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  • 1.
    Abid, Muhammad Zeeshan
    KTH, School of Information and Communication Technology (ICT). Technische Universität Braunschweig.
    A Multi-leader Approach to Byzantine Fault Tolerance: Achieving Higher Throughput Using Concurrent Consensus2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Byzantine Fault Tolerant protocols are complicated and hard to implement.Today’s software industry is reluctant to adopt these protocols because of thehigh overhead of message exchange in the agreement phase and the high resourceconsumption necessary to tolerate faults (as 3 f + 1 replicas are required totolerate f faults). Moreover, total ordering of messages is needed by mostclassical protocols to provide strong consistency in both agreement and executionphases. Research has improved throughput of the execution phase by introducingconcurrency using modern multicore infrastructures in recent years. However,improvements to the agreement phase remains an open area.

    Byzantine Fault Tolerant systems use State Machine Replication to tolerate awide range of faults. The approach uses leader based consensus algorithms for thedeterministic execution of service on all replicas to make sure all correct replicasreach same state. For this purpose, several algorithms have been proposed toprovide total ordering of messages through an elected leader. Usually, a singleleader is considered to be a bottleneck as it cannot provide the desired throughputfor real-time software services. In order to achieve a higher throughput there is aneed for a solution which can execute multiple consensus rounds concurrently.

    We present a solution that enables multiple consensus rounds in parallel bychoosing multiple leaders. By enabling concurrent consensus, our approach canexecute several requests in parallel. In our approach we incorporate applicationspecific knowledge to split the total order of events into multiple partial orderswhich are causally consistent in order to ensure safety. Furthermore, a dependencycheck is required for every client request before it is assigned to a particular leaderfor agreement. This methodology relies on optimistic prediction of dependenciesto provide higher throughput. We also propose a solution to correct the course ofexecution without rollbacking if dependencies were wrongly predicted.

    Our evaluation shows that in normal cases this approach can achieve upto 100% higher throughput than conventional approaches for large numbers ofclients. We also show that this approach has the potential to perform better incomplex scenarios

  • 2.
    Al Tayr, Hydar
    et al.
    KTH, School of Information and Communication Technology (ICT).
    Al Hakim, Mahmud
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Mobile Ajax2008Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report describes a master thesis performed at SICS (Swedish Institute of Computer Science) and KTH (The Royal Institute of Technology) in Stockholm.

    Ajax stands for "Asynchronous JavaScript and XML" and it's not a programming language, but a suite of technologies used to develop web applications with more interactivity than the traditional web pages.

    Ajax applications can be adapted for mobile and constrained devices. This has been called Mobile Ajax. While the technique is the same, Mobile Ajax generally is considered to be a special case of Ajax, because it deals with problems specific to the mobile market.

    The purpose of this thesis has been to examine which possibilities and disadvantages has the Mobile Ajax from developers and users perspective. In addition we compare Mobile Ajax with Java Micro Edition (Java ME) and Flash Lite.

    This has been done through literature studies and development of a databased chat client (MAIM -Mobile Ajax Instant Messenger). The application sends and receives direct messages in real time between differently mobile devices. Then MAIM application has been compared with our own developed Java ME and Flash Lite chat clients.

    We have tested all three applications with different models of mobile devices and on different web browsers. The results have shown that mobile Ajax makes possible the creation of sophisticated and dynamic mobile web applications and is better than the classic web application model, but this requires that the mobile device has a modern and compatible web browser like Opera mobile.

     

  • 3.
    Al-Zubaidy, Hussein
    et al.
    KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Fodor, Viktoria
    KTH, School of Electrical Engineering (EES), Network and Systems engineering. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Dán, György
    KTH, School of Electrical Engineering (EES), Network and Systems engineering. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Flierl, Markus
    KTH, School of Electrical Engineering (EES), Information Science and Engineering. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Reliable Video Streaming With Strict Playout Deadline in Multihop Wireless Networks2017In: IEEE transactions on multimedia, ISSN 1520-9210, E-ISSN 1941-0077, Vol. 19, no 10, p. 2238-2251Article in journal (Refereed)
    Abstract [en]

    Motivated by emerging vision-based intelligent services, we consider the problem of rate adaptation for high-quality and low-delay visual information delivery over wireless networks using scalable video coding. Rate adaptation in this setting is inherently challenging due to the interplay between the variability of the wireless channels, the queuing at the network nodes, and the frame-based decoding and playback of the video content at the receiver at very short time scales. To address the problem, we propose a low-complexity model-based rate adaptation algorithm for scalable video streaming systems, building on a novel performance model based on stochastic network calculus. We validate the analytic model using extensive simulations. We show that it allows fast near-optimal rate adaptation for fixed transmission paths, as well as cross-layer optimized routing and video rate adaptation in mesh networks, with less than 10% quality degradation compared to the best achievable performance.

  • 4. Andjelkovic, Igor
    et al.
    Artho, Cyrille
    Trace Server: A Tool for Storing, Querying and Analyzing Execution Traces2011In: Proc. JPF Workshop 2011, 2011Conference paper (Refereed)
  • 5. Andræ, A. S. G.
    et al.
    Möller, Patrik
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Liu, J.
    Uncertainty estimation by Monte Carlo simulation applied to life cycle inventory of cordless phones and microscale metallization processes2004In: Proc.Int.Conf.Asian Green Electron., 2004, p. 206-217Conference paper (Refereed)
    Abstract [en]

    This paper addressed the question whether there is an environmental advantage of using DECT phones instead of GSM phones in offices. The paper also addresses the environmental compatibility of Electrochemical Pattern Replication (ECPR) compared to classical photolithography based microscale metallization (CL) for pattern transfer. Both environmental assessments consider electricity consumption and CO2 emissions. The projects undertaken were two comparative studies of DECT phone/GSM phone and ECPR/CL respectively. The research method used was probabilistic uncertainty modelling with a limited number of inventory parameters used in the MATLAB tool. Within the chosen system boundaries and with the uncertainties added to input data, the ECPR is to 100 % probability better than CL and the DECT phone is to 90% better than the GSM phone.

  • 6.
    Annergren, Mariette
    et al.
    KTH, School of Electrical Engineering (EES), Automatic Control.
    Larsson, C. A.
    MOOSE2—A toolbox for least-costly application-oriented input design2016In: SoftwareX, ISSN 2352-7110, Vol. 5, p. 96-100Article in journal (Refereed)
    Abstract [en]

    MOOSE2 is a MATLAB®-based toolbox for solving least-costly application-oriented input design problems in system identification. MOOSE2 provides the spectrum of the input signal to be used in the identification experiment made to estimate a linear parametric model of the system. The objective is to find a spectrum that minimizes experiment cost while fulfilling constraints imposed in the experiment and on the obtained model. The constraints considered by MOOSE2 are: frequency or power constraints on the signal spectra in the experiment, and application or quality specifications on the obtained model.

  • 7.
    Arrospide Echegaray, Daniel
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Utvärdering av Självstyrandes-utvecklarramverket2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Within software engineering there is a diversity of process methods where each one has its specific purpose. A process method can be described as being a repeatable set of step with the purpose to achieve a task and reach a specific result. The majority of process methods found in this study are focused on the software product being developed. There seems to be a lack of process methods that can be used by software developers for there individual soft- ware process improvement. Individual software process improvement, refers to how the in- dividual software developer chooses to structure their own work with the purpose to obtain a specific result

    The Self-Governance Developer Framework (also called SGD-framework) whilst writing this is a newly developed process framework with the purpose of aiding the individual soft- ware developer to improve his own individual software process. Briefly explained the framework is intended to contain all the activities that can come up in a software project. The problem is that this tool has not yet been evaluated and therefore it is unknown if it is relevant for its purpose. To frame and guide the study three problem questions has been for- mulated (1) Is the framework complete for a smaller company in regards to it activities? (2) How high is the cost for the SGD-framework in regard of time?

    The goal of the study is to contribute for future studies for the framework by performing an action study where the Self-Governance Developer Framework is evaluated against a set of chosen evaluation criteria.

    An inductive qualitative research method was used when conducting the study. An induc- tive method means that conclusions are derived from empirically gathered data and from that data form general theories. Specifically, the action study method was used. Data was gathered by keeping a logbook and also time logging during the action study. To evaluate the framework, some evaluation criteria was used which were (1) Completeness, (2) Se- mantic correctness, (3) Cost. A narrative analysis was conducted over the data that was gathered for the criteria. The analysis took the problem formulations in regard.

    The results from the evaluation showed that the framework was not complete with the re- gards of the activities. Although next to complete as only a few activities were further needed during the action study. A total of 3 extra activities were added over the regular 40 activities. Around 10% of the time spent in activities were in activities outside of the Self- Governance Developer Framework. The activities were considered to finely comminute for the context of a smaller company. The framework was considered highly relevant for im- proving the individual software developers own process. The introduction cost in this study reflect on the time it took until the usage of the framework was considered consistent. In this study it was approximately 24 working days with a usage about 3.54% of an eight-hour work day. The total application cost of usage of the framework in the performed action study was on average 4.143 SEK/hour or 662,88 SEK/month. The template cost used was on 172.625 SEK/hour. 

  • 8. Artho, Cyrille
    et al.
    Biere, Armin
    Advanced Unit Testing—How to Scale Up a Unit Test Framework2006In: Proc. Workshop on Automation of Software Test (AST 2006), 2006, p. 462-465Conference paper (Refereed)
  • 9. Artho, Cyrille
    et al.
    Biere, Armin
    Applying Static Analysis to Large-Scale, Multithreaded Java Programs2001In: Proc. 13th ASWEC, 2001, p. 68-75Conference paper (Refereed)
  • 10. Artho, Cyrille
    et al.
    Chen, Zhongwei
    Honiden, Shinichi
    AOP-based automated unit test classification of large benchmarks2007In: Proc. 3rd Int. Workshop on Aspect-Oriented Software Development (AOAsia 2007), 2007, Vol. 2, p. 17-22Conference paper (Refereed)
  • 11. Artho, Cyrille
    et al.
    Gros, Quentin
    Rousset, Guillaume
    Precondition Coverage in Software Testing2016In: Proc. 1st Int. Workshop on Validating Software Tests (VST 2016), IEEE conference proceedings, 2016Conference paper (Refereed)
    Abstract [en]

    Preconditions indicate when it is permitted to use a given function. However, it is not always the case that both outcomes of a precondition are observed during testing. A precondition that is always false makes a function unusable, a precondition that is always true may turn out to be actually an invariant. In model-based testing, preconditions describes when a transition may be executed from a given state. If no outgoing transition is enabled in a given state because all preconditions of all outgoing transitions are false, the test model may be flawed. Experiments show a low test coverage of preconditions in the Scala library. We also investigate preconditions in Modbat models for model-based testing, in that case, a certain number of test cases is needed to produce sufficient coverage, but remaining cases of low coverage indeed point to legitimate flaws in test models or code.

  • 12.
    Artho, Cyrille
    et al.
    KTH, School of Computer Science and Communication (CSC). National Institute of Advanced Industrial Science and Technology (AIST), Japan.
    Gros, Quentin
    Rousset, Guillaume
    Banzai, Kazuaki
    Ma, Lei
    Kitamura, Takashi
    Hagiya, Masami
    Tanabe, Yoshinori
    Yamamoto, Mitsuharu
    Model-based API Testing of Apache ZooKeeper2017In: 2017 10TH IEEE INTERNATIONAL CONFERENCE ON SOFTWARE TESTING, VERIFICATION AND VALIDATION (ICST), IEEE , 2017, p. 288-298Conference paper (Refereed)
    Abstract [en]

    Apache ZooKeeper is a distributed data storage that is highly concurrent and asynchronous due to network communication; testing such a system is very challenging. Our solution using the tool "Modbat" generates test cases for concurrent client sessions, and processes results from synchronous and asynchronous callbacks. We use an embedded model checker to compute the test oracle for non-deterministic outcomes; the oracle model evolves dynamically with each new test step. Our work has detected multiple previously unknown defects in ZooKeeper. Finally, a thorough coverage evaluation of the core classes show how code and branch coverage strongly relate to feature coverage in the model, and hence modeling effort.

  • 13. Artho, Cyrille
    et al.
    Havelund, Klaus
    Kumar, Rahul
    Yamagata, Yoriyuki
    Domain-Specific Languages with Scala2015In: Proc. 17th Int. Conf. on Formal Engineering Methods (ICFEM 2015), 2015, Vol. 9407, p. 1-16Conference paper (Refereed)
  • 14. Artho, Cyrille
    et al.
    Hayamizu, Koji
    Ramler, Rudolf
    Yamagata, Yoriyuki
    With an Open Mind: How to Write Good Models2014In: Proc. 2nd Int. Workshop on Formal Techniques for Safety-Critical Systems (FTSCS 2013), 2014, p. 3-18Conference paper (Refereed)
  • 15. Artho, Cyrille
    et al.
    Ma, Lei
    Classification of Randomly Generated Test Cases2016In: Proc. 1st Int. Workshop on Validating Software Tests (VST 2016), IEEE conference proceedings, 2016Conference paper (Refereed)
    Abstract [en]

    Random test case generation produces relatively diverse test sequences, but the validity of the test verdict is always uncertain. Because tests are generated without taking the specification and documentation into account, many tests are invalid. To understand the prevalent types of successful and invalid tests, we present a classification of 56 issues that were derived from 208 failed, randomly generated test cases. While the existing workflow successfully eliminated more than half of the tests as irrelevant, half of the remaining failed tests are false positives. We show that the new @NonNull annotation of Java 8 has the potential to eliminate most of the false positives, highlighting the importance of machine-readable documentation.

  • 16. Artho, Cyrille
    et al.
    Oiwa, Yutaka
    Suzaki, Kuniyasu
    Hagiya, Masami
    Extraction of properties in C implementations of security APIs for verification of Java applications2009In: Proc. 3rd Int. Workshop on Analysis of Security APIs, 2009Conference paper (Refereed)
  • 17. Artho, Cyrille
    et al.
    Suzaki, Kuniyasu
    Cosmo, Roberto di
    Treinen, Ralf
    Zacchiroli, Stefano
    Why Do Software Packages Conflict?2012In: Proc. 9th Working Conf. on Mining Software Repositories (MSR 2012), 2012, p. 141-150Conference paper (Refereed)
  • 18. Artho, Cyrille
    et al.
    Suzaki, Kuniyasu
    Cosmo, Roberto di
    Zacchiroli, Stefano
    Sources of Inter-package Conflicts in Debian2011In: Proc. Workshop on Logics for Component Configuration (LoCoCo 2011), 2011Conference paper (Refereed)
  • 19. Artho, Cyrille
    et al.
    Suzaki, Kuniyasu
    Hagiya, Masami
    Leungwattanakit, Watcharin
    Potter, Richard
    Platon, Eric
    Tanabe, Yoshinori
    Weitl, Franz
    Yamamoto, Mitsuharu
    Using Checkpointing and Virtualization for Fault Injection2015In: International Journal of Networking and Computing, ISSN 2185-2839, E-ISSN 2185-2847, Vol. 5, no 2, p. 347-372Article in journal (Refereed)
  • 20. Azizyan, G.
    et al.
    Magarian, M. K.
    Kajko-Mattson, Mira
    KTH, School of Information and Communication Technology (ICT), Software and Computer systems, SCS.
    Survey of agile tool usage and needs2011In: Proceedings - 2011 Agile Conference, 2011, p. 29-38Conference paper (Refereed)
    Abstract [en]

    Today little is known about what tools software companies are using to support their Agile methods and whether they are satisfied or dissatisfied with them. This is due to lack of objective surveys on the subject. The surveys that have been conducted so far are of a subjective nature and have mostly been performed by tool vendors. They are very limited in number and focus mainly on company structure and adherence to a specific Agile method rather than on tool usage and needs. For this reason many companies have difficulties to choose appropriate tools to support their Agile process. One such company is the Swedish telecommunications giant Ericsson. To account for this lack of data Ericsson commissioned us to conduct an independent survey focusing on the tool usage and needs as experienced by the Agile software community today. In this paper we report on the results of our survey. The survey covers 121 responses from 120 different companies coming from 35 different countries. Our results show that the most satisfactory tool aspect is ease of use whereas the least satisfactory one is lack of integration with other systems. Finally our results provide a list of features that are most desired by the software companies today.

  • 21.
    BARRY, Raphael
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Sustainable Building Design with Autodesk Ecotect2011Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
  • 22. Basit, K. A.
    et al.
    Matskin, Mihhail
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Software and Computer Systems, SCS (Closed 20120101).
    GUMO inspired ontology to support user experience based Citywide Mobile Learning2011In: Proc. - Int. Conf. User Sci. Eng., i-USEr, 2011, p. 195-200Conference paper (Refereed)
    Abstract [en]

    User experience has been extensively discussed in literature, yet the idea of applying it to explain and comprehend the conceptualization of Mobile Learning (ML) is relatively new. Consequently much of the existing works are mainly theoretical and they concentrate to establish and explain the relationship between ML and experience. Little has been done to apply or adopt it into practice. In contrast to the currently existing approaches, this paper presents an ontology to support Citywide Mobile Learning (CML). The ontology presented in this paper addresses three fundamental aspects of CML, namely User Model, User Experience and Places/Spaces which exist in the city. The ontology presented here not only attempts to model and translate the theoretical concepts such as user experience and Place/Spaces for citywide context for Mobile Learning, but also apply them into practice. The discussed ontology is used in our system to support Place/Space based CML.

  • 23.
    Bernhem, Kristoffer
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Brismar, Hjalmar
    KTH, School of Engineering Sciences (SCI), Applied Physics. KTH, Centres, Science for Life Laboratory, SciLifeLab. Karolinska Institutet, Sweden.
    SMLocalizer, a GPU accelerated ImageJ plugin for single molecule localization microscopy2018In: Bioinformatics, ISSN 1367-4803, E-ISSN 1367-4811, Vol. 34, no 1, p. 137-Article in journal (Refereed)
    Abstract [en]

    SMLocalizer combines the availability of ImageJ with the power of GPU processing for fast and accurate analysis of single molecule localization microscopy data. Analysis of 2D and 3D data in multiple channels is supported.

  • 24.
    Bhalsingh, Ashwini
    KTH, School of Information and Communication Technology (ICT).
    Cloud Infrastructure for Smart Devices: SmartClouds2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    On-demand resource provisioning is an important feature of cloud, which offers several benefits such as scalability, enhanced performance, low maintenance cost, elasticity, adequate storage, ubiquitous accessibility, minimum infrastructure etc. At the same time, usage of mobile phones is becoming increasingly common throughout the world. Also, these phones are coming in the market with appealing features like fast processing unit, internal and external memory up to MBs and GBs respectively, web browsing, inbuilt sensors, powerful cameras etc. This master’s thesis project proposes a novel approach of utilizing all these features of semi-autonomous mobile devices (especially smart phones) and cloud infrastructure altogether.

    The specific aim of project is to design, implement and present a framework for multi-featured smart phone on top of cloud infrastructure. Proposed framework is implemented and tested for two different communication methods known as client poll and server push. In the second phase, performance analysis of implemented framework is carried out via simulation to compare two methods of interaction and to observe server’s load. As a result, first it is found that the server-initiated communication (i.e. server push) requires 40% to 50% less times as compared to the client-initiated communication (i.e. client poll). Second, it is observed that the application server load of framework is not affected too much regarding increasing number of client’s requests.

  • 25.
    Biehl, Matthias
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Early Automated Verification of Tool Chain Design2012In: Computational Science And Its Applications - ICCSA 2012, PT IV / [ed] Murgante, B; Gervasi, O; Misra, S; Nedjah, N; Rocha, AMAC; Taniar, D; Apduhan, BO, Springer Berlin/Heidelberg, 2012, p. 40-50Conference paper (Refereed)
    Abstract [en]

    Tool chains are expected to increase the productivity of product development by providing automation and integration. If, however, the tool chain does not have the features required to support the product development process, it falls short of this expectation. Tool chains could reach their full potential if it could be ensured that the features of a tool chain are aligned with the product development process. As part of a systematic development approach for tool chains, we propose a verification method that measures the extent to which a tool chain design conforms to the product development process and identifies misalignments. The verification method can be used early in tool chain development, when it is relatively easy and cheap to perform the necessary corrections. Our verification method is automated, which allows for quick feedback and enables iterative design. We apply the proposed method on an industrial tool chain, where it is able to identify improvements to the design of the tool chain.

  • 26.
    Biehl, Matthias
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    El-Khoury, Jad
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Törngren, Martin
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    High-Level Specification and Code Generation for Service-Oriented Tool Adapters2012In: Proceedings of the International Conference on Computational Science (ICCSA2012), 2012, p. 35-42Conference paper (Refereed)
    Abstract [en]

    The development of complex systems requires tool support for the different phases of the system life cycle. To allow for an efficient development process, the involved tools need to be integrated, e.g. by exchanging tool data or providing trace ability between the data. Despite the availability of tool integration platforms and frameworks, it is labor-intensive and costly to build tool integration solutions. Industrial tool integration initiatives such as OSLC (Open Services for Lifecycle Collaboration) demand complex configurations and the adherence to integration standards. This further complicates building an integration solution. We propose an approach that uses formalized specifications to systematize tool integration and specialized code generators to automate the process of building tool adapters. We evaluate our approach with the implementation of a code generator that creates service-oriented tool adapters conforming to the OSLC industry initiative.

  • 27.
    Biehl, Matthias
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Sosa, J. D.
    Törngren, Martin
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Diaz, O.
    Efficient construction of presentation integration for web-based and desktop development tools2013In: 2013 IEEE 37th Annual Computer Software and Applications Conference Workshops (COMPSACW), New York: IEEE , 2013, p. 697-702Conference paper (Refereed)
    Abstract [en]

    The engineering of software-intensive systems is supported by a variety of development tools. While development tools are traditionally desktop tools, they are more and more complemented and replaced by web-based development tools. The resulting blend of desktop and web-based tools is difficult to integrate into a seamless tool chain, which supports product development by data, control and presentation integration. Moreover, the construction of such tool chains is a significant engineering challenge. We propose an approach for the efficient, automated construction of tool chains, which integrate both web-based and desktop development tools; and provide a proof of concept of the approach in a case study. Our approach suggests that companies can selectively take advantage of hosted web-based development tools, while maintaining a seamless flow of integration with legacy desktop tools.

  • 28. Biere, Armin
    et al.
    Seidl, Martina
    Artho, Cyrille
    Model-Based Testing for Verification Backends2013In: Proc. 7th Int. Conf. on Tests & Proofs (TAP 2013), 2013, Vol. 7942, p. 39-55Conference paper (Refereed)
  • 29. Bjuhr, O.
    et al.
    Segeljakt, K.
    Addibpour, M.
    Heiser, F.
    Lagerström, Robert
    KTH, School of Electrical Engineering (EES), Electric Power and Energy Systems.
    Software architecture decoupling at ericsson2017In: Proceedings - 2017 IEEE International Conference on Software Architecture Workshops, ICSAW 2017: Side Track Proceedings, Institute of Electrical and Electronics Engineers (IEEE), 2017, p. 259-262, article id 7958500Conference paper (Refereed)
    Abstract [en]

    In order to evaluate and increase modularity this paper combines a method for visualizing and measuring software architectures and two algorithms for decoupling. The combination is tested on a software system at Ericsson. Our analysis show that the system has one large cluster of components (18% of the system, a Core), all interacting with each other. By employing cluster and dominator analysis we suggest 19 dependencies to be removed in order to decouple the Core. Validating the analysis output with experts at Ericsson six of the suggested dependencies where deemed impossible to remove. By removing the remaining 13 dependencies Ericsson would improve the architecture of their system considerably, e.g. core size would go down to 5%.

  • 30.
    Björk, Erik
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Åkerberg, Viktor
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Data Acquisition Architecture for HVDC Grids2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The climate crisis has caused many countries around the world to invest in large amounts of renewable energy. To be able to handle the intrinsic unreliability and geographic de- pendency of many renewable energy sources, HVDC technology is considered due to its low cost when transferring electricity across great distances. Traditional AC grids are controlled with 15-minute intervals at control centers, but HVDC grids require a faster control due to more power fluctuations within the grid. The aim of this project was to propose an architecture for a gateway in a control center for an HVDC grid. The gateway was programmed in C and C++ and the data was sent using UDP packets. Testing of the gateway was done using a real-time simulation of an HVDC grid. The data was sent with intervals smaller than a second which satisfied the speed requirements for this project. A gateway like the one developed in this project can be implemented at control centers to display and process data and to improve the overall reliability of an HVDC grid. 

  • 31. Boix, E. G.
    et al.
    Haller, Philipp
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Ricci, A.
    Varela, C.
    Workshop preview of the 2015 workshop on programming based on actors, agents, and decentralized control (AGERE! 2015)2015In: SPLASH Companion 2015 - Companion Proceedings of the 2015 ACM SIGPLAN International Conference on Systems, Programming, Languages and Applications: Software for Humanity, 2015, p. 99-100Conference paper (Refereed)
    Abstract [en]

    The AGERE! workshop focuses on programming systems, languages and applications based on actors, active/concurrent objects, agents and - more generally - high-level programming paradigms promoting a mindset of decentralized control in solving problems and developing software. The workshop is designed to cover both the theory and the practice of design and programming, bringing together researchers working on models, languages and technologies, and practitioners developing real-world systems and applications.

  • 32.
    Brander, Thomas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Dakermandji, Christian
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    En jämförelse mellan databashanterare med prestandatester och stora datamängder2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company Nordicstation handles large amounts of data for Swedbank, where data is stored using the relational database Microsoft SQL Server 2012 (SQL Server). The existence of other databases designed for handling large amounts of data, makes it unclear if SQL Server is the best solution for this situation.  This degree project describes a comparison between databases using performance testing, with regard to the execution time of database queries.  The chosen databases were SQL Server, Cassandra and NuoDB. Cassandra is a column-oriented database designed for handling large amounts of data, NuoDB is a database that uses the main memory for data storage and is designed for scalability. The performance tests were executed in a virtual server environment with Windows Server 2012 R2 using an application written in Java. SQL Server was the database most suited for grouping, sorting and arithmetic operations. Cassandra had the shortest execution time for write operations while NuoDB performed best in read operations. This degree project concludes that minimizing disk operations leads to shorter execution times but the scalable solution, NuoDB, suffer severe performance losses when configured as a single-node. Nordicstation is recommended to upgrade to Microsoft SQL Server 2014, or later, because of the possibility to save tables in main memory.

  • 33.
    Brocke, Ekaterina
    et al.
    KTH, School of Computer Science and Communication (CSC), Computational Biology, CB.
    Djurfeldt, Mikael
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for High Performance Computing, PDC.
    Efficient spike communication in the MUSIC multi-simulation framework2011In: Twentieth Annual Computational Neuroscience Meeting: CNS*2011, Springer Science+Business Media B.V., 2011Conference paper (Refereed)
  • 34.
    Broman, David
    et al.
    Linköpings universitet, Institutionen för datavetenskap.
    Fritzson, Peter
    Linköpings universitet, Institutionen för datavetenskap.
    High-Order Acausal Models2009In: Simulation News Europe, ISSN 0929-2268, Vol. 19, no 1Article in journal (Refereed)
    Abstract [en]

    Current equation-based object-oriented (EOO) languages typically contain a number of fairly complex language constructs for enabling reuse of models. However, support for model transformation is still often limited to scripting solutions provided by tool implementations. In this paper we investigate the possibility of combining the well known concept of higher-order functions, used in standard functional programming languages, with acausal models. This concept, called Higher-Order Acausal Models (HOAMs), simplifies the creation of reusable model libraries and model transformations within the modeling language itself. These transformations include general model composition and recursion operations and do not require data representation/ reification of models as in metaprogramming/metamodeling. Examples within the electrical and mechanical domain are given using a small research language. However, the language concept is not limited to a particular language, and could in the future be incorporated into existing commercially available EOO-languages.

  • 35.
    Brorsson, Mats
    et al.
    Telesoft AB.
    Kruzela, Ivan
    Telesoft AB.
    Museion-reuse support system for design of service features1991Conference paper (Refereed)
    Abstract [en]

    Museion is a reuse support system integrated in a service creation environment. A number of service features have been implemented and tested on a test bed consisting of a PABX switching system and a workstation. Reuse has been applied to all phases of the software development cycle. Museion is an intelligent database system with facilities for storage, search and evaluation of reusable components. One feature of Museion is the concept of aggregates, an abstract data structure containing reusable components as well as information supporting the classification, search and retrieval of the specific components. Museion maintains links between related aggregates enabling a hypertext navigation facility. A prototype Museion consisting of a number of integrated tools has been designed and implemented. The authors discuss the usefulness of Museion and compare it with other repositories.

  • 36.
    Brorsson, Mats
    et al.
    Telesoft AB.
    Kruzela, Ivan
    Telesoft AB.
    Reuse in Telecommunication System Development1990Report (Other academic)
  • 37.
    Brown, Lars
    et al.
    KTH, School of Information and Communication Technology (ICT).
    Axelsson, Erik
    KTH, School of Information and Communication Technology (ICT).
    Use of Information-Centric Networks in Revision Control Systems2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    NetInf and CCN are two Information-Centric Network approaches which are constructed to solve limitations of today’s Internet that was developed in the 60’s. Today’s Internet requires that datum is referred by its location. This is not something the end-user is interested in, the user is only interested in securely finding the information that searched for. These approaches decouple location from data and also aim on embedding security into the information itself and to provide caching functionality directly in networks.

    The main goal of this thesis work was to show the potential advantages of using the Information-Centric approaches by implementing them into the version control system Subversion and performing experimental evaluations.

    A Subversion adaptation has successfully been developed which supports both OpenNetInf and CCNx. With a 1Mbit/s connection to the Subversion server evaluation results show that, compared to the original implementation, checkouts can be performed 13(!) times faster using OpenNetInf and 2.3 times faster using CCNx.

    This work also presents motivation for future work in the area of Information-Centric Networks and has contributed with a working application which exploits advantages of these approaches.

  • 38.
    Chen, Xiaowen
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Chen, Shuming
    Lu, Zhonghai
    KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Jantsch, Axel
    KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Hybrid distributed shared memory space in multi-core processors2011In: Journal of Software, ISSN 1796-217X, Vol. 6, no 12 SPEC. ISSUE, p. 2369-2378Article in journal (Refereed)
    Abstract [en]

    On multi-core processors, memories are preferably distributed and supporting Distributed Shared Memory (DSM) is essential for the sake of reusing huge amount of legacy code and easy programming. However, the DSM organization imports the inherent overhead of translating virtual memory addresses into physical memory addresses, resulting in negative performance. We observe that, in parallel applications, different data have different properties (private or shared). For the private data accesses, it's unnecessary to perform Virtual-to-Physical address translations. Even for the same datum, its property may be changeable in different phases of the program execution. Therefore, this paper focuses on decreasing the overhead of Virtualto- Physical address translation and hence improving the system performance by introducing hybrid DSM organization and supporting run-time partitioning according to the data property. The hybrid DSM organization aims at supporting fast and physical memory accesses for private data and maintaining a global and single virtual memory space for shared data. Based on the data property of parallel applications, the run-time partitioning supports changing the hybrid DSM organization during the program execution. It ensures fast physical memory addressing on private data and conventional virtual memory addressing on shared data, improving the performance of the entire system by reducing virtual-to-physical address translation overhead as much as possible. We formulate the run-time partitioning of hybrid DSM organization in order to analyze its performance. A real DSM based multi-core platform is also constructed. The experimental results of real applications show that the hybrid DSM organization with run-time partitioning demonstrates performance advantage over the conventional DSM counterpart. The percentage of performance improvement depends on problem size, way of data partitioning and computation/communication ratio of parallel applications, network size of the system, etc. In our experiments, the maximal improvement is 34.42%, the minimal improvement 3.68%.

  • 39.
    Chen, Ziwei
    KTH, School of Information and Communication Technology (ICT).
    Workflow Management Service based on an Event-driven Computational Cloud2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Event-driven computing paradigm, also known as trigger computing, is widely used in computer technology. Computer systems, such as database systems, introduce trigger mechanism to reduce repetitive human intervention. With the growing complexity of industrial use case requirements, independent and isolated triggers cannot fulfil the demands any more. Fortunately, an independent trigger can be triggered by the result produced by other triggered actions, and that enables the modelling of complex use cases, where the chains or graphs that consist of triggers are called workflows. Therefore, workflow construction and manipulation become a must for implementing the complex use cases. As the developing platform of this study, VISION Cloud is a computational storage system that executes small programs called storles as independent computation units in the storage. Similar to the trigger mechanism in database systems, storlets are triggered by specific events and then execute computations. As a result, one storlet can also be triggered by the result produced by other storlets, and it is called connections between storlets. Due to the growing complexity of use case requirements, an urgent demand is to have starlet workflow management supported in VISION system. Furthermore, because of the existence of connections between storlets in VISION, problems as non-termination triggering and unexpected overwriting appear as side-effects. This study develops a management service that consists of an analysis engine and a multi-level visualization interface. The analysis engine checks the connections between storlets by utilizing the technology of automatic theorem proving and deterministic finite automaton. The involved storlets and their connections are displayed in graphs via the multi-level visualization interface. Furthermore, the aforementioned connection problems are detected with graph theory algorithms. Finally, experimental results with practical use case examples demonstrate the correctness and comprehensiveness of the service. Algorithm performance and possible optimization are also discussed. They lead the way for future work to create a portable framework of event-driven workflow management services.

  • 40.
    Christensen, Henrik Iskov
    KTH, Superseded Departments, Numerical Analysis and Computer Science, NADA.
    The curse of JDL2004In: Proc. Seventh Int. Conf. Inf. Fusion, 2004, p. 528-529Conference paper (Refereed)
    Abstract [en]

    The JDL model provides a methodology for organisation of research infusion, it is however, important to recognize that it does not provide an architectural framework for design of systems, and as such there may be complex interaction between levels in the JDL model, which is not directly captured by the model. A reductionistic approach to research in which each of the layers are considered independently might be a danger of not showing the real complexity of information fusion systems.

  • 41.
    Dahlfort, Stefan
    et al.
    Ericsson Research, United States.
    Caviglia, D.
    IP-optical convergence: A complete solution2014In: Ericsson review (English ed.), ISSN 0014-0171, Vol. 91, no 1, p. 34-40Article in journal (Refereed)
    Abstract [en]

    The current SDN movement in the telecoms industry offers a much-needed solution to attain the high levels of automation that modern networks demand - for both IP and optical systems. In parallel, and to some extent related to this, service providers are moving away from the independent operation of IP and optical transport toward a converged approach, with joint operation.

  • 42.
    Davies, Guy
    et al.
    KTH, School of Information and Communication Technology (ICT), Computer and Systems Sciences, DSV.
    Ekenberg, Love
    KTH, School of Information and Communication Technology (ICT), Computer and Systems Sciences, DSV.
    Some observations on elusion, enrichment and domination2008Conference paper (Refereed)
    Abstract [en]

    Conceptual schemata each representing some component of a system in the making, can be integrated in a variety of ways. Herein, we explore some fundamental notions of this. More particularly, we investigate some ways in which integration through correspondence assertions affects the interrelationship of two component schemata. One of the consequences of combining schemata is the appearance of events, for the united schema, that allow spurious transitions between models, transitions that would not have been possible in one of the original schemata. Much previous work has focussed on dominance with regard to preservation of information capacity as a primary integration criterion. However, even though it is desirable that the information capacity of a combined schema dominate one or both of its constituent schemata, we here discuss some aspects of why domination based on information capacity is insufficient for the integration to be semantically satisfactory.

  • 43. Dietrich, P.
    et al.
    Kretzschmar, F.
    Miassoedov, A.
    Class, A.
    Villanueva, Walter
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Power Safety.
    Bechta, Sevostian
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Power Safety.
    Extension of the MELCOR code for analysis of late in-vessel phase of a severe accident2015In: IYCE 2015 - Proceedings: 2015 5th International Youth Conference on Energy, IEEE conference proceedings, 2015Conference paper (Refereed)
    Abstract [en]

    The simulation of severe accidents in nuclear power plants with system codes is a powerful tool to improve the safety measures to prevent severe accidents. The further development of severe accident codes is part of current research. MELCOR, as the leading nuclear safety code, provides the possibility to be coupled to other codes. A detailed knowledge of this coupling interface is necessary to use this possibility. Therefore, the software tool DINAMO, which contains the coupling routines and an interface to communicate with other programs, was developed. Using DINAMO it is possible to utilize new models for specific phenomena in MELCOR. In the present work the Phase-Change Effective Convectivity Model was coupled using the CFD-software OpenFOAM and DINAMO to MELCOR to improve the prediction of molten core material in the lower plenum of a reactor pressure vessel. The simulation results were compared to the experimental findings of the LIVE-facility.

  • 44.
    Doroshenko, Anatoly
    et al.
    Institute of Software Systems, National Academy of Sciences of Ukraine, Kiev 252187, Ukraine.
    Thorelli, Lars-Erik
    KTH, Superseded Departments, Teleinformatics.
    Vlassov, Vladimir
    KTH, Superseded Departments, Teleinformatics.
    Coordination models and facilities could be parallel software accelerators1999In: HIGH-PERFORMANCE COMPUTING AND NETWORKING, PROCEEDINGS, Berlin: Springer Berlin/Heidelberg, 1999, p. 1219-1222Conference paper (Refereed)
    Abstract [en]

     A  new  coordination  model  is  constructed  for  distributed shared  memory parallel programs.  It  exploits typing of shared resources and  formal specification of a  priori known  synchronization constraints.

  • 45.
    Ebri Mars, David
    et al.
    KTH, School of Electrical Engineering (EES).
    Wu, Hanwei
    KTH, School of Electrical Engineering (EES), Communication Theory.
    Li, Haopeng
    KTH, School of Electrical Engineering (EES).
    Flierl, Markus
    KTH, School of Electrical Engineering (EES), Communication Theory.
    GEOMETRY-BASED RANKING FOR MOBILE 3D VISUAL SEARCH USING HIERARCHICALLY STRUCTURED MULTI-VIEW FEATURES2015In: 2015 IEEE INTERNATIONAL CONFERENCE ON IMAGE PROCESSING (ICIP), IEEE Computer Society, 2015, p. 3077-3081Conference paper (Refereed)
    Abstract [en]

    This paper proposes geometry-based ranking for mobile 3D visual search. It utilizes the underlying geometry of the 3D objects as well as the appearance to improve the ranking results. A double hierarchy has been embedded in the data structure, namely the hierarchically structured multi-view features for each object and a tree hierarchy from multi-view vocabulary trees. As the 3D geometry information is incorporated in the multi-view vocabulary tree, it allows us to evaluate the consistency of the 3D geometry at low computational complexity. Thus, a cost function is proposed for object ranking using geometric consistency. With that, we devise an iterative algorithm that accomplishes 3D geometry-based ranking. The experimental results show that our 3D geometry-based ranking improves the recall-datarate performance as well as the subjective ranking results for mobile 3D visual search.

  • 46.
    Ekenberg, Love
    KTH, School of Information and Communication Technology (ICT), Computer and Systems Sciences, DSV.
    A gentle introduction to system verification2005In: New trends in software methodologies, tools and techniques, Amsterdam: IOS Press, 2005, p. 173-193Conference paper (Refereed)
    Abstract [en]

    Verification is an important instrument in the analysis of systems. Roughly, this means that requirements and designs are analyzed formally to determine their relationships. Various candidates for formalizing system development and integration have been proposed. However, a major obstacle is that these introduce non-standard objects and formalisms, leading to severe confusion. This is because these models often are unnecessarily complicated with several disadvantages regarding semantics as well as complexity. While avoiding the mathematical details as far as possible, we present some basic verification ideas using a simple language Such as predicate logic and demonstrate how this can be used for defining and analyzing static and dynamic requirement fulfillment by designs as well as for detecting conflicts. The formalities can be found in the appendix.

  • 47.
    Eriksson, John
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Comparing message-oriented middleware for financial assets trading2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many different message-oriented middlewares (MOM) exist today on the market. With different underlying designs, purposes and features, it is not easy to make the right choice of MOM for your system. The IT company Nordicstation is in such a situation where they need to make a choice of MOM. They currently own a system called Sharelock which generates reports about violations of financial assets trad- ing. They wish to make the process of generating a report more asynchronous by using a MOM and they have a couple of requirements.

    This thesis was carried out with the purpose of finding the most suitable products for the system in mind, compare their features, performance, licenses and ease-of- use. This was accomplished by analysing their installation process, monitoring in- terfaces, documentation on their websites and performance in a simple throughput test.

    The results showed that RabbitMQ was the strongest candidate. It had good per- formance, an attractive web interface for monitoring, an easy installation and it also offered commercial support. Apache Artemis was also found to be an attractive choice but it did not have a web interface which made it hard to manage the system. 

  • 48.
    Fritzson, Peter
    et al.
    Linköpings universitet, Institutionen för datavetenskap.
    Pop, Adrian
    Linköpings universitet, Institutionen för datavetenskap.
    Broman, David
    Linköpings universitet, Institutionen för datavetenskap.
    Aronsson, Peter
    Linköpings universitet, Institutionen för datavetenskap.
    Formal Semantics Based Translator Generation and Tool Development in Practice2009In: Proceedings of  20th Australian Software Engineering Conference (ASWEC 2009), IEEE Computer Society, 2009, p. 256-266Conference paper (Refereed)
    Abstract [en]

    In this paper we report on a long-term research effort to develop and use efficient language implementation generators in practice. The generator is applied to a number of different languages, some of which are used for projects in industry. The used formal specification style is operational semantics, primarily in the form called natural semantics, represented and supported by a meta-language and tool called the relational meta language (RML), which can generate efficient implementations in C, on par with hand-implemented code. Generating implementations from formal specifications are assumed to give advantages such as: high level descriptions, higher degree of correctness, and consistency between specification and implementation. To what extent can this be realized in practice? Does it scale to large language implementations? To answer some of these questions we have developed specifications of a range of languages: imperative, functional, object-oriented (Java), and equation-based (Modelica). The size of specifications range from half a page to large specifications of 60 000 lines. It turns out to be possible to generate efficient compilers, also for large languages. However, the performance of the generator tool and the user support of the development environment become increasingly important for large specifications. To satisfy such user needs the speed of the generator was increased a factor of ten to reduce turn-around time, and an Eclipse plug-in including a debugger were developed. For very large specifications, the structuring and modularity of the specification itself also become essential for performance and maintainability.

  • 49. Gadia, Saurabh
    et al.
    Artho, Cyrille
    KTH. National Institute of Advanced Industrial Science and Technology, Japa.
    Bloom, Gedare
    Verifying Nested Lock Priority Inheritance in RTEMS with Java Pathfinder2016In: Proc. 18th Int. Conf. on Formal Engineering Methods (ICFEM 2016), Springer, 2016, Vol. 10009, p. 417-432Conference paper (Refereed)
    Abstract [en]

    Scheduling and synchronization algorithms for uniprocessor real-time systems benefit from the rich theory of schedulability analysis, and yet translating these algorithms to practical implementations can be challenging. This paper presents a Java model of the priority inheritance protocol for mutual exclusion, as implemented in the RTEMS open-source real-time operating system. We verified this model using Java Pathfinder to detect potential data races, deadlocks, and priority inversions. JPF detected a known bug in the RTEMS implementation, which we modified along with the Java model. Verification of the modified model showed the absence of data races, deadlocks, and established nine protocol-specific correctness properties.

    The full text will be freely available from 2018-10-15 09:02
  • 50.
    Galdo, Carlos
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    Chavez, Teddy
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    Prototyputveckling för skalbar motor med förståelse för naturligt språk2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Natural Language Understanding is a field that is part of Natural Language Processing. Big improvements have been made in the broad field of Natural Language Understanding during the past two decades. One big contribution to this is improvement is Neural Networks, a mathematical model inspired by biological brains. Natural Language Understanding is used in fields that require deeper understanding by applications. Google translate, Google search engine and grammar/spelling check are some examples of applications requiring deeper understanding.

    Thing Launcher is an application developed by A Great Thing AB. Thing Launcher is an application capable of managing other applications with different parameters. Some examples of parameters the user can use are geographic position and time. The user can as an example control what song will be played when you get home or order an Uber when you arrive to a certain destination. It is possible to control Thing Launcher today by text input. A Great Thing AB needs help developing a prototype capable of understanding text input and speech. The meaning of scalable is that it should be possible to develop, add functions and applications with as little impact as possible on up time and performance of the service. A comparison of suitable algorithms, tools and frameworks has been made in this thesis in order research what it takes to develop a scalable engine with the natural language understanding and then build a prototype from this gathered information. A theoretical comparison was made between Hidden Markov Models and Neural Networks. The results showed that Neural Networks are superior in the field of natural language understanding. The tests made in this thesis indicated that high accuracy could be achieved using neural networks. TensorFlow framework was chosen because it has many different types of neural network implemented in C/C++ ready to be used with Python and alsoand for the wide compatibility with mobile devices.  The prototype should be able to identify voice commands. The prototype has two important components called Command tagger, which is going to identify which application the user wants to control and NER tagger, which is the going to identify what the user wants to do. To calculate the accuracy, two types of tests, one for each component, was executed several times to calculate how often the components guessed right after each training iteration. Each training iteration consisted of giving the components thousands of sentences to guess and giving them feedback by then letting them know the right answers. With the help of feedback, the components were molded to act right in situations like the training. The tests after the training process resulted with the Command tagger guessing right 94% of the time and the NER tagger guessing right 96% of the time.

    The built-in software in Android was used for speech recognition. This is a function that converts sound waves to text. A server-based solution with REST interface was developed to make the engine scalability.

    This thesis resulted with a working prototype that can be used to further developed into a scalable engine.

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