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Carbon capture and storage (CCS) is a method to reduce the emission of CO2 into the atmosphere. Stockholm Exergi is a Stockholm based company with combined heat and power (CHP) plants in various places around the city and are currently investigating the possibilities to implement CCS on their CHP plant Högdalenverket. The captured CO2 is required to be transferred from the facility to a harbour for further transport to its injection site. This report investigates the optimal means of transportation from the facility to harbour. The methods considered are pipeline and trucks.From the frame of reference, it is concluded that the shortest distance possible is preferable, so the harbour alternative is set to be Värtan. For pipelines the cheapest alternative of the state of form, for the specific case, is gas. For trucks the best alternative is liquid since a larger amount can fit in each load. For the cost estimation the method from (Piessenset al., 2008) is used to calculate the price estimate of pipelines, and (Marufuzzaman, 2015) is used for the trucks. Parameters such as the diameter of the pipe, pressure drop and power requirement are of high importance for the pipeline. For truck road regulations, CO2’s density and operation time is essential. The results from the implementation shows the pipelines to be the more beneficial option in regards to price, stability and robustness. The NPV for the pipeline is calculated, with the lifetime of theproject as 25 years, to be 75 million €, which is the cheaper alternative compared to the truck, which has a NPV of 95 million €. The optimal inlet pressure for the pipes is calculated to be 3.5MPa and the temperature to be 57.5°C due to an implemented heat exchange operation before the inlet. Future work and recommendations are to continue creating a more detailed design over the pipelines and to discard the truck transport alternative. / Infångning och lagring av koldioxid (CCS) är en metod för att minska utsläppen av CO2 i atmosfären. Stockholm Exergi är ett energibolag i Stockholm med diverse kraftvärmeverk runtom i staden. En undersökning pågår där företaget forskar kring möjligheterna att implementera CCS på kraftvärmeverk Högdalenverket. Den uppfångade koldioxiden ska transporteras från anläggning till hamn, där den sedan ska vidare med skepp till sin injektionsplats. Denna rapport studerar vilken den optimala metoden för transport från anläggning till hamn är. Metoderna som berörs är rörledningar och lastbilar. Från bakgrundstudien var det möjligt att dra slutsatsen om att det kortaste möjliga avståndet är optimalt, så den valda hamnen är Värtahamnen. För rörledningarna är det billigaste alternativet på substansen gas för det behandlade fallet i rapporten. För lastbilsalternativet är den optimala formen vätska då det får plats mer volym per last. För uppskattningen av priserna används metoden från (Piessenset al., 2008) för rörledningarna och (Marufuzzaman, 2015) för lastbilarna. Parametrar såsom diametern på rören, tryckfall och effektkrav är viktiga för rörledningarna. För lastbilarna är vägkrav, CO2 s densitet och operationstid essentiella. Resultaten från implementationen visar att transport med rörledningar är det optimala alternativet i avseende av pris och stabilitet. Nuvärdet på investeringen av rörledningarna är beräknade till 75miljoner €, som är billigare jämfört med 95 miljoner € för lastbilsalternativet. Det optimala trycket för inloppet till rörledningarna är beräknat till 3.5 MPa och inloppstemperaturen till 57.5°C som resultat av en implementerad värmeväxlaroperation precis före starten på rörledningen. Framtida arbete och rekommendationer är att fortsätta utveckla en mer detaljerad design överrörledningen och att avfärda alternativet med transport av lastbilar.

For internal combustion engines used in heavy-duty vehicles, increased engine efficiency and consequently reduced CO2 emissions can be obtained if the engine speed can be kept within an optimal speed range. This requires swift and frequent gear shifts where the dry friction clutch is utilized. Enhanced dry clutch simulation models and a better understanding of the involved phenomena can assist the development towards swifter gear shifts and help reduce CO2 emissions. The work presented in this thesis focuses on the modelling of dry clutch systems for heavy-duty applications and their effect on the torsional response of the driveline during transient events such as clutch engagement and disengagement. During these events it is primarily the first vibration mode of the driveline that is active and consequently it is possible to greatly reduce theof degrees of freedom (DOFs) of the powertrain model and still capture the relevant dynamics of the powertrain. The reduced set of differential equationsdescribe the torsional motion of the powertrain and the equations of motion are solved numerically in the time-domain. From a mathematical point ofview, the equations of motion turn "stiff" when the clutch is locked. This issue is resolved by utilizing numerical solution techniques suitable for stiff differential equations. In the simulations it was observed that no engine torque fluctuations were transferred through the slipping clutch. Consequently the response of the driveline is purely modal during sliding. If the gradient of the coefficient of friction is negative the modal response is possibly unstable with exponentially growing vibration amplitudes as an effect. Moreover, the way in which the clamp load evolves during clutch engagement is found to severely effect the excitation of transient vibrations during clutch synchronization. It can be shown that reducing the gradient of the evolving clamp load at the onset of sliding will reduce the amplitude of the friction induced vibrations. Reducing the torsional vibration amplitudes will help avoid the jerky motion of the vehicle during launch and increase comfort for driver and passengers. / Reduced transmission vibrations - reduced energy consumption and environmental impacts together with an increased competitiveness. Swedish Energy Agency (project No. 42100-1)

The application of stochastic modeling for learning the behavior of multibody dynamics models is investigated. The stochastic modeling technique is also known as Kriging or random function approach. Post-processing data from a simulation run is used to train the stochastic model that estimates the relationship between model inputs, such as the suspension relative displacement and velocity, and the output, for example, sum of suspension forces. Computational efficiency of Multibody Dynamics (MBD) models can be improved by replacing their computationally-intensive subsystems with stochastic predictions. The stochastic modeling technique is able to learn the behavior of a physical system and integrate its behavior in MBS models, resulting in improved real-time simulations and reduced computational effort in models with repeated substructures (for example, modeling a train with a large number of rail vehicles). Since the sampling plan greatly influences the overall accuracy and efficiency of the stochastic predictions, various sampling plans are investigated, and a space-filling Latin Hypercube sampling plan based on the traveling salesman problem (TPS) is suggested for efficiently representing the entire parameter space. The simulation results confirm the expected increased modeling efficiency, although further research is needed for improving the accuracy of the predictions. The prediction accuracy is expected to improve through employing a sampling strategy that considers the discrete nature of the training data and uses infill criteria that considers the shape of the output function and detects sample spaces with high prediction errors. It is recommended that future efforts consider quantifying the computation efficiency of the proposed learning behavior by overcoming the inefficiencies associated with transferring data between multiple software packages, which proved to be a limiting factor in this study. These limitations can be overcome by using the user subroutine functionality of SIMPACK and adding the stochastic modeling technique to its force library. / Ph. D.

yes / Literature on truck pushers stereotype these boys as social misfits, criminals and nuisance to society; often regarded as creating streetism. Much consideration has not been given to their contribution to the economy as well as what motivates these boys to go into truck pushing. This chapter outlines research with 30 (20 current and 10 former) truck pushers, 5 customers who patronised the services of the truck pushers were interviewed for their views on the services of the truck pushers. Finally, 5 kayayei (female head porters) at the market were interviewed to find out if the presence of kayayei in the market has affected the business of the truck pushers. The study found that the services provided by truck pushers especially to petty traders and other shoppers were indispensable because they provide cheap, readily available and customised service. Due to poor urban planning and deplorable road networks in Ghana, many areas are not accessible by motorised transport, hand pushed trucks have become the most useful and efficient means of transporting goods from the markets to bus terminals and on some occasions to customers’ homes and shops. The chapter argues that non-motorised transport to the informal sector cannot be overemphasised; therefore truck pushers should be seen as bridging a gap in urban transportation, instead of the social misfit label attached to them.

Weigh-in-Motion (WIM) systems have improved the process of collecting data from heavy vehicles on the U.S. highway system and enforcing the laws that govern vehicle weights. The benefits of WIM are reaped by everyone from highway designers and voernments officials, to truck drivers and transportation industry owners. The data collected by WIM devices is essential for proper pavement design, developing pavement management systems, weight enforcement strategies, modeling traffic improvement projects, and predicting load-related distresses and performance. While WIM offers many advantages over its alternative, static weighing, the technology is limited by problems associated with the accuracy of its measurements. Weigh-in-Motion systems that lack accuracy require vehicles to travel slower and can result in higher queues, longer delays, and potential hazards. For these reasons, WIM system performance must be improved in order to adequately serve its purpose. In order to evaluate WIM system performance and determine what vehicle characteristics have the most affect on it, two systems in the Commonwealth of Virginia were evaluated. The first system was an in-service WIM system at the Troutsville weigh station on I-81. The Troutsville station had bending plate WIM scales located in both the northbound and southbound directions. The second system in a newly developed WIM system manufactured by Omni Weight Corporation (OWC) and was installed at the Virginia Smart Road for evaluation. The OWC scale is a completely sealed and buried system that has ten strain gauge sensors in its interior. Evaluation of both scales was performed by conducting a number of test runs under varying load conditions. Testing at Troutsville was performed using four different test vehicles with multiple loads on each. Variation in load was achieved by loading the test vehicles with various numbers of concrete Jersey Walls. Testing on the OWC scale was performed using only two test vehicles while varying the speed, load, tire pressure, and direction of travel over the scale. The study showed that the scales at the Troutsville weigh station yielded 10% error or less on only 77% of the tests, not complying with the required 95% set forth by ASTM E-1318. In comparison, using the manufacturer's processed data for the OWC scale yielded only 18% of its tests with 10% error or less, far below the ASTM standard. A model was developed to re-calculate the axle weights using the raw sensor data from the OWC scale; and an evaluation of the accuracy of this data showed that the OWC scale performed much better. While compliance with the ASTM standards was still not achieved, it rose from 18% to 71% of the tests having 10% error or less. Repeatability of the Troutsville scales and OWC scales was found to be comparable. / Master of Science