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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Bullerreduktion av hytt på Volvodumprar : Undersökning, mätning och analys / Noise reduction in the cabin of a Volvo articulated hauler : Study, measurement and analysis

Muftic, Armin, Chamoun, Simon January 2010 (has links)
Too high levels of noise lead to various health problems and cost society billions of SEK peryear. In this thesis we have examined a model of the A40E articulated hauler at VolvoConstruction Equipment in Braås. We have tried to reduce cabin noise in an articulated hauler,while also providing a way on how to proceed with a machine when the cabin does not measureup to the sound requirement. The best way to find leaks were with a reference source of model4205 and its speaker HP 1001 from Brüel & Kjaer in the cab and then walk around and listen towhere the reference source was more prominent. In this way, we found that the edges and theplugs were sensitive areas. We managed to reduce cabin noise 2.77 dB(A) at 1900 rpm, byisolating certain areas with glass wool. We have also looked at how certain areas individually canreduce cabin noise. We concluded that the isolation of the following areas gave the bestresponse: Cabin ceiling, cabin floor, cabin door, window edges around the dashboard, torpedowall.
12

Transport Management Services in C200 web server : An approach to integrate interactive services / Transportledningstjänster i C200 webbserver : Ett försök i att integrera interaktiva tjänster

Illanes, Christian January 2015 (has links)
This report studies the possibility of integrating Transport Management Services (TMS) in a low-cost platform called Communicator 200 (C200). The platform is developed by Scania and is a black box that manages vehicle data, positioning, and wireless communication. The C200’s main purpose is to connect a hauler’s vehicles to their office system via wireless links and Internet. The thesis describes the design and implements a prototype of a service called Messaging that is used to send text messages between truck and office. The prototype is evaluated and tested with different web browsers in various hand-held terminals with different screen sizes. The main conclusion is that it is technically possible to integrate TMS in the C200 without altering the platform architecture too much. / Denna rapport undersöker möjligheten att integrera transportledningstjänster i en billig platform kallad Communicator 200 (C200). Platformen är utvecklad av Scania och är en svart låda som hanterar fordonsdata, positionering och trådlös kommunikation. C200 huvudsyfte är att sammankoppla ett åkeris fordon med deras kontorssystem via trådlösa förbindelser och Internet. Rapporten beskriver designen och implementerar en prototyp av en tjänst kallad Messaging som används för att skicka textmeddelanden mellan lastbil och kontor. Prototypen utvärderas och testas mot webbläsare i olika handhållna terminaler med olika skärmstorlekar. Huvudslutsatsen är att det är möjligt att integrera transportledningstjänster i C200 utan att ändra plattformens arkitektur alltför mycket.
13

Post-Acute Serological Response to SARS-COV-2 and Predicting Post COVID-19 Condition (PCC) in Canada

Collins, Erin 05 January 2024 (has links)
Background: Post COVID-19 Condition (PCC, also known as long COVID and post-acute sequelae of COVID-19) is a major public health concern with severe and pervasive impacts on physical and mental health. PCC is highly heterogeneous and may manifest as different clusters of symptoms of varying intensity and duration. The etiology of PCC remains uncertain, though several underlying pathophysiological mechanisms, such as cellular damage, inflammatory cytokines, and a hypercoagulable state, are thought to contribute to PCC inception and trajectory. Examination of potential serological markers of PCC, accounting for clinical covariates, may yield emergent pathophysiological insights. Objectives: Primary objectives of this thesis are to 1) Identify key clinical and potential serological predictors of PCC; 2) Acquire clinical and serological data in a large-scale prospective observational study; 3) Assess relationships between PCC and serological markers, accounting for clinical covariates; 4) Systematically review evidence to date on primary observational studies comparing serological response between people with and without persistent symptoms post COVID-19 recovery; 5) Discuss persisting gaps in knowledge and data quality, and propose strategies for resolve. Methods: This thesis is framed around three core efforts: 1) The design of survey questions and study materials, recruitment of participants, and data collection in a large-scale prospective cohort study launched in 2020; 2) The assessment of relationships between pre-defined serological predictors and PCC, accounting for clinical covariates; and 3) A robust rapid review of PCC onset and phenotype as functions of serological markers. Expert opinion was sought to define serological predictors. Clinical predictors were defined a priori based on systematic reviews meeting AMSTAR 2 guidelines. Conclusions: To address objectives, we described efforts to collect clinical and serological data from a large-scale prospective cohort study; identify PCC-cases and infected-controls; assess associations between pre-defined serological predictors (IgG titres targeting SARS-CoV-2 spike (S), nucleocapsid (N), and receiver binding domain (RBD) antigens, and efficient neutralization) and PCC; and synthesized findings from an extensive rapid review on PCC as a function of serological markers. Our multivariate analysis using Stop the Spread Ottawa data is, to our knowledge, the first Canadian study to report the direction and magnitude of association between selected serological predictors (anti-IgG response to S, N, and RBD SARS-CoV-2 antigens, and neutralizing efficiency) and PCC status and impact on quality of life. Finally, we described five potential strategies which may improve the accessibility, quality, and amalgamation of data pertaining to PCC: 1) Fostering comparability between studies to enable synthesis of multiple datasets; 2) Advancing the characterization and consensus on PCC phenotypes; 3) Employing innovative modelling strategies that could potentially yield novel insights; 4) Promoting robust collaboration and knowledge sharing among research teams; and 5) Engaging people with lived experience at all stages of research.
14

Enclosing and Mounting an Electronic Component on Articulated Haulers : A proposition on how to protect, and where to place, an intelligent node on the environmentally harsh exterior of construction equipment with respect to multiple parameters

Sintorn, Johan January 2016 (has links)
As is the case with many other manufacturers of vehicles, Volvo Construction Equipment has a constantly increasing amount of electric and electronic equipment in their articulated haulers. These are of great use in modern machines, bringing functions, and safety that were not possible before, but they also bring more cables to handle. In the case of the articulated haulers a quite thick cable harness of about 15 meters in length reaches from the driver’s cabin in the front to the components in the far back end of the vehicle. This is not only a lot of long cables to handle both during assembly and service, but the nature of signals traveling in cables is that the voltage gets weaker with distance. This phenomenon has to be accounted for by measuring devices dependent on the voltage. It has been suggested that a device referred to as an intelligent node, or ICCS-module, which communicates digitally via CAN could be installed in the back of the articulated haulers. This module would be independent of the mentioned drop in voltage. The ICCS-module will be receiving a small bundle of cables being routed from the driver’s cabin. From it cables would go out to a majority of the components in its vicinity. The components connected to the node would not need to have any other cables. This thesis is focused on the mechanical aspects of installing this ICCS-module. Having electric and electronic equipment on construction vehicles is a challenge when it comes to protecting the device from the harsh environment that is the hauler’s exterior. It will have to withstand being immersed in water for long periods of time, greatly varying temperatures, vibrations and shocks as well as being hit by projectiles. The placement as well as the design of the enclosure should be chosen with respect to both the devices length of life and how well it fulfils its intended role and achieves the expected results. To produce an enclosure and find a placement aiming to satisfy these conditions, a traditional product development process were executed. The articulated haulers as well as relevant literature were researched. Concepts were generated and evaluated by both the author and by employees at Volvo Construction Equipment until a final concept for the enclosure and placement were found. The enclosure were then designed in detail specifying the material, manufacturing techniques, controlled for thermodynamic circumstances, modelled in Catia V5 and controlled for vibrations. It was concluded that the enclosure should be able protect the ICCS-module after some more development and that the placement and cable routing results in a much shorter total cable length.
15

Moduluppbyggnad av ramstyrda dumprar ur ett produktionsperspektiv – Volvo CE AB i Braås / Module construction of articulated haulers through a production perspective – Volvo CE AB in Braås

Skoog, Johanna, Nagy, Thomas January 2006 (has links)
Denna rapport i form av examensarbete för utbildningsprogrammet Managing Technology and Business Projects, är en del i Volvos framtida produktions-/ produktstrategier. Uppsatsens syfte är att ur ett produktionsperspektiv understödja Volvo Construction Equipment i Braås i strävan mot en ökad modulindelning av ramstyrda dumprar, som en del i utvecklingsarbetet för en effektivare produktion. Resultat har uppnåtts genom analys av intern och extern benchmarking jämfört med den teori som finns inom ämnesområdet modulindelning. Huvudresultatet visar att teorin och verkligheten skiljer sig genom att modulindelning ska anpassas individuellt utifrån varje företag och inte fungerar som en generellt applicerbar process. Slutsatsen visar att Volvo CE i Braås måste utveckla en egen handlingsplan och kravspecifikation utifrån egna definitioner som är skräddarsydda specifikt för företaget. I rapporten presenteras förslag till ovanstående handlingsplan för modulindelning på Volvo CE i Braås. / This diplomawork is the ending part of the education program Managing technology and Business Projects at Växjö University and was given as an assignment from Volvo Construction Equipment in Braås. The work is a part of Volvos future production- and product strategies and aims to support Volvo in their work towards a module classification of the articulated hauler line built in Braås. The result has been reached trough analysis of internal and external benchmarking compared to the theory regarding the subject. The main result shows that theory diverges from reality in the way that modularization must be adjusted individually for each company and that it doesn’t work as a general applicable process. The conclusion shows that Volvo CE in Braås must develop a unique plan of action from the in-house definitions that is tailored specifically for the company.
16

Moduluppbyggnad av ramstyrda dumprar ur ett produktionsperspektiv – Volvo CE AB i Braås / Module construction of articulated haulers through a production perspective – Volvo CE AB in Braås

Skoog, Johanna, Nagy, Thomas January 2006 (has links)
<p>Denna rapport i form av examensarbete för utbildningsprogrammet Managing Technology and Business Projects, är en del i Volvos framtida produktions-/ produktstrategier.</p><p>Uppsatsens syfte är att ur ett produktionsperspektiv understödja Volvo Construction Equipment i Braås i strävan mot en ökad modulindelning av ramstyrda dumprar, som en del i utvecklingsarbetet för en effektivare produktion. Resultat har uppnåtts genom analys av intern och extern benchmarking jämfört med den teori som finns inom ämnesområdet modulindelning. Huvudresultatet visar att teorin och verkligheten skiljer sig genom att modulindelning ska anpassas individuellt utifrån varje företag och inte fungerar som en generellt applicerbar process. Slutsatsen visar att Volvo CE i Braås måste utveckla en egen handlingsplan och kravspecifikation utifrån egna definitioner som är skräddarsydda specifikt för företaget.</p><p>I rapporten presenteras förslag till ovanstående handlingsplan för modulindelning på Volvo CE i Braås.</p> / <p>This diplomawork is the ending part of the education program Managing technology and Business Projects at Växjö University and was given as an assignment from Volvo Construction Equipment in Braås.</p><p>The work is a part of Volvos future production- and product strategies and aims to support Volvo in their work towards a module classification of the articulated hauler line built in Braås.</p><p>The result has been reached trough analysis of internal and external benchmarking compared to the theory regarding the subject. The main result shows that theory diverges from reality in the way that modularization must be adjusted individually for each company and that it doesn’t work as a general applicable process. The conclusion shows that Volvo CE in Braås must develop a unique plan of action from the in-house definitions that is tailored specifically for the company.</p>
17

Monitored Neural Networks for Autonomous Articulated Machines / Monitored Neural Network for Curvature Steering of Autonomous Articulated Machines

Beckman, Erik, Harenius, Linus January 2020 (has links)
Being able to safely control autonomous heavy machinery is of uttermost importance for the conversion of traditional machines to autonomous machines. With the continuous growth of autonomous vehicles around the globe, an increasing effort has been put into certifying autonomous vehicles in terms of reliability and safety. In this thesis, we will investigate the problem with a deviation from the planned path for an autonomous hauler from Volvo Construction Equipment. The autonomous hauler has an error within the kinematic model, the feed-forward curvature-steering controller, due to a slip-effect that comes with the third wheel-axle. The deviation can especially be seen in sharp curves, where the deviation needs to be decreased in order to make the autonomous hauler more dependable and achieve an increased accuracy when following any given path. The aim of the thesis is to develop a fully functional Artificial Neural Network that has a new steering angle as output. The hypothesis for this thesis is to use an ANN to mimic the steering of a human driver, since a real driver compensates for the slipping behavior; both because the operator knows where on the road the machine is and also in the way that a human thinks many steps ahead whilst driving. This proposed ANN will have a monitor function which ensures that the steering angle command operates within its boundaries. Hence this thesis implies that it is indeed possible to ensure that the ANN performs reliably with the help of a monitor function in a simulated environment and can thus be used in dependable systems.
18

The load carrying unit of articulated haulers : Analysis of the welded connections

Lindholm, Martin, Uçar, Metin, Dzanic, Nermin January 2009 (has links)
Detta examensarbete handlar om finita element analys av svetsade förband i korgen på Volvo dumpern A40E. Det genomfördes i samarbete med Volvo CE i Braås. Uppgiften var att ge företaget en lämplig lösning för att minska mängden svetsskarvar på den främre delen av lastenheten. För att uppnå detta har en rad analyser genomförts med hjälp av CATIA och ANSYS på både de befintliga och de justerade (potentiella ersättare) svetsade förbanden. Analyserna visar att utmatningshållfastheten av svetsade förband huvudsakligen beror på inbränningsdjupet. Med andra ord, förstärka svetsförband genom större inbränning är mer fördelaktigt än att använda mer svets på utsidan. Slutsatsen blev att både produktionstid och kostnad kan minskas genom justering av de svetsade förbanden. Eftersom svetsförband på lastenheten är sammankopplade bör mer omfattande studier som inkluderar alla svetsar genomföras för att uppskatta effekterna av liknande justeringar. / The work presented in this master thesis is about the finite element analysis of the welded connections in load carrying unit of the articulated hauler, Volvo A40E. It was performed in cooperation with Volvo CE in Braås. The task was to provide the company with an appropriate solution to reduce the amount of weld used on the front part of the load carrying unit. To accomplish this, a series of analyses utilising CATIA and ANSYS was performed on both existing and adjusted (potential replacement) welded connections. The analyses brought to light the fact that the fatigue resistance of welded connections significantly depends on the penetration depth. In other words, reinforcing the welded connections by deeper penetration is more beneficial than providing support from outside through thicker weld. It was concluded that applying adjusted welds lessens both the production time and cost. Nevertheless, since the welds on the load carrying unit are correlated; more extensive studies covering all welds should be carried out to estimate the impacts of similar replacements.
19

The load carrying unit of articulated haulers : Analysis of the welded connections

Lindholm, Martin, Uçar, Metin, Dzanic, Nermin January 2009 (has links)
<p>Detta examensarbete handlar om finita element analys av svetsade förband i korgen på Volvo dumpern A40E. Det genomfördes i samarbete med Volvo CE i Braås. Uppgiften var att ge företaget en lämplig lösning för att minska mängden svetsskarvar på den främre delen av lastenheten. För att uppnå detta har en rad analyser genomförts med hjälp av CATIA och ANSYS på både de befintliga och de justerade (potentiella ersättare) svetsade förbanden. Analyserna visar att utmatningshållfastheten av svetsade förband huvudsakligen beror på inbränningsdjupet. Med andra ord, förstärka svetsförband genom större inbränning är mer fördelaktigt än att använda mer svets på utsidan. Slutsatsen blev att både produktionstid och kostnad kan minskas genom justering av de svetsade förbanden. Eftersom svetsförband på lastenheten är sammankopplade bör mer omfattande studier som inkluderar alla svetsar genomföras för att uppskatta effekterna av liknande justeringar.</p> / <p>The work presented in this master thesis is about the finite element analysis of the welded connections in load carrying unit of the articulated hauler, Volvo A40E. It was performed in cooperation with Volvo CE in Braås. The task was to provide the company with an appropriate solution to reduce the amount of weld used on the front part of the load carrying unit. To accomplish this, a series of analyses utilising CATIA and ANSYS was performed on both existing and adjusted (potential replacement) welded connections. The analyses brought to light the fact that the fatigue resistance of welded connections significantly depends on the penetration depth. In other words, reinforcing the welded connections by deeper penetration is more beneficial than providing support from outside through thicker weld. It was concluded that applying adjusted welds lessens both the production time and cost. Nevertheless, since the welds on the load carrying unit are correlated; more extensive studies covering all welds should be carried out to estimate the impacts of similar replacements.</p>
20

Långtidscovid: symptomförlopp och mönster över tid : En explorativ analys av crowdsource-insamlat enkätdata / Post-Acute Covid-19: Sequential Patterns and Trends in Reported Symptoms

Amundsson, Martin January 2022 (has links)
Two years after the first recorded outbreak of Covid-19 its long-term effects are still not completely understood. An unknown proportion of all covid patients go on to develop post-acute covid syndrome and suffer long-term symptoms and health effects long after the initial infection subsides. Project Crowdsourcing Långtidscovid-Sverige sent out in summer of 2021 an open online survey and gathered respondents through crowdsourcing to gather info about people in Sweden with prolonged health effects lasting at least three months after confirmed or suspected Covid-19 infection. In this thesis an explorative analysis of the aforementioned survey is conducted with its initial focus placed onthe progression of symptoms. Descriptive statistics are provided for the survey sample; hierarchical clusteringon principal components is performed; and association rule mining as well as sequence rule mining is used toextract frequently co-occurring symptoms. Women stand for 85.2% of all respondents, possibly indicating a skewed gender distribution in the sample. The average age of a respondent is 50 years old, but ranges between 18 and 80 years of age. The number of reported symptoms tend to diminish over time and symptoms within the 'air passages' category diminish on average quicker than other categories. Hierarchical clustering with Ward’s criterion revealed 4 clusters with an average silhouette coefficient of 0.246. The resulting clusters are not well-separated from each other and have some overlap in their bordering regions, and should therefore be interpreted with caution. Broadly speaking, individuals from cluster 1, 3 and 4 are distinguished primarily by their total number of symptoms reported, meanwhile cluster 2 is characterized by individuals that experience many symptoms early on and fewer symptoms later on. The most prevalent symptom over the entire period is fatigue (90.2%), closely followed by worsening symptomsafter physical activity (87.1%), problems with concentration (82.3%), headaches (79.5%), and brain fog (77.9%). There are several strong associations between various symptoms, especially for symptoms within the same category. Most symptoms have a sequential correlation with themselves and have an increased tendency to occur several times.

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