Macella. January 1989 (has links)
Thesis (M.Soc.Sc.)--University of Hong Kong, 1989. / Also available in print.
86

Παραδείγματα μέτρων αντικεραυνικής προστασίας σε ηλεκτρικούς σιδηρόδρομους / Lightning protection meausures in electric railways

Αυγέρης, Σταύρος 07 June 2010 (has links)
Το θέμα της παρούσας διπλωματικής εργασίας είναι η αντικεραυνική προστασία όσον αφορά τα κυκλώματα γραμμής των ηλεκτρικών σιδηροδρομικών συστημάτων. Προτού όμως αναφερθούν τρόποι και συσκευές προστασίας ή δoθούν κάποια παραδείγματα εφαρμογών στις σιδηροδρομικές γραμμές κάποιων χωρών, πρέπει να γίνει μια εισαγωγική αναφορά γύρω από τον πυρήνα αυτής της εργασίας: τον κεραυνό. Έτσι, στο 1 κεφάλαιο γίνεται περιγραφή κάποιων εισαγωγικών εννοιών σχετικά με τον κεραυνό. Ξεκινώντας από τη φόρτιση των σύννεφων και στο πως αυτή γίνεται, καταλήγουμε στα διάφορα είδη κεραυνών. Ακολουθεί η εξομοίωση στο εργαστήριο με ορισμένα μεγάλα διάκενα εκκένωσης για την εξαγωγή κάποιων συμπερασμάτων της εκκένωσης του κεραυνού. Στη συνέχεια αναλύεται ο μηχανισμός των ατμοσφαιρικών εκκενώσεων μέσα από τρεις φάσεις: έναρξη οχετού (οχετός προεκκένωσης), φάση του οχετού επιστροφής και ο συνδετικός οχετός. Τέλος γίνεται ανάλυση του ρεύματος κεραυνού και των παραμέτρων του, ενώ δίνονται και κάποιες σχέσεις για τη συχνότητα εμφάνισης των κεραυνών. Στο 2 κεφάλαιο γίνεται ανάλυση των συνδέσεων ασφαλειών (fuse link), μιας εφαρμογής που χρησιμοποιείται για την αντικεραυνική προστασία των κυκλωμάτων γραμμής. Αρχικά γίνεται περιγραφή των ειδικών παραμέτρων του συστήματος της συγκεκριμένης εφαρμογής που χρησιμοποιείται στα κινητήρια συστήματα. Στη συνέχεια δίνεται μια σύντομη επισκόπηση του πλήρους σχεδίου. Ακολούθως περιγράφονται οι προσομοιώσεις υπολογιστών, στις οποίες καθορίστηκε η κατανομή του ρεύματος κεραυνού σ’ ένα κινητήριο σύστημα. Στην παράγραφο 2.1.3.δ, εξηγείται η εργαστηριακή δοκιμή της συσκευής περιορισμού της τάσης, ειδικά της συμπεριφοράς (με τη χαρακτηριστική) του ρεύματος κεραυνού. Επιπλέον, γίνεται περιγραφή της πρακτικής εφαρμογής των ασφαλειών που είναι ανθεκτικές σε κεραυνούς, παρουσιάζοντας μια πρακτική δοκιμή. Δίνονται επίσης ορισμένες τυποποιημένες εφαρμογές. Τέλος, εξηγείται το σχέδιο των συνδέσεων των ασφαλειών που είναι ανθεκτικές σε κεραυνούς. Στο 3 κεφάλαιο αναλύονται τα αλεξικέραυνα μεταλλικών οξειδίων (ΜΟ). Τα συστήματα ισχύος των ηλεκτρικών σιδηρόδρομων μπορούν να προστατευτούν έναντι υπερτάσεων με τη χρήση αυτών των συσκευών. Στο κεφάλαιο περιγράφεται η αρχή λειτουργίας των αλεξικέραυνων ΜΟ, η οποία βασίζεται στη μη γραμμική χαρακτηριστική τάσης - ρεύματος συγκεκριμένων κεραμικών στοιχείων, αποκαλούμενα MO varistors. Ακολουθούν οι τρεις τύποι αλεξικέραυνων υπέρτασης ΜΟ για τα ηλεκτρικά συστήματα σιδηρόδρομων: με περίβλημα πορσελάνης, με συνθετικό πολυμερές περίβλημα και με άμεσα διαμορφωμένο πολυμερές περίβλημα. Τέλος, γίνεται λόγος για τη χρήση των αλεξικέραυνων ΜΟ στα DC κινητήρια συστήματα σύμφωνα με την Ένωση των Γερμανικών Επιχειρήσεων Μεταφορών (VDV), σε διάφορες σιδηροδρομικές εφαρμογές. Στο 4 κεφάλαιο γίνεται ανάλυση ενός πλάνου αντικεραυνικής προστασίας για τα συνεχούς ρεύματος (DC) σιδηροδρομικά συστήματα. Αρχικά, γίνεται μια αναφορά στις τάσεις του συστήματος και τις διάφορες μορφές υπερτάσεων, των άμεσων και έμμεσων πληγμάτων κεραυνού. Στη συνέχεια περιγράφονται κάποιες συσκευές προστασίας (καθώς και τα χαρακτηριστικά αυτών), όπως είναι τα αλεξικέραυνα υπερτάσεων ΜΟ (τύπου Α1 και Α2), οι περιοριστές χαμηλής τάσης (LVL), ενώ εισάγεται ένας προσφάτως ανεπτυγμένος υβριδικός περιοριστής τάσης (HVL) ο οποίος συνδυάζει την προστασία από υπερτάσεις και την προστασία έναντι των επικίνδυνων τάσεων επαφής. Τέλος, γίνεται μία περιγραφή διαφόρων μέτρων προστασίας στις γραμμές μεταφοράς, στους υποσταθμούς καθώς επίσης και στα οχήματα κίνησης, ενώ δίνονται και κάποια αποτελέσματα δοκιμών με χρήση LVLs. Το 5 κεφάλαιο αναλύει την πρόβλεψη των σφοδρών εκκενώσεων κεραυνού που μπορούν να προκαλέσουν μια σοβαρή διαταραχή στη λειτουργία της αμαξοστοιχίας, με τη χρησιμοποίηση υπολογιστών βασισμένων στο Ιαπωνικό Δίκτυο Ανίχνευσης Κεραυνού (Japanese Lightning Detection Network - JLDN), προκειμένου να υποστηρίξουν πομπούς για να κάνουν μια αποτελεσματική λήψη απόφασης σχετικά με τη ρύθμιση των μηχανικών συντήρησης, τις γεννήτριες ηλεκτρικής ενέργειας έκτακτης ανάγκης και τις επιπλέον ηλεκτρικές συσκευές για γρήγορη ανάκτηση. Ένα πραγματικού χρόνου σύστημα υποστήριξης λήψης απόφασης έχει αναπτυχθεί. Τέλος, γίνεται αναφορά στις δύο κύριες τεχνικές εκτίμησης, που εχουν αποτιμηθεί με την εφαρμογή τους σε πραγματικά δεδομένα κεραυνού, οι οποίες χρησιμοποιούνται για την εκτίμηση της τροχιάς της περιοχής που κινείται επικίνδυνα και της διάρκειας της δραστηριότητας του κεραυνού. Στο 6 κεφάλαιο περιγράφονται οι λεπτομέρειες του αισθητήρα υπερτάσεων/υπερρευμάτων κεραυνού για το σιδηρόδρομο. Πρόκειται για ένα νέο σύστημα ελέγχου του σιδηροδρομικού σήματος, το οποίο ελέγχει σιδηροδρομικά σήματα, διακόπτες, κυκλώματα γραμμής βασισμένα στο πρωτόκολλο IP. Σε αυτό το σύστημα, πολλές ηλεκτρονικές συσκευές εγκαθίστανται κατά μήκος του σκληρού περιβάλλοντος του σιδηροδρόμου. Επομένως, αυτές οι ηλεκτρονικές συσκευές πρέπει να έχουν αντοχή προς το περιβάλλον για υπέρταση/υπέρρευμα κεραυνού, για θερμοκρασία, για δόνηση, για βροχή και για ηλεκτρομαγνητικό θόρυβο. Σαν αντίμετρο για την υπέρταση κεραυνού, χρησιμοποιούμε την προστατευτική συσκευή (το αλεξικέραυνο). Η υποβάθμιση της προστατευτικής συσκευής μπορεί να προκαλέσει την καταστροφή των ηλεκτρικών συσκευών. Έτσι αναπτύχθηκε ο αισθητήρας υπερτάσεων/υπερρευμάτων για την ανίχνευση της υποβάθμισης της προστατευτικής συσκευής. Στο 7 κεφάλαιο περιγράφονται οι μετρήσεις των υπερτάσεων και των μεταβατικών ρευμάτων κεραυνού που εισέρχονται σε μια εγκατάσταση σιδηροδρόμου κατά τη διάρκεια του καλοκαιριού του 2003 στο Tierp της Σουηδίας. Οι μετρήσεις υπερτάσεων έγιναν σε μια τεχνητή βάση που παρέχει έναν αδιάκοπο εφοσδιασμό για τα τηλεπικοινωνιακά συστήματα και τα συστήματα σηματοδότησης. Επίσης παρουσιάζονται και συζητούνται τα παραδείγματα των κυματομορφών των μεταβατικών ρευμάτων. Τέλος, το κεντρικό μήνυμα που περνάνε τα δύο τελευταία κεφάλαια, 8 και 9, είναι ότι πρέπει να ενισχυθούν τα αποτελεσματικά και οικονομικά αντίμετρα για την παρεμπόδιση των ζημιών κεραυνού στο σιδηροδρομικό σύστημα σηματοδότησης. Στο 8 κεφάλαιο μετρήθηκε η κατανομή του δυναμικού του κρασπέδου εδάφους όταν προκλήθηκε μια αύξηση δυναμικού της ράγας με την έγχυση ενός υπερρεύματος κεραυνού σε μια ράγα. Επιπλέον, διοχετεύθηκε ένα υπέρρευμα κεραυνού μέσα στη ράγα ή στο κράσπεδο εδάφους για να αυξηθεί το δυναμικό τους, προκειμένου να μετρηθούν οι υπερτάσεις κεραυνού σε μια ισόπεδη διάβαση έτσι ώστε να μπορέσουν να λάβουν βασικά δεδομένα για το σχεδιασμό της μόνωσης. Τέλος, αποδεικνύεται ότι ένα αποτελεσματικό αντίμετρο είναι να γειώσουμε τις συσκευές αντικεραυνικής προστασίας που συνδέονται με τους ηλεκτρονικούς ανιχνευτές τραίνων σε μια ισόπεδη διάβαση προκειμένου να κατασταλούν οι υπερτάσεις κεραυνού στην ισόπεδη διάβαση. Στο 9 κεφάλαιο μετρήθηκαν οι υπερτάσεις κεραυνού που προκλήθηκαν από την εισβολή των κυμάτων κεραυνού στο σιδηροδρομικό σύστημα ισόπεδης διάβασης, στην περίπτωση ενός πραγματικού πλήγματος κεραυνού, ώστε να μπορούν να κατανοηθούν οι υπερτάσεις αυτές ποσοτικά. Έτσι θα μπορούσαμε να διευκρινίσουμε τη συχνότητα εμφάνισης των υπερτάσεων κεραυνού στο σύστημα της ισόπεδης διάβασης στην κατάσταση του πραγματικού πλήγματος κεραυνού. / The subject of this project is the lightning protection for track circuits of electrical railway systems. But before being reported ways and protection devices or given some examples of applications for rail lines in some countries, should be an introductory reference around the core of this work: the lightning. Thus, chapter 1 contains a description of some import concepts about lightning. Starting from the charge of the clouds and how it is, we arrive at the different types of lightning. Here the simulation in the laboratory with some major gaps evacuation for some of the conclusions of the lightning discharges. Then analyze the mechanism of atmospheric discharges through three phases: entry drain, phase of the return drain and the connecting drain. Finally an analysis of lightning current and his parameters became, while some relationships are given about occurrence frequency of lightning. In the 2nd chapter an analysis of fuse link, an application used for lightning protection on track circuits, is described. First the special system parameters for this specific application, used in traction systems will be described. Then a brief overview of the complete project is given. Following computer simulations will be described, in which the lightning current distribution in a traction system was determined. In the paragraph 2.1.3.δ, the laboratory testing of the voltage limiting device, especially its lightning current behavior is explained. Moreover the practical application of the lightning resistant fuse link both in a field test and following in stand applications is described. Finally the design of this lightning resistant fuse link is explained. In the 3rd chapter Metal-Oxide (MO) surge arresters are described. Power systems of electric railways may be protected against overvoltages by using them. The operating principle of an MO surge arrester is essentially based on the strongly non-linear current-voltage characteristic of specific ceramic elements, so-called MO varistors, is described. Following the three types of (MO) surge arresters for electrical railway systems: with a Porcelain Housing, with a Polymer Composite Housing and with a Directly Moulded Polymer Housing. Finally, talk about use of MO surge arresters in DC traction systems as per Association of German Transport Undertakings (VDV), in various railway applications. In the 4th chapter an overvoltage protection concept for DC railway systems, is analyzed. First, there is a reference about system voltages and on various forms of overvoltages, of direct and indirect lightning strokes. Below, some protection devices (and their characteristics), such as the (MO) lightning surge arresters (A1 and A2 type), the Low Voltage Limiters (LVLs), while a newly developed Hybrid Voltage Limiter (HVL), which combines overvoltage protection and the protection against dangerous touch voltages, is introduced, are quoted. Finally, a description about some protection measures on overhead lines, for substations, and also on traction vehicles, while some test results using LVLs, are given. The 5th chapter investigates the prediction of severe lightning discharges that might cause a serious disturbance in train operation, by using computers based on the Japanese Lightning Detection Network (JLDN), in order to support dispatchers to make an effective decision about arranging maintenance engineers, emergency electrical power generators and extra electrical devices for quick recovery. A real-time decision support system has been developed. Two principal estimation techniques, which are used for estimating the trajectory of moving hazardous area and the lifetime of the lightning activity, have been evaluated by applying them to the real lightning data. In the 6th chapter details of the lightning surge sensor for railway are described. This is a new railway signal control system, which controls railway signals, switches, track circuits based on IP protocol. In this system, much electronic devices are installed along harsh railway environment. Therefore, these electronic devices must have environment resistance for lightning surge, temperature, vibration, waterproof, and electromagnetic noise. As a countermeasure for the lightning surge, we utilize the protective device (cable arrester). The degradation of the protective device may cause the damage of the electric devices. So we develop a lightning surge sensor to detect the degradation of a protective device. In the 7th chapter the measurements of lightning transients entering a railway facility during the summer of 2003, in Tierp, Sweden, are described. The measurements of the transients were made in a technical house that supplies an uninterrupted supply for the telecommunication systems and the signal systems. Examples of transient waveforms are presented and discussed. Finally, the major idea of chapters 8 and 9 is that it’s required to build up effective and economical countermeasures for preventing lightning damages on the railway signalling system. In the 8th chapter the wayside ground potential distribution when a rail potential rise was caused by injecting a lightning surge current into a rail, are measured. Moreover, a lightning surge current into the rail or wayside ground is injected, to raise their potential, in order to measure the lightning overvoltages on a level crossing so that we can obtain basic data for insulation design. It is shown in the paper that an effective countermeasure is to earth lightning protective devices attached to electronic train detectors for a level crossing in order to suppress the lightning overvoltages on the level crossing. In the 9th chapter the lightning overvoltages caused by invading lightning surges into the railway level crossing system in the event of real lightning stroke so that we can grasp the lightning overvoltages quantitatively, are measured. So, we could clarify the occurrence frequency of lightning overvoltages on the level crossing system in the condition of the real lightning stroke.
87

FIM DO PRAGMATISMO: AS RELAÇÕES ENTRE ESTADO E OS FERROVIÁRIOS EM SANTA MARIA/RS DURANTE O PRIMEIRO PERÍODO DA DITADURA CIVIL-MILITAR NO BRASIL (1964-1968) / END OF PRAGMATISM: RELATIONS BETWEEN THE STATE AND THE RAILWAYS IN SANTA MARIA / RS DURING THE FIRST PERIOD OF CIVIL-MILITARY DICTATORSHIP IN BRAZIL (1964-1968)

Berni, Antonio Augusto Durgante 30 March 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aims to examine the relationship between the State and railroad workers of Santa Maria during the first period of the Civil-Military Dictatorship in Brazil between 1964 and 1968. Given this, we seek to establish the main line of work as the idea that in this period due to the violent repression that followed mainly against the most active class-leaders, the pragmatism that characterized the political praxis of the railways during the so-called populist state (1945 -1964) came to an end. Likewise, the role of representative organizations scattered in associations, unions, etc. lost his sense of being due to policy interventions suffered at the summit which led to a depoliticization of workers and take a role especially bureaucratic in relation to conflicts at work. Thus, the railways have been jettisoned not only their influence on the other professional categories in the city, as well as the various spheres of power which had representatives. The issue of torture against political prisoners in Santa Maria was another important issue that has examined and direct connection with the practice intervention and demobilization class carried out by the authoritarian regime that was imposed in the country from 1964. / O presente estudo visa examinar as relações entre o Estado e os trabalhadores ferroviários de Santa Maria durante o primeiro período da Ditadura Civil-Militar brasileira, entre 1964 e 1968. Diante disto, procuramos estabelecer como linha principal do trabalho a ideia de que neste período devido à violenta repressão que se seguiu principalmente contra os líderes classistas mais atuantes, o pragmatismo que caracterizou a práxis política dos ferroviários durante o período do assim chamado Estado populista (1945-1964) chegou ao fim. Da mesma forma, a atuação dos organismos representativos dispersos em associações, uniões, etc., perdeu seu sentido de ser devido às intervenções sofridas na cúpula diretiva o que levou a uma despolitização do meio classista e a assumirem uma feição notadamente burocrática em relação aos conflitos do trabalho. Sendo assim, os ferroviários foram alijados não apenas de sua influência sobre as demais categorias profissionais da cidade, como também das várias esferas de poder onde possuíam representantes. A questão da tortura contra os presos políticos em Santa Maria foi outra questão importante examinada e que possui ligação direta com a prática de intervenção e desmobilização classista levada a efeito pelo regime autoritário que se impôs no país a partir de 1964.
88

Metodologia de avaliação de emissões de dióxido de carbono no transporte intermodal: um estudo de caso da soja de exportação brasileira. / Methodology for evaluation of carbon dioxide emissions in intermodal transpot: a case study of brazilian soybean exports.

Rachel Jardim Medeiros da Silva 13 August 2015 (has links)
As emissões globais de dióxido de carbono cresceram em mais de 100% desde 1971 (IEA, 2013), sendo que o aumento foi mais acentuado no período entre 2000 e 2010 (IPCC, 2014). O Brasil ocupa o 13º lugar no ranking mundial dos principais países emissores de gases de efeito estufa (IEA, 2012) e, portanto, é indispensável que alternativas de redução das emissões nacionais sejam estudadas, entre elas, a adoção de modos de transporte mais sustentáveis. Apesar do modo ferroviário ser energeticamente mais eficiente que o rodoviário (ICF CONSULTING, 2009), a extensão da malha ferroviária brasileira é reduzida, sendo necessário associar o transporte ferroviário a etapas de coleta e distribuição da carga por rodovia, o que pode significar maiores gastos energéticos. Em vista disso, este trabalho teve por objetivo propor uma metodologia para estimativa da redução de emissões de dióxido de carbono por meio do transporte intermodal em comparação ao exclusivamente rodoviário. O modelo de emissões desenvolvido é versátil para aplicação em múltiplas situações, não restringindo a região brasileira de estudo e a carga ferroviária. Basicamente, é necessário conhecer o percurso utilizado, bem como o consumo de combustível em litros/tku por trecho ferroviário, além do fator de consumo de combustível médio na rodovia. A metodologia foi aplicada especificamente ao transporte de soja brasileira para exportação. O problema foi abordado em escala nacional, sendo que as origens da carga foram detalhadas por município e as distâncias rodoviárias foram calculadas com a ferramenta Google Maps. Para cada município produtor de soja foram estimadas as emissões associadas às duas alternativas de transporte, sendo a visualização dos resultados realizada por meio de heat map, elaborado em função do potencial de economia de emissões (%) de cada município. Com base nesse mapa, foram apontadas as regiões geográficas do país, onde o transporte intermodal apresenta maiores ganhos ambientais. Por fim, os resultados foram confrontados com o mapa de economias obtido por CRAIG et al. (2012) para os Estados Unidos, sendo o impacto da distância ao terminal de embarque e da distância total da rota na economia de emissões analisado. / Global carbon dioxide emissions have more than doubled since 1971 (IEA, 2013), increasing at a higher rate between 2000 and 2010 (IPCC, 2014). Brazil occupies the 13th position in the ranking of the worlds largest greenhouse gases emitters (IEA, 2012) and, therefore, it is essential to consider alternatives regarding emissions reduction at national level, including sustainable transport systems. Although rail is more fuel efficient than truck (ICF CONSULTING, 2009), the Brazilian rail network is concentrated in a few regions, requiring association of the rail transport to pre- and post-haulage by road, that might lead to higher energy consumption. Thus, this research aimed to develop a methodology to estimate the potential reduction of carbon dioxide emissions due to intermodal transportation when compared to trucking. The emissions model is versatile in terms of possible applications, since it is not restricted to a specific Brazilian region or any good type transported. Basically, it is necessary to know the general route, the fuel consumption in liter/tku for each rail stretch and the average fuel consumption factor of the truck. This method was applied specifically to the Brazilian soybean exportations. The approach of the problem was at the national level and the origins of the cargo corresponded to all the soybean producing towns. Furthermore, road distances were calculated using the Google Maps tool. For each town, emissions were estimated considering both transportation alternatives: intermodal and trucking. Then, the results were presented in a heat map, elaborated in function of the potential carbon savings (%) for each town. Based on this map, the regions where the intermodal route means environmental gains were indicated. Finally, the results were compared to the American carbon savings map created by CRAIG et al. (2012), addressing the impact of terminal distance and total distance travelled on emissions savings.
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Fim da linha? Vilas ferroviárias da Companhia Paulista (1868-1961): uma investigação sobre história e preservação / End of the line? Railway worker villages of Companhia Paulista (1868-1961): a research about history and preservation

Luciana Massami Inoue 21 February 2017 (has links)
O propósito desta pesquisa foi estudar a história social das vilas ferroviárias da Companhia Paulista e contribuir para a discussão sobre a preservação das mesmas. Dentre as diversas companhias ferroviárias espalhadas pelo estado de São Paulo, elegeu-se a Companhia Paulista, a primeira formada com capital nacional e com grande penetração geográfica, política, econômica e social. E dentre as suas vilas, foram escolhidas somente seis como estudo de caso - Itirapina, Brotas, Dois Córregos, Jaú, São Carlos e Rincão - ainda não analisadas, e que apresentavam um número considerável de casas e se localizavam geograficamente próximas, no \"coração\" do estado de São Paulo. O recorte temporal é o da própria Companhia que inicia-se em 1868, e termina em 1961, como empresa privada. Como métodos empregados a pesquisa utilizou- se de fontes primárias - especialmente os Relatórios da Companhia Paulista - e como fontes secundárias, houve duas vertentes que se procurou conjugar: uma referente às vilas ferroviárias, a Companhia Paulista e seus trabalhadores e, outra vertente referente às questões de preservação. Foram de fundamental importância as visitas de campo às respectivas cidades, na verificação do estado de conservação, sua morfologia urbana e a aplicabilidade de propostas pensadas para sua preservação. Igualmente importantes foram às visitas técnicas realizadas para analisar e comparar o encaminhamento dado ao patrimônio industrial ferroviário e urbano nos diferentes países. As vilas ferroviárias tomadas de maneira isolada parecem ser insignificantes, contudo, ao estudar a história social da Companhia Paulista e principalmente a de seus trabalhadores, as vilas passam a adquirir outro significado. Desse modo, o valor das vilas ferroviárias é melhor entendido com a apreciação dos processos históricos mais amplos. Um dos caminhos possíveis encontrados para a re-significação encontra apoio no conceito de paisagem cultural, assim como no conceito de áreas de conservação ou conservação integrada. Os conceitos se complementam e ambos auxiliam a gestão do patrimônio. E a partir do conceito de áreas de conservação, encontra-se a leitura morfotipológica. Ao invés de uma leitura estilística das vilas ferroviárias, optou-se por fazer tal leitura, mais ligada ao tecido urbano, aliada é claro, à investigação da história social destes espaços, que acreditamos que dá sustentação e significação para uma política de preservação, na busca de encontrar o caráter do lugar, e ao mesmo tempo conectar o passado à dimensão contemporânea que devem ter as políticas de preservação. Espera-se assim ter cumprido com os objetivos, de valorizar novamente as vilas ferroviárias e o mundo do trabalho dentro da história e das políticas de preservação. / The aim of this research was to study the social history of the railway worker villages of the \"Companhia Paulista\" and to contribute to the discussion about their preservation. Among many railway companies spread in the São Paulo state, the \"Companhia Paulista\" was chosen because it was the first company to be founded with national capital and due to its geographical, political, economic and social influence. Among its villages, only six of them were chosen as cases of study - \"Itirapina\", \"Brotas\", \"Dois Córregos\", \"Jaú\", \"São Carlos\" e \"Rincão\" - villages not yet analysed, which showed a considerable number of houses and were located geographically close to each other, \"in the heart of\" São Paulo state. The time frame of the research was given by the company life time itself, with start in 1868 and end in 1961 as a private enterprise. The methods employed were the investigation of primary sources - especially the \"Companhia Paulista\" annual reports - and secondary sources, which were divided into two parts that we sought to combine: one refers to railway worker villages, the \"Companhia\" and its workers, and the other one refers to the preservation issues. The field visits to the aforementioned cities were important for the verification of their conservation status, their urban morphology as well as for the analysis of the applicability of the proposals to their preservation. The technical visits made were similarly important to analyse and compare the solution given to the industrial railway and urban heritage in different countries. Taken into an isolated view, the railway villages seem insignificant, however, as we study the accompanying social history of the \"Companhia Paulista\" and mainly of its workers, the villages acquire a whole new meaning. Thus in this way, the value of the railway worker villages is better understood with the analysis of broader historical processes. One of the possible ways found to the \"re-meaning\" is supported by the cultural landscape concept as well as the concept of conservation areas or integrated conservation. The concepts complement one another and both help in the heritage management. From the concept of conservation areas, the morphotypological analysis emerges. Instead of a stylistic analysis of the railway worker villages, we preferred the present type of analysis, more related to the \"urban fabric\" and connected to the investigation of the social history of these places, which we believe sustain and give meaning to the preservation policies, in the search of the \"character of the place\", while at the same time trying to connect the past to the contemporary dimension, which should have the preservation policies. We hope that with this research we have accomplished the following purposes: once again give value to the railway worker villages and the associated world of labour inside history and inside the preservation policies.
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Proposição de dispositivo de medidas \"in situ\" para avaliação do comportamento mecânico de lastro ferroviário: estudo de caso na Estrada de Ferro Carajás. / Proposition device measures \"in situ\" to evaluate the mechanical behavior of ballast: case study on the Estrada de Ferro Carajás.

Robson Correia da Costa 14 July 2016 (has links)
Esse trabalho tem como principal objetivo propor um dispositivo de medição de deslocamentos (deflexões) verticais para avaliar o comportamento mecânico de lastro ferroviário \"in situ\", tomando-se como estudo de caso a Estrada de Ferro Carajás (EFC). Foram feitas campanhas de medições, contemplando três segmentos com diferentes condições de lastro, a saber: colmatado, novo e desguarnecido. Avaliou-se como cada condição do lastro se comporta em função da carga imposta pelo material rodante e do número de solicitações em milhões de toneladas brutas transportadas (MTBT). Em diversas ferrovias, um parâmetro usado como indicador da resposta elástica e qualidade da via permanente é o módulo de via (u). Nessa pesquisa adotou um modelo analítico para obter tal parâmetro, além de utilizá-lo como indicador de avalição da condição estrutural da via. Além disso, em virtude dos materiais geotécnicos subjacentes ao lastro (sub-lastro e subleito) influenciarem na resposta mecânica da via, a capacidade de suporte dos mesmos também foi determinada \"in situ\" utilizando-se o Dynamic Cone Penetrometer (DCP), bem como foram verificados os deslocamentos verticais através de settlement pegs. Adicionalmente, do material amostrado do sublastro e das diferentes condições de lastro, verificou-se em laboratório que o solo possui elevada resiliência, confirmando a alta resistência verificada em campo através do DCP, enquanto que na caracterização física completa dos lastros, os resultados mostraram que as curvas granulométricas do lastro novo e desguarnecido, estão fora dos limites da faixa adotada na especificação da Vale, e que o lastro colmatado apresentou baixa porcentagem de material passante na peneira de 12,5 mm. Os resultados mostraram deslocamentos calculados através do modelo analítico próximos aos medidos, confirmando que o uso do dispositivo é viável para a obtenção de deslocamentos em campo, sendo estes posteriormente empregados na determinação do módulo de via, permitindo a definição de indicadores da condição de elasticidade ou rigidez da estrutura. Assim, o dispositivo demonstra-se uma ferramenta útil para auxiliar na manutenção ferroviária. / This work aims to propose a vertical displacement measuring device (deflections) to evaluate the mechanical behavior of railway ballast \"in situ\", using as a case study Estrada de Ferro Carajás (EFC). \"In situ\" tests were carried out in three sections with different ballast conditions fouled, fresh, recycled. It evaluated how each ballast condition behaves according to the load imposed by the rolling stock and the number of millions gross tons (MGT). In several railways, a parameter used to estimate the elastic response and quality of the permanent way is track modulus (u). In this research an analytical model for calculating this parameter was adopted, as well as using it as an indicator of structural track condition. Furthermore, because of geotechnical underlying ballast material (subballast and subgrade) that influence the mechanical response of the track, the bearing capacity was also determined \"in situ\" using the Dynamic Cone Penetrometer (DCP), as well as they were checked through vertical displacements through settlement pegs. In addition, of the sampled material in the subballast and different ballast conditions, it was found in the laboratory that the soil has high resilience, confirming the high resistance verified in the field through the DCP, whereas in the full physical characterization of the ballast, the results showed that the granulometric distribution curves of the ballast new and recycled, are outside the limits of the range adopted in the Vale specification, and than the fouled ballast presented low percentage of passing material in the 12.5 mm sieve. The results showed displacements calculated using the analytical model next to the measured, confirming that the use of the device is feasible to obtain displacements in the field, which are subsequently used in the determination of the track modulus, allowing the definition of elasticity or stiffness condition indicators of the structure. Thus, the device is shown to be a useful tool to assist railway maintenance.

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