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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.
1

Etude du suivi des wagons de fret à des fins logistiques par onde radio : impact des intérférences électromagnétiques sur le système proposé / Study of tracking of freight wagons for logistic purposes by radio wave : impact of electromagnetic interference on the proposed system

Iben Jellal, Sara 31 August 2018 (has links)
Dans le domaine du transport de fret, il est nécessaire d’assurer le suivi des wagons, d’identifier les wagons sensibles (transport de matières dangereuses, denrées périssables…) ainsi que de collecter les informations associées (contenu, poids, localisation) pour faciliter la gestion logistique. Le but de cette thèse est de proposer un système de communication sans fil à courte portée qui répond à ces besoins. Les contraintes de l’environnement ferroviaire et de l’embarqué telles que la flexibilité, le coût de l’installation, la faible consommation d’énergie, et le risque de présence de perturbations électromagnétiques rend l’insertion des technologies sans fil dans le milieu ferroviaire plus complexe. Une étude comparative des systèmes de communication existants a permis d’identifier la technologie ZigBee comme étant la plus adaptée au problème étudié. Une comparaison des différents scénarios possibles du positionnement des dispositifs ZigBee a été réalisée et validée par des mesures en présence de véhicules et de conteneurs. L’impact des perturbations électromagnétiques issues des installations d’alimentation ferroviaire et des émetteurs RF environnants, a été étudié. Une analyse d’autres types de perturbations générées intentionnellement pour nuire au système proposé à des fins malveillantes, a été également menée. / In railway freight transport, wagons tracking is necessary to identify sensitive elements (transport of hazardous materials, perishable goods ...) and the associated information (content, weight, location) could be useful for logistic management. The aim of this thesis is to propose a short-range wireless communication system, which meets these needs. The constraints of rail environment such as flexibility, technical installation difficulties, low energy consumption and the risk of electromagnetic disturbances, causes more difficulties to insert wireless technologies in railway environment. A comparative study of existing communication systems has identified the ZigBee technology as the most appropriate to design the communication between wagons and between wagon and infrastructure for the studied application. A comparison of different possibilities for positioning of ZigBee devices was carried out. Experimentations have been realized in presence of vehicles and containers. The impact of electromagnetic disturbances issued from rail power infrastructure and from surrounding RF transmitters, has been studied. Disturbances intentionally generated to damage the proposed system, have been also analyzed.
2

A typology for ‘waenhuise’ in the vernacular farm architecture of the trans-Vaal River region

Naudé, M 01 January 2010 (has links)
Abstract The word ‘waenhuis’ has become synonymous for what is also referred to as a ‘wagon shed.’ Eventually, the term will disappear as the building’s association with wagons becomes less obvious. At the same time ‘waenhuise’ will become relevant to museums and conservationists involved in the study and conservation of local vernacular architecture. Part of investigating these buildings is the creation of a typology to determine trends and building traditions associated with this building type. Spatial configuration and organization of the floor plan are useful criteria to create such a typology. Two basic types, single- and multi-space ‘waenhuise’ can be distinguished. Single-space buildings can be divided into ‘open-sided shelters’ and ‘waenhuise with walls’. Multi-space buildings are divided into those structures consisting of a core building with additions and those that are part of a dwelling. Material and building technique are less important criteria for a typology, but remain essential for the description of the architectural vocabulary of individual buildings.
3

A typology for ‘waenhuise’ in the vernacular farm architecture of the trans-Vaal River region

Naudé, M 01 January 2010 (has links)
Abstract The word ‘waenhuis’ has become synonymous for what is also referred to as a ‘wagon shed.’ Eventually, the term will disappear as the building’s association with wagons becomes less obvious. At the same time ‘waenhuise’ will become relevant to museums and conservationists involved in the study and conservation of local vernacular architecture. Part of investigating these buildings is the creation of a typology to determine trends and building traditions associated with this building type. Spatial configuration and organization of the floor plan are useful criteria to create such a typology. Two basic types, single- and multi-space ‘waenhuise’ can be distinguished. Single-space buildings can be divided into ‘open-sided shelters’ and ‘waenhuise with walls’. Multi-space buildings are divided into those structures consisting of a core building with additions and those that are part of a dwelling. Material and building technique are less important criteria for a typology, but remain essential for the description of the architectural vocabulary of individual buildings.
4

Die tradisionele wamakersbedryf in Suid-Afrika met spesifieke verwysing na die Paarl

Van der Merwe, Hennie 12 1900 (has links)
Thesis (MA)--Stellenbosch University, 1983. / ENGLISH ABSTRACT: no abstract available / AFRIKAANSE OPSOMMING: geen opsomming
5

The lives and deaths of memorials: The changing symbolism of the 1938 Voortrekker centenary monuments

Uys, Robert Benjamin January 2019 (has links)
Magister Artium - MA / This thesis is concerned with the lives and deaths of four 1938 Voortrekker Centenary Monuments. The 1938 Voortrekker Centenary saw the construction of more than 500 centenary monuments. Each one of these structures has a biography. This study will consider how monuments celebrate current regimes and ideologies instead of narratives pertaining to the past. It will explore how monuments dating from South Africa’s imperialist and apartheid pasts reflect continued inequalities in both rural and urban South African landscapes. It will also consider how monuments cement problematic and mythological versions of the past. The most infamous 1938 Voortrekker Centenary Monument is the Voortrekker Monument, designed by Gerard Moerdyk, in Pretoria. The Voortrekker Monument is important because in many ways it acts as a proxy to the hundreds of smaller 1938 Voortrekker Centenary Monuments scattered around South Africa. This study will look at how some of the theoretical frameworks concerned with the Voortrekker Monument in Pretoria can be applied to three centenary monuments in the Riebeek Valley and Durbanville in the Western Cape. This thesis will consider how perceptions of the symbolism of these monuments have changed between their construction in the late 1930s and 2018. The Afrikaner nationalistic fever that gave birth to these structures will be dissected. It will also consider how the 1938 Voortrekker Centenary Monuments symbolically changed as South Africans witnessed the disintegration of apartheid. This study will explore how these monuments have integrated into the heritage and experiential economies. It will also consider some of the anomalies relating to these structures, including hauntings. Finally, the vandalism, destruction and futures of these structures will also briefly come into question.
6

Die Wagen der Bronze- und frühen Eisenzeit in Italien

Woytowitsch, Eugen. January 1974 (has links)
Thesis--Johann Wolfgang Goethe-Universität, Frankfurt am Main, 1974. / Vita. Includes bibliographical references.
7

Framställning av en teoretisk bokningsmodell för tids- och kostnadseffektivisering av tomvagnstransporter hos ScandFibre Logistics AB / The development of a theoretical bookings model to increase time- and cost-efficiency of empty wagon transports at ScandFibre Logistics AB

Öunapuu, Anton January 2022 (has links)
ScandFibre Logistics AB (SFL) är ett logistikföretag inom järnvägsindustrin och ingår i BillerudKorsnäs-koncernen. SFL:s uppgift är att för pappersbruk ägda av BillerudKorsnäs, samt ett fåtal externa kunder, erbjuda logistiklösningar via järnväg för brukens leveranstransporter till cirka 50 olika terminaler i Europa. I samband med det interna arbetet med att strategiskt effektivisera hanteringen av vagnstransporterna syftar detta examensarbete till att ge kunskap och undersöka hur transporter av tomvagnar från svenska terminaler tillbaka till bruken kan effektiviseras med hänsyn till transport- och hyreskostnader. Information har empiriskt samlats från intervjuer med flertal av SFL:s anställda, genom deltagande observationer och inhämtade rådata från SFL:s databas. Med en deskriptiv metod kartlagdes SFL:s verksamhet i en nulägesbeskrivning som utgjorde startpunkten för examensarbetets modellskapande. Från modellskapandet presenteras examensarbetets förslag till en teoretisk bokningsmodell. Denna bokningsmodell uppnår en teoretisk tids- och kostnadseffektivisering med matematisk logik och olika strikta samt tidskänsliga bokningskriterier som genererar bokningsförslag vars prioritering ligger vid korta transportsträckor och ett tidseffektivt utnyttjande av tomvagnar som anländer till bruken enligt JIT-principen. Med anledning av att modellen byggs på antaganden och teori bör dess resultat granskas av operativ bokningspersonal innan praktisk tillämpning. / ScandFibre Logistics AB (SFL) is a logistics company operating in the railway industry and is a part of BillerudKorsnäs. SFL offers logistic solutions for railway transport of products from BillerudKorsnäs’, as well as a few other external customers’, different paper mills to roughly 50 different terminals in Europe. In conjunction with SFL:s own interest of developing the efficiency of their own operations and handling of wagon transports, this master’s thesis aims to improve knowledge and investigate how to streamline the transport of empty wagons from Swedish terminals back to the paper mills, in regards to transport and rental costs. Information have been gathered through interviews with several employees, through participating observations, and with the extraction of raw data from SFL’s database. With a descriptive method the overall operation at SFL could be outlined, serving as the base for a model development phase. This phase resulted in this thesis’ proposed bookings model for empty wagon transports. The model acquires a theoretical streamline way of booking empty wagon transports in such a manner that wagons arrive at the paper mills according to the JIT-principle. The model succeeds in doing this by generating booking proposals using mathematical logic and time-sensitive booking criteria, with the focus being transports of short distances; in theory also meaning a time efficient use of each wagon. As the model is theoretically constructed and relies on several generalizing assumptions, its booking proposals should always be evaluated from a perspective of practicality by executive booking personnel.
8

Modélisation et décomposition des problèmes de transbordement dynamiques : application a la répartition des wagons Fret-SNCF

Morin, Marie-Hélène 09 April 1993 (has links) (PDF)
.
9

Modelling and laboratory investigations on freight wagon link suspensions with respect to vehicle-track dynamic interaction

Jönsson, Per-Anders January 2004 (has links)
<p>The link suspension is the most prevailing suspension system for freight wagons in central and western Europe. The system design is simple and has existed for more than 100 years. However, still its characteristics are not fully understood. This thesis emphasizes freight wagon dynamics and comprises three parts:</p><p>In the first part a review of freight wagon running gear is made. The different suspension systems are described and their advantages and disadvantages are discussed. The review covers the running gear standardized by UIC and the conventional so-called three-piece bogie. Additionally five improved three-piece bogies and twelve novel running gear designs are presented.</p><p>The second part focuses on the lateral force-displacement characteristics in the link suspension. Results from stationary measurements on freight wagons and laboratory tests of the link suspension characteristics are presented. To improve understanding of the various mechanisms and phenomena in link suspension systems a simulation model is developed. Link suspension systems have strongly nonlinear characteristics including a hysteresis loop. The loop exhibits usually three characteristic sections with different tangential stiffnesses. The actual contact geometry of the links and end bearings has a significant influence on the characteristics. By wear in ordinary service - as well as by geometric tolerances on new components - the contact geometry may deviate considerably from nominal geometry. Further, it seems that elastic deformation in the contact surfaces has considerable effects on the suspension characteristics, in particular on the initial rolling stiffness for small displacements. Also, flexibilities in links and end bearings influence the characteristics. It is also observed that new components after a short period of dynamic testing can exhibit a very low amount of energy dissipation, a phenomenon that is also indicated in some stationary measurements on wagons.</p><p>To summarize the second part, it appears that the link suspension characteristics are very sensitive to several factors being hard to control in the real world of freight wagon operations. The various stiffnesses and hysteresis loops have a considerable variation and may have a strong influence on the ride qualities of vehicles. As long as the characteristics can not be controlled within closer limits than found in this study, there is a strong need for sensitivity analysis to be made, both in predictive multibody simulations of vehicle dynamics, as well as in verification and acceptance tests.</p><p>In the third part a study on the possibility to improve ride qualities of freight wagons with link suspensions is presented. Parametric studies with multibody dynamic simulations on freight wagons equipped with link-suspension bogies are performed. The effect of supplementary friction and hydraulic damping is investigated under various running conditions: speed, loading, tangent and curved track, wheel-rail contact geometry, track gauge and track irregularities. Substantial improvements of the lateral running behaviour of wagons with link suspension bogies can be achieved - both at ordinary speeds and at increased speeds - by using a proper combination of supplementary hydraulic dampers. Speeds up to 160 km/h could be realistic.</p>
10

Vliv způsobu nakládání krmiva do krmného míchacího vozu na životní prostředí

PULKRAB, Miroslav January 2017 (has links)
This thesis aims to determine the effect of methods of loading feed to the mixer feeder wagon on the environment. Two types of loading devices were chosen for observation in the selected agricultural enterprise. The first part of this thesis deals with machines and equipment for feeding of cattle as well as sources, division and effects of noise. In the second part there is described the methodology of measuring noise, characteristics of observed mixer feeder wagons and graphical representation of measured values. The conclusion of this thesis deals with comparison of the measured values and evaluation of this issue.

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