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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.
391

Development of improved determination process : Adapted for nominal setup at Volvo Car Corporation based on static, dynamic and thermal contributions / Utveckling av förbättrad bestämningsprocess : Tillämpad för nominell setup på Volvo Cars Corporation baserad på statiska, dynamiska och termiska bidrag

Andersson, William, Aune, Adrian January 2020 (has links)
A nominal setup at Volvo Cars Corporation is the placement determination for two adjacent exterior parts on the car. To place the parts in optimal positions, nominal values for gaps and flushes are determined. When a nominal setup becomes more complex, VSA (Vehicle System Architect) is summoned. These appearing situations regard the involvement of several attributes and the need for a combination of vari- ous contributions. There are static, dynamic (overslam or dynamic movement) and thermal contributions that are combined into nominal values of gap and flush dis- tances. The determination process of a nominal setup contains both calculation for each contribution, as well as the combination method which takes place at the VSA meetings. This Master Thesis project consists of the development of an improved determination process for nominal setups. The current determination process has a low level of transparency within the differ- ent group’s methods. Another issue is the insecurity of the probability estimations made when combining the contributions. Therefore, the focus of the project was to infuse a greater understanding of the contribution derivations, and greater insight into the probability of the taken risks. To achieve that, the project was divided into three parts; mapping of the determination process, individual contribution improve- ments and finally, improvements to the combination method. In contemplation of improving a process, plenty of knowledge needs to be gathered, regarding methods, simulations and possibilities. This was executed by interviewing experts within spe- cific areas at the different groups at VCC. Development of the improvements was done by interviews and various studies. It was shown that the mapping of the determination process increased the trans- parency between the groups as it increased the understanding of individual groups’ work. Contribution improvements lead to more realistic load cases used for dimen- sioning. A performed overslam clinic, where closing velocity data of a tailgate were collected, lead to a greater statistical base for which load case should be used. For dynamic movement, another method is proposed that considers relative movement instead of applied accelerations. For the thermal contribution, the approach of ge- ographically gathered temperature data was proposed. The improved combination method generates combinations with regard to three input values instead of one, from each contribution, to create different combination scenarios. The probabilities of the scenario occurrences are estimated which gave VCC a greater understanding of what risks that are taken. Furthermore, the combination method also educates the VSA meeting attendees by exhibiting the derivations and bases for each contri- bution.
392

3D YOLO: End-to-End 3D Object Detection Using Point Clouds / 3D YOLO: Objektdetektering i 3D med LiDAR-data

Al Hakim, Ezeddin January 2018 (has links)
For safe and reliable driving, it is essential that an autonomous vehicle can accurately perceive the surrounding environment. Modern sensor technologies used for perception, such as LiDAR and RADAR, deliver a large set of 3D measurement points known as a point cloud. There is a huge need to interpret the point cloud data to detect other road users, such as vehicles and pedestrians. Many research studies have proposed image-based models for 2D object detection. This thesis takes it a step further and aims to develop a LiDAR-based 3D object detection model that operates in real-time, with emphasis on autonomous driving scenarios. We propose 3D YOLO, an extension of YOLO (You Only Look Once), which is one of the fastest state-of-the-art 2D object detectors for images. The proposed model takes point cloud data as input and outputs 3D bounding boxes with class scores in real-time. Most of the existing 3D object detectors use hand-crafted features, while our model follows the end-to-end learning fashion, which removes manual feature engineering. 3D YOLO pipeline consists of two networks: (a) Feature Learning Network, an artificial neural network that transforms the input point cloud to a new feature space; (b) 3DNet, a novel convolutional neural network architecture based on YOLO that learns the shape description of the objects. Our experiments on the KITTI dataset shows that the 3D YOLO has high accuracy and outperforms the state-of-the-art LiDAR-based models in efficiency. This makes it a suitable candidate for deployment in autonomous vehicles. / För att autonoma fordon ska ha en god uppfattning av sin omgivning används moderna sensorer som LiDAR och RADAR. Dessa genererar en stor mängd 3-dimensionella datapunkter som kallas point clouds. Inom utvecklingen av autonoma fordon finns det ett stort behov av att tolka LiDAR-data samt klassificera medtrafikanter. Ett stort antal studier har gjorts om 2D-objektdetektering som analyserar bilder för att upptäcka fordon, men vi är intresserade av 3D-objektdetektering med hjälp av endast LiDAR data. Därför introducerar vi modellen 3D YOLO, som bygger på YOLO (You Only Look Once), som är en av de snabbaste state-of-the-art modellerna inom 2D-objektdetektering för bilder. 3D YOLO tar in ett point cloud och producerar 3D lådor som markerar de olika objekten samt anger objektets kategori. Vi har tränat och evaluerat modellen med den publika träningsdatan KITTI. Våra resultat visar att 3D YOLO är snabbare än dagens state-of-the-art LiDAR-baserade modeller med en hög träffsäkerhet. Detta gör den till en god kandidat för kunna användas av autonoma fordon.
393

Affärsmodellsinnovation för använda elbilsbatterier : En studie kring hinder, utmaningar och möjliga utfall av implementering av affärsmodellsinnovation för återanvändning av elbilsbatterier

Alizade, Ali, Khoshnaw, Diar January 2023 (has links)
Detta examensarbete är tillägnad att undersöka hur affärsmodellsinnovation kan skapa förutsättningar för att underlätta återanvändandet av elbilsbatterier samt analysering av möjliga värdeskapande utfall. Arbetet fokuserar på att samla data från större aktörer som hanterar begagnade elbilsbatterier. Kartläggning av deras affärsmodeller genom kvalitativa intervjuer ger läsaren och författarna en större inblick kring hur cirkulära affärsmodeller fungerar och vart de behöver innovation.  Elbilar har det senaste decenniet en större andel av nybilsförsäljningen och med direktiv från både EU och den svenska staten, kommer det ebdast vara möjligt att köpa eldrivna samt vissa gasdrivna fordon från 2035. Detta medför en större batteriproduktion vilket även leder till en större grad av exploatering av nuvarande litium- och molybden reserver. Dessa reserver kommer att räcka i ca 70 år om inte nya tillgångar upptäcks och större fokus på att kunna återanvända blir aktuellt.  Denna omfattande gröna omställning av bilindustrin sätter även press på batteri producenter till en mer hållbar tillverkning som tar hänsyn till behovet av att kunna återvinna/återanvända. Denna eftertraktade designförslag är däremot något nytt hos många producenter och resterande verkar inte kunna nå en optimal grad av återvinningsberhet. Kvar blir alternativet att kunna återanvända batterierna från den befintliga elbilsmarknaden. Denna studie inspireras av cirkulär ekonomi och cirkulära affärsmodeller som kan effektivt handskas med problemen dem begagnade elbilsbatterierna för med sig. Studiens forskningsfrågor grundar sig först och främst hur befintliga affärsmodeller ser ut, vad för innovation det krävs samt hur denna innovation kan skapa förutsättningar för återanvändning.  Kartlägning av affärsmodeller från större återanvändning/återvinnings aktörer såsom Northvolts dotterföretag Revolt samt Stena Recycling, BatteryLoop, visar på ett behov av en mer intergrerad spårning och distrubering av själva elbilsbatterierna. Studien visar att affärsmodellsinnovation behövs inom uppsamling av begagande elbilsbatterier där en digital plattform möjliggör interaktion mellan köpare och säljare. Dessutom kontrolleras varje begagnat batteri innan den når marknaden vilket skapar fler förutsättningar för cirkularitet och främjar återvinning. / This thesis is dedicated to investigating how business model innovation can create the conditions to facilitate the reuse of electric car batteries as well as analyzing possible value-creating outcomes. The work focuses on gathering data from major players who handle used electric car batteries. Mapping their business models through qualitative interviews gives the reader and the authors a greater insight into how circular business models work.  In the last decade, electric cars have taken larger share of the new car sale och with directives from both the EU and the Swedish state, it will only be possible to buy electric-powered abd sin gas-powered vehicles from 2035. This entails a greater battery production, which also leads to a greater degree of exploitation of current lithium and molybdenum reserves. These reserves will last for about 70 years unless new assets are discovered and a greater focus on being able to reuse and recycle becomes relevant.  This comprehensive green transformation of the car industry also puts pressure on battery producers to a more sustainable production that considers the need to be able to be recycled/reused.However, this sought-after design proposal is something new for many producers and the rest do not seem to be able to reach an optimal degree of recyclability. What remains is the option of being able to reuse the batteriers from the existing electric car market. This study is inspired by circular economy and circular business models that can effectively deal with the problems that used electric car batteries bring with them. The study's resarch questions are first and foremost based on what existing business models look like, what kind of innovation is required and how this innovation can create conditions for reuse. Mapping of business models from major reuse/recycling actors such as North Volts's subsidiary Revolt and Stena Recycling, Battery Loop, shows a need for more intergrated tracking and distribution of the electric car batteriers themselves.  This study shows that business model innovation is needed in the collection of used electric car batteries where a digital plattform enables interaction between buyers and sellers. In addition, every used battery is checked before it reaches the market, which creates more conditions for circularity and promotes recycling.
394

Vem eller vad kan hållas straffrättsligt ansvarig för ett självkörande fordon? : En analys av gällande rätt och föreslagen lagstiftning i Sverige / Who or what can be held criminally liable for an automated vehicle? : An analysis of current law and proposed legislation in Sweden

Dahlström, Petri January 2023 (has links)
The last decade has seen a rapid advancement in the fields of artificial intelligence (AI) and automation, with terms such as machine learning, deep learning and algorithms finding their way into everyday conversations. The usage of AI is evergrowing and present in many areas of life such as health care, financial services, and social media interactions. One subject which has garnered a significant amount of attention is the introduction of autonomous vehicles (AVs) and their promise of a safer and more efficient global traffic environment. However, while self-driving technology is developing at an exponential rate, associated laws and regulations are falling behind. The legal issues connected to AVs tend to differ from one jurisdiction to another, but a concern shared among most is the uncertain state of the legal landscape with respect to criminal liability. This study is focused on critically evaluating this uncertain legal landscape from a Swedish perspective. The method used in this thesis is a blend of legal dogmatics and legal analytics. A specific branch of legal analytics, legal informatics, is largely applied due to its suitability in analyzing the relationship between law and information technology. After a brief introduction to AI and AVs, the investigation begins by examining current law to determine how a general implementation of AVs would be handled by existing regulation. The thesis then continues to analyze the potential effects of the European proposal of an electronic legal personhood for AI and its associated ethical considerations. Lastly, the paper explores the Swedish proposal for a specialized AV regulation in comparison to current Swedish and international law. The conclusion of this study is that certain traffic scenarios tend to make the criminal liability assessment clearer than others. A human driver will generally not be held responsible if a vehicle driven by an automated driving system causes an incident. In most cases, the liability will be attributed to the vehicle’s owner or manufacturer. The most interesting and complex situations involve AVs with a lower level of autonomy. These vehicles require human assistance and oversight, leading to intricate questions about culpability and causality. However, the lack of existing specialized law and the unsettled nature of the proposed regulation means that any conclusions drawn regarding criminal liability and AVs are, to some extent, uncertain and hypothetical, emphasizing the need of a globally harmonized legal landscape.
395

Heat Release Studies by pure Rotational Coherent Anti-Stokes Raman Scattering Spectroscopy in Plasma Assisted Combustion Systems excited by nanosecond Discharges

Sheehe, Suzanne Marie Lanier 14 November 2014 (has links)
No description available.
396

Svenskarnas syn på självkörande bilar och dess etiska och moraliska konsekvenser / Sweden's view of self-driving cars and their ethical and moral consequences

Abrahamsson, Alexander, Arvidsson, Wictor January 2023 (has links)
Artificiell intelligens är ett fenomen som bara blir större och större i världen och i Sverige. Teknologin börjar bli allt vanligare för att bilar ska kunna köra sig själva, med andra ord självkörande bilar. I dagsläget har Sverige ingen lagstiftning för helt självkörande bilar i Sverige. Genom en kvantitativ undersökning har allmänhetens inställning och godkännande av fenomenet i Sverige undersökts. Vidare har studien undersökt vem den svenska befolkningen anser borde stå till svars i bilolyckor med självkörande bilar. Författarna kunde konstatera att lagstiftningen ligger efter tekniken och för att de helt självstyrande bilarna ska kunna implementeras i Sverige borde det ske en förändring i lagstiftningen för att bemöta den allmänna uppfattningen kring självkörande bilar i Sverige. Studiens resultat kom fram till att en ändring av den gällande lagstiftningen borde bli aktuell där lagen gynnar människor samt företagen bakom tekniken, inte bara som det är nu att lagen enbart gynnar biltillverkarna då de inte har något ansvar vid bilolyckor med halvt självkörande bilar. För att människor ska känna tillit till tekniken behövs det en större kunskap kring fenomenet. Detta skulle biltillverkarna kunna fixa genom att låta användaren av bilen ha en större vetskap över till exempel den data som företagen samlar in samt vad den används till. / Artificial intelligence is a phenomenon that is only getting bigger and bigger in the world and in Sweden. The technology is becoming increasingly common for cars to be able to drive themselves, in other words self-driving cars. Sweden currently has no legislation for fully self-driving cars in Sweden. Through a quantitative survey, the public's attitude and acceptance of the phenomenon in Sweden has been examined. Furthermore, the study investigated who the Swedish population believes should be held accountable in car accidents with self-driving cars. The authors were able to state that the legislation lags behind the technology and in order for fully self-driving cars to be implemented in Sweden, there should be a change in the legislation to meet the general perception of self-driving cars in Sweden. The results of the study came to the conclusion that a change in the current legislation should be relevant where the law benefits people as well as the companies behind the technology, not just as it is now that the law only benefits the car manufacturers as they have no responsibility in car accidents with semi-autonomous cars. In order for people to trust the technology, a greater knowledge of the phenomenon is needed. The car manufacturers could fix this by letting the user of the car have greater knowledge of, for example, the data that the companies collect and what it is used for.
397

From Chaos to Cohesion, Identifying Inter-team Dependencies in Large-scale Agile Organisations : A case study of Volvo Cars / Från kaos till samarbete, Identifiering av beroenden mellan team i storskaliga agila organisationer : En fallstudie av Volvo Cars

Källström, Anton, Westerberg, Johan January 2023 (has links)
Product development is more complex than ever. Industries all over the world face intensified competition, forcing firms to improve their innovation performance. This involves integrating software development to a greater extent. As an effort to cope with such progression, agile project management methodologies have been adopted. These include methodologies that are tailored to fit large organisations, made to enhance communication and speed up decision-making. Moreover, such methodologies allocate time for joint planning sessions (such as Program Increment Planning) to foster coordination between teams. The need for extensive coordinating capabilities increases with firm size and product complexity, meaning that large, multinational manufacturers with integrated software- and hardware development face the greatest challenges. With difficult coordination challenges comes a demand for prominent organisational coordination capabilities. This includes capabilities to identify dependencies between agile teams in time, to avoid delays, budget overruns, and quality issues. Hence, firms must adopt sufficient project management procedures, as well as shape organisational artefacts, processes, and culture to maximise their organisational coordination capabilities. In this project, these artefacts, processes, and the organisational culture were defined as factors. Furthermore, the project aimed at (1) – identifying factors that positively contribute to organisations’ capabilities to find inter-team dependencies, and (2) – investigating how to favour those identified factors. The research was conducted at Volvo Car Corporation, a Swedish car manufacturer that undergoes a transition towards being a large-scale agile organisation. Theories concerning coordination, communication, and knowledge management were jointly deployed to construct a state-of-the-art theoretical framework. Thereafter, the conceptual model was the guiding lens for collecting and analysing empirical evidence. Consequently, this project was able to assess 26 factors for identifying inter-team dependencies. Furthermore, several of these factors are proven to be interconnected as they fuel each other and exist in symbiosis. Thus, this project advocates that large-scale agile organisations must understand these factors and their connection to each other — that is when incorporating coordination mechanisms to better identify inter-team dependencies.
398

Generating Procedural Environments using Masks : Layered Image Document to Real-time environment

Eldstål, Emil January 2019 (has links)
This paper will explore the possibilities of using an automated self-made procedural tool to create real-time environments based on simple image masks. The purpose of this is to enable a concept artist or level designer to quickly get out results in a game engine and to be able to explore ideas. The goal of this thesis was to better understand how you can break down simple ideas and shapes into more complex details and assets. In the first part of this thesis, I go over the traditional workflow of creating a real-time environment. I then go on and break down my tool, what it does and how it works. I start off with a Photoshop file, make tools in Houdini and then utilize those in Unreal for the end result. I also argument about the time-saving possibilities with these tools. From the work, I draw the conclusion that these kinds of tools save a lot of time for repeating tasks and the creation of similar environments.
399

Dynamic modeling and feedback control with mode-shifting of a two-mode electrically variable transmission

Katariya, Ashish Santosh 31 August 2012 (has links)
This thesis develops dynamic models for the two-mode FWD EVT, develops a control system based on those models that is capable of meeting driver torque demands and performing synchronous mode shifts between different EVT modes while also accommodating preferred engine operating points. The two-input two-output transmission controller proposed herein incorporates motor-generator dynamics, is based on a general state-space integral control structure, and has feedback gains determined using linear quadratic regulator (LQR) optimization. Dynamic modeling of the vehicle is categorized as dynamic modeling of the mechanical and electrical subsystems where the mechanical subsystem consists of the planetary gear sets, the transmission and the engine whereas the electrical subsystem consists of the motor-generator units and the battery pack. A discussion of load torque is also considered as part of the mechanical subsystem. With the help of these derived dynamic models, a distinction is made between dynamic output torque and steady-state output torque. The overall control system consisting of multiple subsystems such as the human driver, power management unit (PMU), friction brakes, combustion engine, transmission control unit (TCU) and motor-generator units is designed. The logic for synchronous mode shifts between different EVT modes is also detailed as part of the control system design. Finally, the thesis presents results for responses in individual operating modes, EVT mode shifting and a full UDDS drive cycle simulation.
400

Ultrafast Raman Loss Spectroscopy (URLS) : Understanding Resonant Excitation Response And Linewidth Changes

Adithya Lakshmanna, Y 11 1900 (has links) (PDF)
Raman spectroscopy involves change in the polarizability of the molecular system on excitation and is based on scattering process. Spontaneous Raman scattering is a two photon process, in which the input light initiates the excitation, which then leads to an emission of another photon due to scattering. It is extensively used to understand molecular properties. As spontaneous Raman scattering is a weak process, the detection of these weak Raman photons are rather difficult. Alternatively, resonance Raman (RR) scattering is another technique where the excitation wavelength is chosen according to the material under study. The excitation wavelength is chosen to be within the absorption spectrum of the material under study. RR spectroscopy not only provides considerable improvement in the intensity of the Raman signal, but also provides mode specific information i.e. the modes which are Franck-Condon active in that transition can be observed. There are reports on RR studies of many systems using pulsed light as an excitation source. It is necessary to use at least two pulsed laser sources for carrying out the time resolved RR spectroscopy. A single pulse source for excitation would lead to compromise either with temporal or spectral resolution which is due to the uncertainty principle. If an excitation pulse has pulse width of ~100 femtoseconds then the spectral resolution will be ~ 150 cm-1. It is clear now that for improving the temporal and spectral resolution simultaneously, usage of single pulse for Raman experiments (spontaneous scattering) is not adequate. The usage of multiple laser pulses may provide the way out to improve the resolutions. Nonlinear spectroscopy in a broad view helps in understanding the structural and dynamical properties of the molecular systems in a deeper manner. There are a number of techniques as a part of nonlinear spectroscopy that have emerged in due course to meet different requirements and to overcome some difficulties while understanding the molecular properties. Stimulated Raman (SRS) gain, coherent anti-Stokes Raman scattering (CARS) and the inverse Raman spectroscopy are a few to mention as third order nonlinear spectroscopic techniques which give the similar kind of information about the molecular systems. Stimulated Raman scattering is a more general process involved in nonlinear Raman processes. SRS involves at least two laser pulses and the difference in their frequencies should match with the vibrational frequency of the molecule. The polarization has to be matched between the Raman pump and the Raman probe pulses. We have developed a new nonlinear Raman technique in our laboratory named as ultrafast Raman loss spectroscopy (URLS) using the principles of nonlinear Raman scattering. It involves the Raman pump (~ 1 picosecond (ps) or ~ 15 cm-1spectral resolution) and Raman probe as a white light continuum (100 fs) whose frequency components ranges from 400-900 nm. The laser system consists of Tsunami which is pumped by a Millennia laser and Spitfire-Pro, a regenerative amplifier which is pumped by an Empower laser. Tsunami provides a 100 fs, 780 nm centered, 80 MHz and ~6 nJ energy laser pulses. The Tsunami output is fed into Spitfire to amplify its energy and change the repetition rate to 1 KHz. The pulse length of the input pulse is preserved in amplification. The output of amplifier is split into two equal parts; one part is used to pump the Optical Parametric Amplifier (OPA) in order to generate wavelengths in the range 480-800 nm. The output of the OPA is utilized to generate Raman pump which has to be in ps in order to get the best spectral resolution. A small portion of the other part of amplifier output is utilized to generate white light source for the Raman probe. The remaining part of the amplifier output is used to pump TOPAS to generate wavelengths in the ultraviolet region. URLS has been applied to many molecular systems which range from non-fluorescent to highly fluorescent. URLS has been demonstrated to be very sensitive and useful while dealing with highly fluorescent systems. URLS is a unique technique due to its high sensitivity and the Raman loss signal intensity is at least 1.5-2 times higher as compared to the Raman gain signal intensities. Cresyl violet perchlorate (CVP) is a highly fluorescent system. URLS has been applied to study CVP even at resonance excitation. Rhodamine B has also been studied using URLS. Spontaneous Raman scattering is very difficult to observe experimentally in such high quantum yield fluorescent systems. The variation in the lineshapes of the Raman bands for different RP excitation wavelengths in URLS spectra shows the mode dependent behavior of the absorption spectrum. The experimental observation of variation in the lineshape has been accounted using theoretical formalism. The thesis is focused on discussing the development of the new nonlinear Raman spectroscopic technique URLS in detail and its applicability to molecular systems for better understanding. A theoretical formalism for accounting the uniqueness of URLS among the other nonlinear Raman techniques is developed and discussed in various pictorial representations i.e. ladder, Feynman and closed loop diagrams. A brief overview of nonlinear spectroscopy and nonlinear Raman spectroscopy is presented for demonstrating the difference between the URLS and the other nonlinear Raman techniques.

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