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Hameury, Stéphane. "Heat and moisture buffering capacity of heavy timber constructions /." Stockholm, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-383.
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Gredin, Anders, and Martin Freiling. "Sunda energieffektiva väggkonstruktioner för morgondagens flerbostadshus." Thesis, KTH, Byggteknik och design, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-102117.
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Detta examensarbete har utförts vid högskoleingenjörsprogrammet Byggteknik och design vid Kungliga Tekniska högskolan och i samarbete med Ramböll Sverige. Syftet med denna rapport är att undersöka och analysera dagens ytterväggskonstruktioner för framtidens energieffektiva flerbostadshus. Ytterväggskonstruktionen som är en del i byggnadens klimatskal, har en viktig och betydelsefull funktion för att kunna klara av framtida byggnaders energikrav. För att en väggkonstruktion ska fungera finns det en rad andra påverkande faktorer som måste tas hänsyn till. Därför kommer examensarbetet att fokusera på ytterväggskonstruktioners byggfysikaliska egenskaper såsom lufttäthet, fukt, uppbyggnad och beständighet. För att kunna lösa uppgiften har vi varit i kontakt med åtta olika byggnadsentreprenörer i Stockholmsområdet och utfört studiebesök ute i produktionen. Det finns flera faktorer som styr valet av ytterväggskonstruktion för projektet och på grund av detta finns det en rad olika typer av ytterväggskonstruktioner som används i dagens byggande av flerbostadshus. I vår jämförelse mellan sex olika ytterväggskonstruktioner har vi analyserat byggfysikaliska egenskaper och produktionsmetoder utifrån samma grundparametrar. Eftersom ytterväggarna skiljer sig mellan lätt respektive tung stomme har vi valt att presentera en från varje kategori. Enligt vår bedömning i vår analys har vi kommit fram till att en lätt utfackningsvägg med stålregelstomme och en tung väggkonstruktion med platsgjuten skalväggsstomme har de bästa förutsättningarna för att i framtiden utgöra de främsta alternativen inom ytterväggskonstruktioner för flerbostadshus.Rapporten är skriven för läsare som antas ha viss kunskap inom området byggteknik, dvs. den riktar sig främst till intressenter till byggbranschen och studenter inom området.This thesis has been carried out at the Bachelor's program of construction engineering and design at the Royal Institute of Technology and in collaboration with Ramböll Sweden. The purpose of this report is to examine and analyze today's outer wall structures for the future of energy efficient buildings. The outer wall construction that is part of the building envelope has an important and significant flaw to meet future energy requirements of buildings. For a long time different wall construction projects have been designed to create wall panels with low U-values. For a wall structure to function, there are a number of confounding factors to be taken into account. Therefore, the thesis will focus on outer wall structure building physical properties such as air density, moisture, structure and stability. In order to solve the task we have been in contact with eight different contractors in the Stockholm area and conducted field trips out in production. There are several factors that determine the choice of exterior wall construction for the project and because of this there are a number of different types of exterior wall structures used in today's construction of apartment buildings. In our comparison of six different wall constructions, we have analyzed the construction of physical characteristics and production methods on the same basic parameters. Since the outer walls differ between light and heavy body, we have chosen to present one from each class. Our conclusion is that a light stud walls with steel stud frame and a heavy wall construction with in-situ shell wall structure is best equipped to continue being the main option in exterior wall construction for apartment buildings. The report is written for readers who knowledgeable in the field of building technology, i.e. it is mainly addressed to interested parties in the construction industry and students in the field.
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Kristjánsdóttir, Rut. "Design of Heavy DutyPavements." Thesis, KTH, Byggnadsmaterial, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-218502.
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This research is focused on design of Heavy Duty Pavement which is when a pavement loading exceeds highway levels. The environment where these conditions occur are for example at ports, industrial areas and airport because of the use of heavy vehicles as handling of containers by Straddle Carriers, Front Lift Trucks or Reach Stackers, airplanes and more. The main emphasis here will be on heavy duty pavements for ports. Different design methods are discussed and compared for the pavement design of ports. In this research two different design methods are thoroughly analyzed, the British Ports Associations Heavy Duty Pavements Manual which is a chart based procedure and the HIPAVE program which is an Australian Heavy Duty Pavement Design Guide. Both those methods are widely used around the world. Furthermore, an analysis is performed to research the plastic properties of the pavement. In most design methods, the material properties of the granular materials are assumed as elastic when they are not, they are elasto-plastic. A Finite Element Analysis is performed to determine if this assumption has significant effect on the design of pavements by comparing models of a design pavement section with elastic granular materials and elasto-plastic granular materials. The main conclusions from the comparison study of different pavement design methods are when using the HIPAVE program the total thickness of the design pavement section is smaller than using the British Ports Manual. Smaller thickness result in less materials needed for and therefor lower cost for the pavement section. Regarding the plasticity analysis, it is concluded that the assumption to model the behavior of unbound granular materials as elastic in pavement design is correct. The Finite Element Analysis determined that plasticity does have effect on the behavior of the materials with respect to elastic behavior, but there is not a considerable difference in pavement displacement between the two analysis.
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Berli, Markus. "Compaction of agricultural subsoils by tracked heavy construction machinery /." Zürich, 2001. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=14132.
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Blaxton, Allen C., Michael J. Fay, Cheryl M. Hansen, Christopher M. Zuchristian, Allen C. Blaxton, Michael J. Fay, and Cheryl M. Hansen. "An analysis of USMC heavy construction equipment (HCE) requirements." Monterey, California. Naval Postgraduate School, 2003. http://hdl.handle.net/10945/9854.
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MBA Professional ReportApproved for public release; distribution is unlimited.
MBA Professional Report
Approved for public release; distribution is unlimited.
According to I and L, HQMC, the Marine Corps needs to re-evaluate current operational requirements for engineer construction equipment. Acquisition and force allocation levels for equipment have remained essentially at constant 1970's, Cold War levels. Because acquisition and allocation levels haven't changed at the same rate as personnel, there is a perception that much of the existing equipment is unnecessary. Impacts for supporting too much equipment are decreased readiness, increased maintenance requirements, and increased O and M costs. The objective of our MBA project is to identify the correct quantity of construction equipment required to support the future needs of the USMC, focusing on unit training and Marine Expeditionary Unit (MEU) deployment cycles. This study will also evaluate the cost effectiveness of various alternatives for supplying the right amount and mix of CE to support contingencies via the civilian industrial base (lease/purchase decision factors, as well as domestic/international supplier issues). Our group will perform a review of USMC CE acquisition history to determine how the Marines have procured engineer equipment. Additionally, we will determine the annual volume of equipment that has been purchased or otherwise procured from industrial sources and the expected life cycle of existing equipment owned by the Marine Corps. With this information, we will assess the ability and willingness of suppliers worldwide to provide needed equipment for replacement of expired gear or in support of emergent contingencies. Our objectives are to determine the correct amount and mix of construction equipment to maintain at the Battalion level and to identify some cost effective alternatives for supporting battalion operations and training requirements.
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Blaxton, Allen C. Fay Michael J. Hansen Cheryl M. Zuchristian Christopher M. "An analysis of USMC heavy construction equipment (HCE) requirements /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Jun%5FBlaxton.pdf.
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Thesis (M.B.A.)--Naval Postgraduate School, June 2003.Thesis advisor(s): Donald R. Eaton, Joe G. San Miguel, Raymond E. Franck, Keebom Kang. "MBA professional report." Joint authors: Michael J. Fay, Cheryl M. Hansen, Christopher M. Zuchristian. Includes bibliographical references (p. 129-130). Also available online.
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Cook, Rickey A. "A crane and heavy equipment maintenance plan for improving safety and efficiencey." Online version, 1999. http://www.uwstout.edu/lib/thesis/1999/1999cook.pdf.
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Sepehri, Nariman. "Dynamic simulation and control of teleoperated heavy-duty hydraulic manipulators." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30846.
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Some relevant aspects of dynamics and control of heavy-duty hydraulic machines in a teleoperated mode were investigated. These machines, such as excavators and forest
harvesters, are mostly used in primary industries. They have a manipulator-like structure with a nonlinear and coupled actuating system. The aim of the project is to investigate different approaches towards converting such machines, with minimum changes, into task-oriented human-supervisory control systems. This provides the opportunity
to use both human supervision and robotic power in hazardous environments and for tasks for which human decision is necessary.
A methodology was developed for fast and accurate simulations. Analytical, steady-state and numerical techniques were combined using Large-Scale Systems analysis. The inclusion of nonlinearities in the form of discontinuities (e.g., gear backlash and stick-slip friction) in the model was investigated. Numerical simplifications of the structural dynamics and alternative solutions for the hydraulic part were also studied.
The model describing the performance of the machine has been written in ACSL (Advanced Continuous Simulation Language) on a VAX computer system. A modified version of the program is at present running close to real-time on a single processor in conjunction with high speed graphics in a manner similar to a flight simulator used for human interface studies and training.
The model also evaluates the performance of the machine in a teleoperated mode and under different control strategies. As a result a velocity control algorithm has been developed which is applied in conjunction with the closed-loop components for teleoperation of heavy-duty hydraulic machines; it is basically a feedforward compensation
which uses the measured hydraulic line pressures along with fluid-flow equations as criteria
to control the joint velocities as well as to uncouple the interconnected actuating system. The control algorithm has been written in C language and is running on an IRONICS computer system, interfaced between the human operator and the machine. The simulation results are supported by the experimental evidence. The experiments were performed on a Caterpillar 215B excavator.
Improved operator safety, extension of human capability, job quality and productivity
increase are the advantages of a successful implementation of robotic technology to these industrial machines.Applied Science, Faculty of
Mechanical Engineering, Department of
Graduate
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Ghorbanian, Kerdabadi Mohammad Reza. "Seamus Heany et la (dé)construction du sujet." Caen, 2007. http://www.theses.fr/2007CAEN1477.
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L'œuvre de Seamus Heaney est marquée par l'existence d'un sujet pluriel, qui a été négligée en raison de l'intérêt privilégié des critiques pour des facteurs extérieurs au texte. Bien que les lectures de son œuvre soient donc influencées par les troubles de l'Irlande du Nord, la présente étude essaie d'examiner le processus de développement du sujet lyrique créé dans la poésie de Heaney indépendamment de l'influence de ces troubles. Les principes poétiques de la subjectivité, implicitement abordés dans la prose de Heaney, constituent la source principale de l'analyse du sujet. Pour compléter les conceptions du poète, l’étude utilise les théories de la subjectivite présentées par Nietzsche, Jung, Rorty et Kristeva. La majeure partie de l'œuvre de Heaney, aussi bien prose que poésie, jusqu'en 2002, date de parution d'Electric Light, est donc abordée dans le but d'élucider le processus de la subjectivisation. Pour définir les problématiques de la subjectivité et du sujet lyrique, la recherche se concentre sur la subjectivité dans le texte de Heaney. L'analyse de cette œuvre révèle que les poèmes constituent des fragments d'une mosaïque qui dépeint le développement d'un "sujet en procès", un artiste en quête de la création du soi comme dans un Künstlerroman. Ainsi, loin d'être un sujet soumis à l'idéologie, c’est un artiste non-conformiste qui évolue selon différentes étapes distinctes, marquées par l'exploration, la dissociation d’avec le groupe, et la révolte. Ce qui caractérise ce sujet est sa résistance face à un espace menaçant qui essaie de le conditionner à sa façon, à l’opposé de ses propres principes artistiques. En choisissant la nature de sa relation avec la société, avec l'altérité et avec le langage, il accomplit son objectif. Il parvient à créer son soi par sa révolution dans la société, dans le temps et dans le langage poétique. Cette dernière étape aboutit à l'individuation poétique qui, à son tour, a comme conséquence le renouveau du sujet et la genèse d'une nouvelle vision
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Dalton, Susan Iris. "Social norms associated with drinking : their nature and influence upon untreated heavy drinking." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369375.
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Zimmerman, Nathan. "Vanadium Redox Flow Battery : Sizing of VRB in electrified heavy construction equipment." Thesis, Mälardalens högskola, Framtidens energi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-26918.
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In an effort to reduce global emissions by electrifying vehicles and machines with internal combustion engines has led to the development of batteries that are more powerful and efficient than the common lead acid battery. One of the most popular batteries being used for such an installation is lithium ion, but due to its short effective usable lifetime, charging time, and costs has driven researcher to other technologies to replace it. Vanadium redox flow batteries have come into the spotlight recently as a means of replacing rechargeable batteries in electric vehicles and has previously be used mainly to store energy for load leveling. It possesses many qualities that would be beneficial to electrify vehicles. The battery has the ability for power and energy to be sized independently which is not dissimilar to internal combustion vehicles. It also has the potential for a tolerance to low discharges, fast response time, and can quickly be refueled by replacing the electrolyte; just like is done when a car refuels at the gas station. The purpose of the study is to determine the possibility of using vanadium redox flow batteries to power heavy construction equipment, a wheel loader, with a finite amount of space available for implementation. A model has been designed in MATLAB to determine how long the battery could last under typically applications for the wheel loader which needs a peak power of 200 kW. From the volume available it has been determined that the battery can be installed with an energy capacity of 148 kWh. The results of the model show that vanadium redox flow batteries can be used to power a wheel loader but due to the limiting energy density and cell components it remains to be impractical.
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Lage, Raquel Rodrigues. "A construção pesada brasileira." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/8/8136/tde-26042018-122429/.
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A construção pesada brasileira, setor produtor das rodovias, túneis, aeroportos, portos, ferrovias, metrovias, barragens, usinas hidrelétricas e obras de arte, pontes e viadutos - bens que compõem a infraestrutura nacional - além de dinamizar diretamente as demais indústrias, contribuir para ocupação da mão de obra e absorver conhecimento tecnológico, é também formadora de uma engenharia nacional de alta especialidade técnica, reconhecida e respeitada no mundo todo. Para se entender a pujança desta atividade industrial, parte-se da gênese histórica da construção pesada nacional e das grandes firmas. Verifica-se o funcionamento do setor, aspectos técnicos, jurídicos, econômicos, políticas, materiais, máquinas, pessoal e demanda. E, por fim, a distribuição espacial, localização de obras e empresas. A estruturação da construção pesada acompanha o processo da industrialização nacional, dinamizado, sobretudo, a partir dos anos 1930. De 1960 a 1970 o setor montado vive a expansão interna com o aumento da demanda e início da inserção no mercado regional. Após a desaceleração da demanda interna a partir dos anos 1980, as construtoras partem para concessões de serviços públicos e demanda externa de construção de obras pesadas. Mantém-se pela expansão via diversificação de atuação e multinacionalização, as quais tomam força a partir da década 1990. Com as políticas nacionais de privatizações passam a atuar as firmas em saneamento, telecomunicações, energia, petroquímicos, transportes, defesa, mineração, óleo e gás, bioenergia, mobilidade urbana, empreendimentos imobiliários, têxtil, naval. Nos anos 2000 consolidam-se como grandes grupos empresariais atuantes nos mais diversos setores econômicos e retomam com força às atividades de construção de infraestruturas internas estimuladas por novas demandas públicas. A partir dos anos 2010 inicia-se o reajuste do setor. O objetivo principal deste trabalho é o de compreender o setor da construção pesada brasileira sua consolidação, expansão e multinacionalização, a partir da combinação de aspectos naturais e sociais. Um setor complexo que atingiu preponderância regional e consagrado destaque mundial associado ao protagonismo de empresas, que começaram pequenas, cresceram, disputaram e ganharam mercados internacionais, demonstrando excelência.Brazilian heavy construction, road, highways, railroads, underground, marine construction, bridges, tunnels, harbor and port facilities construction, dams, hydroelectric power plant construction infrastructure suppliers products - besides being important to the overall economy, pushing other industries, it contributes to job generation and technological knowledge, and it is also responsible for a high specialized national engineering, acknowledged and respect all over the world. To understand the strength of this sector, firstly the research follows historical data about beginning of Brazilian heavy construction industry and Brazilian main enterprises. Then how the sector works, technical activities, rules, laws and regulations, policies and practices, materials, equipments, labor and demand. Finally where main heavy constructions have been distributed and Brazilian contractors are located. Brazilian heavy construction sector increased while the national industrialization process was set down planning by political policies most since 1930. From 1960 to 1970 stimulated by public sector and assistance from the federal government and domestic demand Brazilian contractors reach technical skills make them ready to foreign market. When recession issues from the 1980s weaken some Brazilian industries, contractors start operating new segments as public service concessions merging more easily export policies. Consolidated in the 1990s whether by diversification due to privatization projects or multinationalization strategies. They have started business in sanitation, telecommunication, power, petrochemicals, transportation, defense, mining, oil and gas, bioenergy, building construction. In the 2000 already powerful organized corporations acting in many different economic activities, attracted by internal infrastructure demand, they come back where they had started. From 2010 sector has known little by little its breakdown. This text intends to understand Brazilian heavy construction its beginning, consolidations, development, distribution and internationalization, following natural and social aspects arrangement. A very complex sector which had a long time achieved regional leadership and worldwide acknowledgment.
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Evans, Thomas H. "Design of composite sandwich panels for lightweight applications in heavy vehicle systems." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4745.
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Thesis (M.S.)--West Virginia University, 2006.Title from document title page. Document formatted into pages; contains ix, 125 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 124-125).
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Lima, Pedro. "Predictive control for autonomous driving : With experimental evaluation on a heavy-duty construction truck." Licentiate thesis, KTH, Reglerteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-186123.
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Autonomous vehicles is a rapidly expanding field, and promise to play an important role in society. In more isolated environments, vehicle automation can bring significant efficiency and production benefits and it eliminates repetitive jobs that can lead to inattention and accidents. The thesis addresses the problem of lateral and longitudinal dynamics control of autonomous ground vehicles with the purpose of accurate and smooth path following. Clothoids are used in the design of optimal predictive controllers aimed at minimizing the lateral forces and jerks in the vehicle. First, a clothoid-based path sparsification algorithm is proposed to efficiently describe the reference path. This approach relies on a sparseness regularization technique such that a minimal number of clothoids is used to describe the reference path. Second, a clothoid-based model predictive controller (MPCC) is proposed. This controller aims at producing a smooth driving by taking advantage of the clothoid properties. Third, we formulate the problem as an economic model predictive controller (EMPC). In EMPC the objective function contains an economic cost (here represented by comfort or smoothness), which is described by the second and first derivatives of the curvature. Fourth, the generation of feasible speed profiles, and the longitudinal vehicle control for following these, is studied. The speed profile generation is formulated as an optimization problem with two contradictory objectives: to drive as fast as possible while accelerating as little as possible. The longitudinal controller is formulated in a similar way, but in a receding horizon fashion. The experimental evaluation with the EMPC demonstrates its good performance, since the deviation from the path never exceeds 30 cm and in average is 6 cm. In simulation, the EMPC and the MPCC are compared with a pure-pursuit controller (PPC) and a standard MPC. The EMPC clearly outperforms the PPC in terms of path accuracy and the standard MPC in terms of driving smoothness.QC 20160503
iQMatic
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Rohrbaugh, Jeremiah C. "Characterization of infield duty cycles and exhaust emissions from diesel powered off-road heavy duty equipment." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2730.
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Thesis (M.S.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains xx, 174 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 171-172).
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Damasceno, Juliana Lucena Barros. "Requisitos de sustentabilidade aplicáveis ao setor da construção civil pesada." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3146/tde-24082016-085010/.
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A Incorporação da sustentabilidade nas empresas é de fundamental importância para alcançar o desenvolvimento sustentável. Dentro deste contexto, o setor da construção civil pesada tem um papel relevante tanto economicamente, quanto em relação a magnitude dos impactos ambientais e sociais causados pelas suas grandes obras. Este trabalho tem como objetivo identificar os requisitos de sustentabilidade que são aplicáveis às construtoras do setor de construção civil pesada e classificá-los segundo seu grau de importância. Os requisitos foram identificados a partir dos requisitos e diretrizes de sustentabilidade: GRI, ISO 26000, ISO 14001; OHSAS 18001; NBR 16001, SA 8000, ISE e Indicadores Ethos. Os requisitos mapeados foram validados e avaliados quanto ao grau de importância, classificados em sua grande maioria como requisitos importantes e muito importantes. Esta validação ocorreu a partir de um estudo de caso realizado junto as construtoras líderes do setor. O presente trabalho também permitiu identificar algumas iniciativas apresentadas pelas empresas para atender aos requisitos de sustentabilidade.The incorporation of sustainability in business is crucial to achieve sustainable development. Within this context, the heavy construction industry has a role with regard to their economic importance and magnitude of environmental and social impacts caused by its large projects. This research aims to define the sustainability requirements that are applicable to construction companies from the heavy construction industry and classify them according to their degree of importance. The requirements were identified from the requirements and guidelines of sustainability, such as GRI, ISO 26000, ISO 14001, OHSAS 18001, NBR 16001, SA 8000, ISE and Ethos. The requirements mapped were validated and its degree of importance evaluated, classified mostly as important and very important requirements. This validation occurred from a case study conducted with industry-leading construction companies. This study also identified initiatives of the companies to meet the sustainability requirements.
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Manuel, Jack Elliot. "Design, Construction, and Application of an Electrostatic Quadrupole Doublet for Heavy Ion Nuclear Microprobe Research." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1062819/.
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A nuclear microprobe, typically consisting of 2 - 4 quadrupole magnetic lenses and apertures serving as objective and a collimating divergence slits, focuses MeV ions to approximately 1 x 1 μm for modification and analysis of materials. Although far less utilized, electrostatic quadrupole fields similarly afford strong focusing of ions and have the added benefit of doing so independent of ion mass. Instead, electrostatic quadrupole focusing exhibits energy dependence on focusing ions. A heavy ion microprobe could extend the spatial resolution of conventional microprobe techniques to masses untenable by quadrupole magnetic fields. An electrostatic quadrupole doublet focusing system has been designed and constructed using several non-conventional methods and materials for a wide range of microprobe applications. The system was modeled using the software package "Propagate Rays and Aberrations by Matrices" which quantifies system specific parameters such as demagnification and intrinsic aberrations. Direct experimental verification was obtained for several of the parameters associated with the system. Details of the project and with specific applications of the system are presented.
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Klopper, Marthinus Ferreira. "The life expectancy of heavy earthmoving equipment on a sand dune mine in a highly corrosive environment." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/80762.
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Thesis (MBA)--Stellenbosch University, 2004.ENGLISH ABSTRACT: Richards Bay Minerals (RBM) went through a restructuring process in 2002. The effect that these changes had on the life expectancy of the heavy earthmoving equipment (HEME) at the company’s sand dune mining operation situated at Richard’s Bay on the north coast of KwaZulu-Natal, was unknown. This study explores these, and various other factors, that influence the life expectancy of the HEME in this highly corrosive environment. During the last number of years there has been no equipment replacement philosophy at RBM and this has resulted in the average age of HEME at the mine being extremely high. This study suggests that when restructuring is implemented in the wrong way, the process can have significant negative implications. The study determines how the behaviour of especially drivers and maintenance personnel (maintainers) impacts on the expected life of the HEME at RBM. The hidden cost element of driver and maintainer unhappiness, however, is not included as part of this study. In the first part of this study project, the writer focuses on what may have caused the unhappiness, and makes suggestions for further studies aimed at addressing this unhappiness and changing the behaviour of drivers and maintainers. These suggestions should be seen as guidelines, as measures that work in one company may not necessarily work in another. The second part of the study project deals with the replacement philosophy regarding HEME at RBM. The mine has various types of equipment, but the main focus of this research falls on the following: Caterpillar 966- 980 (payloaders), track type equipment Caterpillar D7R/H (dozers), Caterpillar 988- 992 (heavy duty payloaders) and Bell B25 articulated dumptrucks (dumptrucks) Four different replacement models are investigated and discussed in detail. The model that was best aligned with the Caterpillar proposed best replacement practice, as stipulated by the Caterpillar replacement expert, is identified. Finally, a replacement cycle for the different types of equipment is proposed.
AFRIKAANSE OPSOMMING: Richardsbaai Minerale (RBM) het in 2002 deur ‘n herstruktureringsprogram gegaan. Die uitwerking wat die gevolge daarvan op die swaar grondverskuiwingsvoertuie (SGV) gehad het was onbekend. Gedurende die laaste aantal jare was daar geen vervangingsbeleid by RBM nie, en dit het meegebring dat die gemiddelde ouderdom van die SGV op die myn buitengewoon hoog is. Dit is belangrik om te bepaal wat die invloed van menslike gedrag van veral die drywers en herstelpersoneel op die verwagte leeftyd van SGV is. Die versteekte koste wat verbind word met ongelukkige drywers en herstelpersoneel maak nie deel uit van hierdie studie nie. As herstrukturering op die verkeerde manier toegepas word kan dit ‘n negatiewe impak hê. In die studie sal daar aandag gegee word aan wat die negatiewe elemente is en wat is die moontlike oorsaak daarvan. Daar word ook sekere voorstelle gemaak vir toekomstige studies om die ongelukkigheid aan te spreek en ‘n gedragsverandering na vore te bring. Die voorstelle is slegs riglyne en, wat in een maatskappy werk sal nie noodwendig in ‘n ander een werk nie. Die tweede deel van die werkstuk fokus op vervangingsteorieë met betrekking tot die SGV op RBM. Die myn het verskeie tipes SGVs maar die fokus het geval op vier soorte SGV. Hulle is Caterpillar 966- Caterpillar 980 (gemiddelde laaiers), spoor tipe toerusting Caterpillar D7R/H (stootskrapers), Caterpillar 988- Caterpillar 992 (swaargewig mobiele laaiers) en Bell B25 geartikuleerde stortings trokke (stortings trokke). Vier verskillende modelle is ondersoek en deeglik bespreek. Die model met die beste uitslae wat die mas opgekom het ten opsigte van die Caterpillar se voorgestelde beste vervangings praktyk, soos aangedui deur die Caterpillar voertuig vervangings kenner, is ge-identifiseer. Laastens word die vervangingsiklus vir die verskillende tipes toerusting voorgestel.
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Lucko, Gunnar. "A Statistical Analysis and Model of the Residual Value of Different Types of Heavy Construction Equipment." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/11067.
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Residual value is defined as the price for which a used piece of equipment can be sold in the market at a particular time. It is an important element of the owning costs of equipment and needs to be estimated by equipment managers for making investment decisions.
The purpose of this study is to gain insights into the residual value of selected groups of heavy construction equipment and to develop a mathematical model for its prediction. Auction sales data were collected from two online databases. Manufacturer publications and an online source provided size parameters and manufacturers suggested retail prices matching the auction records. Macroeconomic indicator values were collected from a variety of sources, including government agencies. The data were brought into the same electronic format and were matched by model name and calendar date, respectively.
Data from auctions in the U.S. and in Canada were considered for this study. Equipment from four principal manufacturers of up to 15 years of age at the time of sale was included. A total of 35,542 entries were grouped into 11 different equipment types and 28 categories by size as measured by horse power, standard operating weight, or bucket volume. Equipment types considered were track and wheel excavators, wheel and track loaders, backhoe loaders, integrated toolcarriers, rigid frame and articulated trucks, track dozers, motor graders, and wheel tractor scrapers.
Multiple linear regression analyses of the 28 datasets were carried out after outliers had been deleted. Explanatory variables for the regression model were age in years, the indicator variables manufacturer, condition rating, and geographic region, and selected macroeconomic indicators. The response variable was residual value percent, defined as auction price divided by manufacturers suggested retail price. Different first, second, and third-order polynomial models and exponential and logarithmic models of age were examined. A second-order polynomial was selected from these functional forms based on the adjusted coefficient of determination. Coefficients for the 28 models and related statistics were tabulated. A spreadsheet tool incorporating the final regression model and its coefficients was developed. It allows performing the residual value prediction in an interactive and intuitive manner.Ph. D.
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Magro, Cátia Joana Costa. "Electrodialytic remediation of two types of air pollution control residues and their applicability in construction materials." Master's thesis, Faculdade de Ciências e Tecnologia, 2014. http://hdl.handle.net/10362/12250.
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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente Perfil de Engenharia de Sistemas AmbientaisAir pollution control (APC) residues from municipal solid waste incineration are classified as hazardous waste and disposed of, although it contains potential resources. Due to the different fuel gas cleaning system designs (wet or semi-dry), the APC residues present distinct chemical and physical characteristics that influence the remediation success and their possible reuse. Electrodialytic (ED) process was applied to two types of APC residues aiming their remediation. The characteristics of raw residues and upgraded APC and a broad range of ED experimental conditions were studied (ED cell with – 3 and 2 compartments; 5 or 50 mA of direct current; 3, 7 and 14 days of remediation time). Obtained results showed that remediation was very difficult but the use of low level direct current promoted the immobilization of the heavy metals. The leaching behaviour, for instance, of Pb was avoided in wet system, while the remaining values were kept below the Danish regulation thresholds, with a few exceptions. Still, after 14 days of ED process the best removal rates achieved were: 84% of Cd, 67% of Pb, 67% of Zn, 30% of Cu and 21% of Cr. Thus, 5% of Ordinary Portland Cement was replaced by APC residues in mortars, with or without ED pre-treatment. Porosity, density, compressive strength, heavy metals leaching and chloride were tested. After analysing the parameters, it is possible to say that for the wet gas cleaning systems use a pre-treatment before the reuse in building materials is the best option, since the values for heavy metals leaching tests decrease after, and compressive strength are comparable to material without residue. However, for semi-dry cleaning gas systems, the heavy metals leaching after pre-treatment appears to increase, so for this type of APC it is thus possible to aggregation only of the raw residue. The results of this study suggest new possibilities for this APC waste reuse, presenting great advantages in the waste management system as well as for resource conservation.
ELECTROACROSS - Electrokinetics across disciplines and continents: an integrated approach to finding new strategies for sustainable development (FP7-PEOPLE- 2010-IRSES-269289) and PTDC/ECM/111860/2009 - Electrokinetic treatment of sewage sludge and membrane concentrate: phosphorus recovery and dewatering
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Shikoyeni, Hilya Ndeapo. "Exploring the psycho-social determinants of heavy alcohol drinking amongst women in Oshana, Namibia." University of the Western Cape, 2016. http://hdl.handle.net/11394/5621.
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Magister Artium (Social Work) - MA(SW)Heavy alcohol drinking is a serious health concern in many African countries such as Namibia and South Africa. The heavy use of alcohol is mainly due to avoid coping with the realities of life. There is however, a paucity of research on heavy alcohol use amongst women, particularly in Oshana region of Namibia, where problem drinking is threatening the well-being of women and society. This study explored the psycho-social determinants of women who are heavy alcohol users in the Oshana region. The study design was explorative and descriptive within a qualitative approach. The social constructionist theory underpinned this study. Four participants were randomly selected from the Developmental Social Services caseload which led the researcher to snowball the other four participants for a total of eight participants in the study. Data was collected by means of semi-structured face-to-face interview with the aid of an interview guide. Interviews were transcribed verbatim and field notes were taken. Thematic analysis was used to analyse and interpret the data. The participants identified with coping with realities among women heavy drinking. They reported psychological and social factors affected the well- being of women drinking. These factors included poverty, unemployment, family pressure or influence, availability and accessibility of alcohol, expression, stress, low self-esteem, fear of loneliness and many others. Based on these results, some of the suggestions put forward by all the participants and the researcher concluded the study with a recommendation that an awareness can be created by service providers such as social workers working with women who are heavy drinkers to establish and improve alcohol programmes in Oshana Region and Namibia as a whole.
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Mallikarachchi, Thanuja D. "Exfiltration Trenches for Post Construction Storm Water Management for Linear Transportation Projects: Site Investigation on Metal Removal." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1337908088.
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Kumirai, T., and D. C. U. Conradie. "Thermal performance of heavy-weight and light-weight steel frame construction approaches in the central Pretoria climate." Journal for New Generation Sciences, Vol 11, Issue 3: Central University of Technology, Free State, Bloemfontein, 2013. http://hdl.handle.net/11462/645.
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Published ArticleThe purpose of this paper is to analyse the thermal performance of two buildings. The one has a large thermal mass and the other a highly insulated low thermal mass. A typical 120 m2 suburban building was modelled in Ecotect. As part of the model infiltration rate, wind sensitivity and a central Pretoria weather file were used. New material composites were introduced in the materials database to represent typical building materials used in the construction of heavy and light-weight buildings in South Africa. The thermal characteristics of these new materials were then calculated within Ecotect. Ecomat was used to calculate thermal lag which was used as an additional input into Ecotect. The research indicates that a low thermal mass and highly insulated building have been shown to use 18.3% less annual space heating and cooling energy when compared to the high thermal mass building. The good thermal performance results of the light-weight building will help in clearing scepticism to adopting this construction technology in southern Africa where high thermal mass masonry is still predominant.
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Hobson, Peter Robert. "The design and construction of a holographic film measuring machine for the heavy-liquid bubble chamber HOBC and a determination of the cross section for charm production by 360 GeV protons." Thesis, Brunel University, 1985. http://bura.brunel.ac.uk/handle/2438/9984.
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Heidari, Haratmeh Bardia. "New Framework for Real-time Measurement, Monitoring, and Benchmarking of Construction Equipment Emissions." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/64345.
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The construction industry is one of the largest emitters of greenhouse gases and health-related pollutants. Monitoring and benchmarking emissions will provide practitioners with information to assess environmental impacts and improve the sustainability of construction. This research focuses on real-time measurement of emissions from non-road construction equipment and development of a monitoring-benchmarking tool for comparison of expected vs. actual emissions. First, exhaust emissions were measured using a Portable Emission Measurement System (PEMS) during the operation of 18 pieces of construction equipment at actual job sites. Second-by-second emission rates and emission factors for carbon dioxide, carbon monoxide, nitrogen oxides, and hydrocarbons were calculated for all equipment. Results were compared to those of other commonly used emission estimation models. Significant differences in emission factors associated with different activities were not observed, except for idling and hauling. Moreover, emission rates were up to 200 times lower than the values estimated using EPA and California Air Resources Board (CARB) guidelines. Second, the resulting database of emissions was used in an automated, real-time environmental assessment system. Based on videos of actual construction activities, this system enabled real-time action recognition of construction operations. From the resulting time-series of activities, emissions were estimated for each piece of equipment and differed by only 2% from those estimated by manual action recognition. Third, the actual emissions were compared to estimated ones using discrete event simulation, a computational model of construction activities. Actual emissions were 28% to 144% of those estimated by manual action recognition. Results of this research will aid practitioners in implementing strategies to measure, monitor, benchmark, and possibly reduce air pollutant emissions stemming from construction.Master of Science
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Ricardino, Roberto. "Administração de contrato em projetos de construção pesada no Brasil: um estudo da interface com o processo de análise do risco." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3146/tde-08012008-104811/.
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Tomando por hipótese fatores e habilidades influentes na gestão de projetos e de contratos, esta dissertação tem por objetivo propor um conjunto mínimo de procedimentos que oriente o planejamento da Administração de Contrato, com base no gerenciamento de riscos. Partindo de uma revisão da literatura sobre os processos de administração de contratos e de riscos, o trabalho discute a sua interface e investiga os pontos de vista das partes compradora e vendedora que celebram contratos de obras do setor da construção pesada, aqui representadas por duas organizações com forte presença no mercado brasileiro. Também é apresentado e discutido um método de análise e estruturação de contratos. O trabalho revela os principais requisitos do planejamento da Administração de Contrato.Assuming influential factors and skills on project and contract management, the aim of this dissertation is to propose a minimum set of procedures to serve as guidance on Contract Administration planning, based on risk management. Grounded in a review of the literature on contract and risk management processes, this work discusses its interface and examines the viewpoints of the buying and selling parties that sign contracts of projects in the heavy construction industry, herein represented by two companies that play a significant role in the Brazilian market. In addition, a contract analysis and structuring method is presented and discussed. This work shows the main requirements of Contract Administration planning.
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Alwakiel, Heba Naguib. "Leveraging Weigh-In-Motion (WIM) Data to Estimate Link-Based Heavy-Duty Vehicle Emissions." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/247.
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This research examines the use of archived weigh-in-motion (WIM) data to estimate link-based heavy-vehicle emissions for Oregon highways. This research combined data on vehicle speed, highway grade, and gross vehicle weight and relationship between these elements in published research to estimate the carbon dioxide (CO2) and nitrogen oxide (NOx) emissions from trucks. Sensitivity analysis was conducted on the impact of uphill grade and gross vehicle weight on truck speed and emissions. The results suggest that with the data available in the weigh-in-motion archive and with a reasonable set of assumptions, link-based emissions for heavy-duty vehicles can be estimated. The carbon dioxide (CO2) and nitrogen oxide (NOx) emissions are found to increase when the speed, gross vehicle weight, or road grade increases. The relationship between nitrogen oxide (NOx) emissions and vehicle weight was estimated to be linear. The potential to estimate the link-based heavy-vehicle emissions for Oregon highways using the weigh-in-motion data archive, which was mainly designed to estimate truck counts, has a great value in setting new measures to mitigate the heavy-vehicle emissions.
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Claggett, Christopher L. "An analysis of the prevalence of musculoskeletal disorders in heavy, civil construction operations and the impact of job, age, and experience." Online version, 2002. http://www.uwstout.edu/lib/thesis/2002/2002claggettc.pdf.
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Carlson, Patrik, and Glenn Karjalainen. "Sustainability in the heavy construction equipment industry : A study comparing the tensions between economic and environmental criteria during the acquisition process." Thesis, Karlstads universitet, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-70907.
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Glimbeck, johan, and Olle Ingemarsson. "Steel vs Composite, Heavy vs light : Sustainability in construction - a case study investigating two concrete form work systems uning a MCDMmethod." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-41356.
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This Bachelor thesisis a comparison of two different concrete forms viewed from a sustainable perspective by using a Multi Criteria Decision Making(MCDM)method. Sustainability is a broad concept, often degraded in threepartswhich are financial-,environmental-and socialsustainability. This Bachelor thesisstrives to determine what sustainability is when it comes to monolithic concrete casting in Sweden. In this Bachelor thesissustainabilityhas been degraded in threeparts, financial-,environmental-and work environmental sustainability.Although,the two different forms fill the same function, they differ in many areas. The first one, TRIO,is made of steel and plywoodand is heavy, loud, with a big area and in need of a crane to be able toassemblethe form. The second one, DUO,is made from the composite materialPolytech and isalmost soundless, with a smaller area and lightweight tobe able to be used without crane. The purpose of the MCDM-methodis to create a tool with the purpose of facilitating the choice of concrete forms for monolithic casting while taking sustainability into account. The tool is to ease the decision in building production for both the contractor and for designers. The Bachelor thesisis a case study with both qualitative and quantitative methods.To make a fair comparison between the two forms in this Bachelor thesis,a fictitious project is created toevaluate different criteria for sustainability in design and production. This is doneunder the same premises to be able to obtain an equivalent result.In the fictitious project it turned out that TRIO was the best choice from work environment and economic sustainability, from environmental sustainability it turned out that DUO was the best. Furthermore, it has been difficult to obtain full validity in the MCDM method, all criteria have not been fulfilled inthe environmental field. The environmental area has been the most difficult to investigate and to obtain relevant data in.MCDM has good opportunities to provide great benefit if there were more standardized data to put into it. In this work, very much work was done for a small result.
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Palomino-Valles, A., M. Tokumori-Wong, P. Castro-Rangel, C. Raymundo-Ibañez, and F. Dominguez. "TPM Maintenance Management Model Focused on Reliability that Enables the Increase of the Availability of Heavy Equipment in the Construction Sector." Institute of Physics Publishing, 2020. http://hdl.handle.net/10757/652482.
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The purpose of this paper is to present a maintenance study focused on total productive maintenance (TPM) and reliability-centered maintenance (RCM). Its approach is based on the first pillars of TPM, preventive and autonomous maintenance, as well as the FMEA analysis of RCM for maintenance analysis, which was conducted in this study. The implementation of TPM was successful in that various preventive maintenance (PM) policies assigned to the assets were implemented and it was demonstrated that TPM application in the construction industry could reduce the excessive accumulation of maintenance with the same effective optimization, and with support from RCM analysis and its heavy equipment systems analysis. Excessive corrective maintenance accounts for high investment and delay rates in work times of the assigned project. Traditional methods of availability guarantee, such as reactive or routine maintenance, are insufficient to satisfy a heavy equipment maintenance plan; therefore, what is called for is the systematic application of RCM and TMP because they allow the selection and application of effective PM tasks. An approach that develops and thoroughly analyzes the strategies of continuous corrective and PM is used with an atmosphere of uncertainty and with operational data limited by criticism. Results show a 90% improvement in availability.Revisión por pares
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O'Bannon, Colin Andrew. "“Innumerabyll Shotying of Gunnys and Long Chasyng One Another:” Heavy Artillery and Changes in Shipbuilding in Northern Europe in the Early Modern Period." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1323121842.
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Katrík, Peter [Verfasser], Dieter [Akademischer Betreuer] Hoffmann, and Christina [Akademischer Betreuer] Trautmann. "Activation analysis of heavy ion accelerator constructing materials and validation of beam-loss criteria / Peter Katrík ; Dieter Hoffmann, Christina Trautmann." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2017. http://d-nb.info/1140586688/34.
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Hallberg, Lyggemark Hillevi. "Designing for an autonomous future : How to support and maintain trust through PSS design with an emphasis on heavy construction equipment worksites." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13471.
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Vad som har gjort dagens autonoma teknologi möjlig och som lagt grunden till dess hastiga framsteg har varit den tekniska utvecklingen i datorhårdvara. I takt med att datorer har ökat i både prestanda och hastighet och samtidigt minskat i pris har autonoma lösningar ökat extremt mycket i nästan alla scenarios av vårt vardagsliv där människa-maskinsystem finns. Automation har också spridit sig till fordonsutvecklingen; förarlösa bilar kan redan ses på gatorna och i gruvindustrin används redan autonoma dumpers i viss utsträckning. Det är bara en tidsfråga innan fullt autonoma tyngre maskiner entrar scenen med målet att fortsatt öka produktiviteten i samhället. Men då den autonoma teknologin blir mer och mer komplex så finns det en del som verkar bli viktigare; tillit. Tillit behövs i alla situationer där det inte är möjligt att förstå alla inblandade faktorer. Tillit fungerar som en guide i beslutsfattning och är en förutsättning som är nödvändig för att automation överhuvudtaget ska användas. Men är tilliten för hög eller för låg kan det resultera i att automationen används felaktigt med eventuellt farliga sitationer som påföljd. I den här rapporten definieras autonomi och tillit för att sedan få en djup förstående för de båda för att kunna se sambanden emellan dem. Resultatet i denna rapporten är ett set klart definierade kritiska faktorer som behövs på en arbetsplats där både tunga maskiner och människor vistas. Detta för att skapa och upprätthålla tillit. Dessa kritiska faktorer är sedan satta i en begreppsmässig modell för byggande av tillit och senare exemplifierade in ett system som är utvecklat i ett större sammanhang. Det finns också rekommendationer för hur dessa kritiska faktorer kan få stöd genom product- och tjänstesystems innovation. Den här rapporten visar att det inte är en exakt vetenskap att designa för automation eftersom det finns många avgränsningar att ta hänsyn till som t.ex. kulturella och individuella skillnader hos individen som kan påverka vid interaktionen av autonom teknologi. När man designar för lämplig tillit i autonom teknologi behövs hela systemet tas i åtanke med både människor, maskiner och miljön de vistas i.What has made the autonomy of today possible and what laid the foundation of its rapid advancement has been the technical development in computer hardware. As computers have increased in power and speed and at the same time decreased in price, autonomous solutions has increased enormously in nearly all scenarios of life where human-machine systems can be found. Automation has also started to spread into vehicle technology; driverless cars can be seen roaming the streets and the mining industry, autonomous haulers are already in use to some extent. It is just a matter of time before fully automated heavy machinery enters the scene with the goal further increase the productivity in our society. But when autonomy gets more and more complex, there is one thing that seems so get more important; trust. Trust is needed in situations where a total understanding of all factors involved is hard to grasp. It will act as a guide in decision-making and is a prerequisite that needs to exist if the automation is to be used. Although, if the trust is too high or low the result could be that automation is used inappropriately with possible dangerous situations as an outcome. In this thesis autonomy and trust gets defined and understood and then intertwined to get an understanding of how they are related. The outcome from this thesis is a set of clearly defined crucial factors that is needed on a worksite with heavy equipment machinery and humans to create and maintain trust. These crucial factors are put in a conceptual model of trust building and later exemplified in a system solution created in a larger context. There are also recommendations on how to support these crucial factors through PSS design. This thesis shows that designing for automation is not an exact science, since there is much delimitation to take into account such as cultural and individual differences in the human being that is subject to the autonomy. When designing for appropriate trust in automated technology it needs to be done by taking the whole system into account with humans, machines and the environment they are in.
ME310 Design Innovation at Stanford University
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Bui, Manh-Tuan. "Vision-based multi-sensor people detection system for heavy machines." Thesis, Compiègne, 2014. http://www.theses.fr/2014COMP2156/document.
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Ce travail de thèse a été réalisé dans le cadre de la coopération entre l’Université de Technologie de Compiègne (UTC) et le Centre Technique des Industries Mécaniques (CETIM). Nous présentons un système de détection de personnes pour l’aide à la conduite dans les engins de chantier. Une partie du travail a été dédiée à l’analyse du contexte de l’application, ce qui a permis de proposer un système de perception composé d’une caméra monoculaire fisheye et d’un Lidar. L’utilisation des caméras fisheye donne l’avantage d’un champ de vision très large avec en contrepartie, la nécessité de gérer les fortes distorsions dans l’étape de détection. A notre connaissance, il n’y a pas eu de recherches dédiées au problème de la détection de personnes dans les images fisheye. Pour cette raison, nous nous sommes concentrés sur l’étude et la quantification de l’impact des distorsions radiales sur l’apparence des personnes dans les images et nous avons proposé des approches adaptatives pour gérer ces spécificités. Nos propositions se sont inspirées de deux approches de l’état de l’art pour la détection des personnes : les histogrammes de gradient orientés (HOG) et le modèle des parties déformables (DPM). Tout d’abord, en enrichissant la base d’apprentissage avec des imagettes fisheye artificielles, nous avons pu montrer que les classificateurs peuvent prendre en compte les distorsions dans la phase d’apprentissage. Cependant, adapter les échantillons d’entrée, n’est pas la solution optimale pour traiter le problème de déformation de l’apparence des personnes dans les images. Nous avons alors décidé d’adapter l’approche de DPM pour prendre explicitement en compte le modèle de distorsions. Il est apparu que les modèles déformables peuvent être modifiés pour s’adapter aux fortes distorsions des images fisheye, mais ceci avec un coût de calculatoire supérieur. Dans cette thèse, nous présentons également une approche de fusion Lidar/camera fisheye. Une architecture de fusion séquentielle est utilisée et permet de réduire les fausses détections et le coût calculatoire de manière importante. Un jeu de données en environnement de chantier a été construit et différentes expériences ont été réalisées pour évaluer les performances du système. Les résultats sont prometteurs, à la fois en terme de vitesse de traitement et de performance de détectionThis thesis has been carried out in the framework of the cooperation between the Compiègne University of Technology (UTC) and the Technical Centre for Mechanical Industries (CETIM). In this work, we present a vision-based multi-sensors people detection system for safety on heavy machines. A perception system composed of a monocular fisheye camera and a Lidar is proposed. The use of fisheye cameras provides an advantage of a wide field-of-view but yields the problem of handling the strong distortions in the detection stage.To the best of our knowledge, no research works have been dedicated to people detection in fisheye images. For that reason, we focus on investigating and quantifying the strong radial distortions impacts on people appearance and proposing adaptive approaches to handle that specificity. Our propositions are inspired by the two state-of-the-art people detection approaches : the Histogram of Oriented Gradient (HOG) and the Deformable Parts Model (DPM). First, by enriching the training data set, we prove that the classifier can take into account the distortions. However, fitting the training samples to the model, is not the best solution to handle the deformation of people appearance. We then decided to adapt the DPM approach to handle properly the problem. It turned out that the deformable models can be modified to be even better adapted to the strong distortions of the fisheye images. Still, such approach has adrawback of the high computation cost and complexity. In this thesis, we also present a framework that allows the fusion of the Lidar modality to enhance the vision-based people detection algorithm. A sequential Lidar-based fusion architecture is used, which addresses directly the problem of reducing the false detections and computation cost in vision-based-only system. A heavy machine dataset have been also built and different experiments have been carried out to evaluate the performances of the system. The results are promising, both in term of processing speed and performances
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Wilde, Kristoffer G. "Cloning of cDNAs encoding for anti-WPBR monoclonal antibody (light and heavy chains) and construction of a scFv for expression in E. coli." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37420.pdf.
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Bouali, Emna. "Formulation des bétons lourds , Application dans les fondations profondes." Thesis, CY Cergy Paris Université, 2020. http://www.theses.fr/2020CYUN1055.
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Les bétons lourds sont des bétons spéciaux de haute densité qui dépasse les 3000 kg/m3 comparativement aux bétons ordinaires (2350 kg/m3). Généralement, ils sont utilisés comme des écrans de protection contre les rayonnements ionisants au niveau des installations nucléaires ce qui permet de réaliser des ouvrages porteurs assurant une protection contre les rayons Gamma et d’autres rayons radioactifs. Ils sont utilisés aussi comme des lests dans les applications nécessitant un contre poids important. Des granulats de forte densité sont utilisés pour la fabrication de ces bétons comme la barytine (sulphate de baryum), l’hématite et la magnétite (minerais à base d’oxydes de fer), des déchets ferreux, grenailles de fer ou d’acier… grâce aux propriétés particulières qui les caractérisent tel que la haute densité, la faible abrasivité et la neutralité chimique. Cette étude porte sur l’influence de ces additions utilisées sur le comportement rhéologique (viscosité plastique et seuil de cisaillement) et mécanique des bétons lourds confectionnés. Les résultats obtenus ont montré que l’augmentation du pourcentage d’ajout d’addition (de 38% jusqu’à 54%) provoque une augmentation de la viscosité plastique et du seuil de cisaillement. L’objectif principal de cette présente recherche, est d’étudier la faisabilité d’utiliser ces bétons lourds dans les fondations profondes et plus précisément dans le bétonnage des pieux forés. Afin de répondre à cet objectif, un dispositif équivalent reproduisant à échelle réduite le bétonnage des pieux forés et permettant donc d’établir des corrélations entre la mise en place du béton avec le dispositif proposé et la mise en place réelle du béton sur les chantiers, a été mis en place. Plusieurs configurations de fixation du tube plongeur ont été étudiées. L’ensemble des résultats obtenus a permis de régler la hauteur de fixation du tube plongeur à 15 cm du fond du pieu afin de favoriser la sortie du premier béton et l’évacuation du fluide de forage. Des simulations numériques de l’écoulement d’un fluide à seuil en présence d’un deuxième fluide ont étés réalisées en utilisant COMSOL Multiphysics. L’influence des paramètres rhéologiques et de la densité des bétons utilisés dans le bétonnage des pieux a été étudiée à travers ces simulations. Il a été montré que l’augmentation du béton utilisé (de 2435 kg/m3 à 3064 k/m3) augmente le volume de fluide évacué c’est-à-dire, plus le béton est dense plus, il arrive à chasser le fluide et le remplacer dans le tube.MotsHeavy concretes are special concretes of high density, which is almost 3000 kg/m3 instead of 2350 kg/m3 in the case of ordinary concretes. Usually, they are used as shields against ionizing radiation at nuclear facilities, which allows the construction of load-bearing structures providing protection against Gamma and other radioactive rays. They are also used as ballast in structures requiring a high weight. Aggregates and heavy additions are used for the manufacture of these concretes such as barite, hematite, magnetite, ferrous waste, granules of iron and steel, thanks to their particular properties such as high density, low abrasivity and chemical neutrality. This study deals with the influence of these additions used on the rheological (plastic viscosity and yield stress) and mechanical behavior of the heavy concretes made in order to highlight the effect of the density of the additions on the behavior of the concretes. The results obtained showed that the increase in the addition percentage (from 38% to 54%) causes an increase in the plastic viscosity and the yield stress. The main objective of this research is to study the feasibility of using these heavy concretes in deep foundations specifically in the concreting of bentonite-bored piles. In order to meet this objective, equivalent tests have been set up through the development of a device that simulates the concreting techniques applied at construction sites. Numerical simulations of concreting bentonite-bored piles have been performed using Comsol Multiphysics, through which the influence of rheological parameter and density of concretes was studied. It has been shown that increasing the concrete density from 2435 kg/m3 to 3064 kg/m3, increases the evacuated volume of drilling fluid
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Andersson, Ingo, and Joel Garbers. "Developing Primary Controls for Multiple CE-Machines in a Teleoperation's Environment." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-49372.
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Background: An intermediate step towards fully autonomous construction equipment is “assisted tele-remote operation”. These sorts of operations imply that an operator remotely supports machines that has encountered a situation that autonomous systems onboard the construction machines (CM) cannot solve. Considering teleoperators are not required to continuously monitor the CM in an assisted tele-remote environment, multiple construction machines can be teleoperated simultaneously. For simplification, “assisted tele-remote operation” will now be referred to as “teleoperations”. Volvo Construction Equipment is currently exploring the possibility to teleoperate wheel loaders, articulated haulers, and excavators from a single platform. To do this, primary controls adapted for operating these machines are needed. The primary controls should be designed with the needs of a teleoperator in mind while taking functionality into account, which is needed when CM are both operated conventionally and in tele-remote applications. This procedure will be referred to as relevant primary controls. As the primary controls from three different CM-types are destined to be combined into one platform, the teleoperations platform will be referred to as “3-1 CM teleoperations platform”. The purpose of this thesis project was to propose a relevant solution to primary controls for a 3-1 CM teleoperations platform. To fulfil this purpose, the following two research questions (RQ) where formulated: • RQ1: What are the challenges for teleoperating construction equipment? • RQ2: What defines primary controls in a 3-1 CM teleoperations platform and how can the layout be improved? Method: Using interviews, observations, and literature as qualitative data collection methods, several insights where gained. A scenario for the CM was defined to define the situation in which the quantitative data collection method would be performed. Needs of current CM operators combined with teleoperators have been analysed and listed. Quantitative data has been collected and analysed to design the layout of the primary controls using the objective data as a basis. Result: The research questions were answered with the following results: • RQ1: Insights that resulted in several themes describing how teleoperations can be developed by looking at different challenges it can face. • RQ2: Specifications of the functions included in the new ‘primary controls’ based on CM functions from the company and from teleoperating experiences from several industries. An analysis on how often the functions for the new ‘primary controls’ were used, was carried out. The answers to the research questions were used as a basis to fulfil the purpose of this thesis project by proposing a conceptual solution for primary controls to a teleoperation’s platform for operating multiple CM. Conclusions: It was established that a 3-1 CM teleoperations platform can be developed towards certain CE-machine types. Moreover, additional analysis with experienced operators of each machine type are needed to improve and verify the most optimal layout of the primary controls and platform. Further research is still required to validate the answers to RQ1 and RQ2.
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KIM, KANGWOOK. "Operational Evaluation of In-Use Emissions and Fuel Consumption of B20 Biodiesel versus Petroleum Diesel-Fueled Onroad Heavy-duty Diesel Dump Trucks and Nonroad Construction Vehicles." NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-12172007-092347/.
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Diesel vehicles contribute substantially to statewide emissions of NOx, an ozone precursor, and to particulate matter. North Carolina Department of Transportation (NCDOT) is conducting a pilot study to demonstrate the use of B20 biodiesel fuel on approximately 1,000 vehicles in selected areas of the state; there are plans to extend the use of B20 fuel to a much larger number of vehicles in all 100 counties in North Carolina. Real-world in-use onroad and nonroad emissions of selected heavy-duty diesel vehicles, including those fueled with B20 biodiesel and petroleum diesel, were measured during normal duty cycles using a portable emissions measurement system (PEMS). Each vehicle was tested for one day on B20 biodiesel and for one day on petroleum diesel, for a total of 68 days of field measurements. The vehicles were operated by drivers assigned by NCDOT. Each test was conducted over the course of an entire workshift, and there were approximately 2 to 10 duty cycles per shift. Each duty cycle is comprised of a uniquely weighted combination of operating modes based on vehicle speed, acceleration, and typical modes of activities. Average emission rates on a mass per time basis varied substantially among the operating modes. Average fuel use and emissions rates increased 26 to 35 percent when vehicles were loaded versus unloaded. The use of B20 instead of petroleum diesel lead to a slight decrease (approximately 2 to 10 percent depending on the vehicle) in NO emission rate and significant decreases (approximately 10 to 30 percent depending on the vehicle) for opacity, HC, and CO, respectively. These trends are similar to nonroad vehicles. Factors that were responsible for the observed variability in fuel use and emissions include: operating mode, vehicle size, engine tier and size, vehicle weight, and fuel. In particular, emission rates were also found to decrease significantly when comparing newer, higher tier vehicles to older ones. Recommendations were made regarding operating strategies to reduce emissions, choice of fuel, and the need for future work to collect real-world duty cycle data for other vehicle types.
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Trask, Catherine Mary. "Balancing efficiencies and tradeoffs in epidemiological field studies : evaluating EMG exposure assessment for low back injury risk factors in heavy industry." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1539.
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In order to investigate the etiology of and evaluate interventions for work-related back injuries, researchers need efficient, accurate occupational exposure assessment methods suitable for large samples. The chapters in this thesis examine critical decisions using electromyography (EMG): How should exposure be measured? For what duration? Who should be measured, and how many times?
Low-back EMG, or muscle activity data, was collected during 138 full-shift field measurements over 30 different job titles at 50 different worksites in 5 heavy industries: forestry, transportation, wood products, construction, and warehousing. Observations and self-reports of posture, manual materials handling (MMH), and driving exposures were collected concurrently.
1) Variability of EMG calibration measurements was investigated on right/left sides, multiple trials, 4 positions, and pre/post-shift. Position accounts for the majority of explained variability; there is little to gain by measuring multiple trials or pre- and post-shift, but measuring both sides and multiple positions is worthwhile.
2) Observation and self-report data were easier to collect and cheaper than the EMG direct measure. Costs and successful field performance need to be weighed against the added data detail when making choices about exposure assessment techniques for epidemiological studies.
3) Observed and self-reported exposures were used to predict EMG exposure metrics using mixed multiple linear regression models. Regression models using observed variables predicted 43-50% of the variability in the EMG metrics, while self-reported variables predicted 21%-36%. The observation exposure model provides a low-cost alternative to direct measurement. The self-reported exposure model should be considered with more caution.
4) Full-shift EMG data was resampled for 4, 2, and 1 hour, and for 10 and 2 minute durations to determine the optimal sampling duration. Bias was consistently low, but shorter durations had higher absolute error, percentage error, and limits of agreement. Durations of 4 and 2 hours may be acceptable but those less than 1 hour had large errors.
5) Components of EMG variance were calculated between- and within-subject, and between- industry, company, job, and post hoc grouping. Resolution, contrast, and exposure-response relationship attenuation were calculated for each grouping scheme. The post hoc scheme had the highest contrast and lowest resolution.
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Silva, Eduardo Caldeira da. "Análise do rima à luz das teorias sobre desenvolvimento sustentável: estudos de casos múltiplos na construção pesada no Brasil." Pontifícia Universidade Católica de São Paulo, 2011. https://tede2.pucsp.br/handle/handle/1016.
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Previous issue date: 2011-10-28Sustainable development consolidates every single day as one of the subjects that arises interest from the scientific community, although such topic is propelled not as fast as the serious environment degradation process. In Brazil, environmental impact reports EIR (RIMA, in Portuguese) are the first instruments adopted to contain degradation. This research work aims at evaluate EIR (RIMA) grounded on sustainability theories in the field of economy and management. Multiple case studies were conducted here regarding three projects in hard civil construction in Brazil. The analyzed projects were the hydroelectric plant located in Belo Monte, the rail-station North-South and the highway BR 319/AM, intentionally chosen by their different techniques and by the fact they have a serious impact in the environment. The three cases were selected so as the analysis would not configure the features of one main project, but the one from EIR (RIMA). Such projects are huge in the sector and cause considerable impact both in national economy and the environment. Conclusion sets EIR (RIMA) fragility as well as in responding the minimal legal requests to project licensing, in terms of adherence to economic and organizational tools in sustainable development theory. We hope this research work contributes to propel the discussion on sustainability and to reverse the degradation associated to economic growth
Desenvolvimento sustentável consolida-se dia após dia como um dos temas que mais despertam a atenção da comunidade científica, embora ainda difundido em velocidade inferior à do agravamento da degradação ambiental. No Brasil, os relatórios de impactos ambientais RIMA são o primeiro instrumento para conter a degradação. O trabalho objetiva a avaliação do RIMA à luz das teorias da sustentabilidade, no campo da economia e da gestão. Realizamos estudo de casos múltiplos de três projetos no setor de construção civil pesada, no Brasil. Os projetos analisados foram a hidrelétrica de Belo Monte, a ferrovia Norte-Sul e a rodovia BR 319/AM, propositadamente escolhidos pelas diferenças técnicas e tendo em comum, grande impacto ambiental; escolhemos três casos para que as análises não configurassem apenas as características de um projeto, mas do RIMA. Os projetos do setor são grandiosos e causadores de consideráveis impactos tanto na economia nacional quanto no ambiente. A conclusão aponta para a fragilidade do RIMA, tanto no atendimento ao mínimo legalmente requerido para o licenciamento do projeto, quanto à aderência às ferramentas econômicas e organizacionais existentes na teoria de desenvolvimento sustentável. Esperamos que o trabalho contribua para a difusão da discussão sobre sustentabilidade e para a reversão da degradação associada ao crescimento econômico
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Smith, Brad Steven. "Design and Construction of Pavements in Cold Regions: State of the Practice." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1654.pdf.
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Nascimento, Heider Josué de Aquino. "Reconhecimento de receita e despesa em empresas de construção civil no Brasil: um estudo da aderência às normas contábeis." Pontifícia Universidade Católica de São Paulo, 2007. https://tede2.pucsp.br/handle/handle/1677.
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Previous issue date: 2007-10-15The civil construction activity is one of the most interesting among those performed by human kind, not only because it answers its most basic necessities such as housing, but, also due to its grandness. Hydroelectric plants, roads, ports, airports etc., everything seems extremely grand. In the field of Accounting, the effort to monitor these enterprises also becomes grand, as: How to determine a result that is accrued throughout months or even years? This is the endeavor that International and Brazilian Accounting bodies have already answered. However, another question arises: How adherent are Brazilian civil construction companies to the norms issued by these bodies? Throughout this dissertation, the different niches of civil construction and different accounting standards that exist to answer them will be discoursed. On the other hand, it will also be shown that there are not only different standards to answer these distinct needs, but above all, fiscal norms that conflict with the accounting norms, and it is that conflict that ends up determining the predominance of one norm in detriment of the other. This dissertation is based, primordially, on a field research, that aims to validate which practices are adopted by the companies in that segment in Brazil. Complementing, as technical support, there is a bibliographical review on the main norms and procedures foreseen for this activity in Brazil. The main conclusions point towards a partial adherence to the norms issued by the accounting bodies, by Brazilian civil construction companies, and also different adherences among the researched niches of this activity
A atividade de construção civil é uma das mais interessantes dentre todas as realizadas pela humanidade, não só por ela servir para atender às necessidades mais primitivas como a questão da moradia, mas muito ainda em função da sua grandiosidade. Hidrelétricas, estradas, portos, aeroportos etc., tudo parece extremamente grandioso. No campo da Contabilidade, o esforço para acompanhar estes empreendimentos também se torna grandioso, pois: Como apurar resultados que serão auferidos ao longo de meses ou mesmo de anos? Este é o esforço que os organismos de Contabilidade internacionais e brasileiros já responderam. Entretanto, surge uma outra dúvida: O quanto as empresas brasileiras de construção civil estão aderentes às normas emanadas desses órgãos? Ao longo desta dissertação, será discorrido sobre os diferentes nichos de atuação da construção civil e diferentes normas contábeis existentes para atendê-los. Por outro lado, também será demonstrado que não apenas existem normas diferentes para atender às necessidades distintas, mas, sobretudo, existem normas fiscais conflitantes com as normas contábeis, e é justamente este conflito que acaba por determinar a predominância de uma norma em detrimento de outra. Esta dissertação está pautada, primordialmente, numa pesquisa de campo, que busca validar quais são as práticas adotadas pelas empresas deste segmento no Brasil. Complementarmente, como suporte teórico, existe uma revisão bibliográfica sobre as principais normas e procedimentos previstos para esta atividade no Brasil. As principais conclusões apontaram para uma aderência parcial às normas emanadas pelos organismos contábeis, por parte das empresas brasileiras de construção civil. E foi apresentada uma aderência diferente entre os nichos pesquisados dessa atividade
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Karlsson, Joacim, and Oliwer Dysén. "Vindkraftsfundament i tungbetong : En dimensionerings-, miljö- och kostnadsanalys av tungbetong kontra konventionell betong." Thesis, Uppsala universitet, Tillämpad mekanik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-448038.
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Det här examensarbete har genomförts i samarbete med Sweco Sverige AB på enheten för byggkonstruktion. Syftet med studien var att undersöka tungbetong som ett alternativ till konventionell konstruktionsbetong vid gjutning av vindkraftsfundament. I den här studien har ett vindkraftsfundament i konventionell konstruktionsbetong stått som grund för de dimensioneringsberäkningar som har utförts för att istället kunna använda tungbetong i fundamentet. Ett mål med studien var att med ett fundament i tungbetong minska dimensionerna och således minska klimatpåverkan och kostnaden. För att undersöka om målet kunde uppnås har beräkningar för fundamentets geometri, krav vid bruksgränstillståndet, ekonomiska data och klimatpåverkan utförts. Från studiens dimensioneringsberäkningar om fundamentets geometri framgår det att fundamentet behöver uppfylla vissa krav på mått och därav är fundamentets radie den parameter som kan minska volymen mest. Det ledde till att volymen på fundamentet i tungbetong blev mindre än den för konventionell konstruktionsbetong. Tungbetongens resultat blev ur vissa perspektiv bättre än konventionell konstruktionsbetong. Volymen för tungbetongsfundamentet kunde reduceras med 14 %. Detta resulterade i en minskning av koldioxidutsläpp med 7 %, priset ökade däremot med 65 %. Genom att i detta fall använda sig av tungbetong istället för konventionell betong kunde både volym och koldioxidutsläpp reduceras, däremot till ett väldigt högt pris.The purpose of the study was to investigate an alternative to conventional construction concrete. In this study, a wind turbine foundation consisting of conventional construction concrete have been analysed and served as a basis for dimension calculations to the foundation of heavy weight concrete. A goal with the study was to decrease the dimensions of the foundation using heavy weight concrete instead of conventional and therefore also reduce the climate impact as well as the cost of the foundation. To investigate if the goal is achievable, calculations for the foundation geometry, the requirement of the service limit state, economic data and climate impact have been calculated. In the calculations about the foundation geometry, certain requirements regarding the dimensions needs to be achieved and therefore it is the radius of the foundations that can affect the volume the most. This resulted in a decrease of volume for the heavy weight concrete foundation. In some perspectives, the heavy weight concrete had better outcome than conventional construction concrete. The volume of the foundation could be reduced by 14 %. This led to a reduction in product emission by 7 %. The price of heavy weight concrete, per cubic meter, is almost five times more expensive than it is for conventional construction concrete and therefore the price was 65 % higher. This concludes in a possibility to reduce both the volume as well as the CO2-emissions but for a very high price.
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Hameury, Stéphane. "The hygrothermal inertia of massive timber connstructions." Doctoral thesis, KTH, Byggvetenskap, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4200.
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The work presented in this Doctoral dissertation concerns the ability of heavy timber structures to passively reduce the fluctuations of the indoor temperature and of the indoor relative humidity, through the dynamic process of heat and moisture storage in wood. We make the hypothesis that the potential offered by the hygrothermal inertia of heavy timber structures is significant, and that it could provide a passive way of regulating the indoor climate. This ultimately could results in a decrease of the energy demand from the Heating, Ventilating and Air Conditioning systems. In this Thesis, the author tries to characterise and quantify the significance of the hygrothermal inertia providing by the heavy timber constructions. The experimental studies contain an in-situ measurement campaign carried out at the Vetenskapsstaden building located in Stockholm and erected in 2001. The results from the test campaign show that a heavy timber construction may contribute to buffer the indoor temperature. A direct quantification of the moisture stored in the wood structure is measured regarding the year-to-year indoor humidity fluctuations. It was however hardly possible to directly quantify the moisture storage potential offered by the structure regarding the day-to-day indoor relative humidity fluctuations because of the low sensitivity of the measuring technique used. In regard to the limitations noticed during the in-situ measurements, laboratory measurements were launched to develop new methods to determine the day-to-day hygric performances of wood exposed indoor. A new method based on the Magnetic Resonance Imaging technology was developed and is intended to provide information about the Moisture Buffer Value measured according to a NORDTEST protocol, and about the moisture distribution in wood with high spatial resolution. The Moisture Buffer Value of untreated Scots pine measured with this method is in accordance with the gravimetric method provided by the NORDTEST protocol. The Moisture Buffer Value of coated Scots pine was also investigated and it is normally assumed that any coatings will decrease the Moisture Buffering Capacity of the structure. The results show however that for specific coating such as waterborne alkali silicate coating, the Moisture Buffering Capacity of the structure may on the contrary be improved. At last, numerical simulations were carried out. They were based upon the extension of a modular simulation environment IDA ICE 3.0, with the implementation of a specific model for heat and moisture transport in a wood. The results obtained pinpoint the highly synergetic effects between the indoor moisture loads, the ventilation rate, the outdoor climate and the moisture interactions with the structure. The outcomes also show that the Moisture Buffering Capacity of a heavy timber structure is appreciable. The structure is able to even out substantially the day-to-day indoor relative humidity fluctuations for a certain range of ventilation rate.QC 20100825
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Pettersson, Beatrice, and Carolina Olsson. "Underlag för projektering av ytterväggar : Kvalitativ analys av ytterväggar ur ett livslängdsperspektiv med fokus på fuktsäkerhet, robusthet och kostnad." Thesis, KTH, Byggteknik och design, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-259899.
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Vid projektering av ytterväggar ställs höga krav på funktion och utformning. Ytterväggar har en mängd olika konstruktionslösningar beroende på stomsystem, fasadmaterial och andra förutsättningar. Uppdragsgivaren WSP, vill underlätta kvalitetssäkringen och minska tidsåtgången vid projektering med hjälp av framtagna typdetaljer. Typdetaljerna är utformade med hänsyn till aspekterna fuktsäkerhet, robusthet och kostnad. Intervjuer med konstruktörer, litteraturstudier samt kontakt med produktleverantörer, ligger till grund för arbetet. Utifrån analys av insamlat material har konstruktionslösningar tagits fram utifrån en maximal livslängd. Arbetet har resulterat i två typdetaljer för tung stomme och tre för lätt stomme, med fasadmaterialen puts, tegel samt skivmaterial. Tillhörande teknisk beskrivning, U-värde och kostnadsbild har tagits fram för vardera typdetalj.Moisture saftey; Robustness; Cost; Exterior wall; Light frame; Heavy frame; Construction details Abstract på engelska: Function and design have always been critically important when designing exterior walls. Several designs can be possible but are largely dependent upon the framework system, facade material as well as various other considerations. The client, WSP, wish to guarantee quality whilst reducing planning time but also maintaining factors such as moisture safety, robustness and cost. The basis of the work consisted of interviews with designers, revision of literature and product supplier liaison. Based upon analysis of collected material, the designs have been developed to ensure a maximum life span. The result has produced both heavy and light frame designs by utilising plaster, brick and sheet materials for the facade construction. The relevant technical descriptions, U-values and overall cost estimates have been developed for each construction details.
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Elmehög, Hampus. "Uppföljning av absoluta tjälrörelser : En fallstudie av väg E10 i Kiruna." Thesis, Luleå tekniska universitet, Geoteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-72057.
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Detta examensarbete har haft som mål att undersöka tjällyftningen hos en väg i en fältstudie och utvärdera reliabiliteten hos två olika modeller för skattning av tjällyftning. Modellerna som har studerats är Trafikverkets nuvarande, vilken är implementerad i deras vägdimensioneringsverktyg PMS Objekt, samt segregation potential theory. Den studerade vägsträckan är belägen i Kiruna. I vägen har borrkärneprover tagits och vägens obundna lager, inklusive terassmaterial, har blivit analyserade i laboratorium. Dessa tester inkluderar både geoteknisk klassificering och endimensionella frysförsök på terassmaterialet. Materialets tjälfarlighet har klassificerats enligt både Trafikverkets eget och det amerikanska USACEs system. Alla prover, inklusive terrassmaterialet, består huvudsakligen av grus och sand. Enligt båda de använda klassificeringssystemen bedöms alla prover som icke tjälfarliga. Nivåmätningar utförda på vägen visar dock att tjällyftning ändå förekommer i vägen. Denna tjällyftning har inte kunnat modelleras framgångsrikt i PMS Objekt, där ingen tjällyftning alls fås trots att en dimensionerande vinter tillämpas i analysen. Däremot har en god överensstämmelse mellan bakåträknad och empiriskt beräknad tjälfarlighetsklassificering med SP0-värde enligt segregation potential theory kunnat ses. Även när detta beräknas utifrån utförda frysförsök fås en relativt god överensstämmelse. Studiens främsta fynd är att den visar på att även material som bedöms som ej tjällyftande enligt de två systemen för tjälfarlighetsklassificering faktiskt orsakar tjällyftning och att detta omfattar både terrass- och överbyggnadsmaterial. Studien visar att detta tjällyft främst beror på primärt lyft, varför klassificeringarna stämmer ganska väl om endast det sekundära lyftet avses. Studien har även visat på att Trafikverkets nuvarande modell är otillräcklig när det kommer till att modellera tjällyftning för grovkorniga jordar. Slutligen har studien även visat på möjligheten att bedöma jords tjälfarlighet med hjälp av segregation potential theory, även om också denna metod endast kan användas för att modellera sekundärt lyft.The aim of the master thesis has been to examine the frost heaving of a road in a field study and to evaluate the reliability of two different models for estimation of frost heaving. The studied models are the current one of the Swedish Transport Administration, which is implemented in their road design tool PMS Objekt, and the segregation potential theory. The studied road section is located in Kiruna, in the northern part of Sweden. The road has been cored and the unbound layers of it, including the subgrade, have been analyzed in laboratory. These analyses include both geotechnical characterization and one-dimensional frost heave tests of the subgrade material. The frost susceptibility of the collected material has been classified according to both the Swedish Transport Administrations system and the American USACE’s system. All samples, including the subgrade, consist mainly of gravel and sand. According to both the used classification systems all samples are classified as not frost susceptible. However, the elevation measurements of the road show that frost heaving occurs in it despite this. This heaving has not been possible to model successfully in the program PMS Objekt. In it the frost heave prediction yields no heave at all, despite applying a design winter (worst case) in the analysis. A good conformity has however been observed between back-calculated and empirically evaluated frost susceptibility using segregation potential theory. A quite good conformity has also been observed when the same thing is evaluated from the preformed freeze tests. The most important finding of the study is that even material that is categorized as non-frost susceptible according to the two studied systems actually does heave. This finding includes both subgrade aswell as the unbound material in the superstructure. It has been found that the total frost heave observed in this study originates mainly from primary heaving, meaning the studied systems are quite correct in their frost susceptibility classification if only secondary heaving is intended. The study has also shown that the current model applied in PMS Objekt is poor in predicting the amount of heaving in coarse subgrades. Finally, the study has also shown the possibility to evaluate a soils frost susceptibility using segregation potential theory, although this model aswell is only applicable to secondary heave
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Jalkebo, Charlotte. "Placement of Controls in Construction Equipment Using Operators´Sitting Postures : Process and Recommendations." Thesis, Linköpings universitet, Maskinkonstruktion, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-108980.
Full textAbstract:
An ergonomically designed work environment may decrease work related musculoskeletal disorders, lead to less sick leaves and increase production time for operators and companies all around the world. Volvo Construction Equipment wants to deepen the knowledge and investigate more carefully how operators are actually sitting whilst operating the machines, how this affects placement of controls and furthermore optimize controls placements accordingly. The purpose is to enhance their product development process by suggesting guidelines for control placement with improved ergonomics based on operators’ sitting postures. The goal is to deliver a process which identifies and transfers sitting postures to RAMSIS and uses them for control placement recommendations in the cab and operator environments. Delimitations concerns: physical ergonomics, 80% usability of the resulted process on the machine types, and the level of detail for controls and their placements. Research, analysis, interviews, test driving of machines, video recordings of operators and the ergonomic software RAMSIS has served as base for analysis. The analysis led to (i) the conclusion that sitting postures affect optimal ergonomic placement of controls, though not ISO-standards, (ii) the conclusion that RAMSIS heavy truck postures does not seem to correspond to Volvo CE’s operators’ sitting postures and (iii) and to an advanced engineering project process suitable for all machine types and applicable in the product development process. The result can also be used for other machines than construction equipment. The resulted process consists of three independent sub-processes with step by step explanations and recommendations of; (i) what information that needs to be gathered, (ii) how to identify and transfer sitting postures into RAMSIS, (iii) how to use RAMSIS to create e design aid for recommended control placement. The thesis also contains additional enhancements to Volvo CE’s product development process with focus on ergonomics. A conclusion is that the use of motion capture could not be verified to work for Volvo Construction Equipment, though it was verified that if motion capture works, the process works. Another conclusion is that the suggested body landmarks not could be verified that they are all needed for this purpose except for those needed for control placement. Though they are based on previous sitting posture identification in vehicles and only those that also occur in RAMSIS are recommended, and therefore they can be used. This thesis also questions the most important parameters for interior vehicle design (hip- and eye locations) and suggests that shoulder locations are just as important. The thesis concluded five parameters for control categorization, and added seven categories in addition to those mentioned in the ISO-standards. Other contradictions and loopholes in the ISO-standards were identified, highlighted and discussed. Suggestions for improving the ergonomic analyses in RAMSIS can also be found in this report. More future research mentioned is more details on control placement as well as research regarding sitting postures are suggested. If the resulted process is delimited to concern upper body postures, other methods for posture identification may be used.
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Butkevičius, Saulius. "Sunkiasvorio transporto įtaka automobilių kelių asfaltbetonio dangos funkcionavimo trukmei." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20071204_102534-41160.
Full textAbstract:
Pastaraisiais metais Lietuvoje ženkliai padidėjęs sunkiasvorio transporto eismas sąlygoja ankstyvą daugumos šalies kelių dangų suirtį, nes jau nepakanka esamo jos stiprio. Įvairios asfaltbetonio dangos pažaidos rodo, kad ardoma ne tik danga, bet ir jos konstrukcija – tai didina išlaidas kelių remontui bei priežiūrai, mažėja eismo saugumas bei komfortiškumas. Iki šiol Lietuvoje dar nėra metodikos, kurią taikant būtų galima pakankamai tiksliai įvertinti sunkiasvorio transporto poveikį kelių dangai.
Šiame darbe ištirta sunkiasvorio transporto eismo ardomojo poveikio, įvertinant Lietuvos klimato sąlygas, įtaka kelių dangos asfaltbetonio sluoksnių stipriui ir funkcionavimo trukmei. Pateikta metodika sunkiasvorio transporto eismo ir apkrovų ardančio poveikio Lietuvos kelių dangai, priklausomai nuo eismo sezoniškumo, jos stiprio, asfaltbetonio sluoksnių likutinio stiprio bei kelių dangos įtempto-deformuoto būvio kitėjimo, įvertinti.
Pasiūlytas kelių dangos asfaltbetonio sluoksnių likutinio stiprio ir funkcionavimo trukmės likutinio resurso modelis. Modelis įvertina apkrovos parametrus bei jos poveikio intensyvumą, automobilių srauto sudėtį, kelių dangos sluoksnių medžiagų bei jai stiprinti naudojamų medžiagų projektines savybes, kelių dangos sluoksnio medžiagos stiprio kitėjimą, atsižvelgiant į jos suirties mastą, kelių dangos darbą, esant įvairioms vietovės klimato sąlygoms, skirtingiems žemės sankasos gruntams ir vietovės hidroterminiams rėžimams, remonto darbų kainą bei ekonominį... [toliau žr. visą tekstą]The marked increase of heavy weight vehicle traffic in Lithuania in recent years is the reason for early deterioration of majority road pavements of the country due to inadequate strength of road pavements. Various kinds of damages in asphalt concrete pavements indicate that damage is made not only to a pavement but to its construction as well, which increases costs for road repair and maintenance and reduces road safety and comfort. There is no methodology in Lithuania that would allow to evaluate the impact of heavy weight vehicles on a road pavement with adequate preciseness. This study analyses the impact of damaging effect of heavy weight vehicle traffic on the strength and duration of service life of asphalt concrete layers in a road pavement taking account of climate conditions of Lithuania. A methodology to evaluate the damaging effect of heavy weight vehicle traffic and loads on road pavements in Lithuania depending on seasonal peculiarities of traffic, its strength, remaining strength resource of asphalt concrete layers and changes in stressed or deformed state of a road pavement is presented. A model of remaining strength of asphalt concrete layers in a road pavement and remaining resource of service life was proposed. The model evaluates load parameters and intensity of its impact, composition of vehicle flow, design characteristics of materials in layers of a road pavement and materials used when strengthening it, changes in the strength of layer material in a... [to full text]
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Riera, Elisabeth. "Vers une construction raisonnée d’une nouvelle génération de récifs artificiels : Analyses comparatives des facteurs intrinsèques favorisant leur colonisation de la micro à la macro-échelle." Thesis, Université Côte d'Azur, 2020. http://www.theses.fr/2020COAZ4001.
Full textAbstract:
Les récifs artificiels sont des structures immergées posées délibérément sur le fond marin pour imiter certaines caractéristiques d’un habitat naturel, ils sont utilisés depuis des milliers d’années par les hommes dans le but d’améliorer leurs pratiques de pêches et depuis peu ils sont également employés pour la protection voire la restauration de certains habitats marins. Malgré ces divers objectifs, il réside encore un manque de fondements scientifiques pour déterminer la qualité de ces structures mises à l’eau afin d’en évaluer leur efficacité. Les présent travaux, focalisés sur l’étude de leurs caractéristiques intrinsèques, à savoir leurs matériaux et leurs structuresUn suivi conjugué du biofilm et du macrofouling sur différents substrats, complété par une analyse de leur contenu en métaux lourds a permis de mettre en évidence la qualité de certains substrats utilisé pour la construction de récifs artificiel. Le suivi simple du biofilm s’est révélé être un bon indicateur pour mettre en valeur ces différences de façon simple et rapide pour valider l’utilisation de tel ou tel substrat. Par ailleurs, la mise au point d’une méthode destinée à évaluer la complexité et l’hétérogénéité des récifs artificiels a permis de donner une classification pertinente des différentes structures existantes. Cette méthode standardisée permettra d’évaluer in situ l’influence des paramètres structuraux des récifs artificiels sur le recrutement, l’abondance, la distribution et/ou la diversité. Une première étude à l’échelle microscopique a permis de révéler l’influence de la structure du substrat à la fois sur l’abondance du biofilm et sur l’activité photosynthétique de ces communautés.L’ensemble de ces résultats permet d’offrir un cadre scientifique plus précis pour aborder la construction des récifs artificiels sur le choix de leurs matériaux et de leurs designs. De futures lignes directrices pourraient être émises afin d’optimiser l’efficacité de tout projet d’immersion de récifs artificielsArtificial reefs are submerged structures deliberately placed on the seabed to mimic some characteristics of a natural habitat, they have been used for thousands of years by fishermen to improve their fishing practices and recently they are also used for the protection or even the restoration of certain marine habitats. Despite these various objectives, there is still a lack of scientific fundaments for determining the quality of these submerged structures in order to assess their effectiveness. The present works, focused on the study of their intrinsic characteristics, namely their materials and their structures. A combined monitoring of the biofilm and the macrofouling on different substrates, supplemented by an analysis of their heavy metal content allowed to highlight the quality of certain substrates used for the construction of artificial reefs. Simple monitoring of the biofilm has proven to be an efficient indicator for highlighting these differences to validate the use of a particular substrate.In addition, the development of a method to assess the complexity and heterogeneity of artificial reefs has enabled us to give a relevant classification of the various existing structures. This standardized method will allow to assess in situ the influence of structural parameters of artificial reefs on recruitment, abundance, distribution and/or diversity. A first study at the microscopic scale revealed the influence of substrate structure on both the abundance of biofilm and the photosynthetic activity of these communities.A more precise scientific framework is now available to guide the construction of artificial reefs on the choice of materials and the design of artificial reef structures in order to optimize the effectiveness of artificial reef immersion project