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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.
51

Stone exposures : a cultural geology of the Jurassic Coast

Ferraby, Rose January 2015 (has links)
People have varied and complex relationships with stone, in its raw geology and in its altered forms. Often, however, in cultural contexts, stone remains in the background, as a taken for granted and unremarkable element of the material world. In this thesis, stone moves into the foreground. The research presented here explores how close attention to those who work intimately with stone can disclose unexpected and absorbing stories. The cultural geologies extracted and presented in this thesis cast light on the diversity of ways in which people relate to, and with, the land; and experiment with a range of different ways in which these relations can be narrated. Set on the Jurassic Coast, in the south west of England, the stone exposures that emerge along the margin between land and sea offer a productive site for developing a cultural geological approach. The limestones, shales and clays are framed, in this work, by the narratives of quarrymen and geologists. The work explores how their particular knowledges are formed, and how they exist within wider historical and ecological understandings. Their narratives bring the stratigraphy to life, and draw attention to the hidden worlds within it. The different priorities and perspectives of quarrymen and geologists are shown to lead in different directions, interweave, or run parallel. The very specific languages and descriptions they employ reveal a level of complexity and richness of detail that is mirrored in the stone. Using an approach that combines close observation and creative practice, this study examines stone at a variety of scales, and in different contexts. The work engages with specific stone types, landscapes, voids, buildings and objects. Processes of working stone through practices of lettering, sculpture and masonry elicit understandings of the material that reach far beneath its surface. The absent spaces of quarries are then explored, showing how voids can be animated with knowledge, and how destructive processes can generate creative potential, when sensitively worked and considered. Lastly, the study draws all these ideas together in a discussion of stone assemblages in buildings, to see how voices from geology and quarrying can foster greater understanding of how buildings were constructed in the past, and how we conserve them into the future.
52

Les meules à grains et les meulières dans le Sud-Est de la France du IVe siècle avant JC au XIIe siècle après JC

Longepierre, Samuel 16 February 2011 (has links)
Grâce à l’étude de nombreuses meules rotatives issues de fouilles archéologiques menées ces dernières années dans le Sud-Est de la France, en Languedoc-Roussillon et en Provence, nous pouvons proposer une classification des grands types de moulins à grains employés dans ces régions entre le IVe siècle avant J.-C. et le XIIe siècle après J.-C. Selon les périodes, l’utilisation des moulins manuels a été prédominante ou, au contraire, marginale. Dans ce second cas, des moulins de grand format à usage collectif les ont remplacés. Certains ont fonctionné dans des installations hydrauliques, les autres, tractés par des hommes ou des bêtes, sont notamment illustrés par les moulins pompéiens fabriqués aux environs d’Orvieto en Italie et amplement distribués en Narbonnaise durant l’Empire. Nous examinons aussi les grandes meulières d’où provient une part importante des meules étudiées. L’une d’elles, la meulière de Saint-Quentin-la-Poterie dans le Gard, a laissé de beaux vestiges révélant une organisation très rationnelle de cette exploitation. Datée de l’Antiquité tardive, elle se place à une époque où les meules en grès et en conglomérat ont succédé à celles en roche volcanique presque exclusives dès le deuxième âge du Fer. / Through the study of many rotary grinders from archaeological excavations conducted in recent years in the South East of France, Languedoc-Roussillon and Provence, we propose a classification of major types of grain mills used in these regions between the fourth century BC and the twelfth century AD. According to the period, the hand mills were used substantially or marginally. In this second case, large mills for common use replaced them. Some functionned in hydraulic systems, others towed by men or beasts, are illustrated by the Pompeian mills built in the vicinity of Orvieto in Italy and widely distributed in Narbonne in the Empire. We also examine great millstone quarries from which a significant part of the millstones studied come from. One of them, the millstone quarry of Saint-Quentin-la-Poterie Gard, has left beautiful traces revealing a very rational organization of quarrying. Dating from late antiquity, it ranks at a time when the wheels of sandstone and conglomerate succeeded to those prevailing in volcanic rock in the second Iron Age.
53

El paisaje natural de las lomas de Cantera (Lima) / The natural landscape of the Cantera hills (Lima)

Sánchez Mascaro, Jahayra de los Angeles 07 July 2021 (has links)
En la actualidad, existen diversas áreas naturales en el Perú, entre ellas encontramos a las lomas costeras. Estos hermosos paisajes se encargan de reverdecer la costa peruana con una infinita riqueza dentro de su ecosistema. Su principal característica es que son estacionales, por ende, la belleza de su paisaje es dependiente del cambio de las estaciones. La siguiente investigación, tiene como objetivo general proponer una colección de moda prêt-à-porter femenina a partir del análisis teórico y visual del paisaje natural de las lomas de Cantera, ubicadas en el distrito de Nuevo Imperial en la provincia de Cañete. Así pues, se centrará en explicar las principales características de este paisaje natural, definir cómo el concepto de preservación de espacios a naturales se vincula con esta colección y describir la situación actual de las lomas de Cantera. Asimismo, para realizar el proceso de diseño se recopilarán las referencias visuales de este paisaje y se documentará el proceso de experimentación visual de color, formas y texturas, a través de moodboards y composiciones con técnica de collage. Por último, se diseñará una colección, partiendo desde los bocetos, hasta llegar a la selección de los diez diseños finales. / At present, there are several natural areas in Peru, among them we find the coastal hills. These beautiful landscapes are responsible for greening the Peruvian coast with an infinite wealth within its ecosystem. Its main characteristic is that they are seasonal, therefore, the beauty of its landscape is dependent on the change of the seasons. The following research has the general objective of proposing a collection of women's ready-to-wear fashion based on the theoretical and visual analysis of the natural landscape of the Cantera hills, located in the Nuevo Imperial district in the province of Cañete. Thus, it will focus on explaining the main characteristics of this natural landscape, defining how the concept of preservation of natural spaces is linked to this collection and describing the current situation of the Cantera hills. Likewise, in order to carry out the design process, the visual references of this landscape will be compiled and the process of visual experimentation with color, shapes and textures will be documented, through moodboards and compositions with the collage technique. Finally, a collection will be designed, starting from the sketches, until reaching the selection of the final ten designs. / Trabajo de investigación
54

Modular Communications Relay for Autonomous Quarry Operation

Knutsson, Simon, Larmark, Daniel January 2018 (has links)
Today’s quarries face a change in the operational processes, where the development of automated transport systems and machines have intensified the necessity for reliable and stable data transfer. Within the dynamic environment, with piles building up suddenly, frequently changing mining faces due to blasting, as well as a frequently changing general environment that affect the network coverage negatively, there is a need for a solution that can adapt to the changing environment. The aim of this research has been to investigate the requirements for a dynamic infrastructure, and develop a platform based on today’s available technical solution components that can act as a dynamic platform for the evolving autonomous quarry. This by also reducing the time the worker is exposed to the harsh environment that the quarry presents. The research was conducted through a combination of a product development strategy and Design Research Methodology to develop a concept that fulfills the customer needs that are identified. An iterative process, where the needs were translated in to prototypes, has created learnings through every step of the development process. The result is a relocatable platform for communications relay, which is mounted on a trailer with a fixed mast to distribute short-wave communications in the area where the mobile unit is needed. The trailer is equipped with a four-point leveling system that also act as a stabilization system for the unit and ensures that the platform maintains a horizontal plane at all times. This platform is a first step towards a fully autonomous management of the communication infrastructure which in the future will be needed when a stable process and connection is necessary in the frequently changing environment. The relocatable platform is a necessity for adaption of the short-wave communication in the constantly changing environment. Since this is a first iteration and concept in the development of a dynamic platform, extensive field tests are required to determine which subcomponents are in need of further development or optimization. The completed prototype for the platform is functional and field ready for further testing in its real environment for further collecting of data points. This concept is a subcomponent of a larger system, where the goal is to increase the productivity and reduce the environmental impact from today’s quarry industry. Through reduction of human interaction and management of the relocation of the mobile unit, the workers safety is increased and the harsh environmental exposure is reduced.
55

Petrology and Geochemistry of the Morrison Formation, Dinosaur Quarry Quadrangle, Utah

Bilbey, Sue Ann 01 May 1973 (has links)
Mineralogical and petrographic analyses of the upper Jurassic - lower Cretaceous units in the vicinity of the Dinosaur National Monument quarry near Jensen, Utah, have elucidated their characteristics and the locations of formational boundaries. The lower part of the Morrison Formation is distinguished by a decreased amount of illite and an increased amount of kaolinite. In contrast, the underlying Curtis Formation contains an approximately equal mixture of illite and kaolinite. The lower Salt Wash Member and the upper Brushy Basin Member of the Morrison are both lithologically and mineralogically identifiable in this area. Above the boundary between the two, kaolinite decreases and illite increases. The strata above the Morrison, here recognized as an extension of the Cedar Mountain Formation, reveal another change in clay content. They contain kaolinite as the dominant clay mineral, whereas illite is almost completely absent. The upper Curtis Formation is a near-shore marine deposit, whereas the members of the Morrison Formation are fluvial and lacustrine. A possible climatic or depositional change is equated with the changes in the clay content within the members of the Morrison Formation. After deposition of the Morrison, the lower Cretaceous sediments that now comprise the Cedar Mountain Formation accumulated. These formed in a transitional zone (fluvial to littoral) and were eventually covered by the Dakota Formation (littoral) and the Mowry Formation (marine).
56

Модернизация механизма открывания днища ковша экскаватора ЭКГ-20, производства ПАО "Уралмашзавод" : магистерская диссертация / Modernization of the mechanism of opening the bottom of the bucket of an excavator EKG-20, produced by PJSC "Uralmashzavod"

Алексеев, И. А., Alekseev, I. A. January 2019 (has links)
Одним из основных видов оборудования для горнодобывающей промышленности является экскаватор. Наиболее крупным производителем данного вида оборудования в Российской федерации является ПАО «Уралмашзавод» г. Екатеринбург. Наиболее распространенным среди используемых экскаваторов является серийный электрический экскаватор ЭКГ-20 с гусеничным ходом и с объемом ковша от 18 до 22 куб.м по международному стандарту SAE J67. На основе собранных статистических данных было проведено исследование эффективности работы экскаватора. Основным критерием, определяющим эффективность экскаватора. В ходе статистического исследования было выявлено, что наибольший процент аварийных простоев, связан с механизмом открывания днища ковша. Объектом данного проекта является электрический одноковшовый карьерный экскаватор ЭКГ-20, производства ПАО «Уралмашзавод». Предметом исследования является механизма открывания днища ковша. Основная цель данной работы является модернизация механизм открывания днища ковша, а также проведение анализа эксплуатационных показателей и экономической целесообразности проведения модернизации. / One of the main types of equipment for the mining industry is an excavator. PJSC "Uralmashzavod". Yekaterinburg. The most common among the types of excavators is a serial electric excavator EKG-20 with a delivery capacity of 18 to 22 cubic meters according to the international standard SAE J67. Based on the collected statistical data, a study was conducted of the efficiency of the excavator. The main criterion for determining the effectiveness of an excavator. In the course of statistical studies, it was found that the largest percentage of emergency downtime is associated with the opening mechanism of the bottom of the bucket. The object of this project is an electric single-bucket mining excavator EKG-20, produced by PJSC "Uralmashzavod". The subject of research is the mechanism of opening the bottom of the bucket. The main goal of this work is to modernize the mechanism for opening carpet days, as well as to analyze the performance indicators and the economic feasibility of modernization.
57

Shipyard to Stoneyard: The Capitol Stones at the Intersection of Material and Memory

Ashcraft, Andrew Eric 03 July 2023 (has links)
The Capitol Stones in Washington DC's Rock Creek Park were a delight for urban explorers, a curiosity for historians, and a tangible connection for descendants of enslaved laborers who quarried, transported, and shaped them into the United States Capitol. Banished from the East Front of the Capitol in 1958, they have spent the last third of their existence "not quite dumped, but not quite preserved either" (Banville 2009). To the National Park Service, they are a liability; to the Architect of the Capitol, a resource. At the time of writing, the stones are being relocated to a secure government storage facility where they will be permanently locked away from public view. This thesis proposes an alternative: relocate the Capitol Stones to an adaptively reused factory at the Navy Yard, where they can be stored, visited, and studied in a cavernous daylit atrium. In addition to housing the stones, as part of this thesis the WWII era naval weapons factory features retail at ground level and residences on four stories above. To the north, the atrium recalls the park-like setting of the stones' recent past, while the southern end is a working space for masons training to preserve historic buildings constructed of the same Aquia Creek sandstone. Due to the Anacostia's shifting shoreline, the site of Building 202 is also a likely location of the wharf at which the Capitol Stones first arrived in the District after being floated upriver from their Stafford County quarry. This crucial moment is marked by a contemplative memorial which stands in memory of the enslaved laborers who, across various levels of skill, built the Capitol. On axis with the memorial, the Capitol's East Portico - the origin of the Capitol Stones - is remembered at full scale. / Master of Architecture / Seemingly abandoned behind a maintenance shed in Washington DC's Rock Creek Park was a large collection of intricately hand carved stones. Urban explorers, historians, and descendants of enslaved laborers knew them as the Capitol Stones, which formed the East Front of the United States Capitol from the 1820s to the 1950s. But much like they were evicted from the Capitol, the Stones are presently facing eviction from Rock Creek Park. At the time of writing, the stones are being relocated to a secure government storage facility where they will be permanently locked away from public view. But what if they could remain accessible? This thesis proposes the relocation of the Capitol Stones into the light-filled atrium of a WWII era naval weapons factory, formerly part of the Washington Navy Yard. The atrium is enveloped by retail and residential space, as well as a training center for apprentice masons learning to use the Capitol Stones as a quarry. Stripped of their original purpose, the Capitol Stones have found new value as replacement stones at the other historic buildings. The factory, Building 202, occupies dredged and filled land which at the time of the Capitol's construction was part of the Anacostia River and the likely site of Commissioner's Wharf, the pier at which the Capitol Stones were delivered from the Aquia Creek Quarry in Stafford County, VA. Recalling this pivotal occasion, the stones surround a contemplative memorial to enslaved laborers who built the Capitol. To the east of the memorial stands a life sized representation of the East Front of the Capitol, the origin of the Capitol Stones.
58

Evaluation of Particulate Matter Inside Control Rooms at a Quarry and Processing Facility

Backes, Audrey Ann January 2014 (has links)
No description available.
59

Designing Simulation Model for Open-Pit Mining Charging Infrastructure

Fredin, Alex, Pogén, Mattias January 2024 (has links)
The emission-heavy open-pit mining industry is exploring a new emission-free era with electrified autonomous haulers. The new technology has challenges, such as designing charging infrastructure for complex environments. This thesis addresses these challenges with a simulation model. This thesis aims to create a foundation and enhance decision-making for designing and evaluating charging infrastructure for Volvo Autonomous Solutions. The paper investigates various charging infrastructure designs using a simulation model verified by Volvo Autonomous Solutions employees, prioritizing minimizing the total cost of ownership and simultaneously meeting the production goal. The project consists of phases such as Needfinding and Research, Modeling, Simulation, and Validation, each aligned with specific activities inspired by Design Thinking principles. The simulation model is developed iterative with a specific site as the case. Several meetings were conducted with the co-advisor and supervisor to validate the simulation model. The thesis has developed a simulation model for charging infrastructures specifically designed for open-pit quarries. The simulation model was developed to make changes to the system easily. Adaptiveness is needed for the constantly changing environment or testing a new open-pit quarry. How to design charging infrastructure for open-pit quarries was found to be a research gap, and there is also an industrial need for guidance on how it should be designed. The scientific contribution concludes that important factors are important in designing charging infrastructure. Whereas the industrial contribution concludes, the simulation model is configured. / Den utsläppstunga dagbrottsindustrin utforskar en ny utsläppsfri era med elektrifierade autonoma dumprar. Den nya tekniken har utmaningar, som att designa laddinfrastruktur för komplexa miljöer. Denna avhandling tar uppdessa utmaningar med en simuleringsmodell. Examensarbetet syftar till att skapa en grund och förbättra beslutsfattandet för design och utvärdering av laddinfrastruktur för Volvo Autonomous Solutions. Uppsatsen undersöker olika designer av laddinfrastruktur med hjälp av en simuleringsmodell som verifierats av anställda på Volvo Autonomous Solutions, med prioritet att minimera den totala ägandekostnaden och samtidigt uppfylla produktionsmålet. Projektet bestod av faser som Needfinding och Research, Modellering, Simulering och Validering, var och en anpassad till specifika aktiviteter inspirerade av Design Thinking principer. Simuleringsmodellen utvecklades iterativt med ett specifik dagbrott som fall. Flera möten genomfördes med företagshandledare och handledare för att validera simuleringsmodellen. Avhandlingen har utvecklat en simuleringsmodell för laddningsinfrastruktur speciellt utformad för dagbrott. Simuleringsmodellen utvecklades för att enkelt kunna göra ändringar i systemet. Anpassningsförmåga behövs för den ständigt föränderliga miljön eller för att testa ett nytt dagbrott. Hur man utformar laddinfrastruktur för dagbrott visade sig vara ett forskningsgap och det finns också ett industriellt behov av vägledning om hur den ska utformas. Det vetenskapliga bidraget drar slutsatser om viktiga faktorer vid utformningen av laddinfrastruktur. Medan det industriella bidraget drar slutsatser om konfigurationen av simuleringsmodellen.
60

Integrated quarry rehabilitation strategy for sustainable renaturation in Lebanon

Yacoub, Adel Joseph 23 January 2012 (has links)
In der Geschichte Libanons sind Steinbrüche immer für die Gewinnung von Baumaterialien wie Sand, Kies, Steine, Zement usw. genutzt worden. Durch die Komplexität dieses Sektors im Libanon gibt es kaum verfügbare Daten, Erhebungen und Studien über Ausmaß und Auswirkungen der Abbautätigkeit. Deshalb behandelt die vorliegende Untersuchung eines der drängendsten Probleme und legt eine aktuelle Datenübersicht über die Steinbrüche vor. Es ist ein vollständiger und integrierter Überblick über die Steinbrüche im Libanon im Allgemeinen und das Problem ihre Rehabilitation im Besonderen unter Berücksichtigung des schwierigen Themas eines integrierten Steinbruchmanagements in einem nachhaltigen Konzept. Meilensteine und Etappen bei der Etablierung eines Rehabilitationsprogrammes werden auf unterschiedlichen Ebenen wie der öffentliche Sektor, der private Sektor und den öffentlichen Kommunen entwickelt. Um die Nachhaltigkeit des Rehabilitationskonzeptes aufzuzeigen, wurde ein Feldexperiment in einem ehemaligen Steinbruch nördlich von Beirut angelegt. Bei dieser Rehabilitation wurden in die aufgebrachte Bodenschicht Johannisbrotbäume (Ceratonia siliqua) aufgepflanzt. Durch diese Fallstudie konnte die Nachhaltigkeit der Maßnahme für das Management natürlicher Ressourcen geprüft, unterschiedliche Ergebnisse validiert und untersucht werden. / Throughout Lebanon’s history, quarries have been used as a means to extract essential construction materials such as sand, aggregates, stone masonry, cement, block stone, and others. Due to complexity of the quarry sector in Lebanon very few data are available, records and studies in this field are limited. Therefore, the presented research tackles one of Lebanon’s most pressing issues and represents the most updated database on quarries in Lebanon. A comprehensive and integrated overview of the quarries issue in Lebanon in general and the problem of rehabilitation in particular are given and the problematical topic of an integrated quarry planning within a sustainable development concept in Lebanon is pointed out. Milestones and landmarks toward the adoption of a setup needed for the proper rehabilitation approach at different levels as public sector, private sector and local communities are developed. In order to demonstrate the rehabilitation concept was realised a field experiment in a closed quarry northerly from Beirut. The rehabilitation was finalised by planting of carob trees (Ceratonia siliqua) in a layer of top soil. By this case study it was possible to address a sustainable procedure for natural resources management, examine and validate.

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