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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.
111

Model-based Controller Development

Griesebner, Klaus January 2017 (has links)
Model-based design is a powerful design technique for embedded system development. The technique enables virtual prototyping to develop and debug controllers before touching real hardware. There are many tools available covering the distinct steps of the design cycle including modeling, simulation, and implementation. Unfortunately, none of them covers all three steps. This thesis proposes a formalism coupling the model and the implementation of a controller for equation-based simulation tools. The resulting formalism translates defined controller models to platform specific code using a defined set of syntax. A case study of a line-following robot has been developed to illustrate the feasibility of the approach. The prototype has been tested and evaluated using a sequence of test scenarios of increasing difficulty. The final experiments suggest that the behaviors of both modeled and generated controllers are similar. The thesis concludes that the approach of model-implementation coupling of controllers in the simplest form is feasible for equation-based tools. This allows it to conduct the whole model-based design cycle within a single environment.
112

Nackvinkelmätningar vid thoraxoperation : Kan prismaglasögon underlätta arbetet för operationssjuksköterskor? / Neck angle measurement at Thorax operation : Can prisma glasses help the operation nurse?

Edström, Urban January 2017 (has links)
No description available.
113

Industrial Wireless IPv6 Sensor device

Borgviken, Jonathan, Johansson, Carl January 2017 (has links)
No description available.
114

Autonomous and semi-autonomous self-driving cars in Sweden : Ethical considerations

Rosenholm, Linus January 2021 (has links)
Background. Today autonomous vehicles (AV) are a well-debated topic and manystudies try to understand or solve different ethical dilemmas concerning self-driving.There are legal issues and liability concerns that require clarity from a governmentfor any type of AV to operate on the road. The Swedish transport agency has notallowed autonomous cars because they do not fulfill the requirements to be classifiedas a safe vehicle and there are only a few studies in Sweden that focus on this topic.  Objectives. This thesis will investigate previous research in this area to find outwhat are the most common topics that are a concern to people when it comes toAVs. Based on the findings from the literature review, a survey will be distributed,containing both qualitative and quantitative questions. Methods. A literature review has been performed to set up the base work for thesurvey. The questions to the survey were based on the findings from the literaturereview thereafter a pilot survey was distributed. The result from the survey will beanalysed by categorizing themes and keywords from the respondents. Results. The literature review can reveal that the most concerning categories according to people are safety, security, legal aspects & liability, and cost. The respondents to the survey indicate that safety is a high prioritized topic together with anylegal and liability aspects. The result also shows that there is a high expectationfrom the car manufacturers to make the vehicle secure from any attacks. As opposedto other research the Swedish respondents in this survey do not show much concernwhen it comes to costs.  Conclusions. A common theme from the respondents shows that safety must beprioritized before any AVs can be released on the road, with no exceptions. Many ofthe respondents show that they trust the Swedish government and its legal systemwhich indicates that the acceptance of AVs could correlate with an acceptance fromthe Swedish transport agency. Though the respondents in the survey do seem to trustin the companies ability to provide a secure vehicle there are still some concernedabout the possibility of being a victim of a cyber attack. There are no concernsabout the cost of the autonomous technology amongst the respondents but it is notevaluated why and that leaves those results open for interpretation.
115

En komparativ studie av LoRaWAN kommunikation mellan simuleringsmiljö och verklig miljö.

Skötte, Philip, Jopia Bergstedt, Calle January 2020 (has links)
IoT stands for the Internet of Things and is a concept that has been around since 1999. IoT are objects around us that collects data and connects to controls or other machines via the internet and is a field that constantly growing every year. The most used communication for IoT devices is wireless communication. The term is broad and contains many different protocols, e.g. Bluetooth, WiFi, and LoRa. LoRa, which is short for Long Range is an energy-efficient long-range wireless data transfer technology that sends small data packets between IoT nodes and LoRa receivers. A LoRa receiver can communicate with hundreds of nodes and the product has spread widely throughout the world. LoRa is the term for the physical layer for communication and LoRaWAN corresponds to the communication protocol. Simulating a LoRaWAN network is interesting as it provides an opportunity to get an idea of how it might work. This can result in increased use of network simulations in experiments and give the opportunity for companies, as well as private individuals to take the first step towards using LoRa and benefit from the results. Ns-3 is a network simulator and has been selected for use in this work. The use of a network simulator always raises questions about how credible the simulation portraits reality. With a collaboration with Etteplan, the issue for the work was formulated to: ● How well can simulation of LoRaWAN correspond to physical measurement when used between a LoRa receiver and IoT node in a free-vision environment? To answer the question, a simulation of a LoRaWAN network in the simulator Ns-3 was tested and then compared with results based on reality. The factor that was compared in the simulation against reality is the signal strength and how it is affected by spreading factors, different bandwidths and distances. The spreading factors 7 to 11 and the bandwidth 125, 250 and 500 kHz have been used at the distances 211, 1800 and 3500 meters. After analysing the data collected during the experiment it can be seen that the signal strength became stronger the higher the bandwidth used in the reality, however similar tests resulted in the simulation to the contrary. The higher bandwidth contributed to a lower signal strength. The spreading factor behaved differently in the simulation compared to the reality because it had a bigger impact on the signal strength. The conclusion of this can be that the simulation was able to integrate the signal for a longer time with higher spreading factor and this led to better signal strength as it reduced the interference of communication. However, one can conclude that the simulation showed a good picture of what a real scenario might look like between a LoRa receiver and IoT node.
116

Simulation Framework of embedded systems in armored vehicle design / Simuleringsramverk av inbyggda system i bandvagnsdesign

Bergström, Christoffer January 2021 (has links)
Embedded systems are a mixture of electric and mechanical hardware along with the software that is controlling them. BAE Systems Hägglunds, which designs and builds armored vehicles, is interested in knowing how to simulate these systems for logic validation and testing different design variations.  The goal of this thesis was to create a framework for carrying out these simulations. This was done by analyzing hardware and software design at BAE and Identifying the necessary conditions for creating a model which can be simulated.  Matlab Simulink is suggested as the tool for these simulations. The framework suggests dividing the model into smaller modules which reflects design principles at BAE. These modules will be made up of sub-modules containing hardware and software in layers. The hardware foundation will be made up of pre-designed components created in Simulink’s physical simulation library. The software will be imported into specialized sub-modules and integrated into the hardware using proposed bridge functions, converting information between the two systems. The framework is designed to provide a comprehensive solution instead of a deep one that can be adapted to changing circumstances. Tests have been made on small-scale systems, but the framework still needs to be tested on a large-scale system, which was not possible during this thesis. In conclusion, this is a stable foundation that needs to be built upon.
117

RVSingle: A general purpose power efficient RISC-V for FPGAs

Shen, YuYang January 2023 (has links)
With the increasing need for low-cost, power-efficient computing units, RISC-Vas an open-standard Instruction Set Architecture (ISA) is becoming more and more popular in the industry. There are multiple open-source RISC-V soft processors like cva6, VEGA, NOEL-V and more. But those processors have a common problem in that they can only be implemented onto a specific FPGA development platform. This thesis introduces a new processor design with compatibility in mind so that it will not be limited to a certain development platform but can be used on multiple different platforms as far as they meet the basic requirements. This processor is a single-stage processor without any pipeline implemented. The processor is used to evaluate the power efficiency of the architecture and has a unique feature to enable or disable the RISC-V Compressed (RVC) instruction subset to understand its impact on power-efficient. It is simple in architecture but still has the full capability for the RV64IC instruction set. Because of it uses RISC-V architecture, in the future, this processor can be easily expanded to adopt more RISC-V instruction subsets.
118

An implementation of an autonomous IoT system for real-time water quality monitoring with 4G and satellite connection : CatFish - Embedded systems

Elfing, Johan, Persson, Daniel January 2022 (has links)
This thesis is about implementing an Internet of Things system for measuring water quality in rivers and other aquatic environments with an autonomous water drone, where the data from various components are collected and sent wirelessly to the database in real-time. A Raspberry Pi is connected to the internet through a 4G modem and a wireless satellite communication connection called RockBlock for emergency calls and notifications. In addition, a sonar is also implemented to collect data for the unmanned surface vehicle's (USV) avoidance of collisions. Finally, batteries are connected to solar panels to auto-generate energy and provide the USV with its requested current and voltage. The minimum parameters to measure water quality are four: potential hydrogen, dissolved oxygen, nitrates, and colored dissolved organic matter. As a result, the system in this thesis measures the four parameters mentioned above, plus turbidity and temperature, since the interconnected sensors can also measure those. In addition, optical sensors were chosen because of their exceptional accuracy and precision when measuring water quality. The environment, mainly the aquatic, will benefit from this project and change for the better with time. / Den här vetenskapliga artikeln handlar om att implementera ett Internet of Things system avsett för att mäta vattenkvaliteten i floder och andra vattenmiljöer med en autonom vattendrönare, där datan från diverse komponenter samlas in och skickas trådlöst till databasen i realtid. En Raspberry Pi är ansluten till internet via ett 4G-modem samt en trådlös satellitkommunikationsanslutning som kallas RockBlock för nödmeddelanden och notifikationer. Dessutom implementeras ett ekolod för insamling av data till den autonoma vattendrönaren för undvikande avkollisioner. Slutligen är batterierna anslutna till solcellspaneler för att automatiskt generera energi och förse den autonoma vattendrönaren med tillräcklig ström samt spänning.Det minsta antalet parametrar för att mäta vattenkvalitet är fyra: potentiellt väte, löst syre, nitrat, och färgat löst organiskt material. Som ett resultat mäter systemet i denna avhandling de fyra parametrarna nämnda ovan, plusgrumlighet och temperatur, eftersom de sammankopplade sensorerna ocksåkan mäta dessa. Dessutom valdes optiska sensorer på grund av deras exceptionella noggrannhet och precision vid vattenkvalitetsmätning. Miljön, speciellt vattenmiljön, kommer att gynnas av detta projekt samt förändras till det bättre med tiden.
119

Using HLS for Acceleration of FPGA Development: A 3780-Point FFT Case Study

Hejdström, Christoffer January 2022 (has links)
Manually designing hardware for fpga implementations is time consuming. Onepossible way to accelerate the development of hardware is to use high level syn-thesis (hls) tools. Such tools synthesizes a high level model written in a languagesuch as c++ into hardware. This thesis investigates hls and the efficacy of using hls in the hardware design flow. A 3780-point fast Fourier transform optimized for area is used to compare Vitis hls with a manual hardware implementation. Different ways of writing the highlevel model used in hls and their impacts in the synthesized hardware together with other optimizations is investigated. This thesis concludes that the results from the hls implementation are not comparable with the manual implementation, they are significantly worse. Further, high level code written from a non-hardware point of view needs to be rewritten from a hardware point of view to provide good results. The use of high level synthesis is not best used by designers from an algorithm or software background, but rather another tool for hardware designers. High level synthesis can be used as an initial design tool, allowing for quick exploration of different designs andarchitectures.
120

DDoS Defense: Next-Generation Firewall versus Traditional Firewall / DDoS Defense: Next-Generation Firewall versus Traditional Firewall

Andell, William, Eskel, Filip January 2023 (has links)
Syftet med detta examensarbete var att utvärdera hur två olika brandväggar, en nästa generationens brandvägg och en traditionell brandvägg, hanterade en mindre distribuerad denial of service-attack. Enheterna kördes så nära dess förkonfiguration som möjligt. Testningengenomfördes i en kontrollerad labbmiljö på Högskolan Väst. Ett botnät bestående av 17 datorer användes och styrdes via en kommandocentral som använde IRC för att utföra attackerna. Enheterna testades med TCP- och UDP-baserade attacker under en tid av fyra minuter vardera. En dator var ansluten till det interna gränssnittet där vi kontrollerade minnet, CPU och latensen. En annan dator från botnätgränssnittet kontrollerade latensen från botnät. Resultaten visar att nästa generationens brandvägg (FortiGate40F) presterar bättre än den traditionell brandväggen (ASA 5506-X). Både Cisco ASA 5506-X och FortiGate 40F kör med 4 CPU-kärnor, där ASA 5506-X har 1250 MHz per kärna medan FortiGate 40F bara har 1200M MHz per kärna. ASA 5506-X har också 113,24% mer RAM än FortiGate. Trots att ASA 5506-X har fördelen när det gäller hårdvara, presterande FortiGate 40F bättre vid varje attack. Detta beror med stor sannolikhet på skillnaden i mjukvara hos de olika brandväggar

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