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  • 51.
    Grahn, Erik
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Evaluation of MEMS accelerometer and gyroscope for orientation tracking nutrunner functionality2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the production industry, quality control is of importance. Even though today's tools provide a lot of functionality and safety to help the operators in their job, the operators still is responsible for the final quality of the parts. Today the nutrunners manufactured by Atlas Copco use their driver to detect the tightening angle. There- fore the operator can influence the tightening by turning the tool clockwise or counterclockwise during a tightening and quality cannot be assured that the bolt is tightened with a certain torque angle. The function of orientation tracking was de- sired to be evaluated for the Tensor STB angle and STB pistol tools manufactured by Atlas Copco. To be able to study the orientation of a nutrunner, practical exper- iments were introduced where an IMU sensor was fixed on a battery powered nutrunner. Sensor fusion in the form of a complementary filter was evaluated. The result states that the accelerometer could not be used to estimate the angular dis- placement of tightening due to vibration and gimbal lock and therefore a sensor fusion is not possible. The gyroscope by itself can be used to provide the angular displacement around every axis with high accuracy without taking into account the gimbal lock phenomena or external forces in the form of vibration of the tool. The gyroscope provided data with a probability to measure ±1° in future tightenings by 69,76%. The gyroscope provided data with high accuracy and stability and can be used in real world application and production for true angle functionality of the tools. 

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    Erik Grahn
  • 52.
    Gustavsson, Robert
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering. KTH.
    Lind, Alexander
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering. KTH.
    Utvärdering av energiförbrukning av ett IoT-system för övervakning av hundars rörelsemönster2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Tracy Trackers is currently developing an AI platform which purpose is to monitor a dog's movement pattern. The platform consists of hardware with accelerometer, gyroscope, temperature and humidity sensors attached to the dog. The hardware is connected to a mobile through Bluetooth. A study was conducted to investigate which batteries that are available on the market and which ones that fit best for the prototype. The aim of the study was to find a rechargeable battery with long operat-ing hours that is economically and environmentally viable for future production. Hardware for monitoring the battery voltage characteristics was built to determine differences between kinds of batteries and if there was an optimal type of battery for the specific product. The sensors used by the prototype were studied using os-cilloscopes and a self-constructed circuit in order to be able to determine power consumption at different sampling frequencies. Furthermore, a circuit was built for filtering out certain frequencies to determine the current consumption of the DC-components. The current consumption measured by the tests in this study refers to what draws current in the prototype. The developed hardware can be used for measurements of future prototypes

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    Utvärdering av IoT
  • 53. Gyllencreutz, Erika
    et al.
    Lu, Ke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Abtahi, Farhad
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Lindecrantz, Kaj
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Nordström, Lennart
    Lindqvist, Pelle
    Holzmann, Malin
    Characteristics of variable decelerations and prediction of fetal acidemia2017In: American Journal of Obstetrics and Gynecology, ISSN 0002-9378, E-ISSN 1097-6868, Vol. 216, no 1, p. S507-S507Article in journal (Other academic)
  • 54.
    Ha, Minkeun
    et al.
    KTH, School of Technology and Health (STH).
    Lindh, Thomas
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Distributed Performance Management of Internet of Things as a Service for Caregivers2017In: 2017 IEEE 19TH INTERNATIONAL CONFERENCE ON E-HEALTH NETWORKING, APPLICATIONS AND SERVICES (HEALTHCOM), IEEE, 2017, p. 1-6Conference paper (Refereed)
    Abstract [en]

    This paper presents a multi-layer distributed performance management model for Internet of Things (IoT) as a service for caregivers. Performance monitoring and control of IoT devices and services are vital functions for e-health systems. Cloud-based IoT systems with centralized data centers further underline the need for distributed management. The main contribution of this paper is a model and prototype implementation that combines low-complexity policy-based and conventional network management with cloud computing paradigm, lightweight IoT protocols, and their data models. A case study on monitoring of heart activity demonstrates interworking between OMA Lightweight M2M protocol, Bluetooth low energy GATT services, and Azure IoT hub cloud platform to enable distributed policy-based performance management.

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    fulltext
  • 55.
    Haidari, Bahaman
    et al.
    KTH, School of Technology and Health (STH).
    Holm, Isak
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Verifiering av ERTMS-signalprojektering: Tillämpning mot Estland2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    EU has a framework that strives to interoperability to make it easy to travel and do business with all nations in the EU without the need to change trains or drivers. This report discribes the various laws and regulations that issued and specified by the EU Commission, UNISIG and the Swedish national rules that apply for ERTMS signalling project planning for trackside equipment. Today there is a need to more efficient the signal project planning. To achieve this, a checklist for signaling project planning will be developed that clear show, for example, where an Eurobalise in relation to a signal point should be located by referring to the correct subchapter in the right document.

    The mission of the project is to make it easier to design new production of ERTMS signalling project planning. To make this be possible studies has been done to TSI, SUBSET (the documents that controls and regulates the ERTMS signalling), relevant documents and analysis already implemented signalling project planning on Ådallines.

    The report presents a compilation of the signal project and how the different phases will occur, how they will be implemented and their significance.

    In this report, the group has produced a complete compilation of the processed documents for ERTMS signalling project and a checklist for verification of the ERTMS signalling project.

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    Examensrapport
  • 56.
    Halilović, Armin
    et al.
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Basic science.
    Johnny, Panrike
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    MULTILINEAR MCSHANE INTEGRAL IN R^n2016In: International Journal of Differential Equations and Applications, ISSN 1314-6084, Vol. 15, no 1, p. 12-32Article in journal (Refereed)
    Abstract [en]

    This work studies multilinear McShane-Stieltjes integrals of vector-valued functions defined on intervals in R^n.

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    fulltext
  • 57.
    Halilović, Armin
    et al.
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Basic science.
    Panrike, Johnny
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    MULTILINEAR STIELTJES INTEGRALS OF FUNCTIONS OF SEVERAL VARIABLES2014In: International journal of pure and applied mathematics, ISSN 1311-8080, E-ISSN 1314-3395, Vol. 90, no 4, p. 561-583Article in journal (Refereed)
    Abstract [en]

    In this paper we define and consider multilinear Stieltjes integralsfor vector-valued functions defined on a closed bounded interval in \mathbb{R}^n. Theconvergence of the Stieltjes sums is considered in the Riemann, Moore-Pollardand Henstock-Kurzweil sense.

  • 58.
    Hama-amin, Samman
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Veldre, Andrejs
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Investigation of power supplies used in OSC9502013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    SammanfattningOCS950(Object Controller System 950) är en av Bombardiers produkter som hanterar säkerhetssystemet i järnvägstrafiken. Det består av olika delsystem och strömförsörjs mha nätaggregat (PSU – Power Supply Unit). I den här rapporten undersöks den befintliga PSU74-modellen samt nya switchade nätaggregat som finns på marknaden.Bakgrunden till att Bombardier vill byta ut PSU74 mot ett nytt switchat aggregat är att PSU74 har en vikt på 14 kg och tar stor plats i el-skåp. Ett swichat nätaggregat väger ungefär 1,5 kg och är så pass kompakt att det tar litet utrymme i el-skåpet.Bombardier har medvetet väntat med att gå över till SMPS eftersom tillförlitlighet blir ett problem. Detta problem kan lösas mha redundanta kopplingar. MTBF är den största utmaningen vid övergång till SMPS. MTBF beräkningar för redundanta kopplingar presenteras i rapporten och resultatet visar att ju fler enheter ett system innehåller desto mindre blir MTBF-värdet.I faktainsamlingsdelen beskrivs och förklaras olika viktiga begrepp för att underlätta förståelse av rapporten. MTBF, linjära och switchade nätaggregat är bara några begrepp som tas upp.En studie av PSU74 och en lista över dess viktiga egenskaper presenteras, det är en utgångspunkt för kravspecifikation för nytt switchade nätaggregat. Vissa egenskaper som prioriteras är MTBF, in-och utspänning, vikt och drifttemperatur mm.Ett enkelt kretsschema konstrueras och visar principen för redundant koppling. Kravspecifikationen finns i ett tabellformat. De flesta egenskaper är definierade men vissa är ej fastställta. Bombardier definierar värde på dessa egenskaper efter diskussion med potentiella tillverkare.En alternativ lösning presenteras där ett uppvärmningsförslag av el-skåp läggs fram. Denna metod kan bredda urval av SMPS på marknaden. En omfattad undersökning av marknaden genomförs där olika modeller analyseras baserade på kravspecifikationer. En utmaning är omgivningstemperaturen eftersom de  flesta SMPS tål – 25°C minimum drifttemperatur. Några modeller som uppfyller kriterierna undersöks noggrant och systematiskt. Analys av utvalda SMPS utförs och slutsatser presenteras där för- och nackdelar med respektive modell lyfts fram. Det konstanteras att modell från Cosel TUFS300F28 är ett bra alternativ för ersättning av PSU74.

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    fulltext
  • 59.
    Harch, Gais
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Ullström, Robin
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Automatiserad matchning av relaterad data från olika datakällor2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Social media today contains a lot of information that can add a great value for applications and products by achieve an improved user experience. In some cases, such information cannot be obtained without matching data from one or several data sources through a data fusion.

     

    Eniro Initiatives AB wants to explore opportunities to implement an automated data fusion model by matching companies from its own API to the corresponding company on social media. The problem is that the only completely secured data of matching of all Swedish companies is its corporate identity, which is data that is not available with APIs that origin from foreign companies. The aim was to explore possibilities for the automated way to match related data from different data sources.

     

    In this thesis, a prototype was developed to match companies from Eniro’s API with company pages from Facebook's API. The results from the tests of this prototype shows small deficiencies where redundant information made the prototype able to approve unofficial pages with links to the relevant company, which was not desirable.

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    ExamensrapportGaisRobin
  • 60.
    Hassan, Waleed
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Hellström, Martin
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Realtidsövervakning av multicastvideoström2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The enormous increase in multicast services has shown the limitations of traditional network management tools in multicast quality monitoring. There is a need for new monitoring technologies that are not hardware-based solutions such as increased link throughput, buffer length and capacity to enhance the quality of experience. This paper examines the use of FFmpeg, and OpenCV as well the no-reference image quality assessment algorithm BRISQUE to improve the quality of service as well as the quality of experience. By detecting image quality deficiencies as well as bit errors in the video stream, the QoS and QoE can be improved. The purpose of this project was to develop a monitoring system that has the ability to detect fluctuations in image quality and bit errors in a multicast video stream in real time and then notify the service provider using SNMP traps. The tests performed in this paper shows positive results when using the hybrid solution proposed in this paper, both BRISQUE and FFmpeg alone are not sufficiently adapted for this purpose. FFmpeg has the ability to detect decoding errors that usually occurs due to serious bit errors and the BRISQUE algorithm was developed to analyse images and determine the subjective image quality. According to the test results BRISQUE can be used for multicast video analysis because the subjective image quality can be determined with good reliability. The combination of these methods has shown good results but needs to be investigated and developed further.

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    Multicastövervakning
  • 61.
    Hededal Klincov, Lazar
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Symeri, Ali
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Devising a Trend-break-detection Algorithm of stored Key Performance Indicators for Telecom Equipment2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A problem that is prevalent for testers at Ericsson is that performance test results are continuously generated but not analyzed. The time between occurrence of problems and information about the occurrence is long and variable. This is due to the manual analysis of log files that is time consuming and tedious. The requested solution is automation with an algorithm that analyzes the performance and notifies when problems occur. A binary classifier algorithm, based on statistical methods, was developed and evaluated as a solution to the stated problem. The algorithm was evaluated with simulated data and produced an accuracy of 97.54 %, to detect trend breaks. Furthermore, correlation analysis was carried out between performance and hardware to gain insights in how hardware configurations affect test runs.

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    fulltext
  • 62.
    Hermansson, Rickard
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Hellström, Johan
    KTH, School of Technology and Health (STH).
    Discretionary Version Control: Access Control for Versionable Documents2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A common problem in the workplace is sharing digital documents with coworkers. Forsome companies the problem extends to wanting the documentskept internally backedup and controlling which people in the company has rights to read and revise certaindocuments.This paper shows different systems and models for access control, version control,and distribution of the documents that can be used to create asystem that solves theseproblems.One requirement for this system was a user interface where users can upload, down-load and manage access to their documents. Another requirement was a service thathandles version control for the documents, and a way to quickly connect and distributethe documents. The system also needed to be able to handle access control of the ver-sioned documents on document level, referred to as "fine grained access control" in thispaper.These models and systems were evaluated based on aspects of the access control mod-els, version control systems, and distribution systems andprotocols. After evaluating,appropriate selections were made to create a prototype to test the system as a whole.The prototype ended up meeting the goals that Nordicstationset for the project butonly with basic functionality. Functionality for retrieving any version from a docu-ments history, controlling access for the documents at document level, and a simpleweb based user interface for managing the documents.

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    fulltext
  • 63.
    Herrlin, Emma
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Alternativa reglermetoder för en energieffektiv byggnad2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ungefär 60 % av den totala energianvändningen för uppvärmning (inklusive varmvatten) i Sverige går åt till att värma upp flerbostäder och lokaler, vilket ger en indikation på att det finns potential att minska energianvändningen ytterligare genom att hitta alternativa metoder för styr- och reglering av befintliga värmesystem. En viktig faktor oberoende av vilken metod som används är att veta byggnadens dynamiska egenskaper. Det finns en rad olika metoder på marknaden för att kunna minska energianvändningen och en del av dem är välbeprövande medan andra fortfarande är på forskningsnivå. Den beprövade metoden är prognosstyrning vilket också utvärderades vidare i examensarbetet genom en studie av tidigare utförda arbeten inom området. En gemensam och viktig faktor för att kunna spara energi för uppvärmning i byggnader är att veta byggnadens tidskonstant, även kallad värmetröghet. För att påvisa dess betydelse utfördes simuleringar i ett program som heter TEKNOsim som är utvecklat av Chalmers tekniska högskola. Resultatet från simuleringarna som utfördes för 6 olika scenarier visade att den stora faktorn som påverkade byggnaden var internvärmen från belysning, apparater och personer. En yttre påverkande faktor som också hade betydelse var solavskärmning för fönsterna vilket gav en jämnare rumstemperatur. Då simuleringarna anpassades till två olika driftfall för ventilationssystemet till ”kontorstid” och ”utanför kontorstid” höll sig rumstemperaturen inom ramen för högsta och lägsta temperatur under tiden då kontoret var bemannat. En annan metod som användes var en litteraturstudie för arbeten inom området prognosstyrning. För de arbeten som valdes ut undersöktes två olika leverantörer som är marknadsledande i Sverige, eGain och Kabona. I snitt visade resultaten en besparing på 10–15% för uppvärmningskostnaderna men den individuella spridningen för eGains prognosstyrning var stor. Vissa fastigheter hade ingen besparing alls medan andra hade en besparing på 26%. Den stora spridningen berodde antagligen på att det nya systemet endast varit igång i 6 månader då studiens utfördes, vilket är för kort tid för att få några tillförlitliga resultat. För Kabonas tjänst Ecopilot var resultaten mer jämna.

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    Emma_Herrlin_STH2017.119
  • 64.
    Ho, Henry
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Odelberg, Axel
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Efficient caching of rich data sets2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The importance of a smooth user experience in applications is increasing. To achieve more performance when interacting with resource intensive data it is important to implement an efficient caching method. The goal of this thesis is to investigate how to implement an efficient cache in an Android application. The use case is to download metadata and images of movies from a WebAPI provided by June AB.

    In order to investigate which caching method is the most efficient, a pre-study was done on some of the most common caching methods today. Based on the results of the pre-study, two different caching algorithms were tested and evaluated: First-In First-Out (FIFO) and Least Recently Used (LRU). These two algorithms were then implemented in an Android application.

    The resulting prototype has a responsive user interface capable of caching large amounts of data without noticeable performance loss compared to a non-cached version. The results from the prototype showed that LRU is the better strategy in our use case, however what we discovered was that the buffer size of the cache has the biggest impact on performance, not the cache eviction strategy.

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    thesis
  • 65.
    Håkansson, Max
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Optimering av dataleverans för Internetanslutna TV- applikationer2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As televisions and peripheral devices nowadays often are Internet con- nected and has built-in web browsers that work as a platform for HTML5 applications running JavaScript, the range of applications available on these platforms has increased drastically. However, many suffer from poor performance in terms of data transfer and the user interface is often experienced as slow since the hardware cannot compare to a modern desktop computer. This thesis examines what can be optimized on the networking side. Two optimization methods have been evaluated - caching and compression of data of both the application package and external resources to the end user. Measurements have been made on an existing TV application to identify which parts have biggest room for im- provements. Comparisons between the various solutions show that some methods can speed up specific processes significantly, while other methods even may have a negative effect. The solutions that have shown the best results based on the speed improvements have been implemen- ted in the existing application. Consideration of the suitability of the maintenance of the solutions were also taken.

    The results of these optimizations show that relatively simple methods can significantly improve the user experience for an connected TV appli- cations. For instance, a reduction of about 80 % of the startup time has been measured in the performed tests.

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    fulltext
  • 66.
    Ibrahim, Goran
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Ek, Leonard
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    En processbeskrivning för utveckling av webbaserade system och gränssnitt: En fallstudie av utvecklingsprocesser på GMP-Systems AB2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Business systems lacking a clear interface and subsequently a diminished usability, can lead to limited usage or no usage of parts of the system. It may therefore be critical to have a process outlined for the development of such system and its interface to ensure that all parts of the system are used.   The objective of this case study was to investigate whether it is possible to develop a process description for IT projects at the initial stages of the development phase of a new interface in a system. More specifically, the question investigated in this report follows: 

    “How should a development method or development process for IT systems look to seize scientific, theoretical and technical aspects of Human Computer Interaction (HCI)?”

    A case study of the project was carried out at the company GMP-Systems AB. A literature-study on aspects of Human-Computer Interaction (HCI) was carried out to arrive at a result and answer the question. Further, an analysis was conducted to consider whether the technical implementation of such process can be accomplished by adopting frameworks. In addition, interviews were conducted with users that have interacted with the system, and an analysis was carried out on the feedback provided to develop prototypes for the system. A development method and process description linked to the literature and the experience gained from the projects case study is outlined in the result section. To the client, GMP-Systems, a prototype, a use-case model[1] with user-stories[2] and a sequential diagram[3] will be delivered. 

    Keywords: HCI, evaluation method, Angular JS, Knockout JS, React, Moqups, process description, development method.

    [1] Use-Case model is a description of actions that a user can perform and defines the interaction between the roles of a system to accomplish a goal[2] User stories are a tool in system development to provide a description of the desired functionality, often from an end user perspective.[3] A sequential diagram shows how objects operate with one another and in what order.

     

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    Examensrapport
  • 67.
    Irstad, Noel
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Fredrik, Stjerne
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Governing of access point for stations in an 802.11 network with a repeater to achieve higher throughput: Designing and implementing an algorithm on Inteno's OpenWRT based access points2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When using a wireless repeater in a network, an overlap zone between the repeater and the primary access point that holds the internet connection is created. The theoretical throughput for connections through the repeater is reduced by half since the repeater can’t send and receive data at the same time when using only one channel which was the case in this thesis.

    To solve the problem with the overlap zone, an algorithm that runs in the form of a bash script on two openWRT-based access points where one acts as a repeater and the other one is a gateway with an internet connection was developed. The script uses the signal strength value (RSSI) to decide whether a wireless device is located within the overlap zone by comparing the measured value against a set threshold where the gateway still delivers higher throughput than the repeater. Wireless devices in the overlap zone are blocked on the repeater and will then connect to the gateway instead. Wireless devices that are located outside the overlap zone will connect to the access point that yields the strongest signal strength. The throughput to the gateway was measured at several locations with different signal strengths to both the gateway and the repeater.

    Wireless devices within the overlap zone that were connected to the repeater before the script was run gained a higher throughput after the script was run and made it connect directly to the gateway instead.

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    Governing of access point for stations in an 802.11 network with a repeater to achieve higher throughput
  • 68.
    Johansson, Charlie
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Frid, Martin
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Inomhuspositioneringssystem: Personlig navigation inomhus via mobiltelefon2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The GPS is used today for personal navigation, however GPS performs less well in an in-door environment due to the dependency of line of sight. The IPS, Indoor Positioning Sys-tem, will complement the function of the GPS and open doors for new applications. In this thesis studies of methods and techniques are made to enable IPS for a portable device. These techniques and methods are verified that they could be implemented in a smartphone.A prototype was designed to examine the possibility to navigate in an indoor environment. The prototype was built on a RSSI-based radio fingerprinting method over Bluetooth. This method was integrated with a dead reckoning system using an IMU to follow the motions of the user. Tests and simulations are performed along with the results presented in tables and figures. The result shows that it is possible to navigate using the prototype with a mean error of 0.26m. Results are also showing that two methods are to prefer, as they will com-plement each other’s weaknesses.

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    IPS_prototyp
  • 69.
    Karlsson, Fredrik
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Berg, Fredrik
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Algoritm för automatiserad generering av metadata2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sveriges Radio stores their data in large archives which makes it hard to retrieve specific information. The sheer size of the archives makes retrieving information about a specific event difficult and causes a big problem. To solve this problem a more consistent use of metadata is needed. This resulted in an investigation about metadata and keyword genera-tion.The appointed task was to automatically generate keywords from transcribed radio shows. This included an investigation of which systems and algorithms that can be used to generate keywords, based on previous works. An application was also developed which suggests keywords based on a text to a user. This application was tested and compared to other al-ready existing software, as well as different methods/techniques based on both linguistic and statistic algorithms. The resulting analysis displayed that the developed application generated many accurate keywords, but also a large amount of keywords in general. The comparison also showed that the recall for the developed algorithm got better results than the already existing software, which in turn produced a better precision in their keywords.

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    Algoritm för automatiserad generering av metadata
  • 70.
    Karlsson, Fredrik
    et al.
    KTH, School of Technology and Health (STH).
    Berg, Fredrik
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Algoritm för automatiserad generering av metadata2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sveriges Radio stores their data in large archives which makes it hard to retrieve specific information. The sheer size of the archives makes retrieving information about a specific event difficult and causes a big problem. To solve this problem a more consistent use of metadata is needed. This resulted in an investigation about metadata and keyword genera-tion.The appointed task was to automatically generate keywords from transcribed radio shows. This included an investigation of which systems and algorithms that can be used to generate keywords, based on previous works. An application was also developed which suggests keywords based on a text to a user. This application was tested and compared to other al-ready existing software, as well as different methods/techniques based on both linguistic and statistic algorithms. The resulting analysis displayed that the developed application generated many accurate keywords, but also a large amount of keywords in general. The comparison also showed that the recall for the developed algorithm got better results than the already existing software, which in turn produced a better precision in their keywords.

    Download full text (pdf)
    fulltext
  • 71.
    Karlsson, Kristoffer
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Den intelligenta pumpstationen -Optimering av energiförbrukningoch utveckling avautomatiseringsfunktion förfelhantering2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper has investigated the possibility of optimizing the power consumption of pumps through the control system for a wastewater pumping stations. Further-more, the possibilities of developing new control functions has been investigated, with the purpose to simplify the operation maintenance of the station. To investigate energy consumption, a theoretical model of a pumping station has been made where energy tests for three different control methods have been per-formed. Two of the methods studied were on/off control and a P controller which are commonly used in pump stations. The third method was a Fuzzy controller which, with regard to the level and level change, regulates the speed of the pump.The results from the energy tests showed that on/off control consumed most en-ergy and the Fuzzy controller demonstrated best features to optimize energy con-sumption. The Fuzzy controller’s energy consumption was less in most of the tests compared with the P controller. The Fuzzy controller showed the best properties when the inflow was low relative to the pump’s capacity and the bottom area of the sump was smaller.When investigating new control functions, interviews with management executives has been made to get a picture of the problems that may occur in a pump station. The control functions developed had the purpose of reducing the number of clogged pumps as this was the biggest problem.

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    fulltext
  • 72.
    Karlsson, Tobias
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Bengtsson, Johannes
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Modellering och analys av hjälpkraftsystemet i järnvägsnätet2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report will investigate troubles with voltage drop in the auxiliary power system on different routes in the Swedish railway. The auxiliary power system provides the electrical, telecom and signalling systems with power. The voltage level can be 22 kV three phase or 11 kV three or two phase. The report is based on an investigation from STRI where a standardised approach has been developed. The routes included in the report are three phase and has the rated voltage of 11 kV, 50 Hz.

    The routes have been modulated and simulated in µPAS. To verify the results from the simulations calculations have been made separately. From the results two alternative solutions has been presented. Raise the voltage to 22 kV or change the position of the feeder for long feed. The aim was to lower the voltage drop for each of the solutions. For a quick control the standardised approach can be used. To get more accurate values µPAS is the better alternative.  

    One conclusion was that all examined routes with 11 kV and are normal fed fulfil the demands of ± 10 % of rated voltage. Issues appear when a route is long fed and if the voltage from a frequency converter drops below 11 kV. 

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    fulltext
  • 73.
    Karnik Macaya, Yohanna
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Vattennivåreglering i Avesta Lillfors: På uppdrag av Fortum Generation AB2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report evaluates different methods to create a stable regulation of the water level in the hydro power plant Avesta Lillfors, in county Dalar-na. Another pair of plants are located just 900 m up the stream, which is why the regulation has to act fast. If the water level can be regulated and automatically adjust to the incoming flow, it facilitates the control of the plant.

    A flow chart is created from measurements in the turbine, using the Win-ter-Kennedy method. The results are used for feedforward control. A PID-regulator with feedback is also simulated in a model of the river. This helps finding the parameters that provide a stable, accurate and fast regu-lation. Fuzzy logic control has also been simulated.

    Download full text (pdf)
    fulltext
  • 74.
    Klint, Simon
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Laveskog, Magnus
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Energiövervakning och styrning av snarta hem2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Energy monitoring can lead to lowering energy consumption. This infor-mation would help the user to make decisions in regards to the power us-age. The measurements can also give the user the possibility to study the power quality to find bad loads and minimize the effects on the power grid. The choice of thesis was done to give the users the possibility to affect and monitor their environmental effect in a way that is otherwise not possible. A concept was developed that measure the voltage and current peak, the voltage and current RMS, power factor and the voltage waveform. The measurements are then sent to a server that is also containing a website. With the website the user can monitor their power usage and turn on or off the power consumers on the website. Added to the system is also the pos-sibility to add external sensors to increase the monitoring. The result of the project is a functioning concept to demonstrate. Another big result is the amount of improvements discovered to make it a really good base to con-tinue developing on.

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    Energiövervakning och styrning av snarta hem
  • 75.
    Kljakic, Danijel
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Carlsson, Pontus
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Automatisk detektering av skillnader av Androidenhetersanvändargränssnitt2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    User interfaces can look different on different Android devices and it is difficult to tailor anapplication to all Android devices. The goal with this project was to develop a tool that canuse a correct image of a user-interface and find differences in other images taken from otherAndroid devices. A tool was developed from scratch and it proved accurate in most cases.The tool could both find differences and report how large the difference was.

    Download full text (pdf)
    fulltext
  • 76.
    Koyuncu, Yasin
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Aljic, Muhamed
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Lastbalansering av applikationstjänster för dynamisk URL hantering: En studie om prestandan för lastbalanseringsalgoritmer på transportlagret2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company Speed Services provides a large number of services such as safekeeping boxes, photo booths and interactive stalls on public places. Speed Services got difficulties with long response times on their servers and gave an assignment to studyand develop a solution with shorter response times.The produced result is a prototype that utilizes load balancing to spread the requests to different servers. Those servers utilize in turn a cache to retrieve data from the database efficient and minimize network load, especially on the database server. The prototype has been tested via automatic requests and an analysis had been performed based on the collected data which showed that the Least Connections loadbalancing algorithm is the most optimal solution.

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    Lastbalansering_Av_Applikationstjänster
  • 77.
    Kuehn, Daniel
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Ljunggren, Sofia
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Refining a Network Model Concerning Network Security Risk Analysis2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    P²CySeMoL is a framework in which security risks are calculated and presented with a value referring to the probability that an attack will succeed in a system, mainly SCADA systems.

    This thesis covers the creation of a more granular network module for the P²CySeMoL security riskanalysis framework to better be able to represent a network in concrete modules and to enable security riskanalysis on a network infrastructure at a greater detail.

    This paper outlines the creation of a network module with the base in the OSI model. It is replicated in a way that the network module is an extension to the P²CySeMoL metamodel, without interfering and restructuring it. It also covers a smaller survey to verify and get feedback about the created module from security and network experts and analysis of the survey.

    The conclusion is made that the network module is a good base to build upon and reflects to good degree a model needed to do security risk analysis on a network infrastructure and suggestions about further validation and research to improve the module are outlined.

    This thesis was produced in cooperation with Spotify AB and parts of the team behind P²CySeMoL at the ICS department at KTH.

    Download full text (pdf)
    Bachelor Thesis - Final Print Version 2014
  • 78.
    Kåhre, Jonathan
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Boeryd, David
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Resolution for dynamic configuration of consumer placed equipment2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Networking devices and other internet-enabled hardware require configuration to work correctly and manually configuring each and every device is expensive and slow. In order to relieve these problems, the concept of automatic configuration was conceived. For this to be possible, a device must be able to not only find the location of the host keeping the configuration but also negotiate how the configuration will take place. In this paper, two new protocols are proposed to resolve configuration servers for the device to negotiate with and the negotiation protocol to arrange the actual configuration procedure. Additionally a business model is presented in order to structure and maintain the system supplementing existing production and sales.

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    fulltext
  • 79.
    Larsson, Andreas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Segerås, Tony
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Automated invoice handling with machine learning and OCR2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Companies often process invoices manually, therefore automation could reduce manual labor. The aim of this thesis is to evaluate which OCR-engine, Tesseract or OCRopus, performs best at interpreting invoices. This thesis also evaluates if it is possible to use machine learning to automatically process invoices based on previously stored data.

    By interpreting invoices with the OCR-engines, it results in the output text having few spelling errors. However, the invoice structure is lost, making it impossible to interpret the corresponding fields. If Naïve Bayes is chosen as the algorithm for machine learning, the prototype can correctly classify recurring invoice lines after a set of data has been processed.

    The conclusion is, neither of the two OCR-engines can interpret the invoices to plain text making it understandable. Machine learning with Naïve Bayes works on invoices if there is enough previously processed data. The findings in this thesis concludes that machine learning and OCR can be utilized to automatize manual labor.

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    ThesisAndreasTony
  • 80.
    Lindh, Thomas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Orhan, Ibrahim
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Performance Monitoring and Control in Contention-Based Wireless Sensor Networks2009In: Proceedings of the 2009 6th International Symposium on Wireless Communication Systems, ISWCS'09, NEW YORK: IEEE conference proceedings, 2009, p. 507-511Conference paper (Refereed)
    Abstract [en]

    This paper presents a method for performance monitoring and control in wireless body sensor networks based on measurement feedback. Test results using a prototype implementation of the method are also analyzed. The method has been evaluated for demanding healthcare related applications in wireless personal area networks.

  • 81.
    Ljungström, Andreas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Panikian, Jack
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Implementation and Evaluation of Bluetooth Low Energy for Musical Devices2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper presents the possibility to transfer Musical Instrument Digital Interface messages overBluetooth Low Energy. The main problem was to transmit the messages between two computers inless than 10 milliseconds. Anything above 10 milliseconds could be noticed as a delay by the personplaying or listening to the music. A prototype was written which could transfer Musical InstrumentDigital Interface messages over Bluetooth Low Energy between two Linux-computers together with atesting framework which was used to make measurements. The prototype was written in the languageC++ with the BlueZ library. The time it took for one packet to travel back and forth from the computerswas clocked to get an estimation of the time it took for a packet to travel from one computer to theother. The measured results showed that it was possible to reach the desired time of 10 milliseconds.The results can also be used when considering development of other kind of equipment and/or applicationsthat implements the use of Bluetooth Low Energy.

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    implementation and evaluation of bluetooth low energy for musical devices
  • 82.
    Lundberg, Thomas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Heimonen, Alexander
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    System Support for Cost Analysis2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this thesis was to analyze and evaluate possible matches betweeninvoices and assets from two different systems. This degree project was done incooperation with DGC, a network operator with an network stretching beyondthe borders of Sweden. The network solutions are provided through rentingthe copper and fiber connections (access services) from network owners andusing these to connect customers to their own network backbone. As a firststep towards a clearer overview of which customer pays for what, there was aneed to connect incomes generated from a paying customer with the outcomegenerated for renting an asset.  The approach taken to solve the problem involved analyzing the theory offuzzy logic and developing system support for matching using fuzzy logic ina .NET Windows Presentation Foundation application using the Model ViewViewModel design pattern.  The result became a fully functional implementation, integrated in an alreadyexisting tool called Oasis. This new tool allows users to quickly createpermanent mappings between invoices and assets.  This solution will decrease the time it would have taken to manually map theinvoices to the assets tremendously. This will make future steps in automatedcost analysis possible, giving the company a better overview of their financesand helping them to more easily find strange occurrences where an asset is beingrented without a customer paying for it, or vice versa.

  • 83.
    Lundmark, Magnus
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Dahlman, Carl-Johan
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Differential privacy and machine learning: Calculating sensitivity with generated data sets2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Privacy has never been more important to maintain in today’s information society. Companies and organizations collect large amounts of data about their users. This information is considered to be valuable due to its statistical usage that provide insight into certain areas such as medicine, economics, or behavioural patterns among individuals.

    A technique called differential privacy has been developed to ensure that the privacy of individuals are maintained. This enables the ability to create useful statistics while the privacy of the individual is maintained. However the disadvantage of differential privacy is the magnitude of the randomized noise applied to the data in order to hide the individual.

    This research examined whether it is possible to improve the usability of the privatized result by using machine learning to generate a data set that the noise can be based on. The purpose of the generated data set is to provide a local representation of the underlying data set that is safe to use when calculating the magnitude of the randomized noise.

    The results of this research has determined that this approach is currently not a feasible solution, but demonstrates possible ways to base further research in order to improve the usability of differential privacy. The research indicates limiting the noise to a lower bound calculated from the underlying data set might be enough to reach all privacy requirements. Furthermore, the accuracy of the machining learning algorithm and its impact on the usability of the noise, was not fully investigated and could be of interest in future studies. 

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    fulltext
  • 84.
    Lundmark, Staffan
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Ekholm, Gustav
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Successiv transponering av luftledningar för högspändväxelström2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Three phase high voltage alternating current overhead line systems are associated with losses along the lines and disrupting magnetic fields surrounding the conductors. These negative effects could possibly be combated by twisting the conductors. The twist was achieved by gradually shifting the conductors positions (transposition) over each span of transmission line. A test circuit with a stainless steel wire was made. Geometric and electromagnetic modelling of a successively transposed power line was performed. A miniature three phase overhead line model was constructed.. The model was based on the results from the geometric modeling and data from a real △-configured power system application. Experiments were made with both the steel wire circuit and the overhead line model. Voltage drops in the circuit with a straight - and twisted wire was measured with an oscilloscope. Magnetic flux around the overhead line models were measured with a solenoid. The results from the experiments showed that twisting the conductors resulted in an increase in inductance and a decrease in capacitance. Regarding the magnetic fields, indications of an overall decrease was observed with the twisted configurations compared to the straight. Twisted overhead lines could be viable when an overall decrease in magnetic field is needed. Due to uncertainties in the magnetic field measurements, more extensive experiments should be conducted in order to solidify the results of this work.

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    fulltext
  • 85.
    Maan, Narbir Singh
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Hanchi, Hamza
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Secure Access for Public Clients to Web API:s with Minimum Performance Loss2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A lot of information nowadays is made available through Web APIs on the Internet and without security and encryption; it is very easy for malicious users to access confidential information.

    The goal was to find out what different mechanisms that are available for providing a safe communication with a web API from web clients and mobile applications with little as possible impact on the performance. Learning, implementing and maintaining the mechanisms are also im- portant aspects looked at in the evaluation.

    Many mechanisms are available for use to secure the communication but not all are suitable for public clients. The suitable mechanisms are Digest authentication and OAuth 2.0. The chosen mechanisms were developed, tested and evaluated in regard to safety, performance impact and usabil- ity from a company perspective.

    The authentication and authorization mechanism, which was the most suitable, was OAuth 2.0as it has least impact on performance and better security features than the other mechanisms.

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    Secure Access for Public Clients to Web APIs with Minimum Performance Loss
  • 86.
    Maatson, Mats
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Denke, Joel
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Prestandaanalys av cache i webbmiljö2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Dramatify is providing TV and film production companies with a software as a service for project management. The web application is accessible from any device with a modern web browser from anywhere in the world. Dramatify were having performance issues with high latency and needed help to implement cache for maximum performance gain. To solve the problem, a research was conducted where information about suitable ap-plications to implement, test and analyze prototypes for storing data in cache.

    The result was two prototypes, one for the client and one for the server, for managing cache. Performance testing was done with automatic tests on multiple devices in different web browsers. The tests was collecting rele-vant data to measure the performance in conjunction to the original imple-mentation. When analyzing the collected test data, it showed that the client prototype was 32 percent faster and that the server prototype was 21 per-cent faster than the original implementation.

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    prestandaanalys av cache i webbmiljö
  • 87.
    Mahmoud, Diyari
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Elmiljö och potentialutjämning2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Potentialskillnader mellan elektriskt utsatta delar och andra åtkomliga ledande delar i byggnaden eller anläggningar kan orsaka livsfarliga elektriska urladdningar (strömgenomgångar) vid beröring. Potentialskillnader orsakar även problem för elektriska apparater att fungera tillfredsställande i sin omgivning. Syftet med studien var att undersöka och identifiera uppkomsten till potentialskillnader samt de olika tolkningskonflikter som finns vid förbyggandet av problemen. Dagens elmiljöproblem beror till stor del på den snabba teknikutvecklingen av elektroniken vi använder. För att lösa en stor del ut detta problem utför man potentialutjämning. Resultatet av denna studie visar att skyddsutjämning ska utföras i alla anläggningar. Det skyddar mot elchock i byggnader och industriella anläggningar. Funktionsutjämning upprätthåller utrustningens funktionssäkerhet i industriella anläggningar och är inte ett krav. Den skiljer sig beroende på nivå av känslig miljö. Denna studie utfördes som examensarbete på Kungliga Tekniska Högskolan för Ramböll Sverige AB. Tolkningarna har gjorts utifrån Elinstallationsreglerna, SEK Handbok 413 samt SEK Handbok 449.

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    Elmiljö och potentialutjämning
  • 88.
    Melinder, Jenny
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Lagerström, Ulrika
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Kluriga webbgränssnitt som förvirrar låntagare: Hur Nordeas webbgränssnitt kan förbättras genom användarcentrerad design2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The society is becoming more digital, this is affecting bank systems and customer relations. Nordea is working hard to keep up with the digitalization to sustain and satisfy the customer needs. Digital systems are decreasing the personal contact between the bank and its customers, how is this affecting the relation? This study examines customers vision as well as Nordea and their competitor’s way of working with digital mortgage. Nordea’s interface is evaluated as digitalizing allows website to be the bank’s public face and the first thing costumer meet when applying for digital bank errands. The study aims to develop improvements for Nordea’s design choices and interface. The inquiry has been carried out in the form of interviews and user tests. The result of the study accounts for the flaws in the system and the customers wish of improvement. A prototype with enhancements and suggestions of change for Nordea’s webpage is presented in the end of the report.

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    Kluriga webbgränssnitt som förvirrar låntagare
  • 89.
    Mårtensson, Anders
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    User Experinences in 3D2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    3D user interfaces are common today when for example doing industrial design, architecture and 3dmodelling but they are not commonly used in regular interfaces. The hardware requirements for suchinterfaces are not difficult to reach with today’s computers, laptops and mobile devices with only in-tegrated graphics cards.The report found that users of 3D interfaces found them more fun to use and gives a better overviewwhen viewing dense information. Problems exists when using small screens and reading text. Futureimprovements to software tools and APIs as well as improvements in hardware, and new technologiessuch as virtual- and augmented reality will make 3D interfaces easier to develop, use and run.

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    UserExperiencesIn3D
  • 90.
    Niemelä, Jimmy
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Impostor Rendering with Oculus Rift2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report studies impostor rendering for use with the virtual reality head mounted display Oculus Rift. The technique is replacing 3D models with 2D versions to speed up rendering, in a 3D engine. It documents the process of developing a prototype in C++ and DirectX11 and the required research needed to complete the assignment. Included in this report are also the steps involved in getting Oculus Rift support to work in a custom 3D engine and measuring the impact of impostor rendering when rendering to two screens of the head mounted display. The goal was to find the maximum models the engine could draw, while keeping the frame rate locked at 60 frames per second. 2 testers at Nordicstation came to the conclusion that 40-50 meters was the optimal distance for impostor rendering. Any closer and the flatness was noticeable. The results showed a clear improvement in frame rate when rendering a graphically intensive scene. The end result showed that the goal could be achieved at a maximum of 3000 trees with 1000 leaves. Impostor rendering was deemed effective when drawing beyond 500 trees at a time. Less than that and the technique was not needed to achieve 60 frames per second.

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    ImpostorRenderingWithOculusRift
  • 91.
    Nilstadius, Gustaf
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Duda, Robin
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Evaluation of push/pull based loadbalancing in a distributed loggingenvironment2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report compares the characteristics of push/pull load balancing techniques usedin the context of a logging system. The logging system is expected to handle a largevolume of events. The load balancing techniques are evaluated with focus onthroughput during high load. The testing scenarios includes the use of a traditionalload balancer (push-based) and the use of messaging queues (pull-based and indirectlycontext aware) in its place. The ultimate goal of the report is to determine the feasibilityof using a messaging queue rather than a traditional load balancer in a distributedlogging system. Tests were conducted measuring the throughput of multiple setupswith different load balancers. The conclusion of this report is that both messagingqueues and load balancing are equally feasible in a logging context.

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    fulltext
  • 92.
    Nyström, Simon
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Lönnegren, Joakim
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Processing data sources with big data frameworks2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Big data is a concept that is expanding rapidly. As more and more data is generatedand garnered, there is an increasing need for efficient solutions that can be utilized to process all this data in attempts to gain value from it. The purpose of this thesis is to find an efficient way to quickly process a large number of relatively small files. More specifically, the purpose is to test two frameworks that can be used for processing big data. The frameworks that are tested against each other are Apache NiFi and Apache Storm. A method is devised in order to, firstly, construct a data flow and secondly, construct a method for testing the performance and scalability of the frameworks running this data flow. The results reveal that Apache Storm is faster than Apache NiFi, at the sort of task that was tested. As the number of nodes included in the tests went up, the performance did not always do the same. This indicates that adding more nodes to a big data processing pipeline, does not always result in a better performing setup and that, sometimes, other measures must be made to heighten the performance.

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    Processing data sources with big data frameworks
  • 93.
    Ogeborg, Marcus
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Widerberg, Vincent
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Schemaläggning med hjälp av maskininlärning2017Independent thesis Basic level (Higher Education Diploma (Fine Arts)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study has been analyzing if machine learning could be useful to work-relatedscheduling. The analysis was based on predictions generated by prototypes usingbusiness calendars. The business calendars were collected from two service and installationcompanies in the Stockholm region. An analysis was conducted regardingif the application could be practically applied to devices such as a smartphone. Theanalysis was based on tests regarding the prototypes required time to perform theirtasks.Three prototypes were developed with algorithms that made them predictive. Density-based Spatial Clustering of Applications with Noise (DBSCAN), Logistic Regressionand Weighted K-Nearest Neighbors (wKNN) were the implemented algorithms.DBSCAN was the best-performing algorithm according to the tests. However, a conclusioncould not be found concerning whether machine learning could be useful.The number of successful predictions did not exceed the number of available timeson concerned days, which was assumed as unsatisfying results. In addition, the prototypesneeded a significant amount of resources which could be a problem in practicaluse.

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    Rapport
  • 94.
    Oldsberg, Patrik
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Field Service Support with Google Glass and WebRTC2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Internet is dramatically changing the way we communicate, and it is becoming increasingly important for communication services to adapt to context in which they are used.

    The goal of this thesis was to research how Google Glass and WebRTC can be used to create a communication system tailored for field service support.

    A prototype was created where an expert is able to provide guidance for a field technician who is wearing Google Glass. A live video feed is sent from Glass to the expert from which the expert can select individual images. When a still image is selected it is displayed to the technician through Glass, and the expert is able to provide instructions using real time annotations.

    An algorithm that divides the selected image into segments was implemented using WebGL. This made it possible for the expert to highlight objects in the image by clicking on them.

    The thesis also investigates different options for accessing the hardware video encoder on Google Glass.

    Download full text (pdf)
    Field Service Support with Google Glass and WebRTC
  • 95.
    Orfanidis, Charalampos
    et al.
    Uppsala universitet, Datorarkitektur och datorkommunikation.
    Feeney, Laura Marie
    Uppsala universitet, Datorarkitektur och datorkommunikation.
    Jacobsson, Martin
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering. Uppsala universitet, Datorarkitektur och datorkommunikation.
    Measuring PHY layer interactions between LoRa and IEEE 802.15.4g networks2017In: 2017 IFIP Networking Conference (IFIP NETWORKING) and Workshops, Institute of Electrical and Electronics Engineers (IEEE), 2017Conference paper (Refereed)
    Abstract [en]

    Advances in low power wireless communication have resulted in new radio technologies that can achieve long distance communication in energy efficient ways. An emerging problem in this scenario is interference between networks that share the same medium. The fact that these networks have a long transmission range increases the possibility of interference even more. Thus the investigation of how different networks can share the medium independently in a optimal way becomes an essential requirement for the IoT vision. In this poster, we present the first step of this investigation, which is measuring how LoRa and IEEE 802.15.4g PHY layers interfere.

  • 96.
    Orfanidis, Charalampos
    et al.
    Uppsala universitet, Datorarkitektur och datorkommunikation.
    Feeney, Laura Marie
    Uppsala universitet, Datorarkitektur och datorkommunikation.
    Jacobsson, Martin
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering. Uppsala universitet, Datorarkitektur och datorkommunikation.
    Gunningberg, Per
    Uppsala universitet, Datorarkitektur och datorkommunikation.
    Investigating interference between LoRa and IEEE 802.15.4g networks2017In: Proc. 13th International Conference on Wireless and Mobile Computing, Networking and Communications, IEEE Computer Society, 2017, p. 441-448Conference paper (Refereed)
    Abstract [en]

    The rapid growth of new radio technologies for Smart City/Building/Home applications means that models of cross-technology interference are needed to inform the development of higher layer protocols and applications. We systematically investigate interference interactions between LoRa and IEEE 802.15.4g networks. Our results show that LoRa can obtain high packet reception rates, even in presence of strong IEEE 802.15.4g interference. IEEE 802.15.4g is also shown to have some resilience to LoRa interference. Both effects are highly dependent on the LoRa radio's spreading factor and bandwidth configuration, as well as on the channelization. The results are shown to arise from the interaction between the two radios' modulation schemes. The data have implications for the design and analysis of protocols for both radio technologies.

  • 97.
    Orrevad, Gustav
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Ömsesidig koppling mellan parallellgående friledningar2015Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    Parallel overhead power lines induce voltage in one another, which in turn drives a current. In this report an investigation is made in how asymmetrical short circuits on an overhead power line influence the cur-rent in a parallel overhead power lines due to the inductive coupling be-tween the power lines and which hazards it can cause for the electrical delivery dependability as well as high voltage workers.The aim with this bachelor thesis is to increase the accuracy in fault cur-rent calculation in the Vattenfall electricity grid as well as to increase the knowledge within Vattenfall of the phenomena of inductive coupling and the hazards which comes with it.The report could ascertain that inductive coupling can lead to danger for electrical delivery dependability and that there exists a need of analysis on specific parallel overhead power lines within the Vattenfall electricity grid.

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    fulltext
  • 98.
    Oucif, Kadday
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Evaluation of web scraping methods: Different automation approaches regarding web scraping using desktop tools2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A lot of information can be found and extracted from the semantic web in different forms through web scraping, with many techniques emerging throughout time.

    This thesis is written with the objective to evaluate different web scraping methods in order to develop an automated, performance reliable, easy implemented and solid extraction process. A number of parameters are set to better evaluate and compare consisting techniques.

    A matrix of desktop tools are examined and two were chosen for evaluation. The evaluation also includes the learning of setting up the scraping process with so called agents. A number of links gets scraped by using the presented techniques with and without executing JavaScript from the web sources.

    Prototypes with the chosen techniques are presented with Content Grabber as a final solution. The result is a better understanding around the subject along with a cost-effective extraction process consisting of different techniques and methods, where a good understanding around the web sources structure facilitates the data collection. To sum it all up, the result is discussed and presented with regard to chosen parameters. 

    Download full text (pdf)
    fulltext
  • 99.
    Palm, Emanuel
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Graphics’ Card Utility withWebGL and N-Buffering: Improving performance using N-buffer strategies with WebGL2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis covers the utilization of N buffers in order to reduce resource contention on an abstract WebGL machine, and subsequently freeing up machine processing time. The buffers touched are frame buffers and vertex buffers.

    The paper also briefly covers the purpose and function of N buffering in relation to graphics and the function of a WebGL machine, the research and production of benchmark prototypes, some relevant benchmark results, and analysis and conclusions.

    The conclusion is made that the use of N>1 buffering is a potentially viable strategy for increasing WebGL performance, and some theories are outlined and suggestions given for further research to be made for the resolving of how this performance gain may be improved.

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    N-Buffering and WebGL
    Download (zip)
    Cloud Prototype
  • 100.
    Papadakis, Alexander
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Falge, Emil
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Sensorbaserad riskbedömning av belastningsbesvär2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Musculoskeletal disorders (MSD) is a rising problem in society leading to several socio-economic problems. In combination of the trend of an aging population, MSD can cause even more challenges in the future. Expanding the knowledge of ergonomics is a good way to reduce the risk of stress injury. Today, a visual assessment of ergonomics is primarily used. These observations are individual and not consistent. Availability of cheaper and smaller Inertial Measurement Unit (IMU) has increased the possibility of using objective measurements instead of subjective observations.

    In this thesis work, the Texas Instruments SensorTag CC2650 was used as a sensor, because it is cheap and has many built-in sensors where the 9-axis motion sensor was the most sought one. A web-based development environment called Node-RED was used to develop a prototype and the sensor was connected to a smartphone along with Texas Instruments own application. The data from the sensor was sent from the smartphone to the web application. Measurements were performed on an arm to measure the load on a shoulder, when the hand's position passed the height of the shoulder it indicates that there is a risk of musculoskeletal disorders after an amount of time. To calculate the angle of the arm, sensor fusion of an accelerometer and a gyroscope were used together with a complementary filter.

    Developed system was evaluated by series of tasks exposing the shoulder to a higher risk e.g., painting compare to lower risk tasks e.g., paper sorting. It turned out that measurement are useful for assessment of the risk. However, there are known limitations like low sampling rate of 5Hz (due to limitation in the android app from Texas Instruments). Adding magnetometer to the sensor fusion and evaluation of reliability of calculations are the next natural steps for future work.

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    Rapport exjobb
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