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  • 301.
    Berhane, Welderufael Tesfay
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Aleksy, Markus
    ABB Corporate Research.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Lehtola, Marko
    ABB Corporate Research.
    Mobile computing application for industrial field service engineering: a case for ABB service engineers2013In: Proceedings of the 38th IEEE Conference on Local Computer Networks Workshops (LCN Workshops): 7th IEEE Workshop On User MObility and VEhicular Networks / [ed] Damla Turgut; Nils Aschenbruck; Jens Tölle, Piscataway, NJ: IEEE Computer Society Press , 2013, p. 188-193Conference paper (Refereed)
    Abstract [en]

    The increasing digitalization of our daily lives is gaining a new momentum recently in what is called the post- desktop era of computing. This wide spread in digitalization is made possible by the introduction of handy devices specifically of mobile phones, laptop computers, smartphones, and tablets. This new trend in shaping up technological advancement presents new opportunities for mobile information presentation, processing, and synthesis in different spheres of application such as providing industrial field services engineering support. Industrial field service engineers execute sets of work orders on daily basis plans. These work order executions demand the availability of digital information anywhere anytime to process them faster. This paper presents a scenario where the newly emerging Smartphone features such as augmented reality, audio/video processing, and near field communication sensing can be used to develop a prototype that supports industrial field service engineers in the contemporary field service engineering taskforces. It employs real world use-cases and carrying out quantitative prototype usability test analysis.

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  • 302.
    Bernsmed, Karin
    et al.
    SINTEF Digital, Trondheim, Norway.
    Bour, Guillaume
    SINTEF Digital, Trondheim, Norway.
    Lundgren, Martin
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Digital Services and Systems.
    Bergström, Erik
    Jönköping University, Jönköping, Sweden.
    An evaluation of practitioners’ perceptions of a security risk assessment methodology in air traffic management projects2022In: Journal of Air Transport Management, ISSN 0969-6997, E-ISSN 1873-2089, Vol. 102, article id 102223Article in journal (Refereed)
    Abstract [en]

    Cyber security is a key enabler for safe Air Traffic Management (ATM). This paper presents results from an empirical study, in which we have investigated and evaluated the use of the Security Risk Assessment Methodology for SESAR (SecRAM) in European ATM research and development projects. The study was performed with the intention to find and document common issues and aspects that could be improved in the methodology. The results from the study reveal that while most of the practitioners had a positive perception of the methodology itself, they were less satisfied with the process of applying it in their projects. Based on the results, we provide a number of recommendations, which aim to improve the security risk assessment process in the ATM domain.

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  • 303.
    Bezerra, Nibia Souza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Ferreira Maciel, Tarcisio
    Federal University of Ceará.
    M. Lima, Francisco Rafael
    Federal University of Ceará.
    Sousa Jr., Vicente A.
    Federal University of Rio Grande do Norte.
    Interference Aware Resource Allocation with QoS Guarantees in OFDMA/SC-FDMA2018In: Journal of Communication and Information Systems, ISSN 1980-6604, Vol. 33, no 1, p. 124-128Article in journal (Refereed)
    Abstract [en]

    Efficient Radio Resource Allocation (RRA) is of utmost importance for achieving maximum capacity in mobile networks. However, the performance assessment should take into account the main constraints of these networks. This letter presents important enhancements to RRA algorithms proposed in [1]. Prior work [1] ignores some important system constraints such as the impact of inter-cell interference and granularity of frequency allocation blocks. Here we show the performance degradation when these system constraints are assumed on the algorithms in [1] as well as propose some improvements on these algorithms in order to achieve better performance.

  • 304.
    Bezerra, Nibia Souza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Wang, Min
    Network Architecture and Protocols Research, Ericsson .
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Nordberg, Mats
    Network Architecture and Protocols Research, Ericsson .
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    RACH performance in massive machine-type communications access scenario2018Conference paper (Refereed)
    Abstract [en]

    With the increasing number of devices performing Machine-Type Communications (MTC), mobile networks are expected to encounter a high load of burst transmissions. One bottleneck in such cases is the Random Access Channel (RACH) procedure, which is responsible for the attachment of devices, among other things. In this paper, we performed a rich-parameter based simulation on RACH to identify the procedure bottlenecks. A finding from the studied scenarios is that the Physical Downlink Control Channel (PDCCH) capacity for the grant allocation is the main limitation for the RACH capacity rather than the number of Physical Random Access Channel (PRACH) preambles. Guided by our simulation results, we proposed improvements to the RACH procedure and to PDCCH.

  • 305.
    Bezerra, Nibia Souza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Saguna, Saguna
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    de Sousa Jr., Vicente A.
    Communication Engineering Department (DCO), Federal University of Rio Grande do Norte (UFRN), Rio Grande do Norte, Brazil.
    Propagation Model Evaluation for LoRaWAN: Planning Tool Versus Real Case Scenario2019In: IEEE 5th World Forum on Internet of Things, IEEE, 2019Conference paper (Refereed)
    Abstract [en]

    LoRa has emerged as a prominent technology for the Internet of Things (IoT), with LoRa Wide Area Network (LoRaWAN) emerging as a suitable connection solution for smartthings. The choice of the best location for the installation of gateways, as well as a robust network server configuration, are key to the deployment of a LoRaWAN. In this paper, we present an evaluation of Received Signal Strength Indication (RSSI) values collected from the real-life LoRaWAN deployed in Skellefteå, Sweden, when compared with the values calculatedby a Radio Frequency (RF) planning tool for the Irregular Terrain Model (ITM), Irregular Terrain with Obstructions Model (ITWOM) and Okumura-Hata propagation models. Five sensors are configured and deployed along a wooden bridge, with different Spreading Factors (SFs), such as SF 7, 10 and 12. Our results show that the RSSI values calculated using the RF planning tool for ITWOM are closest to the values obtained from the real-life LoRaWAN. Moreover, we also show evidence that the choice of a propagation model in an RF planning tool has to be made with care, mainly due to the terrain conditions of the area where the network and the sensors are deployed.

  • 306.
    Bezerra, Nibia Souza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Saguna, Saguna
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    de Sousa Jr., Vicente A.
    Federal University of Rio Grande do Norte (UFRN).
    Temperature Impact in LoRaWAN: A Case Study in Northern Sweden2019In: Sensors, E-ISSN 1424-8220, Vol. 19, no 20, article id 4414Article in journal (Refereed)
    Abstract [en]

    LoRaWAN has become popular as an IoT enabler. The low cost, ease of installation and the capacity of fine-tuning the parameters make this network a suitable candidate for the deployment of smart cities. In northern Sweden, in the smart region of Skellefteå, we have deployed a LoRaWAN to enable IoT applications to assist the lives of citizens. As Skellefteå has a subarctic climate, we investigate how the extreme changes in the weather happening during a year affect a real LoRaWAN deployment in terms of SNR, RSSI and the use of SF when ADR is enabled. Additionally, we evaluate two propagation models (Okumura-Hata and ITM) and verify if any of those models fit the measurements obtained from our real-life network. Our results regarding the weather impact show that cold weather improves the SNR while warm weather makes the sensors select lower SFs, to minimize the time-on-air. Regarding the tested propagation models, Okumura-Hata has the best fit to our data, while ITM tends to overestimate the RSSI values.

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  • 307.
    Bhat, Soha Maqbool
    et al.
    Department of Electrical and Electronics Engineering, Mahindra University, Hyderabad, 500043, India.
    Ahmed, Suhaib
    Department of Electronics and Communication Engineering, Baba Ghulam Shah Badshah University, Rajouri 185234, India.
    Bahar, Ali Newaz
    Department of Information and Communication Technology (ICT), Mawlana Bhashani Science and Technology University, Tangail, 1902, Bangladesh; Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, SK S7N5A9, Canada.
    Wahid, Khan A.
    Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, SK S7N5A9, Canada.
    Otsuki, Akira
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering. Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Diagonal Las Torres 2640, Peñalolén, Santiago, 7941169, Chile; Neutron Beam Technology Team, RIKEN Center for Advanced Photonics, RIKEN, Wako, 351-0198, Japan.
    Singh, Pooran
    Department of Electrical and Electronics Engineering, Mahindra University, Hyderabad, 500043, India.
    Design of Cost-Efficient SRAM Cell in Quantum Dot Cellular Automata Technology2023In: Electronics, E-ISSN 2079-9292, Vol. 12, no 2, article id 367Article in journal (Refereed)
    Abstract [en]

    SRAM or Static Random-Access Memory is the most vital memory technology. SRAM is fast and robust but faces design challenges in nanoscale CMOS such as high leakage, power consumption, and reliability. Quantum-dot Cellular Automata (QCA) is the alternative technology that can be used to address the challenges of conventional SRAM. In this paper, a cost-efficient single layer SRAM cell has been proposed in QCA. The design has 39 cells with a latency of 1.5 clock cycles and achieves an overall improvement in cell count, area, latency, and QCA cost compared to the reported designs. It can therefore be used to design nanoscale memory structures of higher order.

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  • 308.
    Bicaku, Ani
    et al.
    University of Applied Sciences Burgenland.
    Bauer, Elisabeth
    University of Applied Sciences Burgenland.
    Schluga, Oliver
    University of Applied Sciences Burgenland.
    Maksuti, Silia
    University of Applied Sciences Burgenland.
    Hofbauer, David
    University of Applied Sciences Burgenland.
    Ivkic, Igor
    University of Applied Sciences Burgenland.
    Tauber, Markus
    University of Applied Sciences Burgenland.
    Towards a security baseline for IaaS-cloud back-ends in Industry 4.02017Conference paper (Refereed)
    Abstract [en]

    The popularity of cloud based Infrastructure-as-aService (IaaS) solutions is becoming increasingly popular. However, since IaaS providers and customers interact in a flexible and scalable environment, security remains a serious concern. To handle such security issues, defining a set of security parameters in the service level agreements (SLA) between both, IaaS provider and customer, is of utmost importance. In this paper, the European Network and Information Security Agency (ENISA) guidelines are evaluated to extract a set of security parameters for IaaS. Furthermore, the level of applicability and implementation of this set is used to assess popular industrial and open-source IaaS cloud platforms, respectively VMware and OpenStack. Both platforms provide private clouds, used as backend infrastructures in Industry 4.0 application scenarios. The results serve as initial work to identify a security baseline and research needs for creating secure cloud environments for Industry 4.0

  • 309.
    Bikis, Tilemachos
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    SAFe and DevSecOps in Governmental Organizations: A case study for benefits and challenges2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis conducted a case study in order to identify and analyze the benefits andthe challenges of SAFe and DevSecOps adoption in governmental organizations. Ithas been identified that governmental organizations are falling behind the market inrespects of SAFe and DevSecOps adoption while in the same time not much researchhas been done in the specific market area, aim of this study is to provide moreinsights in the subject. In particular this research is trying to answer the followingquestions, how are the Governmental Organizations benefit from the DevSecOps andSAFe adoption and why is the adoption of DevSecOps and SAFe challenging forGovernmental Organizations.From the conducted case study identified clear benefits on the SAFe and DevSecOpsadoption for Governmental Organizations which are summed up to the bettermanagement of existing demand, increased transparency and compliance, bettersecurity assurance. At the same time challenges also surfaced in the scope of thestudy related with organization’s culture, administrative challenges related withorganization processes and security ones. Most of the results are in line with previousresearch on the broader market though specific challenges observed in correlationwith governmental organizations in particular.

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  • 310.
    Bilal, Mohd
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    A Heuristic Search Algorithm for Asteroid Tour Missions2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Since the discovery of Ceres, asteroids have been of immense scientific interest and intrigue. They hold answers to many of the fundamental questionsabout the formation and evolution of the Solar System. Therefore, a missionsurveying the asteroid belt with close encounter of carefully chosen asteroidswould be of immense scientific benefit. The trajectory of such an asteroidtour mission needs to be designed such that asteroids of a wide range ofcompositions and sizes are encountered; all with an extremely limited ∆Vbudget.This thesis presents a novel heuristic algorithm to optimize trajectoriesfor an asteroid tour mission with close range flybys (≤ 1000 km). The coresearch algorithm efficiently decouples combinatorial (i.e. choosing the asteroids to flyby)and continuous optimization (i.e. optimizing critical maneuversand events) of what is essentially a mixed integer programming problem.Additionally, different methods to generate a healthy initial population forthe combinatorial optimization are presented.The algorithm is used to generate a set of 1800 feasible trajectories withina 2029+ launch frame. A statistical analysis of these set of trajectories isperformed and important metrics for the search are set based on the statistics.Trajectories allowing flybys to prominent families of asteroids like Flora andNysa with ∆V as low as 4.99 km/s are obtained.Two modified implementations of the algorithm are presented. In a firstiteration, a large sample of trajectories is generated with a limited numberof encounters to the most scientifically interesting targets. While, a posteriori, trajectories are filled in with as many small targets as possible. Thisis achieved in two different ways, namely single step extension and multiplestep extension. The former fills in the trajectories with small targets in onestep, while the latter optimizes the trajectory by filling in with one asteroid per step. The thesis also presents detection of asteroids for successfullyperforming flybys. A photometric filter is developed which prunes out badlyilluminated asteroids. The best trajectory is found to perform well againstthis filter such that nine out of the ten planned flybys are feasible.

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  • 311.
    Birk, Wolfgang
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Eliasson, Jens
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Lindgren, Per
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Osipov, Evgeny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Riliskis, Laurynas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Road surface networks technology enablers for enhanced ITS2010In: 2010 IEEE Vehicular Networking Conference, VNC 2010: Jersey City, NJ ; 13-15 Dec 2010, Piscataway, NJ: IEEE Communications Society, 2010, p. 152-159Conference paper (Refereed)
    Abstract [en]

    The increased need for mobility has led to transportation problems like congestion, accidents and pollution. In order to provide safe and efficient transport systems great efforts are currently being put into developing Intelligent Transport Systems (ITS) and cooperative systems. In this paper we extend proposed solutions with autonomous on-road sensors and actuators forming a wireless Road Surface Network (RSN). We present the RSN architecture and design methodology and demonstrate its applicability to queue-end detection. For the use case we discuss the requirements and technological solutions to sensor technology, data processing and communication. In particular the MAC protocol is detailed and its performance assessed through theoretical verification. The RSN architecture is shown to offer a scalable solution, where increased node density offers more precise sensing as well as increased redundancy for safety critical applications. The use-case demonstrates that RSN solutions may be deployed as standalone systems potentially integrated into current and future ITS. RSN may provide both easily deployable and cost effective alternatives to traditional ITS (with a direct impact independent of penetration rate of other ITS infrastructures - i.e., smart vehicles, safe spots etc.) as well as provide fine grain sensory information directly from the road surface to back-end and cooperative systems, thus enabling a wide range of ITS applications beyond current state of the art.

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  • 312.
    Birk, Wolfgang
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Osipov, Evgeny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    On the design of cooperative road infrastructure systems2008In: Reglermöte 2008: proceedings / [ed] Thomas Gustafsson; Wolfgang Birk; Andreas Johansson, Luleå: Luleå tekniska universitet, 2008Conference paper (Other academic)
    Abstract [en]

    This paper discusses the design of cooperative road infrastructure systems for infrastructure-based driving support functions. The background of such systems is mapped out and it is shown that there is a need for a cross disciplinary approach. Using an example of a support function, namely the overtaking support, it is shown that such a system is feasible. The different challenges and technological problems that are identified are given and the future work is indicated.

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  • 313.
    Birk, Wolfgang
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Osipov, Evgeny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Eliasson, Jens
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    iRoad - cooperative road infrastructure systems for driver support2009In: 16th World Congress and Exhibition on Intelligent Transport Systems 2009: 16th ITS World Congress ; Stockholm, Sweden, 21 - 25 September 2009, Red Hook: Curran Associates, Inc., 2009Conference paper (Refereed)
    Abstract [en]

    This paper discusses the design and implementation of a cooperative road infrastructure systems, which uses an intelligent road surface. Using an overtaking assist feature as an example it is shown how such a feature can be designed and implemented on a road infrastructure and integrated with drivers and passengers using IMS. The feasibility of this feature is assessed from a functional and communication perspective. Moreover, first results from real-life tests on the Swedish highway E4 are presented which motivate the next research and development steps.

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  • 314.
    Birk, Wolfgang
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Osipov, Evgeny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Riliskis, Laurynas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Hesler, Alban
    NEC.
    Modular design and performance ranking of communication protocols2009Report (Other academic)
    Abstract [en]

    In this deliverable we present a systematic approach towards designing modularized protocols and rank a contribution of their components to the overall system performance. In the nutshell, this approach is based onthree steps: 1.) identifying adjustable parameters in existing protocols, 2.) ranking their influence on the system-level performance metrics and 3.) defining protocol modules exposing the parameters of the highest rank. To this end we present the definition of the components for constructing MAC protocols based on ranking of the impact of adjustable parameters on the overall system performance. We also overview a ranking method for functional blocks of protocols on the routing layer.

  • 315.
    Bishnoi, Sudha
    et al.
    Department of Mathematics and Statistics, Chaudhary Charan Singh Haryana Agricultural University, Hisar 125004, Haryana, India.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Khan, Mujahid
    Agricultural Research Station, Sri Karan Narendra Agriculture University, Jobner 332301, Rajasthan, India.
    Heddam, Salim
    Agronomy Department, Faculty of Science, Hydraulics Division University, 20 Août 1955, Route El Hadaik, BP 26, Skikda 21024, Algeria.
    Malik, Anurag
    Regional Research Station, Punjab Agricultural University, Bathinda 151001, Punjab, India.
    Classification of Cotton Genotypes with Mixed Continuous and Categorical Variables: Application of Machine Learning Models2022In: Sustainability, E-ISSN 2071-1050, Vol. 14, no 20, article id 13685Article in journal (Refereed)
    Abstract [en]

    Mixed data is a combination of continuous and categorical variables and occurs frequently in fields such as agriculture, remote sensing, biology, medical science, marketing, etc., but only limited work has been done with this type of data. In this study, data on continuous and categorical characters of 452 genotypes of cotton (Gossypium hirsutum) were obtained from an experiment conducted by the Central Institute of Cotton Research (CICR), Sirsa, Haryana (India) during the Kharif season of the year 2018–2019. The machine learning (ML) classifiers/models, namely k-nearest neighbor (KNN), Classification and Regression Tree (CART), C4.5, Naïve Bayes, random forest (RF), bagging, and boosting were considered for cotton genotypes classification. The performance of these ML classifiers was compared to each other along with the linear discriminant analysis (LDA) and logistic regression. The holdout method was used for cross-validation with an 80:20 ratio of training and testing data. The results of the appraisal based on hold-out cross-validation showed that the RF and AdaBoost performed very well, having only two misclassifications with the same accuracy of 97.26% and the error rate of 2.74%. The LDA classifier performed the worst in terms of accuracy, with nine misclassifications. The other performance measures, namely sensitivity, specificity, precision, F1 score, and G-mean, were all together used to find out the best ML classifier among all those considered. Moreover, the RF and AdaBoost algorithms had the highest value of all the performance measures, with 96.97% sensitivity and 97.50% specificity. Thus, these models were found to be the best in classifying the low- and high-yielding cotton genotypes.

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  • 316.
    Biswas, Munmun
    et al.
    BGC Trust University Bangladesh,Department of Computer Science and Engineering,Bidyanagar, Chandanaish,Bangladesh.
    Chowdury, Mohammad Salah Uddin
    BGC Trust University Bangladesh,Department of Computer Science and Engineering,Bidyanagar, Chandanaish,Bangladesh.
    Nahar, Nazmun
    BGC Trust University Bangladesh,Department of Computer Science and Engineering,Bidyanagar, Chandanaish,Bangladesh.
    Hossain, Mohammad Shahadat
    University of Chittagong University,Department of Computer Science and Engineering,Bangladesh,4331.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A Belief Rule Base Expert System for staging Non-Small Cell Lung Cancer under Uncertainty2019In: BECITHCON 2019: 2019 IEEE International Conference on Biomedical Engineering, Computer and Information Technology for Health (BECITHCON), IEEE, 2019, p. 47-52Conference paper (Other academic)
    Abstract [en]

    Non small cell Lung cancer (NSCLC) is one of the most well-known types of Lung cancer which is reason for cancer related demise in Bangladesh. The early detection stage of NSCLC is required for improving the survival rate by taking proper decision for surgery and radiotherapy. The most common factors for staging NSCLC are age, tumor size, lymph node distance, Metastasis and Co morbidity. Moreover, physicians' diagnosis is unable to give more reliable outcome due to some uncertainty such as ignorance, incompleteness, vagueness, randomness, imprecision. Belief Rule Base Expert System (BRBES) is fit to deal with above mentioned uncertainty by applying both Belief Rule base and Evidential Reasoning approach. Therefore, this paper represents the architecture, development and interface for staging NSCLC by incorporating belief rule base as well as evidential reasoning with the capability of handling uncertainty. At last, a comparative analysis is added which indicate that the outcomes of proposed expert system is more reliable and efficient than the outcomes generated from traditional human expert as well as Support Vector Machine (SVM) or Fuzzy Rule Base Expert System (FRBES).

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  • 317.
    Bitar, Hadi
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Jakobsson, Björn
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    GDPR: Securing Personal Data in Compliance with new EU-Regulations2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    New privacy regulations bring new challenges to organizations that are handling and processing personal data regarding persons within the EU. These challenges come mainly in the form of policies and procedures but also with some opportunities to use technology often used in other sectors to solve problems. In this thesis, we look at the new General Data Protection Regulation (GDPR) in the EU that comes into full effect in May of 2018, we analyze what some of the requirements of the regulation means for the industry of processing personal data, and we look at the possible solution of using hardware security modules (HSMs) to reach compliance with the regulation. We also conduct an empirical study using the Delphi method to ask security professionals what they think the most important aspects of securing personal data, and put that data in relation to the identified compliance requirements of the GDPR to see what organizations should focus on in their quest for compliance with the new regulation. We found that a successful implementation of HSMs based on industry standards and best practices address four of the 35 identified GDPR compliance requirements, mainly the aspects concerning compliance with anonymization through encryption, and access control. We also deduced that the most important aspect of securing personal data according to the experts of the Delphi study is access control followed by data inventory and classification. 

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  • 318. Bittencourt, Roberto Almeida
    et al.
    Carr, David
    Luleå University of Technology.
    A method for asynchronous web-based lecture delivery2001In: Impact on engineering and science education: conference proceedings / FIE 2001, 31st Annual Frontiers in Education Conference, IEEE Communications Society, 2001Conference paper (Refereed)
    Abstract [en]

    Computer-based distance education has been growing enormously in recent years due to advances in key technologies: telecommunications, computer technology, graphical user interfaces, and the Internet. Distance education materials can be presented either synchronously, creating the illusion of a classroom on the computer, or asynchronously, allowing the students access-on-demand. We describe the development of a system to solve part of the asynchronous education problem - delivery of pre-recorded multimedia lectures via a web browser. We built a demonstration system using off-the-shelf technology making it possible to make presentations using commercial tools and to display them on standard systems. We designed the system with lectures composed of "slides" accompanied by audio commentary. These presentations can be delivered via lowspeed modem links - an important consideration in places without a well-developed infrastructure. We also believe that computer-based education is often so complicated to use that operation interferes with education. In order to avoid this, we evaluated a prototype system to obtain feedback about difficulties in operation and to correct them.

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  • 319.
    Björk, Hanna
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Johnsson, Gustav
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Navigation i komplexa miljöer med hjälp av digitala tjänster och IoT2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Research and implementation of use when it comes to outdoor navigation and GPS systems have come quite far compared to their indoor alternatives. Pedestrian friendly wayfinding solutions for indoor use are still lagging behind, and even more so when it comes to recommendations on implementation of best practice.

    One of our goals during the research process was aimed at finding the most adequate ways of conveying wayfinding solutions to end-users in different situations. In order to perform this task, we used a benchmarking process on a selection of wayfinding alternatives. The goal of this process have been focused on finding out which solutions are available at this moment, what they offer the users in terms of wayfinding support, and where issues might arise based on cognitive user theory, wayfinding best practice and technological limitations concerning mobile devices or different digital platforms.

    During our research we found that there are several different solutions that are available for implementation, but that they all come with their own specific strengths and limitations on both the technological side and for the end-users concerning usability.

    The result of our research has been a collection of qualitative data, and recommendations concerning digital and user limitations connected to our specific case. However, the result of this research should not be limited to our case alone, but rather as a reference point for organizations or developers that wish to implement indoor solutions for users, or for future research within the area of indoor navigation and wayfinding.

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  • 320.
    Björklund, Axel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    GNSS Safety and Handling2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Satellite navigation (such as GPS) has become widely successful and is used by billions of users daily. Accuratepositioning and timing has a wide range of applications and is increasingly being integrated in safety criticalsystems such as autonomous operations, traffic management, navigation for airplanes and other vehicles. Thesecurity and vulnerabilities of satellite navigation is however often not considered in the same way as for exampledata security, even though the high efficacy of spoofing with off-the-self software-defined radio (SDR) has beendemonstrated repeatedly. The lack of concern comes partially from the lack of options as satellite navigationauthentication has not previously existed in the civil domain.This work benchmarks the anti-spoofing and signal level measurements of commercial receivers in both simulatedand real-world scenarios and implements additional anti-spoofing measures. The additional anti-spoofingmeasures are implemented using no additional information than what the receiver should already have accessto in any modern commercial vehicle. Upcoming EU regulation 2021/1228 for vehicles used in internationaltransport will also mandate the use of these three anti-spoofing measures by August 2023. Here receiver time isverified by the means of Network Time Protocol (NTP) and real time clock (RTC); receiver motion is verifiedby the means of dead reckoning and inertial measurement unit (IMU); receiver navigation data is verified by themeans of asymmetric cryptography and Galileo Open Service Navigation Message Authentication (OSNMA).The computational overhead is analyzed as well as cost and worldwide Market feasibility. We estimate thateven basic timing devices would only have to perform one NTP request every 17 days and a microcontrollerpowerful enough to do OSNMA costs less than $2. Finally, the benefits of multi-band receivers and futuredevelopments in both the user and space segments are discussed.

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  • 321.
    Björklund, Thomas
    et al.
    Luleå University of Technology.
    Brodnik, Andrej
    Nordlander, Johan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Formal verification of a trie-based data structure2005Conference paper (Refereed)
  • 322.
    Björkman, Anna
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Nyttan med Internet of Things i Offentliga Verksamheter: Att identifiera nyttor, fördelar och utmaningar2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Internet of Things (IoT) är ett hett ämne i dagens samhälle då inte bara saker utan även människor kan kopplas upp mot nätet. För verksamheter ses stora fördelar med att använda sig av tekniken i syfte att ligga i framkant och bli effektivare i sina arbetsprocesser. Denna studie fördjupar sig i vilka identifierade nyttor, fördelar och utmaningar som finns samt om det verkligen finns behov av Internet of Things i verksamheter.

    Studien utgår ifrån en av Region Skånes förvaltningar, Regionservice, som befinner sig på en omfattande digitaliseringsresa av att implementera en ny systemlösning. De intervjuer som gjorts med anställda inom förvaltningen har varit i huvudsakligt syfte att skapa en förståelse för hur den nya systemlösningen kommer att fungera samt deras tankar om att använda Internet of Things. Tillsammans med studiens teori, som fokuserat på nyttor, fördelar och utmaningar med IoT, avslutas studien med en slutsats som är grundad i teorin och den empiriska undersökningen på Regionservice. I slutsatsen presenteras egna åsikter och tankar om hur IoT kommer att bidra med något behov och nytta inom verksamheterna samt vilken påverkan och utmaningar som kan uppstå.

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  • 323.
    Björnerud, Philip
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Anomaly Detection in Log Files Using Machine Learning2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Logs generated by the applications, devices, and servers contain information that can be used to determine the health of the system. Manual inspection of logs is important, for example during upgrades, to determine whether the upgrade and data migration were successful. However, manual testing is not reliable enough, and manual inspection of logs is tedious and time-­consuming. In this thesis, we propose to use the machine learning techniques K­means and DBSCAN to find anomaly sequences in log files. This research also investigated two different kinds of data representation techniques, feature vector representation, and IDF representation. Evaluation metrics such as F1 score, recall, and precision were used to analyze the performance of the applied machine learning algorithms. The study found that the algorithms have large differences regarding detection of anomalies, in which the algorithms performed better in finding the different kinds of anomalous sequences, rather than finding the total amount of them. The result of the study could help the user to find anomalous sequences, without manually inspecting the log file.

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  • 324.
    Bladh, Thomas
    et al.
    Luleå University of Technology.
    Carr, David A.
    Luleå University of Technology.
    Kljun, Matjaz
    University of Primorska.
    The effect of animated transitions on user navigation in 3D tree-maps2005In: Proceedings: Ninth International Conference on Information Visualisation : 06 - 08 July 2005, London, England / [ed] Ebad Banissi, Los Alamitos, Calif: IEEE Computer Society, 2005, p. 297-305Conference paper (Refereed)
    Abstract [en]

    This paper describes a user study conducted to evaluate the use of smooth animated transitions between directories in a three-dimensional, tree-map visualization. We looked specifically at the task of returning to a previously visited directory after either an animated or instantaneous return to the root location. The results of the study show that animation is a double-edged sword. Even though users take more shortcuts, they also make more severe navigational errors. It seems as though the promise of a more direct route to the target directory, which animation provides, somehow precludes users who navigate incorrectly from applying a successful recovery strategy.

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  • 325.
    Bladh, Thomas
    et al.
    Luleå University of Technology.
    Carr, David A.
    Luleå University of Technology.
    Scholl, Jeremiah
    Luleå University of Technology.
    Extending tree-maps to three dimensions: a comparative study2004In: Computer Human Interaction: 6th Asia Pacific Conference, APCHI 2004, Rotorua, New Zealand, June 29-July 2, 2004. Proceedings / [ed] M. Masoodian; S. Jones; B. Rogers, Springer, 2004, p. 50-59Conference paper (Refereed)
    Abstract [en]

    This paper presents StepTree, an information visualization tool designed for depicting hierarchies, such as directory structures. StepTree is similar to the hierarchy-visualization tool, Treemap, in that it uses a rectangular, space-filling methodology, but differs from Treemap in that it employs three-dimensional space, which is used to more clearly convey the structural relationships of the hierarchy. The paper includes an empirical study comparing typical search and analysis tasks using StepTree and Treemap. The study shows that users perform significantly better on tasks related to interpreting structural relationships when using StepTree. In addition, users achieved the same performance with StepTree and Treemap when doing a range of other common interpretative and navigational tasks.

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  • 326.
    Bladh, Thomas
    et al.
    Luleå University of Technology.
    Carr, David
    Luleå University of Technology.
    Scholl, Jeremiah
    Extending tree-maps to three dimensions: a comparative study2004Report (Other academic)
    Abstract [en]

    This paper presents StepTree, an information visualization tool designed for depicting hierarchies, such as directory structures. StepTree is similar to the hierarchy-visualization tool, Treemap, in that it uses a rectangular, space-filling methodology, but differs from Treemap in that it employs threedimensional space, which is used to more clearly convey the structural relationships of the hierarchy. The paper includes an empirical study comparing typical search and analysis tasks using StepTree and Treemap. The study shows that users perform significantly better on tasks related to interpreting structural relationships when using StepTree. In addition, users achieved the same performance with StepTree and Treemap when doing a range of other common interpretative and navigational tasks.

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  • 327.
    Blaszczyk, Martin
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Autonomous Quadcopter Landing with Visual Platform Localization2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Multicopters such as quadcopters are a popular tool within industries such as mining, shipping and surveillance where a high level of autonomy can save time, increase efficiency and most importantly provide safety. While Unmanned Aerial Vehicles have been a big area in research and used in the mentioned industries, the level of autonomy is still low. Simple actions such as loading and offloading payload or swapping batteries is still a manual task performed by humans. If multicopters are to be used as an autonomous tool the need for solutions where the machines can perform the simplest task such as swapping batteries become an important stepping stone to reach the autonomy goals. Earlier works propose landing solutions focused on landing autonomous vehicles but the lack of accuracy is hindering the vehicles to safely dock with a landing platform. This thesis combines multiple areas such as trajectory generation, visual marker tracking and UAV control where results are shown in both simulation and laboratory experiments. With the use of a Model Predictive Controller for both trajectory generation and UAV control, a multicopter can safely land on a small enough platform which can be mounted on a small mobile robot. Additionally an algorithm to tune the trajectory generator is presented which shows how much weights can be increased in the MPC controller for the system to remain stable. 

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  • 328.
    Blech, Jan Olaf
    et al.
    RMIT University, Melbourne.
    Lindgren, Per
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Pereira, David
    ISEP, Instituto Superior de Engenharia do Porto.
    Vyatkin, Valeriy
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zoitl, Alois
    fortiss GmbH, Munich.
    A Comparison of Formal Verification Approaches for IEC 614992016In: 2016 IEEE 21st International Conference on Emerging Technologies and Factory Automation (ETFA): Berlin, 6-9 Sept. 2016, Piscataway, NJ: IEEE conference proceedings, 2016, article id 7733636Conference paper (Refereed)
    Abstract [en]

    Engineering and computer science have come up with a variety of techniques to increase the confidence in systems, increase reliability, facilitate certification, improve reuse and maintainability, improve interoperability and portability. Among them are various techniques based on formal models to enhance testing, validation and verification. In this paper, we are concentrating on formal verification both at runtime and design time of a system. Formal verification of a system property at design time is the process of mathematically proving that the property indeed holds. At runtime, one can check the validity of the property and report deviations by monitoring the system execution. Formal verification relies on semantic models, descriptions of the system and its properties. We report on ongoing verification work and present two different approaches for formal verification of IEC 61499-based programs. We provide two examples of ongoing work to exemplify the design and the runtime verification approaches

  • 329.
    Blixt, Fanny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Real-time auto-test monitoring system2021Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At Marginalen Bank, there are several microservices containing endpoints that are covered bytest automation. The documentation of which microservices and endpoints that are covered byautomated tests is currently done manually and is proven to contain mistakes. In the documentation, the test coverage for all microservices together and for every individual microserviceis presented. Marginalen Bank needs a way to automate this process with a system that cantake care of test coverage documentation and present the calculated data. Therefore, the purpose of this research is to find a way to create a real-time auto-test monitoring system thatautomatically detects and monitors microservices, endpoints, and test automation to documentand present test automation coverage on a website. The system is required to daily detect andupdate the documentation to be accurate and regularly find eventual changes.

    The implemented system that detects and documents the test automation coverage is calledTest Autobahn. For the system to detect all microservices, a custom hosted service was implemented that registers microservices. All microservices with the custom hosted service installedand extended to registers to Test Autobahn when deployed on a server. For the system todetect all endpoints of each microservice, a custom middleware was implemented that exposesall endpoints of a microservice with it installed. For the microservices to be able to install theseand get registered, a NuGet package containing the custom hosted service and the custom middleware, was created. To detect test automations, custom attributes models were created thatare supposed to be inserted into each test automation project. The custom attributes are placedin every test class and method within a project, to mark which microservice and endpoint thatis being tested within every automated test. The attributes of a project can be read throughthe assembly. To read the custom attributes within every test automation project, a consoleapplication, called Test Autobahn Automation Detector (TAAD), was implemented. TAADreads the assembly to detect the test automations and sends them to Test Autobahn. Test Autobahn couples the found test automation to the corresponding microservices and endpoints.TAAD is installed and ran on the build pipeline in Azure DevOps for each test automationproject to register the test automations.

    To daily detect and update the documentation of the test coverage, Quartz.NET hosted serviceis used. With Quartz.NET implemented, Test Autobahn can execute a specified job on a schedule. Within the job, Test Autobahn detects microservices and endpoints and calculates the testautomation coverage for the detection. The calculation of the test coverage from the latestdetection is presented on the webpage, containing both the test coverage for all microservicestogether and the test coverage for each microservice. According to the evaluations, the systemseems to function as anticipated, and the documentation is displaying the expected data. 

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  • 330.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Quality issues in Internet packet forwarding2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis addresses quality issues in Internet Protocol (IP) packet forwarding. In IP networks, queue mechanisms and scheduling can be used to construct multiple forwarding behaviors. Thereby, both relative and independent services can be offered to Internet users. Independent services offer forwarding qualities known beforehand. Users are assumed to explicitly request admission to an independent service from their network provider. With relative services, users switch between these services to find one that provides an appealing balance between forwarding quality and cost. The thesis makes contributions to three research areas related to forwarding quality in IP networks; differentiating forwarding mechanisms, admission control for differentiated services, and forwarding quality in radio networks carrying Internet traffic. It contributes to the first research area with definitions of three recommendations related to offering loss-rate differentiation (i.e., multiple drop precedence levels). These recommendations are; (1) the total forwarding quality at congested links should not be degraded due to actions taken to create loss-rate differentiation, (2) traffic at high drop precedence levels should always be given a useful share of available forwarding resources, and (3) users should be able to predict the change in loss-rates when switching between drop precedence levels. We specify and evaluate properties of queue mechanisms following these recommendations. Also, as a contribution to the first research area, a new set of forwarding behaviors is specified and analyzed. These forwarding behaviors are suitable for rate-adaptive and delay-sensitive applications with limited loss-tolerance. Applications needing loss-free forwarding of specific packets can be said to have limited loss tolerance. We define and evaluate a scheduling mechanism creating these forwarding behaviors that can be implemented efficiently. The contribution to the second research area is a mechanism for admission control giving assurances on loss-rates to rate varying applications is defined. With this mechanism, dynamic per-link admission thresholds are used to limit committed aggregate rates. To allow for high link utilization through statistical multiplexing we specify a method to adjust these thresholds using low impact traffic monitoring mechanisms commonly available in legacy routers. In radio networks carrying IP traffic, radio transmissions can be scheduled differently to balance spectrum utilization and the forwarding quality provided. Also, parameters settings can be used to optimize the forwarding quality in radio networks for certain transport protocols and applications. This thesis analyses delay spikes experienced by IP traffic in cellular radio networks. We evaluate two different radio-block scheduling mechanisms’ impact on two versions of the Transmission Control Protocol (TCP) (i.e., TCP Sack and TCP Eifel). The evaluation contributes to the third research area by revealing basic dependencies between scheduling, interference, and congestion control mechanisms implemented by TCP. Finally, the thesis contributes to the third research area by proposing extensions to the Internet architecture for inter-layer communication. These extensions allow applications and transport protocols to exchange information with radio link layers. Such information exchange can be used to improve the forwarding quality and to customize data and transport features for current radio conditions.

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  • 331.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Queue mechanisms for differentiation in the Internet2000Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis addresses loss-rate differentiation in the Internet. Loss-rate differentiation can be offered by tagging packets with different levels of drop precedence. Multiple drop precedence levels can be used to provide relative service levels and to assure forwarding capacity in the Internet. Assured services offer forwarding qualities known beforehand. This makes them more predictable than relative services. Users are assumed to explicitly request an assured service from their network provider for traffic up to a specified rate. With relative service levels, users switch between these levels to find one that provides an appealing balance between forwarding quality and cost. The policy for drop precedence probabilities defines the type of loss-rate differentiation pro-vided. Sheltered loss-rate (SLR) differentiation is offered by strictly giving drops to traffic at high drop precedence levels. Sheltering means that traffic at a low drop precedence level is protected from losses caused by traffic at higher levels. Such protection is required for assured services. Relative loss-rate (RLR) differentiation is offered when drop precedence probabilities are rela-tively distributed between drop precedence levels. Offering fixed relations in these probabilities further refines RLR differentiation, resulting in proportional loss-rate (PLR) differentiation. This thesis defines three recommendations associated with providing loss-rate differentiation. Such differentiation can be created with queue mechanisms. We specify and evaluate the proper-ties of differentiating queue mechanisms that make them capable of meeting the recommenda-tions defined. These evaluations are made with simulations. Firstly, the total forwarding quality at congested links should not be degraded due to actions taken to create loss-rate differentiation. The total forwarding quality includes packet loss patterns and delay variations. These quality metrics are high when packet drops are delayed. When pro-viding loss-rate differentiation, drops can be delayed through only dropping packets as they ar-rive. Dropping packets from queues enables immediate drops. This thesis shows that with imme-diate drops less bursty loss patterns and lower delay variations are achieved than with delayed drops. Secondly, traffic at high drop precedence levels should always be given a useful share of avail-able forwarding resources. Such traffic may experience high loss-rates, but should not become starved. Traffic at high levels may become starved due to overloading of traffic at lower levels when creating SLR differentiation. Starvation can be avoided with proper control of low drop precedence traffic. This control may, however, fail due to changes in the network routing topol-ogy, inaccurate admission control, etc. To avoid starvation without relying on proper traffic con-trol, this thesis presents a new queuing mechanism that falls back from offering sheltering to providing RLR differentiation during overloading of low drop precedence traffic. Thirdly, PLR differentiation should be predictable. Users should be able to predict the change in loss-rates when switching between drop precedence levels. PLR differentiation requires relations in loss-rates to be fixed to pre-configured target ratios. Running estimates of loss-rate ratios can be used as feedback to adjust towards these targets if the actual loss-rate ratios deviate from the target ratios. To provide predictable PLR differentiation, these estimates need to be accurate and stable at varying traffic loads. Moreover, they need to detect traffic load variations rapidly. This thesis presents a loss-rate estimator that provides accurate, stable and rapid detection of loss-rate ratios at varying traffic loads.

  • 332.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Dadhich, Siddharth
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Uhlin, Erik
    Volvo CE AB, Bolindervägen 100, 631 85 Eskilstuna, Sweden.
    Marklund, Ulf
    Boliden Mineral AB, Kontorsvägen 1, 936 81 Boliden, Sweden.
    Häggström, Derny
    Oryx Prototyping AB, Tvistevägen 48, 907 36 Umeå, Sweden.
    Remote Controlled Short-Cycle Loading of Bulk Material in Mining Applications2015In: IFAC-PapersOnLine, E-ISSN 2405-8963, Vol. 48, no 17, p. 54-59Article in journal (Refereed)
    Abstract [en]

    High-capacity wireless IP networks with limited delays are nowadays being deployed in both underground and open-pit mines. This allows for advanced remote control of mining machinery with improved feedback to operators and extensive monitoring of machine status, wear and fatigue. Wireless connectivity varies however depending on channel impairments caused by obstacles, multi-path fading and other radio issues. Therefore remote control and monitoring should be capable of adapting their sending rates to handle variations in communications quality. This paper presents key challenges in advanced remote control and monitoring of working machines via high-capacity wireless IP networks in mining environments. We reason about these challenges in context of underground short-cycle load, haul and dump operation with large-volume built wheel-loaders and present a generic communication solution for an operator assistance concept capable of adapting to varying communication properties

  • 333.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Christofferson, André
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Chiquito, Alex
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Rodahl, Johan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Application-scoped Access Control for the Construction Industry2021In: 2021 26th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA), IEEE, 2021, p. 1-8Conference paper (Refereed)
    Abstract [en]

    The construction industry is characterized by its extensive and dynamic collaborations between contractors providing various services and expertise. In such eco-systems, the secure sharing of information, data and equipment challenges the access control needs to be application agnostic. Furthermore, it needs fine-grained access policies including means for abstraction to ease administration, and support for delegated authorization in Service-Oriented Architecture (SOA) based systems. In this paper, we explore the use of delegated access using OAuth 2.0 with Attribute-Based Access Control (ABAC) for the collaborative sharing of equipment at construction sites. In particular, we investigate the use of contextual attributes to capture the dynamic aspects, such as location and urgency, in the booking of construction lifts. Through this study, we propose a solution based on the IoT Application-scoped Access Control as a Service (IAACaaS) architecture model combined with NIST Next Generation Access Control (NGAC). We present an architecture for a general Identity and Access Management (IAM) system for the construction industry, and provide a design and guide for implementation of this architecture in terms how key functionalities should be captured as reusable micro-services. Moreover, we describe how these micro-services can be combined to make the system a general and reusable solution providing access control for collaborative sharing of data, information and equipment at construction sites.

  • 334.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Dhanrajani, Siddhant
    Karlsruhe Institute of Technology (KIT), wbk Institute of Production Science, Kaiserstr. 12, 76131 Karlsruhe, Germany.
    Abdalla, Abdelrahman H.
    Politecnico di Milano, Department of Mechanical Engineering, Via la Masa 1, 20156, Milan, Italy.
    Diani, Marco
    Politecnico di Milano, Department of Mechanical Engineering, Via la Masa 1, 20156, Milan, Italy.
    Klenk, Felix
    Karlsruhe Institute of Technology (KIT), wbk Institute of Production Science, Kaiserstr. 12, 76131 Karlsruhe, Germany.
    Colledani, Marcello
    Politecnico di Milano, Department of Mechanical Engineering, Via la Masa 1, 20156, Milan, Italy.
    Palm, Emanuel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Demand-supply matching through auctioning for the circular economy2021In: 10th CIRP Sponsored Conference on Digital Enterprise Technologies (DET 2020) – Digital Technologies as Enablers of Industrial Competitiveness and Sustainability / [ed] Jozsef Vancza; Paul Maropoulos, Elsevier, 2021, p. 82-87Conference paper (Refereed)
    Abstract [en]

    The circular economy aims to reduce the consumption of resources and energy by exploiting multiple use-cycles of components and materials. The creation of new circular businesses hinges on efficient alignment between market demands of circular products with the supply of End-of-life components and materials. In this paper, we address the digitization of a matchmaking tool for the circular economy by defining demand-supply matching (DSM) in context of business link identification and cross-sectorial matchmaking. We further specify a DSM process and p resent our DSM tool, which facilitates publication and search for supplier offerings and demander needs, selection of auctioning candidates, and digitized auctioning and contract definition. By that, this tool supports the alignment of market demands with matching supply offerings. In particular, it combines the steps of publishing, searching, selecting, auctioning and contract definition into one tool, which we argue can make matchmaking more efficient compared to addressing these steps separately. Finally, we present the design of the tool and discuss its merits in light of the needed acceptance for automating business link identification and contractual interactions.

  • 335.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Jonsson, Andreas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    On creating proportional loss-rate differentiation: predictability and performance2001In: Quality of Service - IWQoS 2001: 9th International Workshop Karlsruhe, Germany, June 6-8, 2001 Proceedings / [ed] Lars Wolf, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2001, p. 372-386Conference paper (Refereed)
    Abstract [en]

    Recent extensions to the Internet architecture allow assignment of different levels of drop precedence to IP packets. This paper examines differentiation predictability and implementation complexity in creation of proportional lossrate (PLR) differentiation between drop precedence levels. PLR differentiation means that fixed loss-rate ratios between different traffic aggregates are provided independent of traffic loads. To provide such differentiation, running estimates of loss-rates can be used as feedback to keep loss-rate ratios fixed at varying traffic loads. In this paper, we define a loss-rate estimator based on average drop distances (ADDs). The ADD estimator is compared with an estimator that uses a loss history table (LHT) to calculate loss-rates. We show, through simulations, that the ADD estimator gives more predictable PLR differentiation than the LHT estimator. In addition, we show that a PLR dropper using the ADD estimator can be implemented efficiently.

  • 336.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Drop strategies and loss-rate differentiation2001In: Proceedings: Ninth International Conference on Network Protocols, ICNP 2001 : 11 - 14 November 2001, Riverside, California, USA, Los Alamitos, Calif: IEEE Communications Society, 2001, p. 146-154Conference paper (Refereed)
    Abstract [en]

    When offering loss-rate differentiation in IP networks, the drop strategy used can have a considerable influence on packet loss and delay. In particular, a strategy of dropping packets only as they arrive can cause bursty loss patterns and high jitter. When only arriving packets are dropped, the router may need to wait for low priority packets to arrive before dropping any packet. This results in larger queue oscillation than if low priority packets were dropped immediately from the queue. Queue oscillation gives bursty loss patterns and delay jitter. We present simulations showing that dropping packets from the queue gives smoother loss patterns and less jitter than if packets are dropped only as they arrive. These simulations cover both TCP Sack and TCP Reno. WRED with and without the gentle modification is used to make drop decisions.

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  • 337.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology. Telia research AB, Luleå, Sweden.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology. Swedish Institute of Computer Science (SICS), Kista, Sweden.
    Pink, Stephen
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Load-tolerant differentiation with active queue management2000In: Computer communication review, ISSN 0146-4833, E-ISSN 1943-5819, Vol. 30, no 3, p. 4-16Article in journal (Refereed)
    Abstract [en]

    Current work in the IETF aims at providing service differentiation on the Internet. One proposal is to provide loss differentiation by assigning levels of drop procedence to IP packets. In this paper, we evaluate the active queue management (AQM) mechanisms RED In and Out (RIO) and Weighted RED (WRED) in providing levels of drop precedence under different loads. For low drop precedence traffic, FIO and WRED can be configured to offer sheltering (i.e., low drop precedence traffic is protected from losses caused by higher drop precedence traffic). However, if traffic control fails or is inaccurate, such configurations can cause starvation of traffic at high drop precedence levels. Configuring WRED to instead offer relative differentiation can eliminate the risk of starvation. However, WRED cannot, without reconfiguration, both offer sheltering when low drop precedence traffic is properly controlled and avoid starvation at overload of low drop precedence traffic. To achieve this, we propose a new AQM mechanism, WRED with Thresholds (WRT). The benefit of WRT is that, without reconfiguration, it offers sheltering when low drop precedence traffic is properly controlled and relative differentiation otherwise. We present simulations showing that WRT has these properties.

  • 338.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Vemmervik, Claes
    Operax AB.
    End-to-End QoS control architectures from a wholesale and retail perspective: benefits and challenges2006Conference paper (Refereed)
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  • 339.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Simonsson, Arne
    Ericsson Research, SE – 971 87, Luleå, Sweden.
    Effects on TCP from radio-block scheduling in WCDMA high speed downlink shared channels2003In: Quality for all: 4th COST 263 International Workshop on Quality of Future Internet Services, QoFIS 2003, Stockholm, Sweden, October 1-2, 2003 : proceedings / [ed] Gunnar Karlsson; Michael I. Smirnov, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2003, p. 214-223Conference paper (Refereed)
    Abstract [en]

    Avoiding delay jitter is essential to achieve high throughput for TCP. In particular, delay spikes can cause spurious timeouts. Such timeouts force TCP into slow-start, which may reduce congestion window sizes drastically. Consequently, there may not always be data available for transmission on bottleneck links. For HS-DSCH, jitter can occur due to varying interference. Also, properties of the radio-block scheduling influence the jitter. We evaluate, through simulations, effects on TCP from scheduling. Our evaluation shows that round-robin (RR) schedulers can give more jitter than SIR schedulers. SIR schedulers discriminates low SIR users to improve spectrum utilization while RR schedulers distribute transmission capacity fairly. The high jitter with RR scheduling cause however both lower utilization and decreased fairness in throughput among users than with SIR scheduling. The Eifel algorithm makes TCP more robust against delay spikes and reduces thereby these problems

  • 340.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Wolosz, Krzysztof
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Proportional throughput differentiationwith cognitive load-control on WSN channels2015In: EURASIP Journal on Wireless Communications and Networking, ISSN 1687-1472, E-ISSN 1687-1499, no 1, article id 186Article in journal (Refereed)
    Abstract [en]

    Wireless sensor networks are nowadays used in various applications to facilitate monitoring and actuation tasks, e.g., for smart grids and industrial automation. Some of these applications require guarantees or at least assurances on reliability. Such applications expect predictable throughput and delay, which are hard to maintain in environments with changing radio conditions. QoS-aware MAC protocols capable of handling such environments are well explored. They require however protocol changes and are therefore difficult to deploy. This paper presents an application layer forwarding service that offers proportional differentiation while limiting network load to preserve high utilization and predictability. Demands for capacity are expressed as fractions of the overall channel throughput. We show that this service can be implemented with a cognitive load controller (CLC) based on fuzzy logic and quality assessed with utility functions for application layer packet loss and throughput. We evaluate the CLC for 802.15.4 with CSMA/CA through NS-3 simulations showing that it offers the intended service while adjusting load for high overall throughput and low delay

  • 341.
    Bohli, Jens-Mathias
    et al.
    NEC Laboratories Europe.
    Kurpatov, Roman
    NEC Laboratories Europe.
    Schmidt, Mischa
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Selective Decryption of Outsourced IoT Data2015In: 2015 IEEE 2nd World Forum on Internet of Things (WF-IoT): Milan, Italy, 14-16 Dec, 2015, Piscataway, NJ: IEEE Communications Society, 2015, p. 739-744Conference paper (Refereed)
    Abstract [en]

    Outsourcing of IoT-data is a common concept when using third-party services, e.g. an external building management service is given access to the building's sensor measurements. However, the measurements captured from building systems often need to be protected from unauthorized access, because they are linked to persons, processes or business secrets, and therefore data protection requirements apply. Nevertheless, due to the large data volumes, external storage is desirable from a business perspective. We propose the concept of a Security Broker based on symmetric encryption schemes. It offers a key management scheme to flexibly create short decryption keys for time intervals or specific ranges of measurement values. We further show how the scheme can be generalized or a combination of the schemes can be applied. We implemented a prototype in Java and analyzed its performance. The evaluation proved the mechanism's applicability for mainstream applications running on off-the-shelf computing equipment.

  • 342.
    Bojrup, Elsa
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Moestam, Linn
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Utmaningar med RPA-implementation i offentlig verksamhet2020Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Denna studie ämnar identifiera utmaningar och aspekter som en offentlig verksamhet behöverta hänsyn till vid en RPA-implementation. Studien har utförts i en offentlig verksamhet som äri behov av att automatisera genom att implementera RPA. Förarbetet till denna RPAimplementation som skett iterativt har i denna studie observerats under workshops, observationoch intervju. Utförandet av studien har skett genom att genomföra en fallstudie i en offentligverksamhet med ett explorativt angreppssätt, kvalitativ datainsamling och en abduktiv ansats.Resultatet från datainsamlingstillfällena analyserades genom tematisk analys med två olikaperspektiv; teoridrivet och datadrivet. Utifrån det teoridrivna perspektivet analyserades empirinmot de teman som utvanns ifrån de teoretiska koncept som sammanfattats från tidigare studierom RPA och RPA-implementation. Efter att ställt teorin mot empirin blev resultatet att falletskaraktär var i linje med nio av de femton teoretiska koncepten. De koncept som inte påträffadesi detta fall samlades under temat ”Det är viktigt att välja rätt process för en RPAimplementation”. Det datadrivna perspektivet identifierade nya aspekter som offentligaverksamheter behöver beakta vid implementation av RPA. Den första slutsatsen är att detviktigt att välja rätt process inför en RPA-implementation. Den andra slutsatsen är aspektenom att offentliga verksamheter måste hantera mycket känsliga uppgifter och att det är enutmaning vid implementation av RPA.

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  • 343.
    Bomark, Peter
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Evertsen, Gunn
    Northern Research Institute.
    Brox, Ellen
    Northern Research Institute.
    Hirche, Johannes
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Yliräisänen-Seppänen, Pia
    Rovaniemi University of Applied Sciences.
    A prototype social learning platform for children with diabetes type 12012In: Proceeding of the 16th International Academic MindTrek Conference 2012: Envision Future Media Environments, New York: Association for Computing Machinery, Inc. , 2012, p. 211-213Conference paper (Refereed)
    Abstract [en]

    Children diagnosed with diabetes type 1 are bombarded with information and have a hard time understanding it all. Existing information material consists mostly ofbrochures and textbooks, giving little opportunity for testing and trial-and-error without consequences. A social platform with learning games gives the children an opportunity to experiment and find peer support, which is important for coping with a life long disease.

  • 344.
    Bomark, Peter
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Hirche, Johannes
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Hagman, Olle
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Colour visualisation of real virtual timber using image quilting2015In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 73, no 6, p. 837-839Article in journal (Refereed)
    Abstract [en]

    When presenting images of wood obtained through x-ray computed tomography to an audience inexperienced in interpreting radiological images, explaining the correspondence between mass attenuation and features of wood could be time consuming and confusing. Realistically colourised attenuation images might be a suitable option in order to facilitate understanding of the images. Mass attenuation and colour of wood does not have a simple correlation, so naive grey-scale to colour conversion does not work. This paper describes how image quilting can be used to transfer colour information from a image pair where both mass attenuation and colour is known to a target mass attenuation image. An example of this method applied on scots pine shows that it is capable of retaining the major structures of wood, such as year rings and knots. The method could allow for easier understanding of simulation studies where logs scanned using x-ray computed tomography are virtually sawn.

  • 345.
    Bomström, Henri
    et al.
    M3S Research Unit, University of Oulu, Pentti Kaiteran Katu 1, 90014 Oulu, Finland.
    Annanperä, Elina
    M3S Research Unit, University of Oulu, Pentti Kaiteran Katu 1, 90014 Oulu, Finland.
    Kelanti, Markus
    M3S Research Unit, University of Oulu, Pentti Kaiteran Katu 1, 90014 Oulu, Finland.
    Xu, Yueqiang
    M3S Research Unit, University of Oulu, Pentti Kaiteran Katu 1, 90014 Oulu, Finland.
    Mäkelä, Satu-Marja
    VTT Technical Research Centre of Finland Ltd, Kaitoväylä 1, 90571 Oulu, Finland.
    Immonen, Milla
    VTT Technical Research Centre of Finland Ltd, Kaitoväylä 1, 90571 Oulu, Finland.
    Siirtola, Pekka
    BISG Research Group, University of Oulu, Pentti Kaiteran Katu 1, 90014 Oulu, Finland.
    Teern, Anna
    M3S Research Unit, University of Oulu, Pentti Kaiteran Katu 1, 90014 Oulu, Finland.
    Liukkunen, Kari
    M3S Research Unit, University of Oulu, Pentti Kaiteran Katu 1, 90014 Oulu, Finland.
    Päivärinta, Tero
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Digital Services and Systems. M3S Research Unit, University of Oulu, Pentti Kaiteran Katu 1, 90014 Oulu, Finland;;Luleå University of Technology, Digital Services and Systems, Porsön, 971 87, Luleå, Sweden.
    Digital Twins About Humans—Design Objectives From Three Projects2022In: Journal of Computing and Information Science in Engineering, ISSN 1530-9827, E-ISSN 1944-7078, Vol. 22, no 5, article id 050907Article in journal (Refereed)
    Abstract [en]

    Digital twin (DT) emerges as a key concept of the Industry 4.0 paradigm and beyond. However, the current literature lacks focus on humans and human activities as a part of complex system DTs. Acknowledging human aspects in DTs can enhance work performance, well-being, motivation, and personal development of professionals. This study examines emerging requirements for human digital twins (HDTs) in three use cases of industry–academia collaboration on complex systems. The results draw together the overall design problem and four design objectives for HDTs. We propose to combine the machine and human-related aspects of DTs and highlight the need for virtual-to-virtual interoperability between HDTs and machines alike. Furthermore, we outline differences between humans and machines regarding digital twinning by addressing human activities and knowledge-based behavior on systems. Design of HDTs requires understanding of individual professional characteristics, such as skills and information preferences, together with twinning between the physical and digital machine entities and interactions between the human and machine DTs. As the field moves toward including humans as a part of the DT concept, incorporating HDTs in complex systems emerges as an increasingly significant issue.

  • 346.
    Booth, Frederick
    et al.
    Department of Accounting, Finance & Economics, Belfast, United Kingdom.
    Potts, Courtney
    School of Psychology, Ulster University, Coleraine, United Kingdom.
    Bond, Raymond
    School of Computing, Ulster University, Belfast, United Kingdom.
    Mulvenna, Maurice
    School of Computing, Ulster University, Belfast, United Kingdom.
    Kostenius, Catrine
    Luleå University of Technology, Department of Health, Learning and Technology, Nursing and Medical Technology.
    Dhanapala, Indika
    Nimbus Research Centre, Munster Technological University, Cork, Ireland.
    Vakaloudis, Alex
    Nimbus Research Centre, Munster Technological University, Cork, Ireland.
    Cahill, Brian
    Nimbus Research Centre, Munster Technological University, Cork, Ireland.
    Kuosmanen, Lauri
    Department of Nursing Science, University of Eastern Finland, Kuopio, Finland.
    Ennis, Edel
    School of Psychology, Ulster University, Coleraine, United Kingdom.
    A Mental Health and Well-Being Chatbot: User Event Log Analysis2023In: JMIR mhealth and uhealth, E-ISSN 2291-5222, Vol. 11, article id e43052Article in journal (Refereed)
    Abstract [en]

    Background: Conversational user interfaces, or chatbots, are becoming more popular in the realm of digital health and well-being. While many studies focus on measuring the cause or effect of a digital intervention on people’s health and well-being (outcomes), there is a need to understand how users really engage and use a digital intervention in the real world.

    Objective: In this study, we examine the user logs of a mental well-being chatbot called ChatPal, which is based on the concept of positive psychology. The aim of this research is to analyze the log data from the chatbot to provide insight into usage patterns, the different types of users using clustering, and associations between the usage of the app’s features.

    Methods: Log data from ChatPal was analyzed to explore usage. A number of user characteristics including user tenure, unique days, mood logs recorded, conversations accessed, and total number of interactions were used with k-means clustering to identify user archetypes. Association rule mining was used to explore links between conversations.

    Results: ChatPal log data revealed 579 individuals older than 18 years used the app with most users being female (n=387, 67%). User interactions peaked around breakfast, lunchtime, and early evening. Clustering revealed 3 groups including “abandoning users” (n=473), “sporadic users” (n=93), and “frequent transient users” (n=13). Each cluster had distinct usage characteristics, and the features were significantly different (P<.001) across each group. While all conversations within the chatbot were accessed at least once by users, the “treat yourself like a friend” conversation was the most popular, which was accessed by 29% (n=168) of users. However, only 11.7% (n=68) of users repeated this exercise more than once. Analysis of transitions between conversations revealed strong links between “treat yourself like a friend,” “soothing touch,” and “thoughts diary” among others. Association rule mining confirmed these 3 conversations as having the strongest linkages and suggested other associations between the co-use of chatbot features.

    Conclusions: This study has provided insight into the types of people using the ChatPal chatbot, patterns of use, and associations between the usage of the app’s features, which can be used to further develop the app by considering the features most accessed by users.

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  • 347.
    Booth, Todd
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Digital Services and Systems.
    Design Principles for Network Distributed Denial of Service Defense2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    People, organizations and society are become more and more dependent upon access to Information Systems. Most Information Systems are accessible via the Internet. It is becoming easier and easier to perform successful network attacks against these Information Systems, which causes the system to become unavailable for its intended users. It is also very inexpensive to launch a successful network DRDoS attack against an organization’s servers. One type of distributed denial of service (DDoS) network attack sends a very large volume of traffic towards the victim’s servers. The most common of these volumetric DDoS attacks are described as reflective DDoS service (DRDoS) attacks and the DRDoS defense is the main contribution of this thesis. For years, you have been able to even rent network attack services from criminal organizations, which are often in the form of DRDoS network attacks.

    The Design Science Research (DSR) approach was used for my research. Included are the DSR cycles performed, including the artifact evaluations. The relationship between the DSR cycles and the published research papers is presented in the paper summary section. The first two papers formed the DSR problem definition. The next three papers used a variety of information hiding techniques to mitigate network attacks. The last paper proposed a different design principle, based on filtering traffic before it reached the public cloud providers. This proposed DRDoS defense approach is to have the public cloud provider request their IP neighbors to filter or drop certain traffic for a big IP block of IP addresses. Then the provider gives IP addresses to their customers, who want this protection, from the big IP block. This way the provider can provide DRDoS protection for hundreds of thousands of customers, with a few firewall rules and the filtering of malicious traffic occurs at the network edge. This solution prevents most of the DRDoS attack traffic from even reaching the public cloud provider. This last research is focused on protecting servers from DRDoS attacks, where the servers are accessible via the Internet and where the servers are or can be hosted via a public cloud provider. This public cloud provider hosting includes accessibility via cloud offerings, such as with Amazon’s Web Services (AWS), Google’s Compute Cloud (GCP), and Microsoft’s Azure. To simplify the discussion, this thesis will focus on Web servers, as the example.

    The research has been generalized into the following two research design principal contributions. My thesis, including the design principles, contributes to the state of the art network DDoS defense in the following ways:

    1. Divide and Search for Malicious Network Traffic. After the attack is detected, the IP, Web, and/or DNS address information is changed  This mitigates the attacks since the attacker will not be able to quickly learn the new DNS, Web, or IP connectivity information. This has the effect to reduce or mitigate the effect of the DDoS attacks.

    2.  Ask IPX Neighbors to Pre-process Network Traffic. With this design principle, we have two types of features. One feature is to stop malicious traffic. This mitigates the attacks at the public cloud provider’s neighbors, so that most of the malicious traffic never even arrives to the cloud provider. This way, the cloud provider no longer needs to process the malicious traffic to filter it out. The other feature is to provide a different quality of service (QoS) for incoming traffic. This allows the public cloud provider’s neighbor to treat the traffic as higher or lower priority traffic.

    In this thesis, the contributions are how to improve the state of the art DDoS defense solutions, concerning network attacks against Internet accessible servers. We believe that our DRDoS defense contribution is better, more efficient, and/or more effective than the current state of the art DDRoS solutions. Our contributions are focused on network layer attacks as opposed to application, presentation, or transport layer attacks.

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  • 348.
    Booth, Todd
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Critical Infrastructure Network DDoS Defense, via Cognitive Learning2017In: / [ed] Pietro Manzoni, Universitat Politècnica de València, Spain, Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2017Conference paper (Refereed)
    Abstract [en]

    Some public and private services are called part of the Critical Infrastructure (CI), which are considered as the most important services to protect the functioning of a society and the economy.  Many CIs provide services via the Internet and thus cyber-attacks can be performed remotely.  It is now very simple and free to find and download software, which automates performing cyber-attacks.  A recent example is that two teenagers, with close to no security knowledge, created an on-line business. They would run cyber-attacks (online booter service called vDOS, as reported by Brian Krebs) for a small fee. They reportedly earned over 600,000 USD in a short period of time by conducting a large number of automated DDoS cyber-attacks. Then Krebs was retaliated against, and the highest DDoS attack bandwidth ever recorded, 620 Gbps, was launched against Krebs. In this paper we show how cognitive learning can be used to significantly mitigate any effects of DDoS network attacks, against the critical infrastructure.

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  • 349.
    Booth, Todd
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    DNS DDoS Mitigation, via DNS Timer Design Changes2017In: Future Network Systems and Security: Third International Conference, FNSS 2017, Gainesville, FL, USA, August 31 - September 2, 2017, Proceedings / [ed] Robin Doss, Welwyn Piramuthu, Wei Zhou, Springer, 2017, p. 43-55Conference paper (Refereed)
    Abstract [en]

    DDoS attacks have been a problem since 2000. In October 2016, there was a major DDoS attack against the service provider Dyn’s DNS service, which took the service down. This was one of the largest bandwidth DDoS attack ever documented, with attack bandwidth over 650 Gbps. By taking down just Dyn’s DNS service, clients could not obtain the IP addresses, of the organizations hosting their DNS with Dyn, such as Twitter. Our contribution is that we have found a way to mitigate the effect of DDoS attacks against DNS services. We only require some very small algorithm changes, in the DNS protocol. More specifically, we propose to add two additional timers. Even if the end DNS clients don’t support these timers, they will receive our new functionality via the DNS resolvers and recursive servers. In summary, our contributions give much more control to the organizations, as to under which specific conditions the DNS cache entries should be aged or used. This allows the organization to (1) much more quickly expire client DNS caches and (2) to mitigate the DDoS DNS attack effects. Our contributions are also helpful to organizations, even if there are no DDoS DNS attack.

  • 350.
    Booth, Todd
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Elimination of DoS UDP Reflection Amplification Bandwidth Attacks, Protecting TCP Services2015In: Future Network Systems and Security: First International Conference, FNSS 2015, Paris, France, June 11-13, 2015, Proceedings / [ed] Robin Doss; Selwyn Piramuthu; Wei Zhou, Encyclopedia of Global Archaeology/Springer Verlag, 2015, p. 1-15Conference paper (Refereed)
    Abstract [en]

    In this paper, we propose a solution to eliminate a popular type of Denial of Service (DoS) attack, which is a DoS amplification attack. Note that a DoS is a subset of of DDoS. Our solution protects servers running any number of TCP services. This paper is focused on the most popular type of DoS amplification attack, which uses the UDP protocol. Via DoS UDP amplification attacks, an attacker can send a 1 Gbps traffic stream to reflectors. The reflectors will then send up 556 times that amount (amplified traffic) to the victim’s server. So just ten PCs, each sending 10Mbps, can send 55 Gbps indirectly, via reflectors, to a victim’s server. Very few ISP customers have 55 Gpbs provisioned. Expensive and complex solutions exist. However our elimination techniques can be implemented very quickly, easily and at an extremely low cost.

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