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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.
461

Prediction models for soccer sports analytics

Nsolo, Edward January 2018 (has links)
In recent times there has been a substantial increase in research interest of soccer due to an increase of availability of soccer statistics data. With the help of data provider firms, access to historical soccer data becomes more simple and as a result data scientists started researching in the field. In this thesis, we develop prediction models that could be applied by data scientists and other soccer stakeholders. As a case study, we run several machine learning algorithms on historical data from five major European leagues and make a comparison. The study is built upon the idea of investigating different approaches that could be used to simplify the models while maintaining the correctness and the robustness of the models. Such approaches include feature selection and conversion of regression prediction problems to binary classification problems. Furthermore, a literature review study did not reveal research attempts about the use of a generalization of binary classification predictions that applies different target class upper boundaries other than 50% frequency binning. Thus, this thesis investigated the effects of such generalization against simplicity and performance of such models. We aimed to extend the traditional discretization of classes with equal frequency binning function which is standard for converting regression problems into the binary classification in many applications. Furthermore, we ought to establish important players’ features in individual leagues that could help team managers to have cost-efficient transferring strategies. The approach of selecting those features was achieved successfully by the application of wrapper and filter algorithms. Both methods turned out to be useful algorithms as the time taken to build the models was minimal, and the models were able to make good predictions. Furthermore, we noticed different features matter for different leagues. Therefore, in accessing the performance of players, such consideration should be kept in mind. Different machine learning algorithms were found to behave differently under different conditions. How-ever, Naïve Bayes was determined to be the best-fit in most cases. Moreover, the results suggest that it is possible to generalize binary classification problems and maintain the performance to a reasonable extent. But, it should be observed that the early stages of generalization of binary classification models involve a tedious work of training datasets, and that fact should be a tradeoff when thinking to use this approach.
462

Project Sunlight

Karlsson, Niklas, Johansson, Thim January 2020 (has links)
No description available.
463

Modular Battery Management System interface to integrated Vehicle Control Unit : Creating a BMS playground using Arduino

André, Joel January 2020 (has links)
Development today has moved more towards battery technology, partly due to the increased demand of electric vehicles (EVs). The quest for a sustainable society is at an all-time high, with electrification of almost all devices only being the beginning. Due to the use of the fragile Lithium-Ion battery, a system that controls and monitors the battery must be implemented to ensure that it operates normally. A system like this is often referred to as a Battery Management System (BMS), in this case for Lithium-Ion batteries. The objective in this thesis is to construct a modular BMS playground for NEVS in Trollhättan to continue development on. The interface for the system will consist of Controller Area Network (CAN), a fast and robust communication protocol used in almost all personal vehicles today, and Isolated Serial Peripheral Interface (isoSPI), an isolated adaptation of one of the most common communication protocols used in sensors and microcontrollers so far. The BMS will be constructed of four individual subsystems using Arduino, each with a different purpose. These four subsystems are later merged into one BMS system to offer communication between CAN and isoSPI, thus supporting a future integration of this BMS to the Vehicle Control Unit of an EV. Moreover, since the BMS is going to be developed for a vehicle, modes for engaging the vehicle to drive and stop will be made. In order to provide some safety measures, automatic disconnection of the battery in case of an error will be added. The BMS with the previously mentioned features, also capable of doing voltage measurements with a safe connection/disconnection of the battery was then made. Features such as current and temperature monitoring were omitted due to time constraints and will in the future instead be done by NEVS along additional features. This thesis was conducted by Karlstad University and NEVS in Trollhättan, Sweden.
464

NON-CONTACT PCB FAULT DETECTION USING NEAR FIELD MEASUREMENTS AND THERMAL SIGNATURES

Bengtsson, Daniel, Löw, Wicktor January 2020 (has links)
No description available.
465

Design of a Simulation Startup Model for a Marine Current Turbine

Carlénius, Isak, Johansson, Valle January 2020 (has links)
This project is aimed at developing a simulation model in Simulink for a new startup system controlling the marine current turbine at Uppsala university's research facility in Söderfors. The goal is to design a circuit that is able to switch between feeding power to and extracting power from the synchronous machine in order to control the rotational speed of the turbine. The technical solution consisted of two separate circuits combined into the final system. First, the synchronous machine is run as a BLDC motor where power is fed to the motor in order to accelerate the turbine. Then, at a specified rotational speed threshold the BLDC circuit is disconnected and the turbine continues to accelerate by picking up power from the water alone. Lastly, when the rotational speed reaches the desired setpoint for the rotational speed the synchronous machine is connected to a DC load. By controlling the power extracted in the load with a PI controller the rotational speed of the turbine stays at the setpoint value. Results from the simulation model shows that it is possible to control the startup process of the turbine with such a system. In future projects improvements can be made regarding removing current spikes, more smooth power usage and faster PI controllers. To further develop the startup system the next step would be to translate the simulation model into LabVIEW code in order to test it at the site in Söderfors.
466

Study of Student Electricity Use in Uppsala

Torbjörner, Max, Gundstedt, Anthony, Shaposhnikov, Philip January 2020 (has links)
This report covers a project that set out to create our own and implement another existing measurement system that measures the power consumption in different student residences with higher resolution then what is currently offered by Vattenfall. This is important since there is a problem in Uppsala with a lack of power from the electrical grid which limits Uppsalas ability to grow as a city. Different dorm rooms in the housing area Gamla Studenstaden were then measured and data with the resolution of 1 minute was then analysed. This data was then used in order to answer which type of accommodation is most efficient with its power usage in relation to the amount of rooms. This report also wanted to answer how different types of accommodations cause spikes in their power usage which are only possible to spot with the higher resolution. The resulting data show that one-room apartments has relatively low power consumption over the day but contribute to so called power spikes which cause large load on the power grid. The dorm rooms did however seem to have a more distributed power consumption over the day.
467

Usage of two-way radio transceivers in industrial environment

David, Nyman January 2020 (has links)
No description available.
468

Smart shading regulated by the time at specific voltage

Al-hadi, Mahmood January 2020 (has links)
No description available.
469

Design of Thermal Control System for the Spacecraft MIST

Berggren, Andreas January 2015 (has links)
In 2014 KTH Royal Institute of Technology initiated a space technology and research center, KTH Space Centre. MIST (MIniature Student saTellite) is the rst student project conducted at KTH Space Centre and also the rst student satellite from KTH with a predicted launch in 2017. This report includes the thermal analysis and control of the spacecraft MIST. One of the main systems in a spacecraft is the thermal control system. In order for the payloads and subsystems to withstand the harsh thermal environment in space a thorough thermal analysis is needed. In this project the thermal model has been built and thermal control design of the spacecraft has been started. As a start a preliminary thermal analysis was performed where the spacecraft was approximated as a sphere in order to get some estimates on the temperature in orbit due to the space environment. Furthermore the temperature decrease in eclipse was studied. Since most of the spacecraft will consist of Printed Circuit Boards (PCB) the thermal behavior of PCB has been investigated and as a part of this investigation a thermal vaccum chamber test was performed where the conductance from a PCB through the mounting interface to a metal plate was measured. This report will also guide the reader through the model built and assumptions made. As a part of the thermal control, Multi Layer Insulation (MLI) has been studied and modeled in two di erent ways which have been compared with each other in order to know the level of detail needed for the MLI model. Last but not least the design of the thermal control system has been started where some payloads have been wrapped in MLI and thermal contact conductance coecient has been changed in order to meet the thermal requirements of the payloads and subsystems.
470

Transformer test bench -implementation and usability

Ayddan, Jonas, Özbek, Emin January 2015 (has links)
The task of this master's thesis was to design a transformer test bench while focusing on safety and usability. There are several safety risks when working with high voltages, therefore the high demand for safety precautions. A bench was worked upon, and attachments, such as module frames and banana connectors were integrated into the bench. Further, a list of components were modied and installed on the new bench. A new design, using a magnetic non-contact safety interlock switch and an easy-to-apply circuitry, was proposed and implemented. In addition to the implementation, a code in LabVIEW was written in order to handle the measured data from the tests that can be performed on a transformer. Several tests were performed on a single-phase transformer and a three-phase transformer in order to verify the function of the transformer test bench, with respect to the design. Complications emerged due to random additive noise. After some work, the noise was suppressed and the results showed that the equipment worked well with the new design. Finally, a user's manual was written in order to guide the user through the wire connections, tests and the developed software in LabVIEW. / En transformatortestbänk avsedd för laborationer inom forskning och utbildning har utvecklats, där fokus har lagts på säkerhet och användbarhet, eftersom arbete med höga spänningar medför säkerhetsrisker. En bänk modierades för att möjliggöra fastsättning av moduler samt banankontakter. Vidare anskaades elektroniska komponenter, bearbetades och installerades. En design med en magnetisk switch samt lättanvända kretsar föreslogs. Dessutom skrevs en kod i LabVIEW med ett brett användningsområde. Ett  flertal tester utfördes på en enfastransformator och en trefastransformator med syfte att säkerställa att komponenter- na fungerar väl ihop med den framtagna transformatortestbänken. En del komplikationer uppstod på grund av slumpmässigt, additivt brus. Detta gick dock att undertrycka. Det slutliga resultatet visade att kom- ponenterna fungerade väl ihop med den framtagna transformatortestbänken. Slutligen skrevs en användarmanual med syfte att instruera använda- re av transformatortestbänken beträande kopplingarna, testerna samt mjukvaran som är skriven i LabVIEW.

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